Sample records for accurate precise specific

  1. Accurate and precise determination of isotopic ratios by MC-ICP-MS: a review.

    PubMed

    Yang, Lu

    2009-01-01

    For many decades the accurate and precise determination of isotope ratios has remained a very strong interest to many researchers due to its important applications in earth, environmental, biological, archeological, and medical sciences. Traditionally, thermal ionization mass spectrometry (TIMS) has been the technique of choice for achieving the highest accuracy and precision. However, recent developments in multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) have brought a new dimension to this field. In addition to its simple and robust sample introduction, high sample throughput, and high mass resolution, the flat-topped peaks generated by this technique provide for accurate and precise determination of isotope ratios with precision reaching 0.001%, comparable to that achieved with TIMS. These features, in combination with the ability of the ICP source to ionize nearly all elements in the periodic table, have resulted in an increased use of MC-ICP-MS for such measurements in various sample matrices. To determine accurate and precise isotope ratios with MC-ICP-MS, utmost care must be exercised during sample preparation, optimization of the instrument, and mass bias corrections. Unfortunately, there are inconsistencies and errors evident in many MC-ICP-MS publications, including errors in mass bias correction models. This review examines "state-of-the-art" methodologies presented in the literature for achievement of precise and accurate determinations of isotope ratios by MC-ICP-MS. Some general rules for such accurate and precise measurements are suggested, and calculations of combined uncertainty of the data using a few common mass bias correction models are outlined.

  2. Hydrogen atoms can be located accurately and precisely by x-ray crystallography.

    PubMed

    Woińska, Magdalena; Grabowsky, Simon; Dominiak, Paulina M; Woźniak, Krzysztof; Jayatilaka, Dylan

    2016-05-01

    Precise and accurate structural information on hydrogen atoms is crucial to the study of energies of interactions important for crystal engineering, materials science, medicine, and pharmacy, and to the estimation of physical and chemical properties in solids. However, hydrogen atoms only scatter x-radiation weakly, so x-rays have not been used routinely to locate them accurately. Textbooks and teaching classes still emphasize that hydrogen atoms cannot be located with x-rays close to heavy elements; instead, neutron diffraction is needed. We show that, contrary to widespread expectation, hydrogen atoms can be located very accurately using x-ray diffraction, yielding bond lengths involving hydrogen atoms (A-H) that are in agreement with results from neutron diffraction mostly within a single standard deviation. The precision of the determination is also comparable between x-ray and neutron diffraction results. This has been achieved at resolutions as low as 0.8 Å using Hirshfeld atom refinement (HAR). We have applied HAR to 81 crystal structures of organic molecules and compared the A-H bond lengths with those from neutron measurements for A-H bonds sorted into bonds of the same class. We further show in a selection of inorganic compounds that hydrogen atoms can be located in bridging positions and close to heavy transition metals accurately and precisely. We anticipate that, in the future, conventional x-radiation sources at in-house diffractometers can be used routinely for locating hydrogen atoms in small molecules accurately instead of large-scale facilities such as spallation sources or nuclear reactors.

  3. Hydrogen atoms can be located accurately and precisely by x-ray crystallography

    PubMed Central

    Woińska, Magdalena; Grabowsky, Simon; Dominiak, Paulina M.; Woźniak, Krzysztof; Jayatilaka, Dylan

    2016-01-01

    Precise and accurate structural information on hydrogen atoms is crucial to the study of energies of interactions important for crystal engineering, materials science, medicine, and pharmacy, and to the estimation of physical and chemical properties in solids. However, hydrogen atoms only scatter x-radiation weakly, so x-rays have not been used routinely to locate them accurately. Textbooks and teaching classes still emphasize that hydrogen atoms cannot be located with x-rays close to heavy elements; instead, neutron diffraction is needed. We show that, contrary to widespread expectation, hydrogen atoms can be located very accurately using x-ray diffraction, yielding bond lengths involving hydrogen atoms (A–H) that are in agreement with results from neutron diffraction mostly within a single standard deviation. The precision of the determination is also comparable between x-ray and neutron diffraction results. This has been achieved at resolutions as low as 0.8 Å using Hirshfeld atom refinement (HAR). We have applied HAR to 81 crystal structures of organic molecules and compared the A–H bond lengths with those from neutron measurements for A–H bonds sorted into bonds of the same class. We further show in a selection of inorganic compounds that hydrogen atoms can be located in bridging positions and close to heavy transition metals accurately and precisely. We anticipate that, in the future, conventional x-radiation sources at in-house diffractometers can be used routinely for locating hydrogen atoms in small molecules accurately instead of large-scale facilities such as spallation sources or nuclear reactors. PMID:27386545

  4. A precise and accurate acupoint location obtained on the face using consistency matrix pointwise fusion method.

    PubMed

    Yanq, Xuming; Ye, Yijun; Xia, Yong; Wei, Xuanzhong; Wang, Zheyu; Ni, Hongmei; Zhu, Ying; Xu, Lingyu

    2015-02-01

    To develop a more precise and accurate method, and identified a procedure to measure whether an acupoint had been correctly located. On the face, we used an acupoint location from different acupuncture experts and obtained the most precise and accurate values of acupoint location based on the consistency information fusion algorithm, through a virtual simulation of the facial orientation coordinate system. Because of inconsistencies in each acupuncture expert's original data, the system error the general weight calculation. First, we corrected each expert of acupoint location system error itself, to obtain a rational quantification for each expert of acupuncture and moxibustion acupoint location consistent support degree, to obtain pointwise variable precision fusion results, to put every expert's acupuncture acupoint location fusion error enhanced to pointwise variable precision. Then, we more effectively used the measured characteristics of different acupuncture expert's acupoint location, to improve the measurement information utilization efficiency and acupuncture acupoint location precision and accuracy. Based on using the consistency matrix pointwise fusion method on the acupuncture experts' acupoint location values, each expert's acupoint location information could be calculated, and the most precise and accurate values of each expert's acupoint location could be obtained.

  5. Precise and accurate isotope ratio measurements by ICP-MS.

    PubMed

    Becker, J S; Dietze, H J

    2000-09-01

    The precise and accurate determination of isotope ratios by inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS (LA-ICP-MS) is important for quite different application fields (e.g. for isotope ratio measurements of stable isotopes in nature, especially for the investigation of isotope variation in nature or age dating, for determining isotope ratios of radiogenic elements in the nuclear industry, quality assurance of fuel material, for reprocessing plants, nuclear material accounting and radioactive waste control, for tracer experiments using stable isotopes or long-lived radionuclides in biological or medical studies). Thermal ionization mass spectrometry (TIMS), which used to be the dominant analytical technique for precise isotope ratio measurements, is being increasingly replaced for isotope ratio measurements by ICP-MS due to its excellent sensitivity, precision and good accuracy. Instrumental progress in ICP-MS was achieved by the introduction of the collision cell interface in order to dissociate many disturbing argon-based molecular ions, thermalize the ions and neutralize the disturbing argon ions of plasma gas (Ar+). The application of the collision cell in ICP-QMS results in a higher ion transmission, improved sensitivity and better precision of isotope ratio measurements compared to quadrupole ICP-MS without the collision cell [e.g., for 235U/238U approximately 1 (10 microg x L(-1) uranium) 0.07% relative standard deviation (RSD) vs. 0.2% RSD in short-term measurements (n = 5)]. A significant instrumental improvement for ICP-MS is the multicollector device (MC-ICP-MS) in order to obtain a better precision of isotope ratio measurements (with a precision of up to 0.002%, RSD). CE- and HPLC-ICP-MS are used for the separation of isobaric interferences of long-lived radionuclides and stable isotopes by determination of spallation nuclide abundances in an irradiated tantalum target.

  6. Mass spectrometry in Earth sciences: the precise and accurate measurement of time.

    PubMed

    Schaltegger, Urs; Wotzlaw, Jörn-Frederik; Ovtcharova, Maria; Chiaradia, Massimo; Spikings, Richard

    2014-01-01

    Precise determinations of the isotopic compositions of a variety of elements is a widely applied tool in Earth sciences. Isotope ratios are used to quantify rates of geological processes that occurred during the previous 4.5 billion years, and also at the present time. An outstanding application is geochronology, which utilizes the production of radiogenic daughter isotopes by the radioactive decay of parent isotopes. Geochronological tools, involving isotopic analysis of selected elements from smallest volumes of minerals by thermal ionization mass spectrometry, provide precise and accurate measurements of time throughout the geological history of our planet over nine orders of magnitude, from the accretion of the proto-planetary disk, to the timing of the last glaciation. This article summarizes the recent efforts of the Isotope Geochemistry, Geochronology and Thermochronology research group at the University of Geneva to advance the U-Pb geochronological tool to achieve unprecedented precision and accuracy, and presents two examples of its application to two significant open questions in Earth sciences: what are the triggers and timescales of volcanic supereruptions, and what were the causes of mass extinctions in the geological past, driven by global climatic and environmental deterioration?

  7. The Rényi divergence enables accurate and precise cluster analysis for localisation microscopy.

    PubMed

    Staszowska, Adela D; Fox-Roberts, Patrick; Hirvonen, Liisa M; Peddie, Christopher J; Collinson, Lucy M; Jones, Gareth E; Cox, Susan

    2018-06-01

    Clustering analysis is a key technique for quantitatively characterising structures in localisation microscopy images. To build up accurate information about biological structures, it is critical that the quantification is both accurate (close to the ground truth) and precise (has small scatter and is reproducible). Here we describe how the Rényi divergence can be used for cluster radius measurements in localisation microscopy data. We demonstrate that the Rényi divergence can operate with high levels of background and provides results which are more accurate than Ripley's functions, Voronoi tesselation or DBSCAN. Data supporting this research will be made accessible via a web link. Software codes developed for this work can be accessed via http://coxphysics.com/Renyi_divergence_software.zip. Implemented in C ++. Correspondence and requests for materials can be also addressed to the corresponding author. adela.staszowska@gmail.com or susan.cox@kcl.ac.uk. Supplementary data are available at Bioinformatics online.

  8. Precise and accurate assay of pregnenolone and five other neurosteroids in monkey brain tissue by LC-MS/MS.

    PubMed

    Dury, Alain Y; Ke, Yuyong; Labrie, Fernand

    2016-09-01

    A series of steroids present in the brain have been named "neurosteroids" following the possibility of their role in the central nervous system impairments such as anxiety disorders, depression, premenstrual dysphoric disorder (PMDD), addiction, or even neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Study of their potential role requires a sensitive and accurate assay of their concentration in the monkey brain, the closest model to the human. We have thus developed a robust, precise and accurate liquid chromatography-tandem mass spectrometry method for the assay of pregnenolone, pregnanolone, epipregnanolone, allopregnanolone, epiallopregnanolone, and androsterone in the cynomolgus monkey brain. The extraction method includes a thorough sample cleanup using protein precipitation and phospholipid removal, followed by hexane liquid-liquid extraction and a Girard T ketone-specific derivatization. This method opens the possibility of investigating the potential implication of these six steroids in the most suitable animal model for neurosteroid-related research. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. HIT'nDRIVE: patient-specific multidriver gene prioritization for precision oncology

    PubMed Central

    Hodzic, Ermin; Sauerwald, Thomas; Dao, Phuong; Wang, Kendric; Yeung, Jake; Anderson, Shawn; Vandin, Fabio; Haffari, Gholamreza; Collins, Colin C.; Sahinalp, S. Cenk

    2017-01-01

    Prioritizing molecular alterations that act as drivers of cancer remains a crucial bottleneck in therapeutic development. Here we introduce HIT'nDRIVE, a computational method that integrates genomic and transcriptomic data to identify a set of patient-specific, sequence-altered genes, with sufficient collective influence over dysregulated transcripts. HIT'nDRIVE aims to solve the “random walk facility location” (RWFL) problem in a gene (or protein) interaction network, which differs from the standard facility location problem by its use of an alternative distance measure: “multihitting time,” the expected length of the shortest random walk from any one of the set of sequence-altered genes to an expression-altered target gene. When applied to 2200 tumors from four major cancer types, HIT'nDRIVE revealed many potentially clinically actionable driver genes. We also demonstrated that it is possible to perform accurate phenotype prediction for tumor samples by only using HIT'nDRIVE-seeded driver gene modules from gene interaction networks. In addition, we identified a number of breast cancer subtype-specific driver modules that are associated with patients’ survival outcome. Furthermore, HIT'nDRIVE, when applied to a large panel of pan-cancer cell lines, accurately predicted drug efficacy using the driver genes and their seeded gene modules. Overall, HIT'nDRIVE may help clinicians contextualize massive multiomics data in therapeutic decision making, enabling widespread implementation of precision oncology. PMID:28768687

  10. Accurate, precise, and efficient theoretical methods to calculate anion-π interaction energies in model structures.

    PubMed

    Mezei, Pál D; Csonka, Gábor I; Ruzsinszky, Adrienn; Sun, Jianwei

    2015-01-13

    A correct description of the anion-π interaction is essential for the design of selective anion receptors and channels and important for advances in the field of supramolecular chemistry. However, it is challenging to do accurate, precise, and efficient calculations of this interaction, which are lacking in the literature. In this article, by testing sets of 20 binary anion-π complexes of fluoride, chloride, bromide, nitrate, or carbonate ions with hexafluorobenzene, 1,3,5-trifluorobenzene, 2,4,6-trifluoro-1,3,5-triazine, or 1,3,5-triazine and 30 ternary π-anion-π' sandwich complexes composed from the same monomers, we suggest domain-based local-pair natural orbital coupled cluster energies extrapolated to the complete basis-set limit as reference values. We give a detailed explanation of the origin of anion-π interactions, using the permanent quadrupole moments, static dipole polarizabilities, and electrostatic potential maps. We use symmetry-adapted perturbation theory (SAPT) to calculate the components of the anion-π interaction energies. We examine the performance of the direct random phase approximation (dRPA), the second-order screened exchange (SOSEX), local-pair natural-orbital (LPNO) coupled electron pair approximation (CEPA), and several dispersion-corrected density functionals (including generalized gradient approximation (GGA), meta-GGA, and double hybrid density functional). The LPNO-CEPA/1 results show the best agreement with the reference results. The dRPA method is only slightly less accurate and precise than the LPNO-CEPA/1, but it is considerably more efficient (6-17 times faster) for the binary complexes studied in this paper. For 30 ternary π-anion-π' sandwich complexes, we give dRPA interaction energies as reference values. The double hybrid functionals are much more efficient but less accurate and precise than dRPA. The dispersion-corrected double hybrid PWPB95-D3(BJ) and B2PLYP-D3(BJ) functionals perform better than the GGA and meta

  11. Advances in Multicollector ICPMS for precise and accurate isotope ratio measurements of Uranium isotopes

    NASA Astrophysics Data System (ADS)

    Bouman, C.; Lloyd, N. S.; Schwieters, J.

    2011-12-01

    The accurate and precise determination of uranium isotopes is challenging, because of the large dynamic range posed by the U isotope abundances and the limited available sample material. Various mass spectrometric techniques are used for the measurement of U isotopes, where TIMS is the most accepted and accurate one. Multicollector inductively coupled plasma mass spectrometry (MC-ICPMS) can offer higher productivity compared to TIMS, but is traditionally limited by low efficiency of sample utilisation. This contribution will discuss progress in MC-ICPMS for detecting 234U, 235U, 236U and 238U in various uranium reference materials from IRMM and NBL. The Thermo Scientific NEPTUNE Plus with Jet Interface offers a modified dry plasma ICP interface using a large interface pump combined with a special set of sample and skimmer cones giving ultimate sensitivity for all elements across the mass range. For uranium, an ion yield of > 3 % was reported previously [1]. The NEPTUNE Plus also offers Multi Ion Counting using discrete dynode electron multipliers as well as two high abundance-sensitivity filters to discriminate against peak tailing effects on 234U and 236U originating from the major uranium beams. These improvements in sensitivity and dynamic range allow accurate measurements of 234U, 235U and 236U abundances on very small samples and at low concentration. In our approach, minor U isotopes 234U and 236U were detected on ion counters with high abundance sensitivity filters, whereas 235U and 238U were detected on Faraday Cups using a high gain current amplifier (10e12 Ohm) for 235U. Precisions and accuracies for 234U and 236U were down to ~1%. For 235U, subpermil levels were reached.

  12. Advanced bioanalytics for precision medicine.

    PubMed

    Roda, Aldo; Michelini, Elisa; Caliceti, Cristiana; Guardigli, Massimo; Mirasoli, Mara; Simoni, Patrizia

    2018-01-01

    Precision medicine is a new paradigm that combines diagnostic, imaging, and analytical tools to produce accurate diagnoses and therapeutic interventions tailored to the individual patient. This approach stands in contrast to the traditional "one size fits all" concept, according to which researchers develop disease treatments and preventions for an "average" patient without considering individual differences. The "one size fits all" concept has led to many ineffective or inappropriate treatments, especially for pathologies such as Alzheimer's disease and cancer. Now, precision medicine is receiving massive funding in many countries, thanks to its social and economic potential in terms of improved disease prevention, diagnosis, and therapy. Bioanalytical chemistry is critical to precision medicine. This is because identifying an appropriate tailored therapy requires researchers to collect and analyze information on each patient's specific molecular biomarkers (e.g., proteins, nucleic acids, and metabolites). In other words, precision diagnostics is not possible without precise bioanalytical chemistry. This Trend article highlights some of the most recent advances, including massive analysis of multilayer omics, and new imaging technique applications suitable for implementing precision medicine. Graphical abstract Precision medicine combines bioanalytical chemistry, molecular diagnostics, and imaging tools for performing accurate diagnoses and selecting optimal therapies for each patient.

  13. Fully automated laboratory and field-portable goniometer used for performing accurate and precise multiangular reflectance measurements

    NASA Astrophysics Data System (ADS)

    Harms, Justin D.; Bachmann, Charles M.; Ambeau, Brittany L.; Faulring, Jason W.; Ruiz Torres, Andres J.; Badura, Gregory; Myers, Emily

    2017-10-01

    Field-portable goniometers are created for a wide variety of applications. Many of these applications require specific types of instruments and measurement schemes and must operate in challenging environments. Therefore, designs are based on the requirements that are specific to the application. We present a field-portable goniometer that was designed for measuring the hemispherical-conical reflectance factor (HCRF) of various soils and low-growing vegetation in austere coastal and desert environments and biconical reflectance factors in laboratory settings. Unlike some goniometers, this system features a requirement for "target-plane tracking" to ensure that measurements can be collected on sloped surfaces, without compromising angular accuracy. The system also features a second upward-looking spectrometer to measure the spatially dependent incoming illumination, an integrated software package to provide full automation, an automated leveling system to ensure a standard frame of reference, a design that minimizes the obscuration due to self-shading to measure the opposition effect, and the ability to record a digital elevation model of the target region. This fully automated and highly mobile system obtains accurate and precise measurements of HCRF in a wide variety of terrain and in less time than most other systems while not sacrificing consistency or repeatability in laboratory environments.

  14. 27 CFR 30.25 - Use of precision specific gravity hydrometers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... gravity hydrometers. 30.25 Section 30.25 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... precision specific gravity hydrometers. The provisions of § 30.23 respecting the care, handling, and use of... specific gravity hydrometers. Specific gravity hydrometers shall be read to the nearest subdivision...

  15. 27 CFR 30.25 - Use of precision specific gravity hydrometers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... gravity hydrometers. 30.25 Section 30.25 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... precision specific gravity hydrometers. The provisions of § 30.23 respecting the care, handling, and use of... specific gravity hydrometers. Specific gravity hydrometers shall be read to the nearest subdivision...

  16. 27 CFR 30.25 - Use of precision specific gravity hydrometers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... gravity hydrometers. 30.25 Section 30.25 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... precision specific gravity hydrometers. The provisions of § 30.23 respecting the care, handling, and use of... specific gravity hydrometers. Specific gravity hydrometers shall be read to the nearest subdivision...

  17. 27 CFR 30.25 - Use of precision specific gravity hydrometers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... gravity hydrometers. 30.25 Section 30.25 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... precision specific gravity hydrometers. The provisions of § 30.23 respecting the care, handling, and use of... specific gravity hydrometers. Specific gravity hydrometers shall be read to the nearest subdivision...

  18. 27 CFR 30.25 - Use of precision specific gravity hydrometers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... gravity hydrometers. 30.25 Section 30.25 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... precision specific gravity hydrometers. The provisions of § 30.23 respecting the care, handling, and use of... specific gravity hydrometers. Specific gravity hydrometers shall be read to the nearest subdivision...

  19. Accurate, Sensitive, and Precise Multiplexed Proteomics Using the Complement Reporter Ion Cluster

    DOE PAGES

    Sonnett, Matthew; Yeung, Eyan; Wuhr, Martin

    2018-03-09

    We present that quantitative analysis of proteomes across multiple time points, organelles, and perturbations is essential for understanding both fundamental biology and disease states. The development of isobaric tags (e.g. TMT) have enabled the simultaneous measurement of peptide abundances across several different conditions. These multiplexed approaches are promising in principle because of advantages in throughput and measurement quality. However, in practice existing multiplexing approaches suffer from key limitations. In its simple implementation (TMT-MS2), measurements are distorted by chemical noise leading to poor measurement accuracy. The current state-of-the-art (TMT-MS3) addresses this, but requires specialized quadrupole-iontrap-Orbitrap instrumentation. The complement reporter ion approachmore » (TMTc) produces high accuracy measurements and is compatible with many more instruments, like quadrupole-Orbitraps. However, the required deconvolution of the TMTc cluster leads to poor measurement precision. Here, we introduce TMTc+, which adds the modeling of the MS2-isolation step into the deconvolution algorithm. The resulting measurements are comparable in precision to TMT-MS3/MS2. The improved duty cycle, and lower filtering requirements make TMTc+ more sensitive than TMT-MS3 and comparable with TMT-MS2. At the same time, unlike TMT-MS2, TMTc+ is exquisitely able to distinguish signal from chemical noise even outperforming TMT-MS3. Lastly, we compare TMTc+ to quantitative label-free proteomics of total HeLa lysate and find that TMTc+ quantifies 7.8k versus 3.9k proteins in a 5-plex sample. At the same time the median coefficient of variation improves from 13% to 4%. Furthermore, TMTc+ advances quantitative proteomics by enabling accurate, sensitive, and precise multiplexed experiments on more commonly used instruments.« less

  20. Accurate, Sensitive, and Precise Multiplexed Proteomics Using the Complement Reporter Ion Cluster

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

    Sonnett, Matthew; Yeung, Eyan; Wuhr, Martin

    We present that quantitative analysis of proteomes across multiple time points, organelles, and perturbations is essential for understanding both fundamental biology and disease states. The development of isobaric tags (e.g. TMT) have enabled the simultaneous measurement of peptide abundances across several different conditions. These multiplexed approaches are promising in principle because of advantages in throughput and measurement quality. However, in practice existing multiplexing approaches suffer from key limitations. In its simple implementation (TMT-MS2), measurements are distorted by chemical noise leading to poor measurement accuracy. The current state-of-the-art (TMT-MS3) addresses this, but requires specialized quadrupole-iontrap-Orbitrap instrumentation. The complement reporter ion approachmore » (TMTc) produces high accuracy measurements and is compatible with many more instruments, like quadrupole-Orbitraps. However, the required deconvolution of the TMTc cluster leads to poor measurement precision. Here, we introduce TMTc+, which adds the modeling of the MS2-isolation step into the deconvolution algorithm. The resulting measurements are comparable in precision to TMT-MS3/MS2. The improved duty cycle, and lower filtering requirements make TMTc+ more sensitive than TMT-MS3 and comparable with TMT-MS2. At the same time, unlike TMT-MS2, TMTc+ is exquisitely able to distinguish signal from chemical noise even outperforming TMT-MS3. Lastly, we compare TMTc+ to quantitative label-free proteomics of total HeLa lysate and find that TMTc+ quantifies 7.8k versus 3.9k proteins in a 5-plex sample. At the same time the median coefficient of variation improves from 13% to 4%. Furthermore, TMTc+ advances quantitative proteomics by enabling accurate, sensitive, and precise multiplexed experiments on more commonly used instruments.« less

  1. Transthoracic echocardiography: an accurate and precise method for estimating cardiac output in the critically ill patient.

    PubMed

    Mercado, Pablo; Maizel, Julien; Beyls, Christophe; Titeca-Beauport, Dimitri; Joris, Magalie; Kontar, Loay; Riviere, Antoine; Bonef, Olivier; Soupison, Thierry; Tribouilloy, Christophe; de Cagny, Bertrand; Slama, Michel

    2017-06-09

    % yielded a sensitivity of 88% and specificity of 66% for detecting a ΔCO-PAC of more than 10%. In critically ill mechanically ventilated patients, CO-TTE is an accurate and precise method for estimating CO. Furthermore, CO-TTE can accurately track variations in CO.

  2. Precisely and Accurately Inferring Single-Molecule Rate Constants

    PubMed Central

    Kinz-Thompson, Colin D.; Bailey, Nevette A.; Gonzalez, Ruben L.

    2017-01-01

    The kinetics of biomolecular systems can be quantified by calculating the stochastic rate constants that govern the biomolecular state versus time trajectories (i.e., state trajectories) of individual biomolecules. To do so, the experimental signal versus time trajectories (i.e., signal trajectories) obtained from observing individual biomolecules are often idealized to generate state trajectories by methods such as thresholding or hidden Markov modeling. Here, we discuss approaches for idealizing signal trajectories and calculating stochastic rate constants from the resulting state trajectories. Importantly, we provide an analysis of how the finite length of signal trajectories restrict the precision of these approaches, and demonstrate how Bayesian inference-based versions of these approaches allow rigorous determination of this precision. Similarly, we provide an analysis of how the finite lengths and limited time resolutions of signal trajectories restrict the accuracy of these approaches, and describe methods that, by accounting for the effects of the finite length and limited time resolution of signal trajectories, substantially improve this accuracy. Collectively, therefore, the methods we consider here enable a rigorous assessment of the precision, and a significant enhancement of the accuracy, with which stochastic rate constants can be calculated from single-molecule signal trajectories. PMID:27793280

  3. Toward accurate and precise estimates of lion density.

    PubMed

    Elliot, Nicholas B; Gopalaswamy, Arjun M

    2017-08-01

    Reliable estimates of animal density are fundamental to understanding ecological processes and population dynamics. Furthermore, their accuracy is vital to conservation because wildlife authorities rely on estimates to make decisions. However, it is notoriously difficult to accurately estimate density for wide-ranging carnivores that occur at low densities. In recent years, significant progress has been made in density estimation of Asian carnivores, but the methods have not been widely adapted to African carnivores, such as lions (Panthera leo). Although abundance indices for lions may produce poor inferences, they continue to be used to estimate density and inform management and policy. We used sighting data from a 3-month survey and adapted a Bayesian spatially explicit capture-recapture (SECR) model to estimate spatial lion density in the Maasai Mara National Reserve and surrounding conservancies in Kenya. Our unstructured spatial capture-recapture sampling design incorporated search effort to explicitly estimate detection probability and density on a fine spatial scale, making our approach robust in the context of varying detection probabilities. Overall posterior mean lion density was estimated to be 17.08 (posterior SD 1.310) lions >1 year old/100 km 2 , and the sex ratio was estimated at 2.2 females to 1 male. Our modeling framework and narrow posterior SD demonstrate that SECR methods can produce statistically rigorous and precise estimates of population parameters, and we argue that they should be favored over less reliable abundance indices. Furthermore, our approach is flexible enough to incorporate different data types, which enables robust population estimates over relatively short survey periods in a variety of systems. Trend analyses are essential to guide conservation decisions but are frequently based on surveys of differing reliability. We therefore call for a unified framework to assess lion numbers in key populations to improve management and

  4. Precision manometer gauge

    DOEpatents

    McPherson, Malcolm J.; Bellman, Robert A.

    1984-01-01

    A precision manometer gauge which locates a zero height and a measured height of liquid using an open tube in communication with a reservoir adapted to receive the pressure to be measured. The open tube has a reference section carried on a positioning plate which is moved vertically with machine tool precision. Double scales are provided to read the height of the positioning plate accurately, the reference section being inclined for accurate meniscus adjustment, and means being provided to accurately locate a zero or reference position.

  5. Precision manometer gauge

    DOEpatents

    McPherson, M.J.; Bellman, R.A.

    1982-09-27

    A precision manometer gauge which locates a zero height and a measured height of liquid using an open tube in communication with a reservoir adapted to receive the pressure to be measured. The open tube has a reference section carried on a positioning plate which is moved vertically with machine tool precision. Double scales are provided to read the height of the positioning plate accurately, the reference section being inclined for accurate meniscus adjustment, and means being provided to accurately locate a zero or reference position.

  6. Safe and accurate midcervical pedicle screw insertion procedure with the patient-specific screw guide template system.

    PubMed

    Kaneyama, Shuichi; Sugawara, Taku; Sumi, Masatoshi

    2015-03-15

    Clinical trial for midcervical pedicle screw insertion using a novel patient-specific intraoperative screw guiding device. To evaluate the availability of the "Screw Guide Template" (SGT) system for insertion of midcervical pedicle screws. Despite many efforts for accurate midcervical pedicle screw insertion, there still remain unacceptable rate of screw malpositioning that might cause neurovascular injuries. We developed patient-specific SGT system for safe and accurate intraoperative screw navigation tool and have reported its availability for the screw insertion to C2 vertebra and thoracic spine. Preoperatively, the bone image on computed tomography was analyzed and the trajectories of the screws were designed in 3-dimensional format. Three types of templates were created for each lamina: location template, drill guide template, and screw guide template. During the operations, after engaging the templates directly with the laminae, drilling, tapping, and screwing were performed with each template. We placed 80 midcervical pedicle screws for 20 patients. The accuracy and safety of the screw insertion by SGT system were evaluated using postoperative computed tomographic scan by calculation of screw deviation from the preplanned trajectory and evaluation of screw breach of pedicle wall. All templates fitted the laminae and screw navigation procedures proceeded uneventfully. All screws were inserted accurately with the mean screw deviation from planned trajectory of 0.29 ± 0.31 mm and no neurovascular complication was experienced. We demonstrated that our SGT system could support the precise screw insertion in midcervical pedicle. SGT prescribes the safe screw trajectory in a 3-dimensional manner and the templates fit and lock directly to the target laminae, which prevents screwing error along with the change of spinal alignment during the surgery. These advantages of the SGT system guarantee the high accuracy in screw insertion, which allowed surgeons to insert

  7. Is digital photography an accurate and precise method for measuring range of motion of the hip and knee?

    PubMed

    Russo, Russell R; Burn, Matthew B; Ismaily, Sabir K; Gerrie, Brayden J; Han, Shuyang; Alexander, Jerry; Lenherr, Christopher; Noble, Philip C; Harris, Joshua D; McCulloch, Patrick C

    2017-09-07

    Accurate measurements of knee and hip motion are required for management of musculoskeletal pathology. The purpose of this investigation was to compare three techniques for measuring motion at the hip and knee. The authors hypothesized that digital photography would be equivalent in accuracy and show higher precision compared to the other two techniques. Using infrared motion capture analysis as the reference standard, hip flexion/abduction/internal rotation/external rotation and knee flexion/extension were measured using visual estimation, goniometry, and photography on 10 fresh frozen cadavers. These measurements were performed by three physical therapists and three orthopaedic surgeons. Accuracy was defined by the difference from the reference standard, while precision was defined by the proportion of measurements within either 5° or 10°. Analysis of variance (ANOVA), t-tests, and chi-squared tests were used. Although two statistically significant differences were found in measurement accuracy between the three techniques, neither of these differences met clinical significance (difference of 1.4° for hip abduction and 1.7° for the knee extension). Precision of measurements was significantly higher for digital photography than: (i) visual estimation for hip abduction and knee extension, and (ii) goniometry for knee extension only. There was no clinically significant difference in measurement accuracy between the three techniques for hip and knee motion. Digital photography only showed higher precision for two joint motions (hip abduction and knee extension). Overall digital photography shows equivalent accuracy and near-equivalent precision to visual estimation and goniometry.

  8. Five critical elements to ensure the precision medicine.

    PubMed

    Chen, Chengshui; He, Mingyan; Zhu, Yichun; Shi, Lin; Wang, Xiangdong

    2015-06-01

    The precision medicine as a new emerging area and therapeutic strategy has occurred and was practiced in the individual and brought unexpected successes, and gained high attentions from professional and social aspects as a new path to improve the treatment and prognosis of patients. There will be a number of new components to appear or be discovered, of which clinical bioinformatics integrates clinical phenotypes and informatics with bioinformatics, computational science, mathematics, and systems biology. In addition to those tools, precision medicine calls more accurate and repeatable methodologies for the identification and validation of gene discovery. Precision medicine will bring more new therapeutic strategies, drug discovery and development, and gene-oriented treatment. There is an urgent need to identify and validate disease-specific, mechanism-based, or epigenetics-dependent biomarkers to monitor precision medicine, and develop "precision" regulations to guard the application of precision medicine.

  9. Is digital photography an accurate and precise method for measuring range of motion of the shoulder and elbow?

    PubMed

    Russo, Russell R; Burn, Matthew B; Ismaily, Sabir K; Gerrie, Brayden J; Han, Shuyang; Alexander, Jerry; Lenherr, Christopher; Noble, Philip C; Harris, Joshua D; McCulloch, Patrick C

    2018-03-01

    Accurate measurements of shoulder and elbow motion are required for the management of musculoskeletal pathology. The purpose of this investigation was to compare three techniques for measuring motion. The authors hypothesized that digital photography would be equivalent in accuracy and show higher precision compared to the other two techniques. Using infrared motion capture analysis as the reference standard, shoulder flexion/abduction/internal rotation/external rotation and elbow flexion/extension were measured using visual estimation, goniometry, and digital photography on 10 fresh frozen cadavers. These measurements were performed by three physical therapists and three orthopaedic surgeons. Accuracy was defined by the difference from the reference standard (motion capture analysis), while precision was defined by the proportion of measurements within the authors' definition of clinical significance (10° for all motions except for elbow extension where 5° was used). Analysis of variance (ANOVA), t-tests, and chi-squared tests were used. Although statistically significant differences were found in measurement accuracy between the three techniques, none of these differences met the authors' definition of clinical significance. Precision of the measurements was significantly higher for both digital photography (shoulder abduction [93% vs. 74%, p < 0.001], shoulder internal rotation [97% vs. 83%, p = 0.001], and elbow flexion [93% vs. 65%, p < 0.001]) and goniometry (shoulder abduction [92% vs. 74%, p < 0.001] and shoulder internal rotation [94% vs. 83%, p = 0.008]) than visual estimation. Digital photography was more precise than goniometry for measurements of elbow flexion only [93% vs. 76%, p < 0.001]. There was no clinically significant difference in measurement accuracy between the three techniques for shoulder and elbow motion. Digital photography showed higher measurement precision compared to visual estimation for shoulder abduction, shoulder

  10. Deficits in Coordinative Bimanual Timing Precision in Children with Specific Language Impairment

    ERIC Educational Resources Information Center

    Vuolo, Janet; Goffman, Lisa; Zelaznik, Howard N.

    2017-01-01

    Purpose: Our objective was to delineate components of motor performance in specific language impairment (SLI); specifically, whether deficits in timing precision in one effector (unimanual tapping) and in two effectors (bimanual clapping) are observed in young children with SLI. Method: Twenty-seven 4- to 5-year-old children with SLI and 21…

  11. Using High-Precision Specific Gravity Measurements to Study Minerals in Undergraduate Geoscience Courses

    ERIC Educational Resources Information Center

    Brandriss, Mark E.

    2010-01-01

    This article describes ways to incorporate high-precision measurements of the specific gravities of minerals into undergraduate courses in mineralogy and physical geology. Most traditional undergraduate laboratory methods of measuring specific gravity are suitable only for unusually large samples, which severely limits their usefulness for student…

  12. Nanomaterials for Cancer Precision Medicine.

    PubMed

    Wang, Yilong; Sun, Shuyang; Zhang, Zhiyuan; Shi, Donglu

    2018-04-01

    Medical science has recently advanced to the point where diagnosis and therapeutics can be carried out with high precision, even at the molecular level. A new field of "precision medicine" has consequently emerged with specific clinical implications and challenges that can be well-addressed by newly developed nanomaterials. Here, a nanoscience approach to precision medicine is provided, with a focus on cancer therapy, based on a new concept of "molecularly-defined cancers." "Next-generation sequencing" is introduced to identify the oncogene that is responsible for a class of cancers. This new approach is fundamentally different from all conventional cancer therapies that rely on diagnosis of the anatomic origins where the tumors are found. To treat cancers at molecular level, a recently developed "microRNA replacement therapy" is applied, utilizing nanocarriers, in order to regulate the driver oncogene, which is the core of cancer precision therapeutics. Furthermore, the outcome of the nanomediated oncogenic regulation has to be accurately assessed by the genetically characterized, patient-derived xenograft models. Cancer therapy in this fashion is a quintessential example of precision medicine, presenting many challenges to the materials communities with new issues in structural design, surface functionalization, gene/drug storage and delivery, cell targeting, and medical imaging. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Technologies That Enable Accurate and Precise Nano- to Milliliter-Scale Liquid Dispensing of Aqueous Reagents Using Acoustic Droplet Ejection.

    PubMed

    Sackmann, Eric K; Majlof, Lars; Hahn-Windgassen, Annett; Eaton, Brent; Bandzava, Temo; Daulton, Jay; Vandenbroucke, Arne; Mock, Matthew; Stearns, Richard G; Hinkson, Stephen; Datwani, Sammy S

    2016-02-01

    Acoustic liquid handling uses high-frequency acoustic signals that are focused on the surface of a fluid to eject droplets with high accuracy and precision for various life science applications. Here we present a multiwell source plate, the Echo Qualified Reservoir (ER), which can acoustically transfer over 2.5 mL of fluid per well in 25-nL increments using an Echo 525 liquid handler. We demonstrate two Labcyte technologies-Dynamic Fluid Analysis (DFA) methods and a high-voltage (HV) grid-that are required to maintain accurate and precise fluid transfers from the ER at this volume scale. DFA methods were employed to dynamically assess the energy requirements of the fluid and adjust the acoustic ejection parameters to maintain a constant velocity droplet. Furthermore, we demonstrate that the HV grid enhances droplet velocity and coalescence at the destination plate. These technologies enabled 5-µL per destination well transfers to a 384-well plate, with accuracy and precision values better than 4%. Last, we used the ER and Echo 525 liquid handler to perform a quantitative polymerase chain reaction (qPCR) assay to demonstrate an application that benefits from the flexibility and larger volume capabilities of the ER. © 2015 Society for Laboratory Automation and Screening.

  14. Deficits in Coordinative Bimanual Timing Precision in Children With Specific Language Impairment

    PubMed Central

    Goffman, Lisa; Zelaznik, Howard N.

    2017-01-01

    Purpose Our objective was to delineate components of motor performance in specific language impairment (SLI); specifically, whether deficits in timing precision in one effector (unimanual tapping) and in two effectors (bimanual clapping) are observed in young children with SLI. Method Twenty-seven 4- to 5-year-old children with SLI and 21 age-matched peers with typical language development participated. All children engaged in a unimanual tapping and a bimanual clapping timing task. Standard measures of language and motor performance were also obtained. Results No group differences in timing variability were observed in the unimanual tapping task. However, compared with typically developing peers, children with SLI were more variable in their timing precision in the bimanual clapping task. Nine of the children with SLI performed greater than 1 SD below the mean on a standardized motor assessment. The children with low motor performance showed the same profile as observed across all children with SLI, with unaffected unimanual and impaired bimanual timing precision. Conclusions Although unimanual timing is unaffected, children with SLI show a deficit in timing that requires bimanual coordination. We propose that the timing deficits observed in children with SLI are associated with the increased demands inherent in bimanual performance. PMID:28174821

  15. A robust statistical estimation (RoSE) algorithm jointly recovers the 3D location and intensity of single molecules accurately and precisely

    NASA Astrophysics Data System (ADS)

    Mazidi, Hesam; Nehorai, Arye; Lew, Matthew D.

    2018-02-01

    In single-molecule (SM) super-resolution microscopy, the complexity of a biological structure, high molecular density, and a low signal-to-background ratio (SBR) may lead to imaging artifacts without a robust localization algorithm. Moreover, engineered point spread functions (PSFs) for 3D imaging pose difficulties due to their intricate features. We develop a Robust Statistical Estimation algorithm, called RoSE, that enables joint estimation of the 3D location and photon counts of SMs accurately and precisely using various PSFs under conditions of high molecular density and low SBR.

  16. Precise dielectric property measurements and E-field probe calibration for specific absorption rate measurements using a rectangular waveguide

    PubMed Central

    Hakim, B M; Beard, B B; Davis, C C

    2018-01-01

    Specific absorption rate (SAR) measurements require accurate calculations of the dielectric properties of tissue-equivalent liquids and associated calibration of E-field probes. We developed a precise tissue-equivalent dielectric measurement and E-field probe calibration system. The system consists of a rectangular waveguide, electric field probe, and data control and acquisition system. Dielectric properties are calculated using the field attenuation factor inside the tissue-equivalent liquid and power reflectance inside the waveguide at the air/dielectric-slab interface. Calibration factors were calculated using isotropicity measurements of the E-field probe. The frequencies used are 900 MHz and 1800 MHz. The uncertainties of the measured values are within ±3%, at the 95% confidence level. Using the same waveguide for dielectric measurements as well as calibrating E-field probes used in SAR assessments eliminates a source of uncertainty. Moreover, we clearly identified the system parameters that affect the overall uncertainty of the measurement system. PMID:29520129

  17. Exploiting microRNA Specificity and Selectivity: Paving a Sustainable Path Towards Precision Medicine.

    PubMed

    Santulli, Gaetano

    2015-01-01

    In his State of the Union address before both chambers of the US Congress, President Barack Obama called for increased investment in US infrastructure and research and announced the launch of a new Precision Medicine Initiative, aiming to accelerate biomedical discovery. Due to their well-established selectivity and specificity, microRNAs can represent a useful tool, both in diagnosis and therapy, in forging the path towards the achievement of precision medicine. This introductory chapter represents a guide for the Reader in examining the functional roles of microRNAs in the most diverse aspects of clinical practice, which will be explored in this third volume of the microRNA trilogy.

  18. Exploiting microRNA Specificity and Selectivity: Paving a Sustainable Path Towards Precision Medicine

    PubMed Central

    2016-01-01

    In his State of the Union address before both chambers of the US Congress, President Barack Obama called for increased investment in US infrastructure and research and announced the launch of a new Precision Medicine Initiative, aiming to accelerate biomedical discovery. Due to their well-established selectivity and specificity, microRNAs can represent a useful tool, both in diagnosis and therapy, in forging the path towards the achievement of precision medicine. This introductory chapter represents a guide for the Reader in examining the functional roles of microRNAs in the most diverse aspects of clinical practice, which will be explored in this third volume of the microRNA trilogy. PMID:26663175

  19. Gene mutation-based and specific therapies in precision medicine.

    PubMed

    Wang, Xiangdong

    2016-04-01

    Precision medicine has been initiated and gains more and more attention from preclinical and clinical scientists. A number of key elements or critical parts in precision medicine have been described and emphasized to establish a systems understanding of precision medicine. The principle of precision medicine is to treat patients on the basis of genetic alterations after gene mutations are identified, although questions and challenges still remain before clinical application. Therapeutic strategies of precision medicine should be considered according to gene mutation, after biological and functional mechanisms of mutated gene expression or epigenetics, or the correspondent protein, are clearly validated. It is time to explore and develop a strategy to target and correct mutated genes by direct elimination, restoration, correction or repair of mutated sequences/genes. Nevertheless, there are still numerous challenges to integrating widespread genomic testing into individual cancer therapies and into decision making for one or another treatment. There are wide-ranging and complex issues to be solved before precision medicine becomes clinical reality. Thus, the precision medicine can be considered as an extension and part of clinical and translational medicine, a new alternative of clinical therapies and strategies, and have an important impact on disease cures and patient prognoses. © 2015 The Author. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  20. Precision Timing of PSR J0437-4715: An Accurate Pulsar Distance, a High Pulsar Mass, and a Limit on the Variation of Newton's Gravitational Constant

    NASA Astrophysics Data System (ADS)

    Verbiest, J. P. W.; Bailes, M.; van Straten, W.; Hobbs, G. B.; Edwards, R. T.; Manchester, R. N.; Bhat, N. D. R.; Sarkissian, J. M.; Jacoby, B. A.; Kulkarni, S. R.

    2008-05-01

    Analysis of 10 years of high-precision timing data on the millisecond pulsar PSR J0437-4715 has resulted in a model-independent kinematic distance based on an apparent orbital period derivative, dot Pb , determined at the 1.5% level of precision (Dk = 157.0 +/- 2.4 pc), making it one of the most accurate stellar distance estimates published to date. The discrepancy between this measurement and a previously published parallax distance estimate is attributed to errors in the DE200 solar system ephemerides. The precise measurement of dot Pb allows a limit on the variation of Newton's gravitational constant, |Ġ/G| <= 23 × 10-12 yr-1. We also constrain any anomalous acceleration along the line of sight to the pulsar to |a⊙/c| <= 1.5 × 10-18 s-1 at 95% confidence, and derive a pulsar mass, mpsr = 1.76 +/- 0.20 M⊙, one of the highest estimates so far obtained.

  1. Using hyperspectral data in precision farming applications

    USDA-ARS?s Scientific Manuscript database

    Precision farming practices such as variable rate applications of fertilizer and agricultural chemicals require accurate field variability mapping. This chapter investigated the value of hyperspectral remote sensing in providing useful information for five applications of precision farming: (a) Soil...

  2. Precision grid and hand motion for accurate needle insertion in brachytherapy

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

    McGill, Carl S.; Schwartz, Jonathon A.; Moore, Jason Z.

    2011-08-15

    Purpose: In prostate brachytherapy, a grid is used to guide a needle tip toward a preplanned location within the tissue. During insertion, the needle deflects en route resulting in target misplacement. In this paper, 18-gauge needle insertion experiments into phantom were performed to test effects of three parameters, which include the clearance between the grid hole and needle, the thickness of the grid, and the needle insertion speed. Measurement apparatus that consisted of two datum surfaces and digital depth gauge was developed to quantify needle deflections. Methods: The gauge repeatability and reproducibility (GR and R) test was performed on themore » measurement apparatus, and it proved to be capable of measuring a 2 mm tolerance from the target. Replicated experiments were performed on a 2{sup 3} factorial design (three parameters at two levels) and analysis included averages and standard deviation along with an analysis of variance (ANOVA) to find significant single and two-way interaction factors. Results: Results showed that grid with tight clearance hole and slow needle speed increased precision and accuracy of needle insertion. The tight grid was vital to enhance precision and accuracy of needle insertion for both slow and fast insertion speed; additionally, at slow speed the tight, thick grid improved needle precision and accuracy. Conclusions: In summary, the tight grid is important, regardless of speed. The grid design, which shows the capability to reduce the needle deflection in brachytherapy procedures, can potentially be implemented in the brachytherapy procedure.« less

  3. Using Precision in STEM Language: A Qualitative Look

    ERIC Educational Resources Information Center

    Capraro, Mary M.; Bicer, Ali; Grant, Melva R.; Lincoln, Yvonna S.

    2017-01-01

    Teachers need to develop a variety of pedagogical strategies that can encourage precise and accurate communication--an extremely important 21st century skill. Precision with STEM oral language is essential. Emphasizing oral communication with precise language in combination with increased spatial skills with modeling can improve the chances of…

  4. An Image-Based Algorithm for Precise and Accurate High Throughput Assessment of Drug Activity against the Human Parasite Trypanosoma cruzi

    PubMed Central

    Moraes, Carolina Borsoi; Yang, Gyongseon; Kang, Myungjoo; Freitas-Junior, Lucio H.; Hansen, Michael A. E.

    2014-01-01

    We present a customized high content (image-based) and high throughput screening algorithm for the quantification of Trypanosoma cruzi infection in host cells. Based solely on DNA staining and single-channel images, the algorithm precisely segments and identifies the nuclei and cytoplasm of mammalian host cells as well as the intracellular parasites infecting the cells. The algorithm outputs statistical parameters including the total number of cells, number of infected cells and the total number of parasites per image, the average number of parasites per infected cell, and the infection ratio (defined as the number of infected cells divided by the total number of cells). Accurate and precise estimation of these parameters allow for both quantification of compound activity against parasites, as well as the compound cytotoxicity, thus eliminating the need for an additional toxicity-assay, hereby reducing screening costs significantly. We validate the performance of the algorithm using two known drugs against T.cruzi: Benznidazole and Nifurtimox. Also, we have checked the performance of the cell detection with manual inspection of the images. Finally, from the titration of the two compounds, we confirm that the algorithm provides the expected half maximal effective concentration (EC50) of the anti-T. cruzi activity. PMID:24503652

  5. Robotic-Arm Assisted Total Knee Arthroplasty Demonstrated Greater Accuracy and Precision to Plan Compared with Manual Techniques.

    PubMed

    Hampp, Emily L; Chughtai, Morad; Scholl, Laura Y; Sodhi, Nipun; Bhowmik-Stoker, Manoshi; Jacofsky, David J; Mont, Michael A

    2018-05-01

    This study determined if robotic-arm assisted total knee arthroplasty (RATKA) allows for more accurate and precise bone cuts and component position to plan compared with manual total knee arthroplasty (MTKA). Specifically, we assessed the following: (1) final bone cuts, (2) final component position, and (3) a potential learning curve for RATKA. On six cadaver specimens (12 knees), a MTKA and RATKA were performed on the left and right knees, respectively. Bone-cut and final-component positioning errors relative to preoperative plans were compared. Median errors and standard deviations (SDs) in the sagittal, coronal, and axial planes were compared. Median values of the absolute deviation from plan defined the accuracy to plan. SDs described the precision to plan. RATKA bone cuts were as or more accurate to plan based on nominal median values in 11 out of 12 measurements. RATKA bone cuts were more precise to plan in 8 out of 12 measurements ( p  ≤ 0.05). RATKA final component positions were as or more accurate to plan based on median values in five out of five measurements. RATKA final component positions were more precise to plan in four out of five measurements ( p  ≤ 0.05). Stacked error results from all cuts and implant positions for each specimen in procedural order showed that RATKA error was less than MTKA error. Although this study analyzed a small number of cadaver specimens, there were clear differences that separated these two groups. When compared with MTKA, RATKA demonstrated more accurate and precise bone cuts and implant positioning to plan. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  6. Accurate time delay technology in simulated test for high precision laser range finder

    NASA Astrophysics Data System (ADS)

    Chen, Zhibin; Xiao, Wenjian; Wang, Weiming; Xue, Mingxi

    2015-10-01

    With the continuous development of technology, the ranging accuracy of pulsed laser range finder (LRF) is higher and higher, so the maintenance demand of LRF is also rising. According to the dominant ideology of "time analog spatial distance" in simulated test for pulsed range finder, the key of distance simulation precision lies in the adjustable time delay. By analyzing and comparing the advantages and disadvantages of fiber and circuit delay, a method was proposed to improve the accuracy of the circuit delay without increasing the count frequency of the circuit. A high precision controllable delay circuit was designed by combining the internal delay circuit and external delay circuit which could compensate the delay error in real time. And then the circuit delay accuracy could be increased. The accuracy of the novel circuit delay methods proposed in this paper was actually measured by a high sampling rate oscilloscope actual measurement. The measurement result shows that the accuracy of the distance simulated by the circuit delay is increased from +/- 0.75m up to +/- 0.15m. The accuracy of the simulated distance is greatly improved in simulated test for high precision pulsed range finder.

  7. Fixed-Wing Micro Aerial Vehicle for Accurate Corridor Mapping

    NASA Astrophysics Data System (ADS)

    Rehak, M.; Skaloud, J.

    2015-08-01

    In this study we present a Micro Aerial Vehicle (MAV) equipped with precise position and attitude sensors that together with a pre-calibrated camera enables accurate corridor mapping. The design of the platform is based on widely available model components to which we integrate an open-source autopilot, customized mass-market camera and navigation sensors. We adapt the concepts of system calibration from larger mapping platforms to MAV and evaluate them practically for their achievable accuracy. We present case studies for accurate mapping without ground control points: first for a block configuration, later for a narrow corridor. We evaluate the mapping accuracy with respect to checkpoints and digital terrain model. We show that while it is possible to achieve pixel (3-5 cm) mapping accuracy in both cases, precise aerial position control is sufficient for block configuration, the precise position and attitude control is required for corridor mapping.

  8. Accounting for stimulus-specific variation in precision reveals a discrete capacity limit in visual working memory

    PubMed Central

    Pratte, Michael S.; Park, Young Eun; Rademaker, Rosanne L.; Tong, Frank

    2016-01-01

    If we view a visual scene that contains many objects, then momentarily close our eyes, some details persist while others seem to fade. Discrete models of visual working memory (VWM) assume that only a few items can be actively maintained in memory, beyond which pure guessing will emerge. Alternatively, continuous resource models assume that all items in a visual scene can be stored with some precision. Distinguishing between these competing models is challenging, however, as resource models that allow for stochastically variable precision (across items and trials) can produce error distributions that resemble random guessing behavior. Here, we evaluated the hypothesis that a major source of variability in VWM performance arises from systematic variation in precision across the stimuli themselves; such stimulus-specific variability can be incorporated into both discrete-capacity and variable-precision resource models. Participants viewed multiple oriented gratings, and then reported the orientation of a cued grating from memory. When modeling the overall distribution of VWM errors, we found that the variable-precision resource model outperformed the discrete model. However, VWM errors revealed a pronounced “oblique effect”, with larger errors for oblique than cardinal orientations. After this source of variability was incorporated into both models, we found that the discrete model provided a better account of VWM errors. Our results demonstrate that variable precision across the stimulus space can lead to an unwarranted advantage for resource models that assume stochastically variable precision. When these deterministic sources are adequately modeled, human working memory performance reveals evidence of a discrete capacity limit. PMID:28004957

  9. Accounting for stimulus-specific variation in precision reveals a discrete capacity limit in visual working memory.

    PubMed

    Pratte, Michael S; Park, Young Eun; Rademaker, Rosanne L; Tong, Frank

    2017-01-01

    If we view a visual scene that contains many objects, then momentarily close our eyes, some details persist while others seem to fade. Discrete models of visual working memory (VWM) assume that only a few items can be actively maintained in memory, beyond which pure guessing will emerge. Alternatively, continuous resource models assume that all items in a visual scene can be stored with some precision. Distinguishing between these competing models is challenging, however, as resource models that allow for stochastically variable precision (across items and trials) can produce error distributions that resemble random guessing behavior. Here, we evaluated the hypothesis that a major source of variability in VWM performance arises from systematic variation in precision across the stimuli themselves; such stimulus-specific variability can be incorporated into both discrete-capacity and variable-precision resource models. Participants viewed multiple oriented gratings, and then reported the orientation of a cued grating from memory. When modeling the overall distribution of VWM errors, we found that the variable-precision resource model outperformed the discrete model. However, VWM errors revealed a pronounced "oblique effect," with larger errors for oblique than cardinal orientations. After this source of variability was incorporated into both models, we found that the discrete model provided a better account of VWM errors. Our results demonstrate that variable precision across the stimulus space can lead to an unwarranted advantage for resource models that assume stochastically variable precision. When these deterministic sources are adequately modeled, human working memory performance reveals evidence of a discrete capacity limit. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  10. Precision Muonium Spectroscopy

    NASA Astrophysics Data System (ADS)

    Jungmann, Klaus P.

    2016-09-01

    The muonium atom is the purely leptonic bound state of a positive muon and an electron. It has a lifetime of 2.2 µs. The absence of any known internal structure provides for precision experiments to test fundamental physics theories and to determine accurate values of fundamental constants. In particular ground state hyperfine structure transitions can be measured by microwave spectroscopy to deliver the muon magnetic moment. The frequency of the 1s-2s transition in the hydrogen-like atom can be determined with laser spectroscopy to obtain the muon mass. With such measurements fundamental physical interactions, in particular quantum electrodynamics, can also be tested at highest precision. The results are important input parameters for experiments on the muon magnetic anomaly. The simplicity of the atom enables further precise experiments, such as a search for muonium-antimuonium conversion for testing charged lepton number conservation and searches for possible antigravity of muons and dark matter.

  11. Site-specific recombination for precise and clean transgene integration in plant genome. In: Touraev, A., Citovsky, V., Tzfira, T., Editors of book. Plant Transformation Technologies.

    USDA-ARS?s Scientific Manuscript database

    Plant Transformation Technologies is a comprehensive, authoritative book focusing on cutting-edge plant biotechnologies, offering in-depth, forward-looking information on methods for controlled and accurate genetic engineering. In response to ever-increasing pressure for precise and efficient integr...

  12. Profitable capitation requires accurate costing.

    PubMed

    West, D A; Hicks, L L; Balas, E A; West, T D

    1996-01-01

    In the name of costing accuracy, nurses are asked to track inventory use on per treatment basis when more significant costs, such as general overhead and nursing salaries, are usually allocated to patients or treatments on an average cost basis. Accurate treatment costing and financial viability require analysis of all resources actually consumed in treatment delivery, including nursing services and inventory. More precise costing information enables more profitable decisions as is demonstrated by comparing the ratio-of-cost-to-treatment method (aggregate costing) with alternative activity-based costing methods (ABC). Nurses must participate in this costing process to assure that capitation bids are based upon accurate costs rather than simple averages.

  13. Calibrating GPS With TWSTFT For Accurate Time Transfer

    DTIC Science & Technology

    2008-12-01

    40th Annual Precise Time and Time Interval (PTTI) Meeting 577 CALIBRATING GPS WITH TWSTFT FOR ACCURATE TIME TRANSFER Z. Jiang1 and...primary time transfer techniques are GPS and TWSTFT (Two-Way Satellite Time and Frequency Transfer, TW for short). 83% of UTC time links are...Calibrating GPS With TWSTFT For Accurate Time Transfer 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT

  14. Precision medicine for psychopharmacology: a general introduction.

    PubMed

    Shin, Cheolmin; Han, Changsu; Pae, Chi-Un; Patkar, Ashwin A

    2016-07-01

    Precision medicine is an emerging medical model that can provide accurate diagnoses and tailored therapeutic strategies for patients based on data pertaining to genes, microbiomes, environment, family history and lifestyle. Here, we provide basic information about precision medicine and newly introduced concepts, such as the precision medicine ecosystem and big data processing, and omics technologies including pharmacogenomics, pharamacometabolomics, pharmacoproteomics, pharmacoepigenomics, connectomics and exposomics. The authors review the current state of omics in psychiatry and the future direction of psychopharmacology as it moves towards precision medicine. Expert commentary: Advances in precision medicine have been facilitated by achievements in multiple fields, including large-scale biological databases, powerful methods for characterizing patients (such as genomics, proteomics, metabolomics, diverse cellular assays, and even social networks and mobile health technologies), and computer-based tools for analyzing large amounts of data.

  15. Are Currently Available Wearable Devices for Activity Tracking and Heart Rate Monitoring Accurate, Precise, and Medically Beneficial?

    PubMed Central

    El-Amrawy, Fatema

    2015-01-01

    Objectives The new wave of wireless technologies, fitness trackers, and body sensor devices can have great impact on healthcare systems and the quality of life. However, there have not been enough studies to prove the accuracy and precision of these trackers. The objective of this study was to evaluate the accuracy, precision, and overall performance of seventeen wearable devices currently available compared with direct observation of step counts and heart rate monitoring. Methods Each participant in this study used three accelerometers at a time, running the three corresponding applications of each tracker on an Android or iOS device simultaneously. Each participant was instructed to walk 200, 500, and 1,000 steps. Each set was repeated 40 times. Data was recorded after each trial, and the mean step count, standard deviation, accuracy, and precision were estimated for each tracker. Heart rate was measured by all trackers (if applicable), which support heart rate monitoring, and compared to a positive control, the Onyx Vantage 9590 professional clinical pulse oximeter. Results The accuracy of the tested products ranged between 79.8% and 99.1%, while the coefficient of variation (precision) ranged between 4% and 17.5%. MisFit Shine showed the highest accuracy and precision (along with Qualcomm Toq), while Samsung Gear 2 showed the lowest accuracy, and Jawbone UP showed the lowest precision. However, Xiaomi Mi band showed the best package compared to its price. Conclusions The accuracy and precision of the selected fitness trackers are reasonable and can indicate the average level of activity and thus average energy expenditure. PMID:26618039

  16. Are Currently Available Wearable Devices for Activity Tracking and Heart Rate Monitoring Accurate, Precise, and Medically Beneficial?

    PubMed

    El-Amrawy, Fatema; Nounou, Mohamed Ismail

    2015-10-01

    The new wave of wireless technologies, fitness trackers, and body sensor devices can have great impact on healthcare systems and the quality of life. However, there have not been enough studies to prove the accuracy and precision of these trackers. The objective of this study was to evaluate the accuracy, precision, and overall performance of seventeen wearable devices currently available compared with direct observation of step counts and heart rate monitoring. Each participant in this study used three accelerometers at a time, running the three corresponding applications of each tracker on an Android or iOS device simultaneously. Each participant was instructed to walk 200, 500, and 1,000 steps. Each set was repeated 40 times. Data was recorded after each trial, and the mean step count, standard deviation, accuracy, and precision were estimated for each tracker. Heart rate was measured by all trackers (if applicable), which support heart rate monitoring, and compared to a positive control, the Onyx Vantage 9590 professional clinical pulse oximeter. The accuracy of the tested products ranged between 79.8% and 99.1%, while the coefficient of variation (precision) ranged between 4% and 17.5%. MisFit Shine showed the highest accuracy and precision (along with Qualcomm Toq), while Samsung Gear 2 showed the lowest accuracy, and Jawbone UP showed the lowest precision. However, Xiaomi Mi band showed the best package compared to its price. The accuracy and precision of the selected fitness trackers are reasonable and can indicate the average level of activity and thus average energy expenditure.

  17. Precision Medicine: Functional Advancements.

    PubMed

    Caskey, Thomas

    2018-01-29

    Precision medicine was conceptualized on the strength of genomic sequence analysis. High-throughput functional metrics have enhanced sequence interpretation and clinical precision. These technologies include metabolomics, magnetic resonance imaging, and I rhythm (cardiac monitoring), among others. These technologies are discussed and placed in clinical context for the medical specialties of internal medicine, pediatrics, obstetrics, and gynecology. Publications in these fields support the concept of a higher level of precision in identifying disease risk. Precise disease risk identification has the potential to enable intervention with greater specificity, resulting in disease prevention-an important goal of precision medicine.

  18. Precision laser aiming system

    DOEpatents

    Ahrens, Brandon R [Albuquerque, NM; Todd, Steven N [Rio Rancho, NM

    2009-04-28

    A precision laser aiming system comprises a disrupter tool, a reflector, and a laser fixture. The disrupter tool, the reflector and the laser fixture are configurable for iterative alignment and aiming toward an explosive device threat. The invention enables a disrupter to be quickly and accurately set up, aligned, and aimed in order to render safe or to disrupt a target from a standoff position.

  19. Atomic Precision Plasma Processing - Modeling Investigations

    NASA Astrophysics Data System (ADS)

    Rauf, Shahid

    2016-09-01

    Sub-nanometer precision is increasingly being required of many critical plasma processes in the semiconductor industry. Some of these critical processes include atomic layer etch and plasma enhanced atomic layer deposition. Accurate control over ion energy and ion / radical composition is needed during plasma processing to meet the demanding atomic-precision requirements. While improvements in mainstream inductively and capacitively coupled plasmas can help achieve some of these goals, newer plasma technologies can expand the breadth of problems addressable by plasma processing. Computational modeling is used to examine issues relevant to atomic precision plasma processing in this paper. First, a molecular dynamics model is used to investigate atomic layer etch of Si and SiO2 in Cl2 and fluorocarbon plasmas. Both planar surfaces and nanoscale structures are considered. It is shown that accurate control of ion energy in the sub-50 eV range is necessary for atomic scale precision. In particular, if the ion energy is greater than 10 eV during plasma processing, several atomic layers get damaged near the surface. Low electron temperature (Te) plasmas are particularly attractive for atomic precision plasma processing due to their low plasma potential. One of the most attractive options in this regard is energetic-electron beam generated plasma, where Te <0.5 eV has been achieved in plasmas of molecular gases. These low Te plasmas are computationally examined in this paper using a hybrid fluid-kinetic model. It is shown that such plasmas not only allow for sub-5 eV ion energies, but also enable wider range of ion / radical composition. Coauthors: Jun-Chieh Wang, Jason Kenney, Ankur Agarwal, Leonid Dorf, and Ken Collins.

  20. Ultra-accurate collaborative information filtering via directed user similarity

    NASA Astrophysics Data System (ADS)

    Guo, Q.; Song, W.-J.; Liu, J.-G.

    2014-07-01

    A key challenge of the collaborative filtering (CF) information filtering is how to obtain the reliable and accurate results with the help of peers' recommendation. Since the similarities from small-degree users to large-degree users would be larger than the ones in opposite direction, the large-degree users' selections are recommended extensively by the traditional second-order CF algorithms. By considering the users' similarity direction and the second-order correlations to depress the influence of mainstream preferences, we present the directed second-order CF (HDCF) algorithm specifically to address the challenge of accuracy and diversity of the CF algorithm. The numerical results for two benchmark data sets, MovieLens and Netflix, show that the accuracy of the new algorithm outperforms the state-of-the-art CF algorithms. Comparing with the CF algorithm based on random walks proposed by Liu et al. (Int. J. Mod. Phys. C, 20 (2009) 285) the average ranking score could reach 0.0767 and 0.0402, which is enhanced by 27.3% and 19.1% for MovieLens and Netflix, respectively. In addition, the diversity, precision and recall are also enhanced greatly. Without relying on any context-specific information, tuning the similarity direction of CF algorithms could obtain accurate and diverse recommendations. This work suggests that the user similarity direction is an important factor to improve the personalized recommendation performance.

  1. Application of Smart Infrastructure Systems approach to precision medicine.

    PubMed

    Govindaraju, Diddahally R; Annaswamy, Anuradha M

    2015-12-01

    All biological variation is hierarchically organized dynamic network system of genomic components, organelles, cells, tissues, organs, individuals, families, populations and metapopulations. Individuals are axial in this hierarchy, as they represent antecedent, attendant and anticipated aspects of health, disease, evolution and medical care. Humans show individual specific genetic and clinical features such as complexity, cooperation, resilience, robustness, vulnerability, self-organization, latent and emergent behavior during their development, growth and senescence. Accurate collection, measurement, organization and analyses of individual specific data, embedded at all stratified levels of biological, demographic and cultural diversity - the big data - is necessary to make informed decisions on health, disease and longevity; which is a central theme of precision medicine initiative (PMI). This initiative also calls for the development of novel analytical approaches to handle complex multidimensional data. Here we suggest the application of Smart Infrastructure Systems (SIS) approach to accomplish some of the goals set forth by the PMI on the premise that biological systems and the SIS share many common features. The latter has been successfully employed in managing complex networks of non-linear adaptive controls, commonly encountered in smart engineering systems. We highlight their concordance and discuss the utility of the SIS approach in precision medicine programs.

  2. Patient-specific distal radius locking plate for fixation and accurate 3D positioning in corrective osteotomy.

    PubMed

    Dobbe, J G G; Vroemen, J C; Strackee, S D; Streekstra, G J

    2014-11-01

    Preoperative three-dimensional planning methods have been described extensively. However, transferring the virtual plan to the patient is often challenging. In this report, we describe the management of a severely malunited distal radius fracture using a patient-specific plate for accurate spatial positioning and fixation. Twenty months postoperatively the patient shows almost painless reconstruction and a nearly normal range of motion.

  3. High precision, rapid laser hole drilling

    DOEpatents

    Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.

    2007-03-20

    A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.

  4. High precision, rapid laser hole drilling

    DOEpatents

    Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.

    2005-03-08

    A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.

  5. High precision, rapid laser hole drilling

    DOEpatents

    Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.

    2013-04-02

    A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.

  6. Locally induced neuronal synchrony precisely propagates to specific cortical areas without rhythm distortion.

    PubMed

    Toda, Haruo; Kawasaki, Keisuke; Sato, Sho; Horie, Masao; Nakahara, Kiyoshi; Bepari, Asim K; Sawahata, Hirohito; Suzuki, Takafumi; Okado, Haruo; Takebayashi, Hirohide; Hasegawa, Isao

    2018-05-16

    Propagation of oscillatory spike firing activity at specific frequencies plays an important role in distributed cortical networks. However, there is limited evidence for how such frequency-specific signals are induced or how the signal spectra of the propagating signals are modulated during across-layer (radial) and inter-areal (tangential) neuronal interactions. To directly evaluate the direction specificity of spectral changes in a spiking cortical network, we selectively photostimulated infragranular excitatory neurons in the rat primary visual cortex (V1) at a supra-threshold level with various frequencies, and recorded local field potentials (LFPs) at the infragranular stimulation site, the cortical surface site immediately above the stimulation site in V1, and cortical surface sites outside V1. We found a significant reduction of LFP powers during radial propagation, especially at high-frequency stimulation conditions. Moreover, low-gamma-band dominant rhythms were transiently induced during radial propagation. Contrastingly, inter-areal LFP propagation, directed to specific cortical sites, accompanied no significant signal reduction nor gamma-band power induction. We propose an anisotropic mechanism for signal processing in the spiking cortical network, in which the neuronal rhythms are locally induced/modulated along the radial direction, and then propagate without distortion via intrinsic horizontal connections for spatiotemporally precise, inter-areal communication.

  7. The Qatar genome: a population-specific tool for precision medicine in the Middle East

    PubMed Central

    Fakhro, Khalid A; Staudt, Michelle R; Ramstetter, Monica Denise; Robay, Amal; Malek, Joel A; Badii, Ramin; Al-Marri, Ajayeb Al-Nabet; Khalil, Charbel Abi; Al-Shakaki, Alya; Chidiac, Omar; Stadler, Dora; Zirie, Mahmoud; Jayyousi, Amin; Salit, Jacqueline; Mezey, Jason G; Crystal, Ronald G; Rodriguez-Flores, Juan L

    2016-01-01

    Reaching the full potential of precision medicine depends on the quality of personalized genome interpretation. In order to facilitate precision medicine in regions of the Middle East and North Africa (MENA), a population-specific genome for the indigenous Arab population of Qatar (QTRG) was constructed by incorporating allele frequency data from sequencing of 1,161 Qataris, representing 0.4% of the population. A total of 20.9 million single nucleotide polymorphisms (SNPs) and 3.1 million indels were observed in Qatar, including an average of 1.79% novel variants per individual genome. Replacement of the GRCh37 standard reference with QTRG in a best practices genome analysis workflow resulted in an average of 7* deeper coverage depth (an improvement of 23%) and 756,671 fewer variants on average, a reduction of 16% that is attributed to common Qatari alleles being present in QTRG. The benefit for using QTRG varies across ancestries, a factor that should be taken into consideration when selecting an appropriate reference for analysis. PMID:27408750

  8. ChIP-seq Accurately Predicts Tissue-Specific Activity of Enhancers

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

    Visel, Axel; Blow, Matthew J.; Li, Zirong

    2009-02-01

    A major yet unresolved quest in decoding the human genome is the identification of the regulatory sequences that control the spatial and temporal expression of genes. Distant-acting transcriptional enhancers are particularly challenging to uncover since they are scattered amongst the vast non-coding portion of the genome. Evolutionary sequence constraint can facilitate the discovery of enhancers, but fails to predict when and where they are active in vivo. Here, we performed chromatin immunoprecipitation with the enhancer-associated protein p300, followed by massively-parallel sequencing, to map several thousand in vivo binding sites of p300 in mouse embryonic forebrain, midbrain, and limb tissue. Wemore » tested 86 of these sequences in a transgenic mouse assay, which in nearly all cases revealed reproducible enhancer activity in those tissues predicted by p300 binding. Our results indicate that in vivo mapping of p300 binding is a highly accurate means for identifying enhancers and their associated activities and suggest that such datasets will be useful to study the role of tissue-specific enhancers in human biology and disease on a genome-wide scale.« less

  9. Precision Medicine and Men's Health.

    PubMed

    Mata, Douglas A; Katchi, Farhan M; Ramasamy, Ranjith

    2017-07-01

    Precision medicine can greatly benefit men's health by helping to prevent, diagnose, and treat prostate cancer, benign prostatic hyperplasia, infertility, hypogonadism, and erectile dysfunction. For example, precision medicine can facilitate the selection of men at high risk for prostate cancer for targeted prostate-specific antigen screening and chemoprevention administration, as well as assist in identifying men who are resistant to medical therapy for prostatic hyperplasia, who may instead require surgery. Precision medicine-trained clinicians can also let couples know whether their specific cause of infertility should be bypassed by sperm extraction and in vitro fertilization to prevent abnormalities in their offspring. Though precision medicine's role in the management of hypogonadism has yet to be defined, it could be used to identify biomarkers associated with individual patients' responses to treatment so that appropriate therapy can be prescribed. Last, precision medicine can improve erectile dysfunction treatment by identifying genetic polymorphisms that regulate response to medical therapies and by aiding in the selection of patients for further cardiovascular disease screening.

