Large Display Interaction Using Mobile Devices

OpenAIRE

Bauer, Jens

2015-01-01

Large displays become more and more popular, due to dropping prices. Their size and high resolution leverages collaboration and they are capable of dis- playing even large datasets in one view. This becomes even more interesting as the number of big data applications increases. The increased screen size and other properties of large displays pose new challenges to the Human- Computer-Interaction with these screens. This includes issues such as limited scalability to the number of users, diver...

Large-scale DNA Barcode Library Generation for Biomolecule Identification in High-throughput Screens.

Science.gov (United States)

Lyons, Eli; Sheridan, Paul; Tremmel, Georg; Miyano, Satoru; Sugano, Sumio

2017-10-24

High-throughput screens allow for the identification of specific biomolecules with characteristics of interest. In barcoded screens, DNA barcodes are linked to target biomolecules in a manner allowing for the target molecules making up a library to be identified by sequencing the DNA barcodes using Next Generation Sequencing. To be useful in experimental settings, the DNA barcodes in a library must satisfy certain constraints related to GC content, homopolymer length, Hamming distance, and blacklisted subsequences. Here we report a novel framework to quickly generate large-scale libraries of DNA barcodes for use in high-throughput screens. We show that our framework dramatically reduces the computation time required to generate large-scale DNA barcode libraries, compared with a naїve approach to DNA barcode library generation. As a proof of concept, we demonstrate that our framework is able to generate a library consisting of one million DNA barcodes for use in a fragment antibody phage display screening experiment. We also report generating a general purpose one billion DNA barcode library, the largest such library yet reported in literature. Our results demonstrate the value of our novel large-scale DNA barcode library generation framework for use in high-throughput screening applications.

Thermocapillary Bubble Migration: Thermal Boundary Layers for Large Marangoni Numbers

Science.gov (United States)

Balasubramaniam, R.; Subramanian, R. S.

1996-01-01

The migration of an isolated gas bubble in an immiscible liquid possessing a temperature gradient is analyzed in the absence of gravity. The driving force for the bubble motion is the shear stress at the interface which is a consequence of the temperature dependence of the surface tension. The analysis is performed under conditions for which the Marangoni number is large, i.e. energy is transferred predominantly by convection. Velocity fields in the limit of both small and large Reynolds numbers are used. The thermal problem is treated by standard boundary layer theory. The outer temperature field is obtained in the vicinity of the bubble. A similarity solution is obtained for the inner temperature field. For both small and large Reynolds numbers, the asymptotic values of the scaled migration velocity of the bubble in the limit of large Marangoni numbers are calculated. The results show that the migration velocity has the same scaling for both low and large Reynolds numbers, but with a different coefficient. Higher order thermal boundary layers are analyzed for the large Reynolds number flow field and the higher order corrections to the migration velocity are obtained. Results are also presented for the momentum boundary layer and the thermal wake behind the bubble, for large Reynolds number conditions.

Cancer screening is not only about numbers

NARCIS (Netherlands)

Knottnerus, B. J.

2017-01-01

In the cancer screening debate, arguments for and against screening are often based on statistics, whereas for individuals personal, non-statistical factors are at least as important when deciding whether to participate in screening. Health care professionals have a responsibility in helping

Reconfiguring Cooperative Work by Visualizing EPR on Large Projected Screens

DEFF Research Database (Denmark)

Simonsen, Jesper

Simonsen, J. (2006): Reconfiguring Cooperative Work by Visualizing EPR on Large Projected Screens, Paper presented at the PDC 2006 workshop on: Reconfiguring Healthcare: Issues in Computer Supported Cooperative Work in Healthcare Environments. Participatory Design Conference, Trento, Italy, August...

Large-screen display industry: market and technology trends for direct view and projection displays

Science.gov (United States)

Castellano, Joseph A.; Mentley, David E.

1996-03-01

Large screen information displays are defined as dynamic electronic displays that can be viewed by more than one person and are at least 2-feet wide. These large area displays for public viewing provide convenience, entertainment, security, and efficiency to the viewers. There are numerous uses for large screen information displays including those in advertising, transportation, traffic control, conference room presentations, computer aided design, banking, and military command/control. A noticeable characteristic of the large screen display market is the interchangeability of display types. For any given application, the user can usually choose from at least three alternative technologies, and sometimes from many more. Some display types have features that make them suitable for specific applications due to temperature, brightness, power consumption, or other such characteristic. The overall worldwide unit consumption of large screen information displays of all types and for all applications (excluding consumer TV) will increase from 401,109 units in 1995 to 655,797 units in 2002. On a unit consumption basis, applications in business and education represent the largest share of unit consumption over this time period; in 1995, this application represented 69.7% of the total. The market (value of shipments) will grow from DOL3.1 billion in 1995 to DOL3.9 billion in 2002. The market will be dominated by front LCD projectors and LCD overhead projector plates.

A Chain Perspective on Large-scale Number Systems

NARCIS (Netherlands)

Grijpink, J.H.A.M.

2012-01-01

As large-scale number systems gain significance in social and economic life (electronic communication, remote electronic authentication), the correct functioning and the integrity of public number systems take on crucial importance. They are needed to uniquely indicate people, objects or phenomena

Large numbers hypothesis. II - Electromagnetic radiation

Science.gov (United States)

Adams, P. J.

1983-01-01

This paper develops the theory of electromagnetic radiation in the units covariant formalism incorporating Dirac's large numbers hypothesis (LNH). A direct field-to-particle technique is used to obtain the photon propagation equation which explicitly involves the photon replication rate. This replication rate is fixed uniquely by requiring that the form of a free-photon distribution function be preserved, as required by the 2.7 K cosmic radiation. One finds that with this particular photon replication rate the units covariant formalism developed in Paper I actually predicts that the ratio of photon number to proton number in the universe varies as t to the 1/4, precisely in accord with LNH. The cosmological red-shift law is also derived and it is shown to differ considerably from the standard form of (nu)(R) - const.

Lepton number violation in theories with a large number of standard model copies

International Nuclear Information System (INIS)

Kovalenko, Sergey; Schmidt, Ivan; Paes, Heinrich

2011-01-01

We examine lepton number violation (LNV) in theories with a saturated black hole bound on a large number of species. Such theories have been advocated recently as a possible solution to the hierarchy problem and an explanation of the smallness of neutrino masses. On the other hand, the violation of the lepton number can be a potential phenomenological problem of this N-copy extension of the standard model as due to the low quantum gravity scale black holes may induce TeV scale LNV operators generating unacceptably large rates of LNV processes. We show, however, that this issue can be avoided by introducing a spontaneously broken U 1(B-L) . Then, due to the existence of a specific compensation mechanism between contributions of different Majorana neutrino states, LNV processes in the standard model copy become extremely suppressed with rates far beyond experimental reach.

Large-scale Topographical Screen for Investigation of Physical Neural-Guidance Cues

Science.gov (United States)

Li, Wei; Tang, Qing Yuan; Jadhav, Amol D.; Narang, Ankit; Qian, Wei Xian; Shi, Peng; Pang, Stella W.

2015-03-01

A combinatorial approach was used to present primary neurons with a large library of topographical features in the form of micropatterned substrate for high-throughput screening of physical neural-guidance cues that can effectively promote different aspects of neuronal development, including axon and dendritic outgrowth. Notably, the neuronal-guidance capability of specific features was automatically identified using a customized image processing software, thus significantly increasing the screening throughput with minimal subjective bias. Our results indicate that the anisotropic topographies promote axonal and in some cases dendritic extension relative to the isotropic topographies, while dendritic branching showed preference to plain substrates over the microscale features. The results from this work can be readily applied towards engineering novel biomaterials with precise surface topography that can serve as guidance conduits for neuro-regenerative applications. This novel topographical screening strategy combined with the automated processing capability can also be used for high-throughput screening of chemical or genetic regulatory factors in primary neurons.

Screening for common copy-number variants in cancer genes.

Science.gov (United States)

Tyson, Jess; Majerus, Tamsin M O; Walker, Susan; Armour, John A L

2010-12-01

For most cases of colorectal cancer that arise without a family history of the disease, it is proposed that an appreciable heritable component of predisposition is the result of contributions from many loci. Although progress has been made in identifying single nucleotide variants associated with colorectal cancer risk, the involvement of low-penetrance copy number variants is relatively unexplored. We have used multiplex amplifiable probe hybridization (MAPH) in a fourfold multiplex (QuadMAPH), positioned at an average resolution of one probe per 2 kb, to screen a total of 1.56 Mb of genomic DNA for copy number variants around the genes APC, AXIN1, BRCA1, BRCA2, CTNNB1, HRAS, MLH1, MSH2, and TP53. Two deletion events were detected, one upstream of MLH1 in a control individual and the other in APC in a colorectal cancer patient, but these do not seem to correspond to copy number polymorphisms with measurably high population frequencies. In summary, by means of our QuadMAPH assay, copy number measurement data were of sufficient resolution and accuracy to detect any copy number variants with high probability. However, this study has demonstrated a very low incidence of deletion and duplication variants within intronic and flanking regions of these nine genes, in both control individuals and colorectal cancer patients. Copyright © 2010 Elsevier Inc. All rights reserved.

Comparative analysis of machine learning methods in ligand-based virtual screening of large compound libraries.

Science.gov (United States)

Ma, Xiao H; Jia, Jia; Zhu, Feng; Xue, Ying; Li, Ze R; Chen, Yu Z

2009-05-01

Machine learning methods have been explored as ligand-based virtual screening tools for facilitating drug lead discovery. These methods predict compounds of specific pharmacodynamic, pharmacokinetic or toxicological properties based on their structure-derived structural and physicochemical properties. Increasing attention has been directed at these methods because of their capability in predicting compounds of diverse structures and complex structure-activity relationships without requiring the knowledge of target 3D structure. This article reviews current progresses in using machine learning methods for virtual screening of pharmacodynamically active compounds from large compound libraries, and analyzes and compares the reported performances of machine learning tools with those of structure-based and other ligand-based (such as pharmacophore and clustering) virtual screening methods. The feasibility to improve the performance of machine learning methods in screening large libraries is discussed.

Examination of the lumbar vertebral column using large-screen image intensifier photofluorography

Energy Technology Data Exchange (ETDEWEB)

Soimakallio, S.; Manninen, H.; Mahlamaeki, S.

1985-01-01

The OPTILUX 57 device with its large image intensifying screen is very efficient in visualizing the lumbar vertebrae. The article explains the techniques and summarizes results obtained in the examination of young sportsmen.

Fatal crashes involving large numbers of vehicles and weather.

Science.gov (United States)

Wang, Ying; Liang, Liming; Evans, Leonard

2017-12-01

Adverse weather has been recognized as a significant threat to traffic safety. However, relationships between fatal crashes involving large numbers of vehicles and weather are rarely studied according to the low occurrence of crashes involving large numbers of vehicles. By using all 1,513,792 fatal crashes in the Fatality Analysis Reporting System (FARS) data, 1975-2014, we successfully described these relationships. We found: (a) fatal crashes involving more than 35 vehicles are most likely to occur in snow or fog; (b) fatal crashes in rain are three times as likely to involve 10 or more vehicles as fatal crashes in good weather; (c) fatal crashes in snow [or fog] are 24 times [35 times] as likely to involve 10 or more vehicles as fatal crashes in good weather. If the example had used 20 vehicles, the risk ratios would be 6 for rain, 158 for snow, and 171 for fog. To reduce the risk of involvement in fatal crashes with large numbers of vehicles, drivers should slow down more than they currently do under adverse weather conditions. Driver deaths per fatal crash increase slowly with increasing numbers of involved vehicles when it is snowing or raining, but more steeply when clear or foggy. We conclude that in order to reduce risk of involvement in crashes involving large numbers of vehicles, drivers must reduce speed in fog, and in snow or rain, reduce speed by even more than they already do. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

Examination of the lumbar vertebral column using large-screen image intensifier photofluorography

International Nuclear Information System (INIS)

Soimakallio, S.; Manninen, H.; Mahlamaeki, S.; Kuopio Central Hospital

1985-01-01

The OPTILUX 57 device with its large image intensifying screen is very efficient in visualizing the lumbar vertebrae. The article explains the techniques and summarizes results obtained in the examination of young sportsmen. (orig.) [de

Travel Times for Screening Mammography: Impact of Geographic Expansion by a Large Academic Health System.

Science.gov (United States)

Rosenkrantz, Andrew B; Liang, Yu; Duszak, Richard; Recht, Michael P

2017-09-01

This study aims to assess the impact of off-campus facility expansion by a large academic health system on patient travel times for screening mammography. Screening mammograms performed from 2013 to 2015 and associated patient demographics were identified using the NYU Langone Medical Center Enterprise Data Warehouse. During this time, the system's number of mammography facilities increased from 6 to 19, reflecting expansion beyond Manhattan throughout the New York metropolitan region. Geocoding software was used to estimate driving times from patients' homes to imaging facilities. For 147,566 screening mammograms, the mean estimated patient travel time was 19.9 ± 15.2 minutes. With facility expansion, travel times declined significantly (P travel times between such subgroups. However, travel times to pre-expansion facilities remained stable (initial: 26.8 ± 18.9 minutes, final: 26.7 ± 18.6 minutes). Among women undergoing mammography before and after expansion, travel times were shorter for the postexpansion mammogram in only 6.3%, but this rate varied significantly (all P travel burden and reduce travel time variation among sociodemographic populations. Nonetheless, existing patients strongly tend to return to established facilities despite potentially shorter travel time locations, suggesting strong site loyalty. Variation in travel times likely relates to various factors other than facility proximity. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Electronic screens in children's bedrooms and adiposity, physical activity and sleep: do the number and type of electronic devices matter?

Science.gov (United States)

Chaput, Jean-Philippe; Leduc, Geneviève; Boyer, Charles; Bélanger, Priscilla; LeBlanc, Allana G; Borghese, Michael M; Tremblay, Mark S

2014-07-11

To examine whether the number and type of electronic screens available in children's bedrooms matter in their relationship to adiposity, physical activity and sleep. A cross-sectional study was conducted involving 502 children aged 9-11 years from Ottawa, Ontario. The presence (yes/no) of a television (TV), computer or video game system in the child's bedroom was reported by the parents. Percentage body fat was measured using bioelectrical impedance. An accelerometer was worn over seven days to assess moderate-to-vigorous physical activity (MVPA), total sedentary time, sleep duration and sleep efficiency. Screen time was self-reported by the child. After adjustment for age, sex, ethnicity, annual household income and highest level of parental education, children with 2-3 screens in their bedroom had a significantly higher percentage of body fat than children with no screen in their bedroom. However, while children with 2-3 screens in their bedroom engaged in more screen time overall than those with no screen, total sedentary time and MVPA were not significantly different. Sleep duration was not related to the number of screens in the bedroom, but sleep efficiency was significantly lower in children with at least 2 screens in the bedroom. Finally, children having only a TV in their bedroom had significantly higher adiposity than those having no screen at all. In contrast, the presence of a computer in children's bedrooms was not associated with higher adiposity than that of children with no screen. A higher number of screens in a child's bedroom was associated with higher adiposity, more total screen time and lower sleep efficiency. Having a TV in the bedroom appears to be the type of screen presence associated with higher levels of adiposity. Given the popularity of screens among children, these findings are increasingly relevant to health promotion strategies.

On a strong law of large numbers for monotone measures

Czech Academy of Sciences Publication Activity Database

Agahi, H.; Mohammadpour, A.; Mesiar, Radko; Ouyang, Y.

2013-01-01

Roč. 83, č. 4 (2013), s. 1213-1218 ISSN 0167-7152 R&D Projects: GA ČR GAP402/11/0378 Institutional support: RVO:67985556 Keywords : capacity * Choquet integral * strong law of large numbers Subject RIV: BA - General Mathematics Impact factor: 0.531, year: 2013 http://library.utia.cas.cz/separaty/2013/E/mesiar-on a strong law of large numbers for monotone measures.pdf

Crunching Numbers: What Cancer Screening Statistics Really Tell Us

Science.gov (United States)

Cancer screening studies have shown that more screening does not necessarily translate into fewer cancer deaths. This article explains how to interpret the statistics used to describe the results of screening studies.

The large numbers hypothesis and a relativistic theory of gravitation

International Nuclear Information System (INIS)

Lau, Y.K.; Prokhovnik, S.J.

1986-01-01

A way to reconcile Dirac's large numbers hypothesis and Einstein's theory of gravitation was recently suggested by Lau (1985). It is characterized by the conjecture of a time-dependent cosmological term and gravitational term in Einstein's field equations. Motivated by this conjecture and the large numbers hypothesis, we formulate here a scalar-tensor theory in terms of an action principle. The cosmological term is required to be spatially dependent as well as time dependent in general. The theory developed is appled to a cosmological model compatible with the large numbers hypothesis. The time-dependent form of the cosmological term and the scalar potential are then deduced. A possible explanation of the smallness of the cosmological term is also given and the possible significance of the scalar field is speculated

Rotating thermal convection at very large Rayleigh numbers

Science.gov (United States)

Weiss, Stephan; van Gils, Dennis; Ahlers, Guenter; Bodenschatz, Eberhard

2016-11-01

The large scale thermal convection systems in geo- and astrophysics are usually influenced by Coriolis forces caused by the rotation of their celestial bodies. To better understand the influence of rotation on the convective flow field and the heat transport at these conditions, we study Rayleigh-Bénard convection, using pressurized sulfur hexaflouride (SF6) at up to 19 bars in a cylinder of diameter D=1.12 m and a height of L=2.24 m. The gas is heated from below and cooled from above and the convection cell sits on a rotating table inside a large pressure vessel (the "Uboot of Göttingen"). With this setup Rayleigh numbers of up to Ra =1015 can be reached, while Ekman numbers as low as Ek =10-8 are possible. The Prandtl number in these experiment is kept constant at Pr = 0 . 8 . We report on heat flux measurements (expressed by the Nusselt number Nu) as well as measurements from more than 150 temperature probes inside the flow. We thank the Deutsche Forschungsgemeinschaft (DFG) for financial support through SFB963: "Astrophysical Flow Instabilities and Turbulence". The work of GA was supported in part by the US National Science Foundation through Grant DMR11-58514.