  10. Precision aerial application for site-specific rice crop management

    USDA-ARS?s Scientific Manuscript database

    Precision agriculture includes different technologies that allow agricultural professional to use information management tools to optimize agriculture production. The new technologies allow aerial application applicators to improve application accuracy and efficiency, which saves time and money for...

  11. Large-scale extraction of accurate drug-disease treatment pairs from biomedical literature for drug repurposing

    PubMed Central

    2013-01-01

    Background A large-scale, highly accurate, machine-understandable drug-disease treatment relationship knowledge base is important for computational approaches to drug repurposing. The large body of published biomedical research articles and clinical case reports available on MEDLINE is a rich source of FDA-approved drug-disease indication as well as drug-repurposing knowledge that is crucial for applying FDA-approved drugs for new diseases. However, much of this information is buried in free text and not captured in any existing databases. The goal of this study is to extract a large number of accurate drug-disease treatment pairs from published literature. Results In this study, we developed a simple but highly accurate pattern-learning approach to extract treatment-specific drug-disease pairs from 20 million biomedical abstracts available on MEDLINE. We extracted a total of 34,305 unique drug-disease treatment pairs, the majority of which are not included in existing structured databases. Our algorithm achieved a precision of 0.904 and a recall of 0.131 in extracting all pairs, and a precision of 0.904 and a recall of 0.842 in extracting frequent pairs. In addition, we have shown that the extracted pairs strongly correlate with both drug target genes and therapeutic classes, therefore may have high potential in drug discovery. Conclusions We demonstrated that our simple pattern-learning relationship extraction algorithm is able to accurately extract many drug-disease pairs from the free text of biomedical literature that are not captured in structured databases. The large-scale, accurate, machine-understandable drug-disease treatment knowledge base that is resultant of our study, in combination with pairs from structured databases, will have high potential in computational drug repurposing tasks. PMID:23742147

  12. Temporally precise single-cell resolution optogenetics

    PubMed Central

    Shemesh, Or A.; Tanese, Dimitrii; Zampini, Valeria; Linghu, Changyang; Piatkevich, Kiryl; Ronzitti, Emiliano; Papagiakoumou, Eirini; Boyden, Edward S.; Emiliani, Valentina

    2017-01-01

    Optogenetic control of individual neurons with high temporal precision, within intact mammalian brain circuitry, would enable powerful explorations of how neural circuits operate. Two-photon computer generated holography enables precise sculpting of light, and could in principle enable simultaneous illumination of many neurons in a network, with the requisite temporal precision to simulate accurate neural codes. We designed a high efficacy soma-targeted opsin, finding that fusing the N-terminal 150 residues of kainate receptor subunit 2 (KA2) to the recently discovered high-photocurrent channelrhodopsin CoChR restricted expression of this opsin primarily to the cell body of mammalian cortical neurons. In combination with two-photon holographic stimulation, we found that this somatic CoChR (soCoChR) enabled photostimulation of individual cells in intact cortical circuits with single cell resolution and <1 millisecond temporal precision, and use soCoChR to perform connectivity mapping on intact cortical circuits. PMID:29184208

  13. High spatial precision nano-imaging of polarization-sensitive plasmonic particles

    NASA Astrophysics Data System (ADS)

    Liu, Yunbo; Wang, Yipei; Lee, Somin Eunice

    2018-02-01

    Precise polarimetric imaging of polarization-sensitive nanoparticles is essential for resolving their accurate spatial positions beyond the diffraction limit. However, conventional technologies currently suffer from beam deviation errors which cannot be corrected beyond the diffraction limit. To overcome this issue, we experimentally demonstrate a spatially stable nano-imaging system for polarization-sensitive nanoparticles. In this study, we show that by integrating a voltage-tunable imaging variable polarizer with optical microscopy, we are able to suppress beam deviation errors. We expect that this nano-imaging system should allow for acquisition of accurate positional and polarization information from individual nanoparticles in applications where real-time, high precision spatial information is required.

  14. Precision Oncology Medicine: The Clinical Relevance of Patient-Specific Biomarkers Used to Optimize Cancer Treatment.

    PubMed

    Schmidt, Keith T; Chau, Cindy H; Price, Douglas K; Figg, William D

    2016-12-01

    Precision medicine in oncology is the result of an increasing awareness of patient-specific clinical features coupled with the development of genomic-based diagnostics and targeted therapeutics. Companion diagnostics designed for specific drug-target pairs were the first to widely utilize clinically applicable tumor biomarkers (eg, HER2, EGFR), directing treatment for patients whose tumors exhibit a mutation susceptible to an FDA-approved targeted therapy (eg, trastuzumab, erlotinib). Clinically relevant germline mutations in drug-metabolizing enzymes and transporters (eg, TPMT, DPYD) have been shown to impact drug response, providing a rationale for individualized dosing to optimize treatment. The use of multigene expression-based assays to analyze an array of prognostic biomarkers has been shown to help direct treatment decisions, especially in breast cancer (eg, Oncotype DX). More recently, the use of next-generation sequencing to detect many potential "actionable" cancer molecular alterations is further shifting the 1 gene-1 drug paradigm toward a more comprehensive, multigene approach. Currently, many clinical trials (eg, NCI-MATCH, NCI-MPACT) are assessing novel diagnostic tools with a combination of different targeted therapeutics while also examining tumor biomarkers that were previously unexplored in a variety of cancer histologies. Results from ongoing trials such as the NCI-MATCH will help determine the clinical utility and future development of the precision-medicine approach. © 2016, The American College of Clinical Pharmacology.

  15. Performance Evaluation of Real-Time Precise Point Positioning Method

    NASA Astrophysics Data System (ADS)

    Alcay, Salih; Turgut, Muzeyyen

    2017-12-01

    Post-Processed Precise Point Positioning (PPP) is a well-known zero-difference positioning method which provides accurate and precise results. After the experimental tests, IGS Real Time Service (RTS) officially provided real time orbit and clock products for the GNSS community that allows real-time (RT) PPP applications. Different software packages can be used for RT-PPP. In this study, in order to evaluate the performance of RT-PPP, 3 IGS stations are used. Results, obtained by using BKG Ntrip Client (BNC) Software v2.12, are examined in terms of both accuracy and precision.

  16. Nanoscale tailor-made membranes for precise and rapid molecular sieve separation.

    PubMed

    Wang, Jing; Zhu, Junyong; Zhang, Yatao; Liu, Jindun; Van der Bruggen, Bart

    2017-03-02

    The precise and rapid separation of different molecules from aqueous, organic solutions and gas mixtures is critical to many technologies in the context of resource-saving and sustainable development. The strength of membrane-based technologies is well recognized and they are extensively applied as cost-effective, highly efficient separation techniques. Currently, empirical-based approaches, lacking an accurate nanoscale control, are used to prepare the most advanced membranes. In contrast, nanoscale control renders the membrane molecular specificity (sub-2 nm) necessary for efficient and rapid molecular separation. Therefore, as a growing trend in membrane technology, the field of nanoscale tailor-made membranes is highlighted in this review. An in-depth analysis of the latest advances in tailor-made membranes for precise and rapid molecule sieving is given, along with an outlook to future perspectives of such membranes. Special attention is paid to the established processing strategies, as well as the application of molecular dynamics (MD) simulation in nanoporous membrane design. This review will provide useful guidelines for future research in the development of nanoscale tailor-made membranes with a precise and rapid molecular sieve separation property.

  17. [Precision medicine: A major step forward in specific situations, a myth in refractory cancers?

    PubMed

    Albin, Nicolas; Mc Leer, Anne; Sakhri, Linda

    2018-04-01

    In recent years, high-throughput sequencing techniques have been developed for cancerology and many clinical trials are currently structured around biomarkers that can guide specific treatment choices. This approach is characteristic of precision medicine, which is actually a concept initiated several decades ago with, for example, retinoic acid in promyelocytic leukemia. This paper will review the different types of molecular alterations and « -omics » biological analyses, bioinformatics tools, coupled drug/biomarkers already validated, the ethical issues of whole genomic sequencing of an individual as part of an inclusion in a clinical trial and finally the first results of precision medicine trials. The AcSé crizotinib program, supported by the Inca (french Cancer National Institute), is emblematic of a success of this personalized medicine illustrated by 4 points: the discovery of a cohort of patients with lung cancer with a ROS1 rearrangement characteristic of a sensitivity to crizotinib, a rapid availability of this innovation through the implementation of a temporary recommendation for use (ANSM), the obtention of a conditional marketing authorization by the pharmaceutical industry and finally, financial assumption of responsibility by French social security (HAS), despite preliminary and non-comparative data. In the case of cancers refractory to standard chemotherapy, and regarding our system of access to drugs illustrated by the PROFILER clinical trial, this approach allows the access to a therapeutic drug targeting specific biomarkers only in 7% of patients included. This does not bode well for efficient treatment and even less for survival. Allowing patients to be included in trials that identify molecular targets by molecular screening, and not being able to propose the drug of interest is a traumatic event for those patients who live in the hope of an immediate future. In refractory disease we must rethink precision medicine in a more humanistic

  18. Research about the high precision temperature measurement

    NASA Astrophysics Data System (ADS)

    Lin, J.; Yu, J.; Zhu, X.; Zeng, Z.; Deng, Y.

    2012-12-01

    High precision temperature control system is one of most important support conditions for tunable birefringent filter.As the first step,we researched some high precision temperature measurement methods for it. Firstly, circuits with a 24 bit ADC as the sensor's reader were carefully designed; Secondly, an ARM porcessor is used as the centrol processing unit, it provides sufficient reading and procesing ability; Thirdly, three kinds of sensors, PT100, Dale 01T1002-5 thermistor, Wheatstone bridge(constructed by pure copper and manganin) as the senor of the temperature were tested respectively. The resolution of the measurement with these three kinds of sensors are all better than 0.001 that's enough for 0.01 stability temperature control. Comparatively, Dale 01T1002-5 thermistor could get the most accurate temperature of the key point, Wheatstone bridge could get the most accurate mean temperature of the whole layer, both of them will be used in our futrue temperature controll system.

  19. Recommendations for Accurate Resolution of Gene and Isoform Allele-Specific Expression in RNA-Seq Data

    PubMed Central

    Wood, David L. A.; Nones, Katia; Steptoe, Anita; Christ, Angelika; Harliwong, Ivon; Newell, Felicity; Bruxner, Timothy J. C.; Miller, David; Cloonan, Nicole; Grimmond, Sean M.

    2015-01-01

    Genetic variation modulates gene expression transcriptionally or post-transcriptionally, and can profoundly alter an individual’s phenotype. Measuring allelic differential expression at heterozygous loci within an individual, a phenomenon called allele-specific expression (ASE), can assist in identifying such factors. Massively parallel DNA and RNA sequencing and advances in bioinformatic methodologies provide an outstanding opportunity to measure ASE genome-wide. In this study, matched DNA and RNA sequencing, genotyping arrays and computationally phased haplotypes were integrated to comprehensively and conservatively quantify ASE in a single human brain and liver tissue sample. We describe a methodological evaluation and assessment of common bioinformatic steps for ASE quantification, and recommend a robust approach to accurately measure SNP, gene and isoform ASE through the use of personalized haplotype genome alignment, strict alignment quality control and intragenic SNP aggregation. Our results indicate that accurate ASE quantification requires careful bioinformatic analyses and is adversely affected by sample specific alignment confounders and random sampling even at moderate sequence depths. We identified multiple known and several novel ASE genes in liver, including WDR72, DSP and UBD, as well as genes that contained ASE SNPs with imbalance direction discordant with haplotype phase, explainable by annotated transcript structure, suggesting isoform derived ASE. The methods evaluated in this study will be of use to researchers performing highly conservative quantification of ASE, and the genes and isoforms identified as ASE of interest to researchers studying those loci. PMID:25965996

  20. Reliable low precision simulations in land surface models

    NASA Astrophysics Data System (ADS)

    Dawson, Andrew; Düben, Peter D.; MacLeod, David A.; Palmer, Tim N.

    2017-12-01

    Weather and climate models must continue to increase in both resolution and complexity in order that forecasts become more accurate and reliable. Moving to lower numerical precision may be an essential tool for coping with the demand for ever increasing model complexity in addition to increasing computing resources. However, there have been some concerns in the weather and climate modelling community over the suitability of lower precision for climate models, particularly for representing processes that change very slowly over long time-scales. These processes are difficult to represent using low precision due to time increments being systematically rounded to zero. Idealised simulations are used to demonstrate that a model of deep soil heat diffusion that fails when run in single precision can be modified to work correctly using low precision, by splitting up the model into a small higher precision part and a low precision part. This strategy retains the computational benefits of reduced precision whilst preserving accuracy. This same technique is also applied to a full complexity land surface model, resulting in rounding errors that are significantly smaller than initial condition and parameter uncertainties. Although lower precision will present some problems for the weather and climate modelling community, many of the problems can likely be overcome using a straightforward and physically motivated application of reduced precision.

  1. Novel serologic biomarkers provide accurate estimates of recent Plasmodium falciparum exposure for individuals and communities

    PubMed Central

    Helb, Danica A.; Tetteh, Kevin K. A.; Felgner, Philip L.; Skinner, Jeff; Hubbard, Alan; Arinaitwe, Emmanuel; Mayanja-Kizza, Harriet; Ssewanyana, Isaac; Kamya, Moses R.; Beeson, James G.; Tappero, Jordan; Smith, David L.; Crompton, Peter D.; Rosenthal, Philip J.; Dorsey, Grant; Drakeley, Christopher J.; Greenhouse, Bryan

    2015-01-01

    Tools to reliably measure Plasmodium falciparum (Pf) exposure in individuals and communities are needed to guide and evaluate malaria control interventions. Serologic assays can potentially produce precise exposure estimates at low cost; however, current approaches based on responses to a few characterized antigens are not designed to estimate exposure in individuals. Pf-specific antibody responses differ by antigen, suggesting that selection of antigens with defined kinetic profiles will improve estimates of Pf exposure. To identify novel serologic biomarkers of malaria exposure, we evaluated responses to 856 Pf antigens by protein microarray in 186 Ugandan children, for whom detailed Pf exposure data were available. Using data-adaptive statistical methods, we identified combinations of antibody responses that maximized information on an individual’s recent exposure. Responses to three novel Pf antigens accurately classified whether an individual had been infected within the last 30, 90, or 365 d (cross-validated area under the curve = 0.86–0.93), whereas responses to six antigens accurately estimated an individual’s malaria incidence in the prior year. Cross-validated incidence predictions for individuals in different communities provided accurate stratification of exposure between populations and suggest that precise estimates of community exposure can be obtained from sampling a small subset of that community. In addition, serologic incidence predictions from cross-sectional samples characterized heterogeneity within a community similarly to 1 y of continuous passive surveillance. Development of simple ELISA-based assays derived from the successful selection strategy outlined here offers the potential to generate rich epidemiologic surveillance data that will be widely accessible to malaria control programs. PMID:26216993

  2. Novel serologic biomarkers provide accurate estimates of recent Plasmodium falciparum exposure for individuals and communities.

    PubMed

    Helb, Danica A; Tetteh, Kevin K A; Felgner, Philip L; Skinner, Jeff; Hubbard, Alan; Arinaitwe, Emmanuel; Mayanja-Kizza, Harriet; Ssewanyana, Isaac; Kamya, Moses R; Beeson, James G; Tappero, Jordan; Smith, David L; Crompton, Peter D; Rosenthal, Philip J; Dorsey, Grant; Drakeley, Christopher J; Greenhouse, Bryan

    2015-08-11

    Tools to reliably measure Plasmodium falciparum (Pf) exposure in individuals and communities are needed to guide and evaluate malaria control interventions. Serologic assays can potentially produce precise exposure estimates at low cost; however, current approaches based on responses to a few characterized antigens are not designed to estimate exposure in individuals. Pf-specific antibody responses differ by antigen, suggesting that selection of antigens with defined kinetic profiles will improve estimates of Pf exposure. To identify novel serologic biomarkers of malaria exposure, we evaluated responses to 856 Pf antigens by protein microarray in 186 Ugandan children, for whom detailed Pf exposure data were available. Using data-adaptive statistical methods, we identified combinations of antibody responses that maximized information on an individual's recent exposure. Responses to three novel Pf antigens accurately classified whether an individual had been infected within the last 30, 90, or 365 d (cross-validated area under the curve = 0.86-0.93), whereas responses to six antigens accurately estimated an individual's malaria incidence in the prior year. Cross-validated incidence predictions for individuals in different communities provided accurate stratification of exposure between populations and suggest that precise estimates of community exposure can be obtained from sampling a small subset of that community. In addition, serologic incidence predictions from cross-sectional samples characterized heterogeneity within a community similarly to 1 y of continuous passive surveillance. Development of simple ELISA-based assays derived from the successful selection strategy outlined here offers the potential to generate rich epidemiologic surveillance data that will be widely accessible to malaria control programs.

  3. Precision Teaching, Frequency-Building, and Ballet Dancing

    ERIC Educational Resources Information Center

    Lokke, Gunn E. H.; Lokke, Jon A.; Arntzen, Erick

    2008-01-01

    This article reports the effectiveness of a brief intervention aimed at achieving fluency in basic ballet moves in a 9-year-old Norwegian girl by use of frequency-building and Precision Teaching procedures. One nonfluent ballet move was pinpointed, and instructional and training procedures designed to increase the frequency of accurate responding…

  4. Robotic Observatory System Design-Specification Considerations for Achieving Long-Term Sustainable Precision Performance

    NASA Astrophysics Data System (ADS)

    Wray, J. D.

    2003-05-01

    The robotic observatory telescope must point precisely on the target object, and then track autonomously to a fraction of the FWHM of the system PSF for durations of ten to twenty minutes or more. It must retain this precision while continuing to function at rates approaching thousands of observations per night for all its years of useful life. These stringent requirements raise new challenges unique to robotic telescope systems design. Critical design considerations are driven by the applicability of the above requirements to all systems of the robotic observatory, including telescope and instrument systems, telescope-dome enclosure systems, combined electrical and electronics systems, environmental (e.g. seeing) control systems and integrated computer control software systems. Traditional telescope design considerations include the effects of differential thermal strain, elastic flexure, plastic flexure and slack or backlash with respect to focal stability, optical alignment and angular pointing and tracking precision. Robotic observatory design must holistically encapsulate these traditional considerations within the overall objective of maximized long-term sustainable precision performance. This overall objective is accomplished through combining appropriate mechanical and dynamical system characteristics with a full-time real-time telescope mount model feedback computer control system. Important design considerations include: identifying and reducing quasi-zero-backlash; increasing size to increase precision; directly encoding axis shaft rotation; pointing and tracking operation via real-time feedback between precision mount model and axis mounted encoders; use of monolithic construction whenever appropriate for sustainable mechanical integrity; accelerating dome motion to eliminate repetitive shock; ducting internal telescope air to outside dome; and the principal design criteria: maximizing elastic repeatability while minimizing slack, plastic deformation

  5. How Advances in Imaging Will Affect Precision Radiation Oncology.

    PubMed

    Jaffray, David A; Das, Shiva; Jacobs, Paula M; Jeraj, Robert; Lambin, Philippe

    2018-06-01

    Radiation oncology is 1 of the most structured disciplines in medicine. It is of a highly technical nature with reliance on robotic systems to deliver intervention, engagement of diverse expertise, and early adoption of digital approaches to optimize and execute the application of this highly effective cancer treatment. As a localized intervention, the dependence on sensitive, specific, and accurate imaging to define the extent of disease, its heterogeneity, and adjacency to normal tissues directly affects the therapeutic ratio. Image-based in vivo temporal monitoring of the response to treatment enables adaptation and further affects the therapeutic ratio. Thus, more precise intervention will enable fractionation schedules that better interoperate with advances such as immunotherapy. In the data set-rich era that promises precision and personalized medicine, the radiation oncology field will integrate these new data into highly protocoled pathways of care that begin with multimodality prediction and enable patient-specific adaptation of therapy based on quantitative measures of the individual's dose-volume temporal trajectory and midtherapy predictions of response. In addition to advancements in computed tomography imaging, emerging technologies, such as ultra-high-field magnetic resonance and molecular imaging will bring new information to the design of treatments. Next-generation image guided radiation therapy systems will inject high specificity and sensitivity data and stimulate adaptive replanning. In addition, a myriad of pre- and peritherapeutic markers derived from advances in molecular pathology (eg, tumor genomics), automated and comprehensive imaging analytics (eg, radiomics, tumor microenvironment), and many other emerging biomarkers (eg, circulating tumor cell assays) will need to be integrated to maximize the benefit of radiation therapy for an individual patient. We present a perspective on the promise and challenges of fully exploiting imaging

  6. Precision medicine for nurses: 101.

    PubMed

    Lemoine, Colleen

    2014-05-01

    To introduce the key concepts and terms associated with precision medicine and support understanding of future developments in the field by providing an overview and history of precision medicine, related ethical considerations, and nursing implications. Current nursing, medical and basic science literature. Rapid progress in understanding the oncogenic drivers associated with cancer is leading to a shift toward precision medicine, where treatment is based on targeting specific genetic and epigenetic alterations associated with a particular cancer. Nurses will need to embrace the paradigm shift to precision medicine, expend the effort necessary to learn the essential terminology, concepts and principles, and work collaboratively with physician colleagues to best position our patients to maximize the potential that precision medicine can offer. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Platform Precision Autopilot Overview and Mission Performance

    NASA Technical Reports Server (NTRS)

    Strovers, Brian K.; Lee, James A.

    2009-01-01

    The Platform Precision Autopilot is an instrument landing system-interfaced autopilot system, developed to enable an aircraft to repeatedly fly nearly the same trajectory hours, days, or weeks later. The Platform Precision Autopilot uses a novel design to interface with a NASA Gulfstream III jet by imitating the output of an instrument landing system approach. This technique minimizes, as much as possible, modifications to the baseline Gulfstream III jet and retains the safety features of the aircraft autopilot. The Platform Precision Autopilot requirement is to fly within a 5-m (16.4-ft) radius tube for distances to 200 km (108 nmi) in the presence of light turbulence for at least 90 percent of the time. This capability allows precise repeat-pass interferometry for the Unmanned Aerial Vehicle Synthetic Aperture Radar program, whose primary objective is to develop a miniaturized, polarimetric, L-band synthetic aperture radar. Precise navigation is achieved using an accurate differential global positioning system developed by the Jet Propulsion Laboratory. Flight-testing has demonstrated the ability of the Platform Precision Autopilot to control the aircraft within the specified tolerance greater than 90 percent of the time in the presence of aircraft system noise and nonlinearities, constant pilot throttle adjustments, and light turbulence.

  8. NCI Precision Medicine

    Cancer.gov

    This illustration represents the National Cancer Institute’s support of research to improve precision medicine in cancer treatment, in which unique therapies treat an individual’s cancer based on specific genetic abnormalities of that person’s tumor.

  9. Linear signal noise summer accurately determines and controls S/N ratio

    NASA Technical Reports Server (NTRS)

    Sundry, J. L.

    1966-01-01

    Linear signal noise summer precisely controls the relative power levels of signal and noise, and mixes them linearly in accurately known ratios. The S/N ratio accuracy and stability are greatly improved by this technique and are attained simultaneously.

  10. High precision triangular waveform generator

    DOEpatents

    Mueller, Theodore R.

    1983-01-01

    An ultra-linear ramp generator having separately programmable ascending and descending ramp rates and voltages is provided. Two constant current sources provide the ramp through an integrator. Switching of the current at current source inputs rather than at the integrator input eliminates switching transients and contributes to the waveform precision. The triangular waveforms produced by the waveform generator are characterized by accurate reproduction and low drift over periods of several hours. The ascending and descending slopes are independently selectable.

  11. High-precision triangular-waveform generator

    DOEpatents

    Mueller, T.R.

    1981-11-14

    An ultra-linear ramp generator having separately programmable ascending and decending ramp rates and voltages is provided. Two constant current sources provide the ramp through an integrator. Switching of the current at current source inputs rather than at the integrator input eliminates switching transients and contributes to the waveform precision. The triangular waveforms produced by the waveform generator are characterized by accurate reproduction and low drift over periods of several hours. The ascending and descending slopes are independently selectable.

  12. Precise measurement of ultra-narrow laser linewidths using the strong coherent envelope

    NASA Astrophysics Data System (ADS)

    Huang, Shihong; Zhu, Tao; Liu, Min; Huang, Wei

    2017-02-01

    Laser linewidth narrowing down to kHz or even Hz is an important topic in areas like clock synchronization technology, laser radars, quantum optics, and high-precision detection. Conventional decoherence measurement methods like delayed self-heterodyne/homodyne interferometry cannot measure such narrow linewidths accurately. This is because a broadening of the Gaussian spectrum, which hides the laser’s intrinsic Lorentzian linewidth, cannot be avoided. Here, we introduce a new method using the strong coherent envelope to characterize the laser’s intrinsic linewidth through self-coherent detection. This method can eliminate the effect of the broadened Gaussian spectrum induced by the 1/f frequency noise. We analyze, in detail, the relationship between intrinsic laser linewidth, contrast difference with the second peak and the second trough (CDSPST) of the strong coherent envelope, and the length of the delaying fiber. The correct length for the delaying fiber can be chosen by combining the estimated laser linewidth (Δfest) with a specific CDSPST (ΔS) to obtain the accurate laser linewidth (Δf). Our results indicate that this method can be used as an accurate detection tool for measurements of narrow or super-narrow linewidths.

  13. Combined fabrication technique for high-precision aspheric optical windows

    NASA Astrophysics Data System (ADS)

    Hu, Hao; Song, Ci; Xie, Xuhui

    2016-07-01

    Specifications made on optical components are becoming more and more stringent with the performance improvement of modern optical systems. These strict requirements not only involve low spatial frequency surface accuracy, mid-and-high spatial frequency surface errors, but also surface smoothness and so on. This presentation mainly focuses on the fabrication process for square aspheric window which combines accurate grinding, magnetorheological finishing (MRF) and smoothing polishing (SP). In order to remove the low spatial frequency surface errors and subsurface defects after accurate grinding, the deterministic polishing method MRF with high convergence and stable material removal rate is applied. Then the SP technology with pseudo-random path is adopted to eliminate the mid-and-high spatial frequency surface ripples and high slope errors which is the defect for MRF. Additionally, the coordinate measurement method and interferometry are combined in different phase. Acid-etched method and ion beam figuring (IBF) are also investigated on observing and reducing the subsurface defects. Actual fabrication result indicates that the combined fabrication technique can lead to high machining efficiency on manufaturing the high-precision and high-quality optical aspheric windows.

  14. Bit Grooming: Statistically accurate precision-preserving quantization with compression, evaluated in the netCDF operators (NCO, v4.4.8+)

    DOE PAGES

    Zender, Charles S.

    2016-09-19

    Geoscientific models and measurements generate false precision (scientifically meaningless data bits) that wastes storage space. False precision can mislead (by implying noise is signal) and be scientifically pointless, especially for measurements. By contrast, lossy compression can be both economical (save space) and heuristic (clarify data limitations) without compromising the scientific integrity of data. Data quantization can thus be appropriate regardless of whether space limitations are a concern. We introduce, implement, and characterize a new lossy compression scheme suitable for IEEE floating-point data. Our new Bit Grooming algorithm alternately shaves (to zero) and sets (to one) the least significant bits ofmore » consecutive values to preserve a desired precision. This is a symmetric, two-sided variant of an algorithm sometimes called Bit Shaving that quantizes values solely by zeroing bits. Our variation eliminates the artificial low bias produced by always zeroing bits, and makes Bit Grooming more suitable for arrays and multi-dimensional fields whose mean statistics are important. Bit Grooming relies on standard lossless compression to achieve the actual reduction in storage space, so we tested Bit Grooming by applying the DEFLATE compression algorithm to bit-groomed and full-precision climate data stored in netCDF3, netCDF4, HDF4, and HDF5 formats. Bit Grooming reduces the storage space required by initially uncompressed and compressed climate data by 25–80 and 5–65 %, respectively, for single-precision values (the most common case for climate data) quantized to retain 1–5 decimal digits of precision. The potential reduction is greater for double-precision datasets. When used aggressively (i.e., preserving only 1–2 digits), Bit Grooming produces storage reductions comparable to other quantization techniques such as Linear Packing. Unlike Linear Packing, whose guaranteed precision rapidly degrades within the relatively narrow dynamic

  15. Bit Grooming: statistically accurate precision-preserving quantization with compression, evaluated in the netCDF Operators (NCO, v4.4.8+)

    NASA Astrophysics Data System (ADS)

    Zender, Charles S.

    2016-09-01

    Geoscientific models and measurements generate false precision (scientifically meaningless data bits) that wastes storage space. False precision can mislead (by implying noise is signal) and be scientifically pointless, especially for measurements. By contrast, lossy compression can be both economical (save space) and heuristic (clarify data limitations) without compromising the scientific integrity of data. Data quantization can thus be appropriate regardless of whether space limitations are a concern. We introduce, implement, and characterize a new lossy compression scheme suitable for IEEE floating-point data. Our new Bit Grooming algorithm alternately shaves (to zero) and sets (to one) the least significant bits of consecutive values to preserve a desired precision. This is a symmetric, two-sided variant of an algorithm sometimes called Bit Shaving that quantizes values solely by zeroing bits. Our variation eliminates the artificial low bias produced by always zeroing bits, and makes Bit Grooming more suitable for arrays and multi-dimensional fields whose mean statistics are important. Bit Grooming relies on standard lossless compression to achieve the actual reduction in storage space, so we tested Bit Grooming by applying the DEFLATE compression algorithm to bit-groomed and full-precision climate data stored in netCDF3, netCDF4, HDF4, and HDF5 formats. Bit Grooming reduces the storage space required by initially uncompressed and compressed climate data by 25-80 and 5-65 %, respectively, for single-precision values (the most common case for climate data) quantized to retain 1-5 decimal digits of precision. The potential reduction is greater for double-precision datasets. When used aggressively (i.e., preserving only 1-2 digits), Bit Grooming produces storage reductions comparable to other quantization techniques such as Linear Packing. Unlike Linear Packing, whose guaranteed precision rapidly degrades within the relatively narrow dynamic range of values that

  16. COSMOS: accurate detection of somatic structural variations through asymmetric comparison between tumor and normal samples

    PubMed Central

    Yamagata, Koichi; Yamanishi, Ayako; Kokubu, Chikara; Takeda, Junji; Sese, Jun

    2016-01-01

    An important challenge in cancer genomics is precise detection of structural variations (SVs) by high-throughput short-read sequencing, which is hampered by the high false discovery rates of existing analysis tools. Here, we propose an accurate SV detection method named COSMOS, which compares the statistics of the mapped read pairs in tumor samples with isogenic normal control samples in a distinct asymmetric manner. COSMOS also prioritizes the candidate SVs using strand-specific read-depth information. Performance tests on modeled tumor genomes revealed that COSMOS outperformed existing methods in terms of F-measure. We also applied COSMOS to an experimental mouse cell-based model, in which SVs were induced by genome engineering and gamma-ray irradiation, followed by polymerase chain reaction-based confirmation. The precision of COSMOS was 84.5%, while the next best existing method was 70.4%. Moreover, the sensitivity of COSMOS was the highest, indicating that COSMOS has great potential for cancer genome analysis. PMID:26833260

  17. Advancing Precision Nuclear Medicine and Molecular Imaging for Lymphoma.

    PubMed

    Wright, Chadwick L; Maly, Joseph J; Zhang, Jun; Knopp, Michael V

    2017-01-01

    PET with fluorodeoxyglucose F 18 ( 18 F FDG-PET) is a meaningful biomarker for the detection, targeted biopsy, and treatment of lymphoma. This article reviews the evolution of 18 F FDG-PET as a putative biomarker for lymphoma and addresses the current capabilities, challenges, and opportunities to enable precision medicine practices for lymphoma. Precision nuclear medicine is driven by new imaging technologies and methodologies to more accurately detect malignant disease. Although quantitative assessment of response is limited, such technologies will enable a more precise metabolic mapping with much higher definition image detail and thus may make it a robust and valid quantitative response assessment methodology. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Engineering the Mechanical Properties of Polymer Networks with Precise Doping of Primary Defects.

    PubMed

    Chan, Doreen; Ding, Yichuan; Dauskardt, Reinhold H; Appel, Eric A

    2017-12-06

    Polymer networks are extensively utilized across numerous applications ranging from commodity superabsorbent polymers and coatings to high-performance microelectronics and biomaterials. For many applications, desirable properties are known; however, achieving them has been challenging. Additionally, the accurate prediction of elastic modulus has been a long-standing difficulty owing to the presence of loops. By tuning the prepolymer formulation through precise doping of monomers, specific primary network defects can be programmed into an elastomeric scaffold, without alteration of their resulting chemistry. The addition of these monomers that respond mechanically as primary defects is used both to understand their impact on the resulting mechanical properties of the materials and as a method to engineer the mechanical properties. Indeed, these materials exhibit identical bulk and surface chemistry, yet vastly different mechanical properties. Further, we have adapted the real elastic network theory (RENT) to the case of primary defects in the absence of loops, thus providing new insights into the mechanism for material strength and failure in polymer networks arising from primary network defects, and to accurately predict the elastic modulus of the polymer system. The versatility of the approach we describe and the fundamental knowledge gained from this study can lead to new advancements in the development of novel materials with precisely defined and predictable chemical, physical, and mechanical properties.

  19. French Meteor Network for High Precision Orbits of Meteoroids

    NASA Technical Reports Server (NTRS)

    Atreya, P.; Vaubaillon, J.; Colas, F.; Bouley, S.; Gaillard, B.; Sauli, I.; Kwon, M. K.

    2011-01-01

    There is a lack of precise meteoroids orbit from video observations as most of the meteor stations use off-the-shelf CCD cameras. Few meteoroids orbit with precise semi-major axis are available using film photographic method. Precise orbits are necessary to compute the dust flux in the Earth s vicinity, and to estimate the ejection time of the meteoroids accurately by comparing them with the theoretical evolution model. We investigate the use of large CCD sensors to observe multi-station meteors and to compute precise orbit of these meteoroids. An ideal spatial and temporal resolution to get an accuracy to those similar of photographic plates are discussed. Various problems faced due to the use of large CCD, such as increasing the spatial and the temporal resolution at the same time and computational problems in finding the meteor position are illustrated.

  20. Value of Sample Return and High Precision Analyses: Need for A Resource of Compelling Stories, Metaphors and Examples for Public Speakers

    NASA Technical Reports Server (NTRS)

    Allton, J. H.

    2017-01-01

    There is widespread agreement among planetary scientists that much of what we know about the workings of the solar system comes from accurate, high precision measurements on returned samples. Precision is a function of the number of atoms the instrumentation is able to count. Accuracy depends on the calibration or standardization technique. For Genesis, the solar wind sample return mission, acquiring enough atoms to ensure precise SW measurements and then accurately quantifying those measurements were steps known to be non-trivial pre-flight. The difficulty of precise and accurate measurements on returned samples, and why they cannot be made remotely, is not communicated well to the public. In part, this is be-cause "high precision" is abstract and error bars are not very exciting topics. This paper explores ideas for collecting and compiling compelling metaphors and colorful examples as a resource for planetary science public speakers.

  1. The Precise Repositioning Instrument for Genioplasty and a Three-Dimensional Printing Technique for Treatment of Complex Facial Asymmetry.

    PubMed

    Wang, Lin; Tian, Dan; Sun, Xiumei; Xiao, Yanju; Chen, Li; Wu, Guomin

    2017-08-01

    Facial asymmetry is very common in maxillofacial deformities. It is difficult to achieve accurate reconstruction. With the help of 3D printing models and surgical templates, the osteotomy line and the amount of bone grinding can be accurate. Also, by means of the precise repositioning instrument, the repositioning of genioplasty can be accurate and quick. In this study, we present a three-dimensional printing technique and the precise repositioning instrument to guide the osteotomy and repositioning, and illustrate their feasibility and validity. Eight patients with complex facial asymmetries were studied. A precise 3D printing model was obtained. We made the preoperative design and surgical templates according to it. The surgical templates and precise repositioning instrument were used to obtain an accurate osteotomy and repositioning during the operation. Postoperative measurements were made based on computed tomographic data, including chin point deviation as well as the symmetry of the mandible evaluated by 3D curve functions. All patients obtained satisfactory esthetic results, and no recurrences occurred during follow-up. The results showed that we achieved clinically acceptable precision for the mandible and chin. The mean and SD of ICC between R-Post and L-Post were 0.973 ± 0.007. The mean and SD of chin point deviation 6 months after the operation were 0.63 ± 0.19 mm. The results of this study suggest that the three-dimensional printing technique and the precise repositioning instrument could aid in making better operation designs and more accurate manipulation in orthognathic surgery for complex facial asymmetry. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  2. Sex differences in accuracy and precision when judging time to arrival: data from two Internet studies.

    PubMed

    Sanders, Geoff; Sinclair, Kamila

    2011-12-01

    We report two Internet studies that investigated sex differences in the accuracy and precision of judging time to arrival. We used accuracy to mean the ability to match the actual time to arrival and precision to mean the consistency with which each participant made their judgments. Our task was presented as a computer game in which a toy UFO moved obliquely towards the participant through a virtual three-dimensional space on route to a docking station. The UFO disappeared before docking and participants pressed their space bar at the precise moment they thought the UFO would have docked. Study 1 showed it was possible to conduct quantitative studies of spatiotemporal judgments in virtual reality via the Internet and confirmed reports that men are more accurate because women underestimate, but found no difference in precision measured as intra-participant variation. Study 2 repeated Study 1 with five additional presentations of one condition to provide a better measure of precision. Again, men were more accurate than women but there were no sex differences in precision. However, within the coincidence-anticipation timing (CAT) literature, of those studies that report sex differences, a majority found that males are both more accurate and more precise than females. Noting that many CAT studies report no sex differences, we discuss appropriate interpretations of such null findings. While acknowledging that CAT performance may be influenced by experience we suggest that the sex difference may have originated among our ancestors with the evolutionary selection of men for hunting and women for gathering.

  3. Sex-specific lean body mass predictive equations are accurate in the obese paediatric population

    PubMed Central

    Jackson, Lanier B.; Henshaw, Melissa H.; Carter, Janet; Chowdhury, Shahryar M.

    2015-01-01

    Background The clinical assessment of lean body mass (LBM) is challenging in obese children. A sex-specific predictive equation for LBM derived from anthropometric data was recently validated in children. Aim The purpose of this study was to independently validate these predictive equations in the obese paediatric population. Subjects and methods Obese subjects aged 4–21 were analysed retrospectively. Predicted LBM (LBMp) was calculated using equations previously developed in children. Measured LBM (LBMm) was derived from dual-energy x-ray absorptiometry. Agreement was expressed as [(LBMm-LBMp)/LBMm] with 95% limits of agreement. Results Of 310 enrolled patients, 195 (63%) were females. The mean age was 11.8 ± 3.4 years and mean BMI Z-score was 2.3 ± 0.4. The average difference between LBMm and LBMp was −0.6% (−17.0%, 15.8%). Pearson’s correlation revealed a strong linear relationship between LBMm and LBMp (r=0.97, p<0.01). Conclusion This study validates the use of these clinically-derived sex-specific LBM predictive equations in the obese paediatric population. Future studies should use these equations to improve the ability to accurately classify LBM in obese children. PMID:26287383

  4. Precision and repeatability of the Optotrak 3020 motion measurement system.

    PubMed

    States, R A; Pappas, E

    2006-01-01

    Several motion analysis systems are used by researchers to quantify human motion and to perform accurate surgical procedures. The Optotrak 3020 is one of these systems and despite its widespread use there is not any published information on its precision and repeatability. We used a repeated measures design study to evaluate the precision and repeatability of the Optotrak 3020 by measuring distance and angle in three sessions, four distances and three conditions (motion, static vertical, and static tilted). Precision and repeatability were found to be excellent for both angle and distance although they decreased with increasing distance from the sensors and with tilt from the plane of the sensors. Motion did not have a significant effect on the precision of the measurements. In conclusion, the measurement error of the Optotrak is minimal. Further studies are needed to evaluate its precision and repeatability under human motion conditions.

  5. An accurate registration technique for distorted images

    NASA Technical Reports Server (NTRS)

    Delapena, Michele; Shaw, Richard A.; Linde, Peter; Dravins, Dainis

    1990-01-01

    Accurate registration of International Ultraviolet Explorer (IUE) images is crucial because the variability of the geometrical distortions that are introduced by the SEC-Vidicon cameras ensures that raw science images are never perfectly aligned with the Intensity Transfer Functions (ITFs) (i.e., graded floodlamp exposures that are used to linearize and normalize the camera response). A technique for precisely registering IUE images which uses a cross correlation of the fixed pattern that exists in all raw IUE images is described.

  6. Platform Precision Autopilot Overview and Flight Test Results

    NASA Technical Reports Server (NTRS)

    Lin, V.; Strovers, B.; Lee, J.; Beck, R.

    2008-01-01

    The Platform Precision Autopilot is an instrument landing system interfaced autopilot system, developed to enable an aircraft to repeatedly fly nearly the same trajectory hours, days, or weeks later. The Platform Precision Autopilot uses a novel design to interface with a NASA Gulfstream III jet by imitating the output of an instrument landing system approach. This technique minimizes, as much as possible, modifications to the baseline Gulfstream III jet and retains the safety features of the aircraft autopilot. The Platform Precision Autopilot requirement is to fly within a 5-m (16.4-ft) radius tube for distances to 200 km (108 nmi) in the presence of light turbulence for at least 90 percent of the time. This capability allows precise repeat-pass interferometry for the Uninhabited Aerial Vehicle Synthetic Aperture Radar program, whose primary objective is to develop a miniaturized, polarimetric, L-band synthetic aperture radar. Precise navigation is achieved using an accurate differential global positioning system developed by the Jet Propulsion Laboratory. Flight-testing has demonstrated the ability of the Platform Precision Autopilot to control the aircraft within the specified tolerance greater than 90 percent of the time in the presence of aircraft system noise and nonlinearities, constant pilot throttle adjustments, and light turbulence.

  7. The precise and accurate production of millimetric water droplets using a superhydrophobic generating apparatus

    NASA Astrophysics Data System (ADS)

    Wood, Michael J.; Aristizabal, Felipe; Coady, Matthew; Nielson, Kent; Ragogna, Paul J.; Kietzig, Anne-Marie

    2018-02-01

    The production of millimetric liquid droplets has importance in a wide range of applications both in the laboratory and industrially. As such, much effort has been put forth to devise methods to generate these droplets on command in a manner which results in high diameter accuracy and precision, well-defined trajectories followed by successive droplets and low oscillations in droplet shape throughout their descents. None of the currently employed methods of millimetric droplet generation described in the literature adequately addresses all of these desired droplet characteristics. The reported methods invariably involve the cohesive separation of the desired volume of liquid from the bulk supply in the same step that separates the single droplet from the solid generator. We have devised a droplet generation device which separates the desired volume of liquid within a tee-apparatus in a step prior to the generation of the droplet which has yielded both high accuracy and precision of the diameters of the final droplets produced. Further, we have engineered a generating tip with extreme antiwetting properties which has resulted in reduced adhesion forces between the liquid droplet and the solid tip. This has yielded the ability to produce droplets of low mass without necessitating different diameter generating tips or the addition of surfactants to the liquid, well-defined droplet trajectories, and low oscillations in droplet volume. The trajectories and oscillations of the droplets produced have been assessed and presented quantitatively in a manner that has been lacking in the current literature.

  8. Precision Pointing Control to and Accurate Target Estimation of a Non-Cooperative Vehicle

    NASA Technical Reports Server (NTRS)

    VanEepoel, John; Thienel, Julie; Sanner, Robert M.

    2006-01-01

    In 2004, NASA began investigating a robotic servicing mission for the Hubble Space Telescope (HST). Such a mission would not only require estimates of the HST attitude and rates in order to achieve capture by the proposed Hubble Robotic Vehicle (HRV), but also precision control to achieve the desired rate and maintain the orientation to successfully dock with HST. To generalize the situation, HST is the target vehicle and HRV is the chaser. This work presents a nonlinear approach for estimating the body rates of a non-cooperative target vehicle, and coupling this estimation to a control scheme. Non-cooperative in this context relates to the target vehicle no longer having the ability to maintain attitude control or transmit attitude knowledge.

  9. Accuracy, precision, usability, and cost of portable silver test methods for ceramic filter factories.

    PubMed

    Meade, Rhiana D; Murray, Anna L; Mittelman, Anjuliee M; Rayner, Justine; Lantagne, Daniele S

    2017-02-01

    Locally manufactured ceramic water filters are one effective household drinking water treatment technology. During manufacturing, silver nanoparticles or silver nitrate are applied to prevent microbiological growth within the filter and increase bacterial removal efficacy. Currently, there is no recommendation for manufacturers to test silver concentrations of application solutions or filtered water. We identified six commercially available silver test strips, kits, and meters, and evaluated them by: (1) measuring in quintuplicate six samples from 100 to 1,000 mg/L (application range) and six samples from 0.0 to 1.0 mg/L (effluent range) of silver nanoparticles and silver nitrate to determine accuracy and precision; (2) conducting volunteer testing to assess ease-of-use; and (3) comparing costs. We found no method accurately detected silver nanoparticles, and accuracy ranged from 4 to 91% measurement error for silver nitrate samples. Most methods were precise, but only one method could test both application and effluent concentration ranges of silver nitrate. Volunteers considered test strip methods easiest. The cost for 100 tests ranged from 36 to 1,600 USD. We found no currently available method accurately and precisely measured both silver types at reasonable cost and ease-of-use, thus these methods are not recommended to manufacturers. We recommend development of field-appropriate methods that accurately and precisely measure silver nanoparticle and silver nitrate concentrations.

  10. High-Precision Registration of Point Clouds Based on Sphere Feature Constraints.

    PubMed

    Huang, Junhui; Wang, Zhao; Gao, Jianmin; Huang, Youping; Towers, David Peter

    2016-12-30

    Point cloud registration is a key process in multi-view 3D measurements. Its precision affects the measurement precision directly. However, in the case of the point clouds with non-overlapping areas or curvature invariant surface, it is difficult to achieve a high precision. A high precision registration method based on sphere feature constraint is presented to overcome the difficulty in the paper. Some known sphere features with constraints are used to construct virtual overlapping areas. The virtual overlapping areas provide more accurate corresponding point pairs and reduce the influence of noise. Then the transformation parameters between the registered point clouds are solved by an optimization method with weight function. In that case, the impact of large noise in point clouds can be reduced and a high precision registration is achieved. Simulation and experiments validate the proposed method.

  11. High-Precision Registration of Point Clouds Based on Sphere Feature Constraints

    PubMed Central

    Huang, Junhui; Wang, Zhao; Gao, Jianmin; Huang, Youping; Towers, David Peter

    2016-01-01

    Point cloud registration is a key process in multi-view 3D measurements. Its precision affects the measurement precision directly. However, in the case of the point clouds with non-overlapping areas or curvature invariant surface, it is difficult to achieve a high precision. A high precision registration method based on sphere feature constraint is presented to overcome the difficulty in the paper. Some known sphere features with constraints are used to construct virtual overlapping areas. The virtual overlapping areas provide more accurate corresponding point pairs and reduce the influence of noise. Then the transformation parameters between the registered point clouds are solved by an optimization method with weight function. In that case, the impact of large noise in point clouds can be reduced and a high precision registration is achieved. Simulation and experiments validate the proposed method. PMID:28042846

  12. Bit-Grooming: Shave Your Bits with Razor-sharp Precision

    NASA Astrophysics Data System (ADS)

    Zender, C. S.; Silver, J.

    2017-12-01

    Lossless compression can reduce climate data storage by 30-40%. Further reduction requires lossy compression that also reduces precision. Fortunately, geoscientific models and measurements generate false precision (scientifically meaningless data bits) that can be eliminated without sacrificing scientifically meaningful data. We introduce Bit Grooming, a lossy compression algorithm that removes the bloat due to false-precision, those bits and bytes beyond the meaningful precision of the data.Bit Grooming is statistically unbiased, applies to all floating point numbers, and is easy to use. Bit-Grooming reduces geoscience data storage requirements by 40-80%. We compared Bit Grooming to competitors Linear Packing, Layer Packing, and GRIB2/JPEG2000. The other compression methods have the edge in terms of compression, but Bit Grooming is the most accurate and certainly the most usable and portable.Bit Grooming provides flexible and well-balanced solutions to the trade-offs among compression, accuracy, and usability required by lossy compression. Geoscientists could reduce their long term storage costs, and show leadership in the elimination of false precision, by adopting Bit Grooming.

  13. Precision Agriculture. Reaping the Benefits of Technological Growth. Resources in Technology.

    ERIC Educational Resources Information Center

    Hadley, Joel F.

    1998-01-01

    Technological innovations have revolutionized farming. Using precision farming techniques, farmers get an accurate picture of a field's attributes, such as soil properties, yield rates, and crop characteristics through the use of Differential Global Positioning Satellite hardware. (JOW)

  14. Precision Education Initiative: Moving toward Personalized Education

    ERIC Educational Resources Information Center

    Hart, Sara A.

    2016-01-01

    This article proposes the Precision Education Initiative, which is the tailoring of education to the specific characteristics of the individual student. Mirroring precision medicine, the author lays out both near-term and longer term goals that educational research, and importantly educational practice, should follow.

  15. Obtaining accurate amounts of mercury from mercury compounds via electrolytic methods

    DOEpatents

    Grossman, Mark W.; George, William A.

    1987-01-01

    A process for obtaining pre-determined, accurate rate amounts of mercury. In one embodiment, predetermined, precise amounts of Hg are separated from HgO and plated onto a cathode wire. The method for doing this involves dissolving a precise amount of HgO which corresponds to a pre-determined amount of Hg desired in an electrolyte solution comprised of glacial acetic acid and H.sub.2 O. The mercuric ions are then electrolytically reduced and plated onto a cathode producing the required pre-determined quantity of Hg. In another embodiment, pre-determined, precise amounts of Hg are obtained from Hg.sub.2 Cl.sub.2. The method for doing this involves dissolving a precise amount of Hg.sub.2 Cl.sub.2 in an electrolyte solution comprised of concentrated HCl and H.sub.2 O. The mercurous ions in solution are then electrolytically reduced and plated onto a cathode wire producing the required, pre-determined quantity of Hg.

  16. Obtaining accurate amounts of mercury from mercury compounds via electrolytic methods

    DOEpatents

    Grossman, M.W.; George, W.A.

    1987-07-07

    A process is described for obtaining pre-determined, accurate rate amounts of mercury. In one embodiment, predetermined, precise amounts of Hg are separated from HgO and plated onto a cathode wire. The method for doing this involves dissolving a precise amount of HgO which corresponds to a pre-determined amount of Hg desired in an electrolyte solution comprised of glacial acetic acid and H[sub 2]O. The mercuric ions are then electrolytically reduced and plated onto a cathode producing the required pre-determined quantity of Hg. In another embodiment, pre-determined, precise amounts of Hg are obtained from Hg[sub 2]Cl[sub 2]. The method for doing this involves dissolving a precise amount of Hg[sub 2]Cl[sub 2] in an electrolyte solution comprised of concentrated HCl and H[sub 2]O. The mercurous ions in solution are then electrolytically reduced and plated onto a cathode wire producing the required, pre-determined quantity of Hg. 1 fig.

  17. Portable high precision pressure transducer system

    DOEpatents

    Piper, Thomas C.; Morgan, John P.; Marchant, Norman J.; Bolton, Steven M.

    1994-01-01

    A high precision pressure transducer system for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank. Since the response of the pressure transducer is temperature sensitive, it is continually housed in an battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum florescent display.

  18. Portable high precision pressure transducer system

    DOEpatents

    Piper, T.C.; Morgan, J.P.; Marchant, N.J.; Bolton, S.M.

    1994-04-26

    A high precision pressure transducer system is described for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank. Since the response of the pressure transducer is temperature sensitive, it is continually housed in an battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum fluorescent display. 2 figures.

  19. Automated Gravimetric Calibration to Optimize the Accuracy and Precision of TECAN Freedom EVO Liquid Handler

    PubMed Central

    Bessemans, Laurent; Jully, Vanessa; de Raikem, Caroline; Albanese, Mathieu; Moniotte, Nicolas; Silversmet, Pascal; Lemoine, Dominique

    2016-01-01

    High-throughput screening technologies are increasingly integrated into the formulation development process of biopharmaceuticals. The performance of liquid handling systems is dependent on the ability to deliver accurate and precise volumes of specific reagents to ensure process quality. We have developed an automated gravimetric calibration procedure to adjust the accuracy and evaluate the precision of the TECAN Freedom EVO liquid handling system. Volumes from 3 to 900 µL using calibrated syringes and fixed tips were evaluated with various solutions, including aluminum hydroxide and phosphate adjuvants, β-casein, sucrose, sodium chloride, and phosphate-buffered saline. The methodology to set up liquid class pipetting parameters for each solution was to split the process in three steps: (1) screening of predefined liquid class, including different pipetting parameters; (2) adjustment of accuracy parameters based on a calibration curve; and (3) confirmation of the adjustment. The run of appropriate pipetting scripts, data acquisition, and reports until the creation of a new liquid class in EVOware was fully automated. The calibration and confirmation of the robotic system was simple, efficient, and precise and could accelerate data acquisition for a wide range of biopharmaceutical applications. PMID:26905719

  20. Precise montaging and metric quantification of retinal surface area from ultra-widefield fundus photography and fluorescein angiography.

    PubMed

    Croft, Daniel E; van Hemert, Jano; Wykoff, Charles C; Clifton, David; Verhoek, Michael; Fleming, Alan; Brown, David M

    2014-01-01

    Accurate quantification of retinal surface area from ultra-widefield (UWF) images is challenging due to warping produced when the retina is projected onto a two-dimensional plane for analysis. By accounting for this, the authors sought to precisely montage and accurately quantify retinal surface area in square millimeters. Montages were created using Optos 200Tx (Optos, Dunfermline, U.K.) images taken at different gaze angles. A transformation projected the images to their correct location on a three-dimensional model. Area was quantified with spherical trigonometry. Warping, precision, and accuracy were assessed. Uncorrected, posterior pixels represented up to 79% greater surface area than peripheral pixels. Assessing precision, a standard region was quantified across 10 montages of the same eye (RSD: 0.7%; mean: 408.97 mm(2); range: 405.34-413.87 mm(2)). Assessing accuracy, 50 patients' disc areas were quantified (mean: 2.21 mm(2); SE: 0.06 mm(2)), and the results fell within the normative range. By accounting for warping inherent in UWF images, precise montaging and accurate quantification of retinal surface area in square millimeters were achieved. Copyright 2014, SLACK Incorporated.

  1. COSMOS: accurate detection of somatic structural variations through asymmetric comparison between tumor and normal samples.

    PubMed

    Yamagata, Koichi; Yamanishi, Ayako; Kokubu, Chikara; Takeda, Junji; Sese, Jun

    2016-05-05

    An important challenge in cancer genomics is precise detection of structural variations (SVs) by high-throughput short-read sequencing, which is hampered by the high false discovery rates of existing analysis tools. Here, we propose an accurate SV detection method named COSMOS, which compares the statistics of the mapped read pairs in tumor samples with isogenic normal control samples in a distinct asymmetric manner. COSMOS also prioritizes the candidate SVs using strand-specific read-depth information. Performance tests on modeled tumor genomes revealed that COSMOS outperformed existing methods in terms of F-measure. We also applied COSMOS to an experimental mouse cell-based model, in which SVs were induced by genome engineering and gamma-ray irradiation, followed by polymerase chain reaction-based confirmation. The precision of COSMOS was 84.5%, while the next best existing method was 70.4%. Moreover, the sensitivity of COSMOS was the highest, indicating that COSMOS has great potential for cancer genome analysis. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  2. Precisely Tailored DNA Nanostructures and their Theranostic Applications.

    PubMed

    Zhu, Bing; Wang, Lihua; Li, Jiang; Fan, Chunhai

    2017-12-01

    A critical challenge in nanotechnology is the limited precision and controllability of the structural parameters, which brings about concerns in uniformity, reproducibility and performance. Self-assembled DNA nanostructures, as a newly emerged type of nano-biomaterials, possess low-nanometer precision, excellent programmability and addressability. They can precisely arrange various molecules and materials to form spatially ordered complex, resulting in unambiguous physical or chemical properties. Because of these, DNA nanostructures have shown great promise in numerous biomedical theranostic applications. In this account, we briefly review the history and advances on construction of DNA nanoarchitectures and superstructures with accurate structural parameters. We focus on recent progress in exploiting these DNA nanostructures as platforms for quantitative biosensing, intracellular diagnosis, imaging, and smart drug delivery. We also discuss key challenges in practical applications. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Toward precision medicine in Alzheimer's disease.

    PubMed

    Reitz, Christiane

    2016-03-01

    In Western societies, Alzheimer's disease (AD) is the most common form of dementia and the sixth leading cause of death. In recent years, the concept of precision medicine, an approach for disease prevention and treatment that is personalized to an individual's specific pattern of genetic variability, environment and lifestyle factors, has emerged. While for some diseases, in particular select cancers and a few monogenetic disorders such as cystic fibrosis, significant advances in precision medicine have been made over the past years, for most other diseases precision medicine is only in its beginning. To advance the application of precision medicine to a wider spectrum of disorders, governments around the world are starting to launch Precision Medicine Initiatives, major efforts to generate the extensive scientific knowledge needed to integrate the model of precision medicine into every day clinical practice. In this article we summarize the state of precision medicine in AD, review major obstacles in its development, and discuss its benefits in this highly prevalent, clinically and pathologically complex disease.

  4. 27 CFR 30.23 - Use of precision hydrometers and thermometers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... hydrometers and thermometers. 30.23 Section 30.23 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO... Use of precision hydrometers and thermometers. Care should be exercised to obtain accurate hydrometer... entire quantity. The hydrometers should be kept clean and free of any oily substance. Immediately before...

  5. Field precision machining technology of target chamber in ICF lasers

    NASA Astrophysics Data System (ADS)

    Xu, Yuanli; Wu, Wenkai; Shi, Sucun; Duan, Lin; Chen, Gang; Wang, Baoxu; Song, Yugang; Liu, Huilin; Zhu, Mingzhi

    2016-10-01

    In ICF lasers, many independent laser beams are required to be positioned on target with a very high degree of accuracy during a shot. The target chamber provides a precision platform and datum reference for final optics assembly and target collimation and location system. The target chamber consists of shell with welded flanges, reinforced concrete pedestal, and lateral support structure. The field precision machining technology of target chamber in ICF lasers have been developed based on ShenGuangIII (SGIII). The same center of the target chamber is adopted in the process of design, fabrication, and alignment. The technologies of beam collimation and datum reference transformation are developed for the fabrication, positioning and adjustment of target chamber. A supporting and rotating mechanism and a special drilling machine are developed to bore the holes of ports. An adjustment mechanism is designed to accurately position the target chamber. In order to ensure the collimation requirements of the beam leading and focusing and the target positioning, custom-machined spacers are used to accurately correct the alignment error of the ports. Finally, this paper describes the chamber center, orientation, and centering alignment error measurements of SGIII. The measurements show the field precision machining of SGIII target chamber meet its design requirement. These information can be used on similar systems.

  6. Accurate reconstruction of viral quasispecies spectra through improved estimation of strain richness

    PubMed Central

    2015-01-01

    Background Estimating the number of different species (richness) in a mixed microbial population has been a main focus in metagenomic research. Existing methods of species richness estimation ride on the assumption that the reads in each assembled contig correspond to only one of the microbial genomes in the population. This assumption and the underlying probabilistic formulations of existing methods are not useful for quasispecies populations where the strains are highly genetically related. The lack of knowledge on the number of different strains in a quasispecies population is observed to hinder the precision of existing Viral Quasispecies Spectrum Reconstruction (QSR) methods due to the uncontrolled reconstruction of a large number of in silico false positives. In this work, we formulated a novel probabilistic method for strain richness estimation specifically targeting viral quasispecies. By using this approach we improved our recently proposed spectrum reconstruction pipeline ViQuaS to achieve higher levels of precision in reconstructed quasispecies spectra without compromising the recall rates. We also discuss how one other existing popular QSR method named ShoRAH can be improved using this new approach. Results On benchmark data sets, our estimation method provided accurate richness estimates (< 0.2 median estimation error) and improved the precision of ViQuaS by 2%-13% and F-score by 1%-9% without compromising the recall rates. We also demonstrate that our estimation method can be used to improve the precision and F-score of ShoRAH by 0%-7% and 0%-5% respectively. Conclusions The proposed probabilistic estimation method can be used to estimate the richness of viral populations with a quasispecies behavior and to improve the accuracy of the quasispecies spectra reconstructed by the existing methods ViQuaS and ShoRAH in the presence of a moderate level of technical sequencing errors. Availability http://sourceforge.net/projects/viquas/ PMID:26678073

  7. The high cost of accurate knowledge.

    PubMed

    Sutcliffe, Kathleen M; Weber, Klaus

    2003-05-01

    Many business thinkers believe it's the role of senior managers to scan the external environment to monitor contingencies and constraints, and to use that precise knowledge to modify the company's strategy and design. As these thinkers see it, managers need accurate and abundant information to carry out that role. According to that logic, it makes sense to invest heavily in systems for collecting and organizing competitive information. Another school of pundits contends that, since today's complex information often isn't precise anyway, it's not worth going overboard with such investments. In other words, it's not the accuracy and abundance of information that should matter most to top executives--rather, it's how that information is interpreted. After all, the role of senior managers isn't just to make decisions; it's to set direction and motivate others in the face of ambiguities and conflicting demands. Top executives must interpret information and communicate those interpretations--they must manage meaning more than they must manage information. So which of these competing views is the right one? Research conducted by academics Sutcliffe and Weber found that how accurate senior executives are about their competitive environments is indeed less important for strategy and corresponding organizational changes than the way in which they interpret information about their environments. Investments in shaping those interpretations, therefore, may create a more durable competitive advantage than investments in obtaining and organizing more information. And what kinds of interpretations are most closely linked with high performance? Their research suggests that high performers respond positively to opportunities, yet they aren't overconfident in their abilities to take advantage of those opportunities.

  8. Accurately measuring volcanic plume velocity with multiple UV spectrometers

    USGS Publications Warehouse

    Williams-Jones, Glyn; Horton, Keith A.; Elias, Tamar; Garbeil, Harold; Mouginis-Mark, Peter J; Sutton, A. Jeff; Harris, Andrew J. L.

    2006-01-01

    A fundamental problem with all ground-based remotely sensed measurements of volcanic gas flux is the difficulty in accurately measuring the velocity of the gas plume. Since a representative wind speed and direction are used as proxies for the actual plume velocity, there can be considerable uncertainty in reported gas flux values. Here we present a method that uses at least two time-synchronized simultaneously recording UV spectrometers (FLYSPECs) placed a known distance apart. By analyzing the time varying structure of SO2 concentration signals at each instrument, the plume velocity can accurately be determined. Experiments were conducted on Kīlauea (USA) and Masaya (Nicaragua) volcanoes in March and August 2003 at plume velocities between 1 and 10 m s−1. Concurrent ground-based anemometer measurements differed from FLYSPEC-measured plume speeds by up to 320%. This multi-spectrometer method allows for the accurate remote measurement of plume velocity and can therefore greatly improve the precision of volcanic or industrial gas flux measurements.

  9. Defining precision: The precision medicine initiative trials NCI-MPACT and NCI-MATCH.

    PubMed

    Coyne, Geraldine O'Sullivan; Takebe, Naoko; Chen, Alice P

    "Precision" trials, using rationally incorporated biomarker targets and molecularly selective anticancer agents, have become of great interest to both patients and their physicians. In the endeavor to test the cornerstone premise of precision oncotherapy, that is, determining if modulating a specific molecular aberration in a patient's tumor with a correspondingly specific therapeutic agent improves clinical outcomes, the design of clinical trials with embedded genomic characterization platforms which guide therapy are an increasing challenge. The National Cancer Institute Precision Medicine Initiative is an unprecedented large interdisciplinary collaborative effort to conceptualize and test the feasibility of trials incorporating sequencing platforms and large-scale bioinformatics processing that are not currently uniformly available to patients. National Cancer Institute-Molecular Profiling-based Assignment of Cancer Therapy and National Cancer Institute-Molecular Analysis for Therapy Choice are 2 genomic to phenotypic trials under this National Cancer Institute initiative, where treatment is selected according to predetermined genetic alterations detected using next-generation sequencing technology across a broad range of tumor types. In this article, we discuss the objectives and trial designs that have enabled the public-private partnerships required to complete the scale of both trials, as well as interim trial updates and strategic considerations that have driven data analysis and targeted therapy assignment, with the intent of elucidating further the benefits of this treatment approach for patients. Copyright © 2017. Published by Elsevier Inc.

  10. Delay times of a LiDAR-guided precision sprayer control system

    USDA-ARS?s Scientific Manuscript database

    Accurate flow control systems in triggering sprays against detected targets are needed for precision variable-rate sprayer development. System delay times due to the laser-sensor data buffer, software operation, and hydraulic-mechanical component response were determined for a control system used fo...

  11. Applications of an automated stem measurer for precision forestry

    Treesearch

    N. Clark

    2001-01-01

    Accurate stem measurements are required for the determination of many silvicultural prescriptions, i.e., what are we going to do with a stand of trees. This would only be amplified in a precision forestry context. Many methods have been proposed for optimal ways to evaluate stems for a variety of characteristics. These methods usually involve the acquisition of total...

  12. Anatomical brain images alone can accurately diagnose chronic neuropsychiatric illnesses.

    PubMed

    Bansal, Ravi; Staib, Lawrence H; Laine, Andrew F; Hao, Xuejun; Xu, Dongrong; Liu, Jun; Weissman, Myrna; Peterson, Bradley S

    2012-01-01

    Diagnoses using imaging-based measures alone offer the hope of improving the accuracy of clinical diagnosis, thereby reducing the costs associated with incorrect treatments. Previous attempts to use brain imaging for diagnosis, however, have had only limited success in diagnosing patients who are independent of the samples used to derive the diagnostic algorithms. We aimed to develop a classification algorithm that can accurately diagnose chronic, well-characterized neuropsychiatric illness in single individuals, given the availability of sufficiently precise delineations of brain regions across several neural systems in anatomical MR images of the brain. We have developed an automated method to diagnose individuals as having one of various neuropsychiatric illnesses using only anatomical MRI scans. The method employs a semi-supervised learning algorithm that discovers natural groupings of brains based on the spatial patterns of variation in the morphology of the cerebral cortex and other brain regions. We used split-half and leave-one-out cross-validation analyses in large MRI datasets to assess the reproducibility and diagnostic accuracy of those groupings. In MRI datasets from persons with Attention-Deficit/Hyperactivity Disorder, Schizophrenia, Tourette Syndrome, Bipolar Disorder, or persons at high or low familial risk for Major Depressive Disorder, our method discriminated with high specificity and nearly perfect sensitivity the brains of persons who had one specific neuropsychiatric disorder from the brains of healthy participants and the brains of persons who had a different neuropsychiatric disorder. Although the classification algorithm presupposes the availability of precisely delineated brain regions, our findings suggest that patterns of morphological variation across brain surfaces, extracted from MRI scans alone, can successfully diagnose the presence of chronic neuropsychiatric disorders. Extensions of these methods are likely to provide biomarkers

  13. Fundamentals of precision medicine

    PubMed Central

    Divaris, Kimon

    2018-01-01

    Imagine a world where clinicians make accurate diagnoses and provide targeted therapies to their patients according to well-defined, biologically-informed disease subtypes, accounting for individual differences in genetic make-up, behaviors, cultures, lifestyles and the environment. This is not as utopic as it may seem. Relatively recent advances in science and technology have led to an explosion of new information on what underlies health and what constitutes disease. These novel insights emanate from studies of the human genome and microbiome, their associated transcriptomes, proteomes and metabolomes, as well as epigenomics and exposomics—such ‘omics data can now be generated at unprecedented depth and scale, and at rapidly decreasing cost. Making sense and integrating these fundamental information domains to transform health care and improve health remains a challenge—an ambitious, laudable and high-yield goal. Precision dentistry is no longer a distant vision; it is becoming part of the rapidly evolving present. Insights from studies of the human genome and microbiome, their associated transcriptomes, proteomes and metabolomes, and epigenomics and exposomics have reached an unprecedented depth and scale. Much more needs to be done, however, for the realization of precision medicine in the oral health domain. PMID:29227115

  14. RESEARCH PROGRAM FOR BRACE - PROVIDING NO AND SPECIFIC NO2 MEASUREMENTS FOR THE BRACE DATABASE DURING THE MAY '02 FIELD STUDY

    EPA Science Inventory

    Three scientists from the EPA, RTP facility in Research Triangle Park, N.C. worked with the State of Florida and BRACE scientists to provide accurate and precise NO and specific NO2 measurements at two monitoring sites, the rural Sydney site and the near-bay, suburban Gandy sit...

  15. Precise monitoring of global temperature trends from satellites

    NASA Technical Reports Server (NTRS)

    Spencer, Roy W.; Christy, John R.

    1990-01-01

    Passive microwave radiometry from satellites provides more precise atmospheric temperature information than that obtained from the relatively sparse distribution of thermometers over the earth's surface. Accurate global atmospheric temperature estimates are needed for detection of possible greenhouse warming, evaluation of computer models of climate change, and for understanding important factors in the climate system. Analysis of the first 10 years (1979 to 1988) of satellite measurements of lower atmospheric temperature changes reveals a monthly precision of 0.01 C, large temperature variability on time scales from weeks to several years, but no obvious trend for the 10-year period. The warmest years, in descending order, were 1987, 1988, 1983, and 1980. The years 1984, 1985, and 1986 were the coolest.

  16. Quokka: a comprehensive tool for rapid and accurate prediction of kinase family-specific phosphorylation sites in the human proteome.

    PubMed

    Li, Fuyi; Li, Chen; Marquez-Lago, Tatiana T; Leier, André; Akutsu, Tatsuya; Purcell, Anthony W; Smith, A Ian; Lithgow, Trevor; Daly, Roger J; Song, Jiangning; Chou, Kuo-Chen

    2018-06-27

    Kinase-regulated phosphorylation is a ubiquitous type of post-translational modification (PTM) in both eukaryotic and prokaryotic cells. Phosphorylation plays fundamental roles in many signalling pathways and biological processes, such as protein degradation and protein-protein interactions. Experimental studies have revealed that signalling defects caused by aberrant phosphorylation are highly associated with a variety of human diseases, especially cancers. In light of this, a number of computational methods aiming to accurately predict protein kinase family-specific or kinase-specific phosphorylation sites have been established, thereby facilitating phosphoproteomic data analysis. In this work, we present Quokka, a novel bioinformatics tool that allows users to rapidly and accurately identify human kinase family-regulated phosphorylation sites. Quokka was developed by using a variety of sequence scoring functions combined with an optimized logistic regression algorithm. We evaluated Quokka based on well-prepared up-to-date benchmark and independent test datasets, curated from the Phospho.ELM and UniProt databases, respectively. The independent test demonstrates that Quokka improves the prediction performance compared with state-of-the-art computational tools for phosphorylation prediction. In summary, our tool provides users with high-quality predicted human phosphorylation sites for hypothesis generation and biological validation. The Quokka webserver and datasets are freely available at http://quokka.erc.monash.edu/. Supplementary data are available at Bioinformatics online.

  17. Relationship between HPLC precision and number of significant figures when reporting impurities and when setting specifications.

    PubMed

    Agut, Christophe; Segalini, Audrey; Bauer, Michel; Boccardi, Giovanni

    2006-05-03

    The rounding of an analytical result is a process that should take into account the uncertainty of the result, which is in turn assessed during the validation exercise. Rounding rules are known in physical and analytical chemistry since a long time, but are often not used or misused in pharmaceutical analysis. The paper describes the theoretical background of the most common rules and their application to fix the rounding of results and specifications. The paper makes use of uncertainty values of impurity determination acquired during studies of reproducibility and intermediate precision with regards to 22 impurities of drug substances or drug products. As a general rule, authors propose the use of sound and well-established rounding rules to derive rounding from the results of the validation package.

  18. GPS-based precision orbit determination - A Topex flight experiment

    NASA Technical Reports Server (NTRS)

    Melbourne, William G.; Davis, Edgar S.

    1988-01-01

    Plans for a Topex/Poseiden flight experiment to test the accuracy of using GPS data for precision orbit determination of earth satellites are presented. It is expected that the GPS-based precision orbit determination will provide subdecimeter accuracies in the radial component of the Topex orbit when the extant gravity model is tuned for wavelengths longer than about 1000 kms. The concept, design, flight receiver, antenna system, ground processing, and data processing of GPS are examined. Also, an accurate quasi-geometric orbit determination approach called nondynamic or reduced dynamic tracking which relies on the use of the pseudorange and the carrier phase measurements to reduce orbit errors arising from mismodeled dynamics is discussed.

  19. Precision Medicine, Cardiovascular Disease and Hunting Elephants.

    PubMed

    Joyner, Michael J

    2016-01-01

    Precision medicine postulates improved prediction, prevention, diagnosis and treatment of disease based on patient specific factors especially DNA sequence (i.e., gene) variants. Ideas related to precision medicine stem from the much anticipated "genetic revolution in medicine" arising seamlessly from the human genome project (HGP). In this essay I deconstruct the concept of precision medicine and raise questions about the validity of the paradigm in general and its application to cardiovascular disease. Thus far precision medicine has underperformed based on the vision promulgated by enthusiasts. While niche successes for precision medicine are likely, the promises of broad based transformation should be viewed with skepticism. Open discussion and debate related to precision medicine are urgently needed to avoid misapplication of resources, hype, iatrogenic interventions, and distraction from established approaches with ongoing utility. Failure to engage in such debate will lead to negative unintended consequences from a revolution that might never come. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. NCLscan: accurate identification of non-co-linear transcripts (fusion, trans-splicing and circular RNA) with a good balance between sensitivity and precision.

    PubMed

    Chuang, Trees-Juen; Wu, Chan-Shuo; Chen, Chia-Ying; Hung, Li-Yuan; Chiang, Tai-Wei; Yang, Min-Yu

    2016-02-18

    Analysis of RNA-seq data often detects numerous 'non-co-linear' (NCL) transcripts, which comprised sequence segments that are topologically inconsistent with their corresponding DNA sequences in the reference genome. However, detection of NCL transcripts involves two major challenges: removal of false positives arising from alignment artifacts and discrimination between different types of NCL transcripts (trans-spliced, circular or fusion transcripts). Here, we developed a new NCL-transcript-detecting method ('NCLscan'), which utilized a stepwise alignment strategy to almost completely eliminate false calls (>98% precision) without sacrificing true positives, enabling NCLscan outperform 18 other publicly-available tools (including fusion- and circular-RNA-detecting tools) in terms of sensitivity and precision, regardless of the generation strategy of simulated dataset, type of intragenic or intergenic NCL event, read depth of coverage, read length or expression level of NCL transcript. With the high accuracy, NCLscan was applied to distinguishing between trans-spliced, circular and fusion transcripts on the basis of poly(A)- and nonpoly(A)-selected RNA-seq data. We showed that circular RNAs were expressed more ubiquitously, more abundantly and less cell type-specifically than trans-spliced and fusion transcripts. Our study thus describes a robust pipeline for the discovery of NCL transcripts, and sheds light on the fundamental biology of these non-canonical RNA events in human transcriptome. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  1. An accurate and precise representation of drug ingredients.

    PubMed

    Hanna, Josh; Bian, Jiang; Hogan, William R

    2016-01-01

    In previous work, we built the Drug Ontology (DrOn) to support comparative effectiveness research use cases. Here, we have updated our representation of ingredients to include both active ingredients (and their strengths) and excipients. Our update had three primary lines of work: 1) analysing and extracting excipients, 2) analysing and extracting strength information for active ingredients, and 3) representing the binding of active ingredients to cytochrome P450 isoenzymes as substrates and inhibitors of those enzymes. To properly differentiate between excipients and active ingredients, we conducted an ontological analysis of the roles that various ingredients, including excipients, have in drug products. We used the value specification model of the Ontology for Biomedical Investigations to represent strengths of active ingredients and then analyzed RxNorm to extract excipient and strength information and modeled them according to the results of our analysis. We also analyzed and defined dispositions of molecules used in aggregate as active ingredients to bind cytochrome P450 isoenzymes. Our analysis of excipients led to 17 new classes representing the various roles that excipients can bear. We then extracted excipients from RxNorm and added them to DrOn for branded drugs. We found excipients for 5,743 branded drugs, covering ~27% of the 21,191 branded drugs in DrOn. Our analysis of active ingredients resulted in another new class, active ingredient role. We also extracted strengths for all types of tablets, capsules, and caplets, resulting in strengths for 5,782 drug forms, covering ~41% of the 14,035 total drug forms and accounting for ~97 % of the 5,970 tablets, capsules, and caplets in DrOn. We represented binding-as-substrate and binding-as-inhibitor dispositions to two cytochrome P450 (CYP) isoenzymes (CYP2C19 and CYP2D6) and linked these dispositions to 65 compounds. It is now possible to query DrOn automatically for all drug products that contain active

  2. Ultrathin conformal devices for precise and continuous thermal characterization of human skin

    NASA Astrophysics Data System (ADS)

    Webb, R. Chad; Bonifas, Andrew P.; Behnaz, Alex; Zhang, Yihui; Yu, Ki Jun; Cheng, Huanyu; Shi, Mingxing; Bian, Zuguang; Liu, Zhuangjian; Kim, Yun-Soung; Yeo, Woon-Hong; Park, Jae Suk; Song, Jizhou; Li, Yuhang; Huang, Yonggang; Gorbach, Alexander M.; Rogers, John A.

    2013-10-01

    Precision thermometry of the skin can, together with other measurements, provide clinically relevant information about cardiovascular health, cognitive state, malignancy and many other important aspects of human physiology. Here, we introduce an ultrathin, compliant skin-like sensor/actuator technology that can pliably laminate onto the epidermis to provide continuous, accurate thermal characterizations that are unavailable with other methods. Examples include non-invasive spatial mapping of skin temperature with millikelvin precision, and simultaneous quantitative assessment of tissue thermal conductivity. Such devices can also be implemented in ways that reveal the time-dynamic influence of blood flow and perfusion on these properties. Experimental and theoretical studies establish the underlying principles of operation, and define engineering guidelines for device design. Evaluation of subtle variations in skin temperature associated with mental activity, physical stimulation and vasoconstriction/dilation along with accurate determination of skin hydration through measurements of thermal conductivity represent some important operational examples.

  3. Precision Lifetime Measurements in Molecular Hydrogen

    NASA Astrophysics Data System (ADS)

    Ray, Mark D.

    1995-01-01

    We have measured the lifetimes of three rovibrational levels--g ^3Sigma_sp {g}{+}(v = 1,N = 2), i ^3{rm II}_sp{g} {-}(v = 0,N = 1), and j ^3Delta_sp{g}{-}(v = 1,N = 3)--in the n = 3 complex of para H _2 with a precision of 2%. The lifetimes are 8.66 +/- 0.16 ns for i ^3{rm II}_sp{g }{-}(v = 0, N = 1), 6.05+/- 0.11 ns for g ^3Sigma_sp {g}{+}(v = 1,N = 2), and 12.77 +/- 0.30 ns for j ^3 Delta_sp{g}{-}(v = 1,N = 3). On the basis of the first two measurements, we suggest that a previously neglected decay channel should be included in theoretical treatments and may have played an important role in an earlier experiment. Our value for the lifetime of j ^3Delta _sp{g}{-}(v = 1,N = 3) agrees well with the earlier experiment; the best theoretical estimate lies almost 50% higher. The measurements are done in a molecular beam via laser photoionization. An intense beam of metastable (2p) c ^3{rm II}_sp {u}{-} levels is created by electron bombardment. Downstream, a specific rotational -vibrational level of an n = 3 electronic state is excited by a resonant laser. After a delay, the remaining population is photoionized by a second laser. By measuring the photoionization yield as a function of the delay between the exciting and photoionizing lasers, we are able to determine the lifetime of the excited level. With a few modifications to the experimental apparatus, we believe it is possible to measure lifetimes at the 0.5% level of precision. We also propose the use of muti-channel quantum defect theory to obtain accurate ab initio decay rates for some of the branches involved.

  4. Accuracy and precision of protein-ligand interaction kinetics determined from chemical shift titrations.

    PubMed

    Markin, Craig J; Spyracopoulos, Leo

    2012-12-01

    NMR-monitored chemical shift titrations for the study of weak protein-ligand interactions represent a rich source of information regarding thermodynamic parameters such as dissociation constants (K ( D )) in the micro- to millimolar range, populations for the free and ligand-bound states, and the kinetics of interconversion between states, which are typically within the fast exchange regime on the NMR timescale. We recently developed two chemical shift titration methods wherein co-variation of the total protein and ligand concentrations gives increased precision for the K ( D ) value of a 1:1 protein-ligand interaction (Markin and Spyracopoulos in J Biomol NMR 53: 125-138, 2012). In this study, we demonstrate that classical line shape analysis applied to a single set of (1)H-(15)N 2D HSQC NMR spectra acquired using precise protein-ligand chemical shift titration methods we developed, produces accurate and precise kinetic parameters such as the off-rate (k ( off )). For experimentally determined kinetics in the fast exchange regime on the NMR timescale, k ( off ) ~ 3,000 s(-1) in this work, the accuracy of classical line shape analysis was determined to be better than 5 % by conducting quantum mechanical NMR simulations of the chemical shift titration methods with the magnetic resonance toolkit GAMMA. Using Monte Carlo simulations, the experimental precision for k ( off ) from line shape analysis of NMR spectra was determined to be 13 %, in agreement with the theoretical precision of 12 % from line shape analysis of the GAMMA simulations in the presence of noise and protein concentration errors. In addition, GAMMA simulations were employed to demonstrate that line shape analysis has the potential to provide reasonably accurate and precise k ( off ) values over a wide range, from 100 to 15,000 s(-1). The validity of line shape analysis for k ( off ) values approaching intermediate exchange (~100 s(-1)), may be facilitated by more accurate K ( D ) measurements

  5. Precision Medicine in Multiple Sclerosis: Future of PET Imaging of Inflammation and Reactive Astrocytes

    PubMed Central

    Poutiainen, Pekka; Jaronen, Merja; Quintana, Francisco J.; Brownell, Anna-Liisa

    2016-01-01

    Non-invasive molecular imaging techniques can enhance diagnosis to achieve successful treatment, as well as reveal underlying pathogenic mechanisms in disorders such as multiple sclerosis (MS). The cooperation of advanced multimodal imaging techniques and increased knowledge of the MS disease mechanism allows both monitoring of neuronal network and therapeutic outcome as well as the tools to discover novel therapeutic targets. Diverse imaging modalities provide reliable diagnostic and prognostic platforms to better achieve precision medicine. Traditionally, magnetic resonance imaging (MRI) has been considered the golden standard in MS research and diagnosis. However, positron emission tomography (PET) imaging can provide functional information of molecular biology in detail even prior to anatomic changes, allowing close follow up of disease progression and treatment response. The recent findings support three major neuroinflammation components in MS: astrogliosis, cytokine elevation, and significant changes in specific proteins, which offer a great variety of specific targets for imaging purposes. Regardless of the fact that imaging of astrocyte function is still a young field and in need for development of suitable imaging ligands, recent studies have shown that inflammation and astrocyte activation are related to progression of MS. MS is a complex disease, which requires understanding of disease mechanisms for successful treatment. PET is a precise non-invasive imaging method for biochemical functions and has potential to enhance early and accurate diagnosis for precision therapy of MS. In this review we focus on modulation of different receptor systems and inflammatory aspect of MS, especially on activation of glial cells, and summarize the recent findings of PET imaging in MS and present the most potent targets for new biomarkers with the main focus on experimental MS research. PMID:27695400

  6. Rapid and precise determination of ATP using a modified photometer

    USGS Publications Warehouse

    Shultz, David J.; Stephens, Doyle W.

    1980-01-01

    An inexpensive delay timer was designed to modify a commercially available ATP photometer which allows a disposable tip pipette to be used for injecting either enzyme or sample into the reaction cuvette. The disposable tip pipette is as precise and accurate as a fixed-needle syringe but eliminates the problem of sample contamination and decreases analytical time. (USGS)

  7. ACCURATE ORBITAL INTEGRATION OF THE GENERAL THREE-BODY PROBLEM BASED ON THE D'ALEMBERT-TYPE SCHEME

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

    Minesaki, Yukitaka

    2013-03-15

    We propose an accurate orbital integration scheme for the general three-body problem that retains all conserved quantities except angular momentum. The scheme is provided by an extension of the d'Alembert-type scheme for constrained autonomous Hamiltonian systems. Although the proposed scheme is merely second-order accurate, it can precisely reproduce some periodic, quasiperiodic, and escape orbits. The Levi-Civita transformation plays a role in designing the scheme.

  8. Precision Landing and Hazard Avoidance Doman

    NASA Technical Reports Server (NTRS)

    Robertson, Edward A.; Carson, John M., III

    2016-01-01

    The Precision Landing and Hazard Avoidance (PL&HA) domain addresses the development, integration, testing, and spaceflight infusion of sensing, processing, and GN&C functions critical to the success and safety of future human and robotic exploration missions. PL&HA sensors also have applications to other mission events, such as rendezvous and docking. Autonomous PL&HA builds upon the core GN&C capabilities developed to enable soft, controlled landings on the Moon, Mars, and other solar system bodies. Through the addition of a Terrain Relative Navigation (TRN) function, precision landing within tens of meters of a map-based target is possible. The addition of a 3-D terrain mapping lidar sensor improves the probability of a safe landing via autonomous, real-time Hazard Detection and Avoidance (HDA). PL&HA significantly improves the probability of mission success and enhances access to sites of scientific interest located in challenging terrain. PL&HA can also utilize external navigation aids, such as navigation satellites and surface beacons. Advanced Lidar Sensors High precision ranging, velocimetry, and 3-D terrain mapping Terrain Relative Navigation (TRN) TRN compares onboard reconnaissance data with real-time terrain imaging data to update the S/C position estimate Hazard Detection and Avoidance (HDA) Generates a high-resolution, 3-D terrain map in real-time during the approach trajectory to identify safe landing targets Inertial Navigation During Terminal Descent High precision surface relative sensors enable accurate inertial navigation during terminal descent and a tightly controlled touchdown within meters of the selected safe landing target.

  9. Universal precision sine bar attachment

    NASA Technical Reports Server (NTRS)

    Mann, Franklin D. (Inventor)

    1989-01-01

    This invention relates to an attachment for a sine bar which can be used to perform measurements during lathe operations or other types of machining operations. The attachment can be used for setting precision angles on vises, dividing heads, rotary tables and angle plates. It can also be used in the inspection of machined parts, when close tolerances are required, and in the layout of precision hardware. The novelty of the invention is believed to reside in a specific versatile sine bar attachment for measuring a variety of angles on a number of different types of equipment.

  10. Theranostics of prostate cancer: from molecular imaging to precision molecular radiotherapy targeting the prostate specific membrane antigen.

    PubMed

    Kulkarni, Harshad R; Singh, Aviral; Langbein, Thomas; Schuchardt, Christiane; Mueller, Dirk; Zhang, Jingjing; Lehmann, Coline; Baum, Richard P

    2018-06-01

    Alterations at the molecular level are a hallmark of cancer. Prostate cancer is associated with the overexpression of prostate-specific membrane antigen (PSMA) in a majority of cases, predominantly in advanced tumors, increasing with the grade or Gleason's score. PSMA can be selectively targeted using radiolabeled PSMA ligands. These small molecules binding the PSMA can be radiolabeled with γ-emitters like 99m Tc and 111 In or positron emitters like 68 Ga and 18 F for diagnosis as well as with their theranostic pairs such as 177 Lu (β-emitter) or 225 Ac (α-emitter) for therapy. This review summarizes the theranostic role of PSMA ligands for molecular imaging and targeted molecular radiotherapy, moving towards precision oncology.

  11. Mechanism and experimental research on ultra-precision grinding of ferrite

    NASA Astrophysics Data System (ADS)

    Ban, Xinxing; Zhao, Huiying; Dong, Longchao; Zhu, Xueliang; Zhang, Chupeng; Gu, Yawen

    2017-02-01

    Ultra-precision grinding of ferrite is conducted to investigate the removal mechanism. Effect of the accuracy of machine tool key components on grinding surface quality is analyzed. The surface generation model of ferrite ultra-precision grinding machining is established. In order to reveal the surface formation mechanism of ferrite in the process of ultraprecision grinding, furthermore, the scientific and accurate of the calculation model are taken into account to verify the grinding surface roughness, which is proposed. Orthogonal experiment is designed using the high precision aerostatic turntable and aerostatic spindle for ferrite which is a typical hard brittle materials. Based on the experimental results, the influence factors and laws of ultra-precision grinding surface of ferrite are discussed through the analysis of the surface roughness. The results show that the quality of ferrite grinding surface is the optimal parameters, when the wheel speed of 20000r/mm, feed rate of 10mm/min, grinding depth of 0.005mm, and turntable rotary speed of 5r/min, the surface roughness Ra can up to 75nm.

  12. Chapter 10: Precision Agriculture for Sustainability and Environmental Protection

    USDA-ARS?s Scientific Manuscript database

    Available supplies of water for irrigation and other uses are becoming more limited around the world, and this trend is accelerating. Emerging computerized precision irrigation technologies will enable growers to apply water and agrochemicals more precisely and site-specifically to match the status...

  13. High precision NC lathe feeding system rigid-flexible coupling model reduction technology

    NASA Astrophysics Data System (ADS)

    Xuan, He; Hua, Qingsong; Cheng, Lianjun; Zhang, Hongxin; Zhao, Qinghai; Mao, Xinkai

    2017-08-01

    This paper proposes the use of dynamic substructure method of reduction of order to achieve effective reduction of feed system for high precision NC lathe feeding system rigid-flexible coupling model, namely the use of ADAMS to establish the rigid flexible coupling simulation model of high precision NC lathe, and then the vibration simulation of the period by using the FD 3D damper is very effective for feed system of bolt connection reduction of multi degree of freedom model. The vibration simulation calculation is more accurate, more quickly.

  14. The Use of Scale-Dependent Precision to Increase Forecast Accuracy in Earth System Modelling

    NASA Astrophysics Data System (ADS)

    Thornes, Tobias; Duben, Peter; Palmer, Tim

    2016-04-01

    At the current pace of development, it may be decades before the 'exa-scale' computers needed to resolve individual convective clouds in weather and climate models become available to forecasters, and such machines will incur very high power demands. But the resolution could be improved today by switching to more efficient, 'inexact' hardware with which variables can be represented in 'reduced precision'. Currently, all numbers in our models are represented as double-precision floating points - each requiring 64 bits of memory - to minimise rounding errors, regardless of spatial scale. Yet observational and modelling constraints mean that values of atmospheric variables are inevitably known less precisely on smaller scales, suggesting that this may be a waste of computer resources. More accurate forecasts might therefore be obtained by taking a scale-selective approach whereby the precision of variables is gradually decreased at smaller spatial scales to optimise the overall efficiency of the model. To study the effect of reducing precision to different levels on multiple spatial scales, we here introduce a new model atmosphere developed by extending the Lorenz '96 idealised system to encompass three tiers of variables - which represent large-, medium- and small-scale features - for the first time. In this chaotic but computationally tractable system, the 'true' state can be defined by explicitly resolving all three tiers. The abilities of low resolution (single-tier) double-precision models and similar-cost high resolution (two-tier) models in mixed-precision to produce accurate forecasts of this 'truth' are compared. The high resolution models outperform the low resolution ones even when small-scale variables are resolved in half-precision (16 bits). This suggests that using scale-dependent levels of precision in more complicated real-world Earth System models could allow forecasts to be made at higher resolution and with improved accuracy. If adopted, this new

  15. [Precision nutrition in the era of precision medicine].

    PubMed

    Chen, P Z; Wang, H

    2016-12-06

    Precision medicine has been increasingly incorporated into clinical practice and is enabling a new era for disease prevention and treatment. As an important constituent of precision medicine, precision nutrition has also been drawing more attention during physical examinations. The main aim of precision nutrition is to provide safe and efficient intervention methods for disease treatment and management, through fully considering the genetics, lifestyle (dietary, exercise and lifestyle choices), metabolic status, gut microbiota and physiological status (nutrient level and disease status) of individuals. Three major components should be considered in precision nutrition, including individual criteria for sufficient nutritional status, biomarker monitoring or techniques for nutrient detection and the applicable therapeutic or intervention methods. It was suggested that, in clinical practice, many inherited and chronic metabolic diseases might be prevented or managed through precision nutritional intervention. For generally healthy populations, because lifestyles, dietary factors, genetic factors and environmental exposures vary among individuals, precision nutrition is warranted to improve their physical activity and reduce disease risks. In summary, research and practice is leading toward precision nutrition becoming an integral constituent of clinical nutrition and disease prevention in the era of precision medicine.

  16. Ultrathin conformal devices for precise and continuous thermal characterization of human skin

    PubMed Central

    Webb, R. Chad; Bonifas, Andrew P.; Behnaz, Alex; Zhang, Yihui; Yu, Ki Jun; Cheng, Huanyu; Shi, Mingxing; Bian, Zuguang; Liu, Zhuangjian; Kim, Yun-Soung; Yeo, Woon-Hong; Park, Jae Suk; Song, Jizhou; Li, Yuhang; Huang, Yonggang; Gorbach, Alexander M.; Rogers, John A.

    2013-01-01

    Precision thermometry of the skin can, together with other measurements, provide clinically relevant information about cardiovascular health, cognitive state, malignancy and many other important aspects of human physiology. Here, we introduce an ultrathin, compliant skin-like sensor/actuator technology that can pliably laminate onto the epidermis to provide continuous, accurate thermal characterizations that are unavailable with other methods. Examples include non-invasive spatial mapping of skin temperature with millikelvin precision, and simultaneous quantitative assessment of tissue thermal conductivity. Such devices can also be implemented in ways that reveal the time-dynamic influence of blood flow and perfusion on these properties. Experimental and theoretical studies establish the underlying principles of operation, and define engineering guidelines for device design. Evaluation of subtle variations in skin temperature associated with mental activity, physical stimulation and vasoconstriction/dilation along with accurate determination of skin hydration through measurements of thermal conductivity represent some important operational examples. PMID:24037122

  17. Accurate quantification of magnetic particle properties by intra-pair magnetophoresis for nanobiotechnology

    NASA Astrophysics Data System (ADS)

    van Reenen, Alexander; Gao, Yang; Bos, Arjen H.; de Jong, Arthur M.; Hulsen, Martien A.; den Toonder, Jaap M. J.; Prins, Menno W. J.

    2013-07-01

    The application of magnetic particles in biomedical research and in-vitro diagnostics requires accurate characterization of their magnetic properties, with single-particle resolution and good statistics. Here, we report intra-pair magnetophoresis as a method to accurately quantify the field-dependent magnetic moments of magnetic particles and to rapidly generate histograms of the magnetic moments with good statistics. We demonstrate our method with particles of different sizes and from different sources, with a measurement precision of a few percent. We expect that intra-pair magnetophoresis will be a powerful tool for the characterization and improvement of particles for the upcoming field of particle-based nanobiotechnology.

  18. Precision Oncology beyond Targeted Therapy: Combining Omics Data with Machine Learning Matches the Majority of Cancer Cells to Effective Therapeutics.

    PubMed

    Ding, Michael Q; Chen, Lujia; Cooper, Gregory F; Young, Jonathan D; Lu, Xinghua

    2018-02-01

    Precision oncology involves identifying drugs that will effectively treat a tumor and then prescribing an optimal clinical treatment regimen. However, most first-line chemotherapy drugs do not have biomarkers to guide their application. For molecularly targeted drugs, using the genomic status of a drug target as a therapeutic indicator has limitations. In this study, machine learning methods (e.g., deep learning) were used to identify informative features from genome-scale omics data and to train classifiers for predicting the effectiveness of drugs in cancer cell lines. The methodology introduced here can accurately predict the efficacy of drugs, regardless of whether they are molecularly targeted or nonspecific chemotherapy drugs. This approach, on a per-drug basis, can identify sensitive cancer cells with an average sensitivity of 0.82 and specificity of 0.82; on a per-cell line basis, it can identify effective drugs with an average sensitivity of 0.80 and specificity of 0.82. This report describes a data-driven precision medicine approach that is not only generalizable but also optimizes therapeutic efficacy. The framework detailed herein, when successfully translated to clinical environments, could significantly broaden the scope of precision oncology beyond targeted therapies, benefiting an expanded proportion of cancer patients. Mol Cancer Res; 16(2); 269-78. ©2017 AACR . ©2017 American Association for Cancer Research.

  19. Accurate age estimation in small-scale societies

    PubMed Central

    Smith, Daniel; Gerbault, Pascale; Dyble, Mark; Migliano, Andrea Bamberg; Thomas, Mark G.

    2017-01-01

    Precise estimation of age is essential in evolutionary anthropology, especially to infer population age structures and understand the evolution of human life history diversity. However, in small-scale societies, such as hunter-gatherer populations, time is often not referred to in calendar years, and accurate age estimation remains a challenge. We address this issue by proposing a Bayesian approach that accounts for age uncertainty inherent to fieldwork data. We developed a Gibbs sampling Markov chain Monte Carlo algorithm that produces posterior distributions of ages for each individual, based on a ranking order of individuals from youngest to oldest and age ranges for each individual. We first validate our method on 65 Agta foragers from the Philippines with known ages, and show that our method generates age estimations that are superior to previously published regression-based approaches. We then use data on 587 Agta collected during recent fieldwork to demonstrate how multiple partial age ranks coming from multiple camps of hunter-gatherers can be integrated. Finally, we exemplify how the distributions generated by our method can be used to estimate important demographic parameters in small-scale societies: here, age-specific fertility patterns. Our flexible Bayesian approach will be especially useful to improve cross-cultural life history datasets for small-scale societies for which reliable age records are difficult to acquire. PMID:28696282

  20. Accurate age estimation in small-scale societies.

    PubMed

    Diekmann, Yoan; Smith, Daniel; Gerbault, Pascale; Dyble, Mark; Page, Abigail E; Chaudhary, Nikhil; Migliano, Andrea Bamberg; Thomas, Mark G

    2017-08-01

    Precise estimation of age is essential in evolutionary anthropology, especially to infer population age structures and understand the evolution of human life history diversity. However, in small-scale societies, such as hunter-gatherer populations, time is often not referred to in calendar years, and accurate age estimation remains a challenge. We address this issue by proposing a Bayesian approach that accounts for age uncertainty inherent to fieldwork data. We developed a Gibbs sampling Markov chain Monte Carlo algorithm that produces posterior distributions of ages for each individual, based on a ranking order of individuals from youngest to oldest and age ranges for each individual. We first validate our method on 65 Agta foragers from the Philippines with known ages, and show that our method generates age estimations that are superior to previously published regression-based approaches. We then use data on 587 Agta collected during recent fieldwork to demonstrate how multiple partial age ranks coming from multiple camps of hunter-gatherers can be integrated. Finally, we exemplify how the distributions generated by our method can be used to estimate important demographic parameters in small-scale societies: here, age-specific fertility patterns. Our flexible Bayesian approach will be especially useful to improve cross-cultural life history datasets for small-scale societies for which reliable age records are difficult to acquire.

  1. Precision Therapy of Head and Neck Squamous Cell Carcinoma.

    PubMed

    Polverini, P J; D'Silva, N J; Lei, Y L

    2018-06-01

    Precision medicine is an approach to disease prevention and treatment that takes into account genetic variability and environmental and lifestyle influences that are unique to each patient. It facilitates stratification of patient populations that vary in their susceptibility to disease and response to therapy. Shared databases and the implementation of new technology systems designed to advance the integration of this information will enable health care providers to more accurately predict and customize prevention and treatment strategies for patients. Although precision medicine has had a limited impact in most areas of medicine, it has been shown to be an increasingly successful approach to cancer therapy. Despite early promising results targeting aberrant signaling pathways or inhibitors designed to block tumor-driven processes such as angiogenesis, limited success emphasizes the need to discover new biomarkers and treatment targets that are more reliable in predicting response to therapy and result in better health outcomes. Recent successes in the use of immunity-inducing antibodies have stimulated increased interest in the use of precision immunotherapy of head and neck squamous cell carcinoma. Using next-generation sequencing, the precise profiling of tumor-infiltrating lymphocytes has great promise to identify hypoimmunogenic cancer that would benefit from a rationally designed combinatorial approach. Continued interrogation of tumors will reveal new actionable targets with increasing therapeutic efficacy and fulfill the promise of precision therapy of head and neck cancer.

  2. Atomically Precise Interfaces from Non-stoichiometric Deposition

    NASA Astrophysics Data System (ADS)

    Nie, Yuefeng; Zhu, Ye; Lee, Che-Hui; Kourkoutis, Lena; Mundy, Julia; Junquera, Javier; Ghosez, Philippe; Baek, David; Sung, Suk Hyun; Xi, Xiaoxing; Shen, Kyle; Muller, David; Schlom, Darrell

    2015-03-01

    Complex oxide heterostructures display some of the most chemically abrupt, atomically precise interfaces, which is advantageous when constructing new interface phases with emergent properties by juxtaposing incompatible ground states. One might assume that atomically precise interfaces result from stoichiometric growth. Here we show that the most precise control is, however, obtained by using deliberate and specific non-stoichiometric growth conditions. For the precise growth of Srn+1TinO3n+1 Ruddlesden-Popper (RP) phases, stoichiometric deposition leads to the loss of the first RP rock-salt double layer, but growing with a strontium-rich surface layer restores the bulk stoichiometry and ordering of the subsurface RP structure. Our results dramatically expand the materials that can be prepared in epitaxial heterostructures with precise interface control--from just the n = 1 end members (perovskites) to the entire RP homologous series--enabling the exploration of novel quantum phenomena at a richer variety of oxide interfaces.

  3. Atomically precise interfaces from non-stoichiometric deposition

    NASA Astrophysics Data System (ADS)

    Nie, Y. F.; Zhu, Y.; Lee, C.-H.; Kourkoutis, L. F.; Mundy, J. A.; Junquera, J.; Ghosez, Ph.; Baek, D. J.; Sung, S.; Xi, X. X.; Shen, K. M.; Muller, D. A.; Schlom, D. G.

    2014-08-01

    Complex oxide heterostructures display some of the most chemically abrupt, atomically precise interfaces, which is advantageous when constructing new interface phases with emergent properties by juxtaposing incompatible ground states. One might assume that atomically precise interfaces result from stoichiometric growth. Here we show that the most precise control is, however, obtained by using deliberate and specific non-stoichiometric growth conditions. For the precise growth of Srn+1TinOn+1 Ruddlesden-Popper (RP) phases, stoichiometric deposition leads to the loss of the first RP rock-salt double layer, but growing with a strontium-rich surface layer restores the bulk stoichiometry and ordering of the subsurface RP structure. Our results dramatically expand the materials that can be prepared in epitaxial heterostructures with precise interface control—from just the n=∞ end members (perovskites) to the entire RP homologous series—enabling the exploration of novel quantum phenomena at a richer variety of oxide interfaces.

  4. Laser-Induced Focused Ultrasound for Cavitation Treatment: Toward High-Precision Invisible Sonic Scalpel.

    PubMed

    Lee, Taehwa; Luo, Wei; Li, Qiaochu; Demirci, Hakan; Guo, L Jay

    2017-10-01

    Beyond the implementation of the photoacoustic effect to photoacoustic imaging and laser ultrasonics, this study demonstrates a novel application of the photoacoustic effect for high-precision cavitation treatment of tissue using laser-induced focused ultrasound. The focused ultrasound is generated by pulsed optical excitation of an efficient photoacoustic film coated on a concave surface, and its amplitude is high enough to produce controllable microcavitation within the focal region (lateral focus <100 µm). Such microcavitation is used to cut or ablate soft tissue in a highly precise manner. This work demonstrates precise cutting of tissue-mimicking gels as well as accurate ablation of gels and animal eye tissues. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Precision Health Economics and Outcomes Research to Support Precision Medicine: Big Data Meets Patient Heterogeneity on the Road to Value.

    PubMed

    Chen, Yixi; Guzauskas, Gregory F; Gu, Chengming; Wang, Bruce C M; Furnback, Wesley E; Xie, Guotong; Dong, Peng; Garrison, Louis P

    2016-11-02

    The "big data" era represents an exciting opportunity to utilize powerful new sources of information to reduce clinical and health economic uncertainty on an individual patient level. In turn, health economic outcomes research (HEOR) practices will need to evolve to accommodate individual patient-level HEOR analyses. We propose the concept of "precision HEOR", which utilizes a combination of costs and outcomes derived from big data to inform healthcare decision-making that is tailored to highly specific patient clusters or individuals. To explore this concept, we discuss the current and future roles of HEOR in health sector decision-making, big data and predictive analytics, and several key HEOR contexts in which big data and predictive analytics might transform traditional HEOR into precision HEOR. The guidance document addresses issues related to the transition from traditional to precision HEOR practices, the evaluation of patient similarity analysis and its appropriateness for precision HEOR analysis, and future challenges to precision HEOR adoption. Precision HEOR should make precision medicine more realizable by aiding and adapting healthcare resource allocation. The combined hopes for precision medicine and precision HEOR are that individual patients receive the best possible medical care while overall healthcare costs remain manageable or become more cost-efficient.

  6. Precision Health Economics and Outcomes Research to Support Precision Medicine: Big Data Meets Patient Heterogeneity on the Road to Value

    PubMed Central

    Chen, Yixi; Guzauskas, Gregory F.; Gu, Chengming; Wang, Bruce C. M.; Furnback, Wesley E.; Xie, Guotong; Dong, Peng; Garrison, Louis P.

    2016-01-01

    The “big data” era represents an exciting opportunity to utilize powerful new sources of information to reduce clinical and health economic uncertainty on an individual patient level. In turn, health economic outcomes research (HEOR) practices will need to evolve to accommodate individual patient–level HEOR analyses. We propose the concept of “precision HEOR”, which utilizes a combination of costs and outcomes derived from big data to inform healthcare decision-making that is tailored to highly specific patient clusters or individuals. To explore this concept, we discuss the current and future roles of HEOR in health sector decision-making, big data and predictive analytics, and several key HEOR contexts in which big data and predictive analytics might transform traditional HEOR into precision HEOR. The guidance document addresses issues related to the transition from traditional to precision HEOR practices, the evaluation of patient similarity analysis and its appropriateness for precision HEOR analysis, and future challenges to precision HEOR adoption. Precision HEOR should make precision medicine more realizable by aiding and adapting healthcare resource allocation. The combined hopes for precision medicine and precision HEOR are that individual patients receive the best possible medical care while overall healthcare costs remain manageable or become more cost-efficient. PMID:27827859

  7. Big Data's Role in Precision Public Health.

    PubMed

    Dolley, Shawn

    2018-01-01

    Precision public health is an emerging practice to more granularly predict and understand public health risks and customize treatments for more specific and homogeneous subpopulations, often using new data, technologies, and methods. Big data is one element that has consistently helped to achieve these goals, through its ability to deliver to practitioners a volume and variety of structured or unstructured data not previously possible. Big data has enabled more widespread and specific research and trials of stratifying and segmenting populations at risk for a variety of health problems. Examples of success using big data are surveyed in surveillance and signal detection, predicting future risk, targeted interventions, and understanding disease. Using novel big data or big data approaches has risks that remain to be resolved. The continued growth in volume and variety of available data, decreased costs of data capture, and emerging computational methods mean big data success will likely be a required pillar of precision public health into the future. This review article aims to identify the precision public health use cases where big data has added value, identify classes of value that big data may bring, and outline the risks inherent in using big data in precision public health efforts.

  8. Accurate estimation of sigma(exp 0) using AIRSAR data

    NASA Technical Reports Server (NTRS)

    Holecz, Francesco; Rignot, Eric

    1995-01-01

    During recent years signature analysis, classification, and modeling of Synthetic Aperture Radar (SAR) data as well as estimation of geophysical parameters from SAR data have received a great deal of interest. An important requirement for the quantitative use of SAR data is the accurate estimation of the backscattering coefficient sigma(exp 0). In terrain with relief variations radar signals are distorted due to the projection of the scene topography into the slant range-Doppler plane. The effect of these variations is to change the physical size of the scattering area, leading to errors in the radar backscatter values and incidence angle. For this reason the local incidence angle, derived from sensor position and Digital Elevation Model (DEM) data must always be considered. Especially in the airborne case, the antenna gain pattern can be an additional source of radiometric error, because the radar look angle is not known precisely as a result of the the aircraft motions and the local surface topography. Consequently, radiometric distortions due to the antenna gain pattern must also be corrected for each resolution cell, by taking into account aircraft displacements (position and attitude) and position of the backscatter element, defined by the DEM data. In this paper, a method to derive an accurate estimation of the backscattering coefficient using NASA/JPL AIRSAR data is presented. The results are evaluated in terms of geometric accuracy, radiometric variations of sigma(exp 0), and precision of the estimated forest biomass.

  9. Collaborative Genomics Study Advances Precision Oncology

    Cancer.gov

    A collaborative study conducted by two Office of Cancer Genomics (OCG) initiatives highlights the importance of integrating structural and functional genomics programs to improve cancer therapies, and more specifically, contribute to precision oncology treatments for children.

  10. In situ, accurate, surface-enhanced Raman scattering detection of cancer cell nucleus with synchronous location by an alkyne-labeled biomolecular probe.

    PubMed

    Zhang, Jing; Liang, Lijia; Guan, Xin; Deng, Rong; Qu, Huixin; Huang, Dianshuai; Xu, Shuping; Liang, Chongyang; Xu, Weiqing

    2018-01-01

    A surface-enhanced Raman scattering (SERS) method for in situ detection and analysis of the intranuclear biomolecular information of a cell has been developed based on a small, biocompatible, nuclear-targeting alkyne-tagged deoxyribonucleic acid (DNA) probe (5-ethynyl-2'-deoxyuridine, EDU) that can specially accumulate in the cell nucleus during DNA replications to precisely locate the nuclear region without disturbance in cell biological activities and functions. Since the specific alkyne group shows a Raman peak in the Raman-silent region of cells, it is an interior label to visualize the nuclear location synchronously in real time when measuring the SERS spectra of a cell. Because no fluorescent-labeled dyes were used for locating cell nuclei, this method is simple, nondestructive, non- photobleaching, and valuable for the in situ exploration of vital physiological processes with DNA participation in cell organelles. Graphical abstract A universal strategy was developed to accurately locate the nuclear region and obtain precise molecular information of cell nuclei by SERS.

  11. Precision forging technology for aluminum alloy

    NASA Astrophysics Data System (ADS)

    Deng, Lei; Wang, Xinyun; Jin, Junsong; Xia, Juchen

    2018-03-01

    Aluminum alloy is a preferred metal material for lightweight part manufacturing in aerospace, automobile, and weapon industries due to its good physical properties, such as low density, high specific strength, and good corrosion resistance. However, during forging processes, underfilling, folding, broken streamline, crack, coarse grain, and other macro- or microdefects are easily generated because of the deformation characteristics of aluminum alloys, including narrow forgeable temperature region, fast heat dissipation to dies, strong adhesion, high strain rate sensitivity, and large flow resistance. Thus, it is seriously restricted for the forged part to obtain precision shape and enhanced property. In this paper, progresses in precision forging technologies of aluminum alloy parts were reviewed. Several advanced precision forging technologies have been developed, including closed die forging, isothermal die forging, local loading forging, metal flow forging with relief cavity, auxiliary force or vibration loading, casting-forging hybrid forming, and stamping-forging hybrid forming. High-precision aluminum alloy parts can be realized by controlling the forging processes and parameters or combining precision forging technologies with other forming technologies. The development of these technologies is beneficial to promote the application of aluminum alloys in manufacturing of lightweight parts.

  12. Tool simplifies machining of pipe ends for precision welding

    NASA Technical Reports Server (NTRS)

    Matus, S. T.

    1969-01-01

    Single tool prepares a pipe end for precision welding by simultaneously performing internal machining, end facing, and bevel cutting to specification standards. The machining operation requires only one milling adjustment, can be performed quickly, and produces the high quality pipe-end configurations required to ensure precision-welded joints.

  13. An accurate bacterial DNA quantification assay for HTS library preparation of human biological samples.

    PubMed

    Seashols-Williams, Sarah; Green, Raquel; Wohlfahrt, Denise; Brand, Angela; Tan-Torres, Antonio Limjuco; Nogales, Francy; Brooks, J Paul; Singh, Baneshwar

    2018-05-17

    Sequencing and classification of microbial taxa within forensically relevant biological fluids has the potential for applications in the forensic science and biomedical fields. The quantity of bacterial DNA from human samples is currently estimated based on quantity of total DNA isolated. This method can miscalculate bacterial DNA quantity due to the mixed nature of the sample, and consequently library preparation is often unreliable. We developed an assay that can accurately and specifically quantify bacterial DNA within a mixed sample for reliable 16S ribosomal DNA (16S rDNA) library preparation and high throughput sequencing (HTS). A qPCR method was optimized using universal 16S rDNA primers, and a commercially available bacterial community DNA standard was used to develop a precise standard curve. Following qPCR optimization, 16S rDNA libraries from saliva, vaginal and menstrual secretions, urine, and fecal matter were amplified and evaluated at various DNA concentrations; successful HTS data were generated with as low as 20 pg of bacterial DNA. Changes in bacterial DNA quantity did not impact observed relative abundances of major bacterial taxa, but relative abundance changes of minor taxa were observed. Accurate quantification of microbial DNA resulted in consistent, successful library preparations for HTS analysis. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Precision Medicine and PET/Computed Tomography: Challenges and Implementation.

    PubMed

    Subramaniam, Rathan M

    2017-01-01

    Precision Medicine is about selecting the right therapy for the right patient, at the right time, specific to the molecular targets expressed by disease or tumors, in the context of patient's environment and lifestyle. Some of the challenges for delivery of precision medicine in oncology include biomarkers for patient selection for enrichment-precision diagnostics, mapping out tumor heterogeneity that contributes to therapy failures, and early therapy assessment to identify resistance to therapies. PET/computed tomography offers solutions in these important areas of challenges and facilitates implementation of precision medicine. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Accurately estimating PSF with straight lines detected by Hough transform

    NASA Astrophysics Data System (ADS)

    Wang, Ruichen; Xu, Liangpeng; Fan, Chunxiao; Li, Yong

    2018-04-01

    This paper presents an approach to estimating point spread function (PSF) from low resolution (LR) images. Existing techniques usually rely on accurate detection of ending points of the profile normal to edges. In practice however, it is often a great challenge to accurately localize profiles of edges from a LR image, which hence leads to a poor PSF estimation of the lens taking the LR image. For precisely estimating the PSF, this paper proposes firstly estimating a 1-D PSF kernel with straight lines, and then robustly obtaining the 2-D PSF from the 1-D kernel by least squares techniques and random sample consensus. Canny operator is applied to the LR image for obtaining edges and then Hough transform is utilized to extract straight lines of all orientations. Estimating 1-D PSF kernel with straight lines effectively alleviates the influence of the inaccurate edge detection on PSF estimation. The proposed method is investigated on both natural and synthetic images for estimating PSF. Experimental results show that the proposed method outperforms the state-ofthe- art and does not rely on accurate edge detection.

  16. Precision Editing of Large Animal Genomes

    PubMed Central

    Tan, Wenfang (Spring); Carlson, Daniel F.; Walton, Mark W.; Fahrenkrug, Scott C.; Hackett, Perry B.

    2013-01-01

    Transgenic animals are an important source of protein and nutrition for most humans and will play key roles in satisfying the increasing demand for food in an ever-increasing world population. The past decade has experienced a revolution in the development of methods that permit the introduction of specific alterations to complex genomes. This precision will enhance genome-based improvement of farm animals for food production. Precision genetics also will enhance the development of therapeutic biomaterials and models of human disease as resources for the development of advanced patient therapies. PMID:23084873

  17. [Assessment of precision and accuracy of digital surface photogrammetry with the DSP 400 system].

    PubMed

    Krimmel, M; Kluba, S; Dietz, K; Reinert, S

    2005-03-01

    The objective of the present study was to evaluate the precision and accuracy of facial anthropometric measurements obtained through digital 3-D surface photogrammetry with the DSP 400 system in comparison to traditional 2-D photogrammetry. Fifty plaster casts of cleft infants were imaged and 21 standard anthropometric measurements were obtained. For precision assessment the measurements were performed twice in a subsample. Accuracy was determined by comparison of direct measurements and indirect 2-D and 3-D image measurements. Precision of digital surface photogrammetry was almost as good as direct anthropometry and clearly better than 2-D photogrammetry. Measurements derived from 3-D images showed better congruence to direct measurements than from 2-D photos. Digital surface photogrammetry with the DSP 400 system is sufficiently precise and accurate for craniofacial anthropometric examinations.

  18. A Simple yet Accurate Method for the Estimation of the Biovolume of Planktonic Microorganisms.

    PubMed

    Saccà, Alessandro

    2016-01-01

    Determining the biomass of microbial plankton is central to the study of fluxes of energy and materials in aquatic ecosystems. This is typically accomplished by applying proper volume-to-carbon conversion factors to group-specific abundances and biovolumes. A critical step in this approach is the accurate estimation of biovolume from two-dimensional (2D) data such as those available through conventional microscopy techniques or flow-through imaging systems. This paper describes a simple yet accurate method for the assessment of the biovolume of planktonic microorganisms, which works with any image analysis system allowing for the measurement of linear distances and the estimation of the cross sectional area of an object from a 2D digital image. The proposed method is based on Archimedes' principle about the relationship between the volume of a sphere and that of a cylinder in which the sphere is inscribed, plus a coefficient of 'unellipticity' introduced here. Validation and careful evaluation of the method are provided using a variety of approaches. The new method proved to be highly precise with all convex shapes characterised by approximate rotational symmetry, and combining it with an existing method specific for highly concave or branched shapes allows covering the great majority of cases with good reliability. Thanks to its accuracy, consistency, and low resources demand, the new method can conveniently be used in substitution of any extant method designed for convex shapes, and can readily be coupled with automated cell imaging technologies, including state-of-the-art flow-through imaging devices.

  19. A Simple yet Accurate Method for the Estimation of the Biovolume of Planktonic Microorganisms

    PubMed Central

    2016-01-01

    Determining the biomass of microbial plankton is central to the study of fluxes of energy and materials in aquatic ecosystems. This is typically accomplished by applying proper volume-to-carbon conversion factors to group-specific abundances and biovolumes. A critical step in this approach is the accurate estimation of biovolume from two-dimensional (2D) data such as those available through conventional microscopy techniques or flow-through imaging systems. This paper describes a simple yet accurate method for the assessment of the biovolume of planktonic microorganisms, which works with any image analysis system allowing for the measurement of linear distances and the estimation of the cross sectional area of an object from a 2D digital image. The proposed method is based on Archimedes’ principle about the relationship between the volume of a sphere and that of a cylinder in which the sphere is inscribed, plus a coefficient of ‘unellipticity’ introduced here. Validation and careful evaluation of the method are provided using a variety of approaches. The new method proved to be highly precise with all convex shapes characterised by approximate rotational symmetry, and combining it with an existing method specific for highly concave or branched shapes allows covering the great majority of cases with good reliability. Thanks to its accuracy, consistency, and low resources demand, the new method can conveniently be used in substitution of any extant method designed for convex shapes, and can readily be coupled with automated cell imaging technologies, including state-of-the-art flow-through imaging devices. PMID:27195667

  20. Engineering and agronomy aspects of a long-term precision agriculture field experiment

    USDA-ARS?s Scientific Manuscript database

    Much research has been conducted on specific precision agriculture tools and implementation strategies, but little has been reported on long-term evaluation of integrated precision agriculture field experiments. In 2004 our research team developed and initiated a multi-faceted “precision agriculture...

  1. Experimental evaluation of active-member control of precision structures

    NASA Technical Reports Server (NTRS)

    Fanson, James; Blackwood, Gary; Chu, Cheng-Chih

    1989-01-01

    The results of closed loop experiments that use piezoelectric active-members to control the flexible motion of a precision truss structure are described. These experiments are directed toward the development of high-performance structural systems as part of the Control/Structure Interaction (CSI) program at JPL. The focus of CSI activity at JPL is to develop the technology necessary to accurately control both the shape and vibration levels in the precision structures from which proposed large space-based observatories will be built. Structural error budgets for these types of structures will likely be in the sub-micron regime; optical tolerances will be even tighter. In order to achieve system level stability and local positioning at this level, it is generally expected that some form of active control will be required.

  2. Principles of precision medicine in stroke.

    PubMed

    Hinman, Jason D; Rost, Natalia S; Leung, Thomas W; Montaner, Joan; Muir, Keith W; Brown, Scott; Arenillas, Juan F; Feldmann, Edward; Liebeskind, David S

    2017-01-01

    The era of precision medicine has arrived and conveys tremendous potential, particularly for stroke neurology. The diagnosis of stroke, its underlying aetiology, theranostic strategies, recurrence risk and path to recovery are populated by a series of highly individualised questions. Moreover, the phenotypic complexity of a clinical diagnosis of stroke makes a simple genetic risk assessment only partially informative on an individual basis. The guiding principles of precision medicine in stroke underscore the need to identify, value, organise and analyse the multitude of variables obtained from each individual to generate a precise approach to optimise cerebrovascular health. Existing data may be leveraged with novel technologies, informatics and practical clinical paradigms to apply these principles in stroke and realise the promise of precision medicine. Importantly, precision medicine in stroke will only be realised once efforts to collect, value and synthesise the wealth of data collected in clinical trials and routine care starts. Stroke theranostics, the ultimate vision of synchronising tailored therapeutic strategies based on specific diagnostic data, demand cerebrovascular expertise on big data approaches to clinically relevant paradigms. This review considers such challenges and delineates the principles on a roadmap for rational application of precision medicine to stroke and cerebrovascular health. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  3. High-throughput dual-colour precision imaging for brain-wide connectome with cytoarchitectonic landmarks at the cellular level

    PubMed Central

    Gong, Hui; Xu, Dongli; Yuan, Jing; Li, Xiangning; Guo, Congdi; Peng, Jie; Li, Yuxin; Schwarz, Lindsay A.; Li, Anan; Hu, Bihe; Xiong, Benyi; Sun, Qingtao; Zhang, Yalun; Liu, Jiepeng; Zhong, Qiuyuan; Xu, Tonghui; Zeng, Shaoqun; Luo, Qingming

    2016-01-01

    The precise annotation and accurate identification of neural structures are prerequisites for studying mammalian brain function. The orientation of neurons and neural circuits is usually determined by mapping brain images to coarse axial-sampling planar reference atlases. However, individual differences at the cellular level likely lead to position errors and an inability to orient neural projections at single-cell resolution. Here, we present a high-throughput precision imaging method that can acquire a co-localized brain-wide data set of both fluorescent-labelled neurons and counterstained cell bodies at a voxel size of 0.32 × 0.32 × 2.0 μm in 3 days for a single mouse brain. We acquire mouse whole-brain imaging data sets of multiple types of neurons and projections with anatomical annotation at single-neuron resolution. The results show that the simultaneous acquisition of labelled neural structures and cytoarchitecture reference in the same brain greatly facilitates precise tracing of long-range projections and accurate locating of nuclei. PMID:27374071

  4. Highly accurate pulse-per-second timing distribution over optical fibre network using VCSEL side-mode injection

    NASA Astrophysics Data System (ADS)

    Wassin, Shukree; Isoe, George M.; Gamatham, Romeo R. G.; Leitch, Andrew W. R.; Gibbon, Tim B.

    2017-01-01

    Precise and accurate timing signals distributed between a centralized location and several end-users are widely used in both metro-access and speciality networks for Coordinated Universal Time (UTC), GPS satellite systems, banking, very long baseline interferometry and science projects such as SKA radio telescope. Such systems utilize time and frequency technology to ensure phase coherence among data signals distributed across an optical fibre network. For accurate timing requirements, precise time intervals should be measured between successive pulses. In this paper we describe a novel, all optical method for quantifying one-way propagation times and phase perturbations in the fibre length, using pulse-persecond (PPS) signals. The approach utilizes side mode injection of a 1550nm 10Gbps vertical cavity surface emitting laser (VCSEL) at the remote end. A 125 μs one-way time of flight was accurately measured for 25 km G655 fibre. Since the approach is all-optical, it avoids measurement inaccuracies introduced by electro-optical conversion phase delays. Furthermore, the implementation uses cost effective VCSEL technology and suited to a flexible range of network architectures, supporting a number of end-users conducting measurements at the remote end.

  5. Extensively Parameterized Mutation-Selection Models Reliably Capture Site-Specific Selective Constraint.

    PubMed

    Spielman, Stephanie J; Wilke, Claus O

    2016-11-01

    The mutation-selection model of coding sequence evolution has received renewed attention for its use in estimating site-specific amino acid propensities and selection coefficient distributions. Two computationally tractable mutation-selection inference frameworks have been introduced: One framework employs a fixed-effects, highly parameterized maximum likelihood approach, whereas the other employs a random-effects Bayesian Dirichlet Process approach. While both implementations follow the same model, they appear to make distinct predictions about the distribution of selection coefficients. The fixed-effects framework estimates a large proportion of highly deleterious substitutions, whereas the random-effects framework estimates that all substitutions are either nearly neutral or weakly deleterious. It remains unknown, however, how accurately each method infers evolutionary constraints at individual sites. Indeed, selection coefficient distributions pool all site-specific inferences, thereby obscuring a precise assessment of site-specific estimates. Therefore, in this study, we use a simulation-based strategy to determine how accurately each approach recapitulates the selective constraint at individual sites. We find that the fixed-effects approach, despite its extensive parameterization, consistently and accurately estimates site-specific evolutionary constraint. By contrast, the random-effects Bayesian approach systematically underestimates the strength of natural selection, particularly for slowly evolving sites. We also find that, despite the strong differences between their inferred selection coefficient distributions, the fixed- and random-effects approaches yield surprisingly similar inferences of site-specific selective constraint. We conclude that the fixed-effects mutation-selection framework provides the more reliable software platform for model application and future development. © The Author 2016. Published by Oxford University Press on behalf of the

  6. Tau-independent Phase Analysis: A Novel Method for Accurately Determining Phase Shifts.

    PubMed

    Tackenberg, Michael C; Jones, Jeff R; Page, Terry L; Hughey, Jacob J

    2018-06-01

    Estimations of period and phase are essential in circadian biology. While many techniques exist for estimating period, comparatively few methods are available for estimating phase. Current approaches to analyzing phase often vary between studies and are sensitive to coincident changes in period and the stage of the circadian cycle at which the stimulus occurs. Here we propose a new technique, tau-independent phase analysis (TIPA), for quantifying phase shifts in multiple types of circadian time-course data. Through comprehensive simulations, we show that TIPA is both more accurate and more precise than the standard actogram approach. TIPA is computationally simple and therefore will enable accurate and reproducible quantification of phase shifts across multiple subfields of chronobiology.

  7. Daily FOUR score assessment provides accurate prognosis of long-term outcome in out-of-hospital cardiac arrest.

    PubMed

    Weiss, N; Venot, M; Verdonk, F; Chardon, A; Le Guennec, L; Llerena, M C; Raimbourg, Q; Taldir, G; Luque, Y; Fagon, J-Y; Guerot, E; Diehl, J-L

    2015-05-01

    The accurate prediction of outcome after out-of-hospital cardiac arrest (OHCA) is of major importance. The recently described Full Outline of UnResponsiveness (FOUR) is well adapted to mechanically ventilated patients and does not depend on verbal response. To evaluate the ability of FOUR assessed by intensivists to accurately predict outcome in OHCA. We prospectively identified patients admitted for OHCA with a Glasgow Coma Scale below 8. Neurological assessment was performed daily. Outcome was evaluated at 6 months using Glasgow-Pittsburgh Cerebral Performance Categories (GP-CPC). Eighty-five patients were included. At 6 months, 19 patients (22%) had a favorable outcome, GP-CPC 1-2, and 66 (78%) had an unfavorable outcome, GP-CPC 3-5. Compared to both brainstem responses at day 3 and evolution of Glasgow Coma Scale, evolution of FOUR score over the three first days was able to predict unfavorable outcome more precisely. Thus, absence of improvement or worsening from day 1 to day 3 of FOUR had 0.88 (0.79-0.97) specificity, 0.71 (0.66-0.76) sensitivity, 0.94 (0.84-1.00) PPV and 0.54 (0.49-0.59) NPV to predict unfavorable outcome. Similarly, the brainstem response of FOUR score at 0 evaluated at day 3 had 0.94 (0.89-0.99) specificity, 0.60 (0.50-0.70) sensitivity, 0.96 (0.92-1.00) PPV and 0.47 (0.37-0.57) NPV to predict unfavorable outcome. The absence of improvement or worsening from day 1 to day 3 of FOUR evaluated by intensivists provides an accurate prognosis of poor neurological outcome in OHCA. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  8. Precision Therapy for Lung Cancer: Tyrosine Kinase Inhibitors and Beyond.

    PubMed

    Rajan, Arun; Schrump, David S

    2015-01-01

    For patients with advanced cancers there has been a concerted effort to transition from a generic treatment paradigm to one based on tumor-specific biologic, and patient-specific clinical characteristics. This approach, known as precision therapy has been made possible owing to widespread availability and a reduction in the cost of cutting-edge technologies that are used to study the genomic, proteomic, and metabolic attributes of individual tumors. This review traces the evolution of precision therapy for lung cancer from the identification of molecular subsets of the disease to the development and approval of tyrosine kinase, as well as immune checkpoint inhibitors for lung cancer therapy. Challenges of the precision therapy era including the emergence of acquired resistance, identification of untargetable mutations, and the effect on clinical trial design are discussed. We conclude by highlighting newer applications for the concept of precision therapy. Published by Elsevier Inc.

  9. Precise and accurate in situ Pb-Pb dating of apatite, monazite, and sphene by laser ablation multiple-collector ICP-MS

    NASA Astrophysics Data System (ADS)

    Willigers, B. J. A.; Baker, J. A.; Krogstad, E. J.; Peate, D. W.

    2002-03-01

    age data does, however, show a small discrepancy between the LA-MC-ICP-MS and TIMS ages (˜1% younger). High-resolution mass scans of the sphene during ablation clearly showed several small and as yet unidentified isobaric interferences that overlap with the 207Pb peak at the resolution conditions for measurement of isotope ratios. These might account for the age discrepancy between the LA-MC-ICP-MS and TIMS sphene ages. LA-MC-ICP-MS is a rapid, accurate, and precise method for in situ determination of Pb isotope ratios that can be used for geochronological studies in a manner similar to an ion microprobe, albeit currently at a somewhat degraded spatial resolution. Further modifications to the LA-MC-ICP-MS system, such as improved sensitivity, ion transmission, and LA methodology, may lead to this type of instrument becoming the method of choice for many types of in situ Pb isotope dating.

  10. Polyvalent immunoglobulin binding is an obstacle to accurate measurement of specific antibodies with ELISA despite inclusion of blocking agents.

    PubMed

    Loeffler, David A; Klaver, Andrea C

    2017-11-01

    Specific antibody concentrations are frequently measured in serum (and plasma and intravenous immunoglobulin) samples by enzyme-linked immunosorbent assay (ELISA). The standard negative control involves incubation of buffer alone on antigen-coated wells. The immunoreactivity that develops in antigen-coated wells in which diluted serum has been incubated is assumed to represent specific antibody binding. This approach can result in marked overestimation of specific antibody levels, because serum contains specific polyvalent antibodies which bind, primarily with low affinity, to multiple antigens (including those on ELISA plates) despite the use of blocking agents. Non-denaturing purification of serum IgG, followed by assessment of the antigen binding or antigen-binding affinity of this purified IgG, can reduce but not eliminate the problem of polyvalent antibody binding in indirect ELISAs. Alternatively, polyvalent antibody binding can be estimated by incubating a diluted serum sample on wells coated with an irrelevant protein (such as bovine serum albumin or a scrambled peptide sequence) or buffer alone, then subtracting this reactivity from the sample's binding to wells coated with the antigen of interest. Polyvalent binding of immunoglobulins must be accounted for in order to obtain accurate ELISA measurements of serum, plasma, or intravenous immunoglobulin antibodies. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. The GLAS Algorithm Theoretical Basis Document for Precision Orbit Determination (POD)

    NASA Technical Reports Server (NTRS)

    Rim, Hyung Jin; Yoon, S. P.; Schultz, Bob E.

    2013-01-01

    The Geoscience Laser Altimeter System (GLAS) was the sole instrument for NASA's Ice, Cloud and land Elevation Satellite (ICESat) laser altimetry mission. The primary purpose of the ICESat mission was to make ice sheet elevation measurements of the polar regions. Additional goals were to measure the global distribution of clouds and aerosols and to map sea ice, land topography and vegetation. ICESat was the benchmark Earth Observing System (EOS) mission to be used to determine the mass balance of the ice sheets, as well as for providing cloud property information, especially for stratospheric clouds common over polar areas. The GLAS instrument operated from 2003 to 2009 and provided multi-year elevation data needed to determine changes in sea ice freeboard, land topography and vegetation around the globe, in addition to elevation changes of the Greenland and Antarctic ice sheets. This document describes the Precision Orbit Determination (POD) algorithm for the ICESat mission. The problem of determining an accurate ephemeris for an orbiting satellite involves estimating the position and velocity of the satellite from a sequence of observations. The ICESatGLAS elevation measurements must be very accurately geolocated, combining precise orbit information with precision pointing information. The ICESat mission POD requirement states that the position of the instrument should be determined with an accuracy of 5 and 20 cm (1-s) in radial and horizontal components, respectively, to meet the science requirements for determining elevation change.

  12. Accurate LC Peak Boundary Detection for 16 O/ 18 O Labeled LC-MS Data

    PubMed Central

    Cui, Jian; Petritis, Konstantinos; Tegeler, Tony; Petritis, Brianne; Ma, Xuepo; Jin, Yufang; Gao, Shou-Jiang (SJ); Zhang, Jianqiu (Michelle)

    2013-01-01

    In liquid chromatography-mass spectrometry (LC-MS), parts of LC peaks are often corrupted by their co-eluting peptides, which results in increased quantification variance. In this paper, we propose to apply accurate LC peak boundary detection to remove the corrupted part of LC peaks. Accurate LC peak boundary detection is achieved by checking the consistency of intensity patterns within peptide elution time ranges. In addition, we remove peptides with erroneous mass assignment through model fitness check, which compares observed intensity patterns to theoretically constructed ones. The proposed algorithm can significantly improve the accuracy and precision of peptide ratio measurements. PMID:24115998

  13. An Emerging Role for Polystores in Precision Medicine

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

    Begoli, Edmon; Christian, J. Blair; Gadepally, Vijay

    Medical data is organically heterogeneous, and it usually varies significantly in both size and composition. Yet, this data is also a key for the recent and promising field of precision medicine, which focuses on identifying and tailoring appropriate medical treatments for the needs of the individual patients, based on their specific conditions, their medical history, lifestyle, genetic, and other individual factors. As we, and a database community at large, recognize that a “one size does not fit all” solution is required to work with such data, we present in this paper our observations based on our experiences, and the applicationsmore » in the field of precision medicine. Finally, we make the case for the use of polystore architecture; how it applies for precision medicine; we discuss the reference architecture; describe some of its critical components (array database); and discuss the specific types of analysis that directly benefit from this database architecture, and the ways it serves the data.« less

  14. Accurate positioning based on acoustic and optical sensors

    NASA Astrophysics Data System (ADS)

    Cai, Kerong; Deng, Jiahao; Guo, Hualing

    2009-11-01

    Unattended laser target designator (ULTD) was designed to partly take the place of conventional LTDs for accurate positioning and laser marking. Analyzed the precision, accuracy and errors of acoustic sensor array, the requirements of laser generator, and the technology of image analysis and tracking, the major system modules were determined. The target's classification, velocity and position can be measured by sensors, and then coded laser beam will be emitted intelligently to mark the excellent position at the excellent time. The conclusion shows that, ULTD can not only avoid security threats, be deployed massively, and accomplish battle damage assessment (BDA), but also be fit for information-based warfare.

  15. Pink-Beam, Highly-Accurate Compact Water Cooled Slits

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

    Lyndaker, Aaron; Deyhim, Alex; Jayne, Richard

    2007-01-19

    Advanced Design Consulting, Inc. (ADC) has designed accurate compact slits for applications where high precision is required. The system consists of vertical and horizontal slit mechanisms, a vacuum vessel which houses them, water cooling lines with vacuum guards connected to the individual blades, stepper motors with linear encoders, limit (home position) switches and electrical connections including internal wiring for a drain current measurement system. The total slit size is adjustable from 0 to 15 mm both vertically and horizontally. Each of the four blades are individually controlled and motorized. In this paper, a summary of the design and Finite Elementmore » Analysis of the system are presented.« less

  16. Precision wildlife medicine: applications of the human-centred precision medicine revolution to species conservation.

    PubMed

    Whilde, Jenny; Martindale, Mark Q; Duffy, David J

    2017-05-01

    The current species extinction crisis is being exacerbated by an increased rate of emergence of epizootic disease. Human-induced factors including habitat degradation, loss of biodiversity and wildlife population reductions resulting in reduced genetic variation are accelerating disease emergence. Novel, efficient and effective approaches are required to combat these epizootic events. Here, we present the case for the application of human precision medicine approaches to wildlife medicine in order to enhance species conservation efforts. We consider how the precision medicine revolution, coupled with the advances made in genomics, may provide a powerful and feasible approach to identifying and treating wildlife diseases in a targeted, effective and streamlined manner. A number of case studies of threatened species are presented which demonstrate the applicability of precision medicine to wildlife conservation, including sea turtles, amphibians and Tasmanian devils. These examples show how species conservation could be improved by using precision medicine techniques to determine novel treatments and management strategies for the specific medical conditions hampering efforts to restore population levels. Additionally, a precision medicine approach to wildlife health has in turn the potential to provide deeper insights into human health and the possibility of stemming and alleviating the impacts of zoonotic diseases. The integration of the currently emerging Precision Medicine Initiative with the concepts of EcoHealth (aiming for sustainable health of people, animals and ecosystems through transdisciplinary action research) and One Health (recognizing the intimate connection of humans, animal and ecosystem health and addressing a wide range of risks at the animal-human-ecosystem interface through a coordinated, collaborative, interdisciplinary approach) has great potential to deliver a deeper and broader interdisciplinary-based understanding of both wildlife and human

  17. Statistical analysis of an RNA titration series evaluates microarray precision and sensitivity on a whole-array basis

    PubMed Central

    Holloway, Andrew J; Oshlack, Alicia; Diyagama, Dileepa S; Bowtell, David DL; Smyth, Gordon K

    2006-01-01

    Background Concerns are often raised about the accuracy of microarray technologies and the degree of cross-platform agreement, but there are yet no methods which can unambiguously evaluate precision and sensitivity for these technologies on a whole-array basis. Results A methodology is described for evaluating the precision and sensitivity of whole-genome gene expression technologies such as microarrays. The method consists of an easy-to-construct titration series of RNA samples and an associated statistical analysis using non-linear regression. The method evaluates the precision and responsiveness of each microarray platform on a whole-array basis, i.e., using all the probes, without the need to match probes across platforms. An experiment is conducted to assess and compare four widely used microarray platforms. All four platforms are shown to have satisfactory precision but the commercial platforms are superior for resolving differential expression for genes at lower expression levels. The effective precision of the two-color platforms is improved by allowing for probe-specific dye-effects in the statistical model. The methodology is used to compare three data extraction algorithms for the Affymetrix platforms, demonstrating poor performance for the commonly used proprietary algorithm relative to the other algorithms. For probes which can be matched across platforms, the cross-platform variability is decomposed into within-platform and between-platform components, showing that platform disagreement is almost entirely systematic rather than due to measurement variability. Conclusion The results demonstrate good precision and sensitivity for all the platforms, but highlight the need for improved probe annotation. They quantify the extent to which cross-platform measures can be expected to be less accurate than within-platform comparisons for predicting disease progression or outcome. PMID:17118209

  18. Fast and accurate edge orientation processing during object manipulation

    PubMed Central

    Flanagan, J Randall; Johansson, Roland S

    2018-01-01

    Quickly and accurately extracting information about a touched object’s orientation is a critical aspect of dexterous object manipulation. However, the speed and acuity of tactile edge orientation processing with respect to the fingertips as reported in previous perceptual studies appear inadequate in these respects. Here we directly establish the tactile system’s capacity to process edge-orientation information during dexterous manipulation. Participants extracted tactile information about edge orientation very quickly, using it within 200 ms of first touching the object. Participants were also strikingly accurate. With edges spanning the entire fingertip, edge-orientation resolution was better than 3° in our object manipulation task, which is several times better than reported in previous perceptual studies. Performance remained impressive even with edges as short as 2 mm, consistent with our ability to precisely manipulate very small objects. Taken together, our results radically redefine the spatial processing capacity of the tactile system. PMID:29611804

  19. Accurate modeling of the hose instability in plasma wakefield accelerators

    DOE PAGES

    Mehrling, T. J.; Benedetti, C.; Schroeder, C. B.; ...

    2018-05-20

    Hosing is a major challenge for the applicability of plasma wakefield accelerators and its modeling is therefore of fundamental importance to facilitate future stable and compact plasma-based particle accelerators. In this contribution, we present a new model for the evolution of the plasma centroid, which enables the accurate investigation of the hose instability in the nonlinear blowout regime. Lastly, it paves the road for more precise and comprehensive studies of hosing, e.g., with drive and witness beams, which were not possible with previous models.

  20. Accurate modeling of the hose instability in plasma wakefield accelerators

    NASA Astrophysics Data System (ADS)

    Mehrling, T. J.; Benedetti, C.; Schroeder, C. B.; Martinez de la Ossa, A.; Osterhoff, J.; Esarey, E.; Leemans, W. P.

    2018-05-01

    Hosing is a major challenge for the applicability of plasma wakefield accelerators and its modeling is therefore of fundamental importance to facilitate future stable and compact plasma-based particle accelerators. In this contribution, we present a new model for the evolution of the plasma centroid, which enables the accurate investigation of the hose instability in the nonlinear blowout regime. It paves the road for more precise and comprehensive studies of hosing, e.g., with drive and witness beams, which were not possible with previous models.

  1. Accurate modeling of the hose instability in plasma wakefield accelerators

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

    Mehrling, T. J.; Benedetti, C.; Schroeder, C. B.

    Hosing is a major challenge for the applicability of plasma wakefield accelerators and its modeling is therefore of fundamental importance to facilitate future stable and compact plasma-based particle accelerators. In this contribution, we present a new model for the evolution of the plasma centroid, which enables the accurate investigation of the hose instability in the nonlinear blowout regime. Lastly, it paves the road for more precise and comprehensive studies of hosing, e.g., with drive and witness beams, which were not possible with previous models.

  2. An eclipsing-binary distance to the Large Magellanic Cloud accurate to two per cent.

    PubMed

    Pietrzyński, G; Graczyk, D; Gieren, W; Thompson, I B; Pilecki, B; Udalski, A; Soszyński, I; Kozłowski, S; Konorski, P; Suchomska, K; Bono, G; Moroni, P G Prada; Villanova, S; Nardetto, N; Bresolin, F; Kudritzki, R P; Storm, J; Gallenne, A; Smolec, R; Minniti, D; Kubiak, M; Szymański, M K; Poleski, R; Wyrzykowski, L; Ulaczyk, K; Pietrukowicz, P; Górski, M; Karczmarek, P

    2013-03-07

    In the era of precision cosmology, it is essential to determine the Hubble constant to an accuracy of three per cent or better. At present, its uncertainty is dominated by the uncertainty in the distance to the Large Magellanic Cloud (LMC), which, being our second-closest galaxy, serves as the best anchor point for the cosmic distance scale. Observations of eclipsing binaries offer a unique opportunity to measure stellar parameters and distances precisely and accurately. The eclipsing-binary method was previously applied to the LMC, but the accuracy of the distance results was lessened by the need to model the bright, early-type systems used in those studies. Here we report determinations of the distances to eight long-period, late-type eclipsing systems in the LMC, composed of cool, giant stars. For these systems, we can accurately measure both the linear and the angular sizes of their components and avoid the most important problems related to the hot, early-type systems. The LMC distance that we derive from these systems (49.97 ± 0.19 (statistical) ± 1.11 (systematic) kiloparsecs) is accurate to 2.2 per cent and provides a firm base for a 3-per-cent determination of the Hubble constant, with prospects for improvement to 2 per cent in the future.

  3. Correlative imaging across microscopy platforms using the fast and accurate relocation of microscopic experimental regions (FARMER) method

    NASA Astrophysics Data System (ADS)

    Huynh, Toan; Daddysman, Matthew K.; Bao, Ying; Selewa, Alan; Kuznetsov, Andrey; Philipson, Louis H.; Scherer, Norbert F.