Concurrent Driving Method with Fast Scan Rate for Large Mutual Capacitance Touch Screens

Directory of Open Access Journals (Sweden)

Mohamed Gamal Ahmed Mohamed

2015-01-01

Full Text Available A novel touch screen control technique is introduced, which scans each frame in two steps of concurrent multichannel driving and differential sensing. The proposed technique substantially increases the scan rate and reduces the ambient noise effectively. It is also extended to a multichip architecture to support excessively large touch screens with great scan rate improvement. The proposed method has been implemented using 0.18 μm CMOS TowerJazz process and tested with FPGA and AFE board connecting a 23-inch touch screen. Experimental results show a scan rate improvement of up to 23.8 times and an SNR improvement of 24.6 dB over the conventional method.

Collaborative Work without Large, Shared Displays: Looking for “the Big Picture” on a Small Screen?

DEFF Research Database (Denmark)

Hertzum, Morten

2017-01-01

Large, shared displays – such as electronic whiteboards – have proven successful in supporting actors in forming and maintaining an overview of tightly coupled collaborative activities. However, in many developing countries the technology of choice is mobile phones, which have neither a large nor...... a shared screen. It therefore appears relevant to ask: How may mobile devices with small screens support, or fail to support, actors in forming and maintaining an overview of their collaborative activities?...

A web-based platform for virtual screening.

Science.gov (United States)

Watson, Paul; Verdonk, Marcel; Hartshorn, Michael J

2003-09-01

A fully integrated, web-based, virtual screening platform has been developed to allow rapid virtual screening of large numbers of compounds. ORACLE is used to store information at all stages of the process. The system includes a large database of historical compounds from high throughput screenings (HTS) chemical suppliers, ATLAS, containing over 3.1 million unique compounds with their associated physiochemical properties (ClogP, MW, etc.). The database can be screened using a web-based interface to produce compound subsets for virtual screening or virtual library (VL) enumeration. In order to carry out the latter task within ORACLE a reaction data cartridge has been developed. Virtual libraries can be enumerated rapidly using the web-based interface to the cartridge. The compound subsets can be seamlessly submitted for virtual screening experiments, and the results can be viewed via another web-based interface allowing ad hoc querying of the virtual screening data stored in ORACLE.

Attitude stabilization of a spacecraft equipped with large electrostatic protection screens

Science.gov (United States)

Nikitin, D. Yu.; Tikhonov, A. A.

2018-05-01

A satellite with a system of three electrostatic radiation protection (ERP) screens is under consideration. The screens are constructed as electrostatically charged toroidal shields with characteristic size of order equal to 100 m. The interaction of electric charge with the Earth's magnetic field (EMF) give rise to the Lorentz torque acting upon a satellite attitude motion. As the sizes of ERP system are large, we derive the Lorentz torque taking into account the complex form of ERP screens and gradient of the EMF in the screen volume. It is assumed that the satellite center of charge coincides with the satellite mass center. The EMF is modeled by the straight magnetic dipole. In the paper we investigate the usage of Lorentz torque for passive attitude stabilization for satellite in a circular equatorial orbit. Mathematical model for attitude dynamics of a satellite equipped with ERP interacting with the EMF is derived and first integral of corresponding differential equations is constructed. The straight equilibrium position of the satellite in the orbital frame is found. Sufficient conditions for stability of satellite equilibrium position are constructed with the use of the first integral. The gravity gradient torque is taken into account. The satellite equilibrium stability domain is constructed.

Proportional incidence and radiological review of large (T2+) breast cancers as surrogate indicators of screening programme performance

International Nuclear Information System (INIS)

Ciatto, S.; Bernardi, D.; Pellegrini, M.; Borsato, G.; Peterlongo, P.; Gentilini, M.A.; Caumo, F.; Frigerio, A.; Houssami, N.

2012-01-01

Surrogate measures of screening performance [e.g. interval cancer (IC) proportional incidence] allow timely monitoring of sensitivity and quality. This study explored measures using large (T2+) breast cancers as potential indicators of screening performance. The proportional incidence of T2+ cancers (observed/expected cases) in a population-based screening programme (Trento, 2001-2009) was estimated. A parallel review of 'negative' preceding mammograms for screen-detected T2+ and for all ICs, using 'blinded' independent readings and case-mixes (54 T2+, 50 ICs, 170 controls) was also performed. T2+ cancers were observed in 168 screening participants: 48 at first screen, 67 at repeat screening and 53 ICs. The T2+ estimated proportional incidence was 68% (observed/expected = 168/247), corresponding to an estimated 32% reduction in the rate of T2+ cancers in screening participants relative to that expected without screening. Majority review classified 27.8% (15/54) of T2+ and 28% (14/50) of ICs as screening error (P = 0.84), with variable recall rates amongst radiologists (8.8-15.2%). T2+ review could be integrated as part of quality monitoring and potentially prove more feasible than IC review for some screening services. circle Interval breast cancers, assumed as screening failures, are monitored to estimate screening performance circle Large (T2+) cancers at screening may also represent failed prior screening detection circle Analysis of T2+ lesions may be more feasible than assessing interval cancers circle Analysis of T2+ cancers is a potential further measure of screening performance. (orig.)

Proportional incidence and radiological review of large (T2+) breast cancers as surrogate indicators of screening programme performance

Energy Technology Data Exchange (ETDEWEB)

Ciatto, S.; Bernardi, D.; Pellegrini, M.; Borsato, G.; Peterlongo, P. [APSS, U.O. Senologia Clinica e Screening Mammografico, Dipartimento di Radiodiagnostica, Trento (Italy); Gentilini, M.A. [APSS, Servizio Osservatorio Epidemiologico, Direzione promozione ed educazione alla salute, Trento (Italy); Caumo, F. [Centro di Prevenzione Senologica, Verona (Italy); Frigerio, A. [CRR, Centro di Riferimento Regionale per lo Screening Mammografico, Torino (Italy); Houssami, N. [University of Sydney, Screening and Test Evaluation Program, School of Public Health, Sydney Medical School, Sydney (Australia)

2012-06-15

Surrogate measures of screening performance [e.g. interval cancer (IC) proportional incidence] allow timely monitoring of sensitivity and quality. This study explored measures using large (T2+) breast cancers as potential indicators of screening performance. The proportional incidence of T2+ cancers (observed/expected cases) in a population-based screening programme (Trento, 2001-2009) was estimated. A parallel review of 'negative' preceding mammograms for screen-detected T2+ and for all ICs, using 'blinded' independent readings and case-mixes (54 T2+, 50 ICs, 170 controls) was also performed. T2+ cancers were observed in 168 screening participants: 48 at first screen, 67 at repeat screening and 53 ICs. The T2+ estimated proportional incidence was 68% (observed/expected = 168/247), corresponding to an estimated 32% reduction in the rate of T2+ cancers in screening participants relative to that expected without screening. Majority review classified 27.8% (15/54) of T2+ and 28% (14/50) of ICs as screening error (P = 0.84), with variable recall rates amongst radiologists (8.8-15.2%). T2+ review could be integrated as part of quality monitoring and potentially prove more feasible than IC review for some screening services. circle Interval breast cancers, assumed as screening failures, are monitored to estimate screening performance circle Large (T2+) cancers at screening may also represent failed prior screening detection circle Analysis of T2+ lesions may be more feasible than assessing interval cancers circle Analysis of T2+ cancers is a potential further measure of screening performance. (orig.)

Large screen mimic display design research for advanced main control room in nuclear power plant

International Nuclear Information System (INIS)

Zheng Mingguang; Yang Yanhua; Xu Jijun; Zhang Qinshun; Ning Zhonghe

2002-01-01

Firstly the evolution of mimic diagrams or displays used in the main control room of nuclear power plant was introduced. The active functions of mimic diagrams were analyzed on the release of operator psychological burden and pressure, the assistance of operator for the information searching, status understanding, manual actuation, correct decision making as well as the safe and reliable operation of the nuclear power plant. The importance and necessity to use the (large screen) mimic diagrams in advanced main control room of nuclear power plant, the design principle, design details and verification measures of large screen mimic display are also described

Forecasting distribution of numbers of large fires

Science.gov (United States)

Eidenshink, Jeffery C.; Preisler, Haiganoush K.; Howard, Stephen; Burgan, Robert E.

2014-01-01

Systems to estimate forest fire potential commonly utilize one or more indexes that relate to expected fire behavior; however they indicate neither the chance that a large fire will occur, nor the expected number of large fires. That is, they do not quantify the probabilistic nature of fire danger. In this work we use large fire occurrence information from the Monitoring Trends in Burn Severity project, and satellite and surface observations of fuel conditions in the form of the Fire Potential Index, to estimate two aspects of fire danger: 1) the probability that a 1 acre ignition will result in a 100+ acre fire, and 2) the probabilities of having at least 1, 2, 3, or 4 large fires within a Predictive Services Area in the forthcoming week. These statistical processes are the main thrust of the paper and are used to produce two daily national forecasts that are available from the U.S. Geological Survey, Earth Resources Observation and Science Center and via the Wildland Fire Assessment System. A validation study of our forecasts for the 2013 fire season demonstrated good agreement between observed and forecasted values.

Teaching Multiplication of Large Positive Whole Numbers Using ...

African Journals Online (AJOL)

This study investigated the teaching of multiplication of large positive whole numbers using the grating method and the effect of this method on students' performance in junior secondary schools. The study was conducted in Obio Akpor Local Government Area of Rivers state. It was quasi- experimental. Two research ...

Screening cotton genotypes for seedling drought tolerance

Directory of Open Access Journals (Sweden)

Penna Julio C. Viglioni

1998-01-01

Full Text Available The objectives of this study were to adapt a screening method previously used to assess seedling drought tolerance in cereals for use in cotton (Gossypium hirsutum L. and to identify tolerant accessions among a wide range of genotypes. Ninety genotypes were screened in seven growth chamber experiments. Fifteen-day-old seedlings were subjected to four 4-day drought cycles, and plant survival was evaluated after each cycle. Three cycles are probably the minimum required in cotton work. Significant differences (at the 0.05 level or lower among entries were obtained in four of the seven experiments. A "confirmation test" with entries previously evaluated as "tolerant" (high survival and "susceptible" (low survival was run. A number of entries duplicated their earlier performance, but others did not, which indicates the need to reevaluate selections. Germplasms considered tolerant included: `IAC-13-1', `IAC-RM4-SM5', `Minas Sertaneja', `Acala 1517E-1' and `4521'. In general, the technique is simple, though time-consuming, with practical value for screening a large number of genotypes. Results from the screening tests generally agreed with field information. The screening procedure is suitable to select tolerant accessions from among a large number of entries in germplasm collections as a preliminary step in breeding for drought tolerance. This research also demonstrated the need to characterize the internal lack of uniformity in growth chambers to allow for adequate designs of experiments.

Screen-Space Normal Distribution Function Caching for Consistent Multi-Resolution Rendering of Large Particle Data

KAUST Repository

Ibrahim, Mohamed

2017-08-28

Molecular dynamics (MD) simulations are crucial to investigating important processes in physics and thermodynamics. The simulated atoms are usually visualized as hard spheres with Phong shading, where individual particles and their local density can be perceived well in close-up views. However, for large-scale simulations with 10 million particles or more, the visualization of large fields-of-view usually suffers from strong aliasing artifacts, because the mismatch between data size and output resolution leads to severe under-sampling of the geometry. Excessive super-sampling can alleviate this problem, but is prohibitively expensive. This paper presents a novel visualization method for large-scale particle data that addresses aliasing while enabling interactive high-quality rendering. We introduce the novel concept of screen-space normal distribution functions (S-NDFs) for particle data. S-NDFs represent the distribution of surface normals that map to a given pixel in screen space, which enables high-quality re-lighting without re-rendering particles. In order to facilitate interactive zooming, we cache S-NDFs in a screen-space mipmap (S-MIP). Together, these two concepts enable interactive, scale-consistent re-lighting and shading changes, as well as zooming, without having to re-sample the particle data. We show how our method facilitates the interactive exploration of real-world large-scale MD simulation data in different scenarios.

Screen-Space Normal Distribution Function Caching for Consistent Multi-Resolution Rendering of Large Particle Data

KAUST Repository

Ibrahim, Mohamed; Wickenhauser, Patrick; Rautek, Peter; Reina, Guido; Hadwiger, Markus

2017-01-01

Molecular dynamics (MD) simulations are crucial to investigating important processes in physics and thermodynamics. The simulated atoms are usually visualized as hard spheres with Phong shading, where individual particles and their local density can be perceived well in close-up views. However, for large-scale simulations with 10 million particles or more, the visualization of large fields-of-view usually suffers from strong aliasing artifacts, because the mismatch between data size and output resolution leads to severe under-sampling of the geometry. Excessive super-sampling can alleviate this problem, but is prohibitively expensive. This paper presents a novel visualization method for large-scale particle data that addresses aliasing while enabling interactive high-quality rendering. We introduce the novel concept of screen-space normal distribution functions (S-NDFs) for particle data. S-NDFs represent the distribution of surface normals that map to a given pixel in screen space, which enables high-quality re-lighting without re-rendering particles. In order to facilitate interactive zooming, we cache S-NDFs in a screen-space mipmap (S-MIP). Together, these two concepts enable interactive, scale-consistent re-lighting and shading changes, as well as zooming, without having to re-sample the particle data. We show how our method facilitates the interactive exploration of real-world large-scale MD simulation data in different scenarios.

An evaluation of systematic tuberculosis screening at private facilities in Karachi, Pakistan.

Directory of Open Access Journals (Sweden)

Jacob Creswell

Full Text Available BACKGROUND: In Pakistan, like many Asian countries, a large proportion of healthcare is provided through the private sector. We evaluated a systematic screening strategy to identify people with tuberculosis in private facilities in Karachi and assessed the approaches' ability to diagnose patients earlier in their disease progression. METHODS AND FINDINGS: Lay workers at 89 private clinics and a large hospital outpatient department screened all attendees for tuberculosis using a mobile phone-based questionnaire during one year. The number needed to screen to detect a case of tuberculosis was calculated. To evaluate early diagnosis, we tested for differences in cough duration and smear grading by screening facility. 529,447 people were screened, 1,010 smear-positive tuberculosis cases were detected and 942 (93.3% started treatment, representing 58.7% of all smear-positive cases notified in the intervention area. The number needed to screen to detect a smear-positive case was 124 (prevalence 806/100,000 at the hospital and 763 (prevalence 131/100,000 at the clinics; however, ten times the number of individuals were screened in clinics. People with smear-positive TB detected at the hospital were less likely to report cough lasting 2-3 weeks (RR 0.66 95%CI [0.49-0.90] and more likely to report cough duration >3 weeks (RR 1.10 95%CI [1.03-1.18]. Smear-positive cases at the clinics were less likely to have a +3 grade (RR 0.76 95%CI [0.63-0.92] and more likely to have +1 smear grade (RR 1.24 95%CI [1.02-1.51]. CONCLUSIONS: Tuberculosis screening at private facilities is acceptable and can yield large numbers of previously undiagnosed cases. Screening at general practitioner clinics may find cases earlier than at hospitals although more people must be screened to identify a case of tuberculosis. Limitations include lack of culture testing, therefore underestimating true TB prevalence. Using more sensitive and specific screening and diagnostic tests such

An evaluation of systematic tuberculosis screening at private facilities in Karachi, Pakistan.

Science.gov (United States)

Creswell, Jacob; Khowaja, Saira; Codlin, Andrew; Hashmi, Rabia; Rasheed, Erum; Khan, Mubashir; Durab, Irfan; Mergenthaler, Christina; Hussain, Owais; Khan, Faisal; Khan, Aamir J

2014-01-01

In Pakistan, like many Asian countries, a large proportion of healthcare is provided through the private sector. We evaluated a systematic screening strategy to identify people with tuberculosis in private facilities in Karachi and assessed the approaches' ability to diagnose patients earlier in their disease progression. Lay workers at 89 private clinics and a large hospital outpatient department screened all attendees for tuberculosis using a mobile phone-based questionnaire during one year. The number needed to screen to detect a case of tuberculosis was calculated. To evaluate early diagnosis, we tested for differences in cough duration and smear grading by screening facility. 529,447 people were screened, 1,010 smear-positive tuberculosis cases were detected and 942 (93.3%) started treatment, representing 58.7% of all smear-positive cases notified in the intervention area. The number needed to screen to detect a smear-positive case was 124 (prevalence 806/100,000) at the hospital and 763 (prevalence 131/100,000) at the clinics; however, ten times the number of individuals were screened in clinics. People with smear-positive TB detected at the hospital were less likely to report cough lasting 2-3 weeks (RR 0.66 95%CI [0.49-0.90]) and more likely to report cough duration >3 weeks (RR 1.10 95%CI [1.03-1.18]). Smear-positive cases at the clinics were less likely to have a +3 grade (RR 0.76 95%CI [0.63-0.92]) and more likely to have +1 smear grade (RR 1.24 95%CI [1.02-1.51]). Tuberculosis screening at private facilities is acceptable and can yield large numbers of previously undiagnosed cases. Screening at general practitioner clinics may find cases earlier than at hospitals although more people must be screened to identify a case of tuberculosis. Limitations include lack of culture testing, therefore underestimating true TB prevalence. Using more sensitive and specific screening and diagnostic tests such as chest x-ray and Xpert MTB/RIF may improve results.

Lovelock inflation and the number of large dimensions

CERN Document Server

Ferrer, Francesc

2007-01-01

We discuss an inflationary scenario based on Lovelock terms. These higher order curvature terms can lead to inflation when there are more than three spatial dimensions. Inflation will end if the extra dimensions are stabilised, so that at most three dimensions are free to expand. This relates graceful exit to the number of large dimensions.

Hepatitis C screening trends in a large integrated health system.

Science.gov (United States)

Linas, Benjamin P; Hu, Haihong; Barter, Devra M; Horberg, Michael

2014-05-01

As new hepatitis C virus (HCV) therapies emerge, only 1%-12% of individuals are screened in the US for HCV infection. Presently, HCV screening trends are unknown. We utilized the Kaiser Permanente Mid-Atlantic States' (KPMAS) data repository to investigate HCV antibody screening between January 1, 2003 and December 31, 2012. We identified the proportion screened for HCV and 5-year cumulative incidence of screening, the screening positivity rate, the provider types performing HCV screening, patient-level factors associated with being screened, and trends in screening over time. There were 444,594 patients who met the inclusion criteria. Overall, 15.8% of the cohort was ever screened for HCV. Adult primary care and obstetrics and gynecology providers performed 75.9% of all screening. The overall test positivity rate was 3.8%. Screening was more frequent in younger age groups (P <.0001) and those with a documented history of illicit drug use (P <.0001). Patients with missing drug use history (46.7%) were least likely to be screened (P <.0001). While the rate of HCV screening increased in the later years of the study among those enrolled in KPMAS 2009-2012, only 11.8% were screened by the end of follow-up. Screening for HCV is increasing but remains incomplete. Targeting screening to those with a history of injection drug will not likely expand screening, as nearly half of patients have no documented drug use history. Routine screening is likely the most effective approach to expand HCV screening. Copyright © 2014. Published by Elsevier Inc.

Bivariate pointing movements on large touch screens: investigating the validity of a refined Fitts' Law.

Science.gov (United States)

Bützler, Jennifer; Vetter, Sebastian; Jochems, Nicole; Schlick, Christopher M

2012-01-01

On the basis of three empirical studies Fitts' Law was refined for bivariate pointing tasks on large touch screens. In the first study different target width parameters were investigated. The second study considered the effect of the motion angle. Based on the results of the two studies a refined model for movement time in human-computer interaction was formulated. A third study, which is described here in detail, concerns the validation of the refined model. For the validation study 20 subjects had to execute a bivariate pointing task on a large touch screen. In the experimental task 250 rectangular target objects were displayed at a randomly chosen position on the screen covering a broad range of ID values (ID= [1.01; 4.88]). Compared to existing refinements of Fitts' Law, the new model shows highest predictive validity. A promising field of application of the model is the ergonomic design and evaluation of project management software. By using the refined model, software designers can calculate a priori the appropriate angular position and the size of buttons, menus or icons.

Mechanistic modeling for mammography screening risks

International Nuclear Information System (INIS)

Bijwaard, Harmen

2008-01-01

Full text: Western populations show a very high incidence of breast cancer and in many countries mammography screening programs have been set up for the early detection of these cancers. Through these programs large numbers of women (in the Netherlands, 700.000 per year) are exposed to low but not insignificant X-ray doses. ICRP based risk estimates indicate that the number of breast cancer casualties due to mammography screening can be as high as 50 in the Netherlands per year. The number of lives saved is estimated to be much higher, but for an accurate calculation of the benefits of screening a better estimate of these risks is indispensable. Here it is attempted to better quantify the radiological risks of mammography screening through the application of a biologically based model for breast tumor induction by X-rays. The model is applied to data obtained from the National Institutes of Health in the U.S. These concern epidemiological data of female TB patients who received high X-ray breast doses in the period 1930-1950 through frequent fluoroscopy of their lungs. The mechanistic model that is used to describe the increased breast cancer incidence is based on an earlier study by Moolgavkar et al. (1980), in which the natural background incidence of breast cancer was modeled. The model allows for a more sophisticated extrapolation of risks to the low dose X-ray exposures that are common in mammography screening and to the higher ages that are usually involved. Furthermore, it allows for risk transfer to other (non-western) populations. The results have implications for decisions on the frequency of screening, the number of mammograms taken at each screening, minimum and maximum ages for screening and the transfer to digital equipment. (author)

Cognitive-behavioral screening reveals prevalent impairment in a large multicenter ALS cohort.

Science.gov (United States)

Murphy, Jennifer; Factor-Litvak, Pam; Goetz, Raymond; Lomen-Hoerth, Catherine; Nagy, Peter L; Hupf, Jonathan; Singleton, Jessica; Woolley, Susan; Andrews, Howard; Heitzman, Daragh; Bedlack, Richard S; Katz, Jonathan S; Barohn, Richard J; Sorenson, Eric J; Oskarsson, Björn; Fernandes Filho, J Americo M; Kasarskis, Edward J; Mozaffar, Tahseen; Rollins, Yvonne D; Nations, Sharon P; Swenson, Andrea J; Koczon-Jaremko, Boguslawa A; Mitsumoto, Hiroshi

2016-03-01

To characterize the prevalence of cognitive and behavioral symptoms using a cognitive/behavioral screening battery in a large prospective multicenter study of amyotrophic lateral sclerosis (ALS). Two hundred seventy-four patients with ALS completed 2 validated cognitive screening tests and 2 validated behavioral interviews with accompanying caregivers. We examined the associations between cognitive and behavioral performance, demographic and clinical data, and C9orf72 mutation data. Based on the ALS Cognitive Behavioral Screen cognitive score, 6.5% of the sample scored below the cutoff score for frontotemporal lobar dementia, 54.2% scored in a range consistent with ALS with mild cognitive impairment, and 39.2% scored in the normal range. The ALS Cognitive Behavioral Screen behavioral subscale identified 16.5% of the sample scoring below the dementia cutoff score, with an additional 14.1% scoring in the ALS behavioral impairment range, and 69.4% scoring in the normal range. This investigation revealed high levels of cognitive and behavioral impairment in patients with ALS within 18 months of symptom onset, comparable to prior investigations. This investigation illustrates the successful use and scientific value of adding a cognitive-behavioral screening tool in studies of motor neuron diseases, to provide neurologists with an efficient method to measure these common deficits and to understand how they relate to key clinical variables, when extensive neuropsychological examinations are unavailable. These tools, developed specifically for patients with motor impairment, may be particularly useful in patient populations with multiple sclerosis and Parkinson disease, who are known to have comorbid cognitive decline. © 2016 American Academy of Neurology.

Screening of recombinant inbred lines for salinity tolerance in bread ...

African Journals Online (AJOL)

Screening a large number of plants for salinity tolerance is not easy, therefore this investigation was performed to evaluate and screen 186 F8 recombinant inbred lines (RILs) derived from a cross between Superhead#2 (Super Seri) and Roshan wheat varieties for salinity tolerance. All the individuals were evaluated under ...

Positive predictive value estimates for cell-free noninvasive prenatal screening from data of a large referral genetic diagnostic laboratory.

Science.gov (United States)

Petersen, Andrea K; Cheung, Sau Wai; Smith, Janice L; Bi, Weimin; Ward, Patricia A; Peacock, Sandra; Braxton, Alicia; Van Den Veyver, Ignatia B; Breman, Amy M

2017-12-01

Since its debut in 2011, cell-free fetal DNA screening has undergone rapid expansion with respect to both utilization and coverage. However, conclusive data regarding the clinical validity and utility of this screening tool, both for the originally included common autosomal and sex-chromosomal aneuploidies as well as the more recently added chromosomal microdeletion syndromes, have lagged behind. Thus, there is a continued need to educate clinicians and patients about the current benefits and limitations of this screening tool to inform pre- and posttest counseling, pre/perinatal decision making, and medical risk assessment/management. The objective of this study was to determine the positive predictive value and false-positive rates for different chromosomal abnormalities identified by cell-free fetal DNA screening using a large data set of diagnostic testing results on invasive samples submitted to the laboratory for confirmatory studies. We tested 712 patient samples sent to our laboratory to confirm a cell-free fetal DNA screening result, indicating high risk for a chromosome abnormality. We compiled data from all cases in which the indication for confirmatory testing was a positive cell-free fetal DNA screen, including the common trisomies, sex chromosomal aneuploidies, microdeletion syndromes, and other large genome-wide copy number abnormalities. Testing modalities included fluorescence in situ hybridization, G-banded karyotype, and/or chromosomal microarray analysis performed on chorionic villus samples, amniotic fluid, or postnatally obtained blood samples. Positive predictive values and false-positive rates were calculated from tabulated data. The positive predictive values for trisomy 13, 18, and 21 were consistent with previous reports at 45%, 76%, and 84%, respectively. For the microdeletion syndrome regions, positive predictive values ranged from 0% for detection of Cri-du-Chat syndrome and Prader-Willi/Angelman syndrome to 14% for 1p36 deletion

[Dual process in large number estimation under uncertainty].

Science.gov (United States)

Matsumuro, Miki; Miwa, Kazuhisa; Terai, Hitoshi; Yamada, Kento

2016-08-01

According to dual process theory, there are two systems in the mind: an intuitive and automatic System 1 and a logical and effortful System 2. While many previous studies about number estimation have focused on simple heuristics and automatic processes, the deliberative System 2 process has not been sufficiently studied. This study focused on the System 2 process for large number estimation. First, we described an estimation process based on participants’ verbal reports. The task, corresponding to the problem-solving process, consisted of creating subgoals, retrieving values, and applying operations. Second, we investigated the influence of such deliberative process by System 2 on intuitive estimation by System 1, using anchoring effects. The results of the experiment showed that the System 2 process could mitigate anchoring effects.

Automated recycling of chemistry for virtual screening and library design.

Science.gov (United States)

Vainio, Mikko J; Kogej, Thierry; Raubacher, Florian

2012-07-23

An early stage drug discovery project needs to identify a number of chemically diverse and attractive compounds. These hit compounds are typically found through high-throughput screening campaigns. The diversity of the chemical libraries used in screening is therefore important. In this study, we describe a virtual high-throughput screening system called Virtual Library. The system automatically "recycles" validated synthetic protocols and available starting materials to generate a large number of virtual compound libraries, and allows for fast searches in the generated libraries using a 2D fingerprint based screening method. Virtual Library links the returned virtual hit compounds back to experimental protocols to quickly assess the synthetic accessibility of the hits. The system can be used as an idea generator for library design to enrich the screening collection and to explore the structure-activity landscape around a specific active compound.

On Independence for Capacities with Law of Large Numbers

OpenAIRE

Huang, Weihuan

2017-01-01

This paper introduces new notions of Fubini independence and Exponential independence of random variables under capacities to fit Ellsberg's model, and finds out the relationships between Fubini independence, Exponential independence, MacCheroni and Marinacci's independence and Peng's independence. As an application, we give a weak law of large numbers for capacities under Exponential independence.

Automatic trajectory measurement of large numbers of crowded objects

Science.gov (United States)

Li, Hui; Liu, Ye; Chen, Yan Qiu

2013-06-01

Complex motion patterns of natural systems, such as fish schools, bird flocks, and cell groups, have attracted great attention from scientists for years. Trajectory measurement of individuals is vital for quantitative and high-throughput study of their collective behaviors. However, such data are rare mainly due to the challenges of detection and tracking of large numbers of objects with similar visual features and frequent occlusions. We present an automatic and effective framework to measure trajectories of large numbers of crowded oval-shaped objects, such as fish and cells. We first use a novel dual ellipse locator to detect the coarse position of each individual and then propose a variance minimization active contour method to obtain the optimal segmentation results. For tracking, cost matrix of assignment between consecutive frames is trainable via a random forest classifier with many spatial, texture, and shape features. The optimal trajectories are found for the whole image sequence by solving two linear assignment problems. We evaluate the proposed method on many challenging data sets.

Large-Area Cross-Aligned Silver Nanowire Electrodes for Flexible, Transparent, and Force-Sensitive Mechanochromic Touch Screens.

Science.gov (United States)

Cho, Seungse; Kang, Saewon; Pandya, Ashish; Shanker, Ravi; Khan, Ziyauddin; Lee, Youngsu; Park, Jonghwa; Craig, Stephen L; Ko, Hyunhyub

2017-04-25

Silver nanowire (AgNW) networks are considered to be promising structures for use as flexible transparent electrodes for various optoelectronic devices. One important application of AgNW transparent electrodes is the flexible touch screens. However, the performances of flexible touch screens are still limited by the large surface roughness and low electrical to optical conductivity ratio of random network AgNW electrodes. In addition, although the perception of writing force on the touch screen enables a variety of different functions, the current technology still relies on the complicated capacitive force touch sensors. This paper demonstrates a simple and high-throughput bar-coating assembly technique for the fabrication of large-area (>20 × 20 cm 2 ), highly cross-aligned AgNW networks for transparent electrodes with the sheet resistance of 21.0 Ω sq -1 at 95.0% of optical transmittance, which compares favorably with that of random AgNW networks (sheet resistance of 21.0 Ω sq -1 at 90.4% of optical transmittance). As a proof of concept demonstration, we fabricate flexible, transparent, and force-sensitive touch screens using cross-aligned AgNW electrodes integrated with mechanochromic spiropyran-polydimethylsiloxane composite film. Our force-sensitive touch screens enable the precise monitoring of dynamic writings, tracing and drawing of underneath pictures, and perception of handwriting patterns with locally different writing forces. The suggested technique provides a robust and powerful platform for the controllable assembly of nanowires beyond the scale of conventional fabrication techniques, which can find diverse applications in multifunctional flexible electronic and optoelectronic devices.

Screening and large-scale expression of membrane proteins in mammalian cells for structural studies.

Science.gov (United States)

Goehring, April; Lee, Chia-Hsueh; Wang, Kevin H; Michel, Jennifer Carlisle; Claxton, Derek P; Baconguis, Isabelle; Althoff, Thorsten; Fischer, Suzanne; Garcia, K Christopher; Gouaux, Eric

2014-11-01

Structural, biochemical and biophysical studies of eukaryotic membrane proteins are often hampered by difficulties in overexpression of the candidate molecule. Baculovirus transduction of mammalian cells (BacMam), although a powerful method to heterologously express membrane proteins, can be cumbersome for screening and expression of multiple constructs. We therefore developed plasmid Eric Gouaux (pEG) BacMam, a vector optimized for use in screening assays, as well as for efficient production of baculovirus and robust expression of the target protein. In this protocol, we show how to use small-scale transient transfection and fluorescence-detection size-exclusion chromatography (FSEC) experiments using a GFP-His8-tagged candidate protein to screen for monodispersity and expression level. Once promising candidates are identified, we describe how to generate baculovirus, transduce HEK293S GnTI(-) (N-acetylglucosaminyltransferase I-negative) cells in suspension culture and overexpress the candidate protein. We have used these methods to prepare pure samples of chicken acid-sensing ion channel 1a (cASIC1) and Caenorhabditis elegans glutamate-gated chloride channel (GluCl) for X-ray crystallography, demonstrating how to rapidly and efficiently screen hundreds of constructs and accomplish large-scale expression in 4-6 weeks.

A full picture of large lepton number asymmetries of the Universe

Energy Technology Data Exchange (ETDEWEB)

Barenboim, Gabriela [Departament de Física Teòrica and IFIC, Universitat de València-CSIC, C/ Dr. Moliner, 50, Burjassot, E-46100 Spain (Spain); Park, Wan-Il, E-mail: Gabriela.Barenboim@uv.es, E-mail: wipark@jbnu.ac.kr [Department of Science Education (Physics), Chonbuk National University, 567 Baekje-daero, Jeonju, 561-756 (Korea, Republic of)

2017-04-01

A large lepton number asymmetry of O(0.1−1) at present Universe might not only be allowed but also necessary for consistency among cosmological data. We show that, if a sizeable lepton number asymmetry were produced before the electroweak phase transition, the requirement for not producing too much baryon number asymmetry through sphalerons processes, forces the high scale lepton number asymmetry to be larger than about 03. Therefore a mild entropy release causing O(10-100) suppression of pre-existing particle density should take place, when the background temperature of the Universe is around T = O(10{sup −2}-10{sup 2}) GeV for a large but experimentally consistent asymmetry to be present today. We also show that such a mild entropy production can be obtained by the late-time decays of the saxion, constraining the parameters of the Peccei-Quinn sector such as the mass and the vacuum expectation value of the saxion field to be m {sub φ} ∼> O(10) TeV and φ{sub 0} ∼> O(10{sup 14}) GeV, respectively.

Evidence for Knowledge of the Syntax of Large Numbers in Preschoolers

Science.gov (United States)

Barrouillet, Pierre; Thevenot, Catherine; Fayol, Michel

2010-01-01

The aim of this study was to provide evidence for knowledge of the syntax governing the verbal form of large numbers in preschoolers long before they are able to count up to these numbers. We reasoned that if such knowledge exists, it should facilitate the maintenance in short-term memory of lists of lexical primitives that constitute a number…

Mathematical Models of the Sinusoidal Screen Family

Directory of Open Access Journals (Sweden)

Tajana Koren

2011-06-01

Full Text Available In this paper we will define a family of sinusoidal screening elements and explore the possibilities of their application in graphic arts, securities printing and design solutions in photography and typography editing. For this purpose mathematical expressions of sinusoidal families were converted into a Postscript language. The introduction of a random variable results in a countless number of various mutations which cannot be repeated without knowing the programming code itself. The use of the family of screens in protection of securities is thus of great importance. Other possible application of modulated sinusoidal screens is related to the large format color printing. This paper will test the application of sinusoidal screens in vector graphics, pixel graphics and typography. The development of parameters in the sinusoidal screen element algorithms gives new forms defined within screening cells with strict requirements of coverage implementation. Individual solutions include stochastic algorithms, as well as the autonomy of screening forms in regard to multicolor printing channels.

Production of large-area polymer solar cells by industrial silk screen printing, lifetime considerations and lamination with polyethyleneterephthalate

DEFF Research Database (Denmark)

Krebs, Frederik C; Alstrup, J.; Spanggaard, H.

2004-01-01

The possibility of making large area (100 cm(2)) polymer solar cells based on the conjugated polymer poly 1,4-(2-methoxy-5-ethylhexyloxy)phenylenevinylene (MEH-PPV) was demonstrated. Devices were prepared by etching an electrode pattern on ITO covered polyethyleneterephthalate (PET) substrates....... A pattern of conducting silver epoxy allowing for electrical contacts to the device was silk screen printed and hardened. Subsequently a pattern of MEH-PPV was silk screen printed in registry with the ITO electrode pattern on top of the substrate. Final evaporation of an aluminum electrode or sublimation......). The half-life based on I-sc in air for the devices were 63 h. The cells were laminated in a 125 mum PET encasement. Lamination had a negative effect on the lifetime. We demonstrate the feasibility of industrial production of large area solar cells (1 m(2)) by silk screen printing and envisage...

Similarities between 2D and 3D convection for large Prandtl number

Indian Academy of Sciences (India)

2016-06-18

RBC), we perform a compara- tive study of the spectra and fluxes of energy and entropy, and the scaling of large-scale quantities for large and infinite Prandtl numbers in two (2D) and three (3D) dimensions. We observe close ...