    2017-05-01

    Imaging specific regions of interest (ROIs) of nanomaterials or biological samples with different imaging modalities (e.g., light and electron microscopy) or at subsequent time points (e.g., before and after off-microscope procedures) requires relocating the ROIs. Unfortunately, relocation is typically difficult and very time consuming to achieve. Previously developed techniques involve the fabrication of arrays of features, the procedures for which are complex, and the added features can interfere with imaging the ROIs. We report the Fast and Accurate Relocation of Microscopic Experimental Regions (FARMER) method, which only requires determining the coordinates of 3 (or more) conspicuous reference points (REFs) and employs an algorithm based on geometric operators to relocate ROIs in subsequent imaging sessions. The 3 REFs can be quickly added to various regions of a sample using simple tools (e.g., permanent markers or conductive pens) and do not interfere with the ROIs. The coordinates of the REFs and the ROIs are obtained in the first imaging session (on a particular microscope platform) using an accurate and precise encoded motorized stage. In subsequent imaging sessions, the FARMER algorithm finds the new coordinates of the ROIs (on the same or different platforms), using the coordinates of the manually located REFs and the previously recorded coordinates. FARMER is convenient, fast (3-15 min/session, at least 10-fold faster than manual searches), accurate (4.4 μm average error on a microscope with a 100x objective), and precise (almost all errors are <8 μm), even with deliberate rotating and tilting of the sample well beyond normal repositioning accuracy. We demonstrate this versatility by imaging and re-imaging a diverse set of samples and imaging methods: live mammalian cells at different time points; fixed bacterial cells on two microscopes with different imaging modalities; and nanostructures on optical and electron microscopes. FARMER can be readily

  4. Design and control of a macro-micro robot for precise force applications

    NASA Technical Reports Server (NTRS)

    Wang, Yulun; Mangaser, Amante; Laby, Keith; Jordan, Steve; Wilson, Jeff

    1993-01-01

    Creating a robot which can delicately interact with its environment has been the goal of much research. Primarily two difficulties have made this goal hard to attain. The execution of control strategies which enable precise force manipulations are difficult to implement in real time because such algorithms have been too computationally complex for available controllers. Also, a robot mechanism which can quickly and precisely execute a force command is difficult to design. Actuation joints must be sufficiently stiff, frictionless, and lightweight so that desired torques can be accurately applied. This paper describes a robotic system which is capable of delicate manipulations. A modular high-performance multiprocessor control system was designed to provide sufficient compute power for executing advanced control methods. An 8 degree of freedom macro-micro mechanism was constructed to enable accurate tip forces. Control algorithms based on the impedance control method were derived, coded, and load balanced for maximum execution speed on the multiprocessor system. Delicate force tasks such as polishing, finishing, cleaning, and deburring, are the target applications of the robot.

  5. Precision cosmological parameter estimation

    NASA Astrophysics Data System (ADS)

    Fendt, William Ashton, Jr.

    2009-09-01

    Experimental efforts of the last few decades have brought. a golden age to mankind's endeavor to understand tine physical properties of the Universe throughout its history. Recent measurements of the cosmic microwave background (CMB) provide strong confirmation of the standard big bang paradigm, as well as introducing new mysteries, to unexplained by current physical models. In the following decades. even more ambitious scientific endeavours will begin to shed light on the new physics by looking at the detailed structure of the Universe both at very early and recent times. Modern data has allowed us to begins to test inflationary models of the early Universe, and the near future will bring higher precision data and much stronger tests. Cracking the codes hidden in these cosmological observables is a difficult and computationally intensive problem. The challenges will continue to increase as future experiments bring larger and more precise data sets. Because of the complexity of the problem, we are forced to use approximate techniques and make simplifying assumptions to ease the computational workload. While this has been reasonably sufficient until now, hints of the limitations of our techniques have begun to come to light. For example, the likelihood approximation used for analysis of CMB data from the Wilkinson Microwave Anistropy Probe (WMAP) satellite was shown to have short falls, leading to pre-emptive conclusions drawn about current cosmological theories. Also it can he shown that an approximate method used by all current analysis codes to describe the recombination history of the Universe will not be sufficiently accurate for future experiments. With a new CMB satellite scheduled for launch in the coming months, it is vital that we develop techniques to improve the analysis of cosmological data. This work develops a novel technique of both avoiding the use of approximate computational codes as well as allowing the application of new, more precise analysis

  6. Optimization of tissue physical parameters for accurate temperature estimation from finite-element simulation of radiofrequency ablation.

    PubMed

    Subramanian, Swetha; Mast, T Douglas

    2015-10-07

    Computational finite element models are commonly used for the simulation of radiofrequency ablation (RFA) treatments. However, the accuracy of these simulations is limited by the lack of precise knowledge of tissue parameters. In this technical note, an inverse solver based on the unscented Kalman filter (UKF) is proposed to optimize values for specific heat, thermal conductivity, and electrical conductivity resulting in accurately simulated temperature elevations. A total of 15 RFA treatments were performed on ex vivo bovine liver tissue. For each RFA treatment, 15 finite-element simulations were performed using a set of deterministically chosen tissue parameters to estimate the mean and variance of the resulting tissue ablation. The UKF was implemented as an inverse solver to recover the specific heat, thermal conductivity, and electrical conductivity corresponding to the measured area of the ablated tissue region, as determined from gross tissue histology. These tissue parameters were then employed in the finite element model to simulate the position- and time-dependent tissue temperature. Results show good agreement between simulated and measured temperature.

  7. Do We Know Who Will Drop out?: A Review of the Predictors of Dropping out of High School--Precision, Sensitivity, and Specificity

    ERIC Educational Resources Information Center

    Bowers, Alex J.; Sprott, Ryan; Taff, Sherry A.

    2013-01-01

    The purpose of this study is to review the literature on the most accurate indicators of students at risk of dropping out of high school. We used Relative Operating Characteristic (ROC) analysis to compare the sensitivity and specificity of 110 dropout flags across 36 studies. Our results indicate that 1) ROC analysis provides a means to compare…

  8. Improving precise positioning of surgical robotic instruments by a three-side-view presentation system on telesurgery.

    PubMed

    Hori, Kenta; Kuroda, Tomohiro; Oyama, Hiroshi; Ozaki, Yasuhiko; Nakamura, Takehiko; Takahashi, Takashi

    2005-12-01

    For faultless collaboration among the surgeon, surgical staffs, and surgical robots in telesurgery, communication must include environmental information of the remote operating room, such as behavior of robots and staffs, vital information of a patient, named supporting information, in addition to view of surgical field. "Surgical Cockpit System, " which is a telesurgery support system that has been developed by the authors, is mainly focused on supporting information exchange between remote sites. Live video presentation is important technology for Surgical Cockpit System. Visualization method to give precise location/posture of surgical instruments is indispensable for accurate control and faultless operation. In this paper, the authors propose three-side-view presentation method for precise location/posture control of surgical instruments in telesurgery. The experimental results show that the proposed method improved accurate positioning of a telemanipulator.

  9. Precision cancer therapy: profiting from tumor specific defects in the DNA damage tolerance system.

    PubMed

    Buoninfante, Olimpia Alessandra; Pilzecker, Bas; Aslam, Muhammad Assad; Zavrakidis, Ioannis; van der Wiel, Rianne; van de Ven, Marieke; van den Berk, Paul C M; Jacobs, Heinz

    2018-04-10

    DNA damage tolerance (DDT) enables replication to continue in the presence of a damaged template and constitutes a key step in DNA interstrand crosslink repair. In this way DDT minimizes replication stress inflicted by a wide range of endogenous and exogenous agents, and provides a critical first line defense against alkylating and platinating chemotherapeutics. Effective DDT strongly depends on damage-induced, site-specific PCNA-ubiquitination at Lysine (K) 164 by the E2/E3 complex (RAD6/18). A survey of The Cancer Genome Atlas (TCGA) revealed a high frequency of tumors presents RAD6/RAD18 bi-allelic inactivating deletions. For instance, 11% of renal cell carcinoma and 5% of pancreatic tumors have inactivating RAD18 -deletions and 7% of malignant peripheral nerve sheath tumors lack RAD6B . To determine the potential benefit for tumor-specific DDT defects, we followed a genetic approach by establishing unique sets of DDT-proficient Pcna K164 and -defective Pcna K164R lymphoma and breast cancer cell lines. In the absence of exogenous DNA damage, Pcna K164R tumors grew comparably to their Pcna K164 controls in vitro and in vivo . However, DDT-defective lymphomas and breast cancers were compared to their DDT-proficient controls hypersensitive to the chemotherapeutic drug cisplatin (CsPt), both in vitro and in vivo. CsPt strongly inhibited tumor growth and the overall survival of tumor bearing mice greatly improved in the DDT-defective condition. These insights open new therapeutic possibilities for precision cancer medicine with DNA damaging chemotherapeutics and optimize Next-Generation-Sequencing (NGS)-based cancer-diagnostics, -therapeutics, and -prognosis.

  10. Precision cancer therapy: profiting from tumor specific defects in the DNA damage tolerance system

    PubMed Central

    Buoninfante, Olimpia Alessandra; Pilzecker, Bas; Aslam, Muhammad Assad; Zavrakidis, Ioannis; van der Wiel, Rianne; van de Ven, Marieke; van den Berk, Paul C.M.; Jacobs, Heinz

    2018-01-01

    DNA damage tolerance (DDT) enables replication to continue in the presence of a damaged template and constitutes a key step in DNA interstrand crosslink repair. In this way DDT minimizes replication stress inflicted by a wide range of endogenous and exogenous agents, and provides a critical first line defense against alkylating and platinating chemotherapeutics. Effective DDT strongly depends on damage-induced, site-specific PCNA-ubiquitination at Lysine (K) 164 by the E2/E3 complex (RAD6/18). A survey of The Cancer Genome Atlas (TCGA) revealed a high frequency of tumors presents RAD6/RAD18 bi-allelic inactivating deletions. For instance, 11% of renal cell carcinoma and 5% of pancreatic tumors have inactivating RAD18-deletions and 7% of malignant peripheral nerve sheath tumors lack RAD6B. To determine the potential benefit for tumor-specific DDT defects, we followed a genetic approach by establishing unique sets of DDT-proficient PcnaK164 and -defective PcnaK164R lymphoma and breast cancer cell lines. In the absence of exogenous DNA damage, PcnaK164R tumors grew comparably to their PcnaK164 controls in vitro and in vivo. However, DDT-defective lymphomas and breast cancers were compared to their DDT-proficient controls hypersensitive to the chemotherapeutic drug cisplatin (CsPt), both in vitro and in vivo. CsPt strongly inhibited tumor growth and the overall survival of tumor bearing mice greatly improved in the DDT-defective condition. These insights open new therapeutic possibilities for precision cancer medicine with DNA damaging chemotherapeutics and optimize Next-Generation-Sequencing (NGS)-based cancer-diagnostics, -therapeutics, and -prognosis. PMID:29721165

  11. A comparison of average wages with age-specific wages for assessing indirect productivity losses: analytic simplicity versus analytic precision.

    PubMed

    Connolly, Mark P; Tashjian, Cole; Kotsopoulos, Nikolaos; Bhatt, Aomesh; Postma, Maarten J

    2017-07-01

    Numerous approaches are used to estimate indirect productivity losses using various wage estimates applied to poor health in working aged adults. Considering the different wage estimation approaches observed in the published literature, we sought to assess variation in productivity loss estimates when using average wages compared with age-specific wages. Published estimates for average and age-specific wages for combined male/female wages were obtained from the UK Office of National Statistics. A polynomial interpolation was used to convert 5-year age-banded wage data into annual age-specific wages estimates. To compare indirect cost estimates, average wages and age-specific wages were used to project productivity losses at various stages of life based on the human capital approach. Discount rates of 0, 3, and 6 % were applied to projected age-specific and average wage losses. Using average wages was found to overestimate lifetime wages in conditions afflicting those aged 1-27 and 57-67, while underestimating lifetime wages in those aged 27-57. The difference was most significant for children where average wage overestimated wages by 15 % and for 40-year-olds where it underestimated wages by 14 %. Large differences in projecting productivity losses exist when using the average wage applied over a lifetime. Specifically, use of average wages overestimates productivity losses between 8 and 15 % for childhood illnesses. Furthermore, during prime working years, use of average wages will underestimate productivity losses by 14 %. We suggest that to achieve more precise estimates of productivity losses, age-specific wages should become the standard analytic approach.

  12. Accurate MR thermometry by hyperpolarized 129 Xe.

    PubMed

    Zhang, Le; Burant, Alex; McCallister, Andrew; Zhao, Victor; Koshlap, Karl M; Degan, Simone; Antonacci, Michael; Branca, Rosa Tamara

    2017-09-01

    To investigate the temperature dependence of the resonance frequency of lipid-dissolved xenon (LDX) and to assess the accuracy of LDX-based MR thermometry. The chemical shift temperature dependence of water protons, methylene protons, and LDX was measured from samples containing tissues with varying fat contents using a high-resolution NMR spectrometer. LDX results were then used to acquire relative and absolute temperature maps in vivo and the results were compared with PRF-based MR thermometry. The temperature dependence of proton resonance frequency (PRF) is strongly affected by the specific distribution of water and fat. A redistribution of water and fat compartments can reduce the apparent temperature dependence of the water chemical shift from -0.01 ppm/°C to -0.006 ppm, whereas the LDX chemical shift shows a consistent temperature dependence of -0.21 ppm/°C. The use of the methylene protons resonance frequency as internal reference improves the accuracy of LDX-based MR thermometry, but degrades that of PRF-based MR thermometry, as microscopic susceptibility gradients affected lipid and water spins differently. The LDX resonance frequency, with its higher temperature dependence, provides more accurate and precise temperature measurements, both in vitro and in vivo. More importantly, the resonance frequency of nearby methylene protons can be used to extract absolute temperature information. Magn Reson Med 78:1070-1079, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  13. Precision measurement of transition matrix elements via light shift cancellation.

    PubMed

    Herold, C D; Vaidya, V D; Li, X; Rolston, S L; Porto, J V; Safronova, M S

    2012-12-14

    We present a method for accurate determination of atomic transition matrix elements at the 10(-3) level. Measurements of the ac Stark (light) shift around "magic-zero" wavelengths, where the light shift vanishes, provide precise constraints on the matrix elements. We make the first measurement of the 5s - 6p matrix elements in rubidium by measuring the light shift around the 421 and 423 nm zeros through diffraction of a condensate off a sequence of standing wave pulses. In conjunction with existing theoretical and experimental data, we find 0.3235(9)ea(0) and 0.5230(8)ea(0) for the 5s - 6p(1/2) and 5s - 6p(3/2) elements, respectively, an order of magnitude more accurate than the best theoretical values. This technique can provide needed, accurate matrix elements for many atoms, including those used in atomic clocks, tests of fundamental symmetries, and quantum information.

  14. Atomic precision etch using a low-electron temperature plasma

    NASA Astrophysics Data System (ADS)

    Dorf, L.; Wang, J.-C.; Rauf, S.; Zhang, Y.; Agarwal, A.; Kenney, J.; Ramaswamy, K.; Collins, K.

    2016-03-01

    Sub-nm precision is increasingly being required of many critical plasma etching processes in the semiconductor industry. Accurate control over ion energy and ion/radical composition is needed during plasma processing to meet these stringent requirements. Described in this work is a new plasma etch system which has been designed with the requirements of atomic precision plasma processing in mind. In this system, an electron sheet beam parallel to the substrate surface produces a plasma with an order of magnitude lower electron temperature Te (~ 0.3 eV) and ion energy Ei (< 3 eV without applied bias) compared to conventional radio-frequency (RF) plasma technologies. Electron beam plasmas are characterized by higher ion-to-radical fraction compared to RF plasmas, so a separate radical source is used to provide accurate control over relative ion and radical concentrations. Another important element in this plasma system is low frequency RF bias capability which allows control of ion energy in the 2-50 eV range. Presented in this work are the results of etching of a variety of materials and structures performed in this system. In addition to high selectivity and low controllable etch rate, an important requirement of atomic precision etch processes is no (or minimal) damage to the remaining material surface. It has traditionally not been possible to avoid damage in RF plasma processing systems, even during atomic layer etch. The experiments for Si etch in Cl2 based plasmas in the aforementioned etch system show that damage can be minimized if the ion energy is kept below 10 eV. Layer-by-layer etch of Si is also demonstrated in this etch system using electrical and gas pulsing.

  15. StatSTEM: An efficient approach for accurate and precise model-based quantification of atomic resolution electron microscopy images.

    PubMed

    De Backer, A; van den Bos, K H W; Van den Broek, W; Sijbers, J; Van Aert, S

    2016-12-01

    An efficient model-based estimation algorithm is introduced to quantify the atomic column positions and intensities from atomic resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for overlap between neighbouring columns, enabling the analysis of a large field of view. For this algorithm, the accuracy and precision with which measurements for the atomic column positions and scattering cross-sections from annular dark field (ADF) STEM images can be estimated, has been investigated. The highest attainable precision is reached even for low dose images. Furthermore, the advantages of the model-based approach taking into account overlap between neighbouring columns are highlighted. This is done for the estimation of the distance between two neighbouring columns as a function of their distance and for the estimation of the scattering cross-section which is compared to the integrated intensity from a Voronoi cell. To provide end-users this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Big Data’s Role in Precision Public Health

    PubMed Central

    Dolley, Shawn

    2018-01-01

    Precision public health is an emerging practice to more granularly predict and understand public health risks and customize treatments for more specific and homogeneous subpopulations, often using new data, technologies, and methods. Big data is one element that has consistently helped to achieve these goals, through its ability to deliver to practitioners a volume and variety of structured or unstructured data not previously possible. Big data has enabled more widespread and specific research and trials of stratifying and segmenting populations at risk for a variety of health problems. Examples of success using big data are surveyed in surveillance and signal detection, predicting future risk, targeted interventions, and understanding disease. Using novel big data or big data approaches has risks that remain to be resolved. The continued growth in volume and variety of available data, decreased costs of data capture, and emerging computational methods mean big data success will likely be a required pillar of precision public health into the future. This review article aims to identify the precision public health use cases where big data has added value, identify classes of value that big data may bring, and outline the risks inherent in using big data in precision public health efforts. PMID:29594091

  17. Mechanism Design Principle for Optical-Precision, Deployable Instruments

    NASA Technical Reports Server (NTRS)

    Lake, Mark S.; Hachkowski, M. Roman

    2000-01-01

    The present paper is intended to be a guide for the design of 'microdynamically quiet' deployment mechanisms for optical-precision structures, such as deployable telescope mirrors and optical benches. Many of the guidelines included herein come directly from the field of optomechanical engineering, and are neither newly developed guidelines nor are they uniquely applicable to high-precision deployment mechanisms. However, the application of these guidelines to the design of deployment mechanisms is a rather new practice, so efforts are made herein to illustrate the process through the discussion of specific examples. The present paper summarizes a more extensive set of design guidelines for optical-precision mechanisms that are under development.

  18. High-precision relative position and attitude measurement for on-orbit maintenance of spacecraft

    NASA Astrophysics Data System (ADS)

    Zhu, Bing; Chen, Feng; Li, Dongdong; Wang, Ying

    2018-02-01

    In order to realize long-term on-orbit running of satellites, space stations, etc spacecrafts, in addition to the long life design of devices, The life of the spacecraft can also be extended by the on-orbit servicing and maintenance. Therefore, it is necessary to keep precise and detailed maintenance of key components. In this paper, a high-precision relative position and attitude measurement method used in the maintenance of key components is given. This method mainly considers the design of the passive cooperative marker, light-emitting device and high resolution camera in the presence of spatial stray light and noise. By using a series of algorithms, such as background elimination, feature extraction, position and attitude calculation, and so on, the high precision relative pose parameters as the input to the control system between key operation parts and maintenance equipment are obtained. The simulation results show that the algorithm is accurate and effective, satisfying the requirements of the precision operation technique.

  19. Precise Truss Assembly Using Commodity Parts and Low Precision Welding

    NASA Technical Reports Server (NTRS)

    Komendera, Erik; Reishus, Dustin; Dorsey, John T.; Doggett, W. R.; Correll, Nikolaus

    2014-01-01

    Hardware and software design and system integration for an intelligent precision jigging robot (IPJR), which allows high precision assembly using commodity parts and low-precision bonding, is described. Preliminary 2D experiments that are motivated by the problem of assembling space telescope optical benches and very large manipulators on orbit using inexpensive, stock hardware and low-precision welding are also described. An IPJR is a robot that acts as the precise "jigging", holding parts of a local structure assembly site in place, while an external low precision assembly agent cuts and welds members. The prototype presented in this paper allows an assembly agent (for this prototype, a human using only low precision tools), to assemble a 2D truss made of wooden dowels to a precision on the order of millimeters over a span on the order of meters. The analysis of the assembly error and the results of building a square structure and a ring structure are discussed. Options for future work, to extend the IPJR paradigm to building in 3D structures at micron precision are also summarized.

  20. Precise Truss Assembly using Commodity Parts and Low Precision Welding

    NASA Technical Reports Server (NTRS)

    Komendera, Erik; Reishus, Dustin; Dorsey, John T.; Doggett, William R.; Correll, Nikolaus

    2013-01-01

    We describe an Intelligent Precision Jigging Robot (IPJR), which allows high precision assembly of commodity parts with low-precision bonding. We present preliminary experiments in 2D that are motivated by the problem of assembling a space telescope optical bench on orbit using inexpensive, stock hardware and low-precision welding. An IPJR is a robot that acts as the precise "jigging", holding parts of a local assembly site in place while an external low precision assembly agent cuts and welds members. The prototype presented in this paper allows an assembly agent (in this case, a human using only low precision tools), to assemble a 2D truss made of wooden dowels to a precision on the order of millimeters over a span on the order of meters. We report the challenges of designing the IPJR hardware and software, analyze the error in assembly, document the test results over several experiments including a large-scale ring structure, and describe future work to implement the IPJR in 3D and with micron precision.

  1. Rigorous high-precision enclosures of fixed points and their invariant manifolds

    NASA Astrophysics Data System (ADS)

    Wittig, Alexander N.

    The well established concept of Taylor Models is introduced, which offer highly accurate C0 enclosures of functional dependencies, combining high-order polynomial approximation of functions and rigorous estimates of the truncation error, performed using verified arithmetic. The focus of this work is on the application of Taylor Models in algorithms for strongly non-linear dynamical systems. A method is proposed to extend the existing implementation of Taylor Models in COSY INFINITY from double precision coefficients to arbitrary precision coefficients. Great care is taken to maintain the highest efficiency possible by adaptively adjusting the precision of higher order coefficients in the polynomial expansion. High precision operations are based on clever combinations of elementary floating point operations yielding exact values for round-off errors. An experimental high precision interval data type is developed and implemented. Algorithms for the verified computation of intrinsic functions based on the High Precision Interval datatype are developed and described in detail. The application of these operations in the implementation of High Precision Taylor Models is discussed. An application of Taylor Model methods to the verification of fixed points is presented by verifying the existence of a period 15 fixed point in a near standard Henon map. Verification is performed using different verified methods such as double precision Taylor Models, High Precision intervals and High Precision Taylor Models. Results and performance of each method are compared. An automated rigorous fixed point finder is implemented, allowing the fully automated search for all fixed points of a function within a given domain. It returns a list of verified enclosures of each fixed point, optionally verifying uniqueness within these enclosures. An application of the fixed point finder to the rigorous analysis of beam transfer maps in accelerator physics is presented. Previous work done by

  2. Precision Spectroscopy of Atomic Hydrogen

    NASA Astrophysics Data System (ADS)

    Hänsch, Theodor W.

    1994-08-01

    The simple hydrogen atom permits unique confrontations between spectroscopic experiment and fundamental theory. The experimental resolution and measurement accuracy continue to improve exponentially. Recent advances include a new measurement of the Lamb shift of the 1S ground state which provides now the most stringent test of QED for an atom and reveals unexpectedly large two-loop binding corrections. The H-D isotope shift of the extremely narrow 1S-2S two-photon resonance is yielding a new value for the structure radius of the deuteron, in agreement with nuclear theory. The Rydberg constant as determined within 3 parts in 1011 by two independent groups has become the most accurately known of any fundamental constant. Advances in the art of absolute optical frequency measurements will permit still more precise experiments in the near future.

  3. Accurate frequency and time dissemination in the optical domain

    NASA Astrophysics Data System (ADS)

    Khabarova, K. Yu; Kalganova, E. S.; Kolachevsky, N. N.

    2018-02-01

    The development of the optical frequency comb technique has enabled a wide use of atomic optical clocks by allowing frequency conversion from the optical to the radio frequency range. Today, the fractional instability of such clocks has reached the record eighteen-digit level, two orders of magnitude better than for cesium fountains representing the primary frequency standard. This is paralleled by the development of techniques for transferring accurate time and optical frequency signals, including fiber links. With this technology, the fractional instability of transferred frequency can be lowered to below 10‑18 with an averaging time of 1000 s for a 1000 km optical link. At a distance of 500 km, a time signal uncertainty of 250 ps has been achieved. Optical links allow comparing optical clocks and creating a synchronized time and frequency standard network at a new level of precision. Prospects for solving new problems arise, including the determination of the gravitational potential, the measurement of the continental Sagnac effect, and precise tests of fundamental theories.

  4. Subject-specific bone attenuation correction for brain PET/MR: can ZTE-MRI substitute CT scan accurately?

    PubMed

    Khalifé, Maya; Fernandez, Brice; Jaubert, Olivier; Soussan, Michael; Brulon, Vincent; Buvat, Irène; Comtat, Claude

    2017-09-21

    In brain PET/MR applications, accurate attenuation maps are required for accurate PET image quantification. An implemented attenuation correction (AC) method for brain imaging is the single-atlas approach that estimates an AC map from an averaged CT template. As an alternative, we propose to use a zero echo time (ZTE) pulse sequence to segment bone, air and soft tissue. A linear relationship between histogram normalized ZTE intensity and measured CT density in Hounsfield units ([Formula: see text]) in bone has been established thanks to a CT-MR database of 16 patients. Continuous AC maps were computed based on the segmented ZTE by setting a fixed linear attenuation coefficient (LAC) to air and soft tissue and by using the linear relationship to generate continuous μ values for the bone. Additionally, for the purpose of comparison, four other AC maps were generated: a ZTE derived AC map with a fixed LAC for the bone, an AC map based on the single-atlas approach as provided by the PET/MR manufacturer, a soft-tissue only AC map and, finally, the CT derived attenuation map used as the gold standard (CTAC). All these AC maps were used with different levels of smoothing for PET image reconstruction with and without time-of-flight (TOF). The subject-specific AC map generated by combining ZTE-based segmentation and linear scaling of the normalized ZTE signal into [Formula: see text] was found to be a good substitute for the measured CTAC map in brain PET/MR when used with a Gaussian smoothing kernel of [Formula: see text] corresponding to the PET scanner intrinsic resolution. As expected TOF reduces AC error regardless of the AC method. The continuous ZTE-AC performed better than the other alternative MR derived AC methods, reducing the quantification error between the MRAC corrected PET image and the reference CTAC corrected PET image.

  5. Subject-specific bone attenuation correction for brain PET/MR: can ZTE-MRI substitute CT scan accurately?

    NASA Astrophysics Data System (ADS)

    Khalifé, Maya; Fernandez, Brice; Jaubert, Olivier; Soussan, Michael; Brulon, Vincent; Buvat, Irène; Comtat, Claude

    2017-10-01

    In brain PET/MR applications, accurate attenuation maps are required for accurate PET image quantification. An implemented attenuation correction (AC) method for brain imaging is the single-atlas approach that estimates an AC map from an averaged CT template. As an alternative, we propose to use a zero echo time (ZTE) pulse sequence to segment bone, air and soft tissue. A linear relationship between histogram normalized ZTE intensity and measured CT density in Hounsfield units (HU ) in bone has been established thanks to a CT-MR database of 16 patients. Continuous AC maps were computed based on the segmented ZTE by setting a fixed linear attenuation coefficient (LAC) to air and soft tissue and by using the linear relationship to generate continuous μ values for the bone. Additionally, for the purpose of comparison, four other AC maps were generated: a ZTE derived AC map with a fixed LAC for the bone, an AC map based on the single-atlas approach as provided by the PET/MR manufacturer, a soft-tissue only AC map and, finally, the CT derived attenuation map used as the gold standard (CTAC). All these AC maps were used with different levels of smoothing for PET image reconstruction with and without time-of-flight (TOF). The subject-specific AC map generated by combining ZTE-based segmentation and linear scaling of the normalized ZTE signal into HU was found to be a good substitute for the measured CTAC map in brain PET/MR when used with a Gaussian smoothing kernel of 4~mm corresponding to the PET scanner intrinsic resolution. As expected TOF reduces AC error regardless of the AC method. The continuous ZTE-AC performed better than the other alternative MR derived AC methods, reducing the quantification error between the MRAC corrected PET image and the reference CTAC corrected PET image.

  6. Digital PCR Modeling for Maximal Sensitivity, Dynamic Range and Measurement Precision

    PubMed Central

    Majumdar, Nivedita; Wessel, Thomas; Marks, Jeffrey

    2015-01-01

    The great promise of digital PCR is the potential for unparalleled precision enabling accurate measurements for genetic quantification. A challenge associated with digital PCR experiments, when testing unknown samples, is to perform experiments at dilutions allowing the detection of one or more targets of interest at a desired level of precision. While theory states that optimal precision (Po) is achieved by targeting ~1.59 mean copies per partition (λ), and that dynamic range (R) includes the space spanning one positive (λL) to one negative (λU) result from the total number of partitions (n), these results are tempered for the practitioner seeking to construct digital PCR experiments in the laboratory. A mathematical framework is presented elucidating the relationships between precision, dynamic range, number of partitions, interrogated volume, and sensitivity in digital PCR. The impact that false reaction calls and volumetric variation have on sensitivity and precision is next considered. The resultant effects on sensitivity and precision are established via Monte Carlo simulations reflecting the real-world likelihood of encountering such scenarios in the laboratory. The simulations provide insight to the practitioner on how to adapt experimental loading concentrations to counteract any one of these conditions. The framework is augmented with a method of extending the dynamic range of digital PCR, with and without increasing n, via the use of dilutions. An example experiment demonstrating the capabilities of the framework is presented enabling detection across 3.33 logs of starting copy concentration. PMID:25806524

  7. Specificity of Postural Sway to the Demands of a Precision Task at Sea

    ERIC Educational Resources Information Center

    Chen, Fu-Chen; Stoffregen, Thomas A.

    2012-01-01

    Mariners actively adjust their body orientation in response to ship motion. On a ship at sea, we evaluated relations between standing postural activity and the performance of a precision aiming task. Standing participants (experienced mariners) maintained the beam from a handheld laser on a target. Targets were large or small, thereby varying the…

  8. The double-edged sword of high-precision U-Pb geochronology or be careful what you wish for. (Invited)

    NASA Astrophysics Data System (ADS)

    Bowring, S. A.

    2010-12-01

    Over the past two decades, U-Pb geochronology by ID-TIMS has been refined to achieve internal (analytical) uncertainties on a single grain analysis of ± ~ 0.1-0.2%, and 0.05% or better on weighted mean dates. This level of precision enables unprecedented evaluation of the rates and durations of geological processes, from magma chamber evolution to mass extinctions and recoveries. The increased precision, however, exposes complexity in magmatic/volcanic systems and highlights the importance of corrections related to disequilibrium partitioning of intermediate daughter products, and raises questions as to how best to interpret the complex spectrum of dates characteristic of many volcanic rocks. In addition, the increased precision requires renewed emphasis on the accuracy of U decay constants, the isotopic composition of U, the calibration of isotopic tracers, and the accurate propagation of uncertainties It is now commonplace in the high precision dating of volcanic ash-beds to analyze 5-20 single grains of zircon in an attempt to resolve the eruption/depositional age. Data sets with dispersion far in excess of analytical uncertainties are interpreted to reflect Pb-loss, inheritance, and protracted crystallization, often supported with zircon chemistry. In most cases, a weighted mean of the youngest reproducible dates is interpreted as the time of eruption/deposition. Crystallization histories of silicic magmatic systems recovered from plutonic rocks may also be protracted, though may not be directly applicable to silicic eruptions; each sample must be evaluated independently. A key to robust interpretations is the integration high-spatial resolution zircon trace element geochemistry with high-precision ID-TIMS analyses. The EARTHTIME initiative has focused on many of these issues, and the larger subject of constructing a timeline for earth history using both U-Pb and Ar-Ar chronometers. Despite continuing improvements in both, comparing dates for the same rock

  9. Highly Accurate and Precise Infrared Transition Frequencies of the H_3^+ Cation

    NASA Astrophysics Data System (ADS)

    Perry, Adam J.; Markus, Charles R.; Hodges, James N.; Kocheril, G. Stephen; McCall, Benjamin J.

    2016-06-01

    Calculation of ab initio potential energy surfaces for molecules to high accuracy is only manageable for a handful of molecular systems. Among them is the simplest polyatomic molecule, the H_3^+ cation. In order to achieve a high degree of accuracy (<1 wn) corrections must be made to the to the traditional Born-Oppenheimer approximation that take into account not only adiabatic and non-adiabatic couplings, but quantum electrodynamic corrections as well. For the lowest rovibrational levels the agreement between theory and experiment is approaching 0.001 wn, whereas the agreement is on the order of 0.01 - 0.1 wn for higher levels which are closely rivaling the uncertainties on the experimental data. As method development for calculating these various corrections progresses it becomes necessary for the uncertainties on the experimental data to be improved in order to properly benchmark the calculations. Previously we have measured 20 rovibrational transitions of H_3^+ with MHz-level precision, all of which have arisen from low lying rotational levels. Here we present new measurements of rovibrational transitions arising from higher rotational and vibrational levels. These transitions not only allow for probing higher energies on the potential energy surface, but through the use of combination differences, will ultimately lead to prediction of the "forbidden" rotational transitions with MHz-level accuracy. L.G. Diniz, J.R. Mohallem, A. Alijah, M. Pavanello, L. Adamowicz, O.L. Polyansky, J. Tennyson Phys. Rev. A (2013), 88, 032506 O.L. Polyansky, A. Alijah, N.F. Zobov, I.I. Mizus, R.I. Ovsyannikov, J. Tennyson, L. Lodi, T. Szidarovszky, A.G. Császár Phil. Trans. R. Soc. A (2012), 370, 5014 J.N. Hodges, A.J. Perry, P.A. Jenkins II, B.M. Siller, B.J. McCall J. Chem. Phys. (2013), 139, 164201 A.J. Perry, J.N. Hodges, C.R. Markus, G.S. Kocheril, B.J. McCall J. Molec. Spectrosc. (2015), 317, 71-73.

  10. Polynomial Fitting of DT-MRI Fiber Tracts Allows Accurate Estimation of Muscle Architectural Parameters

    PubMed Central

    Damon, Bruce M.; Heemskerk, Anneriet M.; Ding, Zhaohua

    2012-01-01

    Fiber curvature is a functionally significant muscle structural property, but its estimation from diffusion-tensor MRI fiber tracking data may be confounded by noise. The purpose of this study was to investigate the use of polynomial fitting of fiber tracts for improving the accuracy and precision of fiber curvature (κ) measurements. Simulated image datasets were created in order to provide data with known values for κ and pennation angle (θ). Simulations were designed to test the effects of increasing inherent fiber curvature (3.8, 7.9, 11.8, and 15.3 m−1), signal-to-noise ratio (50, 75, 100, and 150), and voxel geometry (13.8 and 27.0 mm3 voxel volume with isotropic resolution; 13.5 mm3 volume with an aspect ratio of 4.0) on κ and θ measurements. In the originally reconstructed tracts, θ was estimated accurately under most curvature and all imaging conditions studied; however, the estimates of κ were imprecise and inaccurate. Fitting the tracts to 2nd order polynomial functions provided accurate and precise estimates of κ for all conditions except very high curvature (κ=15.3 m−1), while preserving the accuracy of the θ estimates. Similarly, polynomial fitting of in vivo fiber tracking data reduced the κ values of fitted tracts from those of unfitted tracts and did not change the θ values. Polynomial fitting of fiber tracts allows accurate estimation of physiologically reasonable values of κ, while preserving the accuracy of θ estimation. PMID:22503094

  11. Correlation of the turbo-MP RIA with ImmunoCAP FEIA for determination of food allergen-specific immunoglobulin E.

    PubMed

    Kontis, Kris J; Valcour, Andre; Patel, Ashok; Chen, Andy; Wang, Jan; Chow, Julia; Nayak, Narayan

    2006-01-01

    It has been reported that in vitro measurement of food-specific IgE can be used to accurately predict food allergy and reduce the risk associated with double-blinded placebo-controlled food challenges (DBPCFC). Our objective was to assess the performance characteristics of the Hycor Turbo-MP quantitative radioimmunoassay for food-specific IgE and to determine this method's comparability to another assay, the Pharmacia ImmunoCAP fluorescence enzyme immunoassay (FEIA). The dynamic range of the Turbo-MP assay is 0.05 to 100 IU/ml, compared to 0.35 to 100 IU/ml for the FEIA. Performance characteristics of the Turbo-MP assay (ie, reproducibility of the calibration curve, within-run precision, total precision, parallelism, and linearity) were determined using samples from the Hycor serum bank. The precision (CV) of IgE calibrator replicates was <10%. The total precision (CV) of the Turbo-MP assay ranged from 8.8% to 18.4% for specific IgE concentrations between 0.28 to 31.4 IU/ml. Testing of serial dilutions of sera with IgE specificities for egg white, cow's milk, codfish, wheat, peanut, and soybean showed that the assay is linear over the entire dynamic range. Serial dilution data (slopes of 1.01 to 1.10) showed parallelism to serial dilutions of the IgE calibrator (slope of 0.96). The Turbo-MP and FEIA methods were both used for quantitative assays of food-specific IgE in 457 serum samples obtained from a clinical reference laboratory. Comparison of specific IgE results by the Turbo-MP and FEIA methods for 6 major food allergens exhibited a slope of 0.99 (0.92 to 1.03) with a correlation coefficient of 0.81.

  12. A Road Map for Precision Medicine in the Epilepsies

    PubMed Central

    2015-01-01

    Summary Technological advances have paved the way for accelerated genomic discovery and are bringing precision medicine clearly into view. Epilepsy research in particular is well-suited to serve as a model for the development and deployment of targeted therapeutics in precision medicine because of the rapidly expanding genetic knowledge base in epilepsy, the availability of good in vitro and in vivo model systems to efficiently study the biological consequences of genetic mutations, the ability to turn these models into effective drug screening platforms, and the establishment of collaborative research groups. Moving forward, it is critical that we strengthen these collaborations, particularly through integrated research platforms to provide robust analyses both for accurate personal genome analysis and gene and drug discovery. Similarly, the implementation of clinical trial networks will allow the expansion of patient sample populations with genetically defined epilepsy so that drug discovery can be translated into clinical practice. PMID:26416172

  13. Retinotopic memory is more precise than spatiotopic memory.

    PubMed

    Golomb, Julie D; Kanwisher, Nancy

    2012-01-31

    Successful visually guided behavior requires information about spatiotopic (i.e., world-centered) locations, but how accurately is this information actually derived from initial retinotopic (i.e., eye-centered) visual input? We conducted a spatial working memory task in which subjects remembered a cued location in spatiotopic or retinotopic coordinates while making guided eye movements during the memory delay. Surprisingly, after a saccade, subjects were significantly more accurate and precise at reporting retinotopic locations than spatiotopic locations. This difference grew with each eye movement, such that spatiotopic memory continued to deteriorate, whereas retinotopic memory did not accumulate error. The loss in spatiotopic fidelity is therefore not a generic consequence of eye movements, but a direct result of converting visual information from native retinotopic coordinates. Thus, despite our conscious experience of an effortlessly stable spatiotopic world and our lifetime of practice with spatiotopic tasks, memory is actually more reliable in raw retinotopic coordinates than in ecologically relevant spatiotopic coordinates.

  14. Accuracy and Precision in Measurements of Biomass Oxidative Ratio and Carbon Oxidation State

    NASA Astrophysics Data System (ADS)

    Gallagher, M. E.; Masiello, C. A.; Randerson, J. T.; Chadwick, O. A.; Robertson, G. P.

    2007-12-01

    Ecosystem oxidative ratio (OR) is a critical parameter in the apportionment of anthropogenic CO2 between the terrestrial biosphere and ocean carbon reservoirs. OR is the ratio of O2 to CO2 in gas exchange fluxes between the terrestrial biosphere and atmosphere. Ecosystem OR is linearly related to biomass carbon oxidation state (Cox), a fundamental property of the earth system describing the bonding environment of carbon in molecules. Cox can range from -4 to +4 (CH4 to CO2). Variations in both Cox and OR are driven by photosynthesis, respiration, and decomposition. We are developing several techniques to accurately measure variations in ecosystem Cox and OR; these include elemental analysis, bomb calorimetry, and 13C nuclear magnetic resonance spectroscopy. A previous study, comparing the accuracy and precision of elemental analysis versus bomb calorimetry for pure chemicals, showed that elemental analysis-based measurements are more accurate, while calorimetry- based measurements yield more precise data. However, the limited biochemical range of natural samples makes it possible that calorimetry may ultimately prove most accurate, as well as most cost-effective. Here we examine more closely the accuracy of Cox and OR values generated by calorimetry on a large set of natural biomass samples collected from the Kellogg Biological Station-Long Term Ecological Research (KBS-LTER) site in Michigan.

  15. Accurate Thermal Stresses for Beams: Normal Stress

    NASA Technical Reports Server (NTRS)

    Johnson, Theodore F.; Pilkey, Walter D.

    2002-01-01

    Formulations for a general theory of thermoelasticity to generate accurate thermal stresses for structural members of aeronautical vehicles were developed in 1954 by Boley. The formulation also provides three normal stresses and a shear stress along the entire length of the beam. The Poisson effect of the lateral and transverse normal stresses on a thermally loaded beam is taken into account in this theory by employing an Airy stress function. The Airy stress function enables the reduction of the three-dimensional thermal stress problem to a two-dimensional one. Numerical results from the general theory of thermoelasticity are compared to those obtained from strength of materials. It is concluded that the theory of thermoelasticity for prismatic beams proposed in this paper can be used instead of strength of materials when precise stress results are desired.

  16. Accurate Thermal Stresses for Beams: Normal Stress

    NASA Technical Reports Server (NTRS)

    Johnson, Theodore F.; Pilkey, Walter D.

    2003-01-01

    Formulations for a general theory of thermoelasticity to generate accurate thermal stresses for structural members of aeronautical vehicles were developed in 1954 by Boley. The formulation also provides three normal stresses and a shear stress along the entire length of the beam. The Poisson effect of the lateral and transverse normal stresses on a thermally loaded beam is taken into account in this theory by employing an Airy stress function. The Airy stress function enables the reduction of the three-dimensional thermal stress problem to a two-dimensional one. Numerical results from the general theory of thermoelasticity are compared to those obtained from strength of materials. It is concluded that the theory of thermoelasticity for prismatic beams proposed in this paper can be used instead of strength of materials when precise stress results are desired.

  17. The cancer precision medicine knowledge base for structured clinical-grade mutations and interpretations.

    PubMed

    Huang, Linda; Fernandes, Helen; Zia, Hamid; Tavassoli, Peyman; Rennert, Hanna; Pisapia, David; Imielinski, Marcin; Sboner, Andrea; Rubin, Mark A; Kluk, Michael; Elemento, Olivier

    2017-05-01

    This paper describes the Precision Medicine Knowledge Base (PMKB; https://pmkb.weill.cornell.edu ), an interactive online application for collaborative editing, maintenance, and sharing of structured clinical-grade cancer mutation interpretations. PMKB was built using the Ruby on Rails Web application framework. Leveraging existing standards such as the Human Genome Variation Society variant description format, we implemented a data model that links variants to tumor-specific and tissue-specific interpretations. Key features of PMKB include support for all major variant types, standardized authentication, distinct user roles including high-level approvers, and detailed activity history. A REpresentational State Transfer (REST) application-programming interface (API) was implemented to query the PMKB programmatically. At the time of writing, PMKB contains 457 variant descriptions with 281 clinical-grade interpretations. The EGFR, BRAF, KRAS, and KIT genes are associated with the largest numbers of interpretable variants. PMKB's interpretations have been used in over 1500 AmpliSeq tests and 750 whole-exome sequencing tests. The interpretations are accessed either directly via the Web interface or programmatically via the existing API. An accurate and up-to-date knowledge base of genomic alterations of clinical significance is critical to the success of precision medicine programs. The open-access, programmatically accessible PMKB represents an important attempt at creating such a resource in the field of oncology. The PMKB was designed to help collect and maintain clinical-grade mutation interpretations and facilitate reporting for clinical cancer genomic testing. The PMKB was also designed to enable the creation of clinical cancer genomics automated reporting pipelines via an API. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association.

  18. The cancer precision medicine knowledge base for structured clinical-grade mutations and interpretations

    PubMed Central

    Huang, Linda; Fernandes, Helen; Zia, Hamid; Tavassoli, Peyman; Rennert, Hanna; Pisapia, David; Imielinski, Marcin; Sboner, Andrea; Rubin, Mark A; Kluk, Michael

    2017-01-01

    Objective: This paper describes the Precision Medicine Knowledge Base (PMKB; https://pmkb.weill.cornell.edu), an interactive online application for collaborative editing, maintenance, and sharing of structured clinical-grade cancer mutation interpretations. Materials and Methods: PMKB was built using the Ruby on Rails Web application framework. Leveraging existing standards such as the Human Genome Variation Society variant description format, we implemented a data model that links variants to tumor-specific and tissue-specific interpretations. Key features of PMKB include support for all major variant types, standardized authentication, distinct user roles including high-level approvers, and detailed activity history. A REpresentational State Transfer (REST) application-programming interface (API) was implemented to query the PMKB programmatically. Results: At the time of writing, PMKB contains 457 variant descriptions with 281 clinical-grade interpretations. The EGFR, BRAF, KRAS, and KIT genes are associated with the largest numbers of interpretable variants. PMKB’s interpretations have been used in over 1500 AmpliSeq tests and 750 whole-exome sequencing tests. The interpretations are accessed either directly via the Web interface or programmatically via the existing API. Discussion: An accurate and up-to-date knowledge base of genomic alterations of clinical significance is critical to the success of precision medicine programs. The open-access, programmatically accessible PMKB represents an important attempt at creating such a resource in the field of oncology. Conclusion: The PMKB was designed to help collect and maintain clinical-grade mutation interpretations and facilitate reporting for clinical cancer genomic testing. The PMKB was also designed to enable the creation of clinical cancer genomics automated reporting pipelines via an API. PMID:27789569

  19. Precision diagnostics: moving towards protein biomarker signatures of clinical utility in cancer.

    PubMed

    Borrebaeck, Carl A K

    2017-03-01

    Interest in precision diagnostics has been fuelled by the concept that early detection of cancer would benefit patients; that is, if detected early, more tumours should be resectable and treatment more efficacious. Serum contains massive amounts of potentially diagnostic information, and affinity proteomics has risen as an accurate approach to decipher this, to generate actionable information that should result in more precise and evidence-based options to manage cancer. To achieve this, we need to move from single to multiplex biomarkers, a so-called signature, that can provide significantly increased diagnostic accuracy. This Opinion article focuses on the progress being made in identifying protein biomarker signatures of clinical utility, using blood-based proteomics.

  20. FASTSIM2: a second-order accurate frictional rolling contact algorithm

    NASA Astrophysics Data System (ADS)

    Vollebregt, E. A. H.; Wilders, P.

    2011-01-01

    In this paper we consider the frictional (tangential) steady rolling contact problem. We confine ourselves to the simplified theory, instead of using full elastostatic theory, in order to be able to compute results fast, as needed for on-line application in vehicle system dynamics simulation packages. The FASTSIM algorithm is the leading technology in this field and is employed in all dominant railway vehicle system dynamics packages (VSD) in the world. The main contribution of this paper is a new version "FASTSIM2" of the FASTSIM algorithm, which is second-order accurate. This is relevant for VSD, because with the new algorithm 16 times less grid points are required for sufficiently accurate computations of the contact forces. The approach is based on new insights in the characteristics of the rolling contact problem when using the simplified theory, and on taking precise care of the contact conditions in the numerical integration scheme employed.

  1. Accuracy of complete-arch dental impressions: a new method of measuring trueness and precision.

    PubMed

    Ender, Andreas; Mehl, Albert

    2013-02-01

    A new approach to both 3-dimensional (3D) trueness and precision is necessary to assess the accuracy of intraoral digital impressions and compare them to conventionally acquired impressions. The purpose of this in vitro study was to evaluate whether a new reference scanner is capable of measuring conventional and digital intraoral complete-arch impressions for 3D accuracy. A steel reference dentate model was fabricated and measured with a reference scanner (digital reference model). Conventional impressions were made from the reference model, poured with Type IV dental stone, scanned with the reference scanner, and exported as digital models. Additionally, digital impressions of the reference model were made and the digital models were exported. Precision was measured by superimposing the digital models within each group. Superimposing the digital models on the digital reference model assessed the trueness of each impression method. Statistical significance was assessed with an independent sample t test (α=.05). The reference scanner delivered high accuracy over the entire dental arch with a precision of 1.6 ±0.6 µm and a trueness of 5.3 ±1.1 µm. Conventional impressions showed significantly higher precision (12.5 ±2.5 µm) and trueness values (20.4 ±2.2 µm) with small deviations in the second molar region (P<.001). Digital impressions were significantly less accurate with a precision of 32.4 ±9.6 µm and a trueness of 58.6 ±15.8µm (P<.001). More systematic deviations of the digital models were visible across the entire dental arch. The new reference scanner is capable of measuring the precision and trueness of both digital and conventional complete-arch impressions. The digital impression is less accurate and shows a different pattern of deviation than the conventional impression. Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  2. Accurate computation of gravitational field of a tesseroid

    NASA Astrophysics Data System (ADS)

    Fukushima, Toshio

    2018-02-01

    We developed an accurate method to compute the gravitational field of a tesseroid. The method numerically integrates a surface integral representation of the gravitational potential of the tesseroid by conditionally splitting its line integration intervals and by using the double exponential quadrature rule. Then, it evaluates the gravitational acceleration vector and the gravity gradient tensor by numerically differentiating the numerically integrated potential. The numerical differentiation is conducted by appropriately switching the central and the single-sided second-order difference formulas with a suitable choice of the test argument displacement. If necessary, the new method is extended to the case of a general tesseroid with the variable density profile, the variable surface height functions, and/or the variable intervals in longitude or in latitude. The new method is capable of computing the gravitational field of the tesseroid independently on the location of the evaluation point, namely whether outside, near the surface of, on the surface of, or inside the tesseroid. The achievable precision is 14-15 digits for the potential, 9-11 digits for the acceleration vector, and 6-8 digits for the gradient tensor in the double precision environment. The correct digits are roughly doubled if employing the quadruple precision computation. The new method provides a reliable procedure to compute the topographic gravitational field, especially that near, on, and below the surface. Also, it could potentially serve as a sure reference to complement and elaborate the existing approaches using the Gauss-Legendre quadrature or other standard methods of numerical integration.

  3. eRAM: encyclopedia of rare disease annotations for precision medicine.

    PubMed

    Jia, Jinmeng; An, Zhongxin; Ming, Yue; Guo, Yongli; Li, Wei; Liang, Yunxiang; Guo, Dongming; Li, Xin; Tai, Jun; Chen, Geng; Jin, Yaqiong; Liu, Zhimei; Ni, Xin; Shi, Tieliu

    2018-01-04

    Rare diseases affect over a hundred million people worldwide, most of these patients are not accurately diagnosed and effectively treated. The limited knowledge of rare diseases forms the biggest obstacle for improving their treatment. Detailed clinical phenotyping is considered as a keystone of deciphering genes and realizing the precision medicine for rare diseases. Here, we preset a standardized system for various types of rare diseases, called encyclopedia of Rare disease Annotations for Precision Medicine (eRAM). eRAM was built by text-mining nearly 10 million scientific publications and electronic medical records, and integrating various data in existing recognized databases (such as Unified Medical Language System (UMLS), Human Phenotype Ontology, Orphanet, OMIM, GWAS). eRAM systematically incorporates currently available data on clinical manifestations and molecular mechanisms of rare diseases and uncovers many novel associations among diseases. eRAM provides enriched annotations for 15 942 rare diseases, yielding 6147 human disease related phenotype terms, 31 661 mammalians phenotype terms, 10,202 symptoms from UMLS, 18 815 genes and 92 580 genotypes. eRAM can not only provide information about rare disease mechanism but also facilitate clinicians to make accurate diagnostic and therapeutic decisions towards rare diseases. eRAM can be freely accessed at http://www.unimd.org/eram/. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  4. High precision analytical description of the allowed β spectrum shape

    NASA Astrophysics Data System (ADS)

    Hayen, Leendert; Severijns, Nathal; Bodek, Kazimierz; Rozpedzik, Dagmara; Mougeot, Xavier

    2018-01-01

    A fully analytical description of the allowed β spectrum shape is given in view of ongoing and planned measurements. Its study forms an invaluable tool in the search for physics beyond the standard electroweak model and the weak magnetism recoil term. Contributions stemming from finite size corrections, mass effects, and radiative corrections are reviewed. Particular focus is placed on atomic and chemical effects, where the existing description is extended and analytically provided. The effects of QCD-induced recoil terms are discussed, and cross-checks were performed for different theoretical formalisms. Special attention was given to a comparison of the treatment of nuclear structure effects in different formalisms. Corrections were derived for both Fermi and Gamow-Teller transitions, and methods of analytical evaluation thoroughly discussed. In its integrated form, calculated f values were in agreement with the most precise numerical results within the aimed for precision. The need for an accurate evaluation of weak magnetism contributions was stressed, and the possible significance of the oft-neglected induced pseudoscalar interaction was noted. Together with improved atomic corrections, an analytical description was presented of the allowed β spectrum shape accurate to a few parts in 10-4 down to 1 keV for low to medium Z nuclei, thereby extending the work by previous authors by nearly an order of magnitude.

  5. An Accurate Transmitting Power Control Method in Wireless Communication Transceivers

    NASA Astrophysics Data System (ADS)

    Zhang, Naikang; Wen, Zhiping; Hou, Xunping; Bi, Bo

    2018-01-01

    Power control circuits are widely used in transceivers aiming at stabilizing the transmitted signal power to a specified value, thereby reducing power consumption and interference to other frequency bands. In order to overcome the shortcomings of traditional modes of power control, this paper proposes an accurate signal power detection method by multiplexing the receiver and realizes transmitting power control in the digital domain. The simulation results show that this novel digital power control approach has advantages of small delay, high precision and simplified design procedure. The proposed method is applicable to transceivers working at large frequency dynamic range, and has good engineering practicability.

  6. Precision of DVC approaches for strain analysis in bone imaged with μCT at different dimensional levels.

    NASA Astrophysics Data System (ADS)

    Dall'Ara, Enrico; Peña-Fernández, Marta; Palanca, Marco; Giorgi, Mario; Cristofolini, Luca; Tozzi, Gianluca

    2017-11-01

    Accurate measurement of local strain in heterogeneous and anisotropic bone tissue is fundamental to understand the pathophysiology of musculoskeletal diseases, to evaluate the effect of interventions from preclinical studies, and to optimize the design and delivery of biomaterials. Digital volume correlation (DVC) can be used to measure the three-dimensional displacement and strain fields from micro-Computed Tomography (µCT) images of loaded specimens. However, this approach is affected by the quality of the input images, by the morphology and density of the tissue under investigation, by the correlation scheme, and by the operational parameters used in the computation. Therefore, for each application the precision of the method should be evaluated. In this paper we present the results collected from datasets analyzed in previous studies as well as new data from a recent experimental campaign for characterizing the relationship between the precision of two different DVC approaches and the spatial resolution of the outputs. Different bone structures scanned with laboratory source µCT or Synchrotron light µCT (SRµCT) were processed in zero-strain tests to evaluate the precision of the DVC methods as a function of the subvolume size that ranged from 8 to 2500 micrometers. The results confirmed that for every microstructure the precision of DVC improves for larger subvolume size, following power laws. However, for the first time large differences in the precision of both local and global DVC approaches have been highlighted when SRµCT or in vivo µCT images were used instead of conventional ex vivo µCT. These findings suggest that in situ mechanical testing protocols applied in SRµCT facilities should be optimized in order to allow DVC analyses of localized strain measurements. Moreover, for in vivo µCT applications DVC analyses should be performed only with relatively course spatial resolution for achieving a reasonable precision of the method. In conclusion

  7. Gene expression during blow fly development: improving the precision of age estimates in forensic entomology.

    PubMed

    Tarone, Aaron M; Foran, David R

    2011-01-01

    Forensic entomologists use size and developmental stage to estimate blow fly age, and from those, a postmortem interval. Since such estimates are generally accurate but often lack precision, particularly in the older developmental stages, alternative aging methods would be advantageous. Presented here is a means of incorporating developmentally regulated gene expression levels into traditional stage and size data, with a goal of more precisely estimating developmental age of immature Lucilia sericata. Generalized additive models of development showed improved statistical support compared to models that did not include gene expression data, resulting in an increase in estimate precision, especially for postfeeding third instars and pupae. The models were then used to make blind estimates of development for 86 immature L. sericata raised on rat carcasses. Overall, inclusion of gene expression data resulted in increased precision in aging blow flies. © 2010 American Academy of Forensic Sciences.

  8. The European Society for Medical Oncology (ESMO) Precision Medicine Glossary.

    PubMed

    Yates, L R; Seoane, J; Le Tourneau, C; Siu, L L; Marais, R; Michiels, S; Soria, J C; Campbell, P; Normanno, N; Scarpa, A; Reis-Filho, J S; Rodon, J; Swanton, C; Andre, F

    2018-01-01

    Precision medicine is rapidly evolving within the field of oncology and has brought many new concepts and terminologies that are often poorly defined when first introduced, which may subsequently lead to miscommunication within the oncology community. The European Society for Medical Oncology (ESMO) recognises these challenges and is committed to support the adoption of precision medicine in oncology. To add clarity to the language used by oncologists and basic scientists within the context of precision medicine, the ESMO Translational Research and Personalised Medicine Working Group has developed a standardised glossary of relevant terms. Relevant terms for inclusion in the glossary were identified via an ESMO member survey conducted in Autumn 2016, and by the ESMO Translational Research and Personalised Medicine Working Group members. Each term was defined by experts in the field, discussed and, if necessary, modified by the Working Group before reaching consensus approval. A literature search was carried out to determine which of the terms, 'precision medicine' and 'personalised medicine', is most appropriate to describe this field. A total of 43 terms are included in the glossary, grouped into five main themes-(i) mechanisms of decision, (ii) characteristics of molecular alterations, (iii) tumour characteristics, (iv) clinical trials and statistics and (v) new research tools. The glossary classes 'precision medicine' or 'personalised medicine' as technically interchangeable but the term 'precision medicine' is favoured as it more accurately reflects the highly precise nature of new technologies that permit base pair resolution dissection of cancer genomes and is less likely to be misinterpreted. The ESMO Precision Medicine Glossary provides a resource to facilitate consistent communication in this field by clarifying and raising awareness of the language employed in cancer research and oncology practice. The glossary will be a dynamic entity, undergoing

  9. Soil Macronutrient Sensing for Precision Agriculture

    USDA-ARS?s Scientific Manuscript database

    Accurate measurements of soil macronutrients (i.e., nitrogen, phosphorus, and potassium) are needed for efficient agricultural production, including site-specific crop management (SSCM), where fertilizer nutrient application rates are adjusted spatially based on local requirements. Rapid, non-destru...

  10. Precision Cleaning - Path to Premier

    NASA Technical Reports Server (NTRS)

    Mackler, Scott E.

    2008-01-01

    ITT Space Systems Division s new Precision Cleaning facility provides critical cleaning and packaging of aerospace flight hardware and optical payloads to meet customer performance requirements. The Precision Cleaning Path to Premier Project was a 2007 capital project and is a key element in the approved Premier Resource Management - Integrated Supply Chain Footprint Optimization Project. Formerly precision cleaning was located offsite in a leased building. A new facility equipped with modern precision cleaning equipment including advanced process analytical technology and improved capabilities was designed and built after outsourcing solutions were investigated and found lacking in ability to meet quality specifications and schedule needs. SSD cleans parts that can range in size from a single threaded fastener all the way up to large composite structures. Materials that can be processed include optics, composites, metals and various high performance coatings. We are required to provide verification to our customers that we have met their particulate and molecular cleanliness requirements and we have that analytical capability in this new facility. The new facility footprint is approximately half the size of the former leased operation and provides double the amount of throughput. Process improvements and new cleaning equipment are projected to increase 1st pass yield from 78% to 98% avoiding $300K+/yr in rework costs. Cost avoidance of $350K/yr will result from elimination of rent, IT services, transportation, and decreased utility costs. Savings due to reduced staff expected to net $4-500K/yr.

  11. Accurate LC peak boundary detection for ¹⁶O/¹⁸O labeled LC-MS data.

    PubMed

    Cui, Jian; Petritis, Konstantinos; Tegeler, Tony; Petritis, Brianne; Ma, Xuepo; Jin, Yufang; Gao, Shou-Jiang S J; Zhang, Jianqiu Michelle

    2013-01-01

    In liquid chromatography-mass spectrometry (LC-MS), parts of LC peaks are often corrupted by their co-eluting peptides, which results in increased quantification variance. In this paper, we propose to apply accurate LC peak boundary detection to remove the corrupted part of LC peaks. Accurate LC peak boundary detection is achieved by checking the consistency of intensity patterns within peptide elution time ranges. In addition, we remove peptides with erroneous mass assignment through model fitness check, which compares observed intensity patterns to theoretically constructed ones. The proposed algorithm can significantly improve the accuracy and precision of peptide ratio measurements.

  12. Precision agriculture in large-scale mechanized farming

    USDA-ARS?s Scientific Manuscript database

    Precision agriculture involves a great deal of technologies and requires additional investments of money and time, but it can be practiced at different levels depending on the specific field and crop conditions and the resources and technology services available to the farmer. If practiced properly,...

  13. Extracting accurate and precise topography from LROC narrow angle camera stereo observations

    NASA Astrophysics Data System (ADS)

    Henriksen, M. R.; Manheim, M. R.; Burns, K. N.; Seymour, P.; Speyerer, E. J.; Deran, A.; Boyd, A. K.; Howington-Kraus, E.; Rosiek, M. R.; Archinal, B. A.; Robinson, M. S.

    2017-02-01

    The Lunar Reconnaissance Orbiter Camera (LROC) includes two identical Narrow Angle Cameras (NAC) that each provide 0.5 to 2.0 m scale images of the lunar surface. Although not designed as a stereo system, LROC can acquire NAC stereo observations over two or more orbits using at least one off-nadir slew. Digital terrain models (DTMs) are generated from sets of stereo images and registered to profiles from the Lunar Orbiter Laser Altimeter (LOLA) to improve absolute accuracy. With current processing methods, DTMs have absolute accuracies better than the uncertainties of the LOLA profiles and relative vertical and horizontal precisions less than the pixel scale of the DTMs (2-5 m). We computed slope statistics from 81 highland and 31 mare DTMs across a range of baselines. For a baseline of 15 m the highland mean slope parameters are: median = 9.1°, mean = 11.0°, standard deviation = 7.0°. For the mare the mean slope parameters are: median = 3.5°, mean = 4.9°, standard deviation = 4.5°. The slope values for the highland terrain are steeper than previously reported, likely due to a bias in targeting of the NAC DTMs toward higher relief features in the highland terrain. Overlapping DTMs of single stereo sets were also combined to form larger area DTM mosaics that enable detailed characterization of large geomorphic features. From one DTM mosaic we mapped a large viscous flow related to the Orientale basin ejecta and estimated its thickness and volume to exceed 300 m and 500 km3, respectively. Despite its ∼3.8 billion year age the flow still exhibits unconfined margin slopes above 30°, in some cases exceeding the angle of repose, consistent with deposition of material rich in impact melt. We show that the NAC stereo pairs and derived DTMs represent an invaluable tool for science and exploration purposes. At this date about 2% of the lunar surface is imaged in high-resolution stereo, and continued acquisition of stereo observations will serve to strengthen our

  14. Computing many-body wave functions with guaranteed precision: the first-order Møller-Plesset wave function for the ground state of helium atom.

    PubMed

    Bischoff, Florian A; Harrison, Robert J; Valeev, Edward F

    2012-09-14

    We present an approach to compute accurate correlation energies for atoms and molecules using an adaptive discontinuous spectral-element multiresolution representation for the two-electron wave function. Because of the exponential storage complexity of the spectral-element representation with the number of dimensions, a brute-force computation of two-electron (six-dimensional) wave functions with high precision was not practical. To overcome the key storage bottlenecks we utilized (1) a low-rank tensor approximation (specifically, the singular value decomposition) to compress the wave function, and (2) explicitly correlated R12-type terms in the wave function to regularize the Coulomb electron-electron singularities of the Hamiltonian. All operations necessary to solve the Schrödinger equation were expressed so that the reconstruction of the full-rank form of the wave function is never necessary. Numerical performance of the method was highlighted by computing the first-order Møller-Plesset wave function of a helium atom. The computed second-order Møller-Plesset energy is precise to ~2 microhartrees, which is at the precision limit of the existing general atomic-orbital-based approaches. Our approach does not assume special geometric symmetries, hence application to molecules is straightforward.

  15. The need for accurate total cholesterol measurement. Recommended analytical goals, current state of reliability, and guidelines for better determinations.

    PubMed

    Naito, H K

    1989-03-01

    We have approached a dawn of a new era in detection, evaluation, treatment, and monitoring of individuals with elevated blood cholesterol levels who are at increased risk for CHD. The NHLBI's National Cholesterol Education Program will be the major force underlying this national awareness program, which is dependent on the clinical laboratories providing reliable data. Precision or reproducibility of results is not a problem for most of the laboratories, but accuracy is a major concern. Both the manufacturers and laboratorians need to standardize the measurement for cholesterol so that the accuracy base is traceable to the NCCLS NRS/CHOL. The manufacturers need to adopt a uniform policy that will ensure that the values assigned to calibration, quality control, and quality assurance or survey materials are accurate and traceable to the NCCLS/CHOL. Since, at present, there are some limitations of these materials caused by matrix effects, laboratories are encouraged to use the CDC-NHLBI National Reference Laboratory Network to evaluate and monitor their ability to measure patient blood cholesterol levels accurately. Major areas of analytical problems are identified and general, as well as specific, recommendations are provided to help ensure reliable measurement of cholesterol in patient specimens.

  16. A Monte Carlo Simulation Comparing the Statistical Precision of Two High-Stakes Teacher Evaluation Methods: A Value-Added Model and a Composite Measure

    ERIC Educational Resources Information Center

    Spencer, Bryden

    2016-01-01

    Value-added models are a class of growth models used in education to assign responsibility for student growth to teachers or schools. For value-added models to be used fairly, sufficient statistical precision is necessary for accurate teacher classification. Previous research indicated precision below practical limits. An alternative approach has…

  17. Precision Medicine in Myelodysplastic Syndromes and Leukemias: Lessons from Sequential Mutations.

    PubMed

    Nazha, Aziz; Sekeres, Mikkael A

    2017-01-14

    Precision medicine can be simply defined as the identification of personalized treatment that matches patient-specific clinical and genomic characteristics. Since the completion of the Human Genome Project in 2003, significant advances have been made in our understanding of the genetic makeup of diseases, especially cancers. The identification of somatic mutations that can drive cancer has led to the development of therapies that specifically target the abnormal proteins derived from these mutations. This has led to a paradigm shift in our treatment methodology. Although some success has been achieved in targeting some genetic abnormalities, several challenges and limitations exist when applying precision-medicine concepts in leukemia and myelodysplastic syndromes. We review the current understanding of genomics in myelodysplastic syndromes (MDS) and leukemias and the limitations of precision-medicine concepts in MDS.

  18. Precision enhancement of pavement roughness localization with connected vehicles

    NASA Astrophysics Data System (ADS)

    Bridgelall, R.; Huang, Y.; Zhang, Z.; Deng, F.

    2016-02-01

    Transportation agencies rely on the accurate localization and reporting of roadway anomalies that could pose serious hazards to the traveling public. However, the cost and technical limitations of present methods prevent their scaling to all roadways. Connected vehicles with on-board accelerometers and conventional geospatial position receivers offer an attractive alternative because of their potential to monitor all roadways in real-time. The conventional global positioning system is ubiquitous and essentially free to use but it produces impractically large position errors. This study evaluated the improvement in precision achievable by augmenting the conventional geo-fence system with a standard speed bump or an existing anomaly at a pre-determined position to establish a reference inertial marker. The speed sensor subsequently generates position tags for the remaining inertial samples by computing their path distances relative to the reference position. The error model and a case study using smartphones to emulate connected vehicles revealed that the precision in localization improves from tens of metres to sub-centimetre levels, and the accuracy of measuring localized roughness more than doubles. The research results demonstrate that transportation agencies will benefit from using the connected vehicle method to achieve precision and accuracy levels that are comparable to existing laser-based inertial profilers.

  19. High precision measurements on fission-fragment de-excitation

    NASA Astrophysics Data System (ADS)

    Oberstedt, Stephan; Gatera, Angélique; Geerts, Wouter; Göök, Alf; Hambsch, Franz-Josef; Vidali, Marzio; Oberstedt, Andreas

    2017-11-01

    In recent years nuclear fission has gained renewed interest both from the nuclear energy community and in basic science. The first, represented by the OECD Nuclear Energy Agency, expressed the need for more accurate fission cross-section and fragment yield data for safety assessments of Generation IV reactor systems. In basic science modelling made much progress in describing the de-excitation mechanism of neutron-rich isotopes, e.g. produced in nuclear fission. Benchmarking the different models require a precise experimental data on prompt fission neutron and γ-ray emission, e.g. multiplicity, average energy per particle and total dissipated energy per fission, preferably as function of fission-fragment mass and total kinetic energy. A collaboration of scientists from JRC Geel (formerly known as JRC IRMM) and other institutes took the lead in establishing a dedicated measurement programme on prompt fission neutron and γ-ray characteristics, which has triggered even more measurement activities around the world. This contribution presents new advanced instrumentation and methodology we use to generate high-precision spectral data and will give a flavour of future data needs and opportunities.

  20. Enhanced Precision Time Synchronization for Wireless Sensor Networks

    PubMed Central

    Cho, Hyuntae; Kim, Jongdeok; Baek, Yunju

    2011-01-01

    Time synchronization in wireless sensor networks (WSNs) is a fundamental issue for the coordination of distributed entities and events. Nondeterministic latency, which may decrease the accuracy and precision of time synchronization can occur at any point in the network layers. Specially, random back-off by channel contention leads to a large uncertainty. In order to reduce the large nondeterministic uncertainty from channel contention, we propose an enhanced precision time synchronization protocol in this paper. The proposed method reduces the traffic needed for the synchronization procedure by selectively forwarding the packet. Furthermore, the time difference between sensor nodes increases as time advances because of the use of a clock source with a cheap crystal oscillator. In addition, we provide a means to maintain accurate time by adopting hardware-assisted time stamp and drift correction. Experiments are conducted to evaluate the performance of the proposed method, for which sensor nodes are designed and implemented. According to the evaluation results, the performance of the proposed method is better than that of a traditional time synchronization protocol. PMID:22164035

  1. Enhanced precision time synchronization for wireless sensor networks.

    PubMed

    Cho, Hyuntae; Kim, Jongdeok; Baek, Yunju

    2011-01-01

    Time synchronization in wireless sensor networks (WSNs) is a fundamental issue for the coordination of distributed entities and events. Nondeterministic latency, which may decrease the accuracy and precision of time synchronization can occur at any point in the network layers. Specially, random back-off by channel contention leads to a large uncertainty. In order to reduce the large nondeterministic uncertainty from channel contention, we propose an enhanced precision time synchronization protocol in this paper. The proposed method reduces the traffic needed for the synchronization procedure by selectively forwarding the packet. Furthermore, the time difference between sensor nodes increases as time advances because of the use of a clock source with a cheap crystal oscillator. In addition, we provide a means to maintain accurate time by adopting hardware-assisted time stamp and drift correction. Experiments are conducted to evaluate the performance of the proposed method, for which sensor nodes are designed and implemented. According to the evaluation results, the performance of the proposed method is better than that of a traditional time synchronization protocol.

  2. Evaluation of the precision agricultural landscape modeling system (PALMS) in the semiarid Texas southern high plains

    USDA-ARS?s Scientific Manuscript database

    Accurate models to simulate the soil water balance in semiarid cropping systems are needed to evaluate management practices for soil and water conservation in both irrigated and dryland production systems. The objective of this study was to evaluate the application of the Precision Agricultural Land...