Comparative performance of modern digital mammography systems in a large breast screening program

Energy Technology Data Exchange (ETDEWEB)

Yaffe, Martin J., E-mail: martin.yaffe@sri.utoronto.ca; Bloomquist, Aili K.; Hunter, David M.; Mawdsley, Gordon E. [Physical Sciences Division, Sunnybrook Research Institute, Departments of Medical Biophysics and Medical Imaging, University of Toronto, Ontario M4N 3M5 (Canada); Chiarelli, Anna M. [Prevention and Cancer Control, Cancer Care Ontario, Dalla Lana School of Public Health, University of Toronto, Ontario M4N 3M5, Canada and Ontario Breast Screening Program, Cancer Care Ontario, Toronto, Ontario M5G 1X3 (Canada); Muradali, Derek [Ontario Breast Screening Program, Cancer Care Ontario, Toronto, Ontario M5G 1X3 (Canada); Mainprize, James G. [Physical Sciences Division, Sunnybrook Research Institute, Toronto, Ontario M4N 3M5 (Canada)

2013-12-15

Purpose: To compare physical measures pertaining to image quality among digital mammography systems utilized in a large breast screening program. To examine qualitatively differences in these measures and differences in clinical cancer detection rates between CR and DR among sites within that program. Methods: As part of the routine quality assurance program for screening, field measurements are made of several variables considered to correlate with the diagnostic quality of medical images including: modulation transfer function, noise equivalent quanta, d′ (an index of lesion detectability) and air kerma to allow estimation of mean glandular dose. In addition, images of the mammography accreditation phantom are evaluated. Results: It was found that overall there were marked differences between the performance measures of DR and CR mammography systems. In particular, the modulation transfer functions obtained with the DR systems were found to be higher, even for larger detector element sizes. Similarly, the noise equivalent quanta, d′, and the phantom scores were higher, while the failure rates associated with low signal-to-noise ratio and high dose were lower with DR. These results were consistent with previous findings in the authors’ program that the breast cancer detection rates at sites employing CR technology were, on average, 30.6% lower than those that used DR mammography. Conclusions: While the clinical study was not large enough to allow a statistically powered system-by-system assessment of cancer detection accuracy, the physical measures expressing spatial resolution, and signal-to-noise ratio are consistent with the published finding that sites employing CR systems had lower cancer detection rates than those using DR systems for screening mammography.

The three-large-primes variant of the number field sieve

NARCIS (Netherlands)

S.H. Cavallar

2002-01-01

textabstractThe Number Field Sieve (NFS) is the asymptotically fastest known factoringalgorithm for large integers.This method was proposed by John Pollard in 1988. Sincethen several variants have been implemented with the objective of improving thesiever which is the most time consuming part of

Fully Screen-Printed, Large-Area, and Flexible Active-Matrix Electrochromic Displays Using Carbon Nanotube Thin-Film Transistors.

Science.gov (United States)

Cao, Xuan; Lau, Christian; Liu, Yihang; Wu, Fanqi; Gui, Hui; Liu, Qingzhou; Ma, Yuqiang; Wan, Haochuan; Amer, Moh R; Zhou, Chongwu

2016-11-22

Semiconducting single-wall carbon nanotubes are ideal semiconductors for printed electronics due to their advantageous electrical and mechanical properties, intrinsic printability in solution, and desirable stability in air. However, fully printed, large-area, high-performance, and flexible carbon nanotube active-matrix backplanes are still difficult to realize for future displays and sensing applications. Here, we report fully screen-printed active-matrix electrochromic displays employing carbon nanotube thin-film transistors. Our fully printed backplane shows high electrical performance with mobility of 3.92 ± 1.08 cm 2 V -1 s -1 , on-off current ratio I on /I off ∼ 10 4 , and good uniformity. The printed backplane was then monolithically integrated with an array of printed electrochromic pixels, resulting in an entirely screen-printed active-matrix electrochromic display (AMECD) with good switching characteristics, facile manufacturing, and long-term stability. Overall, our fully screen-printed AMECD is promising for the mass production of large-area and low-cost flexible displays for applications such as disposable tags, medical electronics, and smart home appliances.

Secret Sharing Schemes with a large number of players from Toric Varieties

DEFF Research Database (Denmark)

Hansen, Johan P.

A general theory for constructing linear secret sharing schemes over a finite field $\\Fq$ from toric varieties is introduced. The number of players can be as large as $(q-1)^r-1$ for $r\\geq 1$. We present general methods for obtaining the reconstruction and privacy thresholds as well as conditions...... for multiplication on the associated secret sharing schemes. In particular we apply the method on certain toric surfaces. The main results are ideal linear secret sharing schemes where the number of players can be as large as $(q-1)^2-1$. We determine bounds for the reconstruction and privacy thresholds...

Suspect screening of large numbers of emerging contaminants in environmental waters using artificial neural networks for chromatographic retention time prediction and high resolution mass spectrometry data analysis.

Science.gov (United States)

Bade, Richard; Bijlsma, Lubertus; Miller, Thomas H; Barron, Leon P; Sancho, Juan Vicente; Hernández, Felix

2015-12-15

The recent development of broad-scope high resolution mass spectrometry (HRMS) screening methods has resulted in a much improved capability for new compound identification in environmental samples. However, positive identifications at the ng/L concentration level rely on analytical reference standards for chromatographic retention time (tR) and mass spectral comparisons. Chromatographic tR prediction can play a role in increasing confidence in suspect screening efforts for new compounds in the environment, especially when standards are not available, but reliable methods are lacking. The current work focuses on the development of artificial neural networks (ANNs) for tR prediction in gradient reversed-phase liquid chromatography and applied along with HRMS data to suspect screening of wastewater and environmental surface water samples. Based on a compound tR dataset of >500 compounds, an optimized 4-layer back-propagation multi-layer perceptron model enabled predictions for 85% of all compounds to within 2min of their measured tR for training (n=344) and verification (n=100) datasets. To evaluate the ANN ability for generalization to new data, the model was further tested using 100 randomly selected compounds and revealed 95% prediction accuracy within the 2-minute elution interval. Given the increasing concern on the presence of drug metabolites and other transformation products (TPs) in the aquatic environment, the model was applied along with HRMS data for preliminary identification of pharmaceutically-related compounds in real samples. Examples of compounds where reference standards were subsequently acquired and later confirmed are also presented. To our knowledge, this work presents for the first time, the successful application of an accurate retention time predictor and HRMS data-mining using the largest number of compounds to preliminarily identify new or emerging contaminants in wastewater and surface waters. Copyright © 2015 Elsevier B.V. All rights

Quasi-isodynamic configuration with large number of periods

International Nuclear Information System (INIS)

Shafranov, V.D.; Isaev, M.Yu.; Mikhailov, M.I.; Subbotin, A.A.; Cooper, W.A.; Kalyuzhnyj, V.N.; Kasilov, S.V.; Nemov, V.V.; Kernbichler, W.; Nuehrenberg, C.; Nuehrenberg, J.; Zille, R.

2005-01-01

It has been previously reported that quasi-isodynamic (qi) stellarators with poloidal direction of the contours of B on magnetic surface can exhibit very good fast- particle collisionless confinement. In addition, approaching the quasi-isodynamicity condition leads to diminished neoclassical transport and small bootstrap current. The calculations of local-mode stability show that there is a tendency toward an increasing beta limit with increasing number of periods. The consideration of the quasi-helically symmetric systems has demonstrated that with increasing aspect ratio (and number of periods) the optimized configuration approaches the straight symmetric counterpart, for which the optimal parameters and highest beta values were found by optimization of the boundary magnetic surface cross-section. The qi system considered here with zero net toroidal current do not have a symmetric analogue in the limit of large aspect ratio and finite rotational transform. Thus, it is not clear whether some invariant structure of the configuration period exists in the limit of negligible toroidal effect and what are the best possible parameters for it. In the present paper the results of an optimization of the configuration with N = 12 number of periods are presented. Such properties as fast-particle confinement, effective ripple, structural factor of bootstrap current and MHD stability are considered. It is shown that MHD stability limit here is larger than in configurations with smaller number of periods considered earlier. Nevertheless, the toroidal effect in this configuration is still significant so that a simple increase of the number of periods and proportional growth of aspect ratio do not conserve favourable neoclassical transport and ideal local-mode stability properties. (author)

Chemically intuited, large-scale screening of MOFs by machine learning techniques

Science.gov (United States)

Borboudakis, Giorgos; Stergiannakos, Taxiarchis; Frysali, Maria; Klontzas, Emmanuel; Tsamardinos, Ioannis; Froudakis, George E.

2017-10-01

A novel computational methodology for large-scale screening of MOFs is applied to gas storage with the use of machine learning technologies. This approach is a promising trade-off between the accuracy of ab initio methods and the speed of classical approaches, strategically combined with chemical intuition. The results demonstrate that the chemical properties of MOFs are indeed predictable (stochastically, not deterministically) using machine learning methods and automated analysis protocols, with the accuracy of predictions increasing with sample size. Our initial results indicate that this methodology is promising to apply not only to gas storage in MOFs but in many other material science projects.

Automated Groundwater Screening

International Nuclear Information System (INIS)

Taylor, Glenn A.; Collard, Leonard B.

2005-01-01

The Automated Intruder Analysis has been extended to include an Automated Ground Water Screening option. This option screens 825 radionuclides while rigorously applying the National Council on Radiation Protection (NCRP) methodology. An extension to that methodology is presented to give a more realistic screening factor for those radionuclides which have significant daughters. The extension has the promise of reducing the number of radionuclides which must be tracked by the customer. By combining the Automated Intruder Analysis with the Automated Groundwater Screening a consistent set of assumptions and databases is used. A method is proposed to eliminate trigger values by performing rigorous calculation of the screening factor thereby reducing the number of radionuclides sent to further analysis. Using the same problem definitions as in previous groundwater screenings, the automated groundwater screening found one additional nuclide, Ge-68, which failed the screening. It also found that 18 of the 57 radionuclides contained in NCRP Table 3.1 failed the screening. This report describes the automated groundwater screening computer application

Current State of and Needs for Hepatitis B Screening: Results of a Large Screening Study in a Low-Prevalent, Metropolitan Region

Science.gov (United States)

Bottero, Julie; Boyd, Anders; Lemoine, Maud; Carrat, Fabrice; Gozlan, Joel; Collignon, Anne; Boo, Nicolas; Dhotte, Philippe; Varsat, Brigitte; Muller, Gerard; Cha, Olivier; Valin, Nadia; Nau, Jean; Campa, Pauline; Silbermann, Benjamin; Bary, Marc; Girard, Pierre-Marie; Lacombe, Karine

2014-01-01

Background In low hepatitis B virus (HBV)-prevalent countries, most HBV-infected persons are unaware of their status. We aimed to evaluate whether (i) previous HBV-testing, (ii) physicians decision to screen, and (iii) CDC's recommendations identified infected individuals and which risk-factor groups needing testing. Methods During a mass, multi-center HBV-screening study from September 2010-August 2011, 3929 participants were screened for hepatitis B surface antigen (HBsAg), anti-HBs and anti-Hepatitis B core antibodies (anti-HBcAb). Questions on HBV risk-factors and testing practices were asked to participants, while participants' eligibility for HBV-testing was asked to study medical professionals. Results 85 (2.2%) participants were HBsAg-positive, while 659 (16.8%) had either resolved HBV infection or isolated anti-HBcAb. When comparing practices, HBV-testing was more likely to occur in HBV-infected participants if Centers for Disease Control and Prevention (CDC) recommendations were used (Sensitivity = 100%, 95%CI: 95.8–100) than physicians' discretion (Sensitivity = 87.1%, 95%CI: 78.0–93.4) or previous HBV-test (Sensitivity = 36.5%, 95%CI: 26.3–47.6) (p<0.0001). Nevertheless, many non-infected individuals would still have been screened using CDC-recommendations (Specificity = 31.1%, 95%CI: 29.6–32.6). Using multivariable logistic regression, HBsAg-positive status was significantly associated with the following: males, originating from high HBV-endemic region, contact with HBV-infected individual, without national healthcare, and intravenous-drug user (IDU). Of these risk-factors, physician's discretion for testing HBV was not significantly associated with participants' geographical origin or IDU. Conclusions Missed opportunities of HBV-screening are largely due to underestimating country of origin as a risk-factor. Applying CDC-recommendations could improve HBV-screening, but with the disadvantage of many tests. Further development of

Time Domain View of Liquid-like Screening and Large Polaron Formation in Lead Halide Perovskites

Science.gov (United States)

Joshi, Prakriti Pradhan; Miyata, Kiyoshi; Trinh, M. Tuan; Zhu, Xiaoyang

The structural softness and dynamic disorder of lead halide perovskites contributes to their remarkable optoelectronic properties through efficient charge screening and large polaron formation. Here we provide a direct time-domain view of the liquid-like structural dynamics and polaron formation in single crystal CH3NH3PbBr3 and CsPbBr3 using femtosecond optical Kerr effect spectroscopy in conjunction with transient reflectance spectroscopy. We investigate structural dynamics as function of pump energy, which enables us to examine the dynamics in the absence and presence of charge carriers. In the absence of charge carriers, structural dynamics are dominated by over-damped picosecond motions of the inorganic PbBr3- sub-lattice and these motions are strongly coupled to band-gap electronic transitions. Carrier injection from across-gap optical excitation triggers additional 0.26 ps dynamics in CH3NH3PbBr3 that can be attributed to the formation of large polarons. In comparison, large polaron formation is slower in CsPbBr3 with a time constant of 0.6 ps. We discuss how such dynamic screening protects charge carriers in lead halide perovskites. US Department of Energy, Office of Science - Basic Energy Sciences.

Approaches to virtual screening and screening library selection.

Science.gov (United States)

Wildman, Scott A

2013-01-01

The ease of access to virtual screening (VS) software in recent years has resulted in a large increase in literature reports. Over 300 publications in the last year report the use of virtual screening techniques to identify new chemical matter or present the development of new virtual screening techniques. The increased use is accompanied by a corresponding increase in misuse and misinterpretation of virtual screening results. This review aims to identify many of the common difficulties associated with virtual screening and allow researchers to better assess the reliability of their virtual screening effort.

E-commerce between a large firm and a SME supplier: a screening model

OpenAIRE

Veronica, Alderete Maria

2009-01-01

This paper derives a model of screening contracts in the presence of positive network effects when building an electronic commerce network (e-commerce) between a large firm and a small and medium sized enterprise (SME) supplier based on Compte (2008). Compte (2008) main insight is that when several potential candidates compete for the task, the principal will in general improve the performance of his firm by inducing the member candidates to assess their competence before signing the contract...

Can interface features affect aggression resulting from violent video game play? An examination of realistic controller and large screen size.

Science.gov (United States)

Kim, Ki Joon; Sundar, S Shyam

2013-05-01

Aggressiveness attributed to violent video game play is typically studied as a function of the content features of the game. However, can interface features of the game also affect aggression? Guided by the General Aggression Model (GAM), we examine the controller type (gun replica vs. mouse) and screen size (large vs. small) as key technological aspects that may affect the state aggression of gamers, with spatial presence and arousal as potential mediators. Results from a between-subjects experiment showed that a realistic controller and a large screen display induced greater aggression, presence, and arousal than a conventional mouse and a small screen display, respectively, and confirmed that trait aggression was a significant predictor of gamers' state aggression. Contrary to GAM, however, arousal showed no effects on aggression; instead, presence emerged as a significant mediator.

Fluid Mechanics of Aquatic Locomotion at Large Reynolds Numbers

OpenAIRE

Govardhan, RN; Arakeri, JH

2011-01-01

Abstract | There exist a huge range of fish species besides other aquatic organisms like squids and salps that locomote in water at large Reynolds numbers, a regime of flow where inertial forces dominate viscous forces. In the present review, we discuss the fluid mechanics governing the locomotion of such organisms. Most fishes propel themselves by periodic undulatory motions of the body and tail, and the typical classification of their swimming modes is based on the fraction of their body...

Hierarchical virtual screening approaches in small molecule drug discovery.

Science.gov (United States)

Kumar, Ashutosh; Zhang, Kam Y J

2015-01-01

Virtual screening has played a significant role in the discovery of small molecule inhibitors of therapeutic targets in last two decades. Various ligand and structure-based virtual screening approaches are employed to identify small molecule ligands for proteins of interest. These approaches are often combined in either hierarchical or parallel manner to take advantage of the strength and avoid the limitations associated with individual methods. Hierarchical combination of ligand and structure-based virtual screening approaches has received noteworthy success in numerous drug discovery campaigns. In hierarchical virtual screening, several filters using ligand and structure-based approaches are sequentially applied to reduce a large screening library to a number small enough for experimental testing. In this review, we focus on different hierarchical virtual screening strategies and their application in the discovery of small molecule modulators of important drug targets. Several virtual screening studies are discussed to demonstrate the successful application of hierarchical virtual screening in small molecule drug discovery. Copyright © 2014 Elsevier Inc. All rights reserved.

Combining large number of weak biomarkers based on AUC.

Science.gov (United States)

Yan, Li; Tian, Lili; Liu, Song

2015-12-20

Combining multiple biomarkers to improve diagnosis and/or prognosis accuracy is a common practice in clinical medicine. Both parametric and non-parametric methods have been developed for finding the optimal linear combination of biomarkers to maximize the area under the receiver operating characteristic curve (AUC), primarily focusing on the setting with a small number of well-defined biomarkers. This problem becomes more challenging when the number of observations is not order of magnitude greater than the number of variables, especially when the involved biomarkers are relatively weak. Such settings are not uncommon in certain applied fields. The first aim of this paper is to empirically evaluate the performance of existing linear combination methods under such settings. The second aim is to propose a new combination method, namely, the pairwise approach, to maximize AUC. Our simulation studies demonstrated that the performance of several existing methods can become unsatisfactory as the number of markers becomes large, while the newly proposed pairwise method performs reasonably well. Furthermore, we apply all the combination methods to real datasets used for the development and validation of MammaPrint. The implication of our study for the design of optimal linear combination methods is discussed. Copyright © 2015 John Wiley & Sons, Ltd.

The impact of new national guidelines on screening for gestational diabetes mellitus.

LENUS (Irish Health Repository)

Ali, F M

2013-02-01

Gestational diabetes mellitus (GDM) has important maternal and fetal implications. In 2010, the Health Service Executive published guidelines on GDM. We examined the impact of the new guidelines in a large maternity unit. In January 2011, the hospital replaced the 100 g Oral Glucose Tolerance Test (OGTT) with the new 75 g OGTT. We compared the first 6 months of 2011 with the first 6 months of 2010. The new guidelines were associated with a 22% increase in women screened from 1375 in 2010 to 1679 in 2011 (p < 0.001). Of the women screened, the number diagnosed with GDM increased from 10.1% (n=139) to 13.2% (n=221) (p<0.001).The combination of increased screening and a more sensitive OGTT resulted in the number of women diagnosed with GDM increasing 59% from 139 to 221 (p = 0.02).This large increase has important resource implications but, if clinical outcomes are improved, there should be a decrease in long-term costs.

The Application Law of Large Numbers That Predicts The Amount of Actual Loss in Insurance of Life

Science.gov (United States)

Tinungki, Georgina Maria

2018-03-01

The law of large numbers is a statistical concept that calculates the average number of events or risks in a sample or population to predict something. The larger the population is calculated, the more accurate predictions. In the field of insurance, the Law of Large Numbers is used to predict the risk of loss or claims of some participants so that the premium can be calculated appropriately. For example there is an average that of every 100 insurance participants, there is one participant who filed an accident claim, then the premium of 100 participants should be able to provide Sum Assured to at least 1 accident claim. The larger the insurance participant is calculated, the more precise the prediction of the calendar and the calculation of the premium. Life insurance, as a tool for risk spread, can only work if a life insurance company is able to bear the same risk in large numbers. Here apply what is called the law of large number. The law of large numbers states that if the amount of exposure to losses increases, then the predicted loss will be closer to the actual loss. The use of the law of large numbers allows the number of losses to be predicted better.

Screening, Aharonov - Bohm effect, and linking number in spin systems

International Nuclear Information System (INIS)

Borisenko, O.; Petrov, K.; Faber, M.

2000-01-01

Screening mechanisms and related effects are studied in a variety of spin systems coupled to an external magnetic field. We use a special order parameter which can distinguish between screening due to the kinetic energy of spin excitations and screening due to the magnetic field. The action of this order parameter is based on an analog of the Aharonov - Bohm (AB) effect. The order parameter may test the realization of discrete symmetries embedded into the group symmetry of the theory via probing a nontrivial discrete charge. As simple examples, we study the Gaussian and Ising models. For the latter, we performed also Monte-Carlo simulations for a constant magnetic field. We then apply our results to spin systems with abelian and nonabelian global symmetries in two dimensions and argue that the order parameter proposed could serve as a tool to detect the Berezinskii - Kosterlitz - Thouless (BKT) phase transition

poolHiTS: A Shifted Transversal Design based pooling strategy for high-throughput drug screening

Directory of Open Access Journals (Sweden)

Woolf Peter J

2008-05-01

Full Text Available Abstract Background A key goal of drug discovery is to increase the throughput of small molecule screens without sacrificing screening accuracy. High-throughput screening (HTS in drug discovery involves testing a large number of compounds in a biological assay to identify active compounds. Normally, molecules from a large compound library are tested individually to identify the activity of each molecule. Usually a small number of compounds are found to be active, however the presence of false positive and negative testing errors suggests that this one-drug one-assay screening strategy can be significantly improved. Pooling designs are testing schemes that test mixtures of compounds in each assay, thereby generating a screen of the whole compound library in fewer tests. By repeatedly testing compounds in different combinations, pooling designs also allow for error-correction. These pooled designs, for specific experiment parameters, can be simply and efficiently created using the Shifted Transversal Design (STD pooling algorithm. However, drug screening contains a number of key constraints that require specific modifications if this pooling approach is to be useful for practical screen designs. Results In this paper, we introduce a pooling strategy called poolHiTS (Pooled High-Throughput Screening which is based on the STD algorithm. In poolHiTS, we implement a limit on the number of compounds that can be mixed in a single assay. In addition, we show that the STD-based pooling strategy is limited in the error-correction that it can achieve. Due to the mixing constraint, we show that it is more efficient to split a large library into smaller blocks of compounds, which are then tested using an optimized strategy repeated for each block. We package the optimal block selection algorithm into poolHiTS. The MATLAB codes for the poolHiTS algorithm and the corresponding decoding strategy are also provided. Conclusion We have produced a practical version

Very Large Data Volumes Analysis of Collaborative Systems with Finite Number of States

Science.gov (United States)

Ivan, Ion; Ciurea, Cristian; Pavel, Sorin

2010-01-01

The collaborative system with finite number of states is defined. A very large database is structured. Operations on large databases are identified. Repetitive procedures for collaborative systems operations are derived. The efficiency of such procedures is analyzed. (Contains 6 tables, 5 footnotes and 3 figures.)

Product-selective blot: a technique for measuring enzyme activities in large numbers of samples and in native electrophoresis gels

International Nuclear Information System (INIS)

Thompson, G.A.; Davies, H.M.; McDonald, N.

1985-01-01

A method termed product-selective blotting has been developed for screening large numbers of samples for enzyme activity. The technique is particularly well suited to detection of enzymes in native electrophoresis gels. The principle of the method was demonstrated by blotting samples from glutaminase or glutamate synthase reactions into an agarose gel embedded with ion-exchange resin under conditions favoring binding of product (glutamate) over substrates and other substances in the reaction mixture. After washes to remove these unbound substances, the product was measured using either fluorometric staining or radiometric techniques. Glutaminase activity in native electrophoresis gels was visualized by a related procedure in which substrates and products from reactions run in the electrophoresis gel were blotted directly into a resin-containing image gel. Considering the selective-binding materials available for use in the image gel, along with the possible detection systems, this method has potentially broad application

Copy number variation of KIR genes influences HIV-1 control

DEFF Research Database (Denmark)

Pelak, Kimberly; Need, Anna C; Fellay, Jacques

2011-01-01

A genome-wide screen for large structural variants showed that a copy number variant (CNV) in the region encoding killer cell immunoglobulin-like receptors (KIR) associates with HIV-1 control as measured by plasma viral load at set point in individuals of European ancestry. This CNV encompasses t...

A Fragment-Based Ligand Screen Against Part of a Large Protein Machine: The ND1 Domains of the AAA+ ATPase p97/VCP.

Science.gov (United States)

Chimenti, Michael S; Bulfer, Stacie L; Neitz, R Jeffrey; Renslo, Adam R; Jacobson, Matthew P; James, Thomas L; Arkin, Michelle R; Kelly, Mark J S

2015-07-01

The ubiquitous AAA+ ATPase p97 functions as a dynamic molecular machine driving several cellular processes. It is essential in regulating protein homeostasis, and it represents a potential drug target for cancer, particularly when there is a greater reliance on the endoplasmic reticulum-associated protein degradation pathway and ubiquitin-proteasome pathway to degrade an overabundance of secreted proteins. Here, we report a case study for using fragment-based ligand design approaches against this large and dynamic hexamer, which has multiple potential binding sites for small molecules. A screen of a fragment library was conducted by surface plasmon resonance (SPR) and followed up by nuclear magnetic resonance (NMR), two complementary biophysical techniques. Virtual screening was also carried out to examine possible binding sites for the experimental hits and evaluate the potential utility of fragment docking for this target. Out of this effort, 13 fragments were discovered that showed reversible binding with affinities between 140 µM and 1 mM, binding stoichiometries of 1:1 or 2:1, and good ligand efficiencies. Structural data for fragment-protein interactions were obtained with residue-specific [U-(2)H] (13)CH3-methyl-labeling NMR strategies, and these data were compared to poses from docking. The combination of virtual screening, SPR, and NMR enabled us to find and validate a number of interesting fragment hits and allowed us to gain an understanding of the structural nature of fragment binding. © 2015 Society for Laboratory Automation and Screening.

Optimal number of coarse-grained sites in different components of large biomolecular complexes.

Science.gov (United States)

Sinitskiy, Anton V; Saunders, Marissa G; Voth, Gregory A

2012-07-26

The computational study of large biomolecular complexes (molecular machines, cytoskeletal filaments, etc.) is a formidable challenge facing computational biophysics and biology. To achieve biologically relevant length and time scales, coarse-grained (CG) models of such complexes usually must be built and employed. One of the important early stages in this approach is to determine an optimal number of CG sites in different constituents of a complex. This work presents a systematic approach to this problem. First, a universal scaling law is derived and numerically corroborated for the intensity of the intrasite (intradomain) thermal fluctuations as a function of the number of CG sites. Second, this result is used for derivation of the criterion for the optimal number of CG sites in different parts of a large multibiomolecule complex. In the zeroth-order approximation, this approach validates the empirical rule of taking one CG site per fixed number of atoms or residues in each biomolecule, previously widely used for smaller systems (e.g., individual biomolecules). The first-order corrections to this rule are derived and numerically checked by the case studies of the Escherichia coli ribosome and Arp2/3 actin filament junction. In different ribosomal proteins, the optimal number of amino acids per CG site is shown to differ by a factor of 3.5, and an even wider spread may exist in other large biomolecular complexes. Therefore, the method proposed in this paper is valuable for the optimal construction of CG models of such complexes.

Improving CASINO performance for models with large number of electrons

International Nuclear Information System (INIS)

Anton, L.; Alfe, D.; Hood, R.Q.; Tanqueray, D.

2009-01-01

Quantum Monte Carlo calculations have at their core algorithms based on statistical ensembles of multidimensional random walkers which are straightforward to use on parallel computers. Nevertheless some computations have reached the limit of the memory resources for models with more than 1000 electrons because of the need to store a large amount of electronic orbitals related data. Besides that, for systems with large number of electrons, it is interesting to study if the evolution of one configuration of random walkers can be done faster in parallel. We present a comparative study of two ways to solve these problems: (1) distributed orbital data done with MPI or Unix inter-process communication tools, (2) second level parallelism for configuration computation

Characterization of General TCP Traffic under a Large Number of Flows Regime

National Research Council Canada - National Science Library

Tinnakornsrisuphap, Peerapol; La, Richard J; Makowski, Armand M

2002-01-01

.... Accurate traffic modeling of a large number of short-lived TCP flows is extremely difficult due to the interaction between session, transport, and network layers, and the explosion of the size...

Simulation and estimation of gene number in a biological pathway using almost complete saturation mutagenesis screening of haploid mouse cells.

Science.gov (United States)

Tokunaga, Masahiro; Kokubu, Chikara; Maeda, Yusuke; Sese, Jun; Horie, Kyoji; Sugimoto, Nakaba; Kinoshita, Taroh; Yusa, Kosuke; Takeda, Junji

2014-11-24

Genome-wide saturation mutagenesis and subsequent phenotype-driven screening has been central to a comprehensive understanding of complex biological processes in classical model organisms such as flies, nematodes, and plants. The degree of "saturation" (i.e., the fraction of possible target genes identified) has been shown to be a critical parameter in determining all relevant genes involved in a biological function, without prior knowledge of their products. In mammalian model systems, however, the relatively large scale and labor intensity of experiments have hampered the achievement of actual saturation mutagenesis, especially for recessive traits that require biallelic mutations to manifest detectable phenotypes. By exploiting the recently established haploid mouse embryonic stem cells (ESCs), we present an implementation of almost complete saturation mutagenesis in a mammalian system. The haploid ESCs were mutagenized with the chemical mutagen N-ethyl-N-nitrosourea (ENU) and processed for the screening of mutants defective in various steps of the glycosylphosphatidylinositol-anchor biosynthetic pathway. The resulting 114 independent mutant clones were characterized by a functional complementation assay, and were shown to be defective in any of 20 genes among all 22 known genes essential for this well-characterized pathway. Ten mutants were further validated by whole-exome sequencing. The predominant generation of single-nucleotide substitutions by ENU resulted in a gene mutation rate proportional to the length of the coding sequence, which facilitated the experimental design of saturation mutagenesis screening with the aid of computational simulation. Our study enables mammalian saturation mutagenesis to become a realistic proposition. Computational simulation, combined with a pilot mutagenesis experiment, could serve as a tool for the estimation of the number of genes essential for biological processes such as drug target pathways when a positive selection of

An experience of qualified preventive screening: shiraz smart screening software.

Science.gov (United States)

Islami Parkoohi, Parisa; Zare, Hashem; Abdollahifard, Gholamreza

2015-01-01

Computerized preventive screening software is a cost effective intervention tool to address non-communicable chronic diseases. Shiraz Smart Screening Software (SSSS) was developed as an innovative tool for qualified screening. It allows simultaneous smart screening of several high-burden chronic diseases and supports reminder notification functionality. The extent in which SSSS affects screening quality is also described. Following software development, preventive screening and annual health examinations of 261 school staff (Medical School of Shiraz, Iran) was carried out in a software-assisted manner. To evaluate the quality of the software-assisted screening, we used quasi-experimental study design and determined coverage, irregular attendance and inappropriateness proportions in relation with the manual and software-assisted screening as well as the corresponding number of requested tests. In manual screening method, 27% of employees were covered (with 94% irregular attendance) while by software-assisted screening, the coverage proportion was 79% (attendance status will clear after the specified time). The frequency of inappropriate screening test requests, before the software implementation, was 41.37% for fasting plasma glucose, 41.37% for lipid profile, 0.84% for occult blood, 0.19% for flexible sigmoidoscopy/colonoscopy, 35.29% for Pap smear, 19.20% for mammography and 11.2% for prostate specific antigen. All of the above were corrected by the software application. In total, 366 manual screening and 334 software-assisted screening tests were requested. SSSS is an innovative tool to improve the quality of preventive screening plans in terms of increased screening coverage, reduction in inappropriateness and the total number of requested tests.

Implementation of nutrition risk screening using the Malnutrition Universal Screening Tool across a large metropolitan health service.

Science.gov (United States)

Cooper, P L; Raja, R; Golder, J; Stewart, A J; Shaikh, R F; Apostolides, M; Savva, J; Sequeira, J L; Silvers, M A

2016-12-01

A standardised nutrition risk screening (NRS) programme with ongoing education is recommended for the successful implementation of NRS. This project aimed to develop and implement a standardised NRS and education process across the adult bed-based services of a large metropolitan health service and to achieve a 75% NRS compliance at 12 months post-implementation. A working party of Monash Health (MH) dietitians and a nutrition technician revised an existing NRS medical record form consisting of the Malnutrition Universal Screening Tool and nutrition management guidelines. Nursing staff across six MH hospital sites were educated in the use of this revised form and there was a formalised implementation process. Support from Executive Management, nurse educators and the Nutrition Risk Committee ensured the incorporation of NRS into nursing practice. Compliance audits were conducted pre- and post-implementation. At 12 months post-implementation, organisation-wide NRS compliance reached 34.3%. For those wards that had pre-implementation NRS performed by nursing staff, compliance increased from 7.1% to 37.9% at 12 months (P Audit', which is reported 6-monthly to the Nutrition Risk Committee and site Quality and Safety Committees. NRS compliance improved at MH with strong governance support and formalised implementation; however, the overall compliance achieved appears to have been affected by the complexity and diversity of multiple healthcare sites. Ongoing education, regular auditing and establishment of NRS routines and ward practices is recommended to further improve compliance. © 2016 The British Dietetic Association Ltd.

Optimization of a Fluorescence-Based Assay for Large-Scale Drug Screening against Babesia and Theileria Parasites.

Science.gov (United States)

Rizk, Mohamed Abdo; El-Sayed, Shimaa Abd El-Salam; Terkawi, Mohamed Alaa; Youssef, Mohamed Ahmed; El Said, El Said El Shirbini; Elsayed, Gehad; El-Khodery, Sabry; El-Ashker, Maged; Elsify, Ahmed; Omar, Mosaab; Salama, Akram; Yokoyama, Naoaki; Igarashi, Ikuo

2015-01-01

A rapid and accurate assay for evaluating antibabesial drugs on a large scale is required for the discovery of novel chemotherapeutic agents against Babesia parasites. In the current study, we evaluated the usefulness of a fluorescence-based assay for determining the efficacies of antibabesial compounds against bovine and equine hemoparasites in in vitro cultures. Three different hematocrits (HCTs; 2.5%, 5%, and 10%) were used without daily replacement of the medium. The results of a high-throughput screening assay revealed that the best HCT was 2.5% for bovine Babesia parasites and 5% for equine Babesia and Theileria parasites. The IC50 values of diminazene aceturate obtained by fluorescence and microscopy did not differ significantly. Likewise, the IC50 values of luteolin, pyronaridine tetraphosphate, nimbolide, gedunin, and enoxacin did not differ between the two methods. In conclusion, our fluorescence-based assay uses low HCT and does not require daily replacement of culture medium, making it highly suitable for in vitro large-scale drug screening against Babesia and Theileria parasites that infect cattle and horses.

Optimization of a Fluorescence-Based Assay for Large-Scale Drug Screening against Babesia and Theileria Parasites.

Directory of Open Access Journals (Sweden)

Mohamed Abdo Rizk

Full Text Available A rapid and accurate assay for evaluating antibabesial drugs on a large scale is required for the discovery of novel chemotherapeutic agents against Babesia parasites. In the current study, we evaluated the usefulness of a fluorescence-based assay for determining the efficacies of antibabesial compounds against bovine and equine hemoparasites in in vitro cultures. Three different hematocrits (HCTs; 2.5%, 5%, and 10% were used without daily replacement of the medium. The results of a high-throughput screening assay revealed that the best HCT was 2.5% for bovine Babesia parasites and 5% for equine Babesia and Theileria parasites. The IC50 values of diminazene aceturate obtained by fluorescence and microscopy did not differ significantly. Likewise, the IC50 values of luteolin, pyronaridine tetraphosphate, nimbolide, gedunin, and enoxacin did not differ between the two methods. In conclusion, our fluorescence-based assay uses low HCT and does not require daily replacement of culture medium, making it highly suitable for in vitro large-scale drug screening against Babesia and Theileria parasites that infect cattle and horses.

High-throughput screening for gene libraries expressing carbohydrate hydrolase activity

NARCIS (Netherlands)

Leemhuis, Hans; Euverink, Gert-Jan W.; Dijkhuizen, Lubbert

2003-01-01

A simple and fast method is described allowing screening of large number of Escherichia coli clones (4000 per day) for the presence of functional or improved carbohydrate hydrolase enzymes. The procedure is relatively cheap and has the advantage that carbohydrate degrading activity can be directly

Modified large number theory with constant G

International Nuclear Information System (INIS)

Recami, E.