  3. Evaluation of the Precision Agricultural Landscape Modeling System (PALMS) in the Semiarid Texas Southern High Plains

    USDA-ARS?s Scientific Manuscript database

    Accurate models to simulate the soil water balance in semiarid cropping systems are needed to evaluate management practices for soil and water conservation in both irrigated and dryland production systems. The objective of this study was to evaluate the application of the Precision Agricultural Land...

  4. Conducting Precision Medicine Research with African Americans.

    PubMed

    Halbert, Chanita Hughes; McDonald, Jasmine; Vadaparampil, Susan; Rice, LaShanta; Jefferson, Melanie

    2016-01-01

    Precision medicine is an approach to detecting, treating, and managing disease that is based on individual variation in genetic, environmental, and lifestyle factors. Precision medicine is expected to reduce health disparities, but this will be possible only if studies have adequate representation of racial minorities. It is critical to anticipate the rates at which individuals from diverse populations are likely to participate in precision medicine studies as research initiatives are being developed. We evaluated the likelihood of participating in a clinical study for precision medicine. Observational study conducted between October 2010 and February 2011 in a national sample of African Americans. Intentions to participate in a government sponsored study that involves providing a biospecimen and generates data that could be shared with other researchers to conduct future studies. One third of respondents would participate in a clinical study for precision medicine. Only gender had a significant independent association with participation intentions. Men had a 1.86 (95% CI = 1.11, 3.12, p = 0.02) increased likelihood of participating in a precision medicine study compared to women in the model that included overall barriers and facilitators. In the model with specific participation barriers, distrust was associated with a reduced likelihood of participating in the research described in the vignette (OR = 0.57, 95% CI = 0.34, 0.96, p = 0.04). African Americans may have low enrollment in PMI research. As PMI research is implemented, extensive efforts will be needed to ensure adequate representation. Additional research is needed to identify optimal ways of ethically describing precision medicine studies to ensure sufficient recruitment of racial minorities.

  5. Precision Robotic Assembly Machine

    ScienceCinema

    None

    2017-12-09

    The world's largest laser system is the National Ignition Facility (NIF), located at Lawrence Livermore National Laboratory. NIF's 192 laser beams are amplified to extremely high energy, and then focused onto a tiny target about the size of a BB, containing frozen hydrogen gas. The target must be perfectly machined to incredibly demanding specifications. The Laboratory's scientists and engineers have developed a device called the "Precision Robotic Assembly Machine" for this purpose. Its unique design won a prestigious R&D-100 award from R&D Magazine.

  6. Approaches for the accurate definition of geological time boundaries

    NASA Astrophysics Data System (ADS)

    Schaltegger, Urs; Baresel, Björn; Ovtcharova, Maria; Goudemand, Nicolas; Bucher, Hugo

    2015-04-01

    Which strategies lead to the most precise and accurate date of a given geological boundary? Geological units are usually defined by the occurrence of characteristic taxa and hence boundaries between these geological units correspond to dramatic faunal and/or floral turnovers and they are primarily defined using first or last occurrences of index species, or ideally by the separation interval between two consecutive, characteristic associations of fossil taxa. These boundaries need to be defined in a way that enables their worldwide recognition and correlation across different stratigraphic successions, using tools as different as bio-, magneto-, and chemo-stratigraphy, and astrochronology. Sedimentary sequences can be dated in numerical terms by applying high-precision chemical-abrasion, isotope-dilution, thermal-ionization mass spectrometry (CA-ID-TIMS) U-Pb age determination to zircon (ZrSiO4) in intercalated volcanic ashes. But, though volcanic activity is common in geological history, ashes are not necessarily close to the boundary we would like to date precisely and accurately. In addition, U-Pb zircon data sets may be very complex and difficult to interpret in terms of the age of ash deposition. To overcome these difficulties we use a multi-proxy approach we applied to the precise and accurate dating of the Permo-Triassic and Early-Middle Triassic boundaries in South China. a) Dense sampling of ashes across the critical time interval and a sufficiently large number of analysed zircons per ash sample can guarantee the recognition of all system complexities. Geochronological datasets from U-Pb dating of volcanic zircon may indeed combine effects of i) post-crystallization Pb loss from percolation of hydrothermal fluids (even using chemical abrasion), with ii) age dispersion from prolonged residence of earlier crystallized zircon in the magmatic system. As a result, U-Pb dates of individual zircons are both apparently younger and older than the depositional age

  7. Fundamentals of Pharmacogenetics in Personalized, Precision Medicine.

    PubMed

    Valdes, Roland; Yin, DeLu Tyler

    2016-09-01

    This article introduces fundamental principles of pharmacogenetics as applied to personalized and precision medicine. Pharmacogenetics establishes relationships between pharmacology and genetics by connecting phenotypes and genotypes in predicting the response of therapeutics in individual patients. We describe differences between precision and personalized medicine and relate principles of pharmacokinetics and pharmacodynamics to applications in laboratory medicine. We also review basic principles of pharmacogenetics, including its evolution, how it enables the practice of personalized therapeutics, and the role of the clinical laboratory. These fundamentals are a segue for understanding specific clinical applications of pharmacogenetics described in subsequent articles in this issue. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Effect of plot and sample size on timing and precision of urban forest assessments

    Treesearch

    David J. Nowak; Jeffrey T. Walton; Jack C. Stevens; Daniel E. Crane; Robert E. Hoehn

    2008-01-01

    Accurate field data can be used to assess ecosystem services from trees and to improve urban forest management, yet little is known about the optimization of field data collection in the urban environment. Various field and Geographic Information System (GIS) tests were performed to help understand how time costs and precision of tree population estimates change with...

  9. A comparison of force and acoustic emission sensors in monitoring precision cylindrical grinding; Technical Digest

    NASA Astrophysics Data System (ADS)

    Marsh, Eric R.; Couey, Jeremiah A.; Knapp, Byron R.; Vallance, R. R.

    2005-05-01

    Aerostatic spindles are used in precision grinding applications requiring high stiffness and very low error motions (5 to 25 nm). Forces generated during precision grinding are small and present challenges for accurate and reliable process monitoring. These challenges are met by incorporating non-contact displacement sensors into an aerostatic spindle that are calibrated to measure grinding forces from rotor motion. Four experiments compare this force-sensing approach to acoustic emission (AE) in detecting workpiece contact, process monitoring with small depths of cut, detecting workpiece defects, and evaluating abrasive wheel wear/loading. Results indicate that force measurements are preferable to acoustic emission in precision grinding since the force sensor offers improved contact sensitivity, higher resolution, and is capable of detecting events occurring within a single revolution of the grinding wheel.

  10. System for precise position registration

    DOEpatents

    Sundelin, Ronald M.; Wang, Tong

    2005-11-22

    An apparatus for enabling accurate retaining of a precise position, such as for reacquisition of a microscopic spot or feature having a size of 0.1 mm or less, on broad-area surfaces after non-in situ processing. The apparatus includes a sample and sample holder. The sample holder includes a base and three support posts. Two of the support posts interact with a cylindrical hole and a U-groove in the sample to establish location of one point on the sample and a line through the sample. Simultaneous contact of the third support post with the surface of the sample defines a plane through the sample. All points of the sample are therefore uniquely defined by the sample and sample holder. The position registration system of the current invention provides accuracy, as measured in x, y repeatability, of at least 140 .mu.m.

  11. Precision measurements of linear scattering density using muon tomography

    NASA Astrophysics Data System (ADS)

    Åström, E.; Bonomi, G.; Calliari, I.; Calvini, P.; Checchia, P.; Donzella, A.; Faraci, E.; Forsberg, F.; Gonella, F.; Hu, X.; Klinger, J.; Sundqvist Ökvist, L.; Pagano, D.; Rigoni, A.; Ramous, E.; Urbani, M.; Vanini, S.; Zenoni, A.; Zumerle, G.

    2016-07-01

    We demonstrate that muon tomography can be used to precisely measure the properties of various materials. The materials which have been considered have been extracted from an experimental blast furnace, including carbon (coke) and iron oxides, for which measurements of the linear scattering density relative to the mass density have been performed with an absolute precision of 10%. We report the procedures that are used in order to obtain such precision, and a discussion is presented to address the expected performance of the technique when applied to heavier materials. The results we obtain do not depend on the specific type of material considered and therefore they can be extended to any application.

  12. Precision powder feeder

    DOEpatents

    Schlienger, M. Eric; Schmale, David T.; Oliver, Michael S.

    2001-07-10

    A new class of precision powder feeders is disclosed. These feeders provide a precision flow of a wide range of powdered materials, while remaining robust against jamming or damage. These feeders can be precisely controlled by feedback mechanisms.

  13. High-Precision Timing of Several Millisecond Pulsars

    NASA Astrophysics Data System (ADS)

    Ferdman, R. D.; Stairs, I. H.; Backer, D. C.; Ramachandran, R.; Demorest, P.; Nice, D. J.; Lyne, A. G.; Kramer, M.; Lorimer, D.; McLaughlin, M.; Manchester, D.; Camilo, F.; D'Amico, N.; Possenti, A.; Burgay, M.; Joshi, B. C.; Freire, P. C.

    2004-12-01

    The highest precision pulsar timing is achieved by reproducing as accurately as possible the pulse profile as emitted by the pulsar, in high signal-to-noise observations. The best profile reconstruction can be accomplished with several-bit voltage sampling and coherent removal of the dispersion suffered by pulsar signals as they traverse the interstellar medium. The Arecibo Signal Processor (ASP) and its counterpart the Green Bank Astronomical Signal Processor (GASP) are flexible, state-of-the-art wide-bandwidth observing systems, built primarily for high-precision long-term timing of millisecond and binary pulsars. ASP and GASP are in use at the 300-m Arecibo telescope in Puerto Rico and the 100-m Green Bank Telescope in Green Bank, West Virginia, respectively, taking advantage of the enormous sensitivities of these telescopes. These instruments result in high-precision science through 4 and 8-bit sampling and perform coherent dedispersion on the incoming data stream in real or near-real time. This is done using a network of personal computers, over an observing bandwidth of 64 to 128 MHz, in each of two polarizations. We present preliminary results of timing and polarimetric observations with ASP/GASP for several pulsars, including the recently-discovered relativistic double-pulsar binary J0737-3039. These data are compared to simultaneous observations with other pulsar instruments, such as the new "spigot card" spectrometer on the GBT and the Princeton Mark IV instrument at Arecibo, the precursor timing system to ASP. We also briefly discuss several upcoming observations with ASP/GASP.

  14. Precision Medicine and PET/Computed Tomography in Melanoma.

    PubMed

    Mena, Esther; Sanli, Yasemin; Marcus, Charles; Subramaniam, Rathan M

    2017-10-01

    Recent advances in genomic profiling and sequencing of melanoma have provided new insights into the development of the basis for molecular biology to more accurately subgroup patients with melanoma. The development of novel mutation-targeted and immunomodulation therapy as a major component of precision oncology has revolutionized the management and outcome of patients with metastatic melanoma. PET imaging plays an important role in noninvasively assessing the tumor biological behavior, to guide individualized treatment and assess response to therapy. This review summarizes the recent genomic discoveries in melanoma in the era of targeted therapy and their implications for functional PET imaging. Published by Elsevier Inc.

  15. Development of MMC Gamma Detectors for Precise Characterization of Uranium Isotopes

    NASA Astrophysics Data System (ADS)

    Kim, G. B.; Flynn, C. C.; Kempf, S.; Gastaldo, L.; Fleischmann, A.; Enss, C.; Friedrich, S.

    2018-06-01

    Precise nuclear data from radioactive decays are important for the accurate non-destructive assay of fissile materials in nuclear safeguards. We are developing high energy resolution gamma detectors based on metallic magnetic calorimeters (MMCs) to accurately measure gamma-ray energies and branching ratios of uranium isotopes. Our MMC gamma detectors exhibit good linearity, reproducibility and a consistent response function for low energy gamma-rays. We illustrate the capabilities of MMCs to improve literature values of nuclear data with an analysis of gamma spectra of U-233. In this context, we also improve the value of the energy for the single gamma-ray of the U-233 daughter Ra-225 by over an order of magnitude from 40.09 ± 0.05 to 40.0932 ± 0.0007 keV.

  16. Exploratory Movement Generates Higher-Order Information That Is Sufficient for Accurate Perception of Scaled Egocentric Distance

    PubMed Central

    Mantel, Bruno; Stoffregen, Thomas A.; Campbell, Alain; Bardy, Benoît G.

    2015-01-01

    Body movement influences the structure of multiple forms of ambient energy, including optics and gravito-inertial force. Some researchers have argued that egocentric distance is derived from inferential integration of visual and non-visual stimulation. We suggest that accurate information about egocentric distance exists in perceptual stimulation as higher-order patterns that extend across optics and inertia. We formalize a pattern that specifies the egocentric distance of a stationary object across higher-order relations between optics and inertia. This higher-order parameter is created by self-generated movement of the perceiver in inertial space relative to the illuminated environment. For this reason, we placed minimal restrictions on the exploratory movements of our participants. We asked whether humans can detect and use the information available in this higher-order pattern. Participants judged whether a virtual object was within reach. We manipulated relations between body movement and the ambient structure of optics and inertia. Judgments were precise and accurate when the higher-order optical-inertial parameter was available. When only optic flow was available, judgments were poor. Our results reveal that participants perceived egocentric distance from the higher-order, optical-inertial consequences of their own exploratory activity. Analysis of participants’ movement trajectories revealed that self-selected movements were complex, and tended to optimize availability of the optical-inertial pattern that specifies egocentric distance. We argue that accurate information about egocentric distance exists in higher-order patterns of ambient energy, that self-generated movement can generate these higher-order patterns, and that these patterns can be detected and used to support perception of egocentric distance that is precise and accurate. PMID:25856410

  17. Dr. Kenneth Sudduth: A giant pioneering precision agriculture

    USDA-ARS?s Scientific Manuscript database

    Dr. Ken Sudduth is nationally and internationally recognized for his precision agriculture research and leadership, especially in the areas of soil sensing and assessment of spatial variability for site-specific management. His many noteworthy contributions include novel techniques and methodology f...

  18. On the importance of 3D, geometrically accurate, and subject-specific finite element analysis for evaluation of in-vivo soft tissue loads.

    PubMed

    Moerman, Kevin M; van Vijven, Marc; Solis, Leandro R; van Haaften, Eline E; Loenen, Arjan C Y; Mushahwar, Vivian K; Oomens, Cees W J

    2017-04-01

    Pressure ulcers are a type of local soft tissue injury due to sustained mechanical loading and remain a common issue in patient care. People with spinal cord injury (SCI) are especially at risk of pressure ulcers due to impaired mobility and sensory perception. The development of load improving support structures relies on realistic tissue load evaluation e.g. using finite element analysis (FEA). FEA requires realistic subject-specific mechanical properties and geometries. This study focuses on the effect of geometry. MRI is used for the creation of geometrically accurate models of the human buttock for three able-bodied volunteers and three volunteers with SCI. The effect of geometry on observed internal tissue deformations for each subject is studied by comparing FEA findings for equivalent loading conditions. The large variations found between subjects confirms the importance of subject-specific FEA.

  19. A new sensor system for accurate and precise determination of sediment dynamics and position.

    NASA Astrophysics Data System (ADS)

    Maniatis, Georgios; Hoey, Trevor; Sventek, Joseph; Hodge, Rebecca

    2014-05-01

    Sediment transport processes control many significant geomorphological changes. Consequently, sediment transport dynamics are studied across a wide range of scales leading to application of a variety of conceptually different mathematical descriptions (models) and data acquisition techniques (sensing). For river sediment transport processes both Eulerian and Lagrangian formulations are used. Data are gathered using a very wide range of sensing techniques that are not always compatible with the conceptual formulation applied. We are concerned with small to medium sediment grain-scale motion in gravel-bed rivers, and other coarse-grained environments, and: a) are developing a customised environmental sensor capable of providing coherent data that reliably record the motion; and, b) provide a mathematical framework in which these data can be analysed and interpreted, this being compatible with current stochastic approaches to sediment transport theory. Here we present results from three different aspects of the above developmental process. Firstly, we present a requirement analysis for the sensor based on the state of the art of the existing technologies. We focus on the factors that enhance data coherence and representativeness, extending the common practice for optimization which is based exclusively on electronics/computing related criteria. This analysis leads to formalization of a method that permits accurate control on the physical properties of the sensor using contemporary rapid prototyping techniques [Maniatis et al. 2013]. Secondly the first results are presented from a series of entrainment experiments in a 5 x 0.8 m flume in which a prototype sensor was deployed to monitor entrainment dynamics under increasing flow conditions (0.037 m3.s-1). The sensor was enclosed in an idealized spherical case (111 mm diameter) and placed on a constructed bed of hemispheres of the same diameter. We measured 3-axial inertial acceleration (as a measure of flow stress

  20. Lidar Systems for Precision Navigation and Safe Landing on Planetary Bodies

    NASA Technical Reports Server (NTRS)

    Amzajerdian, Farzin; Pierrottet, Diego F.; Petway, Larry B.; Hines, Glenn D.; Roback, Vincent E.

    2011-01-01

    The ability of lidar technology to provide three-dimensional elevation maps of the terrain, high precision distance to the ground, and approach velocity can enable safe landing of robotic and manned vehicles with a high degree of precision. Currently, NASA is developing novel lidar sensors aimed at needs of future planetary landing missions. These lidar sensors are a 3-Dimensional Imaging Flash Lidar, a Doppler Lidar, and a Laser Altimeter. The Flash Lidar is capable of generating elevation maps of the terrain that indicate hazardous features such as rocks, craters, and steep slopes. The elevation maps collected during the approach phase of a landing vehicle, at about 1 km above the ground, can be used to determine the most suitable safe landing site. The Doppler Lidar provides highly accurate ground relative velocity and distance data allowing for precision navigation to the landing site. Our Doppler lidar utilizes three laser beams pointed to different directions to measure line of sight velocities and ranges to the ground from altitudes of over 2 km. Throughout the landing trajectory starting at altitudes of about 20 km, the Laser Altimeter can provide very accurate ground relative altitude measurements that are used to improve the vehicle position knowledge obtained from the vehicle navigation system. At altitudes from approximately 15 km to 10 km, either the Laser Altimeter or the Flash Lidar can be used to generate contour maps of the terrain, identifying known surface features such as craters, to perform Terrain relative Navigation thus further reducing the vehicle s relative position error. This paper describes the operational capabilities of each lidar sensor and provides a status of their development. Keywords: Laser Remote Sensing, Laser Radar, Doppler Lidar, Flash Lidar, 3-D Imaging, Laser Altimeter, Precession Landing, Hazard Detection

  1. Natural Language Processing Accurately Calculates Adenoma and Sessile Serrated Polyp Detection Rates.

    PubMed

    Nayor, Jennifer; Borges, Lawrence F; Goryachev, Sergey; Gainer, Vivian S; Saltzman, John R

    2018-07-01

    ADR is a widely used colonoscopy quality indicator. Calculation of ADR is labor-intensive and cumbersome using current electronic medical databases. Natural language processing (NLP) is a method used to extract meaning from unstructured or free text data. (1) To develop and validate an accurate automated process for calculation of adenoma detection rate (ADR) and serrated polyp detection rate (SDR) on data stored in widely used electronic health record systems, specifically Epic electronic health record system, Provation ® endoscopy reporting system, and Sunquest PowerPath pathology reporting system. Screening colonoscopies performed between June 2010 and August 2015 were identified using the Provation ® reporting tool. An NLP pipeline was developed to identify adenomas and sessile serrated polyps (SSPs) on pathology reports corresponding to these colonoscopy reports. The pipeline was validated using a manual search. Precision, recall, and effectiveness of the natural language processing pipeline were calculated. ADR and SDR were then calculated. We identified 8032 screening colonoscopies that were linked to 3821 pathology reports (47.6%). The NLP pipeline had an accuracy of 100% for adenomas and 100% for SSPs. Mean total ADR was 29.3% (range 14.7-53.3%); mean male ADR was 35.7% (range 19.7-62.9%); and mean female ADR was 24.9% (range 9.1-51.0%). Mean total SDR was 4.0% (0-9.6%). We developed and validated an NLP pipeline that accurately and automatically calculates ADRs and SDRs using data stored in Epic, Provation ® and Sunquest PowerPath. This NLP pipeline can be used to evaluate colonoscopy quality parameters at both individual and practice levels.

  2. Magnetic resonance imaging for precise radiotherapy of small laboratory animals.

    PubMed

    Frenzel, Thorsten; Kaul, Michael Gerhard; Ernst, Thomas Michael; Salamon, Johannes; Jäckel, Maria; Schumacher, Udo; Krüll, Andreas

    2017-03-01

    Radiotherapy of small laboratory animals (SLA) is often not as precisely applied as in humans. Here we describe the use of a dedicated SLA magnetic resonance imaging (MRI) scanner for precise tumor volumetry, radiotherapy treatment planning, and diagnostic imaging in order to make the experiments more accurate. Different human cancer cells were injected at the lower trunk of pfp/rag2 and SCID mice to allow for local tumor growth. Data from cross sectional MRI scans were transferred to a clinical treatment planning system (TPS) for humans. Manual palpation of the tumor size was compared with calculated tumor size of the TPS and with tumor weight at necropsy. As a feasibility study MRI based treatment plans were calculated for a clinical 6MV linear accelerator using a micro multileaf collimator (μMLC). In addition, diagnostic MRI scans were used to investigate animals which did clinical poorly during the study. MRI is superior in precise tumor volume definition whereas manual palpation underestimates their size. Cross sectional MRI allow for treatment planning so that conformal irradiation of mice with a clinical linear accelerator using a μMLC is in principle feasible. Several internal pathologies were detected during the experiment using the dedicated scanner. MRI is a key technology for precise radiotherapy of SLA. The scanning protocols provided are suited for tumor volumetry, treatment planning, and diagnostic imaging. Copyright © 2016. Published by Elsevier GmbH.

  3. Methods for applying accurate digital PCR analysis on low copy DNA samples.

    PubMed

    Whale, Alexandra S; Cowen, Simon; Foy, Carole A; Huggett, Jim F

    2013-01-01

    Digital PCR (dPCR) is a highly accurate molecular approach, capable of precise measurements, offering a number of unique opportunities. However, in its current format dPCR can be limited by the amount of sample that can be analysed and consequently additional considerations such as performing multiplex reactions or pre-amplification can be considered. This study investigated the impact of duplexing and pre-amplification on dPCR analysis by using three different assays targeting a model template (a portion of the Arabidopsis thaliana alcohol dehydrogenase gene). We also investigated the impact of different template types (linearised plasmid clone and more complex genomic DNA) on measurement precision using dPCR. We were able to demonstrate that duplex dPCR can provide a more precise measurement than uniplex dPCR, while applying pre-amplification or varying template type can significantly decrease the precision of dPCR. Furthermore, we also demonstrate that the pre-amplification step can introduce measurement bias that is not consistent between experiments for a sample or assay and so could not be compensated for during the analysis of this data set. We also describe a model for estimating the prevalence of molecular dropout and identify this as a source of dPCR imprecision. Our data have demonstrated that the precision afforded by dPCR at low sample concentration can exceed that of the same template post pre-amplification thereby negating the need for this additional step. Our findings also highlight the technical differences between different templates types containing the same sequence that must be considered if plasmid DNA is to be used to assess or control for more complex templates like genomic DNA.

  4. Methods for Applying Accurate Digital PCR Analysis on Low Copy DNA Samples

    PubMed Central

    Whale, Alexandra S.; Cowen, Simon; Foy, Carole A.; Huggett, Jim F.

    2013-01-01

    Digital PCR (dPCR) is a highly accurate molecular approach, capable of precise measurements, offering a number of unique opportunities. However, in its current format dPCR can be limited by the amount of sample that can be analysed and consequently additional considerations such as performing multiplex reactions or pre-amplification can be considered. This study investigated the impact of duplexing and pre-amplification on dPCR analysis by using three different assays targeting a model template (a portion of the Arabidopsis thaliana alcohol dehydrogenase gene). We also investigated the impact of different template types (linearised plasmid clone and more complex genomic DNA) on measurement precision using dPCR. We were able to demonstrate that duplex dPCR can provide a more precise measurement than uniplex dPCR, while applying pre-amplification or varying template type can significantly decrease the precision of dPCR. Furthermore, we also demonstrate that the pre-amplification step can introduce measurement bias that is not consistent between experiments for a sample or assay and so could not be compensated for during the analysis of this data set. We also describe a model for estimating the prevalence of molecular dropout and identify this as a source of dPCR imprecision. Our data have demonstrated that the precision afforded by dPCR at low sample concentration can exceed that of the same template post pre-amplification thereby negating the need for this additional step. Our findings also highlight the technical differences between different templates types containing the same sequence that must be considered if plasmid DNA is to be used to assess or control for more complex templates like genomic DNA. PMID:23472156

  5. Sample allocation balancing overall representativeness and stratum precision.

    PubMed

    Diaz-Quijano, Fredi Alexander

    2018-05-07

    In large-scale surveys, it is often necessary to distribute a preset sample size among a number of strata. Researchers must make a decision between prioritizing overall representativeness or precision of stratum estimates. Hence, I evaluated different sample allocation strategies based on stratum size. The strategies evaluated herein included allocation proportional to stratum population; equal sample for all strata; and proportional to the natural logarithm, cubic root, and square root of the stratum population. This study considered the fact that, from a preset sample size, the dispersion index of stratum sampling fractions is correlated with the population estimator error and the dispersion index of stratum-specific sampling errors would measure the inequality in precision distribution. Identification of a balanced and efficient strategy was based on comparing those both dispersion indices. Balance and efficiency of the strategies changed depending on overall sample size. As the sample to be distributed increased, the most efficient allocation strategies were equal sample for each stratum; proportional to the logarithm, to the cubic root, to square root; and that proportional to the stratum population, respectively. Depending on sample size, each of the strategies evaluated could be considered in optimizing the sample to keep both overall representativeness and stratum-specific precision. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Automatical and accurate segmentation of cerebral tissues in fMRI dataset with combination of image processing and deep learning

    NASA Astrophysics Data System (ADS)

    Kong, Zhenglun; Luo, Junyi; Xu, Shengpu; Li, Ting

    2018-02-01

    Image segmentation plays an important role in medical science. One application is multimodality imaging, especially the fusion of structural imaging with functional imaging, which includes CT, MRI and new types of imaging technology such as optical imaging to obtain functional images. The fusion process require precisely extracted structural information, in order to register the image to it. Here we used image enhancement, morphometry methods to extract the accurate contours of different tissues such as skull, cerebrospinal fluid (CSF), grey matter (GM) and white matter (WM) on 5 fMRI head image datasets. Then we utilized convolutional neural network to realize automatic segmentation of images in deep learning way. Such approach greatly reduced the processing time compared to manual and semi-automatic segmentation and is of great importance in improving speed and accuracy as more and more samples being learned. The contours of the borders of different tissues on all images were accurately extracted and 3D visualized. This can be used in low-level light therapy and optical simulation software such as MCVM. We obtained a precise three-dimensional distribution of brain, which offered doctors and researchers quantitative volume data and detailed morphological characterization for personal precise medicine of Cerebral atrophy/expansion. We hope this technique can bring convenience to visualization medical and personalized medicine.

  7. Accelerated spike resampling for accurate multiple testing controls.

    PubMed

    Harrison, Matthew T

    2013-02-01

    Controlling for multiple hypothesis tests using standard spike resampling techniques often requires prohibitive amounts of computation. Importance sampling techniques can be used to accelerate the computation. The general theory is presented, along with specific examples for testing differences across conditions using permutation tests and for testing pairwise synchrony and precise lagged-correlation between many simultaneously recorded spike trains using interval jitter.

  8. Which Fields Need Precision Nitrogen Management the Most?

    USDA-ARS?s Scientific Manuscript database

    Precision agriculture (PA) technologies used for identifying and managing within-field variability are not widely used despite decades of advancement. Many producers are hesitant to adopt PA because uncertainty exists about field-specific performance or the potential return on investment. These con...

  9. A Police and Insurance Joint Management System Based on High Precision BDS/GPS Positioning

    PubMed Central

    Zuo, Wenwei; Guo, Chi; Liu, Jingnan; Peng, Xuan; Yang, Min

    2018-01-01

    Car ownership in China reached 194 million vehicles at the end of 2016. The traffic congestion index (TCI) exceeds 2.0 during rush hour in some cities. Inefficient processing for minor traffic accidents is considered to be one of the leading causes for road traffic jams. Meanwhile, the process after an accident is quite troublesome. The main reason is that it is almost always impossible to get the complete chain of evidence when the accident happens. Accordingly, a police and insurance joint management system is developed which is based on high precision BeiDou Navigation Satellite System (BDS)/Global Positioning System (GPS) positioning to process traffic accidents. First of all, an intelligent vehicle rearview mirror terminal is developed. The terminal applies a commonly used consumer electronic device with single frequency navigation. Based on the high precision BDS/GPS positioning algorithm, its accuracy can reach sub-meter level in the urban areas. More specifically, a kernel driver is built to realize the high precision positioning algorithm in an Android HAL layer. Thus the third-party application developers can call the general location Application Programming Interface (API) of the original standard Global Navigation Satellite System (GNSS) to get high precision positioning results. Therefore, the terminal can provide lane level positioning service for car users. Next, a remote traffic accident processing platform is built to provide big data analysis and management. According to the big data analysis of information collected by BDS high precision intelligent sense service, vehicle behaviors can be obtained. The platform can also automatically match and screen the data that uploads after an accident to achieve accurate reproduction of the scene. Thus, it helps traffic police and insurance personnel to complete remote responsibility identification and survey for the accident. Thirdly, a rapid processing flow is established in this article to meet the

  10. A Police and Insurance Joint Management System Based on High Precision BDS/GPS Positioning.

    PubMed

    Zuo, Wenwei; Guo, Chi; Liu, Jingnan; Peng, Xuan; Yang, Min

    2018-01-10

    Car ownership in China reached 194 million vehicles at the end of 2016. The traffic congestion index (TCI) exceeds 2.0 during rush hour in some cities. Inefficient processing for minor traffic accidents is considered to be one of the leading causes for road traffic jams. Meanwhile, the process after an accident is quite troublesome. The main reason is that it is almost always impossible to get the complete chain of evidence when the accident happens. Accordingly, a police and insurance joint management system is developed which is based on high precision BeiDou Navigation Satellite System (BDS)/Global Positioning System (GPS) positioning to process traffic accidents. First of all, an intelligent vehicle rearview mirror terminal is developed. The terminal applies a commonly used consumer electronic device with single frequency navigation. Based on the high precision BDS/GPS positioning algorithm, its accuracy can reach sub-meter level in the urban areas. More specifically, a kernel driver is built to realize the high precision positioning algorithm in an Android HAL layer. Thus the third-party application developers can call the general location Application Programming Interface (API) of the original standard Global Navigation Satellite System (GNSS) to get high precision positioning results. Therefore, the terminal can provide lane level positioning service for car users. Next, a remote traffic accident processing platform is built to provide big data analysis and management. According to the big data analysis of information collected by BDS high precision intelligent sense service, vehicle behaviors can be obtained. The platform can also automatically match and screen the data that uploads after an accident to achieve accurate reproduction of the scene. Thus, it helps traffic police and insurance personnel to complete remote responsibility identification and survey for the accident. Thirdly, a rapid processing flow is established in this article to meet the

  11. Precision medicine in myasthenia graves: begin from the data precision

    PubMed Central

    Hong, Yu; Xie, Yanchen; Hao, Hong-Jun; Sun, Ren-Cheng

    2016-01-01

    Myasthenia gravis (MG) is a prototypic autoimmune disease with overt clinical and immunological heterogeneity. The data of MG is far from individually precise now, partially due to the rarity and heterogeneity of this disease. In this review, we provide the basic insights of MG data precision, including onset age, presenting symptoms, generalization, thymus status, pathogenic autoantibodies, muscle involvement, severity and response to treatment based on references and our previous studies. Subgroups and quantitative traits of MG are discussed in the sense of data precision. The role of disease registries and scientific bases of precise analysis are also discussed to ensure better collection and analysis of MG data. PMID:27127759

  12. Precise attitude control of the Stanford relativity satellite.

    NASA Technical Reports Server (NTRS)

    Bull, J. S.; Debra, D. B.

    1973-01-01

    A satellite being designed by the Stanford University to measure (with extremely high precision) the effect of General Relativity is described. Specifically, the satellite will measure two relativistic precessions predicted by the theory: the geodetic effect (6.9 arcsec/yr), due solely to motion about the earth, and the motional effect (0.05 arcsec/yr), due to rotation of the earth. The gyro design requirements, including the requirement for precise attitude control and a dynamic model for attitude control synthesis, are discussed. Closed loop simulation of the satellite's natural dynamics on an analog computer is described.

  13. Precise attitude rate estimation using star images obtained by mission telescope for satellite missions

    NASA Astrophysics Data System (ADS)

    Inamori, Takaya; Hosonuma, Takayuki; Ikari, Satoshi; Saisutjarit, Phongsatorn; Sako, Nobutada; Nakasuka, Shinichi

    2015-02-01

    Recently, small satellites have been employed in various satellite missions such as astronomical observation and remote sensing. During these missions, the attitudes of small satellites should be stabilized to a higher accuracy to obtain accurate science data and images. To achieve precise attitude stabilization, these small satellites should estimate their attitude rate under the strict constraints of mass, space, and cost. This research presents a new method for small satellites to precisely estimate angular rate using star blurred images by employing a mission telescope to achieve precise attitude stabilization. In this method, the angular velocity is estimated by assessing the quality of a star image, based on how blurred it appears to be. Because the proposed method utilizes existing mission devices, a satellite does not require additional precise rate sensors, which makes it easier to achieve precise stabilization given the strict constraints possessed by small satellites. The research studied the relationship between estimation accuracy and parameters used to achieve an attitude rate estimation, which has a precision greater than 1 × 10-6 rad/s. The method can be applied to all attitude sensors, which use optics systems such as sun sensors and star trackers (STTs). Finally, the method is applied to the nano astrometry satellite Nano-JASMINE, and we investigate the problems that are expected to arise with real small satellites by performing numerical simulations.

  14. An Era of Precision Astrophysics for Exoplanets, Stars, and the Milky Way

    NASA Astrophysics Data System (ADS)

    Stassun, Keivan G.; Kilodegree Extremely Little Telescope (KELT); Transiting Exoplanet Survey Satellite (TESS); Sloan Digital Sky Survey (SDSS)

    2018-06-01

    While observing stars teaches us about the physical properties of the stars themselves, that knowledge also is the key to measuring the properties of nearly all exoplanets, and also the history of the Galaxy. Combining data from current and upcoming all-sky surveys, including Gaia, TESS, and the fifth Sloan Digital Sky Survey (SDSS-V), will enable accurate, empirical measurements of fundamental properties for millions of stars throughout the Milky Way—including an increase by four orders of magnitude in the number of stars with reliable parallaxes, two orders of magnitude in the number with ultraprecise light curves, and two orders of magnitude in the number with detailed chemical abundances. We demonstrate that stellar masses, radii, temperatures, distances, space motions, and detailed chemical abundances can now be measured with precisions of order 1%, and with systematics better than ∼5% in most cases. We discuss the transformational advances that such precise stellar measurements promise for exoplanet science, including studies of planetary system architectures, forensic analyses of planet evolution pathways, testing planet formation theories, and even efforts to infer the mineralogy of planets. We also discuss the similarly transformational advances at hand for Galactic archaeology, including studies of stellar micro-populations, testing theories of star formation and of galaxy assembly, and even efforts to trace the chemical "family tree" of the Galaxy through stellar phylogenics. Finally, we discuss the revolution in stellar astrophysics represented by ultraprecise light curves of stars, specifically as probes of stellar interiors and therefore as stress-tests of stellar theory across the Hertzsprung-Russell diagram.

  15. Precision Distances with the Tip of the Red Giant Branch Method

    NASA Astrophysics Data System (ADS)

    Beaton, Rachael Lynn; Carnegie-Chicago Hubble Program Team

    2018-01-01

    The Carnegie-Chicago Hubble Program aims to construct a distance ladder that utilizes old stellar populations in the outskirts of galaxies to produce a high precision measurement of the Hubble Constant that is independent of Cepheids. The CCHP uses the tip of the red giant branch (TRGB) method, which is a statistical measurement technique that utilizes the termination of the red giant branch. Two innovations combine to make the TRGB a competitive route to the Hubble Constant (i) the large-scale measurement of trigonometric parallax by the Gaia mission and (ii) the development of both precise and accurate means of determining the TRGB in both nearby (~1 Mpc) and distant (~20 Mpc) galaxies. Here I will summarize our progress in developing these standardized techniques, focusing on both our edge-detection algorithm and our field selection strategy. Using these methods, the CCHP has determined equally precise (~2%) distances to galaxies in the Local Group (< 1 Mpc) and across the Local Volume (< 20 Mpc). The TRGB is, thus, an incredibly powerful and straightforward means to determine distances to galaxies of any Hubble Type and, thus, has enormous potential for putting any number of astrophyiscal phenomena on absolute units.

  16. Influence of Time-Pickoff Circuit Parameters on LiDAR Range Precision

    PubMed Central

    Wang, Hongming; Yang, Bingwei; Huyan, Jiayue; Xu, Lijun

    2017-01-01

    A pulsed time-of-flight (TOF) measurement-based Light Detection and Ranging (LiDAR) system is more effective for medium-long range distances. As a key ranging unit, a time-pickoff circuit based on automatic gain control (AGC) and constant fraction discriminator (CFD) is designed to reduce the walk error and the timing jitter for obtaining the accurate time interval. Compared with Cramer–Rao lower bound (CRLB) and the estimation of the timing jitter, four parameters-based Monte Carlo simulations are established to show how the range precision is influenced by the parameters, including pulse amplitude, pulse width, attenuation fraction and delay time of the CFD. Experiments were carried out to verify the relationship between the range precision and three of the parameters, exclusing pulse width. It can be concluded that two parameters of the ranging circuit (attenuation fraction and delay time) were selected according to the ranging performance of the minimum pulse amplitude. The attenuation fraction should be selected in the range from 0.2 to 0.6 to achieve high range precision. The selection criterion of the time-pickoff circuit parameters is helpful for the ranging circuit design of TOF LiDAR system. PMID:29039772

  17. Anatomically accurate individual face modeling.

    PubMed

    Zhang, Yu; Prakash, Edmond C; Sung, Eric

    2003-01-01

    This paper presents a new 3D face model of a specific person constructed from the anatomical perspective. By exploiting the laser range data, a 3D facial mesh precisely representing the skin geometry is reconstructed. Based on the geometric facial mesh, we develop a deformable multi-layer skin model. It takes into account the nonlinear stress-strain relationship and dynamically simulates the non-homogenous behavior of the real skin. The face model also incorporates a set of anatomically-motivated facial muscle actuators and underlying skull structure. Lagrangian mechanics governs the facial motion dynamics, dictating the dynamic deformation of facial skin in response to the muscle contraction.

  18. Bullet trajectory reconstruction - Methods, accuracy and precision.

    PubMed

    Mattijssen, Erwin J A T; Kerkhoff, Wim

    2016-05-01

    Based on the spatial relation between a primary and secondary bullet defect or on the shape and dimensions of the primary bullet defect, a bullet's trajectory prior to impact can be estimated for a shooting scene reconstruction. The accuracy and precision of the estimated trajectories will vary depending on variables such as, the applied method of reconstruction, the (true) angle of incidence, the properties of the target material and the properties of the bullet upon impact. This study focused on the accuracy and precision of estimated bullet trajectories when different variants of the probing method, ellipse method, and lead-in method are applied on bullet defects resulting from shots at various angles of incidence on drywall, MDF and sheet metal. The results show that in most situations the best performance (accuracy and precision) is seen when the probing method is applied. Only for the lowest angles of incidence the performance was better when either the ellipse or lead-in method was applied. The data provided in this paper can be used to select the appropriate method(s) for reconstruction and to correct for systematic errors (accuracy) and to provide a value of the precision, by means of a confidence interval of the specific measurement. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Toward optimizing patient-specific IMRT QA techniques in the accurate detection of dosimetrically acceptable and unacceptable patient plans

    PubMed Central

    McKenzie, Elizabeth M.; Balter, Peter A.; Stingo, Francesco C.; Jones, Jimmy; Followill, David S.; Kry, Stephen F.

    2014-01-01

    was no significant difference in the performance of any device between gamma criteria of 2%/2 mm, 3%/3 mm, and 5%/3 mm. Finally, optimal cutoffs (e.g., percent of pixels passing gamma) were determined for each device and while clinical practice commonly uses a threshold of 90% of pixels passing for most cases, these results showed variability in the optimal cutoff among devices. Conclusions: IMRT QA devices have differences in their ability to accurately detect dosimetrically acceptable and unacceptable plans. Field-by-field analysis with a MapCheck device and use of the MapCheck with a MapPhan phantom while delivering at planned rotational gantry angles resulted in a significantly poorer ability to accurately sort acceptable and unacceptable plans compared with the other techniques examined. Patient-specific IMRT QA techniques in general should be thoroughly evaluated for their ability to correctly differentiate acceptable and unacceptable plans. Additionally, optimal agreement thresholds should be identified and used as common clinical thresholds typically worked very poorly to identify unacceptable plans. PMID:25471949

  20. Toward optimizing patient-specific IMRT QA techniques in the accurate detection of dosimetrically acceptable and unacceptable patient plans.

    PubMed

    McKenzie, Elizabeth M; Balter, Peter A; Stingo, Francesco C; Jones, Jimmy; Followill, David S; Kry, Stephen F

    2014-12-01

    in the performance of any device between gamma criteria of 2%/2 mm, 3%/3 mm, and 5%/3 mm. Finally, optimal cutoffs (e.g., percent of pixels passing gamma) were determined for each device and while clinical practice commonly uses a threshold of 90% of pixels passing for most cases, these results showed variability in the optimal cutoff among devices. IMRT QA devices have differences in their ability to accurately detect dosimetrically acceptable and unacceptable plans. Field-by-field analysis with a MapCheck device and use of the MapCheck with a MapPhan phantom while delivering at planned rotational gantry angles resulted in a significantly poorer ability to accurately sort acceptable and unacceptable plans compared with the other techniques examined. Patient-specific IMRT QA techniques in general should be thoroughly evaluated for their ability to correctly differentiate acceptable and unacceptable plans. Additionally, optimal agreement thresholds should be identified and used as common clinical thresholds typically worked very poorly to identify unacceptable plans.

  1. Precision Control Module For UV Laser 3D Micromachining

    NASA Astrophysics Data System (ADS)

    Wu, Wen-Hong; Hung, Min-Wei; Chang, Chun-Li

    2011-01-01

    UV laser has been widely used in various micromachining such as micro-scribing or patterning processing. At present, most of the semiconductors, LEDs, photovoltaic solar panels and touch panels industries need the UV laser processing system. However, most of the UV laser processing applications in the industries utilize two dimensional (2D) plane processing. And there are tremendous business opportunities that can be developed, such as three dimensional (3D) structures of micro-electromechanical (MEMS) sensor or the precision depth control of indium tin oxide (ITO) thin films edge insulation in touch panels. This research aims to develop a UV laser 3D micromachining module that can create the novel applications for industries. By special designed beam expender in optical system, the focal point of UV laser can be adjusted quickly and accurately through the optical path control lens of laser beam expender optical system. Furthermore, the integrated software for galvanometric scanner and focal point adjustment mechanism is developed as well, so as to carry out the precise 3D microstructure machining.

  2. Precision Attitude Control for the BETTII Balloon-Borne Interferometer

    NASA Technical Reports Server (NTRS)

    Benford, Dominic J.; Fixsen, Dale J.; Rinehart. Stephen

    2012-01-01

    The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII) is an 8-meter baseline far-infrared interferometer to fly on a high altitude balloon. Operating at wavelengths of 30-90 microns, BETTII will obtain spatial and spectral information on science targets at angular resolutions down to less than half an arcsecond, a capability unmatched by other far-infrared facilities. This requires attitude control at a level ofless than a tenth of an arcsecond, a great challenge for a lightweight balloon-borne system. We have designed a precision attitude determination system to provide gondola attitude knowledge at a level of 2 milliarcseconds at rates up to 100Hz, with accurate absolute attitude determination at the half arcsecond level at rates of up to 10Hz. A mUlti-stage control system involving rigid body motion and tip-tilt-piston correction provides precision pointing stability to the level required for the far-infrared instrument to perform its spatial/spectral interferometry in an open-loop control. We present key aspects of the design of the attitude determination and control and its development status.

  3. The precision-recall plot is more informative than the ROC plot when evaluating binary classifiers on imbalanced datasets.

    PubMed

    Saito, Takaya; Rehmsmeier, Marc

    2015-01-01

    Binary classifiers are routinely evaluated with performance measures such as sensitivity and specificity, and performance is frequently illustrated with Receiver Operating Characteristics (ROC) plots. Alternative measures such as positive predictive value (PPV) and the associated Precision/Recall (PRC) plots are used less frequently. Many bioinformatics studies develop and evaluate classifiers that are to be applied to strongly imbalanced datasets in which the number of negatives outweighs the number of positives significantly. While ROC plots are visually appealing and provide an overview of a classifier's performance across a wide range of specificities, one can ask whether ROC plots could be misleading when applied in imbalanced classification scenarios. We show here that the visual interpretability of ROC plots in the context of imbalanced datasets can be deceptive with respect to conclusions about the reliability of classification performance, owing to an intuitive but wrong interpretation of specificity. PRC plots, on the other hand, can provide the viewer with an accurate prediction of future classification performance due to the fact that they evaluate the fraction of true positives among positive predictions. Our findings have potential implications for the interpretation of a large number of studies that use ROC plots on imbalanced datasets.

  4. Fully Nonlinear Modeling and Analysis of Precision Membranes

    NASA Technical Reports Server (NTRS)

    Pai, P. Frank; Young, Leyland G.

    2003-01-01

    High precision membranes are used in many current space applications. This paper presents a fully nonlinear membrane theory with forward and inverse analyses of high precision membrane structures. The fully nonlinear membrane theory is derived from Jaumann strains and stresses, exact coordinate transformations, the concept of local relative displacements, and orthogonal virtual rotations. In this theory, energy and Newtonian formulations are fully correlated, and every structural term can be interpreted in terms of vectors. Fully nonlinear ordinary differential equations (ODES) governing the large static deformations of known axisymmetric membranes under known axisymmetric loading (i.e., forward problems) are presented as first-order ODES, and a method for obtaining numerically exact solutions using the multiple shooting procedure is shown. A method for obtaining the undeformed geometry of any axisymmetric membrane with a known inflated geometry and a known internal pressure (i.e., inverse problems) is also derived. Numerical results from forward analysis are verified using results in the literature, and results from inverse analysis are verified using known exact solutions and solutions from the forward analysis. Results show that the membrane theory and the proposed numerical methods for solving nonlinear forward and inverse membrane problems are accurate.

  5. A real-time detector system for precise timing of audiovisual stimuli.

    PubMed

    Henelius, Andreas; Jagadeesan, Sharman; Huotilainen, Minna

    2012-01-01

    The successful recording of neurophysiologic signals, such as event-related potentials (ERPs) or event-related magnetic fields (ERFs), relies on precise information of stimulus presentation times. We have developed an accurate and flexible audiovisual sensor solution operating in real-time for on-line use in both auditory and visual ERP and ERF paradigms. The sensor functions independently of the used audio or video stimulus presentation tools or signal acquisition system. The sensor solution consists of two independent sensors; one for sound and one for light. The microcontroller-based audio sensor incorporates a novel approach to the detection of natural sounds such as multipart audio stimuli, using an adjustable dead time. This aids in producing exact markers for complex auditory stimuli and reduces the number of false detections. The analog photosensor circuit detects changes in light intensity on the screen and produces a marker for changes exceeding a threshold. The microcontroller software for the audio sensor is free and open source, allowing other researchers to customise the sensor for use in specific auditory ERP/ERF paradigms. The hardware schematics and software for the audiovisual sensor are freely available from the webpage of the authors' lab.

  6. A Method for Assessing the Accuracy of a Photogrammetry System for Precision Deployable Structures

    NASA Technical Reports Server (NTRS)

    Moore, Ashley

    2005-01-01

    The measurement techniques used to validate analytical models of large deployable structures are an integral Part of the technology development process and must be precise and accurate. Photogrammetry and videogrammetry are viable, accurate, and unobtrusive methods for measuring such large Structures. Photogrammetry uses Software to determine the three-dimensional position of a target using camera images. Videogrammetry is based on the same principle, except a series of timed images are analyzed. This work addresses the accuracy of a digital photogrammetry system used for measurement of large, deployable space structures at JPL. First, photogrammetry tests are performed on a precision space truss test article, and the images are processed using Photomodeler software. The accuracy of the Photomodeler results is determined through, comparison with measurements of the test article taken by an external testing group using the VSTARS photogrammetry system. These two measurements are then compared with Australis photogrammetry software that simulates a measurement test to predict its accuracy. The software is then used to study how particular factors, such as camera resolution and placement, affect the system accuracy to help design the setup for the videogrammetry system that will offer the highest level of accuracy for measurement of deploying structures.

  7. Precision studies of observables in $$p p \\rightarrow W \\rightarrow l\

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

    Alioli, S.; Arbuzov, A. B.; Bardin, D. Yu.

    This report was prepared in the context of the LPCC "Electroweak Precision Measurements at the LHC WG" and summarizes the activity of a subgroup dedicated to the systematic comparison of public Monte Carlo codes, which describe the Drell-Yan processes at hadron colliders, in particular at the CERN Large Hadron Collider (LHC). This work represents an important step towards the definition of an accurate simulation framework necessary for very high-precision measurements of electroweak (EW) observables such as the $W$ boson mass and the weak mixing angle. All the codes considered in this report share at least next-to-leading-order (NLO) accuracy in themore » prediction of the total cross sections in an expansion either in the strong or in the EW coupling constant. The NLO fixed-order predictions have been scrutinized at the technical level, using exactly the same inputs, setup and perturbative accuracy, in order to quantify the level of agreement of different implementations of the same calculation. A dedicated comparison, again at the technical level, of three codes that reach next-to-next-to-leading-order (NNLO) accuracy in quantum chromodynamics (QCD) for the total cross section has also been performed. These fixed-order results are a well-defined reference that allows a classification of the impact of higher-order sets of radiative corrections. Several examples of higher-order effects due to the strong or the EW interaction are discussed in this common framework. Also the combination of QCD and EW corrections is discussed, together with the ambiguities that affect the final result, due to the choice of a specific combination recipe.« less

  8. Precision studies of observables in $$p p \\rightarrow W \\rightarrow l\

    DOE PAGES

    Alioli, S.; Arbuzov, A. B.; Bardin, D. Yu.; ...

    2017-05-03

    This report was prepared in the context of the LPCC "Electroweak Precision Measurements at the LHC WG" and summarizes the activity of a subgroup dedicated to the systematic comparison of public Monte Carlo codes, which describe the Drell-Yan processes at hadron colliders, in particular at the CERN Large Hadron Collider (LHC). This work represents an important step towards the definition of an accurate simulation framework necessary for very high-precision measurements of electroweak (EW) observables such as the $W$ boson mass and the weak mixing angle. All the codes considered in this report share at least next-to-leading-order (NLO) accuracy in themore » prediction of the total cross sections in an expansion either in the strong or in the EW coupling constant. The NLO fixed-order predictions have been scrutinized at the technical level, using exactly the same inputs, setup and perturbative accuracy, in order to quantify the level of agreement of different implementations of the same calculation. A dedicated comparison, again at the technical level, of three codes that reach next-to-next-to-leading-order (NNLO) accuracy in quantum chromodynamics (QCD) for the total cross section has also been performed. These fixed-order results are a well-defined reference that allows a classification of the impact of higher-order sets of radiative corrections. Several examples of higher-order effects due to the strong or the EW interaction are discussed in this common framework. Also the combination of QCD and EW corrections is discussed, together with the ambiguities that affect the final result, due to the choice of a specific combination recipe.« less

  9. On the accurate estimation of gap fraction during daytime with digital cover photography

    NASA Astrophysics Data System (ADS)

    Hwang, Y. R.; Ryu, Y.; Kimm, H.; Macfarlane, C.; Lang, M.; Sonnentag, O.

    2015-12-01

    Digital cover photography (DCP) has emerged as an indirect method to obtain gap fraction accurately. Thus far, however, the intervention of subjectivity, such as determining the camera relative exposure value (REV) and threshold in the histogram, hindered computing accurate gap fraction. Here we propose a novel method that enables us to measure gap fraction accurately during daytime under various sky conditions by DCP. The novel method computes gap fraction using a single DCP unsaturated raw image which is corrected for scattering effects by canopies and a reconstructed sky image from the raw format image. To test the sensitivity of the novel method derived gap fraction to diverse REVs, solar zenith angles and canopy structures, we took photos in one hour interval between sunrise to midday under dense and sparse canopies with REV 0 to -5. The novel method showed little variation of gap fraction across different REVs in both dense and spares canopies across diverse range of solar zenith angles. The perforated panel experiment, which was used to test the accuracy of the estimated gap fraction, confirmed that the novel method resulted in the accurate and consistent gap fractions across different hole sizes, gap fractions and solar zenith angles. These findings highlight that the novel method opens new opportunities to estimate gap fraction accurately during daytime from sparse to dense canopies, which will be useful in monitoring LAI precisely and validating satellite remote sensing LAI products efficiently.

  10. Molecular diagnosis and precision medicine in allergy management.

    PubMed

    Riccio, Anna Maria; De Ferrari, Laura; Chiappori, Alessandra; Ledda, Sabina; Passalacqua, Giovanni; Melioli, Giovanni; Canonica, Giorgio Walter

    2016-11-01

    Precision medicine (PM) can be defined as a structural model aimed at customizing healthcare, with medical decisions/products tailored on an individual patient at a highly detailed level. In this sense, allergy diagnostics based on molecular allergen components allows to accurately define the patient's IgE repertoire. The availability of highly specialized singleplexed and multiplexed platforms support allergists with an advanced diagnostic armamentarium. The therapeutic intervention, driven by the standard diagnostic approach, but further supported by these innovative tools may result, for instance, in a more appropriate prescription of allergen immunotherapy (AIT). Also, the phenotyping of patients, which may have relevant effects on the treatment strategy, could be take advantage by the molecular allergy diagnosis.

  11. Precision Medicine Approaches to Diabetic Kidney Disease: Tissue as an Issue.

    PubMed

    Gluck, Caroline; Ko, Yi-An; Susztak, Katalin

    2017-05-01

    Precision medicine approaches, that tailor medications to specific individuals has made paradigm-shifting improvements for patients with certain cancer types. Such approaches, however, have not been implemented for patients with diabetic kidney disease. Precision medicine could offer new avenues for novel diagnostic, prognostic and targeted therapeutics development. Genetic studies associated with multiscalar omics datasets from tissue and cell types of interest of well-characterized cohorts are needed to change the current paradigm. In this review, we will discuss precision medicine approaches that the nephrology community can take to analyze tissue samples to develop new therapeutics for patients with diabetic kidney disease.

  12. A primer on precision medicine informatics.

    PubMed

    Sboner, Andrea; Elemento, Olivier

    2016-01-01

    In this review, we describe key components of a computational infrastructure for a precision medicine program that is based on clinical-grade genomic sequencing. Specific aspects covered in this review include software components and hardware infrastructure, reporting, integration into Electronic Health Records for routine clinical use and regulatory aspects. We emphasize informatics components related to reproducibility and reliability in genomic testing, regulatory compliance, traceability and documentation of processes, integration into clinical workflows, privacy requirements, prioritization and interpretation of results to report based on clinical needs, rapidly evolving knowledge base of genomic alterations and clinical treatments and return of results in a timely and predictable fashion. We also seek to differentiate between the use of precision medicine in germline and cancer. © The Author 2015. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  13. Can cancer researchers accurately judge whether preclinical reports will reproduce?

    PubMed Central

    Mandel, David R.; Kimmelman, Jonathan

    2017-01-01

    There is vigorous debate about the reproducibility of research findings in cancer biology. Whether scientists can accurately assess which experiments will reproduce original findings is important to determining the pace at which science self-corrects. We collected forecasts from basic and preclinical cancer researchers on the first 6 replication studies conducted by the Reproducibility Project: Cancer Biology (RP:CB) to assess the accuracy of expert judgments on specific replication outcomes. On average, researchers forecasted a 75% probability of replicating the statistical significance and a 50% probability of replicating the effect size, yet none of these studies successfully replicated on either criterion (for the 5 studies with results reported). Accuracy was related to expertise: experts with higher h-indices were more accurate, whereas experts with more topic-specific expertise were less accurate. Our findings suggest that experts, especially those with specialized knowledge, were overconfident about the RP:CB replicating individual experiments within published reports; researcher optimism likely reflects a combination of overestimating the validity of original studies and underestimating the difficulties of repeating their methodologies. PMID:28662052

  14. Developing precision medicine for people of East Asian descent.

    PubMed

    McAllister, Stacy L; Sun, Katherine; Gross, Eric R

    2016-11-11

    The goal of precision medicine is to separate patient populations into groups to ultimately provide customized care tailored to patients. In terms of precision medicine, ~540 million people in the world have a genetic variant of the aldehyde dehydrogenase 2 (ALDH2) enzyme causing a flushing response and tachycardia after alcohol consumption. The genetic variant is identified as ALDH2*2 and originates from East Asian descendants of the Han Chinese. The variant is particularly important to consider when discussing lifestyle choices with patients in terms of risk for developing specific diseases, preventative screening, and selection of medications for treatment. Here we provide examples why patients with an ALDH2*2 variant need more individualized medical management which is becoming a more standard practice in the precision medicine era.

  15. A new, high-precision measurement of the X-ray Cu K α spectrum

    NASA Astrophysics Data System (ADS)

    Mendenhall, Marcus H.; Cline, James P.; Henins, Albert; Hudson, Lawrence T.; Szabo, Csilla I.; Windover, Donald

    2016-03-01

    One of the primary measurement issues addressed with NIST Standard Reference Materials (SRMs) for powder diffraction is that of line position. SRMs for this purpose are certified with respect to lattice parameter, traceable to the SI through precise measurement of the emission spectrum of the X-ray source. Therefore, accurate characterization of the emission spectrum is critical to a minimization of the error bounds on the certified parameters. The presently accepted sources for the SI traceable characterization of the Cu K α emission spectrum are those of Härtwig, Hölzer et al., published in the 1990s. The structure of the X-ray emission lines of the Cu K α complex has been remeasured on a newly commissioned double-crystal instrument, with six-bounce Si (440) optics, in a manner directly traceable to the SI definition of the meter. In this measurement, the entire region from 8020 eV to 8100 eV has been covered with a highly precise angular scale and well-defined system efficiency, providing accurate wavelengths and relative intensities. This measurement is in modest disagreement with reference values for the wavelength of the Kα1 line, and strong disagreement for the wavelength of the Kα2 line.

  16. E/N effects on K0 values revealed by high precision measurements under low field conditions

    NASA Astrophysics Data System (ADS)

    Hauck, Brian C.; Siems, William F.; Harden, Charles S.; McHugh, Vincent M.; Hill, Herbert H.

    2016-07-01

    Ion mobility spectrometry (IMS) is used to detect chemical warfare agents, explosives, and narcotics. While IMS has a low rate of false positives, their occurrence causes the loss of time and money as the alarm is verified. Because numerous variables affect the reduced mobility (K0) of an ion, wide detection windows are required in order to ensure a low false negative response rate. Wide detection windows, however, reduce response selectivity, and interferents with similar K0 values may be mistaken for targeted compounds and trigger a false positive alarm. Detection windows could be narrowed if reference K0 values were accurately known for specific instrumental conditions. Unfortunately, there is a lack of confidence in the literature values due to discrepancies in the reported K0 values and their lack of reported error. This creates the need for the accurate control and measurement of each variable affecting ion mobility, as well as for a central accurate IMS database for reference and calibration. A new ion mobility spectrometer has been built that reduces the error of measurements affecting K0 by an order of magnitude less than ±0.2%. Precise measurements of ±0.002 cm2 V-1 s-1 or better have been produced and, as a result, an unexpected relationship between K0 and the electric field to number density ratio (E/N) has been discovered in which the K0 values of ions decreased as a function of E/N along a second degree polynomial trend line towards an apparent asymptote at approximately 4 Td.

  17. Precision mechatronics based on high-precision measuring and positioning systems and machines

    NASA Astrophysics Data System (ADS)

    Jäger, Gerd; Manske, Eberhard; Hausotte, Tino; Mastylo, Rostyslav; Dorozhovets, Natalja; Hofmann, Norbert

    2007-06-01

    Precision mechatronics is defined in the paper as the science and engineering of a new generation of high precision systems and machines. Nanomeasuring and nanopositioning engineering represents important fields of precision mechatronics. The nanometrology is described as the today's limit of the precision engineering. The problem, how to design nanopositioning machines with uncertainties as small as possible will be discussed. The integration of several optical and tactile nanoprobes makes the 3D-nanopositioning machine suitable for various tasks, such as long range scanning probe microscopy, mask and wafer inspection, nanotribology, nanoindentation, free form surface measurement as well as measurement of microoptics, precision molds, microgears, ring gauges and small holes.

  18. Computational Calorimetry: High-Precision Calculation of Host–Guest Binding Thermodynamics

    PubMed Central

    2015-01-01

    We present a strategy for carrying out high-precision calculations of binding free energy and binding enthalpy values from molecular dynamics simulations with explicit solvent. The approach is used to calculate the thermodynamic profiles for binding of nine small molecule guests to either the cucurbit[7]uril (CB7) or β-cyclodextrin (βCD) host. For these systems, calculations using commodity hardware can yield binding free energy and binding enthalpy values with a precision of ∼0.5 kcal/mol (95% CI) in a matter of days. Crucially, the self-consistency of the approach is established by calculating the binding enthalpy directly, via end point potential energy calculations, and indirectly, via the temperature dependence of the binding free energy, i.e., by the van’t Hoff equation. Excellent agreement between the direct and van’t Hoff methods is demonstrated for both host–guest systems and an ion-pair model system for which particularly well-converged results are attainable. Additionally, we find that hydrogen mass repartitioning allows marked acceleration of the calculations with no discernible cost in precision or accuracy. Finally, we provide guidance for accurately assessing numerical uncertainty of the results in settings where complex correlations in the time series can pose challenges to statistical analysis. The routine nature and high precision of these binding calculations opens the possibility of including measured binding thermodynamics as target data in force field optimization so that simulations may be used to reliably interpret experimental data and guide molecular design. PMID:26523125

  19. Precision Teaching.

    ERIC Educational Resources Information Center

    Couch, Richard W.

    Precision teaching (PT) is an approach to the science of human behavior that focuses on precise monitoring of carefully defined behaviors in an attempt to construct an environmental analysis of that behavior and its controlling variables. A variety of subjects have been used with PT, ranging in academic objectives from beginning reading to college…

  20. Glass ceramic ZERODUR enabling nanometer precision

    NASA Astrophysics Data System (ADS)

    Jedamzik, Ralf; Kunisch, Clemens; Nieder, Johannes; Westerhoff, Thomas

    2014-03-01

    The IC Lithography roadmap foresees manufacturing of devices with critical dimension of < 20 nm. Overlay specification of single digit nanometer asking for nanometer positioning accuracy requiring sub nanometer position measurement accuracy. The glass ceramic ZERODUR® is a well-established material in critical components of microlithography wafer stepper and offered with an extremely low coefficient of thermal expansion (CTE), the tightest tolerance available on market. SCHOTT is continuously improving manufacturing processes and it's method to measure and characterize the CTE behavior of ZERODUR® to full fill the ever tighter CTE specification for wafer stepper components. In this paper we present the ZERODUR® Lithography Roadmap on the CTE metrology and tolerance. Additionally, simulation calculations based on a physical model are presented predicting the long term CTE behavior of ZERODUR® components to optimize dimensional stability of precision positioning devices. CTE data of several low thermal expansion materials are compared regarding their temperature dependence between - 50°C and + 100°C. ZERODUR® TAILORED 22°C is full filling the tight CTE tolerance of +/- 10 ppb / K within the broadest temperature interval compared to all other materials of this investigation. The data presented in this paper explicitly demonstrates the capability of ZERODUR® to enable the nanometer precision required for future generation of lithography equipment and processes.

  1. Newborn Screening in the Era of Precision Medicine.

    PubMed

    Yang, Lan; Chen, Jiajia; Shen, Bairong

    2017-01-01

    As newborn screening success stories gained general confirmation during the past 50 years, scientists quickly discovered diagnostic tests for a host of genetic disorders that could be treated at birth. Outstanding progress in sequencing technologies over the last two decades has made it possible to comprehensively profile newborn screening (NBS) and identify clinically relevant genomic alterations. With the rapid developments in whole-genome sequencing (WGS) and whole-exome sequencing (WES) recently, we can detect newborns at the genomic level and be able to direct the appropriate diagnosis to the different individuals at the appropriate time, which is also encompassed in the concept of precision medicine. Besides, we can develop novel interventions directed at the molecular characteristics of genetic diseases in newborns. The implementation of genomics in NBS programs would provide an effective premise for the identification of the majority of genetic aberrations and primarily help in accurate guidance in treatment and better prediction. However, there are some debate correlated with the widespread application of genome sequencing in NBS due to some major concerns such as clinical analysis, result interpretation, storage of sequencing data, and communication of clinically relevant mutations to pediatricians and parents, along with the ethical, legal, and social implications (so-called ELSI). This review is focused on these critical issues and concerns about the expanding role of genomics in NBS for precision medicine. If WGS or WES is to be incorporated into NBS practice, considerations about these challenges should be carefully regarded and tackled properly to adapt the requirement of genome sequencing in the era of precision medicine.

  2. Precise documentation of well-structured programs

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

    Parnas, D.L.; Madey, J.; Iglewski, M.

    1997-11-01

    This paper describes a new form of program documentation that is precise, systematic and readable. This documentation comprises a set of displays supplemented by a lexicon and an index. Each display presents a program fragment in such a way that its correctness can be examined without looking at any other display. Each display has three parts: (1) the specification of the program presented in the display, (2) the program itself, and (3) the specifications of programs invoked by this program. The displays are intended to be used by Software Engineers as a reference document during inspection and maintenance. This papermore » also introduces a specification technique that is a refinement of Mills functional approach to program documentation and verification; programs are specified and described in tabular form.« less

  3. Accurate Cell Division in Bacteria: How Does a Bacterium Know Where its Middle Is?

    NASA Astrophysics Data System (ADS)

    Howard, Martin; Rutenberg, Andrew

    2004-03-01

    I will discuss the physical principles lying behind the acquisition of accurate positional information in bacteria. A good application of these ideas is to the rod-shaped bacterium E. coli which divides precisely at its cellular midplane. This positioning is controlled by the Min system of proteins. These proteins coherently oscillate from end to end of the bacterium. I will present a reaction-diffusion model that describes the diffusion of the Min proteins, and their binding/unbinding from the cell membrane. The system possesses an instability that spontaneously generates the Min oscillations, which control accurate placement of the midcell division site. I will then discuss the role of fluctuations in protein dynamics, and investigate whether fluctuations set optimal protein concentration levels. Finally I will examine cell division in a different bacteria, B. subtilis. where different physical principles are used to regulate accurate cell division. See: Howard, Rutenberg, de Vet: Dynamic compartmentalization of bacteria: accurate division in E. coli. Phys. Rev. Lett. 87 278102 (2001). Howard, Rutenberg: Pattern formation inside bacteria: fluctuations due to the low copy number of proteins. Phys. Rev. Lett. 90 128102 (2003). Howard: A mechanism for polar protein localization in bacteria. J. Mol. Biol. 335 655-663 (2004).

  4. Accurate Detection of Dysmorphic Nuclei Using Dynamic Programming and Supervised Classification.

    PubMed

    Verschuuren, Marlies; De Vylder, Jonas; Catrysse, Hannes; Robijns, Joke; Philips, Wilfried; De Vos, Winnok H

    2017-01-01

    A vast array of pathologies is typified by the presence of nuclei with an abnormal morphology. Dysmorphic nuclear phenotypes feature dramatic size changes or foldings, but also entail much subtler deviations such as nuclear protrusions called blebs. Due to their unpredictable size, shape and intensity, dysmorphic nuclei are often not accurately detected in standard image analysis routines. To enable accurate detection of dysmorphic nuclei in confocal and widefield fluorescence microscopy images, we have developed an automated segmentation algorithm, called Blebbed Nuclei Detector (BleND), which relies on two-pass thresholding for initial nuclear contour detection, and an optimal path finding algorithm, based on dynamic programming, for refining these contours. Using a robust error metric, we show that our method matches manual segmentation in terms of precision and outperforms state-of-the-art nuclear segmentation methods. Its high performance allowed for building and integrating a robust classifier that recognizes dysmorphic nuclei with an accuracy above 95%. The combined segmentation-classification routine is bound to facilitate nucleus-based diagnostics and enable real-time recognition of dysmorphic nuclei in intelligent microscopy workflows.

  5. Accurate Detection of Dysmorphic Nuclei Using Dynamic Programming and Supervised Classification

    PubMed Central

    Verschuuren, Marlies; De Vylder, Jonas; Catrysse, Hannes; Robijns, Joke; Philips, Wilfried

    2017-01-01

    A vast array of pathologies is typified by the presence of nuclei with an abnormal morphology. Dysmorphic nuclear phenotypes feature dramatic size changes or foldings, but also entail much subtler deviations such as nuclear protrusions called blebs. Due to their unpredictable size, shape and intensity, dysmorphic nuclei are often not accurately detected in standard image analysis routines. To enable accurate detection of dysmorphic nuclei in confocal and widefield fluorescence microscopy images, we have developed an automated segmentation algorithm, called Blebbed Nuclei Detector (BleND), which relies on two-pass thresholding for initial nuclear contour detection, and an optimal path finding algorithm, based on dynamic programming, for refining these contours. Using a robust error metric, we show that our method matches manual segmentation in terms of precision and outperforms state-of-the-art nuclear segmentation methods. Its high performance allowed for building and integrating a robust classifier that recognizes dysmorphic nuclei with an accuracy above 95%. The combined segmentation-classification routine is bound to facilitate nucleus-based diagnostics and enable real-time recognition of dysmorphic nuclei in intelligent microscopy workflows. PMID:28125723

  6. Creation of an idealized nasopharynx geometry for accurate computational fluid dynamics simulations of nasal airflow in patient-specific models lacking the nasopharynx anatomy

    PubMed Central

    Borojeni, Azadeh A.T.; Frank-Ito, Dennis O.; Kimbell, Julia S.; Rhee, John S.; Garcia, Guilherme J. M.

    2016-01-01

    Virtual surgery planning based on computational fluid dynamics (CFD) simulations has the potential to improve surgical outcomes for nasal airway obstruction (NAO) patients, but the benefits of virtual surgery planning must outweigh the risks of radiation exposure. Cone beam computed tomography (CBCT) scans represent an attractive imaging modality for virtual surgery planning due to lower costs and lower radiation exposures compared with conventional CT scans. However, to minimize the radiation exposure, the CBCT sinusitis protocol sometimes images only the nasal cavity, excluding the nasopharynx. The goal of this study was to develop an idealized nasopharynx geometry for accurate representation of outlet boundary conditions when the nasopharynx geometry is unavailable. Anatomically-accurate models of the nasopharynx created from thirty CT scans were intersected with planes rotated at different angles to obtain an average geometry. Cross sections of the idealized nasopharynx were approximated as ellipses with cross-sectional areas and aspect ratios equal to the average in the actual patient-specific models. CFD simulations were performed to investigate whether nasal airflow patterns were affected when the CT-based nasopharynx was replaced by the idealized nasopharynx in 10 NAO patients. Despite the simple form of the idealized geometry, all biophysical variables (nasal resistance, airflow rate, and heat fluxes) were very similar in the idealized vs. patient-specific models. The results confirmed the expectation that the nasopharynx geometry has a minimal effect in the nasal airflow patterns during inspiration. The idealized nasopharynx geometry will be useful in future CFD studies of nasal airflow based on medical images that exclude the nasopharynx. PMID:27525807

  7. Precision positioning device

    DOEpatents

    McInroy, John E.

    2005-01-18

    A precision positioning device is provided. The precision positioning device comprises a precision measuring/vibration isolation mechanism. A first plate is provided with the precision measuring mean secured to the first plate. A second plate is secured to the first plate. A third plate is secured to the second plate with the first plate being positioned between the second plate and the third plate. A fourth plate is secured to the third plate with the second plate being positioned between the third plate and the fourth plate. An adjusting mechanism for adjusting the position of the first plate, the second plate, the third plate, and the fourth plate relative to each other.