1983-01-01

The inspiring ''numerology'' uncovered by Dirac, Eddington, Weyl, et al. can be explained and derived when it is slightly modified so to connect the ''gravitational world'' (cosmos) with the ''strong world'' (hadron), rather than with the electromagnetic one. The aim of this note is to show the following. In the present approach to the ''Large Number Theory,'' cosmos and hadrons are considered to be (finite) similar systems, so that the ratio R-bar/r-bar of the cosmos typical length R-bar to the hadron typical length r-bar is constant in time (for instance, if both cosmos and hadrons undergo an expansion/contraction cycle: according to the ''cyclical big-bang'' hypothesis: then R-bar and r-bar can be chosen to be the maximum radii, or the average radii). As a consequence, then gravitational constant G results to be independent of time. The present note is based on work done in collaboration with P.Caldirola, G. D. Maccarrone, and M. Pavsic

Evaluation of the Optimum Composition of Low-Temperature Fuel Cell Electrocatalysts for Methanol Oxidation by Combinatorial Screening.

Science.gov (United States)

Antolini, Ermete

2017-02-13

Combinatorial chemistry and high-throughput screening represent an innovative and rapid tool to prepare and evaluate a large number of new materials, saving time and expense for research and development. Considering that the activity and selectivity of catalysts depend on complex kinetic phenomena, making their development largely empirical in practice, they are prime candidates for combinatorial discovery and optimization. This review presents an overview of recent results of combinatorial screening of low-temperature fuel cell electrocatalysts for methanol oxidation. Optimum catalyst compositions obtained by combinatorial screening were compared with those of bulk catalysts, and the effect of the library geometry on the screening of catalyst composition is highlighted.

Regulation and practice of X-ray screening in France

International Nuclear Information System (INIS)

Bouvet, E.; Weill, C.; Lefaure, C.

1987-01-01

Trends in radiological mass screening practice in France over the last few years have been two-ways. On one side, the use of radiological diagnosis, the use of which is generally controversial, has continued as in the case of radiological mass screening for pulmonary tuberculosis. However, new practices in the field of radiological screening have developed. Thus the diagnostic usefulness of mammography for cancer of the breast and X-raying the hip for the screening of congenital hip dysplasia, are subject to a wide degree of consensus among specialists, although no regulations have been drawn up in the field. Thus, on the one hand, a large number of items equipment and specialists are available for an activity which may be considered as obsolete (screening for tuberculosis) and, on the other hand, a medical practice is developing with limited equipment. Reorganization may be usefully considered (screening for congenital hip dysplasia, screening for cancer of the breast). This presentation examines radiological screening in France from two points of view: regulation and practice

Feasibility of large-scale screening using N-ERC/mesothelin levels in the blood for the early diagnosis of malignant mesothelioma.

Science.gov (United States)

Imashimizu, Kohta; Shiomi, Kazu; Maeda, Masahiro; Aoki, Naoko; Igarashi, Kiyoko; Suzuki, Fumio; Koizumi, Mitsuru; Suzuki, Kenji; Hino, Okio

2011-05-01

A large-scale screening involving the measurement of N-ERC/mesothelin levels in blood using an ELISA system for the early diagnosis of malignant mesothelioma (MM) was carried out in individuals with a history of employment at construction sites. Approximately 30,000 subjects were screened. Of the 80 subjects with high-risk values, one male patient was diagnosed as having MM based on a PET study and histopathology. This is the first report of the pre-clinical diagnosis of MM based on blood test screening. In addition, plasma levels of N-ERC/mesothelin may be effectively used for monitoring relapse after surgery.

Large Prospective Study of Ovarian Cancer Screening in High-risk Women: CA125 Cut-point Defined by Menopausal Status

Science.gov (United States)

Skates, Steven J.; Mai, Phuong; Horick, Nora K.; Piedmonte, Marion; Drescher, Charles W.; Isaacs, Claudine; Armstrong, Deborah K.; Buys, Saundra S.; Rodriguez, Gustavo C.; Horowitz, Ira R.; Berchuck, Andrew; Daly, Mary B.; Domchek, Susan; Cohn, David E.; Van Le, Linda; Schorge, John O.; Newland, William; Davidson, Susan A.; Barnes, Mack; Brewster, Wendy; Azodi, Masoud; Nerenstone, Stacy; Kauff, Noah D.; Fabian, Carol J.; Sluss, Patrick M.; Nayfield, Susan G.; Kasten, Carol H.; Finkelstein, Dianne M.; Greene, Mark H.; Lu, Karen

2011-01-01

Background Previous screening trials for early detection of ovarian cancer in postmenopausal women have used the standard CA125 cut-point of 35 U/mL, the 98th percentile in this population yielding a 2% false positive rate, while the same cut-point in trials of premenopausal women results in substantially higher false positive rates. We investigated demographic and clinical factors predicting CA125 distributions, including 98th percentiles, in a large population of high-risk women participating in two ovarian cancer screening studies with common eligibility criteria and screening protocols. Methods Baseline CA125 values and clinical and demographic data from 3,692 women participating in screening studies conducted by the NCI-sponsored Cancer Genetics Network and Gynecologic Oncology Group were combined for this pre-planned analysis. Due to the large effect of menopausal status on CA125 levels, statistical analyses were conducted separately in pre- and postmenopausal subjects to determine the impact of other baseline factors on predicted CA125 cut-points based on the 98th percentile. Results The primary clinical factor affecting CA125 cut-points was menopausal status, with premenopausal women having a significantly higher cut-point of 50 U/mL while in postmenopausal subjects the standard cut-point of 35 U/mL was recapitulated. In premenopausal women, current oral contraceptive (OC) users had a cut-point of 40 U/mL. Conclusions To achieve a 2% false positive rate in ovarian cancer screening trials and in high-risk women choosing to be screened, the cut-point for initial CA125 testing should be personalized primarily for menopausal status (~ 50 for premenopausal women, 40 for premenopausal on OC, 35 for postmenopausal women). PMID:21893500

Screening for breast cancer with mammography

International Nuclear Information System (INIS)

Sickles, E.A.

1991-01-01

Mammography is generally accepted as a useful problem-solving clinical tool in characterizing known breast lesions, so that appropriate and timely treatment can be given. However, it remains grossly underutilized at what it does best: screening. The major strengths of mammography are (a) its ability to detect breast cancer at a smaller, potentially more curable stage than any other examination, and (b) its proved efficacy in reducing breast cancer mortality in asymptomatic women aged 40-74. If, as has recently been estimated, screening with mammography and physical examination can be expected to lower breast cancer deaths by 40%-50% among those actually examined (13), then the lives of almost 20,000 U.S. women might be saved each year if screening were to become very widely used. The challenges of the next decade are clear, to mount much more effective campaigns to educate physicians and lay women about the life-saving benefits of breast cancer screening, to devise increasingly effective and lower cost screening strategies, to further improve the current high quality of mammographic imaging despite its increasing proliferation, and to train large numbers of breast imaging specialists to guarantee that the growing case load of screening and problem-solving mammograms is interpreted with a very high level of skill

Breakdown of the law of large numbers in Josephson junction series arrays

International Nuclear Information System (INIS)

Dominguez, D.; Cerdeira, H.A.

1994-01-01

We study underdamped Josephson junction series arrays that are globally coupled through a resistive shunting load and driven by an rf bias current. We find that they can be an experimental realization of many phenomena currently studied in globally coupled logistic maps. We find coherent, ordered, partially ordered and turbulent phases in the IV characteristics of the array. The ordered phase corresponds to giant Shapiro steps. In the turbulent phase there is a saturation of the broad band noise for a large number of junctions. This corresponds to a break down of the law of large numbers as seen in the globally coupled maps. Coexisting with this, we find an emergence of novel pseudo-steps in the IV characteristics. This effect can be experimentally distinguished from the Shapiro steps, which do not have broad band noise emission. (author). 21 refs, 5 figs

A Characterization of Hypergraphs with Large Domination Number

Directory of Open Access Journals (Sweden)

Henning Michael A.

2016-05-01

Full Text Available Let H = (V, E be a hypergraph with vertex set V and edge set E. A dominating set in H is a subset of vertices D ⊆ V such that for every vertex v ∈ V \\ D there exists an edge e ∈ E for which v ∈ e and e ∩ D ≠ ∅. The domination number γ(H is the minimum cardinality of a dominating set in H. It is known [Cs. Bujtás, M.A. Henning and Zs. Tuza, Transversals and domination in uniform hypergraphs, European J. Combin. 33 (2012 62-71] that for k ≥ 5, if H is a hypergraph of order n and size m with all edges of size at least k and with no isolated vertex, then γ(H ≤ (n + ⌊(k − 3/2⌋m/(⌊3(k − 1/2⌋. In this paper, we apply a recent result of the authors on hypergraphs with large transversal number [M.A. Henning and C. Löwenstein, A characterization of hypergraphs that achieve equality in the Chvátal-McDiarmid Theorem, Discrete Math. 323 (2014 69-75] to characterize the hypergraphs achieving equality in this bound.

Closing the feedback loop: engaging students in large first-year mathematics test revision sessions using pen-enabled screens

Science.gov (United States)

Donovan, Diane; Loch, Birgit

2013-01-01

How can active learning, peer learning and prompt feedback be achieved in large first-year mathematics classes? Further, what technologies may support these aims? In this article, we assert that test revision sessions in first-year mathematics held in a technology-enhanced lecture theatre can be highly interactive with students solving problems, learning from each other and receiving immediate feedback. This is facilitated by pen-enabled screens and synchronization software. We argue that the educational benefits achievable through the technology do outweigh the technological distractions, and that these benefits can be achieved by focused, targeted one-off sessions and not only by a semester-long, regular approach. Repeat mid-semester test revision sessions were offered on a non-compulsory basis using pen-enabled screens for all students. Students worked practice test questions and marked solutions to mathematical problems on the screens. Students' work was then displayed anonymously for their peers to see. Answers were discussed with the whole class. We discuss outcomes from two offerings of these sessions using student feedback and lecturer reflections and show the impact of participation on self-reported student confidence. Pedagogical approaches that the technology allowed for the first time in a large class are highlighted. Students responded uniformly positively.

Loss of locality in gravitational correlators with a large number of insertions

Science.gov (United States)

Ghosh, Sudip; Raju, Suvrat

2017-09-01

We review lessons from the AdS/CFT correspondence that indicate that the emergence of locality in quantum gravity is contingent upon considering observables with a small number of insertions. Correlation functions, where the number of insertions scales with a power of the central charge of the CFT, are sensitive to nonlocal effects in the bulk theory, which arise from a combination of the effects of the bulk Gauss law and a breakdown of perturbation theory. To examine whether a similar effect occurs in flat space, we consider the scattering of massless particles in the bosonic string and the superstring in the limit, where the number of external particles, n, becomes very large. We use estimates of the volume of the Weil-Petersson moduli space of punctured Riemann surfaces to argue that string amplitudes grow factorially in this limit. We verify this factorial behavior through an extensive numerical analysis of string amplitudes at large n. Our numerical calculations rely on the observation that, in the large n limit, the string scattering amplitude localizes on the Gross-Mende saddle points, even though individual particle energies are small. This factorial growth implies the breakdown of string perturbation theory for n ˜(M/plE ) d -2 in d dimensions, where E is the typical individual particle energy. We explore the implications of this breakdown for the black hole information paradox. We show that the loss of locality suggested by this breakdown is precisely sufficient to resolve the cloning and strong subadditivity paradoxes.

Calculation of large Reynolds number two-dimensional flow using discrete vortices with random walk

International Nuclear Information System (INIS)

Milinazzo, F.; Saffman, P.G.

1977-01-01

The numerical calculation of two-dimensional rotational flow at large Reynolds number is considered. The method of replacing a continuous distribution of vorticity by a finite number, N, of discrete vortices is examined, where the vortices move under their mutually induced velocities plus a random component to simulate effects of viscosity. The accuracy of the method is studied by comparison with the exact solution for the decay of a circular vortex. It is found, and analytical arguments are produced in support, that the quantitative error is significant unless N is large compared with a characteristic Reynolds number. The mutually induced velocities are calculated by both direct summation and by the ''cloud in cell'' technique. The latter method is found to produce comparable error and to be much faster

A large number of stepping motor network construction by PLC

Science.gov (United States)

Mei, Lin; Zhang, Kai; Hongqiang, Guo

2017-11-01

In the flexible automatic line, the equipment is complex, the control mode is flexible, how to realize the large number of step and servo motor information interaction, the orderly control become a difficult control. Based on the existing flexible production line, this paper makes a comparative study of its network strategy. After research, an Ethernet + PROFIBUSE communication configuration based on PROFINET IO and profibus was proposed, which can effectively improve the data interaction efficiency of the equipment and stable data interaction information.

Prospectus: towards the development of high-fidelity models of wall turbulence at large Reynolds number.

Science.gov (United States)

Klewicki, J C; Chini, G P; Gibson, J F

2017-03-13

Recent and on-going advances in mathematical methods and analysis techniques, coupled with the experimental and computational capacity to capture detailed flow structure at increasingly large Reynolds numbers, afford an unprecedented opportunity to develop realistic models of high Reynolds number turbulent wall-flow dynamics. A distinctive attribute of this new generation of models is their grounding in the Navier-Stokes equations. By adhering to this challenging constraint, high-fidelity models ultimately can be developed that not only predict flow properties at high Reynolds numbers, but that possess a mathematical structure that faithfully captures the underlying flow physics. These first-principles models are needed, for example, to reliably manipulate flow behaviours at extreme Reynolds numbers. This theme issue of Philosophical Transactions of the Royal Society A provides a selection of contributions from the community of researchers who are working towards the development of such models. Broadly speaking, the research topics represented herein report on dynamical structure, mechanisms and transport; scale interactions and self-similarity; model reductions that restrict nonlinear interactions; and modern asymptotic theories. In this prospectus, the challenges associated with modelling turbulent wall-flows at large Reynolds numbers are briefly outlined, and the connections between the contributing papers are highlighted.This article is part of the themed issue 'Toward the development of high-fidelity models of wall turbulence at large Reynolds number'. © 2017 The Author(s).

The large number hypothesis and Einstein's theory of gravitation

International Nuclear Information System (INIS)

Yun-Kau Lau

1985-01-01

In an attempt to reconcile the large number hypothesis (LNH) with Einstein's theory of gravitation, a tentative generalization of Einstein's field equations with time-dependent cosmological and gravitational constants is proposed. A cosmological model consistent with the LNH is deduced. The coupling formula of the cosmological constant with matter is found, and as a consequence, the time-dependent formulae of the cosmological constant and the mean matter density of the Universe at the present epoch are then found. Einstein's theory of gravitation, whether with a zero or nonzero cosmological constant, becomes a limiting case of the new generalized field equations after the early epoch

Expanded newborn screening: social and ethical issues.

Science.gov (United States)

Dhondt, Jean-Louis

2010-10-01

Newborn screening and genetic testing have expanded rapidly in the last decade with the advent of multiplex (e.g., tandem mass spectrometry) and/or DNA technologies. However, screening panels include a large number of disorders, which may not meet all of the traditional screening criteria, established in late 1960s, and used for years to justify screening programs. After a period of expansion driven by technological advances, many reports have reconsidered the justification of expanded programs. Many factors have contributed to test-panel discrepancies between countries. The test-panel review methodology, the way health benefits are weighed against harms, and the socioeconomic-political environment all play a role. Expansion of screening also requires reconsideration of the infrastructure (ideally, in the context of national plans for rare diseases) to support testing, counselling, education, treatment, and follow-up. Consequently, economic aspects cannot be ignored and can be a limitation for expansion. New ethical questions have emerged: risks of discrimination or stigmatization, respect of the autonomy of persons to make decisions, parental anxiety resulting from a false positive test (especially when reporting to parents screening results for untreatable conditions identified as by-products of screening), etc. For disorders where there is not yet confirmation of benefit, it may be prudent to recommend pilot screening and to have a mechanism that can be used to adapt or even to stop a program.

Genealogical series method. Hyperpolar points screen effect

International Nuclear Information System (INIS)

Gorbatov, A.M.

1991-01-01

The fundamental values of the genealogical series method -the genealogical integrals (sandwiches) have been investigated. The hyperpolar points screen effect has been found. It allows one to calculate the sandwiches for the Fermion systems with large number of particles and to ascertain the validity of the iterated-potential method as well. For the first time the genealogical-series method has been realized numerically for the central spin-independent potential

Abnormal screening in the quantum disordered phases of nonlinear σ-models

International Nuclear Information System (INIS)

Wen, X.G.; Zee, A.

1989-01-01

We study some properties of the quantum disordered phase of nonlinear σ-models, focussing on the quantum numbers of the quasi-particles and possible experimental implications. We find that the quasi-particles in the quantum disordered phase may, in many cases, carry new quantum numbers which do not appear in any finite combination of the fundamental fields. We call this phenomenon abnormal screening. Abnormal screening is shown to appear in (1+1)-dimensional systems. Using a large N mean field approach to the quantum disordered state, we show that abnormal screening may also appear in (1+2)-dimensional nonlinear σ-models. In 1+2 dimensions abnormal screening is closely related to spin-charge separation, which was proposed to occur in the spin liquid state relevant in some theories of high T c superconductivity. We compare the mean field approach with bosonization and other exact results for (1+1)-dimensional systems and find exact agreement for the quantum numbers of the quasi-particles. This suggests that mean field analysis of high T c superconductivity may yield a qualitatively reliable picture. Our result also gives an alternative way of understanding some novel properties of the antiferromagnetic spin chain. We estimate the density and temperature at which deconfinement and abnormal screening occur. Finally, we suggest some experimental signatures for this phenomenon. (orig.)

Digital radiography with a large-scale electronic flat-panel detector vs screen-film radiography: observer preference in clinical skeletal diagnostics

International Nuclear Information System (INIS)

Hamers, S.; Freyschmidt, J.; Neitzel, U.

2001-01-01

The imaging performance of a recently developed digital flat-panel detector system was compared with conventional screen-film imaging in an observer preference study. In total, 34 image pairs of various regions of the skeleton were obtained in 24 patients; 30 image pairs were included in the study. The conventional images were acquired with 250- and 400-speed screen-film combinations, using the standard technique of our department. Within hours, the digital images were obtained using identical exposure parameters. The digital system employed a large-area (43 x 43 cm) flat-panel detector based on amorphous silicon (Trixell Pixium 4600), integrated in a Bucky table. Six radiologists independently evaluated the image pairs with respect to image latitude, soft tissue rendition, rendition of the periosteal and enosteal border of cortical bone, rendition of cancellous bone and the visibility of potentially present pathological changes, using a subjective five-point scale. The digital images were rated significantly (p=0.001) better than the screen-film images with respect to soft tissue rendition and image latitude. Also the rendition of the cancellous bone and the periosteal and enosteal border of the cortical bone was rated significantly (p=0.05) better for the flat-panel detector. The visibility of pathological lesions was equivalent; only large-area sclerotic lesions (n=2) were seen superiorly on screen-film images. The new digital flat-panel detector based on amorphous silicon appears to be at least equivalent to conventional screen-film combinations for skeletal examinations, and in most respects even superior. (orig.)

Noise of screen-film systems: origins and components

Energy Technology Data Exchange (ETDEWEB)

Kuhn, H

1983-01-01

When using the more sensitive rare-earth intensifying screens in radiography applying the screen-film system, one has to cope with an increase in quantum noise. Measurement of Wiener spectra will help to determine the noise of the film. With an appropriate apparatus, the noise spectra of screen-film systems of different sensitivity have been ascertained and compared with theoretical assessments. The integral noise made up of the components film noise, screen noise and quantum noise have been thoroughly analysed. Adequate choice of radiographic conditions (such as modification of film exposure time via the screen, change of tube voltage) will affect the number of absorbed X-ray quanta in the luminous substance and thus the quantum noise which, as was found out, largely contributes to the integral noise together with another factor, graininess of the film. The study shows that although quantum noise has to be cut back, this should not be done at any price, and due regard must be paid to other factors influencing the image quality of the system, such as contrast and MTF.

Radioimmunoassay of h-TSH - methodological suggestions for dealing with medium to large numbers of samples

International Nuclear Information System (INIS)

Mahlstedt, J.

1977-01-01

The article deals with practical aspects of establishing a TSH-RIA for patients, with particular regard to predetermined quality criteria. Methodological suggestions are made for medium to large numbers of samples with the target of reducing monotonous precision working steps by means of simple aids. The quality criteria required are well met, while the test procedure is well adapted to the rhythm of work and may be carried out without loss of precision even with large numbers of samples. (orig.) [de

Screening of colorectal early cancer by radiology

International Nuclear Information System (INIS)

Matsukawa, M.; Usui, Y.; Kobayashi, S.

1988-01-01

The incidence of colorectal cancer has been gradually increasing in Japan, and if the present rate of increase is maintained it has been estimated that it will become the most common of all malignant neoplasms by the year 2000. It has been proved that colorectal cancer can be completely cured, if it is treated in its early phase. Early cancer of the large bowel is defined as a cancer which is limited to the mucosal membrane or submucosal layer, regardless of lymph node and distant metastases. Detection of early cancer improves the overall curability of colorectal cancer. The greatest number of early cancers of the large bowel are polypoid lesions in their macroscopic form, and depressed lesions are rarely encountered. Accordingly, the first step in the detection of early cancer starts with the screening of polypoid lesion by radiology and endoscopy. This paper is concerned with diagnostic accuracy of radiology in the screening of colorectal cancer with endoscopic correlation

Rod-coating: towards large-area fabrication of uniform reduced graphene oxide films for flexible touch screens.

Science.gov (United States)

Wang, Jie; Liang, Minghui; Fang, Yan; Qiu, Tengfei; Zhang, Jin; Zhi, Linjie

2012-06-05

A novel strategy is developed for the large-scale fabrication of reduced graphene oxide films directly on flexible substrates in a controlled manner by the combination of a rod-coating technique and room-temperature reduction of graphene oxide. The as-prepared films display excellent uniformity, good transparency and conductivity, and great flexibility in a touch screen. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hierarchies in Quantum Gravity: Large Numbers, Small Numbers, and Axions

Science.gov (United States)

Stout, John Eldon

Our knowledge of the physical world is mediated by relatively simple, effective descriptions of complex processes. By their very nature, these effective theories obscure any phenomena outside their finite range of validity, discarding information crucial to understanding the full, quantum gravitational theory. However, we may gain enormous insight into the full theory by understanding how effective theories with extreme characteristics--for example, those which realize large-field inflation or have disparate hierarchies of scales--can be naturally realized in consistent theories of quantum gravity. The work in this dissertation focuses on understanding the quantum gravitational constraints on these "extreme" theories in well-controlled corners of string theory. Axion monodromy provides one mechanism for realizing large-field inflation in quantum gravity. These models spontaneously break an axion's discrete shift symmetry and, assuming that the corrections induced by this breaking remain small throughout the excursion, create a long, quasi-flat direction in field space. This weakly-broken shift symmetry has been used to construct a dynamical solution to the Higgs hierarchy problem, dubbed the "relaxion." We study this relaxion mechanism and show that--without major modifications--it can not be naturally embedded within string theory. In particular, we find corrections to the relaxion potential--due to the ten-dimensional backreaction of monodromy charge--that conflict with naive notions of technical naturalness and render the mechanism ineffective. The super-Planckian field displacements necessary for large-field inflation may also be realized via the collective motion of many aligned axions. However, it is not clear that string theory provides the structures necessary for this to occur. We search for these structures by explicitly constructing the leading order potential for C4 axions and computing the maximum possible field displacement in all compactifications of

Prospectus: towards the development of high-fidelity models of wall turbulence at large Reynolds number

Science.gov (United States)

Klewicki, J. C.; Chini, G. P.; Gibson, J. F.

2017-01-01

Recent and on-going advances in mathematical methods and analysis techniques, coupled with the experimental and computational capacity to capture detailed flow structure at increasingly large Reynolds numbers, afford an unprecedented opportunity to develop realistic models of high Reynolds number turbulent wall-flow dynamics. A distinctive attribute of this new generation of models is their grounding in the Navier–Stokes equations. By adhering to this challenging constraint, high-fidelity models ultimately can be developed that not only predict flow properties at high Reynolds numbers, but that possess a mathematical structure that faithfully captures the underlying flow physics. These first-principles models are needed, for example, to reliably manipulate flow behaviours at extreme Reynolds numbers. This theme issue of Philosophical Transactions of the Royal Society A provides a selection of contributions from the community of researchers who are working towards the development of such models. Broadly speaking, the research topics represented herein report on dynamical structure, mechanisms and transport; scale interactions and self-similarity; model reductions that restrict nonlinear interactions; and modern asymptotic theories. In this prospectus, the challenges associated with modelling turbulent wall-flows at large Reynolds numbers are briefly outlined, and the connections between the contributing papers are highlighted. This article is part of the themed issue ‘Toward the development of high-fidelity models of wall turbulence at large Reynolds number’. PMID:28167585

Between Stage and Screen

NARCIS (Netherlands)

Tornqvist, Egil

1996-01-01

Ingmar Bergman is worldwide known as a film and stage director. Yet no-one has attempted to compare his stage and screen activities. In Between stage and screen Egil Tornqvist examines formal and thematical correspondences and differences between a number of Bergman's stage, screen, and radio

Large multitouch screens to enhance collaboration in the classroom of the 21st century: an Italian experiment

Directory of Open Access Journals (Sweden)

Alessandra Agostini

2013-02-01

Full Text Available Thanks to technology-pervaded learning environments, digital natives can experiment new engaging ways of learning together at school. In particular, large displays with multi-touch technology hold new opportunities for the learning process, through the dialogic interaction between students and the simultaneous physical interaction with the screen. Our research suggests the use of a context-aware platform with multi-touch displays to support digital storytelling, in order to increase students’ involvement, motivation, and participation. We start our work by designing an application to create fairytales using multi-touch screens, to stimulate new collaboration opportunities during everyday classroom activities. The paper presents the results of an experiment with Interactive WhiteBoards (IWBs, carried out in an Italian primary school.

Law of Large Numbers: the Theory, Applications and Technology-based Education.

Science.gov (United States)

Dinov, Ivo D; Christou, Nicolas; Gould, Robert

2009-03-01

Modern approaches for technology-based blended education utilize a variety of recently developed novel pedagogical, computational and network resources. Such attempts employ technology to deliver integrated, dynamically-linked, interactive-content and heterogeneous learning environments, which may improve student comprehension and information retention. In this paper, we describe one such innovative effort of using technological tools to expose students in probability and statistics courses to the theory, practice and usability of the Law of Large Numbers (LLN). We base our approach on integrating pedagogical instruments with the computational libraries developed by the Statistics Online Computational Resource (www.SOCR.ucla.edu). To achieve this merger we designed a new interactive Java applet and a corresponding demonstration activity that illustrate the concept and the applications of the LLN. The LLN applet and activity have common goals - to provide graphical representation of the LLN principle, build lasting student intuition and present the common misconceptions about the law of large numbers. Both the SOCR LLN applet and activity are freely available online to the community to test, validate and extend (Applet: http://socr.ucla.edu/htmls/exp/Coin_Toss_LLN_Experiment.html, and Activity: http://wiki.stat.ucla.edu/socr/index.php/SOCR_EduMaterials_Activities_LLN).

Break down of the law of large numbers in Josephson junction series arrays

International Nuclear Information System (INIS)

Dominguez, D.; Cerdeira, H.A.

1995-01-01

We study underdamped Josephson junction series arrays that are globally coupled through a resistive shunting load and driven by an rf bias current. We find that they can be an experimental realization of many phenomena currently studied in globally coupled logistic maps. We find coherent, ordered, partially ordered and turbulent phases in the IV characteristics of the array. The ordered phase corresponds to giant Shapiro steps. In the turbulent phase there is a saturation of the broad band noise for a large number of junctions. This corresponds to a break down of the law of large numbers as seen in globally coupled maps. Coexisting with this, we find an emergence of novel pseudo-steps in the IV characteristics. This effect can be experimentally distinguished from the true Shapiro steps, which do not have broad band noise emission. (author). 21 refs, 5 figs

Screening for influenza viruses in 7804 patients with influenza-like symptoms

International Nuclear Information System (INIS)

Xuehui Li; Nan Lv; Chen Hangwe; Lanhua You; Huimin Wang

2010-01-01

To screen a large number of patients with influenza-like symptoms by using the gold-immunochromatographic assay kit. All patients with influenza-like symptoms visiting the outpatient department of the General Hospital of Beijing Military Region, Beijing, China between May 2009 and January 2010 were enrolled in the study. Nasopharyngeal swabs were collected immediately after the patient visited, then a gold-immunochromatographic assay was performed for screening of influenza A and B viruses according to the kit protocol. Among the 7804 patients enrolled in this study, 202 patients were influenza virus-positive; the positive cases accounted for 2.6% of all cases detected. Among the 202 influenza virus-positive patients, 171 patients were influenza virus A-positive, 24 were influenza virus B-positive, and 7 were co-infected with influenza virus A and B. More than 57% of the virus-positive patients were younger than 30 years old. Symptoms such as fever, sore throat, nasal congestion, sneezing, runny nose, and joint pain were more frequently observed in influenza virus A-positive patients than in influenza virus B-positive and influenza virus-negative patients. The gold immunochromatographic assay kit is very useful for screening a large number of patients with influenza-like symptoms. A higher number of influenza virus A-positive patients have sore throat, nasal congestion, sneezing, runny nose, and joint pain than influenza virus B-positive and influenza virus-negative patients (Author).

The lore of large numbers: some historical background to the anthropic principle

International Nuclear Information System (INIS)

Barrow, J.D.

1981-01-01

A description is given of how the study of numerological coincidences in physics and cosmology led first to the Large Numbers Hypothesis of Dirac and then to the suggestion of the Anthropic Principle in a variety of forms. The early history of 'coincidences' is discussed together with the work of Weyl, Eddington and Dirac. (author)

[Diabetes screening and prevention in a large chemical company].

Science.gov (United States)

Neumann, S; Webendörfer, S; Lang, S; Germann, C; Oberlinner, C

2015-05-01

Diabetes is with 6 million cases in Germany one of the most common and most expensive chronic diseases. Studies presume a high number of unreported cases. Early detection of diabetes with a specific screening method is very important. In Germany family physicians offer a preventive check-up starting at the age of 35 years but only 19% males participate. From this background the BASF department for Occupational Medicine and Health Protection introduced for all 35.000 employees at the headquarter, in Ludwigshafen a general health check focused on the early detection of lifestyle diseases. From April 2011 to June 2013 12.114 employees participated in the general health check offered by the medical department (2.530 women, 9.584 men). All participants filled out a questionnaire named "Findrisk" a scientifically validated questionnaire which focuses on risk factors for diabetes. Furthermore, the blood glucose and the HbA1c of the participants have also been checked in a laboratory test Following the Findrisk criteria the results are: 1.368 employees had an elevated risk of 17%, 854 employees a risk factor of 33% and 131 employees a risk factor of 33%. In 1.533 employees (13,2% of all participants) we diagnosed a prediabetes with an elevated HbA1c-parameter between 5.7 to 6,4%. In 243 employees a manifest diabetes disease with HbA1c of > than 6,5% was diagnosed. We found out that diabetes prevention within the workplace setting is helpful to detect prediabetes and diabetes earlier than family doctors outside the company are able to do.Occupational physicians have the opportunity to inform the employees on risks for lifestyle diseases at an early stage when they are still healthy (primary prevention).For secondary prevention surveillance and clearance examination can be easily combined with screening tests for diabetes. For further diagnostics and therapy the family doctors will be addressed. This system helps individuals to prevent negative health effects, it helps the

Does screen size matter for smartphones? Utilitarian and hedonic effects of screen size on smartphone adoption.

Science.gov (United States)

Kim, Ki Joon; Sundar, S Shyam

2014-07-01

This study explores the psychological effects of screen size on smartphone adoption by proposing an extended Technology Acceptance Model (TAM) that integrates an empirical comparison between large and small screens with perceived control, affective quality, and the original TAM constructs. A structural equation modeling analysis was conducted on data collected from a between-subjects experiment (N=130) in which users performed a web-based task on a smartphone with either a large (5.3 inches) or a small (3.7 inches) screen. Results show that a large screen, compared to a small screen, is likely to lead to higher smartphone adoption by simultaneously promoting both the utilitarian and hedonic qualities of smartphones, which in turn positively influence perceived ease of use of-and attitude toward-the device respectively. Implications and directions for future research are discussed.

Cost-effectiveness analysis of the optimal threshold of an automated immunochemical test for colorectal cancer screening: performances of immunochemical colorectal cancer screening.

Science.gov (United States)

Berchi, Célia; Guittet, Lydia; Bouvier, Véronique; Launoy, Guy

2010-01-01

Most industrialized countries, including France, have undertaken to generalize colorectal cancer screening using guaiac fecal occult blood tests (G-FOBT). However, recent researches demonstrate that immunochemical fecal occult blood tests (I-FOBT) are more effective than G-FOBT. Moreover, new generation I-FOBT benefits from a quantitative reading technique allowing the positivity threshold to be chosen, hence offering the best balance between effectiveness and cost. We aimed at comparing the cost and the clinical performance of one round of screening using I-FOBT at different positivity thresholds to those obtained with G-FOBT to determine the optimal cut-off for I-FOBT. Data were derived from an experiment conducted from June 2004 to December 2005 in Calvados (France) where 20,322 inhabitants aged 50-74 years performed both I-FOBT and G-FOBT. Clinical performance was assessed by the number of advanced tumors screened, including large adenomas and cancers. Costs were assessed by the French Social Security Board and included only direct costs. Screening using I-FOBT resulted in better health outcomes and lower costs than screening using G-FOBT for thresholds comprised between 75 and 93 ng/ml. I-FOBT at 55 ng/ml also offers a satisfactory alternative to G-FOBT, because it is 1.8-fold more effective than G-FOBT, without increasing the number of unnecessary colonoscopies, and at an extra cost of 2,519 euros per advanced tumor screened. The use of an automated I-FOBT at 75 ng/ml would guarantee more efficient screening than currently used G-FOBT. Health authorities in industrialized countries should consider the replacement of G-FOBT by an automated I-FOBT test in the near future.

Reply: Comparison of slope instability screening tools following a large storm event and application to forest management and policy

Science.gov (United States)

Whittaker, Kara A.; McShane, Dan

2013-02-01

A large storm event in southwest Washington State triggered over 2500 landslides and provided an opportunity to assess two slope stability screening tools. The statistical analysis conducted demonstrated that both screening tools are effective at predicting where landslides were likely to take place (Whittaker and McShane, 2012). Here we reply to two discussions of this article related to the development of the slope stability screening tools and the accuracy and scale of the spatial data used. Neither of the discussions address our statistical analysis or results. We provide greater detail on our sampling criteria and also elaborate on the policy and management implications of our findings and how they complement those of a separate investigation of landslides resulting from the same storm. The conclusions made in Whittaker and McShane (2012) stand as originally published unless future analysis indicates otherwise.

Low Yield of Chest Radiography in a Large Tuberculosis Screening Program1

Science.gov (United States)

Pollock, Nira R.

2010-01-01

Purpose: To assess the frequency and spectrum of abnormalities on routine screening chest radiographs in the pre-employment evaluation of health care workers with positive tuberculin skin test (TST) results. Materials and Methods: The institutional review board approved this HIPAA-compliant retrospective study and waived the need for written informed patient consent. Chest radiographic reports of all 2586 asymptomatic individuals with positive TST results who underwent pre-employment evaluation between January 1, 2003, and December 31, 2007, were evaluated to determine the frequency of detection of evidence of active tuberculosis (TB) or latent TB infection (LTBI) and the spectrum of imaging findings. All chest radiographs interpreted as positive were reviewed by an experienced board-certified radiologist. If there was a discrepancy between the two readings, a second experienced radiologist served as an independent and final arbiter. Any follow-up chest radiographs or computed tomographic images that had been acquired by employee health services or by the employee’s private physician as a result of a suspected abnormality detected at initial screening were also evaluated. Results: Of the 159 (6.1%) chest radiographic examinations that yielded abnormal results, there were no findings that were consistent with active TB. There were 92 cases of calcified granulomas, calcified lymph nodes, or both; 25 cases of apical pleural thickening; 16 cases of fibrous scarring; and 31 cases of noncalcified nodules. All cases of fibrous scarring involved an area smaller than 2 cm2. All noncalcified nodules were 4 mm in diameter or smaller, with the exception of one primary lung malignancy and one necrotizing granuloma (negative for acid-fast bacilli) that grew Mycobacterium kansasii on culture. Conclusion: Universal chest radiography in a large pre-employment TB screening program was of low yield in the detection of active TB or increased LTBI reactivation risk, and it provided

Conformal window in QCD for large numbers of colors and flavors

International Nuclear Information System (INIS)

Zhitnitsky, Ariel R.