  8. Search Filter Precision Can Be Improved By NOTing Out Irrelevant Content

    PubMed Central

    Wilczynski, Nancy L.; McKibbon, K. Ann; Haynes, R. Brian

    2011-01-01

    Background: Most methodologic search filters developed for use in large electronic databases such as MEDLINE have low precision. One method that has been proposed but not tested for improving precision is NOTing out irrelevant content. Objective: To determine if search filter precision can be improved by NOTing out the text words and index terms assigned to those articles that are retrieved but are off-target. Design: Analytic survey. Methods: NOTing out unique terms in off-target articles and testing search filter performance in the Clinical Hedges Database. Main Outcome Measures: Sensitivity, specificity, precision and number needed to read (NNR). Results: For all purpose categories (diagnosis, prognosis and etiology) except treatment and for all databases (MEDLINE, EMBASE, CINAHL and PsycINFO), constructing search filters that NOTed out irrelevant content resulted in substantive improvements in NNR (over four-fold for some purpose categories and databases). Conclusion: Search filter precision can be improved by NOTing out irrelevant content. PMID:22195215

  9. Precision medicine in breast cancer: reality or utopia?

    PubMed

    Bettaieb, Ali; Paul, Catherine; Plenchette, Stéphanie; Shan, Jingxuan; Chouchane, Lotfi; Ghiringhelli, François

    2017-06-17

    Many cancers, including breast cancer, have demonstrated prognosis and support advantages thanks to the discovery of targeted therapies. The advent of these new approaches marked the rise of precision medicine, which leads to improve the diagnosis, prognosis and treatment of cancer. Precision medicine takes into account the molecular and biological specificities of the patient and their tumors that will influence the treatment determined by physicians. This new era of medicine is accessible through molecular genetics platforms, the development of high-speed sequencers and means of analysis of these data. Despite the spectacular results in the treatment of cancers including breast cancer, described in this review, not all patients however can benefit from this new strategy. This seems to be related to the many genetic mutations, which may be different from one patient to another or within the same patient. It comes to give new impetus to the research-both from a technological and biological point of view-to make the hope of precision medicine accessible to all.

  10. Rapid and precise determination of total sulphur in soda-lime-silica glasses.

    PubMed

    Beesley, W J; Chamberlain, B R

    1974-04-01

    A method is described for the determination of total sulphur in small amounts of soda-lime-silica glasses (100 mg or less). The crushed glass is mixed with vanadium pentoxide and decomposed at 1450 degrees under oxygen. The sulphur is quantitatively removed from the glass and determined by a conductometric technique. The method is standardized by accurately injecting sulphur dioxide into the furnace tube. The analysis time is about 10 min and the overall precision (2s) is of the order of 5%.

  11. Developing and implementing a high precision setup system

    NASA Astrophysics Data System (ADS)

    Peng, Lee-Cheng

    The demand for high-precision radiotherapy (HPRT) was first implemented in stereotactic radiosurgery using a rigid, invasive stereotactic head frame. Fractionated stereotactic radiotherapy (SRT) with a frameless device was developed along a growing interest in sophisticated treatment with a tight margin and high-dose gradient. This dissertation establishes the complete management for HPRT in the process of frameless SRT, including image-guided localization, immobilization, and dose evaluation. The most ideal and precise positioning system can allow for ease of relocation, real-time patient movement assessment, high accuracy, and no additional dose in daily use. A new image-guided stereotactic positioning system (IGSPS), the Align RT3C 3D surface camera system (ART, VisionRT), which combines 3D surface images and uses a real-time tracking technique, was developed to ensure accurate positioning at the first place. The uncertainties of current optical tracking system, which causes patient discomfort due to additional bite plates using the dental impression technique and external markers, are found. The accuracy and feasibility of ART is validated by comparisons with the optical tracking and cone-beam computed tomography (CBCT) systems. Additionally, an effective daily quality assurance (QA) program for the linear accelerator and multiple IGSPSs is the most important factor to ensure system performance in daily use. Currently, systematic errors from the phantom variety and long measurement time caused by switching phantoms were discovered. We investigated the use of a commercially available daily QA device to improve the efficiency and thoroughness. Reasonable action level has been established by considering dosimetric relevance and clinic flow. As for intricate treatments, the effect of dose deviation caused by setup errors remains uncertain on tumor coverage and toxicity on OARs. The lack of adequate dosimetric simulations based on the true treatment coordinates from

  12. LAI-2000 Accuracy, Precision, and Application to Visual Estimation of Leaf Area Index of Loblolly Pine

    Treesearch

    Jason A. Gatch; Timothy B. Harrington; James P. Castleberry

    2002-01-01

    Leaf area index (LAI) is an important parameter of forest stand productivity that has been used to diagnose stand vigor and potential fertilizer response of southern pines. The LAI-2000 was tested for its ability to provide accurate and precise estimates of LAI of loblolly pine (Pinus taeda L.). To test instrument accuracy, regression was used to...

  13. An Accurate Co-registration Method for Airborne Repeat-pass InSAR

    NASA Astrophysics Data System (ADS)

    Dong, X. T.; Zhao, Y. H.; Yue, X. J.; Han, C. M.

    2017-10-01

    Interferometric Synthetic Aperture Radar (InSAR) technology plays a significant role in topographic mapping and surface deformation detection. Comparing with spaceborne repeat-pass InSAR, airborne repeat-pass InSAR solves the problems of long revisit time and low-resolution images. Due to the advantages of flexible, accurate, and fast obtaining abundant information, airborne repeat-pass InSAR is significant in deformation monitoring of shallow ground. In order to getting precise ground elevation information and interferometric coherence of deformation monitoring from master and slave images, accurate co-registration must be promised. Because of side looking, repeat observing path and long baseline, there are very different initial slant ranges and flight heights between repeat flight paths. The differences of initial slant ranges and flight height lead to the pixels, located identical coordinates on master and slave images, correspond to different size of ground resolution cells. The mismatching phenomenon performs very obvious on the long slant range parts of master image and slave image. In order to resolving the different sizes of pixels and getting accurate co-registration results, a new method is proposed based on Range-Doppler (RD) imaging model. VV-Polarization C-band airborne repeat-pass InSAR images were used in experiment. The experiment result shows that the proposed method leads to superior co-registration accuracy.

  14. High-precision measurement of the X-ray Cu Kα spectrum

    PubMed Central

    Mendenhall, Marcus H.; Henins, Albert; Hudson, Lawrence T.; Szabo, Csilla I.; Windover, Donald; Cline, James P.

    2017-01-01

    The structure of the X-ray emission lines of the Cu Kα complex has been remeasured on a newly commissioned instrument, in a manner directly traceable to the Système Internationale definition of the meter. In this measurement, the region from 8000 eV to 8100 eV has been covered with a highly precise angular scale, and well-defined system efficiency, providing accurate wavelengths and relative intensities. This measurement updates the standard multi-Lorentzian-fit parameters from Härtwig, Hölzer, et al., and is in modest disagreement with their results for the wavelength of the Kα1 line when compared via quadratic fitting of the peak top; the intensity ratio of Kα1 to Kα2 agrees within the combined error bounds. However, the position of the fitted top of Kα1 is very sensitive to the fit parameters, so it is not believed to be a robust value to quote without further qualification. We also provide accurate intensity and wavelength information for the so-called Kα3,4 “satellite” complex. Supplementary data is provided which gives the entire shape of the spectrum in this region, allowing it to be used directly in cases where simplified, multi-Lorentzian fits to it are not sufficiently accurate. PMID:28757682

  15. Research on precise modeling of buildings based on multi-source data fusion of air to ground

    NASA Astrophysics Data System (ADS)

    Li, Yongqiang; Niu, Lubiao; Yang, Shasha; Li, Lixue; Zhang, Xitong

    2016-03-01

    Aims at the accuracy problem of precise modeling of buildings, a test research was conducted based on multi-source data for buildings of the same test area , including top data of air-borne LiDAR, aerial orthophotos, and façade data of vehicle-borne LiDAR. After accurately extracted the top and bottom outlines of building clusters, a series of qualitative and quantitative analysis was carried out for the 2D interval between outlines. Research results provide a reliable accuracy support for precise modeling of buildings of air ground multi-source data fusion, on the same time, discussed some solution for key technical problems.

  16. An in-line micro-pyrolysis system to remove contaminating organic species for precise and accurate water isotope analysis by spectroscopic techniques

    NASA Astrophysics Data System (ADS)

    Panetta, R. J.; Hsiao, G.

    2011-12-01

    Trace levels of organic contaminants such as short alcohols and terpenoids have been shown to cause spectral interference in water isotope analysis by spectroscopic techniques. The result is degraded precision and accuracy in both δD and δ18O for samples such as beverages, plant extracts or slightly contaminated waters. An initial approach offered by manufacturers is post-processing software that analyzes spectral features to identify and flag contaminated samples. However, it is impossible for this software to accurately reconstruct the water isotope signature, thus it is primarily a metric for data quality. Here, we describe a novel in-line pyrolysis system (Micro-Pyrolysis Technology, MPT) placed just prior to the inlet of a cavity ring-down spectroscopy (CRDS) analyzer that effectively removes interfering organic molecules without altering the isotope values of the water. Following injection of the water sample, N2 carrier gas passes the sample through a micro-pyrolysis tube heated with multiple high temperature elements in an oxygen-free environment. The temperature is maintained above the thermal decomposition threshold of most organic compounds (≤ 900 oC), but well below that of water (~2000 oC). The main products of the pyrolysis reaction are non-interfering species such as elemental carbon and H2 gas. To test the efficacy and applicability of the system, waters of known isotopic composition were spiked with varying amounts of common interfering alcohols (methanol, ethanol, propanol, hexanol, trans-2-hexenol, cis-3-hexanol up to 5 % v/v) and common soluble plant terpenoids (carveol, linalool, geraniol, prenol). Spiked samples with no treatment to remove the organics show strong interfering absorption peaks that adversely affect the δD and δ18O values. However, with the MPT in place, all interfering absorption peaks are removed and the water absorption spectrum is fully restored. As a consequence, the δD and δ18O values also return to their original

  17. J-GFT NMR for precise measurement of mutually correlated nuclear spin-spin couplings.

    PubMed

    Atreya, Hanudatta S; Garcia, Erwin; Shen, Yang; Szyperski, Thomas

    2007-01-24

    G-matrix Fourier transform (GFT) NMR spectroscopy is presented for accurate and precise measurement of chemical shifts and nuclear spin-spin couplings correlated according to spin system. The new approach, named "J-GFT NMR", is based on a largely extended GFT NMR formalism and promises to have a broad impact on projection NMR spectroscopy. Specifically, constant-time J-GFT (6,2)D (HA-CA-CO)-N-HN was implemented for simultaneous measurement of five mutually correlated NMR parameters, that is, 15N backbone chemical shifts and the four one-bond spin-spin couplings 13Calpha-1Halpha, 13Calpha-13C', 15N-13C', and 15N-1HNu. The experiment was applied for measuring residual dipolar couplings (RDCs) in an 8 kDa protein Z-domain aligned with Pf1 phages. Comparison with RDC values extracted from conventional NMR experiments reveals that RDCs are measured with high precision and accuracy, which is attributable to the facts that (i) the use of constant time evolution ensures that signals do not broaden whenever multiple RDCs are jointly measured in a single dimension and (ii) RDCs are multiply encoded in the multiplets arising from the joint sampling. This corresponds to measuring the couplings multiple times in a statistically independent manner. A key feature of J-GFT NMR, i.e., the correlation of couplings according to spin systems without reference to sequential resonance assignments, promises to be particularly valuable for rapid identification of backbone conformation and classification of protein fold families on the basis of statistical analysis of dipolar couplings.

  18. Reliability, precision, and gender differences in knee internal/external rotation proprioception measurements.

    PubMed

    Nagai, Takashi; Sell, Timothy C; Abt, John P; Lephart, Scott M

    2012-11-01

    To develop and assess the reliability and precision of knee internal/external rotation (IR/ER) threshold to detect passive motion (TTDPM) and determine if gender differences exist. Test-retest for the reliability/precision and cross-sectional for gender comparisons. University neuromuscular and human performance research laboratory. Ten subjects for the reliability and precision aim. Twenty subjects (10 males and 10 females) for gender comparisons. All TTDPM tests were performed using a multi-mode dynamometer. Subjects performed TTDPM at two knee positions (near IR or ER end-range). Intraclass correlation coefficient (ICC (3,k)) and standard error of measurement (SEM) were used to evaluate the reliability and precision. Independent t-tests were used to compare genders. TTDPM toward IR and ER at two knee positions. Intrasession and intersession reliability and precision were good (ICC=0.68-0.86; SEM=0.22°-0.37°). Females had significantly diminished TTDPM toward IR at IR-test position (males: 0.77°±0.14°, females: 1.18°±0.46°, p=0.021) and TTDPM toward IR at the ER-test position (males: 0.87°±0.13°, females: 1.36°±0.58°, p=0.026). No other significant gender differences were found (p>0.05). The current IR/ER TTDPM methods are reliable and accurate for the test-retest or cross-section research design. Gender differences were found toward IR where the ACL acts as the secondary restraint. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. High channel count microphone array accurately and precisely localizes ultrasonic signals from freely-moving mice.

    PubMed

    Warren, Megan R; Sangiamo, Daniel T; Neunuebel, Joshua P

    2018-03-01

    An integral component in the assessment of vocal behavior in groups of freely interacting animals is the ability to determine which animal is producing each vocal signal. This process is facilitated by using microphone arrays with multiple channels. Here, we made important refinements to a state-of-the-art microphone array based system used to localize vocal signals produced by freely interacting laboratory mice. Key changes to the system included increasing the number of microphones as well as refining the methodology for localizing and assigning vocal signals to individual mice. We systematically demonstrate that the improvements in the methodology for localizing mouse vocal signals led to an increase in the number of signals detected as well as the number of signals accurately assigned to an animal. These changes facilitated the acquisition of larger and more comprehensive data sets that better represent the vocal activity within an experiment. Furthermore, this system will allow more thorough analyses of the role that vocal signals play in social communication. We expect that such advances will broaden our understanding of social communication deficits in mouse models of neurological disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. An Online Gravity Modeling Method Applied for High Precision Free-INS

    PubMed Central

    Wang, Jing; Yang, Gongliu; Li, Jing; Zhou, Xiao

    2016-01-01

    For real-time solution of inertial navigation system (INS), the high-degree spherical harmonic gravity model (SHM) is not applicable because of its time and space complexity, in which traditional normal gravity model (NGM) has been the dominant technique for gravity compensation. In this paper, a two-dimensional second-order polynomial model is derived from SHM according to the approximate linear characteristic of regional disturbing potential. Firstly, deflections of vertical (DOVs) on dense grids are calculated with SHM in an external computer. And then, the polynomial coefficients are obtained using these DOVs. To achieve global navigation, the coefficients and applicable region of polynomial model are both updated synchronously in above computer. Compared with high-degree SHM, the polynomial model takes less storage and computational time at the expense of minor precision. Meanwhile, the model is more accurate than NGM. Finally, numerical test and INS experiment show that the proposed method outperforms traditional gravity models applied for high precision free-INS. PMID:27669261

  1. An Online Gravity Modeling Method Applied for High Precision Free-INS.

    PubMed

    Wang, Jing; Yang, Gongliu; Li, Jing; Zhou, Xiao

    2016-09-23

    For real-time solution of inertial navigation system (INS), the high-degree spherical harmonic gravity model (SHM) is not applicable because of its time and space complexity, in which traditional normal gravity model (NGM) has been the dominant technique for gravity compensation. In this paper, a two-dimensional second-order polynomial model is derived from SHM according to the approximate linear characteristic of regional disturbing potential. Firstly, deflections of vertical (DOVs) on dense grids are calculated with SHM in an external computer. And then, the polynomial coefficients are obtained using these DOVs. To achieve global navigation, the coefficients and applicable region of polynomial model are both updated synchronously in above computer. Compared with high-degree SHM, the polynomial model takes less storage and computational time at the expense of minor precision. Meanwhile, the model is more accurate than NGM. Finally, numerical test and INS experiment show that the proposed method outperforms traditional gravity models applied for high precision free-INS.

  2. Thermoelectric technique to precisely control hyperthermic exposures of human whole blood.

    PubMed

    DuBose, D A; Langevin, R C; Morehouse, D H

    1996-12-01

    The need in military research to avoid exposing humans to harsh environments and reduce animal use requires the development of in vitro models for the study of hyperthermic injury. A thermoelectric module (TEM) system was employed to heat human whole blood (HWB) in a manner similar to that experienced by heat-stroked rats. This system precisely and accurately replicated mild, moderate, and extreme heat-stress exposures. Temperature changes could be monitored without the introduction of a test sample thermistor, which reduced contamination problems. HWB with hematocrits of 45 or 50% had similar heating curves, indicating that the system compensated for differences in sample character. The unit's size permitted its containment within a standard carbon dioxide incubator to further control sample environment. These results indicate that the TEM system can precisely control temperature change in this heat stress in vitro model employing HWB. Information obtained from such a model could contribute to military preparedness.

  3. Proceedings of the Fourth Precise Time and Time Interval Planning Meeting

    NASA Technical Reports Server (NTRS)

    Acrivos, H. N. (Compiler); Wardrip, S. C. (Compiler)

    1972-01-01

    The proceedings of a conference on Precise Time and Time Interval Planning are presented. The subjects discussed include the following: (1) satellite timing techniques, precision frequency sources, and very long baseline interferometry, (2) frequency stabilities and communications, and (3) very low frequency and ultrahigh frequency propagation and use. Emphasis is placed on the accuracy of time discrimination obtained with time measuring equipment and specific applications of time measurement to military operations and civilian research projects.

  4. Ultra-Light Precision Membrane Optics

    NASA Technical Reports Server (NTRS)

    Moore, Jim; Gunter, Kent; Patrick, Brian; Marty, Dave; Bates, Kevin; Gatlin, Romona; Clayton, Bill; Rood, Bob; Brantley, Whitt (Technical Monitor)

    2001-01-01

    SRS Technologies and NASA Marshall Space Flight Center have conducted a research effort to explore the possibility of developing ultra-lightweight membrane optics for future imaging applications. High precision optical flats and spherical mirrors were produced under this research effort. The thin film mirrors were manufactured using surface replication casting of CPI(Trademark), a polyimide material developed specifically for UV hardness and thermal stability. In the course of this program, numerous polyimide films were cast with surface finishes better than 1.5 nanometers rms and thickness variation of less than 63 nanometers. Precision membrane optical flats were manufactured demonstrating better than 1/13 wave figure error when measured at 633 nanometers. The aerial density of these films is 0.037 kilograms per square meter. Several 0.5-meter spherical mirrors were also manufactured. These mirrors had excellent surface finish (1.5 nanometers rms) and figure error on the order of tens of microns. This places their figure error within the demonstrated correctability of advanced wavefront correction technologies such as real time holography.

  5. Prompt and Precise Prototyping

    NASA Technical Reports Server (NTRS)

    2003-01-01

    For Sanders Design International, Inc., of Wilton, New Hampshire, every passing second between the concept and realization of a product is essential to succeed in the rapid prototyping industry where amongst heavy competition, faster time-to-market means more business. To separate itself from its rivals, Sanders Design aligned with NASA's Marshall Space Flight Center to develop what it considers to be the most accurate rapid prototyping machine for fabrication of extremely precise tooling prototypes. The company's Rapid ToolMaker System has revolutionized production of high quality, small-to-medium sized prototype patterns and tooling molds with an exactness that surpasses that of computer numerically-controlled (CNC) machining devices. Created with funding and support from Marshall under a Small Business Innovation Research (SBIR) contract, the Rapid ToolMaker is a dual-use technology with applications in both commercial and military aerospace fields. The advanced technology provides cost savings in the design and manufacturing of automotive, electronic, and medical parts, as well as in other areas of consumer interest, such as jewelry and toys. For aerospace applications, the Rapid ToolMaker enables fabrication of high-quality turbine and compressor blades for jet engines on unmanned air vehicles, aircraft, and missiles.

  6. Arrival Metering Precision Study

    NASA Technical Reports Server (NTRS)

    Prevot, Thomas; Mercer, Joey; Homola, Jeffrey; Hunt, Sarah; Gomez, Ashley; Bienert, Nancy; Omar, Faisal; Kraut, Joshua; Brasil, Connie; Wu, Minghong, G.

    2015-01-01

    This paper describes the background, method and results of the Arrival Metering Precision Study (AMPS) conducted in the Airspace Operations Laboratory at NASA Ames Research Center in May 2014. The simulation study measured delivery accuracy, flight efficiency, controller workload, and acceptability of time-based metering operations to a meter fix at the terminal area boundary for different resolution levels of metering delay times displayed to the air traffic controllers and different levels of airspeed information made available to the Time-Based Flow Management (TBFM) system computing the delay. The results show that the resolution of the delay countdown timer (DCT) on the controllers display has a significant impact on the delivery accuracy at the meter fix. Using the 10 seconds rounded and 1 minute rounded DCT resolutions resulted in more accurate delivery than 1 minute truncated and were preferred by the controllers. Using the speeds the controllers entered into the fourth line of the data tag to update the delay computation in TBFM in high and low altitude sectors increased air traffic control efficiency and reduced fuel burn for arriving aircraft during time based metering.

  7. High precision radial velocities with GIANO spectra

    NASA Astrophysics Data System (ADS)

    Carleo, I.; Sanna, N.; Gratton, R.; Benatti, S.; Bonavita, M.; Oliva, E.; Origlia, L.; Desidera, S.; Claudi, R.; Sissa, E.

    2016-06-01

    Radial velocities (RV) measured from near-infrared (NIR) spectra are a potentially excellent tool to search for extrasolar planets around cool or active stars. High resolution infrared (IR) spectrographs now available are reaching the high precision of visible instruments, with a constant improvement over time. GIANO is an infrared echelle spectrograph at the Telescopio Nazionale Galileo (TNG) and it is a powerful tool to provide high resolution spectra for accurate RV measurements of exoplanets and for chemical and dynamical studies of stellar or extragalactic objects. No other high spectral resolution IR instrument has GIANO's capability to cover the entire NIR wavelength range (0.95-2.45 μm) in a single exposure. In this paper we describe the ensemble of procedures that we have developed to measure high precision RVs on GIANO spectra acquired during the Science Verification (SV) run, using the telluric lines as wavelength reference. We used the Cross Correlation Function (CCF) method to determine the velocity for both the star and the telluric lines. For this purpose, we constructed two suitable digital masks that include about 2000 stellar lines, and a similar number of telluric lines. The method is applied to various targets with different spectral type, from K2V to M8 stars. We reached different precisions mainly depending on the H-magnitudes: for H ˜ 5 we obtain an rms scatter of ˜ 10 m s-1, while for H ˜ 9 the standard deviation increases to ˜ 50 ÷ 80 m s-1. The corresponding theoretical error expectations are ˜ 4 m s-1 and 30 m s-1, respectively. Finally we provide the RVs measured with our procedure for the targets observed during GIANO Science Verification.

  8. Ensemble MD simulations restrained via crystallographic data: Accurate structure leads to accurate dynamics

    PubMed Central

    Xue, Yi; Skrynnikov, Nikolai R

    2014-01-01

    Currently, the best existing molecular dynamics (MD) force fields cannot accurately reproduce the global free-energy minimum which realizes the experimental protein structure. As a result, long MD trajectories tend to drift away from the starting coordinates (e.g., crystallographic structures). To address this problem, we have devised a new simulation strategy aimed at protein crystals. An MD simulation of protein crystal is essentially an ensemble simulation involving multiple protein molecules in a crystal unit cell (or a block of unit cells). To ensure that average protein coordinates remain correct during the simulation, we introduced crystallography-based restraints into the MD protocol. Because these restraints are aimed at the ensemble-average structure, they have only minimal impact on conformational dynamics of the individual protein molecules. So long as the average structure remains reasonable, the proteins move in a native-like fashion as dictated by the original force field. To validate this approach, we have used the data from solid-state NMR spectroscopy, which is the orthogonal experimental technique uniquely sensitive to protein local dynamics. The new method has been tested on the well-established model protein, ubiquitin. The ensemble-restrained MD simulations produced lower crystallographic R factors than conventional simulations; they also led to more accurate predictions for crystallographic temperature factors, solid-state chemical shifts, and backbone order parameters. The predictions for 15N R1 relaxation rates are at least as accurate as those obtained from conventional simulations. Taken together, these results suggest that the presented trajectories may be among the most realistic protein MD simulations ever reported. In this context, the ensemble restraints based on high-resolution crystallographic data can be viewed as protein-specific empirical corrections to the standard force fields. PMID:24452989

  9. High precision innovative micropump for artificial pancreas

    NASA Astrophysics Data System (ADS)

    Chappel, E.; Mefti, S.; Lettieri, G.-L.; Proennecke, S.; Conan, C.

    2014-03-01

    The concept of artificial pancreas, which comprises an insulin pump, a continuous glucose meter and a control algorithm, is a major step forward in managing patient with type 1 diabetes mellitus. The stability of the control algorithm is based on short-term precision micropump to deliver rapid-acting insulin and to specific integrated sensors able to monitor any failure leading to a loss of accuracy. Debiotech's MEMS micropump, based on the membrane pump principle, is made of a stack of 3 silicon wafers. The pumping chamber comprises a pillar check-valve at the inlet, a pumping membrane which is actuated against stop limiters by a piezo cantilever, an anti-free-flow outlet valve and a pressure sensor. The micropump inlet is tightly connected to the insulin reservoir while the outlet is in direct communication with the patient skin via a cannula. To meet the requirement of a pump dedicated to closed-loop application for diabetes care, in addition to the well-controlled displacement of the pumping membrane, the high precision of the micropump is based on specific actuation profiles that balance effect of pump elasticity in low-consumption push-pull mode.

  10. Precise positioning method for multi-process connecting based on binocular vision

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Ding, Lichao; Zhao, Kai; Li, Xiao; Wang, Ling; Jia, Zhenyuan

    2016-01-01

    With the rapid development of aviation and aerospace, the demand for metal coating parts such as antenna reflector, eddy-current sensor and signal transmitter, etc. is more and more urgent. Such parts with varied feature dimensions, complex three-dimensional structures, and high geometric accuracy are generally fabricated by the combination of different manufacturing technology. However, it is difficult to ensure the machining precision because of the connection error between different processing methods. Therefore, a precise positioning method is proposed based on binocular micro stereo vision in this paper. Firstly, a novel and efficient camera calibration method for stereoscopic microscope is presented to solve the problems of narrow view field, small depth of focus and too many nonlinear distortions. Secondly, the extraction algorithms for law curve and free curve are given, and the spatial position relationship between the micro vision system and the machining system is determined accurately. Thirdly, a precise positioning system based on micro stereovision is set up and then embedded in a CNC machining experiment platform. Finally, the verification experiment of the positioning accuracy is conducted and the experimental results indicated that the average errors of the proposed method in the X and Y directions are 2.250 μm and 1.777 μm, respectively.

  11. High Frequency QRS ECG Accurately Detects Cardiomyopathy

    NASA Technical Reports Server (NTRS)

    Schlegel, Todd T.; Arenare, Brian; Poulin, Gregory; Moser, Daniel R.; Delgado, Reynolds

    2005-01-01

    High frequency (HF, 150-250 Hz) analysis over the entire QRS interval of the ECG is more sensitive than conventional ECG for detecting myocardial ischemia. However, the accuracy of HF QRS ECG for detecting cardiomyopathy is unknown. We obtained simultaneous resting conventional and HF QRS 12-lead ECGs in 66 patients with cardiomyopathy (EF = 23.2 plus or minus 6.l%, mean plus or minus SD) and in 66 age- and gender-matched healthy controls using PC-based ECG software recently developed at NASA. The single most accurate ECG parameter for detecting cardiomyopathy was an HF QRS morphological score that takes into consideration the total number and severity of reduced amplitude zones (RAZs) present plus the clustering of RAZs together in contiguous leads. This RAZ score had an area under the receiver operator curve (ROC) of 0.91, and was 88% sensitive, 82% specific and 85% accurate for identifying cardiomyopathy at optimum score cut-off of 140 points. Although conventional ECG parameters such as the QRS and QTc intervals were also significantly longer in patients than controls (P less than 0.001, BBBs excluded), these conventional parameters were less accurate (area under the ROC = 0.77 and 0.77, respectively) than HF QRS morphological parameters for identifying underlying cardiomyopathy. The total amplitude of the HF QRS complexes, as measured by summed root mean square voltages (RMSVs), also differed between patients and controls (33.8 plus or minus 11.5 vs. 41.5 plus or minus 13.6 mV, respectively, P less than 0.003), but this parameter was even less accurate in distinguishing the two groups (area under ROC = 0.67) than the HF QRS morphologic and conventional ECG parameters. Diagnostic accuracy was optimal (86%) when the RAZ score from the HF QRS ECG and the QTc interval from the conventional ECG were used simultaneously with cut-offs of greater than or equal to 40 points and greater than or equal to 445 ms, respectively. In conclusion 12-lead HF QRS ECG employing

  12. High precision during food recruitment of experienced (reactivated) foragers in the stingless bee Scaptotrigona mexicana (Apidae, Meliponini)

    NASA Astrophysics Data System (ADS)

    Sánchez, Daniel; Nieh, James C.; Hénaut, Yann; Cruz, Leopoldo; Vandame, Rémy

    Several studies have examined the existence of recruitment communication mechanisms in stingless bees. However, the spatial accuracy of location-specific recruitment has not been examined. Moreover, the location-specific recruitment of reactivated foragers, i.e., foragers that have previously experienced the same food source at a different location and time, has not been explicitly examined. However, such foragers may also play a significant role in colony foraging, particularly in small colonies. Here we report that reactivated Scaptotrigona mexicana foragers can recruit with high precision to a specific food location. The recruitment precision of reactivated foragers was evaluated by placing control feeders to the left and the right of the training feeder (direction-precision tests) and between the nest and the training feeder and beyond it (distance-precision tests). Reactivated foragers arrived at the correct location with high precision: 98.44% arrived at the training feeder in the direction trials (five-feeder fan-shaped array, accuracy of at least +/-6° of azimuth at 50 m from the nest), and 88.62% arrived at the training feeder in the distance trials (five-feeder linear array, accuracy of at least +/-5 m or +/-10% at 50 m from the nest). Thus, S. mexicana reactivated foragers can find the indicated food source at a specific distance and direction with high precision, higher than that shown by honeybees, Apis mellifera, which do not communicate food location at such close distances to the nest.

  13. Separation of Platinum from Palladium and Iridium in Iron Meteorites and Accurate High-Precision Determination of Platinum Isotopes by Multi-Collector ICP-MS.

    PubMed

    Hunt, Alison C; Ek, Mattias; Schönbächler, Maria

    2017-12-01

    This study presents a new measurement procedure for the isolation of Pt from iron meteorite samples. The method also allows for the separation of Pd from the same sample aliquot. The separation entails a two-stage anion-exchange procedure. In the first stage, Pt and Pd are separated from each other and from major matrix constituents including Fe and Ni. In the second stage, Ir is reduced with ascorbic acid and eluted from the column before Pt collection. Platinum yields for the total procedure were typically 50-70%. After purification, high-precision Pt isotope determinations were performed by multi-collector ICP-MS. The precision of the new method was assessed using the IIAB iron meteorite North Chile. Replicate analyses of multiple digestions of this material yielded an intermediate precision for the measurement results of 0.73 for ε 192 Pt, 0.15 for ε 194 Pt and 0.09 for ε 196 Pt (2 standard deviations). The NIST SRM 3140 Pt solution reference material was passed through the measurement procedure and yielded an isotopic composition that is identical to the unprocessed Pt reference material. This indicates that the new technique is unbiased within the limit of the estimated uncertainties. Data for three iron meteorites support that Pt isotope variations in these samples are due to exposure to galactic cosmic rays in space.

  14. Ion traps for precision experiments at rare-isotope-beam facilities

    NASA Astrophysics Data System (ADS)

    Kwiatkowski, Anna

    2016-09-01

    Ion traps first entered experimental nuclear physics when the ISOLTRAP team demonstrated Penning trap mass spectrometry of radionuclides. From then on, the demand for ion traps has grown at radioactive-ion-beam (RIB) facilities since beams can be tailored for the desired experiment. Ion traps have been deployed for beam preparation, from bunching (thereby allowing time coincidences) to beam purification. Isomerically pure beams needed for nuclear-structure investigations can be prepared for trap-assisted or in-trap decay spectroscopy. The latter permits studies of highly charged ions for stellar evolution, which would be impossible with traditional experimental nuclear-physics methods. Moreover, the textbook-like conditions and advanced ion manipulation - even of a single ion - permit high-precision experiments. Consequently, the most accurate and precise mass measurements are now performed in Penning traps. After a brief introduction to ion trapping, I will focus on examples which showcase the versatility and utility of the technique at RIB facilities. I will demonstrate how this atomic-physics technique has been integrated into nuclear science, accelerator physics, and chemistry. DOE.

  15. Precisely Tracking Childhood Death

    PubMed Central

    Farag, Tamer H.; Koplan, Jeffrey P.; Breiman, Robert F.; Madhi, Shabir A.; Heaton, Penny M.; Mundel, Trevor; Ordi, Jaume; Bassat, Quique; Menendez, Clara; Dowell, Scott F.

    2017-01-01

    Abstract. Little is known about the specific causes of neonatal and under-five childhood death in high-mortality geographic regions due to a lack of primary data and dependence on inaccurate tools, such as verbal autopsy. To meet the ambitious new Sustainable Development Goal 3.2 to eliminate preventable child mortality in every country, better approaches are needed to precisely determine specific causes of death so that prevention and treatment interventions can be strengthened and focused. Minimally invasive tissue sampling (MITS) is a technique that uses needle-based postmortem sampling, followed by advanced histopathology and microbiology to definitely determine cause of death. The Bill & Melinda Gates Foundation is supporting a new surveillance system called the Child Health and Mortality Prevention Surveillance network, which will determine cause of death using MITS in combination with other information, and yield cause-specific population-based mortality rates, eventually in up to 12–15 sites in sub-Saharan Africa and south Asia. However, the Gates Foundation funding alone is not enough. We call on governments, other funders, and international stakeholders to expand the use of pathology-based cause of death determination to provide the information needed to end preventable childhood mortality. PMID:28719334

  16. Precisely Tracking Childhood Death.

    PubMed

    Farag, Tamer H; Koplan, Jeffrey P; Breiman, Robert F; Madhi, Shabir A; Heaton, Penny M; Mundel, Trevor; Ordi, Jaume; Bassat, Quique; Menendez, Clara; Dowell, Scott F

    2017-07-01

    Little is known about the specific causes of neonatal and under-five childhood death in high-mortality geographic regions due to a lack of primary data and dependence on inaccurate tools, such as verbal autopsy. To meet the ambitious new Sustainable Development Goal 3.2 to eliminate preventable child mortality in every country, better approaches are needed to precisely determine specific causes of death so that prevention and treatment interventions can be strengthened and focused. Minimally invasive tissue sampling (MITS) is a technique that uses needle-based postmortem sampling, followed by advanced histopathology and microbiology to definitely determine cause of death. The Bill & Melinda Gates Foundation is supporting a new surveillance system called the Child Health and Mortality Prevention Surveillance network, which will determine cause of death using MITS in combination with other information, and yield cause-specific population-based mortality rates, eventually in up to 12-15 sites in sub-Saharan Africa and south Asia. However, the Gates Foundation funding alone is not enough. We call on governments, other funders, and international stakeholders to expand the use of pathology-based cause of death determination to provide the information needed to end preventable childhood mortality.

  17. Precise positioning with sparse radio tracking: How LRO-LOLA and GRAIL enable future lunar exploration

    NASA Astrophysics Data System (ADS)

    Mazarico, E.; Goossens, S. J.; Barker, M. K.; Neumann, G. A.; Zuber, M. T.; Smith, D. E.

    2017-12-01

    Two recent NASA missions to the Moon, the Lunar Reconnaissance Orbiter (LRO) and the Gravity Recovery and Interior Laboratory (GRAIL), have obtained highly accurate information about the lunar shape and gravity field. These global geodetic datasets resolve long-standing issues with mission planning; the tidal lock of the Moon long prevented collection of accurate gravity measurements over the farside, and deteriorated precise positioning of topographic data. We describe key datasets and results from the LRO and GRAIL mission that are directly relevant to future lunar missions. SmallSat and CubeSat missions especially would benefit from these recent improvements, as they are typically more resource-constrained. Even with limited radio tracking data, accurate knowledge of topography and gravity enables precise orbit determination (OD) (e.g., limiting the scope of geolocation and co-registration tasks) and long-term predictions of altitude (e.g., dramatically reducing uncertainties in impact time). With one S-band tracking pass per day, LRO OD now routinely achieves total position knowledge better than 10 meters and radial position knowledge around 0.5 meter. Other tracking data, such as Laser Ranging from Earth-based SLR stations, can further support OD. We also show how altimetry can be used to substantially improve orbit reconstruction with the accurate topographic maps now available from Lunar Orbiter Laser Altimeter (LOLA) data. We present new results with SELENE extended mission and LRO orbits processed with direct altimetry measurements. With even a simple laser altimeter onboard, high-quality OD can be achieved for future missions because of the datasets acquired by LRO and GRAIL, without the need for regular radio contact. Onboard processing of altimetric ranges would bring high-quality real-time position knowledge to support autonomous operation. We also describe why optical ranging transponders are ideal payloads for future lunar missions, as they can

  18. High-precision measurement of phenylalanine δ15N values for environmental samples: a new approach coupling high-pressure liquid chromatography purification and elemental analyzer isotope ratio mass spectrometry.

    PubMed

    Broek, Taylor A B; Walker, Brett D; Andreasen, Dyke H; McCarthy, Matthew D

    2013-11-15

    Compound-specific isotope analysis of individual amino acids (CSI-AA) is a powerful new tool for tracing nitrogen (N) source and transformation in biogeochemical cycles. Specifically, the δ(15)N value of phenylalanine (δ(15)N(Phe)) represents an increasingly used proxy for source δ(15)N signatures, with particular promise for paleoceanographic applications. However, current derivatization/gas chromatography methods require expensive and relatively uncommon instrumentation, and have relatively low precision, making many potential applications impractical. A new offline approach has been developed for high-precision δ(15)N measurements of amino acids (δ(15)N(AA)), optimized for δ(15)N(Phe) values. Amino acids (AAs) are first purified via high-pressure liquid chromatography (HPLC), using a mixed-phase column and automated fraction collection. The δ(15)N values are determined via offline elemental analyzer-isotope ratio mass spectrometry (EA-IRMS). The combined HPLC/EA-IRMS method separated most protein AAs with sufficient resolution to obtain accurate δ(15)N values, despite significant intra-peak isotopic fractionation. For δ(15)N(Phe) values, the precision was ±0.16‰ for standards, 4× better than gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS; ±0.64‰). We also compared a δ(15)N(Phe) paleo-record from a deep-sea bamboo coral from Monterey Bay, CA, USA, using our method versus GC/C/IRMS. The two methods produced equivalent δ(15)N(Phe) values within error; however, the δ(15)N(Phe) values from HPLC/EA-IRMS had approximately twice the precision of GC/C/IRMS (average stdev of 0.27‰ ± 0.14‰ vs 0.60‰ ± 0.20‰, respectively). These results demonstrate that offline HPLC represents a viable alternative to traditional GC/C/IMRS for δ(15)N(AA) measurement. HPLC/EA-IRMS is more precise and widely available, and therefore useful in applications requiring increased precision for data interpretation (e.g. δ(15)N paleoproxies

  19. Precise attitude determination of defunct satellite laser ranging tragets

    NASA Astrophysics Data System (ADS)

    Pittet, Jean-Noel; Schildknecht, Thomas; Silha, Jiri

    2016-07-01

    The Satellite Laser Ranging (SLR) technology is used to determine the dynamics of objects equipped with so-called retro-reflectors or retro-reflector arrays (RRA). This type of measurement allows to range to the spacecraft with very high precision, which leads to determination of very accurate orbits. Non-active spacecraft, which are not any more attitude controlled, tend to start to spin or tumble under influence of the external and internal torques. Such a spinning can be around one constant axis of rotation or it can be more complex, when also precession and nutation motions are present. The rotation of the RRA around the spacecraft's centre of mass can create both a oscillation pattern of laser range signal and a periodic signal interruption when the RRA is hidden behind the satellite. In our work we will demonstrate how the SLR ranging technique to cooperative targets can be used to determine precisely their attitude state. The processing of the obtained data will be discussed, as well as the attitude determination based on parameters estimation. Continuous SLR measurements to one target can allow to accurately monitor attitude change over time which can be further used for the future attitude modelling. We will show our solutions of the attitude states determined for the non-active ESA satellite ENVISAT based on measurements acquired during year 2013-2015 by Zimmerwald SLR station, Switzerland. The angular momentum shows a stable behaviour with respect to the orbital plane but is not aligned with orbital momentum. The determination of the inertial rotation over time, shows it evolving between 130 to 190 seconds within two year. Parameter estimation also bring a strong indication of a retrograde rotation. Results on other former satellites in low and medium Earth orbit such as TOPEX/Poseidon or GLONASS type will be also presented.

  20. No galaxy left behind: accurate measurements with the faintest objects in the Dark Energy Survey

    NASA Astrophysics Data System (ADS)

    Suchyta, E.; Huff, E. M.; Aleksić, J.; Melchior, P.; Jouvel, S.; MacCrann, N.; Ross, A. J.; Crocce, M.; Gaztanaga, E.; Honscheid, K.; Leistedt, B.; Peiris, H. V.; Rykoff, E. S.; Sheldon, E.; Abbott, T.; Abdalla, F. B.; Allam, S.; Banerji, M.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Burke, D. L.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Estrada, J.; Evrard, A. E.; Flaugher, B.; Fosalba, P.; Frieman, J.; Gerdes, D. W.; Gruen, D.; Gruendl, R. A.; James, D. J.; Jarvis, M.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Lima, M.; Maia, M. A. G.; March, M.; Marshall, J. L.; Miller, C. J.; Miquel, R.; Neilsen, E.; Nichol, R. C.; Nord, B.; Ogando, R.; Percival, W. J.; Reil, K.; Roodman, A.; Sako, M.; Sanchez, E.; Scarpine, V.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Vikram, V.; Walker, A. R.; Wechsler, R. H.; Zhang, Y.; DES Collaboration

    2016-03-01

    Accurate statistical measurement with large imaging surveys has traditionally required throwing away a sizable fraction of the data. This is because most measurements have relied on selecting nearly complete samples, where variations in the composition of the galaxy population with seeing, depth, or other survey characteristics are small. We introduce a new measurement method that aims to minimize this wastage, allowing precision measurement for any class of detectable stars or galaxies. We have implemented our proposal in BALROG, software which embeds fake objects in real imaging to accurately characterize measurement biases. We demonstrate this technique with an angular clustering measurement using Dark Energy Survey (DES) data. We first show that recovery of our injected galaxies depends on a variety of survey characteristics in the same way as the real data. We then construct a flux-limited sample of the faintest galaxies in DES, chosen specifically for their sensitivity to depth and seeing variations. Using the synthetic galaxies as randoms in the Landy-Szalay estimator suppresses the effects of variable survey selection by at least two orders of magnitude. With this correction, our measured angular clustering is found to be in excellent agreement with that of a matched sample from much deeper, higher resolution space-based Cosmological Evolution Survey (COSMOS) imaging; over angular scales of 0.004° < θ < 0.2°, we find a best-fitting scaling amplitude between the DES and COSMOS measurements of 1.00 ± 0.09. We expect this methodology to be broadly useful for extending measurements' statistical reach in a variety of upcoming imaging surveys.

  1. Precise predictions for V+jets dark matter backgrounds

    NASA Astrophysics Data System (ADS)

    Lindert, J. M.; Pozzorini, S.; Boughezal, R.; Campbell, J. M.; Denner, A.; Dittmaier, S.; Gehrmann-De Ridder, A.; Gehrmann, T.; Glover, N.; Huss, A.; Kallweit, S.; Maierhöfer, P.; Mangano, M. L.; Morgan, T. A.; Mück, A.; Petriello, F.; Salam, G. P.; Schönherr, M.; Williams, C.

    2017-12-01

    High-energy jets recoiling against missing transverse energy (MET) are powerful probes of dark matter at the LHC. Searches based on large MET signatures require a precise control of the Z(ν {\\bar{ν }})+ jet background in the signal region. This can be achieved by taking accurate data in control regions dominated by Z(ℓ ^+ℓ ^-)+ jet, W(ℓ ν )+ jet and γ + jet production, and extrapolating to the Z(ν {\\bar{ν }})+ jet background by means of precise theoretical predictions. In this context, recent advances in perturbative calculations open the door to significant sensitivity improvements in dark matter searches. In this spirit, we present a combination of state-of-the-art calculations for all relevant V+ jets processes, including throughout NNLO QCD corrections and NLO electroweak corrections supplemented by Sudakov logarithms at two loops. Predictions at parton level are provided together with detailed recommendations for their usage in experimental analyses based on the reweighting of Monte Carlo samples. Particular attention is devoted to the estimate of theoretical uncertainties in the framework of dark matter searches, where subtle aspects such as correlations across different V+ jet processes play a key role. The anticipated theoretical uncertainty in the Z(ν {\\bar{ν }})+ jet background is at the few percent level up to the TeV range.

  2. Accurate mass and velocity functions of dark matter haloes

    NASA Astrophysics Data System (ADS)

    Comparat, Johan; Prada, Francisco; Yepes, Gustavo; Klypin, Anatoly

    2017-08-01

    N-body cosmological simulations are an essential tool to understand the observed distribution of galaxies. We use the MultiDark simulation suite, run with the Planck cosmological parameters, to revisit the mass and velocity functions. At redshift z = 0, the simulations cover four orders of magnitude in halo mass from ˜1011M⊙ with 8783 874 distinct haloes and 532 533 subhaloes. The total volume used is ˜515 Gpc3, more than eight times larger than in previous studies. We measure and model the halo mass function, its covariance matrix w.r.t halo mass and the large-scale halo bias. With the formalism of the excursion-set mass function, we explicit the tight interconnection between the covariance matrix, bias and halo mass function. We obtain a very accurate (<2 per cent level) model of the distinct halo mass function. We also model the subhalo mass function and its relation to the distinct halo mass function. The set of models obtained provides a complete and precise framework for the description of haloes in the concordance Planck cosmology. Finally, we provide precise analytical fits of the Vmax maximum velocity function up to redshift z < 2.3 to push for the development of halo occupation distribution using Vmax. The data and the analysis code are made publicly available in the Skies and Universes data base.

  3. Specific material recognition by small peptides mediated by the interfacial solvent structure.

    PubMed

    Schneider, Julian; Ciacchi, Lucio Colombi

    2012-02-01

    We present evidence that specific material recognition by small peptides is governed by local solvent density variations at solid/liquid interfaces, sensed by the side-chain residues with atomic-scale precision. In particular, we unveil the origin of the selectivity of the binding motif RKLPDA for Ti over Si using a combination of metadynamics and steered molecular dynamics simulations, obtaining adsorption free energies and adhesion forces in quantitative agreement with corresponding experiments. For an accurate description, we employ realistic models of the natively oxidized surfaces which go beyond the commonly used perfect crystal surfaces. These results have profound implications for nanotechnology and materials science applications, offering a previously missing structure-function relationship for the rational design of materials-selective peptide sequences. © 2011 American Chemical Society

  4. Precise Documentation: The Key to Better Software

    NASA Astrophysics Data System (ADS)

    Parnas, David Lorge

    The prime cause of the sorry “state of the art” in software development is our failure to produce good design documentation. Poor documentation is the cause of many errors and reduces efficiency in every phase of a software product's development and use. Most software developers believe that “documentation” refers to a collection of wordy, unstructured, introductory descriptions, thousands of pages that nobody wanted to write and nobody trusts. In contrast, Engineers in more traditional disciplines think of precise blueprints, circuit diagrams, and mathematical specifications of component properties. Software developers do not know how to produce precise documents for software. Software developments also think that documentation is something written after the software has been developed. In other fields of Engineering much of the documentation is written before and during the development. It represents forethought not afterthought. Among the benefits of better documentation would be: easier reuse of old designs, better communication about requirements, more useful design reviews, easier integration of separately written modules, more effective code inspection, more effective testing, and more efficient corrections and improvements. This paper explains how to produce and use precise software documentation and illustrate the methods with several examples.

  5. Configuration and Specifications of AN Unmanned Aerial Vehicle for Precision Agriculture

    NASA Astrophysics Data System (ADS)

    Erena, M.; Montesinos, S.; Portillo, D.; Alvarez, J.; Marin, C.; Fernandez, L.; Henarejos, J. M.; Ruiz, L. A.

    2016-06-01

    Unmanned Aerial Vehicles (UAVs) with multispectral sensors are increasingly attractive in geosciences for data capture and map updating at high spatial and temporal resolutions. These autonomously-flying systems can be equipped with different sensors, such as a six-band multispectral camera (Tetracam mini-MCA-6), GPS Ublox M8N, and MEMS gyroscopes, and miniaturized sensor systems for navigation, positioning, and mapping purposes. These systems can be used for data collection in precision viticulture. In this study, the efficiency of a light UAV system for data collection, processing, and map updating in small areas is evaluated, generating correlations between classification maps derived from remote sensing and production maps. Based on the comparison of the indices derived from UAVs incorporating infrared sensors with those obtained by satellites (Sentinel 2A and Landsat 8), UAVs show promise for the characterization of vineyard plots with high spatial variability, despite the low vegetative coverage of these crops. Consequently, a procedure for zoning map production based on UAV/UV images could provide important information for farmers.

  6. Selective Influences of Precision and Power Grips on Speech Categorization.

    PubMed

    Tiainen, Mikko; Tiippana, Kaisa; Vainio, Martti; Peromaa, Tarja; Komeilipoor, Naeem; Vainio, Lari

    2016-01-01

    Recent studies have shown that articulatory gestures are systematically associated with specific manual grip actions. Here we show that executing such actions can influence performance on a speech-categorization task. Participants watched and/or listened to speech stimuli while executing either a power or a precision grip. Grip performance influenced the syllable categorization by increasing the proportion of responses of the syllable congruent with the executed grip (power grip-[ke] and precision grip-[te]). Two follow-up experiments indicated that the effect was based on action-induced bias in selecting the syllable.

  7. Molecular profiling of sarcomas: new vistas for precision medicine.

    PubMed

    Al-Zaid, Tariq; Wang, Wei-Lien; Somaiah, Neeta; Lazar, Alexander J

    2017-08-01

    Sarcoma is a large and heterogeneous group of malignant mesenchymal neoplasms with significant histological overlap. Accurate diagnosis can be challenging yet important for selecting the appropriate treatment approach and prognosis. The currently torrid pace of new genomic discoveries aids our classification and diagnosis of sarcomas, understanding of pathogenesis, development of new medications, and identification of alterations that predict prognosis and response to therapy. Unfortunately, demonstrating effective targets for precision oncology has been elusive in most sarcoma types. The list of potential targets greatly outnumbers the list of available inhibitors at the present time. This review will discuss the role of molecular profiling in sarcomas in general with emphasis on selected entities with particular clinical relevance.

  8. Morphologies of precise polyethylene-based acid copolymers and ionomers

    NASA Astrophysics Data System (ADS)

    Buitrago, C. Francisco

    Acid copolymers and ionomers are polymers that contain a small fraction of covalently bound acidic or ionic groups, respectively. For the specific case of polyethylene (PE), acid and ionic pendants enhance many of the physical properties such as toughness, adhesion and rheological properties. These improved properties result from microphase separated aggregates of the polar pendants in the non-polar PE matrix. Despite the widespread industrial use of these materials, rigorous chemical structure---morphology---property relationships remain elusive due to the inevitable structural heterogeneities in the historically-available acid copolymers and ionomers. Recently, precise acid copolymers and ionomers were successfully synthesized by acyclic diene metathesis (ADMET) polymerization. These precise materials are linear, high molecular weight PEs with pendant acid or ionic functional groups separated by a precisely controlled number of carbon atoms. The morphologies of nine precise acid copolymers and eleven precise ionomers were investigated by X-ray scattering, solid-state 13C nuclear magnetic resonance (NMR) and differential scanning calorimetry (DSC). For comparison, the morphologies of linear PEs with pseudo-random placement of the pendant groups were also studied. Previous studies of precise copolymers with acrylic acid (AA) found that the microstructural precision produces a new morphology in which PE crystals drive the acid aggregates into layers perpendicular to the chain axes and presumably at the interface between crystalline and amorphous phases. In this dissertation, a second new morphology for acid copolymers is identified in which the aggregates arrange on cubic lattices. The fist report of a cubic morphology was observed at room and elevated temperatures for a copolymer functionalized with two phosphonic acid (PA) groups on every 21st carbon atom. The cubic lattice has been identified as face-centered cubic (FCC). Overall, three morphology types have been

  9. A novel design of the high-precision magnetic locator with three-dimension measurement capability applying dynamically sensing mechanism

    NASA Astrophysics Data System (ADS)

    Huang, Wen-Nan; Chen, Po-Shen; Chen, Mu-Ping; Teng, Ching-Cheng

    2006-09-01

    A novel design of the magnetic locator, for obtaining the high-precision measurement information of variety of the buried metal pipes, is presented in this paper. The concept of dynamically sensing mechanism, including the vibrating and moving devices, proposed herein is a simple and effective way to improve the precision of three-dimension location sensing for the underground utilities. Based on the primary magnetism of Lenz's law and Faraday's law, the functions of the amplifying effect for the sensing magnetic signals, as well as the distinguishing effect by the simple filtering algorithms embedded in processing programs, are achieved while the relatively strong noise exists. The verification results of these integration designs demonstrate the effectiveness both by precise locating for the buried utility, and accurate measurement for the depth.

  10. The emerging potential for network analysis to inform precision cancer medicine.

    PubMed

    Ozturk, Kivilcim; Dow, Michelle; Carlin, Daniel E; Bejar, Rafael; Carter, Hannah

    2018-06-14

    Precision cancer medicine promises to tailor clinical decisions to patients using genomic information. Indeed, successes of drugs targeting genetic alterations in tumors, such as imatinib that targets BCR-ABL in chronic myelogenous leukemia, have demonstrated the power of this approach. However biological systems are complex, and patients may differ not only by the specific genetic alterations in their tumor, but by more subtle interactions among such alterations. Systems biology and more specifically, network analysis, provides a framework for advancing precision medicine beyond clinical actionability of individual mutations. Here we discuss applications of network analysis to study tumor biology, early methods for N-of-1 tumor genome analysis and the path for such tools to the clinic. Copyright © 2018. Published by Elsevier Ltd.

  11. Specification Reformulation During Specification Validation

    NASA Technical Reports Server (NTRS)

    Benner, Kevin M.

    1992-01-01

    The goal of the ARIES Simulation Component (ASC) is to uncover behavioral errors by 'running' a specification at the earliest possible points during the specification development process. The problems to be overcome are the obvious ones the specification may be large, incomplete, underconstrained, and/or uncompilable. This paper describes how specification reformulation is used to mitigate these problems. ASC begins by decomposing validation into specific validation questions. Next, the specification is reformulated to abstract out all those features unrelated to the identified validation question thus creating a new specialized specification. ASC relies on a precise statement of the validation question and a careful application of transformations so as to preserve the essential specification semantics in the resulting specialized specification. This technique is a win if the resulting specialized specification is small enough so the user my easily handle any remaining obstacles to execution. This paper will: (1) describe what a validation question is; (2) outline analysis techniques for identifying what concepts are and are not relevant to a validation question; and (3) identify and apply transformations which remove these less relevant concepts while preserving those which are relevant.

  12. The 230Th correction is the 1st priority for accurate dates of young zircons: U/Th partitioning experiments and measurements

    NASA Astrophysics Data System (ADS)

    Krawczynski, M.; McLean, N.

    2017-12-01

    One of the most accurate and useful ways of determining the age of rocks that formed more than about 500,000 years ago is uranium-lead (U-Pb) geochronology. Earth scientists use U-Pb geochronology to put together the geologic history of entire regions and of specific events, like the mass extinction of all non-avian dinosaurs about 66 million years ago or the catastrophic eruptions of supervolcanoes like the one currently centered at Yellowstone. The mineral zircon is often utilized because it is abundant, durable, and readily incorporates uranium into its crystal structure. But it excludes thorium, whose isotope 230Th is part of the naturally occurring isotopic decay chain from 238U to 206Pb. Calculating a date from the relative abundances of 206Pb and 238U therefore requires a correction for the missing 230Th. Existing experimental and observational constraints on the way U and Th behave when zircon crystallizes from a melt are not known precisely enough, and thus currently the uncertainty in dates introduced by they `Th correction' is one of the largest sources of systematic error in determining dates. Here we present preliminary results on our study of actinide partitioning between zircon and melt. Experiments have been conducted to grow zircon from melts doped with U and Th that mimic natural magmas at a range of temperatures, and compositions. Synthetic zircons are separated from their coexisting glass and using high precision and high-spatial-resolution techniques, the abundance and distribution of U and Th in each phase is determined. These preliminary experiments are the beginning of a study that will result in precise determination of the zircon/melt uranium and thorium partition coefficients under a wide variety of naturally occurring conditions. This data will be fit to a multidimensional surface using maximum likelihood regression techniques, so that the ratio of partition coefficients can be calculated for any set of known parameters. The results of

  13. Application of Multimodality Imaging Fusion Technology in Diagnosis and Treatment of Malignant Tumors under the Precision Medicine Plan.

    PubMed

    Wang, Shun-Yi; Chen, Xian-Xia; Li, Yi; Zhang, Yu-Ying

    2016-12-20

    The arrival of precision medicine plan brings new opportunities and challenges for patients undergoing precision diagnosis and treatment of malignant tumors. With the development of medical imaging, information on different modality imaging can be integrated and comprehensively analyzed by imaging fusion system. This review aimed to update the application of multimodality imaging fusion technology in the precise diagnosis and treatment of malignant tumors under the precision medicine plan. We introduced several multimodality imaging fusion technologies and their application to the diagnosis and treatment of malignant tumors in clinical practice. The data cited in this review were obtained mainly from the PubMed database from 1996 to 2016, using the keywords of "precision medicine", "fusion imaging", "multimodality", and "tumor diagnosis and treatment". Original articles, clinical practice, reviews, and other relevant literatures published in English were reviewed. Papers focusing on precision medicine, fusion imaging, multimodality, and tumor diagnosis and treatment were selected. Duplicated papers were excluded. Multimodality imaging fusion technology plays an important role in tumor diagnosis and treatment under the precision medicine plan, such as accurate location, qualitative diagnosis, tumor staging, treatment plan design, and real-time intraoperative monitoring. Multimodality imaging fusion systems could provide more imaging information of tumors from different dimensions and angles, thereby offing strong technical support for the implementation of precision oncology. Under the precision medicine plan, personalized treatment of tumors is a distinct possibility. We believe that multimodality imaging fusion technology will find an increasingly wide application in clinical practice.

  14. Research on the Rapid and Accurate Positioning and Orientation Approach for Land Missile-Launching Vehicle

    PubMed Central

    Li, Kui; Wang, Lei; Lv, Yanhong; Gao, Pengyu; Song, Tianxiao

    2015-01-01

    Getting a land vehicle’s accurate position, azimuth and attitude rapidly is significant for vehicle based weapons’ combat effectiveness. In this paper, a new approach to acquire vehicle’s accurate position and orientation is proposed. It uses biaxial optical detection platform (BODP) to aim at and lock in no less than three pre-set cooperative targets, whose accurate positions are measured beforehand. Then, it calculates the vehicle’s accurate position, azimuth and attitudes by the rough position and orientation provided by vehicle based navigation systems and no less than three couples of azimuth and pitch angles measured by BODP. The proposed approach does not depend on Global Navigation Satellite System (GNSS), thus it is autonomous and difficult to interfere. Meanwhile, it only needs a rough position and orientation as algorithm’s iterative initial value, consequently, it does not have high performance requirement for Inertial Navigation System (INS), odometer and other vehicle based navigation systems, even in high precise applications. This paper described the system’s working procedure, presented theoretical deviation of the algorithm, and then verified its effectiveness through simulation and vehicle experiments. The simulation and experimental results indicate that the proposed approach can achieve positioning and orientation accuracy of 0.2 m and 20″ respectively in less than 3 min. PMID:26492249

  15. Research on the rapid and accurate positioning and orientation approach for land missile-launching vehicle.

    PubMed

    Li, Kui; Wang, Lei; Lv, Yanhong; Gao, Pengyu; Song, Tianxiao

    2015-10-20

    Getting a land vehicle's accurate position, azimuth and attitude rapidly is significant for vehicle based weapons' combat effectiveness. In this paper, a new approach to acquire vehicle's accurate position and orientation is proposed. It uses biaxial optical detection platform (BODP) to aim at and lock in no less than three pre-set cooperative targets, whose accurate positions are measured beforehand. Then, it calculates the vehicle's accurate position, azimuth and attitudes by the rough position and orientation provided by vehicle based navigation systems and no less than three couples of azimuth and pitch angles measured by BODP. The proposed approach does not depend on Global Navigation Satellite System (GNSS), thus it is autonomous and difficult to interfere. Meanwhile, it only needs a rough position and orientation as algorithm's iterative initial value, consequently, it does not have high performance requirement for Inertial Navigation System (INS), odometer and other vehicle based navigation systems, even in high precise applications. This paper described the system's working procedure, presented theoretical deviation of the algorithm, and then verified its effectiveness through simulation and vehicle experiments. The simulation and experimental results indicate that the proposed approach can achieve positioning and orientation accuracy of 0.2 m and 20″ respectively in less than 3 min.

  16. Accurate and Simple Screw Insertion Procedure With Patient-Specific Screw Guide Templates for Posterior C1-C2 Fixation.

    PubMed

    Sugawara, Taku; Higashiyama, Naoki; Kaneyama, Shuichi; Sumi, Masatoshi

    2017-03-15

    Prospective clinical trial of the screw insertion method for posterior C1-C2 fixation utilizing the patient-specific screw guide template technique. To evaluate the efficacy of this method for insertion of C1 lateral mass screws (LMS), C2 pedicle screws (PS), and C2 laminar screws (LS). Posterior C1LMS and C2PS fixation, also known as the Goel-Harms method, can achieve immediate rigid fixation and high fusion rate, but the screw insertion carries the risk of injury to neuronal and vascular structures. Dissection of venous plexus and C2 nerve root to confirm the insertion point of the C1LMS may also cause problems. We have developed an intraoperative screw guiding method using patient-specific laminar templates. Preoperative bone images of computed tomography (CT) were analyzed using three-dimensional (3D)/multiplanar imaging software to plan the trajectories of the screws. Plastic templates with screw guiding structures were created for each lamina using 3D design and printing technology. Three types of templates were made for precise multistep guidance, and all templates were specially designed to fit and lock on the lamina during the procedure. Surgery was performed using this patient-specific screw guide template system, and placement of the screws was postoperatively evaluated using CT. Twelve patients with C1-C2 instability were treated with a total of 48 screws (24 C1LMS, 20 C2PS, 4 C2LS). Intraoperatively, each template was found to exactly fit and lock on the lamina and screw insertion was completed successfully without dissection of the venous plexus and C2 nerve root. Postoperative CT showed no cortical violation by the screws, and mean deviation of the screws from the planned trajectories was 0.70 ± 0.42 mm. The multistep, patient-specific screw guide template system is useful for intraoperative screw navigation in posterior C1-C2 fixation. This simple and economical method can improve the accuracy of screw insertion, and reduce operation time and

  17. Pico-coulomb charge measured at BELLA to percent-level precision using a Turbo-ICT

    NASA Astrophysics Data System (ADS)

    Nakamura, K.; Mittelberger, D. E.; Gonsalves, A. J.; Daniels, J.; Mao, H.-S.; Stulle, F.; Bergoz, J.; Leemans, W. P.

    2016-03-01

    Precise diagnostics of picocoulomb level particle bunches produced by laser plasma accelerators (LPAs) can be a significant challenge. Without proper care, the small signals associated with such bunches can be dominated by a background generated by laser, target, laser-plasma interaction and particle induced radiation. In this paper, we report on first charge measurements using the newly developed Turbo-ICT for LPAs. We outline the Turbo-ICT working principle, which allows precise sub-picocoulomb measurements even in the presence of significant background signals. A comparison of the Turbo-ICT, a conventional integrating current transformer (ICT) and a scintillating screen (Lanex) was carried out at the Berkeley Lab Laser Accelerator. Results show that the Turbo-ICT can measure sub-picocoulomb charge accurately and has significantly improved noise immunity compared to the ICT.

  18. Repression by PRDM13 is critical for generating precision in neuronal identity

    PubMed Central

    Kollipara, Rahul K; Ma, Zhenzhong; Borromeo, Mark D; Chang, Joshua C

    2017-01-01

    The mechanisms that activate some genes while silencing others are critical to ensure precision in lineage specification as multipotent progenitors become restricted in cell fate. During neurodevelopment, these mechanisms are required to generate the diversity of neuronal subtypes found in the nervous system. Here we report interactions between basic helix-loop-helix (bHLH) transcriptional activators and the transcriptional repressor PRDM13 that are critical for specifying dorsal spinal cord neurons. PRDM13 inhibits gene expression programs for excitatory neuronal lineages in the dorsal neural tube. Strikingly, PRDM13 also ensures a battery of ventral neural tube specification genes such as Olig1, Olig2 and Prdm12 are excluded dorsally. PRDM13 does this via recruitment to chromatin by multiple neural bHLH factors to restrict gene expression in specific neuronal lineages. Together these findings highlight the function of PRDM13 in repressing the activity of bHLH transcriptional activators that together are required to achieve precise neuronal specification during mouse development. PMID:28850031

  19. Revisit to three-dimensional percolation theory: Accurate analysis for highly stretchable conductive composite materials

    PubMed Central

    Kim, Sangwoo; Choi, Seongdae; Oh, Eunho; Byun, Junghwan; Kim, Hyunjong; Lee, Byeongmoon; Lee, Seunghwan; Hong, Yongtaek

    2016-01-01

    A percolation theory based on variation of conductive filler fraction has been widely used to explain the behavior of conductive composite materials under both small and large deformation conditions. However, it typically fails in properly analyzing the materials under the large deformation since the assumption may not be valid in such a case. Therefore, we proposed a new three-dimensional percolation theory by considering three key factors: nonlinear elasticity, precisely measured strain-dependent Poisson’s ratio, and strain-dependent percolation threshold. Digital image correlation (DIC) method was used to determine actual Poisson’s ratios at various strain levels, which were used to accurately estimate variation of conductive filler volume fraction under deformation. We also adopted strain-dependent percolation threshold caused by the filler re-location with deformation. When three key factors were considered, electrical performance change was accurately analyzed for composite materials with both isotropic and anisotropic mechanical properties. PMID:27694856

  20. An efficient and accurate 3D displacements tracking strategy for digital volume correlation

    NASA Astrophysics Data System (ADS)

    Pan, Bing; Wang, Bo; Wu, Dafang; Lubineau, Gilles

    2014-07-01

    Owing to its inherent computational complexity, practical implementation of digital volume correlation (DVC) for internal displacement and strain mapping faces important challenges in improving its computational efficiency. In this work, an efficient and accurate 3D displacement tracking strategy is proposed for fast DVC calculation. The efficiency advantage is achieved by using three improvements. First, to eliminate the need of updating Hessian matrix in each iteration, an efficient 3D inverse compositional Gauss-Newton (3D IC-GN) algorithm is introduced to replace existing forward additive algorithms for accurate sub-voxel displacement registration. Second, to ensure the 3D IC-GN algorithm that converges accurately and rapidly and avoid time-consuming integer-voxel displacement searching, a generalized reliability-guided displacement tracking strategy is designed to transfer accurate and complete initial guess of deformation for each calculation point from its computed neighbors. Third, to avoid the repeated computation of sub-voxel intensity interpolation coefficients, an interpolation coefficient lookup table is established for tricubic interpolation. The computational complexity of the proposed fast DVC and the existing typical DVC algorithms are first analyzed quantitatively according to necessary arithmetic operations. Then, numerical tests are performed to verify the performance of the fast DVC algorithm in terms of measurement accuracy and computational efficiency. The experimental results indicate that, compared with the existing DVC algorithm, the presented fast DVC algorithm produces similar precision and slightly higher accuracy at a substantially reduced computational cost.

  1. Clinical evaluation of the FreeStyle Precision Pro system.

    PubMed

    Brazg, Ronald; Hughes, Kristen; Martin, Pamela; Coard, Julie; Toffaletti, John; McDonnell, Elizabeth; Taylor, Elizabeth; Farrell, Lausanne; Patel, Mona; Ward, Jeanne; Chen, Ting; Alva, Shridhara; Ng, Ronald

    2013-06-05

    A new version of international standard (ISO 15197) and CLSI Guideline (POCT12) with more stringent accuracy criteria are near publication. We evaluated the glucose test performance of the FreeStyle Precision Pro system, a new blood glucose monitoring system (BGMS) designed to enhance accuracy for point-of-care testing (POCT). Precision, interference and system accuracy with 503 blood samples from capillary, venous and arterial sources were evaluated in a multicenter study. Study results were analyzed and presented in accordance with the specifications and recommendations of the final draft ISO 15197 and the new POCT12. The FreeStyle Precision Pro system demonstrated acceptable precision (CV <5%), no interference across a hematocrit range of 15-65%, and, except for xylose, no interference from 24 of 25 potentially interfering substances. It also met all accuracy criteria specified in the final draft ISO 15197 and POCT12, with 97.3-98.9% of the individual results of various blood sample types agreeing within ±12 mg/dl of the laboratory analyzer values at glucose concentrations <100mg/dl and within ±12.5% of the laboratory analyzer values at glucose concentrations ≥100 mg/dl. The FreeStyle Precision Pro system met the tighter accuracy requirements, providing a means for enhancing accuracy for point-of-care blood glucose monitoring. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Comparison of Vehicle-Broadcasted Fuel Consumption Rates against Precise Fuel Measurements for Medium- and Heavy-Duty Vehicles and Engines

    DOE PAGES

    Pink, Alex; Ragatz, Adam; Wang, Lijuan; ...

    2017-03-28

    Vehicles continuously report real-time fuel consumption estimates over their data bus, known as the controller area network (CAN). However, the accuracy of these fueling estimates is uncertain to researchers who collect these data from any given vehicle. To assess the accuracy of these estimates, CAN-reported fuel consumption data are compared against fuel measurements from precise instrumentation. The data analyzed consisted of eight medium/heavy-duty vehicles and two medium-duty engines. Varying discrepancies between CAN fueling rates and the more accurate measurements emerged but without a vehicular trend-for some vehicles the CAN under-reported fuel consumption and for others the CAN over-reported fuel consumption.more » Furthermore, a qualitative real-time analysis revealed that the operating conditions under which these fueling discrepancies arose varied among vehicles. A drive cycle analysis revealed that while CAN fueling estimate accuracy differs for individual vehicles, that CAN estimates capture the relative fuel consumption differences between drive cycles within 4% for all vehicles and even more accurately for some vehicles. Furthermore, in situations where only CAN-reported data are available, CAN fueling estimates can provide relative fuel consumption trends but not accurate or precise fuel consumption rates.« less

  3. Comparison of Vehicle-Broadcasted Fuel Consumption Rates against Precise Fuel Measurements for Medium- and Heavy-Duty Vehicles and Engines

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

    Pink, Alex; Ragatz, Adam; Wang, Lijuan

    Vehicles continuously report real-time fuel consumption estimates over their data bus, known as the controller area network (CAN). However, the accuracy of these fueling estimates is uncertain to researchers who collect these data from any given vehicle. To assess the accuracy of these estimates, CAN-reported fuel consumption data are compared against fuel measurements from precise instrumentation. The data analyzed consisted of eight medium/heavy-duty vehicles and two medium-duty engines. Varying discrepancies between CAN fueling rates and the more accurate measurements emerged but without a vehicular trend-for some vehicles the CAN under-reported fuel consumption and for others the CAN over-reported fuel consumption.more » Furthermore, a qualitative real-time analysis revealed that the operating conditions under which these fueling discrepancies arose varied among vehicles. A drive cycle analysis revealed that while CAN fueling estimate accuracy differs for individual vehicles, that CAN estimates capture the relative fuel consumption differences between drive cycles within 4% for all vehicles and even more accurately for some vehicles. Furthermore, in situations where only CAN-reported data are available, CAN fueling estimates can provide relative fuel consumption trends but not accurate or precise fuel consumption rates.« less

  4. Accurate PSF-matched photometry for the J-PAS survey

    NASA Astrophysics Data System (ADS)

    Jimenez-Teja, Yolanda; Benitez, Txitxo; Dupke, Renato a.

    2015-08-01

    The Javalambre-PAU Astrophysical Survey (J-PAS) is expected to map 8,600 squared-degrees of the sky using 54 narrow and 5 broad band filters. Carried out by a Spanish-Brazilian consortium, the main goal of this survey is to measure Baryon Acoustic Oscillations (BAOs) with photometric redshifts. The expectation is measuring these photometric redshifts with a precision of dz/(1 + z) ~ 0.003 for 100 million galaxies and a few millions of quasars, and reaching an accuracy of dz/(1 + z) ~ 0.01 for other 300 million galaxies. With these numbers, it will be possible to determine w in the Dark Energy (DE) equation of state with an accuracy of < 4%. To achieve such precision and measure the radial BAOs, not only an advanced technical setup but also special data processing tools are required. These tools must be accurate as well as suitable to be implemented in fully automated and computationally efficient algorithms.The factor that most influences the photometric redshift precision is the quality of the photometry. For that reason we have developed a new technique based on the Chebyshev-Fourier bases (CHEFs, Jiménez-Teja & Benítez 2012, ApJ, 745, 150) to obtain a highly precise multicolor photometry without PSF consideration, thus saving a considerable amount of time and circumventing severe problems such as the PSF variability across the images. The CHEFs are a set of mathematical orthonormal bases with different scale and resolution levels, originally designed to fit the surface light distribution of galaxies. They have proved to be able to model any kind of morphology, including spirals, highly elliptical, or irregular galaxies, including isophotal twists and fine substructure. They also fit high signal-to-noise images, lensing arcs and stars with great accuracy. We can calculate optimal, unbiased, total magnitudes directly through these CHEFs models and, thus, colors without needing the PSF.We compare our photometry with widely-used codes such as SExtractor (Bertin

  5. Accurate Determination of the Values of Fundamental Physical Constants: The Basis of the New "Quantum" SI Units

    NASA Astrophysics Data System (ADS)

    Karshenboim, S. G.

    2018-03-01

    The metric system appeared as the system of units designed for macroscopic (laboratory scale) measurements. The progress in accurate determination of the values of quantum constants (such as the Planck constant) in SI units shows that the capabilities in high-precision measurement of microscopic and macroscopic quantities in terms of the same units have increased substantially recently. At the same time, relative microscopic measurements (for example, the comparison of atomic transition frequencies or atomic masses) are often much more accurate than relative measurements of macroscopic quantities. This is the basis for the strategy to define units in microscopic phenomena and then use them on the laboratory scale, which plays a crucial role in practical methodological applications determined by everyday life and technologies. The international CODATA task group on fundamental constants regularly performs an overall analysis of the precision world data (the so-called Adjustment of the Fundamental Constants) and publishes their recommended values. The most recent evaluation was based on the data published by the end of 2014; here, we review the corresponding data and results. The accuracy in determination of the Boltzmann constant has increased, the consistency of the data on determination of the Planck constant has improved; it is these two dimensional constants that will be used in near future as the basis for the new definition of the kelvin and kilogram, respectively. The contradictions in determination of the Rydberg constant and the proton charge radius remain. The accuracy of determination of the fine structure constant and relative atomic weight of the electron has improved. Overall, we give a detailed review of the state of the art in precision determination of the values of fundamental constants. The mathematical procedure of the Adjustment, the new data and results are considered in detail. The limitations due to macroscopic properties of material

  6. Variational calculation of second-order reduced density matrices by strong N-representability conditions and an accurate semidefinite programming solver.

    PubMed

    Nakata, Maho; Braams, Bastiaan J; Fujisawa, Katsuki; Fukuda, Mituhiro; Percus, Jerome K; Yamashita, Makoto; Zhao, Zhengji

    2008-04-28

    The reduced density matrix (RDM) method, which is a variational calculation based on the second-order reduced density matrix, is applied to the ground state energies and the dipole moments for 57 different states of atoms, molecules, and to the ground state energies and the elements of 2-RDM for the Hubbard model. We explore the well-known N-representability conditions (P, Q, and G) together with the more recent and much stronger T1 and T2(') conditions. T2(') condition was recently rederived and it implies T2 condition. Using these N-representability conditions, we can usually calculate correlation energies in percentage ranging from 100% to 101%, whose accuracy is similar to CCSD(T) and even better for high spin states or anion systems where CCSD(T) fails. Highly accurate calculations are carried out by handling equality constraints and/or developing multiple precision arithmetic in the semidefinite programming (SDP) solver. Results show that handling equality constraints correctly improves the accuracy from 0.1 to 0.6 mhartree. Additionally, improvements by replacing T2 condition with T2(') condition are typically of 0.1-0.5 mhartree. The newly developed multiple precision arithmetic version of SDP solver calculates extraordinary accurate energies for the one dimensional Hubbard model and Be atom. It gives at least 16 significant digits for energies, where double precision calculations gives only two to eight digits. It also provides physically meaningful results for the Hubbard model in the high correlation limit.

  7. Metabolomics enables precision medicine: "A White Paper, Community Perspective".

    PubMed

    Beger, Richard D; Dunn, Warwick; Schmidt, Michael A; Gross, Steven S; Kirwan, Jennifer A; Cascante, Marta; Brennan, Lorraine; Wishart, David S; Oresic, Matej; Hankemeier, Thomas; Broadhurst, David I; Lane, Andrew N; Suhre, Karsten; Kastenmüller, Gabi; Sumner, Susan J; Thiele, Ines; Fiehn, Oliver; Kaddurah-Daouk, Rima

    Metabolomics is the comprehensive study of the metabolome, the repertoire of biochemicals (or small molecules) present in cells, tissues, and body fluids. The study of metabolism at the global or "-omics" level is a rapidly growing field that has the potential to have a profound impact upon medical practice. At the center of metabolomics, is the concept that a person's metabolic state provides a close representation of that individual's overall health status. This metabolic state reflects what has been encoded by the genome, and modified by diet, environmental factors, and the gut microbiome. The metabolic profile provides a quantifiable readout of biochemical state from normal physiology to diverse pathophysiologies in a manner that is often not obvious from gene expression analyses. Today, clinicians capture only a very small part of the information contained in the metabolome, as they routinely measure only a narrow set of blood chemistry analytes to assess health and disease states. Examples include measuring glucose to monitor diabetes, measuring cholesterol and high density lipoprotein/low density lipoprotein ratio to assess cardiovascular health, BUN and creatinine for renal disorders, and measuring a panel of metabolites to diagnose potential inborn errors of metabolism in neonates. We anticipate that the narrow range of chemical analyses in current use by the medical community today will be replaced in the future by analyses that reveal a far more comprehensive metabolic signature. This signature is expected to describe global biochemical aberrations that reflect patterns of variance in states of wellness, more accurately describe specific diseases and their progression, and greatly aid in differential diagnosis. Such future metabolic signatures will: (1) provide predictive, prognostic, diagnostic, and surrogate markers of diverse disease states; (2) inform on underlying molecular mechanisms of diseases; (3) allow for sub-classification of diseases, and

  8. Design of a soil cutting resistance sensor for application in site-specific tillage.

    PubMed

    Agüera, Juan; Carballido, Jacob; Gil, Jesús; Gliever, Chris J; Perez-Ruiz, Manuel

    2013-05-10

    One objective of precision agriculture is to provide accurate information about soil and crop properties to optimize the management of agricultural inputs to meet site-specific needs. This paper describes the development of a sensor equipped with RTK-GPS technology that continuously and efficiently measures soil cutting resistance at various depths while traversing the field. Laboratory and preliminary field tests verified the accuracy of this prototype soil strength sensor. The data obtained using a hand-operated soil cone penetrometer was used to evaluate this field soil compaction depth profile sensor. To date, this sensor has only been tested in one field under one gravimetric water content condition. This field test revealed that the relationships between the soil strength profile sensor (SSPS) cutting force and soil cone index values are assumed to be quadratic for the various depths considered: 0-10, 10-20 and 20-30 cm (r2 = 0.58, 0.45 and 0.54, respectively). Soil resistance contour maps illustrated its practical value. The developed sensor provides accurate, timely and affordable information on soil properties to optimize resources and improve agricultural economy.

  9. Accurate van der Waals force field for gas adsorption in porous materials.

    PubMed

    Sun, Lei; Yang, Li; Zhang, Ya-Dong; Shi, Qi; Lu, Rui-Feng; Deng, Wei-Qiao

    2017-09-05

    An accurate van der Waals force field (VDW FF) was derived from highly precise quantum mechanical (QM) calculations. Small molecular clusters were used to explore van der Waals interactions between gas molecules and porous materials. The parameters of the accurate van der Waals force field were determined by QM calculations. To validate the force field, the prediction results from the VDW FF were compared with standard FFs, such as UFF, Dreiding, Pcff, and Compass. The results from the VDW FF were in excellent agreement with the experimental measurements. This force field can be applied to the prediction of the gas density (H 2 , CO 2 , C 2 H 4 , CH 4 , N 2 , O 2 ) and adsorption performance inside porous materials, such as covalent organic frameworks (COFs), zeolites and metal organic frameworks (MOFs), consisting of H, B, N, C, O, S, Si, Al, Zn, Mg, Ni, and Co. This work provides a solid basis for studying gas adsorption in porous materials. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  10. PROMISE of Coronary CT Angiography: Precise and Accurate Diagnosis and Prognosis in Coronary Artery Disease.

    PubMed

    Thomas, Dustin M; Branch, Kelley R; Cury, Ricardo C

    2016-04-01

    Coronary computed tomography angiography (CCTA) is a rapidly growing and powerful diagnostic test that offers a great deal of precision with respect to diagnosing coronary artery disease (CAD). Guideline statements for patients with stable ischemic heart disease have recommended CCTA for only a limited portion of intermediate-risk patients who have relative or absolute contraindications for exercise or vasodilator stress testing. The publication of two large, prospective randomized clinical trials, the Prospective Multicenter Imaging Study for Evaluation of Chest Pain and the Scottish Computed Tomography of the Heart Trial are likely to expand these indications. These new data from large trials, in addition to other studies, show that CCTA is highly sensitive for the detection of CAD, identifies high-risk patients for cardiac events based on extent or plaque morphology of CAD that would not be identified by other noninvasive means, and provides significantly greater diagnostic certainty for proper treatment, including referral for invasive coronary angiography with revascularization more appropriately. Superior diagnostic accuracy and prognostic data with CCTA, when compared with other functional stress tests, may result in a reduction in unnecessary downstream testing and cost savings. In addition, newer CCTA applications hold the promise of providing a complete evaluation of a patient's coronary anatomy as well as a per-vessel ischemic evaluation. This review focuses on the interval knowledge obtained from newer data on CCTA in patients with stable ischemic heart disease, primarily focusing on the contributions of the Prospective Multicenter Imaging Study for Evaluation of Chest Pain and the Scottish Computed Tomography of the Heart Trial.

  11. Accurate de novo design of hyperstable constrained peptides

    PubMed Central

    Bhardwaj, Gaurav; Mulligan, Vikram Khipple; Bahl, Christopher D.; Gilmore, Jason M.; Harvey, Peta J.; Cheneval, Olivier; Buchko, Garry W.; Pulavarti, Surya V.S.R.K.; Kaas, Quentin; Eletsky, Alexander; Huang, Po-Ssu; Johnsen, William A.; Greisen, Per; Rocklin, Gabriel J.; Song, Yifan; Linsky, Thomas W.; Watkins, Andrew; Rettie, Stephen A.; Xu, Xianzhong; Carter, Lauren P.; Bonneau, Richard; Olson, James M.; Coutsias, Evangelos; Correnti, Colin E.; Szyperski, Thomas; Craik, David J.; Baker, David

    2016-01-01

    Summary Naturally occurring, pharmacologically active peptides constrained with covalent crosslinks generally have shapes evolved to fit precisely into binding pockets on their targets. Such peptides can have excellent pharmaceutical properties, combining the stability and tissue penetration of small molecule drugs with the specificity of much larger protein therapeutics. The ability to design constrained peptides with precisely specified tertiary structures would enable the design of shape-complementary inhibitors of arbitrary targets. Here we describe the development of computational methods for de novo design of conformationally-restricted peptides, and the use of these methods to design 15–50 residue disulfide-crosslinked and heterochiral N-C backbone-cyclized peptides. These peptides are exceptionally stable to thermal and chemical denaturation, and twelve experimentally-determined X-ray and NMR structures are nearly identical to the computational models. The computational design methods and stable scaffolds presented here provide the basis for development of a new generation of peptide-based drugs. PMID:27626386

  12. Field variability and vulnerability index to identify precision agriculture opportunity

    USDA-ARS?s Scientific Manuscript database

    Innovations in precision agriculture (PA) have created opportunities to achieve a greater understanding of within-field variability. However, PA adoption has been hindered due to uncertainty about field-specific performance and return on investment. Uncertainty could be better addressed by analyzing...

  13. High-precision timeline for Earth's most severe extinction.

    PubMed

    Burgess, Seth D; Bowring, Samuel; Shen, Shu-zhong

    2014-03-04

    The end-Permian mass extinction was the most severe loss of marine and terrestrial biota in the last 542 My. Understanding its cause and the controls on extinction/recovery dynamics depends on an accurate and precise age model. U-Pb zircon dates for five volcanic ash beds from the Global Stratotype Section and Point for the Permian-Triassic boundary at Meishan, China, define an age model for the extinction and allow exploration of the links between global environmental perturbation, carbon cycle disruption, mass extinction, and recovery at millennial timescales. The extinction occurred between 251.941 ± 0.037 and 251.880 ± 0.031 Mya, an interval of 60 ± 48 ka. Onset of a major reorganization of the carbon cycle immediately precedes the initiation of extinction and is punctuated by a sharp (3‰), short-lived negative spike in the isotopic composition of carbonate carbon. Carbon cycle volatility persists for ∼500 ka before a return to near preextinction values. Decamillenial to millennial level resolution of the mass extinction and its aftermath will permit a refined evaluation of the relative roles of rate-dependent processes contributing to the extinction, allowing insight into postextinction ecosystem expansion, and establish an accurate time point for evaluating the plausibility of trigger and kill mechanisms.

  14. An ultra-precision tool nanoindentation instrument for replication of single point diamond tool cutting edges

    NASA Astrophysics Data System (ADS)

    Cai, Yindi; Chen, Yuan-Liu; Xu, Malu; Shimizu, Yuki; Ito, So; Matsukuma, Hiraku; Gao, Wei

    2018-05-01

    Precision replication of the diamond tool cutting edge is required for non-destructive tool metrology. This paper presents an ultra-precision tool nanoindentation instrument designed and constructed for replication of the cutting edge of a single point diamond tool onto a selected soft metal workpiece by precisely indenting the tool cutting edge into the workpiece surface. The instrument has the ability to control the indentation depth with a nanometric resolution, enabling the replication of tool cutting edges with high precision. The motion of the diamond tool along the indentation direction is controlled by the piezoelectric actuator of a fast tool servo (FTS). An integrated capacitive sensor of the FTS is employed to detect the displacement of the diamond tool. The soft metal workpiece is attached to an aluminum cantilever whose deflection is monitored by another capacitive sensor, referred to as an outside capacitive sensor. The indentation force and depth can be accurately evaluated from the diamond tool displacement, the cantilever deflection and the cantilever spring constant. Experiments were carried out by replicating the cutting edge of a single point diamond tool with a nose radius of 2.0 mm on a copper workpiece surface. The profile of the replicated tool cutting edge was measured using an atomic force microscope (AFM). The effectiveness of the instrument in precision replication of diamond tool cutting edges is well-verified by the experimental results.

  15. High-Precision U-Pb Geochronology of Ice River Perovskite: A Possible Interlaboratory and Intertechnique EARTHTIME Standard

    NASA Astrophysics Data System (ADS)

    Burgess, S. D.; Bowring, S. A.; Heaman, L. M.

    2012-12-01

    Accurate and precise U-Pb geochronology of accessory phases other than zircon are required for dating some LIP basalts or determining the temporal patterns of kimberlite pipes, for example. Advances in precision and accuracy lead directly to an increase in the complexity of questions that can be posed. U-Pb geochronology of perovskite (CaTiO3) has been applied to silica-undersaturated basalts, carbonatites, alkaline igneous rocks, and kimberlites. Most published IDTIMS perovskite dates have 2-sigma precisions at the ~0.2% level for weighted mean 206Pb/238U dates, much less than possible with IDTIMS analyses of zircons, which limits the applicability of perovskite in high-precision applications. Precision on perovskite dates is lower than zircon because of common Pb, which in some cases can be up to 50% of the total Pb and must be corrected for and accurately partitioned between blank and initial. Relatively small changes in the composition of common Pb can result in inaccurate but precise dates. In many cases minerals with significant common Pb are corrected using Stacey and Kramers (1975) two stage Pb evolution model. This can be done without serious consequence to the final date for minerals with high U/Pb ratios. In the more common case where U/Pb ratios are relatively low and the proportion of common Pb is large, applying a model-derived Pb isotopic composition rather than measuring it directly can introduce percent-level inaccuracy to dates calculated with precisely known U/Pb ratios. Direct measurement of the common Pb composition can be done on a U-poor mineral that co-crystallized with perovskite; feldspar and clinopyroxene are commonly used. Clinopyroxene can contain significant in-grown radiogenic Pb and our experiments indicate that it is not eliminated by aggressive step-wise leaching. The U/Pb ratio in clinopyroxene is generally low (20 < mu < 50) but significant. Other workers (e.g. Kamo et al., 2003; Corfu and Dahlgren, 2008), have used two methods

  16. Green Solvents for Precision Cleaning

    NASA Technical Reports Server (NTRS)

    Grandelli, Heather; Maloney, Phillip; DeVor, Robert; Surma, Jan; Hintze, Paul

    2013-01-01

    Aerospace machinery used in liquid oxygen (LOX) fuel systems must be precision cleaned to achieve a very low level of non-volatile residue (< 1 mg0.1 m2), especially flammable residue. Traditionally chlorofluorocarbons (CFCs) have been used in the precision cleaning of LOX systems, specifically CFC 113 (C2Cl3F3). CFCs have been known to cause the depletion of ozone and in 1987, were banned by the Montreal Protocol due to health, safety and environmental concerns. This has now led to the development of new processes in the precision cleaning of aerospace components. An ideal solvent-replacement is non-flammable, environmentally benign, non-corrosive, inexpensive, effective and evaporates completely, leaving no residue. Highlighted is a green precision cleaning process, which is contaminant removal using supercritical carbon dioxide as the environmentally benign solvent. In this process, the contaminant is dissolved in carbon dioxide, and the parts are recovered at the end of the cleaning process completely dry and ready for use. Typical contaminants of aerospace components include hydrocarbon greases, hydraulic fluids, silicone fluids and greases, fluorocarbon fluids and greases and fingerprint oil. Metallic aerospace components range from small nuts and bolts to much larger parts, such as butterfly valves 18 in diameter. A fluorinated grease, Krytox, is investigated as a model contaminant in these preliminary studies, and aluminum coupons are employed as a model aerospace component. Preliminary studies are presented in which the experimental parameters are optimized for removal of Krytox from aluminum coupons in a stirred-batch process. The experimental conditions investigated are temperature, pressure, exposure time and impeller speed. Temperatures of 308 - 423 K, pressures in the range of 8.3 - 41.4 MPa, exposure times between 5 - 60 min and impeller speeds of 0 - 1000 rpm were investigated. Preliminary results showed up to 86 cleaning efficiency with the

  17. Development of a precision reverse offset printing system

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

    Kim, Hyunchang; Lee, Eonseok; Choi, Young-Man

    2016-01-15

    In printed electronics technology, the overlay accuracy of printed patterns is a very important issue when applying printing technology to the production of electric devices. In order to achieve accurate positioning of the printed patterns, this study proposes a novel precision reverse offset printing system. Furthermore, the study evaluates the effects of synchronization and printing force on position errors of the printed patterns, and presents methods of controlling synchronization and printing force so as to eliminate positional errors caused by the above-mentioned reasons. Finally, the printing position repeatability of 0.40 μm and 0.32 μm (x and y direction, respectively) atmore » a sigma level is obtained over the dimension of 100 mm under repeated printing tests with identical printing conditions.« less

  18. Working memory recall precision is a more sensitive index than span.

    PubMed

    Zokaei, Nahid; Burnett Heyes, Stephanie; Gorgoraptis, Nikos; Budhdeo, Sanjay; Husain, Masud

    2015-09-01

    Delayed adjustment tasks have recently been developed to examine working memory (WM) precision, that is, the resolution with which items maintained in memory are recalled. However, despite their emerging use in experimental studies of healthy people, evaluation of patient populations is sparse. We first investigated the validity of adjustment tasks, comparing precision with classical span measures of memory across the lifespan in 114 people. Second, we asked whether precision measures can potentially provide a more sensitive measure of WM than traditional span measures. Specifically, we tested this hypothesis examining WM in a group with early, untreated Parkinson's disease (PD) and its modulation by subsequent treatment on dopaminergic medication. Span measures correlated with precision across the lifespan: in children, young, and elderly participants. However, they failed to detect changes in WM in PD patients, either pre- or post-treatment initiation. By contrast, recall precision was sensitive enough to pick up such changes. PD patients pre-medication were significantly impaired compared to controls, but improved significantly after 3 months of being established on dopaminergic medication. These findings suggest that precision methods might provide a sensitive means to investigate WM and its modulation by interventions in clinical populations. © 2014 The Authors Journal of Neuropsychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.

  19. Methods for the accurate estimation of confidence intervals on protein folding ϕ-values

    PubMed Central

    Ruczinski, Ingo; Sosnick, Tobin R.; Plaxco, Kevin W.

    2006-01-01

    ϕ-Values provide an important benchmark for the comparison of experimental protein folding studies to computer simulations and theories of the folding process. Despite the growing importance of ϕ measurements, however, formulas to quantify the precision with which ϕ is measured have seen little significant discussion. Moreover, a commonly employed method for the determination of standard errors on ϕ estimates assumes that estimates of the changes in free energy of the transition and folded states are independent. Here we demonstrate that this assumption is usually incorrect and that this typically leads to the underestimation of ϕ precision. We derive an analytical expression for the precision of ϕ estimates (assuming linear chevron behavior) that explicitly takes this dependence into account. We also describe an alternative method that implicitly corrects for the effect. By simulating experimental chevron data, we show that both methods accurately estimate ϕ confidence intervals. We also explore the effects of the commonly employed techniques of calculating ϕ from kinetics estimated at non-zero denaturant concentrations and via the assumption of parallel chevron arms. We find that these approaches can produce significantly different estimates for ϕ (again, even for truly linear chevron behavior), indicating that they are not equivalent, interchangeable measures of transition state structure. Lastly, we describe a Web-based implementation of the above algorithms for general use by the protein folding community. PMID:17008714

  20. Recommended volumetric capacity definitions and protocols for accurate, standardized and unambiguous metrics for hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Parilla, Philip A.; Gross, Karl; Hurst, Katherine; Gennett, Thomas

    2016-03-01

    The ultimate goal of the hydrogen economy is the development of hydrogen storage systems that meet or exceed the US DOE's goals for onboard storage in hydrogen-powered vehicles. In order to develop new materials to meet these goals, it is extremely critical to accurately, uniformly and precisely measure materials' properties relevant to the specific goals. Without this assurance, such measurements are not reliable and, therefore, do not provide a benefit toward the work at hand. In particular, capacity measurements for hydrogen storage materials must be based on valid and accurate results to ensure proper identification of promising materials for further development. Volumetric capacity determinations are becoming increasingly important for identifying promising materials, yet there exists controversy on how such determinations are made and whether such determinations are valid due to differing methodologies to count the hydrogen content. These issues are discussed herein, and we show mathematically that capacity determinations can be made rigorously and unambiguously if the constituent volumes are well defined and measurable in practice. It is widely accepted that this occurs for excess capacity determinations and we show here that this can happen for the total capacity determination. Because the adsorption volume is undefined, the absolute capacity determination remains imprecise. Furthermore, we show that there is a direct relationship between determining the respective capacities and the calibration constants used for the manometric and gravimetric techniques. Several suggested volumetric capacity figure-of-merits are defined, discussed and reporting requirements recommended. Finally, an example is provided to illustrate these protocols and concepts.

  1. [Precision and accuracy of "a pocket" pulse oximeter in Mexico City].

    PubMed

    Torre-Bouscoulet, Luis; Chávez-Plascencia, Elizabeth; Vázquez-García, Juan Carlos; Pérez-Padilla, Rogelio

    2006-01-01

    Pulse oximeters are frequently used in the clinical practice and we must known their precision and accuracy. The objective was to evaluate the precision and accuracy of a "pocket" pulse oximeter at an altitude of 2,240 m above sea level. We tested miniature pulse oximeters (Onyx 9,500, Nonin Finger Pulse Oximeter) in 96 patients sent to the pulmonary laboratory for an arterial blood sample. Patients were tested with 5 pulse oximeters placed in each of the fingers of the hand oposite to that used for the arterial puncture. The gold standard was the oxygen saturation of the arterial blood sample. Blood samples had SaO2 of 87.2 +/- 11.0 (between 42.2 and 97.9%). Pulse oximeters had a mean error of 0.28 +/- 3.1%. SaO2 = (1.204 x SpO2) - 17.45966 (r = 0.92, p < 0.0001). Intraclass correlation coefficient between each of five pulse oximeters against the arterial blood standard ranged between 0.87 and 0.99. HbCO (2.4 +/- 0.6) did not affect the accuracy. The miniature oximeter Nonin is precise and accurate at 2,240 m of altitude. The observed levels of HbCO did not affect the performance of the equipment. The oximeter good performance, small size and low cost enhances its clinical usefulness.

  2. Features of precision slot cutting with a large number of calibers using the radiation of a single-mode fiber laser

    NASA Astrophysics Data System (ADS)

    Vitshas, A. A.; Zelentsov, A. G.; Lopota, V. A.; Menakhin, V. P.; Panchenko, V. P.; Soroka, A. M.

    2014-02-01

    The results of the experimental and theoretical investigations aimed at determining the characteristics and features of precision slot cutting with a large number of calibers in sheets of low-carbon steel using the radiation of a single-mode fiber laser with pulse power up to 1 kW are presented. The description of the experimental installation, performance conditions of investigations, and variable parameters are described. Precision cutting of low-carbon steel up to 10 mm with the number of calibers ranging from 30 to 70 at a slot width of ≈60 μm is performed for the first time. Such cutting occurs only in the pulsed-periodic mode using single-mode radiation with a pulse duration of 2-3 ms, a pulse ratio of 2-4, and oxygen, whose influence differs in principle both in various cut regions over the sheet thickness and from cutting with a CO2 laser. The cutting velocity (100-50 mm/min) of sheet steel up to thicknesses of 10 mm with deep channeling, roughness parameters, hardness of the cut surface, which insignificantly (by ≈20%) exceeds the hardness of untreated steel, the phase structure of steel, and the scales of their varying inside metal are measured. The efficiency (≈3%) of precision cutting and the efficiency of transportation of radiation (25%) in large-caliber slot orifices in the "waveguide" mode are determined by the experimental data. The useful specific energy contribution of the laser radiation is w l = N l/( hbv) ≈ 2 × 1012 J/m2 for all studied thicknesses of sheet samples accurate to 20%. A qualitative model of the laser-oxygen precision cutting with deep channeling, which explains the cyclic and interrupting character of cutting and necessity of using oxygen as the cutting gas, is proposed.

  3. Number-Density Measurements of CO2 in Real Time with an Optical Frequency Comb for High Accuracy and Precision

    NASA Astrophysics Data System (ADS)

    Scholten, Sarah K.; Perrella, Christopher; Anstie, James D.; White, Richard T.; Al-Ashwal, Waddah; Hébert, Nicolas Bourbeau; Genest, Jérôme; Luiten, Andre N.

    2018-05-01

    Real-time and accurate measurements of gas properties are highly desirable for numerous real-world applications. Here, we use an optical-frequency comb to demonstrate absolute number-density and temperature measurements of a sample gas with state-of-the-art precision and accuracy. The technique is demonstrated by measuring the number density of 12C16O2 with an accuracy of better than 1% and a precision of 0.04% in a measurement and analysis cycle of less than 1 s. This technique is transferable to numerous molecular species, thus offering an avenue for near-universal gas concentration measurements.

  4. A Self Contained Method for Safe and Precise Lunar Landing

    NASA Technical Reports Server (NTRS)

    Paschall, Stephen C., II; Brady, Tye; Cohanim, Babak; Sostaric, Ronald

    2008-01-01

    The return of humans to the Moon will require increased capability beyond that of the previous Apollo missions. Longer stay times and a greater flexibility with regards to landing locations are among the many improvements planned. A descent and landing system that can land the vehicle more accurately than Apollo with a greater ability to detect and avoid hazards is essential to the development of a Lunar Outpost, and also for increasing the number of potentially reachable Lunar Sortie locations. This descent and landing system should allow landings in more challenging terrain and provide more flexibility with regards to mission timing and lighting considerations, while maintaining safety as the top priority. The lunar landing system under development by the ALHAT (Autonomous precision Landing and Hazard detection Avoidance Technology) project is addressing this by providing terrain-relative navigation measurements to enhance global-scale precision, an onboard hazard-detection system to select safe landing locations, and an Autonomous GNC (Guidance, Navigation, and Control) capability to process these measurements and safely direct the vehicle to this landing location. This ALHAT landing system will enable safe and precise lunar landings without requiring lunar infrastructure in the form of navigation aids or a priori identified hazard-free landing locations. The safe landing capability provided by ALHAT uses onboard active sensing to detect hazards that are large enough to be a danger to the vehicle but too small to be detected from orbit, given currently planned orbital terrain resolution limits. Algorithms to interpret raw active sensor terrain data and generate hazard maps as well as identify safe sites and recalculate new trajectories to those sites are included as part of the ALHAT System. These improvements to descent and landing will help contribute to repeated safe and precise landings for a wide variety of terrain on the Moon.

  5. [Precision and personalized medicine].

    PubMed

    Sipka, Sándor

    2016-10-01

    The author describes the concept of "personalized medicine" and the newly introduced "precision medicine". "Precision medicine" applies the terms of "phenotype", "endotype" and "biomarker" in order to characterize more precisely the various diseases. Using "biomarkers" the homogeneous type of a disease (a "phenotype") can be divided into subgroups called "endotypes" requiring different forms of treatment and financing. The good results of "precision medicine" have become especially apparent in relation with allergic and autoimmune diseases. The application of this new way of thinking is going to be necessary in Hungary, too, in the near future for participants, controllers and financing boards of healthcare. Orv. Hetil., 2016, 157(44), 1739-1741.

  6. Precision genome editing in the CRISPR era.

    PubMed

    Salsman, Jayme; Dellaire, Graham

    2017-04-01

    With the introduction of precision genome editing using CRISPR-Cas9 technology, we have entered a new era of genetic engineering and gene therapy. With RNA-guided endonucleases, such as Cas9, it is possible to engineer DNA double strand breaks (DSB) at specific genomic loci. DSB repair by the error-prone non-homologous end-joining (NHEJ) pathway can disrupt a target gene by generating insertions and deletions. Alternatively, Cas9-mediated DSBs can be repaired by homology-directed repair (HDR) using an homologous DNA repair template, thus allowing precise gene editing by incorporating genetic changes into the repair template. HDR can introduce gene sequences for protein epitope tags, delete genes, make point mutations, or alter enhancer and promoter activities. In anticipation of adapting this technology for gene therapy in human somatic cells, much focus has been placed on increasing the fidelity of CRISPR-Cas9 and increasing HDR efficiency to improve precision genome editing. In this review, we will discuss applications of CRISPR technology for gene inactivation and genome editing with a focus on approaches to enhancing CRISPR-Cas9-mediated HDR for the generation of cell and animal models, and conclude with a discussion of recent advances and challenges towards the application of this technology for gene therapy in humans.

  7. The Los Alamos National Laboratory precision double crystal spectrometer

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

    Morgan, D.V.; Stevens, C.J.; Liefield, R.J.

    1994-03-01

    This report discusses the following topics on the LANL precision double crystal X-ray spectrometer: Motivation for construction of the instrument; a brief history of the instrument; mechanical systems; motion control systems; computer control system; vacuum system; alignment program; scan programs; observations of the copper K{alpha} lines; and characteristics and specifications.

  8. Pragmatic precision oncology: the secondary uses of clinical tumor molecular profiling

    PubMed Central

    Thota, Ramya; Staggs, David B; Johnson, Douglas B; Warner, Jeremy L

    2016-01-01

    Background Precision oncology increasingly utilizes molecular profiling of tumors to determine treatment decisions with targeted therapeutics. The molecular profiling data is valuable in the treatment of individual patients as well as for multiple secondary uses. Objective To automatically parse, categorize, and aggregate clinical molecular profile data generated during cancer care as well as use this data to address multiple secondary use cases. Methods A system to parse, categorize and aggregate molecular profile data was created. A naÿve Bayesian classifier categorized results according to clinical groups. The accuracy of these systems were validated against a published expertly-curated subset of molecular profiling data. Results Following one year of operation, 819 samples have been accurately parsed and categorized to generate a data repository of 10,620 genetic variants. The database has been used for operational, clinical trial, and discovery science research. Conclusions A real-time database of molecular profiling data is a pragmatic solution to several knowledge management problems in the practice and science of precision oncology. PMID:27026612

  9. A novel method for accurate patterning and positioning of biological cells

    NASA Astrophysics Data System (ADS)

    Jing, Gaoshan; Labukas, Joseph P.; Iqbal, Aziz; Perry, Susan Fueshko; Ferguson, Gregory S.; Tatic-Lucic, Svetlana

    2007-05-01

    The ability to anchor cells in predefined patterns on a surface has become very important for the development of cell-based sensors, tissue-engineering applications, and the understanding of basic cell functions. Currently, the most widely used technique to generate micrometer or sub-micrometer-sized patterns for various biological applications is microcontact printing (μCP). However, the fidelity of the final pattern may be compromised by deformation of the PDMS stamps used during printing. A novel technique for accurately patterning and positioning biological cells is presented, which can overcome this obstacle. We have fabricated a chip on a silicon wafer using standard photolithographic and deposition processes consisting of gold patterns on top of PECVD silicon dioxide. A hydrophobic self-assembled monolayer (SAM) derived from 1-hexadecanethiol (HDT) was coated on the gold surface to prevent cell growth, and a hydrophilic SAM derived from (3-trimethoxysilyl propyl)-diethylenetriamine (DETA) was coated on the exposed PECVD silicon dioxide surface to promote cell growth. Immortalized mouse hypothalamic neurons (GT1-7) were cultured in vitro on the chip, and patterned cells were fluorescently stained and visualized by fluorescence microscopy. By our method, hydrophobic and hydrophilic regions can be reliably generated and easily visualized under a microscope prior to cell culturing. Cell growth was precisely controlled and limited to specific areas. The achieved resolution was 2 microns, and it could be improved with high resolution photolithographic methods.

  10. The Too-Much-Precision Effect.

    PubMed

    Loschelder, David D; Friese, Malte; Schaerer, Michael; Galinsky, Adam D

    2016-12-01

    Past research has suggested a fundamental principle of price precision: The more precise an opening price, the more it anchors counteroffers. The present research challenges this principle by demonstrating a too-much-precision effect. Five experiments (involving 1,320 experts and amateurs in real-estate, jewelry, car, and human-resources negotiations) showed that increasing the precision of an opening offer had positive linear effects for amateurs but inverted-U-shaped effects for experts. Anchor precision backfired because experts saw too much precision as reflecting a lack of competence. This negative effect held unless first movers gave rationales that boosted experts' perception of their competence. Statistical mediation and experimental moderation established the critical role of competence attributions. This research disentangles competing theoretical accounts (attribution of competence vs. scale granularity) and qualifies two putative truisms: that anchors affect experts and amateurs equally, and that more precise prices are linearly more potent anchors. The results refine current theoretical understanding of anchoring and have significant implications for everyday life.

  11. Evaluating measurements of carbon dioxide emissions using a precision source--A natural gas burner.

    PubMed

    Bryant, Rodney; Bundy, Matthew; Zong, Ruowen

    2015-07-01

    A natural gas burner has been used as a precise and accurate source for generating large quantities of carbon dioxide (CO2) to evaluate emissions measurements at near-industrial scale. Two methods for determining carbon dioxide emissions from stationary sources are considered here: predicting emissions based on fuel consumption measurements-predicted emissions measurements, and direct measurement of emissions quantities in the flue gas-direct emissions measurements. Uncertainty for the predicted emissions measurement was estimated at less than 1%. Uncertainty estimates for the direct emissions measurement of carbon dioxide were on the order of ±4%. The relative difference between the direct emissions measurements and the predicted emissions measurements was within the range of the measurement uncertainty, therefore demonstrating good agreement. The study demonstrates how independent methods are used to validate source emissions measurements, while also demonstrating how a fire research facility can be used as a precision test-bed to evaluate and improve carbon dioxide emissions measurements from stationary sources. Fossil-fuel-consuming stationary sources such as electric power plants and industrial facilities account for more than half of the CO2 emissions in the United States. Therefore, accurate emissions measurements from these sources are critical for evaluating efforts to reduce greenhouse gas emissions. This study demonstrates how a surrogate for a stationary source, a fire research facility, can be used to evaluate the accuracy of measurements of CO2 emissions.

  12. Precise determination of protein extinction coefficients under native and denaturing conditions using SV-AUC.

    PubMed

    Hoffmann, Andreas; Grassl, Kerstin; Gommert, Janine; Schlesak, Christian; Bepperling, Alexander

    2018-04-17

    The accurate determination of protein concentration is an important though non-trivial task during the development of a biopharmaceutical. The fundamental prerequisite for this is the availability of an accurate extinction coefficient. Common approaches for the determination of an extinction coefficient for a given protein are either based on the theoretical prediction utilizing the amino acid sequence or the photometric determination combined with a measurement of absolute protein concentration. Here, we report on an improved SV-AUC based method utilizing an analytical ultracentrifuge equipped with absorbance and Rayleigh interference optics. Global fitting of datasets helped to overcome some of the obstacles encountered with the traditional method employing synthetic boundary cells. Careful calculation of dn/dc values taking glycosylation and solvent composition into account allowed the determination of the extinction coefficients of monoclonal antibodies and an Fc-fusion protein under native as well as under denaturing conditions. An intra-assay precision of 0.9% and an accuracy of 1.8% compared to the theoretical value was achieved for monoclonal antibodies. Due to the large number of data points of a single dataset, no meaningful difference between the ProteomeLab XL-I and the new Optima AUC platform could be observed. Thus, the AUC-based approach offers a precise, convenient and versatile alternative to conventional methods like total amino acid analysis (AAA).

  13. Precise orbit determination based on raw GPS measurements

    NASA Astrophysics Data System (ADS)

    Zehentner, Norbert; Mayer-Gürr, Torsten

    2016-03-01

    Precise orbit determination is an essential part of the most scientific satellite missions. Highly accurate knowledge of the satellite position is used to geolocate measurements of the onboard sensors. For applications in the field of gravity field research, the position itself can be used as observation. In this context, kinematic orbits of low earth orbiters (LEO) are widely used, because they do not include a priori information about the gravity field. The limiting factor for the achievable accuracy of the gravity field through LEO positions is the orbit accuracy. We make use of raw global positioning system (GPS) observations to estimate the kinematic satellite positions. The method is based on the principles of precise point positioning. Systematic influences are reduced by modeling and correcting for all known error sources. Remaining effects such as the ionospheric influence on the signal propagation are either unknown or not known to a sufficient level of accuracy. These effects are modeled as unknown parameters in the estimation process. The redundancy in the adjustment is reduced; however, an improvement in orbit accuracy leads to a better gravity field estimation. This paper describes our orbit determination approach and its mathematical background. Some examples of real data applications highlight the feasibility of the orbit determination method based on raw GPS measurements. Its suitability for gravity field estimation is presented in a second step.

  14. Precision Optics Curriculum.

    ERIC Educational Resources Information Center

    Reid, Robert L.; And Others

    This guide outlines the competency-based, two-year precision optics curriculum that the American Precision Optics Manufacturers Association has proposed to fill the void that it suggests will soon exist as many of the master opticians currently employed retire. The model, which closely resembles the old European apprenticeship model, calls for 300…

  15. Improving precision of glomerular filtration rate estimating model by ensemble learning.

    PubMed

    Liu, Xun; Li, Ningshan; Lv, Linsheng; Fu, Yongmei; Cheng, Cailian; Wang, Caixia; Ye, Yuqiu; Li, Shaomin; Lou, Tanqi

    2017-11-09

    Accurate assessment of kidney function is clinically important, but estimates of glomerular filtration rate (GFR) by regression are imprecise. We hypothesized that ensemble learning could improve precision. A total of 1419 participants were enrolled, with 1002 in the development dataset and 417 in the external validation dataset. GFR was independently estimated from age, sex and serum creatinine using an artificial neural network (ANN), support vector machine (SVM), regression, and ensemble learning. GFR was measured by 99mTc-DTPA renal dynamic imaging calibrated with dual plasma sample 99mTc-DTPA GFR. Mean measured GFRs were 70.0 ml/min/1.73 m 2 in the developmental and 53.4 ml/min/1.73 m 2 in the external validation cohorts. In the external validation cohort, precision was better in the ensemble model of the ANN, SVM and regression equation (IQR = 13.5 ml/min/1.73 m 2 ) than in the new regression model (IQR = 14.0 ml/min/1.73 m 2 , P < 0.001). The precision of ensemble learning was the best of the three models, but the models had similar bias and accuracy. The median difference ranged from 2.3 to 3.7 ml/min/1.73 m 2 , 30% accuracy ranged from 73.1 to 76.0%, and P was > 0.05 for all comparisons of the new regression equation and the other new models. An ensemble learning model including three variables, the average ANN, SVM, and regression equation values, was more precise than the new regression model. A more complex ensemble learning strategy may further improve GFR estimates.

  16. THE MIRA–TITAN UNIVERSE: PRECISION PREDICTIONS FOR DARK ENERGY SURVEYS

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

    Heitmann, Katrin; Habib, Salman; Biswas, Rahul

    2016-04-01

    Large-scale simulations of cosmic structure formation play an important role in interpreting cosmological observations at high precision. The simulations must cover a parameter range beyond the standard six cosmological parameters and need to be run at high mass and force resolution. A key simulation-based task is the generation of accurate theoretical predictions for observables using a finite number of simulation runs, via the method of emulation. Using a new sampling technique, we explore an eight-dimensional parameter space including massive neutrinos and a variable equation of state of dark energy. We construct trial emulators using two surrogate models (the linear powermore » spectrum and an approximate halo mass function). The new sampling method allows us to build precision emulators from just 26 cosmological models and to systematically increase the emulator accuracy by adding new sets of simulations in a prescribed way. Emulator fidelity can now be continuously improved as new observational data sets become available and higher accuracy is required. Finally, using one ΛCDM cosmology as an example, we study the demands imposed on a simulation campaign to achieve the required statistics and accuracy when building emulators for investigations of dark energy.« less

  17. The mira-titan universe. Precision predictions for dark energy surveys

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

    Heitmann, Katrin; Bingham, Derek; Lawrence, Earl

    2016-03-28

    Large-scale simulations of cosmic structure formation play an important role in interpreting cosmological observations at high precision. The simulations must cover a parameter range beyond the standard six cosmological parameters and need to be run at high mass and force resolution. A key simulation-based task is the generation of accurate theoretical predictions for observables using a finite number of simulation runs, via the method of emulation. Using a new sampling technique, we explore an eight-dimensional parameter space including massive neutrinos and a variable equation of state of dark energy. We construct trial emulators using two surrogate models (the linear powermore » spectrum and an approximate halo mass function). The new sampling method allows us to build precision emulators from just 26 cosmological models and to systematically increase the emulator accuracy by adding new sets of simulations in a prescribed way. Emulator fidelity can now be continuously improved as new observational data sets become available and higher accuracy is required. Finally, using one ΛCDM cosmology as an example, we study the demands imposed on a simulation campaign to achieve the required statistics and accuracy when building emulators for investigations of dark energy.« less

  18. No Galaxy Left Behind: Accurate Measurements with the Faintest Objects in the Dark Energy Survey

    DOE PAGES

    Suchyta, E.

    2016-01-27

    Accurate statistical measurement with large imaging surveys has traditionally required throwing away a sizable fraction of the data. This is because most measurements have have relied on selecting nearly complete samples, where variations in the composition of the galaxy population with seeing, depth, or other survey characteristics are small. We introduce a new measurement method that aims to minimize this wastage, allowing precision measurement for any class of stars or galaxies detectable in an imaging survey. We have implemented our proposal in Balrog, a software package which embeds fake objects in real imaging in order to accurately characterize measurement biases.more » We also demonstrate this technique with an angular clustering measurement using Dark Energy Survey (DES) data. We first show that recovery of our injected galaxies depends on a wide variety of survey characteristics in the same way as the real data. We then construct a flux-limited sample of the faintest galaxies in DES, chosen specifically for their sensitivity to depth and seeing variations. Using the synthetic galaxies as randoms in the standard LandySzalay correlation function estimator suppresses the effects of variable survey selection by at least two orders of magnitude. Now our measured angular clustering is found to be in excellent agreement with that of a matched sample drawn from much deeper, higherresolution space-based COSMOS imaging; over angular scales of 0.004° < θ < 0.2 ° , we find a best-fit scaling amplitude between the DES and COSMOS measurements of 1.00 ± 0.09. We expect this methodology to be broadly useful for extending the statistical reach of measurements in a wide variety of coming imaging surveys.« less

  19. Precise comparisons of bottom-pressure and altimetric ocean tides

    NASA Astrophysics Data System (ADS)

    Ray, R. D.

    2013-09-01

    A new set of pelagic tide determinations is constructed from seafloor pressure measurements obtained at 151 sites in the deep ocean. To maximize precision of estimated tides, only stations with long time series are used; median time series length is 567 days. Geographical coverage is considerably improved by use of the international tsunami network, but coverage in the Indian Ocean and South Pacific is still weak. As a tool for assessing global ocean tide models, the data set is considerably more reliable than older data sets: the root-mean-square difference with a recent altimetric tide model is approximately 5 mm for the M2 constituent. Precision is sufficiently high to allow secondary effects in altimetric and bottom-pressure tide differences to be studied. The atmospheric tide in bottom pressure is clearly detected at the S1, S2, and T2 frequencies. The altimetric tide model is improved if satellite altimetry is corrected for crustal loading by the atmospheric tide. Models of the solid body tide can also be constrained. The free core-nutation effect in the K1 Love number is easily detected, but the overall estimates are not as accurate as a recent determination with very long baseline interferometry.

  20. Precision Stellar and Planetary Astrophysics with TESS and Gaia

    NASA Astrophysics Data System (ADS)

    Stevens, Daniel J.; KELT Collaboration

    2018-01-01

    There is an ever-present need for precise and accurate stellar parameters, particularly for low-mass stars. For example, some fraction of measured M dwarf radii are inflated and have effective temperatures that are suppressed relative to predictions from models, but the physical cause of these effects is still uncertain. This is exacerbated by the fact that only a handful of M dwarfs -- all from double-lined eclipsing binaries (EBs) -- have both masses and radii measured to 3% or better. In the Gaia era, we can now measure model-independent masses and radii for single-lined EBs, thus expanding the sample of stars with precisely measured parameters by at least an order of magnitude, in principle. I will illustrate how one can combine Gaia parallaxes and broad-band stellar fluxes with the eclipse and radial velocity data to provide model-independent masses and radii. I will present our expected achievable constraints on the masses and radii of single-lined EBs. I will discuss both our current effort to turn several dozens of single-lined EBs discovered by the KELT and HATNet surveys into a catalog of exquisitely characterized stars and exoplanets as well as the prospects for achieving similar science for a much larger number of systems with TESS.

  1. Precise Comparisons of Bottom-Pressure and Altimetric Ocean Tides

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.

    2013-01-01

    A new set of pelagic tide determinations is constructed from seafloor pressure measurements obtained at 151 sites in the deep ocean. To maximize precision of estimated tides, only stations with long time series are used; median time series length is 567 days. Geographical coverage is considerably improved by use of the international tsunami network, but coverage in the Indian Ocean and South Pacific is still weak. As a tool for assessing global ocean tide models, the data set is considerably more reliable than older data sets : the root-mean-square difference with a recent altimetric tide model is approximately 5 mm for the M2 constituent. Precision is sufficiently high to allow secondary effects in altimetric and bottom-pressure tide differences to be studied. The atmospheric tide in bottom pressure is clearly detected at the S1, S2, and T2 frequencies. The altimetric tide model is improved if satellite altimetry is corrected for crustal loading by the atmospheric tide. Models of the solid body tide can also be constrained. The free corenutation effect in the K1 Love number is easily detected, but the overall estimates are not as accurate as a recent determination with very long baseline interferometry.

  2. Human genomics projects and precision medicine.

    PubMed

    Carrasco-Ramiro, F; Peiró-Pastor, R; Aguado, B

    2017-09-01

    The completion of the Human Genome Project (HGP) in 2001 opened the floodgates to a deeper understanding of medicine. There are dozens of HGP-like projects which involve from a few tens to several million genomes currently in progress, which vary from having specialized goals or a more general approach. However, data generation, storage, management and analysis in public and private cloud computing platforms have raised concerns about privacy and security. The knowledge gained from further research has changed the field of genomics and is now slowly permeating into clinical medicine. The new precision (personalized) medicine, where genome sequencing and data analysis are essential components, allows tailored diagnosis and treatment according to the information from the patient's own genome and specific environmental factors. P4 (predictive, preventive, personalized and participatory) medicine is introducing new concepts, challenges and opportunities. This review summarizes current sequencing technologies, concentrates on ongoing human genomics projects, and provides some examples in which precision medicine has already demonstrated clinical impact in diagnosis and/or treatment.

  3. Pulse oximeter accuracy and precision affected by sensor location in cyanotic children.

    PubMed

    Sedaghat-Yazdi, Farshad; Torres, Adalberto; Fortuna, Randall; Geiss, Dale M

    2008-07-01

    Children's digits are often too small for proper attachment of oximeter sensors, necessitating sensor placement on the sole of the foot or palm of the hand. No study has determined what effect these sensor locations have on the accuracy and precision of this technology. The objective of this study was to assess the effect of sensor location on pulse oximeter accuracy (i.e., bias) and precision in critically ill children. Prospective, observational study with consecutive sampling. Tertiary care, pediatric intensive care unit. Fifty critically ill children, newborn to 2 yrs of age, with an indwelling arterial catheter. Forty-seven of 50 (94%) patients were postcardiac surgery. None. Co-oximeter-measured arterial oxygen saturation (Sao2) was compared with simultaneously obtained pulse oximetry saturations (Spo2). A total of 98 measurements were obtained, 48 measurements in the upper extremities (finger and palm) and 50 measurements in the lower extremities (toe and sole). The median Sao2 was 92% (66% to 100%). There was a significant difference in bias (i.e., average Spo2 - Sao2) and precision (+/-1 sd) when the sole and toe were compared (sole, 2.9 +/- 3.9 vs. toe, 1.6 +/- 2.2, p = .02) but no significant difference in bias and precision between the palm and the finger (palm, 1.4 +/- 3.2 vs. finger, 1.2 +/- 2.3, p = .99). There was a significant difference in bias +/- precision when the Sao2 was <90% compared with when Sao2 was >or=90% in the sole (6.0 +/- 5.7 vs. 1.8 +/- 2.1, p = .002) and palm (4.5 +/- 4.5 vs. 0.7 +/- 2.4, p = .006) but no significant difference in the finger (1.8 +/- 3.8 vs. 1.1 +/- 1.8, p = .95) or toe (1.9 +/- 2.9 vs. 1.6 +/- 1.9, p = .65). The Philips M1020A pulse oximeter and Nellcor MAX-N sensors were less accurate and precise when used on the sole of the foot or palm of the hand of a child with an Sao2 <90%.

  4. Production of zinc oxide nanowires power with precisely defined morphology

    NASA Astrophysics Data System (ADS)

    Mičová, Júlia; Remeš, Zdeněk; Chan, Yu-Ying

    2017-12-01

    The interest about zinc oxide is increasing thanks to its unique chemical and physical properties. Our attention has focused on preparation powder of 1D nanostructures of ZnO nanowires with precisely defined morphology include characterization size (length and diameter) and shape controlled in the scanning electron microscopy (SEM). We have compared results of SEM with dynamic light scattering (DLS) technique. We have found out that SEM method gives more accurate results. We have proposed transformation process from ZnO nanowires on substrates to ZnO nanowires powder by ultrasound peeling to colloid followed by lyophilization. This method of the mass production of the ZnO nanowires powder has some advantages: simplicity, cost effective, large-scale and environment friendly.

  5. Precision medicine in cardiology.

    PubMed

    Antman, Elliott M; Loscalzo, Joseph

    2016-10-01

    The cardiovascular research and clinical communities are ideally positioned to address the epidemic of noncommunicable causes of death, as well as advance our understanding of human health and disease, through the development and implementation of precision medicine. New tools will be needed for describing the cardiovascular health status of individuals and populations, including 'omic' data, exposome and social determinants of health, the microbiome, behaviours and motivations, patient-generated data, and the array of data in electronic medical records. Cardiovascular specialists can build on their experience and use precision medicine to facilitate discovery science and improve the efficiency of clinical research, with the goal of providing more precise information to improve the health of individuals and populations. Overcoming the barriers to implementing precision medicine will require addressing a range of technical and sociopolitical issues. Health care under precision medicine will become a more integrated, dynamic system, in which patients are no longer a passive entity on whom measurements are made, but instead are central stakeholders who contribute data and participate actively in shared decision-making. Many traditionally defined diseases have common mechanisms; therefore, elimination of a siloed approach to medicine will ultimately pave the path to the creation of a universal precision medicine environment.

  6. Laser-generated ultrasound for high-precision cutting of tissue-mimicking gels (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Lee, Taehwa; Luo, Wei; Li, Qiaochu; Guo, L. Jay

    2017-03-01

    Laser-generated focused ultrasound has shown great promise in precisely treating cells and tissues by producing controlled micro-cavitation within the acoustic focal volume (<100 um). However, the previous demonstration used cells and tissues cultured on glass substrates. The glass substrates were found to be critical to cavitation, because ultrasound amplitude doubles due to the reflection from the substrate, thus allowing for reaching pressure amplitude to cavitation threshold. In other words, without the sound reflecting substrate, pressure amplitude may not be strong enough to create cavitation, thus limiting its application to only cultured biomaterials on the rigid substrates. By using laser-generated focused ultrasound without relying on sound-reflecting substrates, we demonstrate free-field cavitation in water and its application to high-precision cutting of tissue-mimicking gels. In the absence of a rigid boundary, strong pressure for cavitation was enabled by recently optimized photoacoustic lens with increased focal gain (>30 MPa, negative pressure amplitude). By moving cavitation spots along pre-defined paths through a motorized stage, tissue-mimicking gels of different elastic moduli were cut into different shapes (rectangle, triangle, and circle), leaving behind the same shape of holes, whose sizes are less than 1 mm. The cut line width is estimated to be less than 50 um (corresponding to localized cavitation region), allowing for accurate cutting. This novel approach could open new possibility for in-vivo treatment of diseased tissues in a high-precision manner (i.e., high-precision invisible sonic scalpel).

  7. Induced Pluripotent Stem Cells: at the Heart of Cardiovascular Precision Medicine

    PubMed Central

    Chen, Ian Y.; Matsa, Elena; Wu, Joseph C.

    2018-01-01

    The advent of human induced pluripotent stem cell (hiPSC) technology has revitalized much of the efforts within the past decade to more fully realize the potential of human embryonic stem cells (hESCs). Adding to the possibility of generating unlimited supplies of any cell types of interest, the hiPSC technology now enables the derivation of cells with patient-specific phenotypes. With the Precision Medicine Initiative, it is clear that the hiPSC technology will play a vital role in the advancement of cardiovascular research and medicine. This review summarizes the tremendous and continuing progress that has been made in the field of hiPSC technology, with particular emphasis on cardiovascular disease modeling and drug development. Wherever appropriate, the growing roles of hiPSC technology in the practice of precision medicine will be specifically discussed. PMID:27009425

  8. Precise measurement of the performance of thermoelectric modules

    NASA Astrophysics Data System (ADS)

    Díaz-Chao, Pablo; Muñiz-Piniella, Andrés; Selezneva, Ekaterina; Cuenat, Alexandre

    2016-08-01

    The potential exploitation of thermoelectric modules into mass market applications such as exhaust gas heat recovery in combustion engines requires an accurate knowledge of their performance. Further expansion of the market will also require confidence on the results provided by suppliers to end-users. However, large variation in performance and maximum operating point is observed for identical modules when tested by different laboratories. Here, we present the first metrological study of the impact of mounting and testing procedures on the precision of thermoelectric modules measurement. Variability in the electrical output due to mechanical pressure or type of thermal interface materials is quantified for the first time. The respective contribution of the temperature difference and the mean temperature to the variation in the output performance is quantified. The contribution of these factors to the total uncertainties in module characterisation is detailed.

  9. Precision measurement of the three 2(3)P(J) helium fine structure intervals.

    PubMed

    Zelevinsky, T; Farkas, D; Gabrielse, G

    2005-11-11

    The three 2(3)P fine structure intervals of 4H are measured at an improved accuracy that is sufficient to test two-electron QED theory and to determine the fine structure constant alpha to 14 parts in 10(9). The more accurate determination of alpha, to a precision higher than attained with the quantum Hall and Josephson effects, awaits the reconciliation of two inconsistent theoretical calculations now being compared term by term. A low pressure helium discharge presents experimental uncertainties quite different than for earlier measurements and allows direct measurements of light pressure shifts.

  10. Integration of radar altimeter, precision navigation, and digital terrain data for low-altitude flight

    NASA Technical Reports Server (NTRS)

    Zelenka, Richard E.

    1992-01-01

    Avionic systems that depend on digitized terrain elevation data for guidance generation or navigational reference require accurate absolute and relative distance measurements to the terrain, especially as they approach lower altitudes. This is particularly exacting in low-altitude helicopter missions, where aggressive terrain hugging maneuvers create minimal horizontal and vertical clearances and demand precise terrain positioning. Sole reliance on airborne precision navigation and stored terrain elevation data for above-ground-level (AGL) positioning severely limits the operational altitude of such systems. A Kalman filter is presented which blends radar altimeter returns, precision navigation, and stored terrain elevation data for AGL positioning. The filter is evaluated using low-altitude helicopter flight test data acquired over moderately rugged terrain. The proposed Kalman filter is found to remove large disparities in predicted AGL altitude (i.e., from airborne navigation and terrain elevation data) in the presence of measurement anomalies and dropouts. Previous work suggested a minimum clearance altitude of 220 ft AGL for a near-terrain guidance system; integration of a radar altimeter allows for operation of that system below 50 ft, subject to obstacle-avoidance limitations.

  11. Motor imagery training improves precision of an upper limb movement in patients with hemiparesis.

    PubMed

    Grabherr, Luzia; Jola, Corinne; Berra, Gilberto; Theiler, Robert; Mast, Fred W

    2015-01-01

    In healthy participants, beneficial effects of motor imagery training on movement execution have been shown for precision, strength, and speed. In the clinical context, it is still debated whether motor imagery provides an effective rehabilitation technique in patients with motor deficits. To compare the effectiveness of two different types of movement training: motor imagery vs. motor execution. Twenty-five patients with hemiparesis were assigned to one of two training groups: the imagery or the execution-training group. Both groups completed a baseline test before they received six training sessions, each of which was followed by a test session. Using a novel and precisely quantifiable test, we assessed how accurately patients performed an upper limb movement. Both training groups improved performance over the six test sessions but the improvement was significantly larger in the imagery group. That is, the imagery group was able to perform more precise movements than the execution group after the sixth training session while there was no difference at the beginning of the training. The results provide evidence for the benefit of motor imagery training in patients with hemiparesis and thus suggest the integration of cognitive training in conventional physiotherapy practice.

  12. What makes an accurate and reliable subject-specific finite element model? A case study of an elephant femur

    PubMed Central

    Panagiotopoulou, O.; Wilshin, S. D.; Rayfield, E. J.; Shefelbine, S. J.; Hutchinson, J. R.

    2012-01-01

    Finite element modelling is well entrenched in comparative vertebrate biomechanics as a tool to assess the mechanical design of skeletal structures and to better comprehend the complex interaction of their form–function relationships. But what makes a reliable subject-specific finite element model? To approach this question, we here present a set of convergence and sensitivity analyses and a validation study as an example, for finite element analysis (FEA) in general, of ways to ensure a reliable model. We detail how choices of element size, type and material properties in FEA influence the results of simulations. We also present an empirical model for estimating heterogeneous material properties throughout an elephant femur (but of broad applicability to FEA). We then use an ex vivo experimental validation test of a cadaveric femur to check our FEA results and find that the heterogeneous model matches the experimental results extremely well, and far better than the homogeneous model. We emphasize how considering heterogeneous material properties in FEA may be critical, so this should become standard practice in comparative FEA studies along with convergence analyses, consideration of element size, type and experimental validation. These steps may be required to obtain accurate models and derive reliable conclusions from them. PMID:21752810

  13. Precision nutrition - review of methods for point-of-care assessment of nutritional status.

    PubMed

    Srinivasan, Balaji; Lee, Seoho; Erickson, David; Mehta, Saurabh

    2017-04-01

    Precision nutrition encompasses prevention and treatment strategies for optimizing health that consider individual variability in diet, lifestyle, environment and genes by accurately determining an individual's nutritional status. This is particularly important as malnutrition now affects a third of the global population, with most of those affected or their care providers having limited means of determining their nutritional status. Similarly, program implementers often have no way of determining the impact or success of their interventions, thus hindering their scale-up. Exciting new developments in the area of point-of-care diagnostics promise to provide improved access to nutritional status assessment, as a first step towards enabling precision nutrition and tailored interventions at both the individual and community levels. In this review, we focus on the current advances in developing portable diagnostics for assessment of nutritional status at point-of-care, along with the numerous design challenges in this process and potential solutions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Theranostics and metabolotheranostics for precision medicine in oncology

    NASA Astrophysics Data System (ADS)

    Bhujwalla, Zaver M.; Kakkad, Samata; Chen, Zhihang; Jin, Jiefu; Hapuarachchige, Sudath; Artemov, Dmitri; Penet, Marie-France

    2018-06-01

    Most diseases, especially cancer, would significantly benefit from precision medicine where treatment is shaped for the individual. The concept of theragnostics or theranostics emerged around 2002 to describe the incorporation of diagnostic assays into the selection of therapy for this purpose. Increasingly, theranostics has been used for strategies that combine noninvasive imaging-based diagnostics with therapy. Within the past decade theranostic imaging has transformed into a rapidly expanding field that is located at the interface of diagnosis and therapy. A critical need in cancer treatment is to minimize damage to normal tissue. Molecular imaging can be applied to identify targets specific to cancer with imaging, design agents against these targets to visualize their delivery, and monitor response to treatment, with the overall purpose of minimizing collateral damage. Genomic and proteomic profiling can provide an extensive 'fingerprint' of each tumor. With this cancer fingerprint, theranostic agents can be designed to personalize treatment for precision medicine of cancer, and minimize damage to normal tissue. Here, for the first time, we have introduced the term 'metabolotheranostics' to describe strategies where disease-based alterations in metabolic pathways detected by MRS are specifically targeted with image-guided delivery platforms to achieve disease-specific therapy. The versatility of MRI and MRS in molecular and functional imaging makes these technologies especially important in theranostic MRI and 'metabolotheranostics'. Our purpose here is to provide insights into the capabilities and applications of this exciting new field in cancer treatment with a focus on MRI and MRS.

  15. High-precision Ru isotopic measurements by multi-collector ICP-MS.

    PubMed

    Becker, Harry; Dalpe, Claude; Walker, Richard J

    2002-06-01

    Ruthenium isotopic data for a pure Aldrich ruthenium nitrate solution obtained using a Nu Plasma multi collector inductively coupled plasma-mass spectrometer (MC-ICP-MS) shows excellent agreement (better than 1 epsilon unit = 1 part in 10(4)) with data obtained by other techniques for the mass range between 96 and 101 amu. External precisions are at the 0.5-1.7 epsilon level (2sigma). Higher sensitivity for MC ICP-MS compared to negative thermal ionization mass spectrometry (N-TIMS) is offset by the uncertainties introduced by relatively large mass discrimination and instabilities in the plasma source-ion extraction region that affect the long-term reproducibility. Large mass bias correction in ICP mass spectrometry demands particular attention to be paid to the choice of normalizing isotopes. Because of its position in the mass spectrum and the large mass bias correction, obtaining precise and accurate abundance data for 104Ru by MC-ICP-MS remains difficult. Internal and external mass bias correction schemes in this mass range may show similar shortcomings if the isotope of interest does not lie within the mass range covered by the masses used for normalization. Analyses of meteorite samples show that if isobaric interferences from Mo are sufficiently large (Ru/Mo < 10(4)), uncertainties on the Mo interference correction propagate through the mass bias correction and yield inaccurate results for Ru isotopic compositions. Second-order linear corrections may be used to correct for these inaccuracies, but such results are generally less precise than N-TIMS data.

  16. Accurate Attitude Estimation Using ARS under Conditions of Vehicle Movement Based on Disturbance Acceleration Adaptive Estimation and Correction

    PubMed Central

    Xing, Li; Hang, Yijun; Xiong, Zhi; Liu, Jianye; Wan, Zhong

    2016-01-01

    This paper describes a disturbance acceleration adaptive estimate and correction approach for an attitude reference system (ARS) so as to improve the attitude estimate precision under vehicle movement conditions. The proposed approach depends on a Kalman filter, where the attitude error, the gyroscope zero offset error and the disturbance acceleration error are estimated. By switching the filter decay coefficient of the disturbance acceleration model in different acceleration modes, the disturbance acceleration is adaptively estimated and corrected, and then the attitude estimate precision is improved. The filter was tested in three different disturbance acceleration modes (non-acceleration, vibration-acceleration and sustained-acceleration mode, respectively) by digital simulation. Moreover, the proposed approach was tested in a kinematic vehicle experiment as well. Using the designed simulations and kinematic vehicle experiments, it has been shown that the disturbance acceleration of each mode can be accurately estimated and corrected. Moreover, compared with the complementary filter, the experimental results have explicitly demonstrated the proposed approach further improves the attitude estimate precision under vehicle movement conditions. PMID:27754469

  17. Accurate Attitude Estimation Using ARS under Conditions of Vehicle Movement Based on Disturbance Acceleration Adaptive Estimation and Correction.

    PubMed

    Xing, Li; Hang, Yijun; Xiong, Zhi; Liu, Jianye; Wan, Zhong

    2016-10-16

    This paper describes a disturbance acceleration adaptive estimate and correction approach for an attitude reference system (ARS) so as to improve the attitude estimate precision under vehicle movement conditions. The proposed approach depends on a Kalman filter, where the attitude error, the gyroscope zero offset error and the disturbance acceleration error are estimated. By switching the filter decay coefficient of the disturbance acceleration model in different acceleration modes, the disturbance acceleration is adaptively estimated and corrected, and then the attitude estimate precision is improved. The filter was tested in three different disturbance acceleration modes (non-acceleration, vibration-acceleration and sustained-acceleration mode, respectively) by digital simulation. Moreover, the proposed approach was tested in a kinematic vehicle experiment as well. Using the designed simulations and kinematic vehicle experiments, it has been shown that the disturbance acceleration of each mode can be accurately estimated and corrected. Moreover, compared with the complementary filter, the experimental results have explicitly demonstrated the proposed approach further improves the attitude estimate precision under vehicle movement conditions.

  18. Method to make accurate concentration and isotopic measurements for small gas samples

    NASA Astrophysics Data System (ADS)

    Palmer, M. R.; Wahl, E.; Cunningham, K. L.

    2013-12-01

    Carbon isotopic ratio measurements of CO2 and CH4 provide valuable insight into carbon cycle processes. However, many of these studies, like soil gas, soil flux, and water head space experiments, provide very small gas sample volumes, too small for direct measurement by current constant-flow Cavity Ring-Down (CRDS) isotopic analyzers. Previously, we addressed this issue by developing a sample introduction module which enabled the isotopic ratio measurement of 40ml samples or smaller. However, the system, called the Small Sample Isotope Module (SSIM), does dilute the sample during the delivery with inert carrier gas which causes a ~5% reduction in concentration. The isotopic ratio measurements are not affected by this small dilution, but researchers are naturally interested accurate concentration measurements. We present the accuracy and precision of a new method of using this delivery module which we call 'double injection.' Two portions of the 40ml of the sample (20ml each) are introduced to the analyzer, the first injection of which flushes out the diluting gas and the second injection is measured. The accuracy of this new method is demonstrated by comparing the concentration and isotopic ratio measurements for a gas sampled directly and that same gas measured through the SSIM. The data show that the CO2 concentration measurements were the same within instrument precision. The isotopic ratio precision (1σ) of repeated measurements was 0.16 permil for CO2 and 1.15 permil for CH4 at ambient concentrations. This new method provides a significant enhancement in the information provided by small samples.

  19. Accurate measurement of transgene copy number in crop plants using droplet digital PCR.

    PubMed

    Collier, Ray; Dasgupta, Kasturi; Xing, Yan-Ping; Hernandez, Bryan Tarape; Shao, Min; Rohozinski, Dominica; Kovak, Emma; Lin, Jeanie; de Oliveira, Maria Luiza P; Stover, Ed; McCue, Kent F; Harmon, Frank G; Blechl, Ann; Thomson, James G; Thilmony, Roger

    2017-06-01

    Genetic transformation is a powerful means for the improvement of crop plants, but requires labor- and resource-intensive methods. An efficient method for identifying single-copy transgene insertion events from a population of independent transgenic lines is desirable. Currently, transgene copy number is estimated by either Southern blot hybridization analyses or quantitative polymerase chain reaction (qPCR) experiments. Southern hybridization is a convincing and reliable method, but it also is expensive, time-consuming and often requires a large amount of genomic DNA and radioactively labeled probes. Alternatively, qPCR requires less DNA and is potentially simpler to perform, but its results can lack the accuracy and precision needed to confidently distinguish between one- and two-copy events in transgenic plants with large genomes. To address this need, we developed a droplet digital PCR-based method for transgene copy number measurement in an array of crops: rice, citrus, potato, maize, tomato and wheat. The method utilizes specific primers to amplify target transgenes, and endogenous reference genes in a single duplexed reaction containing thousands of droplets. Endpoint amplicon production in the droplets is detected and quantified using sequence-specific fluorescently labeled probes. The results demonstrate that this approach can generate confident copy number measurements in independent transgenic lines in these crop species. This method and the compendium of probes and primers will be a useful resource for the plant research community, enabling the simple and accurate determination of transgene copy number in these six important crop species. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  20. Generalization of the normal-exponential model: exploration of a more accurate parametrisation for the signal distribution on Illumina BeadArrays.

    PubMed

    Plancade, Sandra; Rozenholc, Yves; Lund, Eiliv

    2012-12-11

    Illumina BeadArray technology includes non specific negative control features that allow a precise estimation of the background noise. As an alternative to the background subtraction proposed in BeadStudio which leads to an important loss of information by generating negative values, a background correction method modeling the observed intensities as the sum of the exponentially distributed signal and normally distributed noise has been developed. Nevertheless, Wang and Ye (2012) display a kernel-based estimator of the signal distribution on Illumina BeadArrays and suggest that a gamma distribution would represent a better modeling of the signal density. Hence, the normal-exponential modeling may not be appropriate for Illumina data and background corrections derived from this model may lead to wrong estimation. We propose a more flexible modeling based on a gamma distributed signal and a normal distributed background noise and develop the associated background correction, implemented in the R-package NormalGamma. Our model proves to be markedly more accurate to model Illumina BeadArrays: on the one hand, it is shown on two types of Illumina BeadChips that this model offers a more correct fit of the observed intensities. On the other hand, the comparison of the operating characteristics of several background correction procedures on spike-in and on normal-gamma simulated data shows high similarities, reinforcing the validation of the normal-gamma modeling. The performance of the background corrections based on the normal-gamma and normal-exponential models are compared on two dilution data sets, through testing procedures which represent various experimental designs. Surprisingly, we observe that the implementation of a more accurate parametrisation in the model-based background correction does not increase the sensitivity. These results may be explained by the operating characteristics of the estimators: the normal-gamma background correction offers an improvement

  1. QuASAR-MPRA: accurate allele-specific analysis for massively parallel reporter assays.

    PubMed

    Kalita, Cynthia A; Moyerbrailean, Gregory A; Brown, Christopher; Wen, Xiaoquan; Luca, Francesca; Pique-Regi, Roger

    2018-03-01

    The majority of the human genome is composed of non-coding regions containing regulatory elements such as enhancers, which are crucial for controlling gene expression. Many variants associated with complex traits are in these regions, and may disrupt gene regulatory sequences. Consequently, it is important to not only identify true enhancers but also to test if a variant within an enhancer affects gene regulation. Recently, allele-specific analysis in high-throughput reporter assays, such as massively parallel reporter assays (MPRAs), have been used to functionally validate non-coding variants. However, we are still missing high-quality and robust data analysis tools for these datasets. We have further developed our method for allele-specific analysis QuASAR (quantitative allele-specific analysis of reads) to analyze allele-specific signals in barcoded read counts data from MPRA. Using this approach, we can take into account the uncertainty on the original plasmid proportions, over-dispersion, and sequencing errors. The provided allelic skew estimate and its standard error also simplifies meta-analysis of replicate experiments. Additionally, we show that a beta-binomial distribution better models the variability present in the allelic imbalance of these synthetic reporters and results in a test that is statistically well calibrated under the null. Applying this approach to the MPRA data, we found 602 SNPs with significant (false discovery rate 10%) allele-specific regulatory function in LCLs. We also show that we can combine MPRA with QuASAR estimates to validate existing experimental and computational annotations of regulatory variants. Our study shows that with appropriate data analysis tools, we can improve the power to detect allelic effects in high-throughput reporter assays. http://github.com/piquelab/QuASAR/tree/master/mpra. fluca@wayne.edu or rpique@wayne.edu. Supplementary data are available online at Bioinformatics. © The Author (2017). Published by

  2. A robust recognition and accurate locating method for circular coded diagonal target

    NASA Astrophysics Data System (ADS)

    Bao, Yunna; Shang, Yang; Sun, Xiaoliang; Zhou, Jiexin

    2017-10-01

    As a category of special control points which can be automatically identified, artificial coded targets have been widely developed in the field of computer vision, photogrammetry, augmented reality, etc. In this paper, a new circular coded target designed by RockeTech technology Corp. Ltd is analyzed and studied, which is called circular coded diagonal target (CCDT). A novel detection and recognition method with good robustness is proposed in the paper, and implemented on Visual Studio. In this algorithm, firstly, the ellipse features of the center circle are used for rough positioning. Then, according to the characteristics of the center diagonal target, a circular frequency filter is designed to choose the correct center circle and eliminates non-target noise. The precise positioning of the coded target is done by the correlation coefficient fitting extreme value method. Finally, the coded target recognition is achieved by decoding the binary sequence in the outer ring of the extracted target. To test the proposed algorithm, this paper has carried out simulation experiments and real experiments. The results show that the CCDT recognition and accurate locating method proposed in this paper can robustly recognize and accurately locate the targets in complex and noisy background.

  3. Predicted osteotomy planes are accurate when using patient-specific instrumentation for total knee arthroplasty in cadavers: a descriptive analysis.

    PubMed

    Kievit, A J; Dobbe, J G G; Streekstra, G J; Blankevoort, L; Schafroth, M U

    2018-06-01

    Malalignment of implants is a major source of failure during total knee arthroplasty. To achieve more accurate 3D planning and execution of the osteotomy cuts during surgery, the Signature (Biomet, Warsaw) patient-specific instrumentation (PSI) was used to produce pin guides for the positioning of the osteotomy blocks by means of computer-aided manufacture based on CT scan images. The research question of this study is: what is the transfer accuracy of osteotomy planes predicted by the Signature PSI system for preoperative 3D planning and intraoperative block-guided pin placement to perform total knee arthroplasty procedures? The transfer accuracy achieved by using the Signature PSI system was evaluated by comparing the osteotomy planes predicted preoperatively with the osteotomy planes seen intraoperatively in human cadaveric legs. Outcomes were measured in terms of translational and rotational errors (varus, valgus, flexion, extension and axial rotation) for both tibia and femur osteotomies. Average translational errors between the osteotomy planes predicted using the Signature system and the actual osteotomy planes achieved was 0.8 mm (± 0.5 mm) for the tibia and 0.7 mm (± 4.0 mm) for the femur. Average rotational errors in relation to predicted and achieved osteotomy planes were 0.1° (± 1.2°) of varus and 0.4° (± 1.7°) of anterior slope (extension) for the tibia, and 2.8° (± 2.0°) of varus and 0.9° (± 2.7°) of flexion and 1.4° (± 2.2°) of external rotation for the femur. The similarity between osteotomy planes predicted using the Signature system and osteotomy planes actually achieved was excellent for the tibia although some discrepancies were seen for the femur. The use of 3D system techniques in TKA surgery can provide accurate intraoperative guidance, especially for patients with deformed bone, tailored to individual patients and ensure better placement of the implant.

  4. Precision medicine in oncology: New practice models and roles for oncology pharmacists.

    PubMed

    Walko, Christine; Kiel, Patrick J; Kolesar, Jill

    2016-12-01

    Three different precision medicine practice models developed by oncology pharmacists are described, including strategies for implementation and recommendations for educating the next generation of oncology pharmacy practitioners. Oncology is unique in that somatic mutations can both drive the development of a tumor and serve as a therapeutic target for treating the cancer. Precision medicine practice models are a forum through which interprofessional teams, including pharmacists, discuss tumor somatic mutations to guide patient-specific treatment. The University of Wisconsin, Indiana University, and Moffit Cancer Center have implemented precision medicine practice models developed and led by oncology pharmacists. Different practice models, including a clinic, a clinical consultation service, and a molecular tumor board (MTB), were adopted to enhance integration into health systems and payment structures. Although the practice models vary, commonalities of three models include leadership by the clinical pharmacist, specific therapeutic recommendations, procurement of medications for off-label use, and a research component. These three practice models function as interprofessional training sites for pharmacy and medical students and residents, providing an important training resource at these institutions. Key implementation strategies include interprofessional involvement, institutional support, integration into clinical workflow, and selection of model by payer mix. MTBs are a pathway for clinical implementation of genomic medicine in oncology and are an emerging practice model for oncology pharmacists. Because pharmacists must be prepared to participate fully in contemporary practice, oncology pharmacy residents must be trained in genomic oncology, schools of pharmacy should expand precision medicine and genomics education, and opportunities for continuing education in precision medicine should be made available to practicing pharmacists. Copyright © 2016 by the

  5. Precision of working memory for visual motion sequences and transparent motion surfaces.

    PubMed

    Zokaei, Nahid; Gorgoraptis, Nikos; Bahrami, Bahador; Bays, Paul M; Husain, Masud

    2011-12-01

    Recent studies investigating working memory for location, color, and orientation support a dynamic resource model. We examined whether this might also apply to motion, using random dot kinematograms (RDKs) presented sequentially or simultaneously. Mean precision for motion direction declined as sequence length increased, with precision being lower for earlier RDKs. Two alternative models of working memory were compared specifically to distinguish between the contributions of different sources of error that corrupt memory (W. Zhang & S. J. Luck, 2008 vs. P. M. Bays, R. F. G. Catalao, & M. Husain, 2009). The latter provided a significantly better fit for the data, revealing that decrease in memory precision for earlier items is explained by an increase in interference from other items in a sequence rather than random guessing or a temporal decay of information. Misbinding feature attributes is an important source of error in working memory. Precision of memory for motion direction decreased when two RDKs were presented simultaneously as transparent surfaces, compared to sequential RDKs. However, precision was enhanced when one motion surface was prioritized, demonstrating that selective attention can improve recall precision. These results are consistent with a resource model that can be used as a general conceptual framework for understanding working memory across a range of visual features.

  6. Precision of working memory for visual motion sequences and transparent motion surfaces

    PubMed Central

    Zokaei, Nahid; Gorgoraptis, Nikos; Bahrami, Bahador; Bays, Paul M; Husain, Masud

    2012-01-01

    Recent studies investigating working memory for location, colour and orientation support a dynamic resource model. We examined whether this might also apply to motion, using random dot kinematograms (RDKs) presented sequentially or simultaneously. Mean precision for motion direction declined as sequence length increased, with precision being lower for earlier RDKs. Two alternative models of working memory were compared specifically to distinguish between the contributions of different sources of error that corrupt memory (Zhang & Luck (2008) vs. Bays et al (2009)). The latter provided a significantly better fit for the data, revealing that decrease in memory precision for earlier items is explained by an increase in interference from other items in a sequence, rather than random guessing or a temporal decay of information. Misbinding feature attributes is an important source of error in working memory. Precision of memory for motion direction decreased when two RDKs were presented simultaneously as transparent surfaces, compared to sequential RDKs. However, precision was enhanced when one motion surface was prioritized, demonstrating that selective attention can improve recall precision. These results are consistent with a resource model that can be used as a general conceptual framework for understanding working memory across a range of visual features. PMID:22135378

  7. High-precision timeline for Earth’s most severe extinction

    PubMed Central

    Burgess, Seth D.; Bowring, Samuel; Shen, Shu-zhong

    2014-01-01

    The end-Permian mass extinction was the most severe loss of marine and terrestrial biota in the last 542 My. Understanding its cause and the controls on extinction/recovery dynamics depends on an accurate and precise age model. U-Pb zircon dates for five volcanic ash beds from the Global Stratotype Section and Point for the Permian-Triassic boundary at Meishan, China, define an age model for the extinction and allow exploration of the links between global environmental perturbation, carbon cycle disruption, mass extinction, and recovery at millennial timescales. The extinction occurred between 251.941 ± 0.037 and 251.880 ± 0.031 Mya, an interval of 60 ± 48 ka. Onset of a major reorganization of the carbon cycle immediately precedes the initiation of extinction and is punctuated by a sharp (3‰), short-lived negative spike in the isotopic composition of carbonate carbon. Carbon cycle volatility persists for ∼500 ka before a return to near preextinction values. Decamillenial to millennial level resolution of the mass extinction and its aftermath will permit a refined evaluation of the relative roles of rate-dependent processes contributing to the extinction, allowing insight into postextinction ecosystem expansion, and establish an accurate time point for evaluating the plausibility of trigger and kill mechanisms. PMID:24516148

  8. Precision phenotyping of epicuticular waxes associated with insect resistance

    USDA-ARS?s Scientific Manuscript database

    Accurate phenotyping is imperative for linkage mapping and association genetics. Amounts and types of epicuticular waxes on the leaf surface are important for plant-insect interactions. In onion, specific wax profiles are associated with resistance to the insect pest Thrips tabaci. Epicuticular wax ...

  9. Accurate differentiation of Mycobacterium chimaera from Mycobacterium intracellulare by MALDI-TOF MS analysis.

    PubMed

    Pranada, Arthur B; Witt, Ellen; Bienia, Michael; Kostrzewa, Markus; Timke, Markus

    2017-05-01

    The increasing number of infections caused by nontuberculous mycobacteria (NTM) has prompted the need for rapid and precise identification methods of these pathogens. Several studies report the applicability of MALDI-TOF mass spectrometry (MS) for identification of NTM. However, some closely related species have very similar spectral mass fingerprints, and until recently, Mycobacterium chimaera and M. intracellulare could not be separated from each other by MALDI-TOF MS. The conventional identification methods used in routine diagnostics have similar limitations. Recently, the differentiation of these two species within the Mycobacterium avium complex has become increasingly important due to reports of M. chimaera infections related to open heart surgery in Europe and in the USA. In this report, a method for the distinct differentiation of M. chimaera and M. intracellulare using a more detailed analysis of MALDI-TOF mass spectra is presented. Species-specific peaks could be identified and it was possible to assign all isolates (100 %) from reference strain collections as well as clinical isolates to the correct species. We have developed a model for the accurate identification of M. chimaera and M. intracellulare by MALDI-TOF MS. This approach has the potential for routine use in microbiology laboratories, as the model itself can be easily implemented into the software of the currently available systems by MALDI-TOF MS manufacturers.

  10. Optimetrics for Precise Navigation

    NASA Technical Reports Server (NTRS)

    Yang, Guangning; Heckler, Gregory; Gramling, Cheryl

    2017-01-01

    Optimetrics for Precise Navigation will be implemented on existing optical communication links. The ranging and Doppler measurements are conducted over communication data frame and clock. The measurement accuracy is two orders of magnitude better than TDRSS. It also has other advantages of: The high optical carrier frequency enables: (1) Immunity from ionosphere and interplanetary Plasma noise floor, which is a performance limitation for RF tracking; and (2) High antenna gain reduces terminal size and volume, enables high precision tracking in Cubesat, and in deep space smallsat. High Optical Pointing Precision provides: (a) spacecraft orientation, (b) Minimal additional hardware to implement Precise Optimetrics over optical comm link; and (c) Continuous optical carrier phase measurement will enable the system presented here to accept future optical frequency standard with much higher clock accuracy.

  11. Precision and accuracy of 3D lower extremity residua measurement systems

    NASA Astrophysics Data System (ADS)

    Commean, Paul K.; Smith, Kirk E.; Vannier, Michael W.; Hildebolt, Charles F.; Pilgram, Thomas K.

    1996-04-01

    Accurate and reproducible geometric measurement of lower extremity residua is required for custom prosthetic socket design. We compared spiral x-ray computed tomography (SXCT) and 3D optical surface scanning (OSS) with caliper measurements and evaluated the precision and accuracy of each system. Spiral volumetric CT scanned surface and subsurface information was used to make external and internal measurements, and finite element models (FEMs). SXCT and OSS were used to measure lower limb residuum geometry of 13 below knee (BK) adult amputees. Six markers were placed on each subject's BK residuum and corresponding plaster casts and distance measurements were taken to determine precision and accuracy for each system. Solid models were created from spiral CT scan data sets with the prosthesis in situ under different loads using p-version finite element analysis (FEA). Tissue properties of the residuum were estimated iteratively and compared with values taken from the biomechanics literature. The OSS and SXCT measurements were precise within 1% in vivo and 0.5% on plaster casts, and accuracy was within 3.5% in vivo and 1% on plaster casts compared with caliper measures. Three-dimensional optical surface and SXCT imaging systems are feasible for capturing the comprehensive 3D surface geometry of BK residua, and provide distance measurements statistically equivalent to calipers. In addition, SXCT can readily distinguish internal soft tissue and bony structure of the residuum. FEM can be applied to determine tissue material properties interactively using inverse methods.

  12. Ethical considerations of neuro-oncology trial design in the era of precision medicine.

    PubMed

    Gupta, Saksham; Smith, Timothy R; Broekman, Marike L

    2017-08-01

    The field of oncology is currently undergoing a paradigm shift. Advances in the understanding of tumor biology and in tumor sequencing technology have contributed to the shift towards precision medicine, the therapeutic framework of targeting the individual oncogenic changes each tumor harbors. The success of precision medicine therapies, such as targeted kinase inhibitors and immunotherapies, in other cancers have motivated studies in brain cancers. The high specificity and cost of these therapies also encourage a shift in clinical trial design away from randomized control trials towards smaller, more exclusive early phase clinical trials. While these new trials advance the clinical application of increasingly precise and individualized therapies, their design brings ethical challenges . We review the pertinent ethical considerations for clinical trials of precision medicine in neuro-oncology and discuss methods to protect patients in this new era of trial design.

  13. Mechanism for accurate, protein-assisted DNA annealing by Deinococcus radiodurans DdrB

    PubMed Central

    Sugiman-Marangos, Seiji N.; Weiss, Yoni M.; Junop, Murray S.

    2016-01-01

    Accurate pairing of DNA strands is essential for repair of DNA double-strand breaks (DSBs). How cells achieve accurate annealing when large regions of single-strand DNA are unpaired has remained unclear despite many efforts focused on understanding proteins, which mediate this process. Here we report the crystal structure of a single-strand annealing protein [DdrB (DNA damage response B)] in complex with a partially annealed DNA intermediate to 2.2 Å. This structure and supporting biochemical data reveal a mechanism for accurate annealing involving DdrB-mediated proofreading of strand complementarity. DdrB promotes high-fidelity annealing by constraining specific bases from unauthorized association and only releases annealed duplex when bound strands are fully complementary. To our knowledge, this mechanism provides the first understanding for how cells achieve accurate, protein-assisted strand annealing under biological conditions that would otherwise favor misannealing. PMID:27044084

  14. Synthetic Gene Expression Circuits for Designing Precision Tools in Oncology

    PubMed Central

    Re, Angela

    2017-01-01

    Precision medicine in oncology needs to enhance its capabilities to match diagnostic and therapeutic technologies to individual patients. Synthetic biology streamlines the design and construction of functionalized devices through standardization and rational engineering of basic biological elements decoupled from their natural context. Remarkable improvements have opened the prospects for the availability of synthetic devices of enhanced mechanism clarity, robustness, sensitivity, as well as scalability and portability, which might bring new capabilities in precision cancer medicine implementations. In this review, we begin by presenting a brief overview of some of the major advances in the engineering of synthetic genetic circuits aimed to the control of gene expression and operating at the transcriptional, post-transcriptional/translational, and post-translational levels. We then focus on engineering synthetic circuits as an enabling methodology for the successful establishment of precision technologies in oncology. We describe significant advancements in our capabilities to tailor synthetic genetic circuits to specific applications in tumor diagnosis, tumor cell- and gene-based therapy, and drug delivery. PMID:28894736

  15. Data Sharing For Precision Medicine: Policy Lessons And Future Directions.

    PubMed

    Blasimme, Alessandro; Fadda, Marta; Schneider, Manuel; Vayena, Effy

    2018-05-01

    Data sharing is a precondition of precision medicine. Numerous organizations have produced abundant guidance on data sharing. Despite such efforts, data are not being shared to a degree that can trigger the expected data-driven revolution in precision medicine. We set out to explore why. Here we report the results of a comprehensive analysis of data-sharing guidelines issued over the past two decades by multiple organizations. We found that the guidelines overlap on a restricted set of policy themes. However, we observed substantial fragmentation in the policy landscape across specific organizations and data types. This may have contributed to the current stalemate in data sharing. To move toward a more efficient data-sharing ecosystem for precision medicine, policy makers should explore innovative ways to cope with central policy themes such as privacy, consent, and data quality; focus guidance on interoperability, attribution, and public engagement; and promote data-sharing policies that can be adapted to multiple data types.

  16. Effective theory for the nonrigid rotor in an electromagnetic field: Toward accurate and precise calculations of E2 transitions in deformed nuclei

    DOE PAGES

    Coello Pérez, Eduardo A.; Papenbrock, Thomas F.

    2015-07-27

    In this paper, we present a model-independent approach to electric quadrupole transitions of deformed nuclei. Based on an effective theory for axially symmetric systems, the leading interactions with electromagnetic fields enter as minimal couplings to gauge potentials, while subleading corrections employ gauge-invariant nonminimal couplings. This approach yields transition operators that are consistent with the Hamiltonian, and the power counting of the effective theory provides us with theoretical uncertainty estimates. We successfully test the effective theory in homonuclear molecules that exhibit a large separation of scales. For ground-state band transitions of rotational nuclei, the effective theory describes data well within theoreticalmore » uncertainties at leading order. To probe the theory at subleading order, data with higher precision would be valuable. For transitional nuclei, next-to-leading-order calculations and the high-precision data are consistent within the theoretical uncertainty estimates. In addition, we study the faint interband transitions within the effective theory and focus on the E2 transitions from the 0 2 + band (the “β band”) to the ground-state band. Here the predictions from the effective theory are consistent with data for several nuclei, thereby proposing a solution to a long-standing challenge.« less

  17. Precision Airdrop (Largage de precision)

    DTIC Science & Technology

    2005-12-01

    NAVIGATION TO A PRECISION AIRDROP OVERVIEW RTO-AG-300-V24 2 - 9 the point from various compass headings. As the tests are conducted, the resultant...rate. This approach avoids including a magnetic compass for the heading reference, which has difficulties due to local changes in the magnetic field...Scientifica della Difesa ROYAUME-UNI Via XX Settembre 123 Dstl Knowledge Services ESPAGNE 00187 Roma Information Centre, Building 247 SDG TECEN / DGAM

  18. Genetic Mutations and Epigenetic Modifications: Driving Cancer and Informing Precision Medicine

    PubMed Central

    Coyle, Krysta Mila; Boudreau, Jeanette E.

    2017-01-01

    Cancer treatment is undergoing a significant revolution from “one-size-fits-all” cytotoxic therapies to tailored approaches that precisely target molecular alterations. Precision strategies for drug development and patient stratification, based on the molecular features of tumors, are the next logical step in a long history of approaches to cancer therapy. In this review, we discuss the history of cancer treatment from generic natural extracts and radical surgical procedures to site-specific and combinatorial treatment regimens, which have incrementally improved patient outcomes. We discuss the related contributions of genetics and epigenetics to cancer progression and the response to targeted therapies and identify challenges and opportunities for the success of precision medicine. The identification of patients who will benefit from targeted therapies is more complex than simply identifying patients whose tumors harbour the targeted aberration, and intratumoral heterogeneity makes it difficult to determine if a precision therapy is successful during treatment. This heterogeneity enables tumors to develop resistance to targeted approaches; therefore, the rational combination of therapeutic agents will limit the threat of acquired resistance to therapeutic success. By incorporating the view of malignant transformation modulated by networks of genetic and epigenetic interactions, molecular strategies will enable precision medicine for effective treatment across cancer subtypes. PMID:28685150

  19. Extracting Time-Accurate Acceleration Vectors From Nontrivial Accelerometer Arrangements.

    PubMed

    Franck, Jennifer A; Blume, Janet; Crisco, Joseph J; Franck, Christian

    2015-09-01

    Sports-related concussions are of significant concern in many impact sports, and their detection relies on accurate measurements of the head kinematics during impact. Among the most prevalent recording technologies are videography, and more recently, the use of single-axis accelerometers mounted in a helmet, such as the HIT system. Successful extraction of the linear and angular impact accelerations depends on an accurate analysis methodology governed by the equations of motion. Current algorithms are able to estimate the magnitude of acceleration and hit location, but make assumptions about the hit orientation and are often limited in the position and/or orientation of the accelerometers. The newly formulated algorithm presented in this manuscript accurately extracts the full linear and rotational acceleration vectors from a broad arrangement of six single-axis accelerometers directly from the governing set of kinematic equations. The new formulation linearizes the nonlinear centripetal acceleration term with a finite-difference approximation and provides a fast and accurate solution for all six components of acceleration over long time periods (>250 ms). The approximation of the nonlinear centripetal acceleration term provides an accurate computation of the rotational velocity as a function of time and allows for reconstruction of a multiple-impact signal. Furthermore, the algorithm determines the impact location and orientation and can distinguish between glancing, high rotational velocity impacts, or direct impacts through the center of mass. Results are shown for ten simulated impact locations on a headform geometry computed with three different accelerometer configurations in varying degrees of signal noise. Since the algorithm does not require simplifications of the actual impacted geometry, the impact vector, or a specific arrangement of accelerometer orientations, it can be easily applied to many impact investigations in which accurate kinematics need

  20. A high-precision sampling scheme to assess persistence and transport characteristics of micropollutants in rivers.

    PubMed

    Schwientek, Marc; Guillet, Gaëlle; Rügner, Hermann; Kuch, Bertram; Grathwohl, Peter

    2016-01-01

    Increasing numbers of organic micropollutants are emitted into rivers via municipal wastewaters. Due to their persistence many pollutants pass wastewater treatment plants without substantial removal. Transport and fate of pollutants in receiving waters and export to downstream ecosystems is not well understood. In particular, a better knowledge of processes governing their environmental behavior is needed. Although a lot of data are available concerning the ubiquitous presence of micropollutants in rivers, accurate data on transport and removal rates are lacking. In this paper, a mass balance approach is presented, which is based on the Lagrangian sampling scheme, but extended to account for precise transport velocities and mixing along river stretches. The calculated mass balances allow accurate quantification of pollutants' reactivity along river segments. This is demonstrated for representative members of important groups of micropollutants, e.g. pharmaceuticals, musk fragrances, flame retardants, and pesticides. A model-aided analysis of the measured data series gives insight into the temporal dynamics of removal processes. The occurrence of different removal mechanisms such as photooxidation, microbial degradation, and volatilization is discussed. The results demonstrate, that removal processes are highly variable in time and space and this has to be considered for future studies. The high precision sampling scheme presented could be a powerful tool for quantifying removal processes under different boundary conditions and in river segments with contrasting properties. Copyright © 2015. Published by Elsevier B.V.

  1. Accurate Energy Consumption Modeling of IEEE 802.15.4e TSCH Using Dual-BandOpenMote Hardware.

    PubMed

    Daneels, Glenn; Municio, Esteban; Van de Velde, Bruno; Ergeerts, Glenn; Weyn, Maarten; Latré, Steven; Famaey, Jeroen

    2018-02-02

    The Time-Slotted Channel Hopping (TSCH) mode of the IEEE 802.15.4e amendment aims to improve reliability and energy efficiency in industrial and other challenging Internet-of-Things (IoT) environments. This paper presents an accurate and up-to-date energy consumption model for devices using this IEEE 802.15.4e TSCH mode. The model identifies all network-related CPU and radio state changes, thus providing a precise representation of the device behavior and an accurate prediction of its energy consumption. Moreover, energy measurements were performed with a dual-band OpenMote device, running the OpenWSN firmware. This allows the model to be used for devices using 2.4 GHz, as well as 868 MHz. Using these measurements, several network simulations were conducted to observe the TSCH energy consumption effects in end-to-end communication for both frequency bands. Experimental verification of the model shows that it accurately models the consumption for all possible packet sizes and that the calculated consumption on average differs less than 3% from the measured consumption. This deviation includes measurement inaccuracies and the variations of the guard time. As such, the proposed model is very suitable for accurate energy consumption modeling of TSCH networks.

  2. Accurate Energy Consumption Modeling of IEEE 802.15.4e TSCH Using Dual-BandOpenMote Hardware

    PubMed Central

    Municio, Esteban; Van de Velde, Bruno; Latré, Steven

    2018-01-01

    The Time-Slotted Channel Hopping (TSCH) mode of the IEEE 802.15.4e amendment aims to improve reliability and energy efficiency in industrial and other challenging Internet-of-Things (IoT) environments. This paper presents an accurate and up-to-date energy consumption model for devices using this IEEE 802.15.4e TSCH mode. The model identifies all network-related CPU and radio state changes, thus providing a precise representation of the device behavior and an accurate prediction of its energy consumption. Moreover, energy measurements were performed with a dual-band OpenMote device, running the OpenWSN firmware. This allows the model to be used for devices using 2.4 GHz, as well as 868 MHz. Using these measurements, several network simulations were conducted to observe the TSCH energy consumption effects in end-to-end communication for both frequency bands. Experimental verification of the model shows that it accurately models the consumption for all possible packet sizes and that the calculated consumption on average differs less than 3% from the measured consumption. This deviation includes measurement inaccuracies and the variations of the guard time. As such, the proposed model is very suitable for accurate energy consumption modeling of TSCH networks. PMID:29393900

  3. Superpixel-based graph cuts for accurate stereo matching

    NASA Astrophysics Data System (ADS)

    Feng, Liting; Qin, Kaihuai

    2017-06-01

    Estimating the surface normal vector and disparity of a pixel simultaneously, also known as three-dimensional label method, has been widely used in recent continuous stereo matching problem to achieve sub-pixel accuracy. However, due to the infinite label space, it’s extremely hard to assign each pixel an appropriate label. In this paper, we present an accurate and efficient algorithm, integrating patchmatch with graph cuts, to approach this critical computational problem. Besides, to get robust and precise matching cost, we use a convolutional neural network to learn a similarity measure on small image patches. Compared with other MRF related methods, our method has several advantages: its sub-modular property ensures a sub-problem optimality which is easy to perform in parallel; graph cuts can simultaneously update multiple pixels, avoiding local minima caused by sequential optimizers like belief propagation; it uses segmentation results for better local expansion move; local propagation and randomization can easily generate the initial solution without using external methods. Middlebury experiments show that our method can get higher accuracy than other MRF-based algorithms.

  4. Precise calibration of few-cycle laser pulses with atomic hydrogen

    NASA Astrophysics Data System (ADS)

    Wallace, W. C.; Kielpinski, D.; Litvinyuk, I. V.; Sang, R. T.

    2017-12-01

    Interaction of atoms and molecules with strong electric fields is a fundamental process in many fields of research, particularly in the emerging field of attosecond science. Therefore, understanding the physics underpinning those interactions is of significant interest to the scientific community. One crucial step in this understanding is accurate knowledge of the few-cycle laser field driving the process. Atomic hydrogen (H), the simplest of all atomic species, plays a key role in benchmarking strong-field processes. Its wide-spread use as a testbed for theoretical calculations allows the comparison of approximate theoretical models against nearly-perfect numerical solutions of the three-dimensional time-dependent Schrödinger equation. Until recently, relatively little experimental data in atomic H was available for comparison to these models, and was due mostly due to the difficulty in the construction and use of atomic H sources. Here, we review our most recent experimental results from atomic H interaction with few-cycle laser pulses and how they have been used to calibrate important laser pulse parameters such as peak intensity and the carrier-envelope phase (CEP). Quantitative agreement between experimental data and theoretical predictions for atomic H has been obtained at the 10% uncertainty level, allowing for accurate laser calibration intensity at the 1% level. Using this calibration in atomic H, both accurate CEP data and an intensity calibration standard have been obtained Ar, Kr, and Xe; such gases are in common use for strong-field experiments. This calibration standard can be used by any laboratory using few-cycle pulses in the 1014 W cm-2 intensity regime centered at 800 nm wavelength to accurately calibrate their peak laser intensity to within few-percent precision.

  5. Precise locating approach of the beacon based on gray gradient segmentation interpolation in satellite optical communications.

    PubMed

    Wang, Qiang; Liu, Yuefei; Chen, Yiqiang; Ma, Jing; Tan, Liying; Yu, Siyuan

    2017-03-01

    Accurate location computation for a beacon is an important factor of the reliability of satellite optical communications. However, location precision is generally limited by the resolution of CCD. How to improve the location precision of a beacon is an important and urgent issue. In this paper, we present two precise centroid computation methods for locating a beacon in satellite optical communications. First, in terms of its characteristics, the beacon is divided into several parts according to the gray gradients. Afterward, different numbers of interpolation points and different interpolation methods are applied in the interpolation area; we calculate the centroid position after interpolation and choose the best strategy according to the algorithm. The method is called a "gradient segmentation interpolation approach," or simply, a GSI (gradient segmentation interpolation) algorithm. To take full advantage of the pixels of the beacon's central portion, we also present an improved segmentation square weighting (SSW) algorithm, whose effectiveness is verified by the simulation experiment. Finally, an experiment is established to verify GSI and SSW algorithms. The results indicate that GSI and SSW algorithms can improve locating accuracy over that calculated by a traditional gray centroid method. These approaches help to greatly improve the location precision for a beacon in satellite optical communications.

  6. Precision Cosmology

    NASA Astrophysics Data System (ADS)

    Jones, Bernard J. T.

    2017-04-01

    Preface; Notation and conventions; Part I. 100 Years of Cosmology: 1. Emerging cosmology; 2. The cosmic expansion; 3. The cosmic microwave background; 4. Recent cosmology; Part II. Newtonian Cosmology: 5. Newtonian cosmology; 6. Dark energy cosmological models; 7. The early universe; 8. The inhomogeneous universe; 9. The inflationary universe; Part III. Relativistic Cosmology: 10. Minkowski space; 11. The energy momentum tensor; 12. General relativity; 13. Space-time geometry and calculus; 14. The Einstein field equations; 15. Solutions of the Einstein equations; 16. The Robertson-Walker solution; 17. Congruences, curvature and Raychaudhuri; 18. Observing and measuring the universe; Part IV. The Physics of Matter and Radiation: 19. Physics of the CMB radiation; 20. Recombination of the primeval plasma; 21. CMB polarisation; 22. CMB anisotropy; Part V. Precision Tools for Precision Cosmology: 23. Likelihood; 24. Frequentist hypothesis testing; 25. Statistical inference: Bayesian; 26. CMB data processing; 27. Parametrising the universe; 28. Precision cosmology; 29. Epilogue; Appendix A. SI, CGS and Planck units; Appendix B. Magnitudes and distances; Appendix C. Representing vectors and tensors; Appendix D. The electromagnetic field; Appendix E. Statistical distributions; Appendix F. Functions on a sphere; Appendix G. Acknowledgements; References; Index.

  7. Integration of phytochemicals and phytotherapy into cancer precision medicine.

    PubMed

    Efferth, Thomas; Saeed, Mohamed E M; Mirghani, Elhaj; Alim, Awadh; Yassin, Zahir; Saeed, Elfatih; Khalid, Hassan E; Daak, Salah

    2017-07-25

    Concepts of individualized therapy in the 1970s and 1980s attempted to develop predictive in vitro tests for individual drug responsiveness without reaching clinical routine. Precision medicine attempts to device novel individual cancer therapy strategies. Using bioinformatics, relevant knowledge is extracted from huge data amounts. However, tumor heterogeneity challenges chemotherapy due to genetically and phenotypically different cell subpopulations, which may lead to refractory tumors. Natural products always served as vital resources for cancer therapy (e.g., Vinca alkaloids, camptothecin, paclitaxel, etc.) and are also sources for novel drugs. Targeted drugs developed to specifically address tumor-related proteins represent the basis of precision medicine. Natural products from plants represent excellent resource for targeted therapies. Phytochemicals and herbal mixtures act multi-specifically, i.e. they attack multiple targets at the same time. Network pharmacology facilitates the identification of the complexity of pharmacogenomic networks and new signaling networks that are distorted in tumors. In the present review, we give a conceptual overview, how the problem of drug resistance may be approached by integrating phytochemicals and phytotherapy into academic western medicine. Modern technology platforms (e.g. "-omics" technologies, DNA/RNA sequencing, and network pharmacology) can be applied for diverse treatment modalities such as cytotoxic and targeted chemotherapy as well as phytochemicals and phytotherapy. Thereby, these technologies represent an integrative momentum to merge the best of two worlds: clinical oncology and traditional medicine. In conclusion, the integration of phytochemicals and phytotherapy into cancer precision medicine represents a valuable asset to chemically synthesized chemicals and therapeutic antibodies.

  8. Design of a Soil Cutting Resistance Sensor for Application in Site-Specific Tillage

    PubMed Central

    Agüera, Juan; Carballido, Jacob; Gil, Jesús; Gliever, Chris J.; Perez-Ruiz, Manuel

    2013-01-01

    One objective of precision agriculture is to provide accurate information about soil and crop properties to optimize the management of agricultural inputs to meet site-specific needs. This paper describes the development of a sensor equipped with RTK-GPS technology that continuously and efficiently measures soil cutting resistance at various depths while traversing the field. Laboratory and preliminary field tests verified the accuracy of this prototype soil strength sensor. The data obtained using a hand-operated soil cone penetrometer was used to evaluate this field soil compaction depth profile sensor. To date, this sensor has only been tested in one field under one gravimetric water content condition. This field test revealed that the relationships between the soil strength profile sensor (SSPS) cutting force and soil cone index values are assumed to be quadratic for the various depths considered: 0–10, 10–20 and 20–30 cm (r2 = 0.58, 0.45 and 0.54, respectively). Soil resistance contour maps illustrated its practical value. The developed sensor provides accurate, timely and affordable information on soil properties to optimize resources and improve agricultural economy. PMID:23666127

  9. Precise and absolute measurements of complex third-order optical susceptibility

    NASA Astrophysics Data System (ADS)

    Santran, Stephane; Canioni, Lionel; Cardinal, Thierry; Fargin, Evelyne; Le Flem, Gilles; Rouyer, Claude; Sarger, Laurent

    2000-11-01

    We present precise and absolute measurements of full complex third order optical susceptibility on different fused silica and original glasses composed of tellurium, titanium, niobium erbium. These materials are designed to be the key point for applications ranging form high power laser systems to optoelectronics, their nonlinear index of refraction is a major property and thus must be accurately known. Due to the accuracy and sensitivity of our technique, we have been able to find a large dispersion (more than 30%) of the non linear index of fused silica glasses as a function of their processing mode. On the other hand, measurements on tellurium glasses have shown very strong nonlinearities (40 times higher than fused silica), to be linked to the configurations of their cations and anions. Although the titanium and niobium glasses are less nonlinear, they can be promising matrices for addition of luminescent entities like erbium leading to very interesting laser amplification materials. The experimental set-up is a collinear pump-probe (orthogonally polarized) experiment using transient absorption technique. It is built with around a 100 femtosecond laser oscillator. A fast oscillating delay between the pump and the probe allows us to measure the electronic nonlinearity in quasi real-time. This experiment has the following specifications: an absolute measurement accuracy below 10% mainly due to the laser parameters characterization, a relative measurement accuracy of 1% and a resolution less than 5.10-24m2/V2(50 times less than fused silica).

  10. Precision medicine and precision therapeutics: hedgehog signaling pathway, basal cell carcinoma and beyond.

    PubMed

    Mohan, Shalini V; Chang, Anne Lynn S

    2014-06-01

    Precision medicine and precision therapeutics is currently in its infancy with tremendous potential to improve patient care by better identifying individuals at risk for skin cancer and predict tumor responses to treatment. This review focuses on the Hedgehog signaling pathway, its critical role in the pathogenesis of basal cell carcinoma, and the emergence of targeted treatments for advanced basal cell carcinoma. Opportunities to utilize precision medicine are outlined, such as molecular profiling to predict basal cell carcinoma response to targeted therapy and to inform therapeutic decisions.

  11. Estimating sensitivity and specificity for technology assessment based on observer studies.

    PubMed

    Nishikawa, Robert M; Pesce, Lorenzo L

    2013-07-01

    The goal of this study was to determine the accuracy and precision of using scores from a receiver operating characteristic rating scale to estimate sensitivity and specificity. We used data collected in a previous study that measured the improvements in radiologists' ability to classify mammographic microcalcification clusters as benign or malignant with and without the use of a computer-aided diagnosis scheme. Sensitivity and specificity were estimated from the rating data from a question that directly asked the radiologists their biopsy recommendations, which was used as the "truth," because it is the actual recall decision, thus it is their subjective truth. By thresholding the rating data, sensitivity and specificity were estimated for different threshold values. Because of interreader and intrareader variability, estimated sensitivity and specificity values for individual readers could be as much as 100% in error when using rating data compared to using the biopsy recommendation data. When pooled together, the estimates using thresholding the rating data were in good agreement with sensitivity and specificity estimated from the recommendation data. However, the statistical power of the rating data estimates was lower. By simply asking the observer his or her explicit recommendation (eg, biopsy or no biopsy), sensitivity and specificity can be measured directly, giving a more accurate description of empirical variability and the power of the study can be maximized. Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.

  12. Precise identification of Dirac-like point through a finite photonic crystal square matrix

    PubMed Central

    Dong, Guoyan; Zhou, Ji; Yang, Xiulun; Meng, Xiangfeng

    2016-01-01

    The phenomena of the minimum transmittance spectrum or the maximum reflection spectrum located around the Dirac frequency have been observed to demonstrate the 1/L scaling law near the Dirac-like point through the finite ribbon structure. However, so far there is no effective way to identify the Dirac-like point accurately. In this work we provide an effective measurement method to identify the Dirac-like point accurately through a finite photonic crystal square matrix. Based on the Dirac-like dispersion achieved by the accidental degeneracy at the centre of the Brillouin zone of dielectric photonic crystal, both the simulated and experimental results demonstrate that the transmittance spectra through a finite photonic crystal square matrix not only provide the clear evidence for the existence of Dirac-like point but also can be used to identify the precise location of Dirac-like point by the characteristics of sharp cusps embedded in the extremum spectra surrounding the conical singularity. PMID:27857145

  13. Accurate joint space quantification in knee osteoarthritis: a digital x-ray tomosynthesis phantom study

    NASA Astrophysics Data System (ADS)

    Sewell, Tanzania S.; Piacsek, Kelly L.; Heckel, Beth A.; Sabol, John M.

    2011-03-01

    The current imaging standard for diagnosis and monitoring of knee osteoarthritis (OA) is projection radiography. However radiographs may be insensitive to markers of early disease such as osteophytes and joint space narrowing (JSN). Relative to standard radiography, digital X-ray tomosynthesis (DTS) may provide improved visualization of the markers of knee OA without the interference of superimposed anatomy. DTS utilizes a series of low-dose projection images over an arc of +/-20 degrees to reconstruct tomographic images parallel to the detector. We propose that DTS can increase accuracy and precision in JSN quantification. The geometric accuracy of DTS was characterized by quantifying joint space width (JSW) as a function of knee flexion and position using physical and anthropomorphic phantoms. Using a commercially available digital X-ray system, projection and DTS images were acquired for a Lucite rod phantom with known gaps at various source-object-distances, and angles of flexion. Gap width, representative of JSW, was measured using a validated algorithm. Over an object-to-detector-distance range of 5-21cm, a 3.0mm gap width was reproducibly measured in the DTS images, independent of magnification. A simulated 0.50mm (+/-0.13) JSN was quantified accurately (95% CI 0.44-0.56mm) in the DTS images. Angling the rods to represent knee flexion, the minimum gap could be precisely determined from the DTS images and was independent of flexion angle. JSN quantification using DTS was insensitive to distance from patient barrier and flexion angle. Potential exists for the optimization of DTS for accurate radiographic quantification of knee OA independent of patient positioning.

  14. Accuracy, precision, and economic efficiency for three methods of thrips (Thysanoptera: Thripidae) population density assessment.

    PubMed

    Sutherland, Andrew M; Parrella, Michael P

    2011-08-01

    Western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), is a major horticultural pest and an important vector of plant viruses in many parts of the world. Methods for assessing thrips population density for pest management decision support are often inaccurate or imprecise due to thrips' positive thigmotaxis, small size, and naturally aggregated populations. Two established methods, flower tapping and an alcohol wash, were compared with a novel method, plant desiccation coupled with passive trapping, using accuracy, precision and economic efficiency as comparative variables. Observed accuracy was statistically similar and low (37.8-53.6%) for all three methods. Flower tapping was the least expensive method, in terms of person-hours, whereas the alcohol wash method was the most expensive. Precision, expressed by relative variation, depended on location within the greenhouse, location on greenhouse benches, and the sampling week, but it was generally highest for the flower tapping and desiccation methods. Economic efficiency, expressed by relative net precision, was highest for the flower tapping method and lowest for the alcohol wash method. Advantages and disadvantages are discussed for all three methods used. If relative density assessment methods such as these can all be assumed to accurately estimate a constant proportion of absolute density, then high precision becomes the methodological goal in terms of measuring insect population density, decision making for pest management, and pesticide efficacy assessments.

  15. Self-position estimation using terrain shadows for precise planetary landing

    NASA Astrophysics Data System (ADS)

    Kuga, Tomoki; Kojima, Hirohisa

    2018-07-01

    In recent years, the investigation of moons and planets has attracted increasing attention in several countries. Furthermore, recently developed landing systems are now expected to reach more scientifically interesting areas close to hazardous terrain, requiring precise landing capabilities within a 100 m range of the target point. To achieve this, terrain-relative navigation (capable of estimating the position of a lander relative to the target point on the ground surface is actively being studied as an effective method for achieving highly accurate landings. This paper proposes a self-position estimation method using shadows on the terrain based on edge extraction from image processing algorithms. The effectiveness of the proposed method is validated through numerical simulations using images generated from a digital elevation model of simulated terrains.

  16. Spatially resolved photodiode response for simulating precise interferometers.

    PubMed

    Fernández Barranco, Germán; Tröbs, Michael; Müller, Vitali; Gerberding, Oliver; Seifert, Frank; Heinzel, Gerhard

    2016-08-20

    Quadrant photodiodes (QPDs) are used in laser interferometry systems to simultaneously detect longitudinal displacement of test masses and angular misalignment between the two interfering beams. The latter is achieved by means of the differential wavefront sensing (DWS) technique, which provides ultra-high precision for measuring angular displacements. We have developed a setup to obtain the spatially resolved response of QPDs that, together with an extension of the simulation software IfoCAD, allows us to use the measured response in simulations and accurately predict the desired longitudinal and DWS phase observables. Three different commercial off-the-shelf QPD candidates for space-based interferometry were characterized. The measured response of one QPD was used in optical simulations. Nonuniformities in the response of the device and crosstalk between segments do not introduce significant variations in the longitudinal and DWS measurands with respect to the standard case when a uniform QPD without crosstalk is used.

  17. Pragmatic precision oncology: the secondary uses of clinical tumor molecular profiling.

    PubMed

    Rioth, Matthew J; Thota, Ramya; Staggs, David B; Johnson, Douglas B; Warner, Jeremy L

    2016-07-01

    Precision oncology increasingly utilizes molecular profiling of tumors to determine treatment decisions with targeted therapeutics. The molecular profiling data is valuable in the treatment of individual patients as well as for multiple secondary uses. To automatically parse, categorize, and aggregate clinical molecular profile data generated during cancer care as well as use this data to address multiple secondary use cases. A system to parse, categorize and aggregate molecular profile data was created. A naÿve Bayesian classifier categorized results according to clinical groups. The accuracy of these systems were validated against a published expertly-curated subset of molecular profiling data. Following one year of operation, 819 samples have been accurately parsed and categorized to generate a data repository of 10,620 genetic variants. The database has been used for operational, clinical trial, and discovery science research. A real-time database of molecular profiling data is a pragmatic solution to several knowledge management problems in the practice and science of precision oncology. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Learning-based computing techniques in geoid modeling for precise height transformation

    NASA Astrophysics Data System (ADS)

    Erol, B.; Erol, S.

    2013-03-01

    Precise determination of local geoid is of particular importance for establishing height control in geodetic GNSS applications, since the classical leveling technique is too laborious. A geoid model can be accurately obtained employing properly distributed benchmarks having GNSS and leveling observations using an appropriate computing algorithm. Besides the classical multivariable polynomial regression equations (MPRE), this study attempts an evaluation of learning based computing algorithms: artificial neural networks (ANNs), adaptive network-based fuzzy inference system (ANFIS) and especially the wavelet neural networks (WNNs) approach in geoid surface approximation. These algorithms were developed parallel to advances in computer technologies and recently have been used for solving complex nonlinear problems of many applications. However, they are rather new in dealing with precise modeling problem of the Earth gravity field. In the scope of the study, these methods were applied to Istanbul GPS Triangulation Network data. The performances of the methods were assessed considering the validation results of the geoid models at the observation points. In conclusion the ANFIS and WNN revealed higher prediction accuracies compared to ANN and MPRE methods. Beside the prediction capabilities, these methods were also compared and discussed from the practical point of view in conclusions.

  19. Robust adhesive precision bonding in automated assembly cells

    NASA Astrophysics Data System (ADS)

    Müller, Tobias; Haag, Sebastian; Bastuck, Thomas; Gisler, Thomas; Moser, Hansruedi; Uusimaa, Petteri; Axt, Christoph; Brecher, Christian

    2014-03-01

    Diode lasers are gaining importance, making their way to higher output powers along with improved BPP. The assembly of micro-optics for diode laser systems goes along with the highest requirements regarding assembly precision. Assembly costs for micro-optics are driven by the requirements regarding alignment in a submicron and the corresponding challenges induced by adhesive bonding. For micro-optic assembly tasks a major challenge in adhesive bonding at highest precision level is the fact, that the bonding process is irreversible. Accordingly, the first bonding attempt needs to be successful. Today's UV-curing adhesives inherit shrinkage effects crucial for submicron tolerances of e.g. FACs. The impact of the shrinkage effects can be tackled by a suitable bonding area design, such as minimal adhesive gaps and an adapted shrinkage offset value for the specific assembly parameters. Compensating shrinkage effects is difficult, as the shrinkage of UV-curing adhesives is not constant between two different lots and varies even over the storage period even under ideal circumstances as first test results indicate. An up-to-date characterization of the adhesive appears necessary for maximum precision in optics assembly to reach highest output yields, minimal tolerances and ideal beamshaping results. Therefore, a measurement setup to precisely determine the up-to-date level of shrinkage has been setup. The goal is to provide necessary information on current shrinkage to the operator or assembly cell to adjust the compensation offset on a daily basis. Impacts of this information are expected to be an improved beam shaping result and a first-time-right production.

  20. Patient similarity for precision medicine: a systematic review.

    PubMed

    Parimbelli, E; Marini, S; Sacchi, L; Bellazzi, R

    2018-06-01

    Evidence-based medicine is the most prevalent paradigm adopted by physicians. Clinical practice guidelines typically define a set of recommendations together with eligibility criteria that restrict their applicability to a specific group of patients. The ever-growing size and availability of health-related data is currently challenging the broad definitions of guideline-defined patient groups. Precision medicine leverages on genetic, phenotypic, or psychosocial characteristics to provide precise identification of patient subsets for treatment targeting. Defining a patient similarity measure is thus an essential step to allow stratification of patients into clinically-meaningful subgroups. The present review investigates the use of patient similarity as a tool to enable precision medicine. 279 articles were analyzed along four dimensions: data types considered, clinical domains of application, data analysis methods, and translational stage of findings. Cancer-related research employing molecular profiling and standard data analysis techniques such as clustering constitute the majority of the retrieved studies. Chronic and psychiatric diseases follow as the second most represented clinical domains. Interestingly, almost one quarter of the studies analyzed presented a novel methodology, with the most advanced employing data integration strategies and being portable to different clinical domains. Integration of such techniques into decision support systems constitutes and interesting trend for future research. Copyright © 2018. Published by Elsevier Inc.

  1. Precision production: enabling deterministic throughput for precision aspheres with MRF

    NASA Astrophysics Data System (ADS)

    Maloney, Chris; Entezarian, Navid; Dumas, Paul

    2017-10-01

    Aspherical lenses offer advantages over spherical optics by improving image quality or reducing the number of elements necessary in an optical system. Aspheres are no longer being used exclusively by high-end optical systems but are now replacing spherical optics in many applications. The need for a method of production-manufacturing of precision aspheres has emerged and is part of the reason that the optics industry is shifting away from artisan-based techniques towards more deterministic methods. Not only does Magnetorheological Finishing (MRF) empower deterministic figure correction for the most demanding aspheres but it also enables deterministic and efficient throughput for series production of aspheres. The Q-flex MRF platform is designed to support batch production in a simple and user friendly manner. Thorlabs routinely utilizes the advancements of this platform and has provided results from using MRF to finish a batch of aspheres as a case study. We have developed an analysis notebook to evaluate necessary specifications for implementing quality control metrics. MRF brings confidence to optical manufacturing by ensuring high throughput for batch processing of aspheres.

  2. Accurate object tracking system by integrating texture and depth cues

    NASA Astrophysics Data System (ADS)

    Chen, Ju-Chin; Lin, Yu-Hang

    2016-03-01

    A robust object tracking system that is invariant to object appearance variations and background clutter is proposed. Multiple instance learning with a boosting algorithm is applied to select discriminant texture information between the object and background data. Additionally, depth information, which is important to distinguish the object from a complicated background, is integrated. We propose two depth-based models that can compensate texture information to cope with both appearance variants and background clutter. Moreover, in order to reduce the risk of drifting problem increased for the textureless depth templates, an update mechanism is proposed to select more precise tracking results to avoid incorrect model updates. In the experiments, the robustness of the proposed system is evaluated and quantitative results are provided for performance analysis. Experimental results show that the proposed system can provide the best success rate and has more accurate tracking results than other well-known algorithms.

  3. Accurate oscillator strengths for interstellar ultraviolet lines of Cl I

    NASA Technical Reports Server (NTRS)

    Schectman, R. M.; Federman, S. R.; Beideck, D. J.; Ellis, D. J.

    1993-01-01

    Analyses on the abundance of interstellar chlorine rely on accurate oscillator strengths for ultraviolet transitions. Beam-foil spectroscopy was used to obtain f-values for the astrophysically important lines of Cl I at 1088, 1097, and 1347 A. In addition, the line at 1363 A was studied. Our f-values for 1088, 1097 A represent the first laboratory measurements for these lines; the values are f(1088)=0.081 +/- 0.007 (1 sigma) and f(1097) = 0.0088 +/- 0.0013 (1 sigma). These results resolve the issue regarding the relative strengths for 1088, 1097 A in favor of those suggested by astronomical measurements. For the other lines, our results of f(1347) = 0.153 +/- 0.011 (1 sigma) and f(1363) = 0.055 +/- 0.004 (1 sigma) are the most precisely measured values available. The f-values are somewhat greater than previous experimental and theoretical determinations.

  4. Research on a high-precision calibration method for tunable lasers

    NASA Astrophysics Data System (ADS)

    Xiang, Na; Li, Zhengying; Gui, Xin; Wang, Fan; Hou, Yarong; Wang, Honghai

    2018-03-01

    Tunable lasers are widely used in the field of optical fiber sensing, but nonlinear tuning exists even for zero external disturbance and limits the accuracy of the demodulation. In this paper, a high-precision calibration method for tunable lasers is proposed. A comb filter is introduced and the real-time output wavelength and scanning rate of the laser are calibrated by linear fitting several time-frequency reference points obtained from it, while the beat signal generated by the auxiliary interferometer is interpolated and frequency multiplied to find more accurate zero crossing points, with these points being used as wavelength counters to resample the comb signal to correct the nonlinear effect, which ensures that the time-frequency reference points of the comb filter are linear. A stability experiment and a strain sensing experiment verify the calibration precision of this method. The experimental result shows that the stability and wavelength resolution of the FBG demodulation can reach 0.088 pm and 0.030 pm, respectively, using a tunable laser calibrated by the proposed method. We have also compared the demodulation accuracy in the presence or absence of the comb filter, with the result showing that the introduction of the comb filter results to a 15-fold wavelength resolution enhancement.

  5. Detection of nucleotide-specific CRISPR/Cas9 modified alleles using multiplex ligation detection

    PubMed Central

    KC, R.; Srivastava, A.; Wilkowski, J. M.; Richter, C. E.; Shavit, J. A.; Burke, D. T.; Bielas, S. L.

    2016-01-01

    CRISPR/Cas9 genome-editing has emerged as a powerful tool to create mutant alleles in model organisms. However, the precision with which these mutations are created has introduced a new set of complications for genotyping and colony management. Traditional gene-targeting approaches in many experimental organisms incorporated exogenous DNA and/or allele specific sequence that allow for genotyping strategies based on binary readout of PCR product amplification and size selection. In contrast, alleles created by non-homologous end-joining (NHEJ) repair of double-stranded DNA breaks generated by Cas9 are much less amenable to such strategies. Here we describe a novel genotyping strategy that is cost effective, sequence specific and allows for accurate and efficient multiplexing of small insertion-deletions and single-nucleotide variants characteristic of CRISPR/Cas9 edited alleles. We show that ligation detection reaction (LDR) can be used to generate products that are sequence specific and uniquely detected by product size and/or fluorescent tags. The method works independently of the model organism and will be useful for colony management as mutant alleles differing by a few nucleotides become more prevalent in experimental animal colonies. PMID:27557703

  6. Theoretical and experimental research on machine tool servo system for ultra-precision position compensation on CNC lathe

    NASA Astrophysics Data System (ADS)

    Ma, Zhichao; Hu, Leilei; Zhao, Hongwei; Wu, Boda; Peng, Zhenxing; Zhou, Xiaoqin; Zhang, Hongguo; Zhu, Shuai; Xing, Lifeng; Hu, Huang

    2010-08-01

    The theories and techniques for improving machining accuracy via position control of diamond tool's tip and raising resolution of cutting depth on precise CNC lathes have been extremely focused on. A new piezo-driven ultra-precision machine tool servo system is designed and tested to improve manufacturing accuracy of workpiece. The mathematical model of machine tool servo system is established and the finite element analysis is carried out on parallel plate flexure hinges. The output position of diamond tool's tip driven by the machine tool servo system is tested via a contact capacitive displacement sensor. Proportional, integral, derivative (PID) feedback is also implemented to accommodate and compensate dynamical change owing cutting forces as well as the inherent non-linearity factors of the piezoelectric stack during cutting process. By closed loop feedback controlling strategy, the tracking error is limited to 0.8 μm. Experimental results have shown the proposed machine tool servo system could provide a tool positioning resolution of 12 nm, which is much accurate than the inherent CNC resolution magnitude. The stepped shaft of aluminum specimen with a step increment of cutting depth of 1 μm is tested, and the obtained contour illustrates the displacement command output from controller is accurately and real-time reflected on the machined part.

  7. Web mining for topics defined by complex and precise predicates

    NASA Astrophysics Data System (ADS)

    Lee, Ching-Cheng; Sampathkumar, Sushma

    2004-04-01

    The enormous growth of the World Wide Web has made it important to perform resource discovery efficiently for any given topic. Several new techniques have been proposed in the recent years for this kind of topic specific web-mining, and among them a key new technique called focused crawling which is able to crawl topic-specific portions of the web without having to explore all pages. Most existing research on focused crawling considers a simple topic definition that typically consists of one or more keywords connected by an OR operator. However this kind of simple topic definition may result in too many irrelevant pages in which the same keyword appears in a wrong context. In this research we explore new strategies for crawling topic specific portions of the web using complex and precise predicates. A complex predicate will allow the user to precisely specify a topic using Boolean operators such as "AND", "OR" and "NOT". Our work will concentrate on defining a format to specify this kind of a complex topic definition and secondly on devising a crawl strategy to crawl the topic specific portions of the web defined by the complex predicate, efficiently and with minimal overhead. Our new crawl strategy will improve the performance of topic-specific web crawling by reducing the number of irrelevant pages crawled. In order to demonstrate the effectiveness of the above approach, we have built a complete focused crawler called "Eureka" with complex predicate support, and a search engine that indexes and supports end-user searches on the crawled pages.

  8. Intraocular lens power estimation by accurate ray tracing for eyes underwent previous refractive surgeries

    NASA Astrophysics Data System (ADS)

    Yang, Que; Wang, Shanshan; Wang, Kai; Zhang, Chunyu; Zhang, Lu; Meng, Qingyu; Zhu, Qiudong

    2015-08-01

    For normal eyes without history of any ocular surgery, traditional equations for calculating intraocular lens (IOL) power, such as SRK-T, Holladay, Higis, SRK-II, et al., all were relativley accurate. However, for eyes underwent refractive surgeries, such as LASIK, or eyes diagnosed as keratoconus, these equations may cause significant postoperative refractive error, which may cause poor satisfaction after cataract surgery. Although some methods have been carried out to solve this problem, such as Hagis-L equation[1], or using preoperative data (data before LASIK) to estimate K value[2], no precise equations were available for these eyes. Here, we introduced a novel intraocular lens power estimation method by accurate ray tracing with optical design software ZEMAX. Instead of using traditional regression formula, we adopted the exact measured corneal elevation distribution, central corneal thickness, anterior chamber depth, axial length, and estimated effective lens plane as the input parameters. The calculation of intraocular lens power for a patient with keratoconus and another LASIK postoperative patient met very well with their visual capacity after cataract surgery.

  9. Sampling designs matching species biology produce accurate and affordable abundance indices

    PubMed Central

    Farley, Sean; Russell, Gareth J.; Butler, Matthew J.; Selinger, Jeff

    2013-01-01

    Wildlife biologists often use grid-based designs to sample animals and generate abundance estimates. Although sampling in grids is theoretically sound, in application, the method can be logistically difficult and expensive when sampling elusive species inhabiting extensive areas. These factors make it challenging to sample animals and meet the statistical assumption of all individuals having an equal probability of capture. Violating this assumption biases results. Does an alternative exist? Perhaps by sampling only where resources attract animals (i.e., targeted sampling), it would provide accurate abundance estimates more efficiently and affordably. However, biases from this approach would also arise if individuals have an unequal probability of capture, especially if some failed to visit the sampling area. Since most biological programs are resource limited, and acquiring abundance data drives many conservation and management applications, it becomes imperative to identify economical and informative sampling designs. Therefore, we evaluated abundance estimates generated from grid and targeted sampling designs using simulations based on geographic positioning system (GPS) data from 42 Alaskan brown bears (Ursus arctos). Migratory salmon drew brown bears from the wider landscape, concentrating them at anadromous streams. This provided a scenario for testing the targeted approach. Grid and targeted sampling varied by trap amount, location (traps placed randomly, systematically or by expert opinion), and traps stationary or moved between capture sessions. We began by identifying when to sample, and if bears had equal probability of capture. We compared abundance estimates against seven criteria: bias, precision, accuracy, effort, plus encounter rates, and probabilities of capture and recapture. One grid (49 km2 cells) and one targeted configuration provided the most accurate results. Both placed traps by expert opinion and moved traps between capture sessions, which

  10. Improved treatment of global positioning system force parameters in precise orbit determination applications

    NASA Technical Reports Server (NTRS)

    Vigue, Y.; Lichten, S. M.; Muellerschoen, R. J.; Blewitt, G.; Heflin, M. B.

    1993-01-01

    Data collected from a worldwide 1992 experiment were processed at JPL to determine precise orbits for the satellites of the Global Positioning System (GPS). A filtering technique was tested to improve modeling of solar-radiation pressure force parameters for GPS satellites. The new approach improves orbit quality for eclipsing satellites by a factor of two, with typical results in the 25- to 50-cm range. The resultant GPS-based estimates for geocentric coordinates of the tracking sites, which include the three DSN sites, are accurate to 2 to 8 cm, roughly equivalent to 3 to 10 nrad of angular measure.

  11. A case study of precision farming for nutrient management of corn

    NASA Astrophysics Data System (ADS)

    Blanco, Alfonso; Hunt, Ray; Gomez, Richard B.; Roper, William E.

    2003-08-01

    Precision farming relies on the cost effectiveness of collecting and interpreting data, which describes the variations of agricultural conditions such as crop stresses, nutrient deficiencies, water stresses, or pest infestation. Hyperspectral remote sensing from satellites and airborne sensors can be a way to obtain data needed to develop site-specific farming management strategies. The primary objective of the hyperspectral applications in precision farming is to provide farmers with a technology, which can detect specific crop conditions that can be used to program variable-rate applications. Applications of water, pesticides, and fertilizer can be tailored to the needs of the agricultural crops, based on the conditions reflected on the imagery. This paper presents an experimental study performed in Beltsville, Maryland for assessing the plant density and nutrient uptake of corn using a simple photographic method from a model airplane versus obtaining hyperspectral imagery from an airborne sensor. The hyperspectral sensor utilized in this study was the AISA sensor. These remote sensors can measure the temperature of plants; or to be more specific, they can measure how much energy plants emit at the visible and near-infrared wavelengths of the spectrum, such as water and vegetation.

  12. Precision pharmacology for Alzheimer's disease.

    PubMed

    Hampel, Harald; Vergallo, Andrea; Aguilar, Lisi Flores; Benda, Norbert; Broich, Karl; Cuello, A Claudio; Cummings, Jeffrey; Dubois, Bruno; Federoff, Howard J; Fiandaca, Massimo; Genthon, Remy; Haberkamp, Marion; Karran, Eric; Mapstone, Mark; Perry, George; Schneider, Lon S; Welikovitch, Lindsay A; Woodcock, Janet; Baldacci, Filippo; Lista, Simone

    2018-04-01

    disease-modifying pathway-based targeted therapies. PP is based on an exploratory and integrative strategy to complex diseases such as brain proteinopathies including AD, aimed at identifying simultaneous aberrant molecular pathways and predicting their temporal impact on the systems levels. The depiction of pathway-based molecular signatures of complex diseases contributes to the accurate and mechanistic stratification of distinct subcohorts of individuals at the earliest compensatory stage when treatment intervention may reverse, stop, or delay the disease. In addition, individualized drug selection may optimize treatment safety by decreasing risk and amplitude of side effects and adverse reactions. From a methodological point of view, comprehensive "omics"-based biomarkers will guide the exploration of spatio-temporal systems-wide morpho-functional shifts along the continuum of AD pathophysiology, from adaptation to irreversible failure. The Alzheimer Precision Medicine Initiative (APMI) and the APMI cohort program (APMI-CP) have commenced to facilitate a paradigm shift towards effective drug discovery and development in AD. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Real-time, autonomous precise satellite orbit determination using the global positioning system

    NASA Astrophysics Data System (ADS)

    Goldstein, David Ben

    2000-10-01

    The desire for autonomously generated, rapidly available, and highly accurate satellite ephemeris is growing with the proliferation of constellations of satellites and the cost and overhead of ground tracking resources. Autonomous Orbit Determination (OD) may be done on the ground in a post-processing mode or in real-time on board a satellite and may be accomplished days, hours or immediately after observations are processed. The Global Positioning System (GPS) is now widely used as an alternative to ground tracking resources to supply observation data for satellite positioning and navigation. GPS is accurate, inexpensive, provides continuous coverage, and is an excellent choice for autonomous systems. In an effort to estimate precise satellite ephemeris in real-time on board a satellite, the Goddard Space Flight Center (GSFC) created the GPS Enhanced OD Experiment (GEODE) flight navigation software. This dissertation offers alternative methods and improvements to GEODE to increase on board autonomy and real-time total position accuracy and precision without increasing computational burden. First, GEODE is modified to include a Gravity Acceleration Approximation Function (GAAF) to replace the traditional spherical harmonic representation of the gravity field. Next, an ionospheric correction method called Differenced Range Versus Integrated Doppler (DRVID) is applied to correct for ionospheric errors in the GPS measurements used in GEODE. Then, Dynamic Model Compensation (DMC) is added to estimate unmodeled and/or mismodeled forces in the dynamic model and to provide an alternative process noise variance-covariance formulation. Finally, a Genetic Algorithm (GA) is implemented in the form of Genetic Model Compensation (GMC) to optimize DMC forcing noise parameters. Application of GAAF, DRVID and DMC improved GEODE's position estimates by 28.3% when applied to GPS/MET data collected in the presence of Selective Availability (SA), 17.5% when SA is removed from the GPS

  14. Proton Radii of 4,6,8He Isotopes from High-Precision Nucleon-Nucleon Interactions

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

    Caurier, E; Navratil, P

    2005-11-16

    Recently, precision laser spectroscopy on {sup 6}He atoms determined accurately the isotope shift between {sup 4}He and {sup 6}He and, consequently, the charge radius of {sup 6}He. A similar experiment for {sup 8}He is under way. We have performed large-scale ab initio calculations for {sup 4,6,8}He isotopes using high-precision nucleon-nucleon (NN) interactions within the no-core shell model (NCSM) approach. With the CD-Bonn 2000 NN potential we found point-proton root-mean-square (rms) radii of {sup 4}He and {sup 6}He 1.45(1) fm and 1.89(4), respectively, in agreement with experiment and predict the {sup 8}He point proton rms radius to be 1.88(6) fm. Atmore » the same time, our calculations show that the recently developed nonlocal INOY NN potential gives binding energies closer to experiment, but underestimates the charge radii.« less

  15. CHEOPS: a space telescope for ultra-high precision photometry of exoplanet transits

    NASA Astrophysics Data System (ADS)

    Cessa, V.; Beck, T.; Benz, W.; Broeg, C.; Ehrenreich, D.; Fortier, A.; Peter, G.; Magrin, D.; Pagano, I.; Plesseria, J.-Y.; Steller, M.; Szoke, J.; Thomas, N.; Ragazzoni, R.; Wildi, F.

    2017-11-01

    The CHaracterising ExOPlanet Satellite (CHEOPS) is a joint ESA-Switzerland space mission dedicated to search for exoplanet transits by means of ultra-high precision photometry whose launch readiness is expected end 2017. The CHEOPS instrument will be the first space telescope dedicated to search for transits on bright stars already known to host planets. By being able to point at nearly any location on the sky, it will provide the unique capability of determining accurate radii for a subset of those planets for which the mass has already been estimated from ground-based spectroscopic surveys. CHEOPS will also provide precision radii for new planets discovered by the next generation ground-based transits surveys (Neptune-size and smaller). The main science goals of the CHEOPS mission will be to study the structure of exoplanets with radii typically ranging from 1 to 6 Earth radii orbiting bright stars. With an accurate knowledge of masses and radii for an unprecedented sample of planets, CHEOPS will set new constraints on the structure and hence on the formation and evolution of planets in this mass range. To reach its goals CHEOPS will measure photometric signals with a precision of 20 ppm in 6 hours of integration time for a 9th magnitude star. This corresponds to a signal to noise of 5 for a transit of an Earth-sized planet orbiting a solar-sized star (0.9 solar radii). This precision will be achieved by using a single frame-transfer backside illuminated CCD detector cool down at 233K and stabilized within {10 mK . The CHEOPS optical design is based on a Ritchey-Chretien style telescope with 300 mm effective aperture diameter, which provides a defocussed image of the target star while minimizing straylight using a dedicated field stop and baffle system. As CHEOPS will be in a LEO orbit, straylight suppression is a key point to allow the observation of faint stars. The telescope will be the only payload on a spacecraft platform providing pointing stability of < 8

  16. Precision digital control systems

    NASA Astrophysics Data System (ADS)

    Vyskub, V. G.; Rozov, B. S.; Savelev, V. I.

    This book is concerned with the characteristics of digital control systems of great accuracy. A classification of such systems is considered along with aspects of stabilization, programmable control applications, digital tracking systems and servomechanisms, and precision systems for the control of a scanning laser beam. Other topics explored are related to systems of proportional control, linear devices and methods for increasing precision, approaches for further decreasing the response time in the case of high-speed operation, possibilities for the implementation of a logical control law, and methods for the study of precision digital control systems. A description is presented of precision automatic control systems which make use of electronic computers, taking into account the existing possibilities for an employment of computers in automatic control systems, approaches and studies required for including a computer in such control systems, and an analysis of the structure of automatic control systems with computers. Attention is also given to functional blocks in the considered systems.

  17. Toward precision medicine and health: Opportunities and challenges in allergic diseases.

    PubMed

    Galli, Stephen Joseph

    2016-05-01

    Precision medicine (also called personalized, stratified, or P4 medicine) can be defined as the tailoring of preventive measures and medical treatments to the characteristics of each patient to obtain the best clinical outcome for each person while ideally also enhancing the cost-effectiveness of such interventions for patients and society. Clearly, the best clinical outcome for allergic diseases is not to get them in the first place. To emphasize the importance of disease prevention, a critical component of precision medicine can be referred to as precision health, which is defined herein as the use of all available information pertaining to specific subjects (including family history, individual genetic and other biometric information, and exposures to risk factors for developing or exacerbating disease), as well as features of their environments, to sustain and enhance health and prevent the development of disease. In this article I will provide a personal perspective on how the precision health-precision medicine approach can be applied to the related goals of preventing the development of allergic disorders and providing the most effective diagnosis, disease monitoring, and care for those with these prevalent diseases. I will also mention some of the existing and potential challenges to achieving these ambitious goals. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  18. Accurate and consistent automatic seismocardiogram annotation without concurrent ECG.

    PubMed

    Laurin, A; Khosrow-Khavar, F; Blaber, A P; Tavakolian, Kouhyar

    2016-09-01

    Seismocardiography (SCG) is the measurement of vibrations in the sternum caused by the beating of the heart. Precise cardiac mechanical timings that are easily obtained from SCG are critically dependent on accurate identification of fiducial points. So far, SCG annotation has relied on concurrent ECG measurements. An algorithm capable of annotating SCG without the use any other concurrent measurement was designed. We subjected 18 participants to graded lower body negative pressure. We collected ECG and SCG, obtained R peaks from the former, and annotated the latter by hand, using these identified peaks. We also annotated the SCG automatically. We compared the isovolumic moment timings obtained by hand to those obtained using our algorithm. Mean  ±  confidence interval of the percentage of accurately annotated cardiac cycles were [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] for levels of negative pressure 0, -20, -30, -40, and  -50 mmHg. LF/HF ratios, the relative power of low-frequency variations to high-frequency variations in heart beat intervals, obtained from isovolumic moments were also compared to those obtained from R peaks. The mean differences  ±  confidence interval were [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] for increasing levels of negative pressure. The accuracy and consistency of the algorithm enables the use of SCG as a stand-alone heart monitoring tool in healthy individuals at rest, and could serve as a basis for an eventual application in pathological cases.

  19. Precise determination of lattice phase shifts and mixing angles

    DOE PAGES

    Lu, Bing -Nan; Lähde, Timo A.; Lee, Dean; ...

    2016-07-09

    Here, we introduce a general and accurate method for determining lattice phase shifts and mixing angles, which is applicable to arbitrary, non-cubic lattices. Our method combines angular momentum projection, spherical wall boundaries and an adjustable auxiliary potential. This allows us to construct radial lattice wave functions and to determine phase shifts at arbitrary energies. For coupled partial waves, we use a complex-valued auxiliary potential that breaks time-reversal invariance. We benchmark our method using a system of two spin-1/2 particles interacting through a finite-range potential with a strong tensor component. We are able to extract phase shifts and mixing angles formore » all angular momenta and energies, with precision greater than that of extant methods. We discuss a wide range of applications from nuclear lattice simulations to optical lattice experiments.« less

  20. Raman fingerprints of atomically precise graphene nanoribbons

    DOE PAGES

    Verzhbitskiy, Ivan A.; Corato, Marzio De; Ruini, Alice; ...

    2016-02-23

    Bottom-up approaches allow the production of ultranarrow and atomically precise graphene nanoribbons (GNRs) with electronic and optical properties controlled by the specific atomic structure. Combining Raman spectroscopy and ab initio simulations, we show that GNR width, edge geometry, and functional groups all influence their Raman spectra. As a result, the low-energy spectral region below 1000 cm –1 is particularly sensitive to edge morphology and functionalization, while the D peak dispersion can be used to uniquely fingerprint the presence of GNRs and differentiates them from other sp 2 carbon nanostructures.