2014-01-01

We conjecture that the phase transitions in QCD at large number of colors N≫1 is triggered by the drastic change in the instanton density. As a result of it, all physical observables also experience some sharp modification in the θ behavior. This conjecture is motivated by the holographic model of QCD where confinement–deconfinement phase transition indeed happens precisely at temperature T=T c where θ-dependence of the vacuum energy experiences a sudden change in behavior: from N 2 cos(θ/N) at T c to cosθexp(−N) at T>T c . This conjecture is also supported by recent lattice studies. We employ this conjecture to study a possible phase transition as a function of κ≡N f /N from confinement to conformal phase in the Veneziano limit N f ∼N when number of flavors and colors are large, but the ratio κ is finite. Technically, we consider an operator which gets its expectation value solely from non-perturbative instanton effects. When κ exceeds some critical value κ>κ c the integral over instanton size is dominated by small-size instantons, making the instanton computations reliable with expected exp(−N) behavior. However, when κ c , the integral over instanton size is dominated by large-size instantons, and the instanton expansion breaks down. This regime with κ c corresponds to the confinement phase. We also compute the variation of the critical κ c (T,μ) when the temperature and chemical potential T,μ≪Λ QCD slightly vary. We also discuss the scaling (x i −x j ) −γ det in the conformal phase

Ag paste-based nanomesh electrodes for large-area touch screen panels

International Nuclear Information System (INIS)

Chung, Sung-il; Kim, Pan Kyeom; Ha, Tae-gyu

2017-01-01

This study reports a novel method for fabricating a nickel nanomesh mold using phase shift lithography, suitable for use in large-area touch screen panel applications. Generally, the values of light transmittance and sheet resistance of metal mesh transparent conducting electrode (TCE) films are determined by the ratio of the aperture to metal areas. In this study, taking into consideration the optimal light transmittance, sheet resistance, and pattern visibility issues, the line width of the metal mesh pattern was ∼1 µ m, and the pitch of the pattern was ∼100 µ m. In addition, a novel method of manufacturing wiring electrodes using a phase shift lithography process was also developed and evaluated. A TCE film with a size of 370 mm  ×  470 mm was prepared and evaluated for its light transmittance and sheet resistance. In addition, wiring electrodes with a length of 70 mm were fabricated and their line resistances evaluated by varying their line width. (paper)

Ag paste-based nanomesh electrodes for large-area touch screen panels

Science.gov (United States)

Chung, Sung-il; Kyeom Kim, Pan; Ha, Tae-gyu

2017-10-01

This study reports a novel method for fabricating a nickel nanomesh mold using phase shift lithography, suitable for use in large-area touch screen panel applications. Generally, the values of light transmittance and sheet resistance of metal mesh transparent conducting electrode (TCE) films are determined by the ratio of the aperture to metal areas. In this study, taking into consideration the optimal light transmittance, sheet resistance, and pattern visibility issues, the line width of the metal mesh pattern was ~1 µm, and the pitch of the pattern was ~100 µm. In addition, a novel method of manufacturing wiring electrodes using a phase shift lithography process was also developed and evaluated. A TCE film with a size of 370 mm  ×  470 mm was prepared and evaluated for its light transmittance and sheet resistance. In addition, wiring electrodes with a length of 70 mm were fabricated and their line resistances evaluated by varying their line width.

A simple method to estimate the episode and programme sensitivity of breast cancer screening programmes.

Science.gov (United States)

Zorzi, Manuel; Guzzinati, Stefano; Puliti, Donella; Paci, Eugenio

2010-01-01

The estimation of breast cancer screening sensitivity is a major aim in the quality assessment of screening programmes. The proportional incidence method for the estimation of the sensitivity of breast cancer screening programmes is rarely used to estimate the underlying incidence rates. We present a method to estimate episode and programme sensitivity of screening programmes, based solely on cancers detected within screening cycles (excluding breast cancer cases at prevalent screening round) and on the number of incident cases in the total target population (steady state). The assumptions, strengths and limitations of the method are discussed. An example of calculation of episode and programme sensitivities is given, on the basis of the data from the IMPACT study, a large observational study of breast cancer screening programmes in Italy. The programme sensitivity from the fifth year of screening onwards ranged between 41% and 48% of the total number of cases in the target population. At steady state episode sensitivity was 0.70, with a trend across age groups, with lowest values in women aged 50-54 years (0.52) and highest in those 65-69 (0.77). The method is a very serviceable tool for estimating sensitivity in service screening programmes, and the results are comparable with those of other methods of estimation.

Screening for abdominalt aortaaneurisme

DEFF Research Database (Denmark)

Lindholt, Jes Sanddal; Juul, Søren; Henneberg, E W

1997-01-01

In spite of increasing number of elective resections of abdominal aortic aneurysms (AAA) the mortality or ruptured AAA is increasing. The advantages of elective operations are obvious; the lethality is 2-6% while the lethality of ruptured AAA is 75-95%. However, AAA seldom causes symptoms before...... rupture. Ultrasonographic screening for AAA takes 10 minutes per scan, and the sensitivity and specificity are high. Ultrasonographic screening for AAA is a reliable, safe and inexpensive method for screening, and screening for AAA is discussed worldwide. One point four percent of deaths among men from 65...... to 80 year of age are caused by ruptured AAA. Screening men over 65 for AAA can theoretically prevent a substantial number of deaths. Our calculations predict one prevented AAA-death per 200-300 scans for a cost of about 4000 DKK per saved year of life. However, cost-benefit analyses are based...

Screening fifth forces in k-essence and DBI models

Energy Technology Data Exchange (ETDEWEB)

Brax, Philippe [Institut de Physique Théorique, CEA, IPhT, CNRS, URA2306, F-91191 Gif-sur-Yvette cédex (France); Burrage, Clare [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Davis, Anne-Christine, E-mail: Philippe.Brax@cea.fr, E-mail: Clare.Burrage@nottingham.ac.uk, E-mail: A.C.Davis@damtp.cam.ac.uk [Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, Cambridge CB3 0WA (United Kingdom)

2013-01-01

New fifth forces have not yet been detected in the laboratory or in the solar system, hence it is typically difficult to introduce new light scalar fields that would mediate such forces. In recent years it has been shown that a number of non-linear scalar field theories allow for a dynamical mechanism, such as the Vainshtein and chameleon ones, that suppresses the strength of the scalar fifth force in experimental environments. This is known as screening, however it is unclear how common screening is within non-linear scalar field theories. k-essence models are commonly studied examples of non-linear models, with DBI as the best motivated example, and so we ask whether these non-linearities are able to screen a scalar fifth force. We find that a Vainshtein-like screening mechanism exists for such models although with limited applicability. For instance, we cannot find a screening mechanism for DBI models. On the other hand, we construct a large class of k-essence models which lead to the acceleration of the Universe in the recent past for which the fifth force mediated by the scalar can be screened.

Variable screening and ranking using sampling-based sensitivity measures

International Nuclear Information System (INIS)

Wu, Y-T.; Mohanty, Sitakanta

2006-01-01

This paper presents a methodology for screening insignificant random variables and ranking significant important random variables using sensitivity measures including two cumulative distribution function (CDF)-based and two mean-response based measures. The methodology features (1) using random samples to compute sensitivities and (2) using acceptance limits, derived from the test-of-hypothesis, to classify significant and insignificant random variables. Because no approximation is needed in either the form of the performance functions or the type of continuous distribution functions representing input variables, the sampling-based approach can handle highly nonlinear functions with non-normal variables. The main characteristics and effectiveness of the sampling-based sensitivity measures are investigated using both simple and complex examples. Because the number of samples needed does not depend on the number of variables, the methodology appears to be particularly suitable for problems with large, complex models that have large numbers of random variables but relatively few numbers of significant random variables

Opportunistic testing versus organized prostate-specific antigen screening: outcome after 18 years in the Göteborg randomized population-based prostate cancer screening trial.

Science.gov (United States)

Arnsrud Godtman, Rebecka; Holmberg, Erik; Lilja, Hans; Stranne, Johan; Hugosson, Jonas

2015-09-01

It has been shown that organized screening decreases prostate cancer (PC) mortality, but the effect of opportunistic screening is largely unknown. To compare the ability to reduce PC mortality and the risk of overdiagnosis between organized and opportunistic screening. The Göteborg screening study invited 10 000 randomly selected men for prostate-specific antigen (PSA) testing every 2 yr since 1995, with a prostate biopsy recommended for men with PSA ≥2.5 ng/ml. The control group of 10 000 men not invited has been exposed to a previously reported increased rate of opportunistic PSA testing. Both groups were followed until December 31, 2012. Observed cumulative PC incidence and mortality rates in both groups were calculated using the actuarial method. Using historical data from 1990-1994 (pre-PSA era), we calculated expected PC incidence and mortality rates in the absence of any PSA testing. The number needed to invite (NNI) and the number needed to diagnose (NND) were calculated by comparing the expected versus observed incidence and mortality rates. At 18 yr, 1396 men were diagnosed with PC and 79 men died of PC in the screening group, compared to 962 and 122, respectively, in the control group. In the screening group, the observed cumulative PC incidence/mortality was 16%/0.98% compared to expected values of 6.8%/1.7%. The corresponding values for the control group were 11%/1.5% and 6.9%/1.7%. Organized screening was associated with an absolute PC-specific mortality reduction of 0.72% (95% confidence interval [CI] 0.50-0.94%) and relative risk reduction of 42% (95% CI 28-54%). There was an absolute reduction in PC deaths of 0.20% (95% CI -0.06% to 0.47%) and a relative risk reduction of 12% (95% CI -5 to 26%) associated with opportunistic PSA testing. NNI and NND were 139 (95% CI 107-200) and 13 for organized biennial screening and 493 (95% CI 213- -1563) and 23 for opportunistic screening. The extent of opportunistic screening could not be measured

Patterns and predictors of repeat fecal immunochemical and occult blood test screening in four large health care systems in the United States.

Science.gov (United States)

Singal, Amit G; Corley, Douglas A; Kamineni, Aruna; Garcia, Michael; Zheng, Yingye; Doria-Rose, Paul V; Quinn, Virginia P; Jensen, Christopher D; Chubak, Jessica; Tiro, Jasmin; Doubeni, Chyke A; Ghai, Nirupa R; Skinner, Celette Sugg; Wernli, Karen; Halm, Ethan A

2018-02-27

Effectiveness of fecal occult blood test (FOBT) for colorectal cancer (CRC) screening depends on annual testing, but little is known about patterns of repeat stool-based screening within different settings. Our study's objective was to characterize screening patterns and identify factors associated with repeat screening among patients who completed an index guaiac FOBT (gFOBT) or fecal immunochemical test (FIT). We performed a multi-center retrospective cohort study among people who completed a FOBT between January 2010 and December 2011 to characterize repeat screening patterns over the subsequent 3 years. We studied at 4 large health care delivery systems in the United States. Logistic regression analyses were used to identify factors associated with repeat screening patterns. We included individuals aged 50-71 years who completed an index FOBT and had at least 3 years of follow-up. We excluded people with a history of CRC, colonoscopy within 10 years or flexible sigmoidoscopy within 5 years before the index test, or positive index stool test. Consistent screening was defined as repeat FOBT within every 15 months and inconsistent screening as repeat testing at least once during follow-up but less than consistent screening. Among 959,857 eligible patients who completed an index FIT or gFOBT, 344,103 had three years of follow-up and met inclusion criteria. Of these, 46.6% had consistent screening, 43.4% inconsistent screening, and 10% had no repeat screening during follow-up. Screening patterns varied substantially across healthcare systems, with consistent screening proportions ranging from 1 to 54.3% and no repeat screening proportions ranging from 6.9 to 42.8%. Higher consistent screening proportions were observed in health systems with screening outreach and in-reach programs, whereas the safety-net health system, which uses opportunistic clinic-based screening, had the lowest consistent screening. Consistent screening increased with older age but was less

Dana-Farber Cancer Institute (DFCI): Computational Correction of Copy-number Effect in CRISPR-Cas9 Essentiality Screens of Cancer Cells | Office of Cancer Genomics

Science.gov (United States)

Genome-wide CRISPR-Cas9 screens were performed in 341 cell lines. The results were processed with the CERES algorithm to produce copy-number and guide-efficacy corrected gene knockout effect estimates.

A modified large number theory with constant G

Science.gov (United States)

Recami, Erasmo

1983-03-01

The inspiring “numerology” uncovered by Dirac, Eddington, Weyl, et al. can be explained and derived when it is slightly modified so to connect the “gravitational world” (cosmos) with the “strong world” (hadron), rather than with the electromagnetic one. The aim of this note is to show the following. In the present approach to the “Large Number Theory,” cosmos and hadrons are considered to be (finite) similar systems, so that the ratio{{bar R} / {{bar R} {bar r}} of the cosmos typical lengthbar R to the hadron typical lengthbar r is constant in time (for instance, if both cosmos and hadrons undergo an expansion/contraction cycle—according to the “cyclical bigbang” hypothesis—thenbar R andbar r can be chosen to be the maximum radii, or the average radii). As a consequence, then gravitational constant G results to be independent of time. The present note is based on work done in collaboration with P. Caldirola, G. D. Maccarrone, and M. Pavšič.

The challenge for genetic epidemiologists: how to analyze large numbers of SNPs in relation to complex diseases.

Science.gov (United States)

Heidema, A Geert; Boer, Jolanda M A; Nagelkerke, Nico; Mariman, Edwin C M; van der A, Daphne L; Feskens, Edith J M

2006-04-21

Genetic epidemiologists have taken the challenge to identify genetic polymorphisms involved in the development of diseases. Many have collected data on large numbers of genetic markers but are not familiar with available methods to assess their association with complex diseases. Statistical methods have been developed for analyzing the relation between large numbers of genetic and environmental predictors to disease or disease-related variables in genetic association studies. In this commentary we discuss logistic regression analysis, neural networks, including the parameter decreasing method (PDM) and genetic programming optimized neural networks (GPNN) and several non-parametric methods, which include the set association approach, combinatorial partitioning method (CPM), restricted partitioning method (RPM), multifactor dimensionality reduction (MDR) method and the random forests approach. The relative strengths and weaknesses of these methods are highlighted. Logistic regression and neural networks can handle only a limited number of predictor variables, depending on the number of observations in the dataset. Therefore, they are less useful than the non-parametric methods to approach association studies with large numbers of predictor variables. GPNN on the other hand may be a useful approach to select and model important predictors, but its performance to select the important effects in the presence of large numbers of predictors needs to be examined. Both the set association approach and random forests approach are able to handle a large number of predictors and are useful in reducing these predictors to a subset of predictors with an important contribution to disease. The combinatorial methods give more insight in combination patterns for sets of genetic and/or environmental predictor variables that may be related to the outcome variable. As the non-parametric methods have different strengths and weaknesses we conclude that to approach genetic association

Surface Microbiology of Smartphone Screen Protectors Among Healthcare Professionals.

Science.gov (United States)

Raza, Ibrahim; Raza, Awais; Razaa, Syed Ahmad; Sadar, Ahmad Bani; Qureshi, Ahmad Uzair; Talib, Usama; Chi, Gerald

2017-12-26

The use of smartphones with touch screens has become a norm for healthcare professionals (HCP). The risk of smart screen contamination has been proven, and guidelines are available to deal with possible contamination. A large number of smartphone users apply plastic or glass screen protectors onto their mobile phone screens to prevent scratches. However, these materials are not scratch proof, and their antipathogenic properties have not been studied. We have conducted a study to determine the frequency of smartphone screen protector contamination and compared the data with contamination on the bare area on the same mobile screens. The sample size included only HCPs working in acute care settings and having at least eight hours of exposure time every day. A total of 64 samples were collected, which reported 62.5% (n = 40/64) positive culture swabs from the protected areas of the screen and 45.3% (n = 29/64) from the unprotected area of the screen. Micrococcus and Gram-negative rods grew only on samples taken from the protected area whereas the bare area showed no such growth. There was no statistically significant difference in the frequency based on smart screen size, duration of use during duty hours, or the setting where it was used. Smartphone screen protectors from healthcare providers may harbor pathogenic bacteria, especially in acute care settings. Coagulase-negative Staphylococci followed by Bacillus species were the most commonly yielded bacteria among house officers and postgraduate trainees in the present study.

Mammography screening in Greece: An exploratory survey of women's views, experiences and behaviours

Directory of Open Access Journals (Sweden)

Athena Kalokerinou

2012-01-01

Full Text Available Background: Internationally, breast cancer comprises 29% of all cancer incidences. In Greece, 1,500-1,800women die annually from breast cancer out of the 4,000 who are affected. Only 5% are detected at an early diseasestage through mammography screening.Aim: This paper presents findings from a study exploring the factors that influence Greek women’smammography screening behaviour.Methodology: Data were collected in Athens-Greece, during the period March-July 2008, from individuals whowere members of six women’s associations. One hundred and eighty six questionnaires were completed and 33interviews were conducted from a sub-sample. This paper reports the findings from the questionnaire survey.Results: Participants had a variety of demographic characteristics with 85% of them having attendedmammography screening. Only 61% of them intended to continue in the future. Τhe majority of women agreedwith a number of factors which supported their decision to participate in regular mammography screening, such asdoctors’ encouragement and mammogram efficacy to detect breast cancer at an early stage, while anxiety wasidentified as a possible inhibitor to their participation.Conclusion: Women’s mammography screening behaviour and perceptions of mammography screening appearedto be positive in relation to their participation. However, the reasons as to why a large number of women indicatedthey were unlikely to go for mammography screening again is not known, and needs further investigation.

Evaluating usability of the Halden Reactor Large Screen Display. Is the Information Rich Design concept suitable for real-world installations?

International Nuclear Information System (INIS)

Braseth, Alf Ove

2013-01-01

Large Screen Displays (LSDs) are beginning to supplement desktop displays in modern control rooms, having the potential to display the big picture of complex processes. Information Rich Design (IRD) is a LSD concept used in many real-life installations in the petroleum domain, and more recently in nuclear research applications. The objectives of IRD are to provide the big picture, avoiding keyhole related problems while supporting fast visual perception of larger data sets. Two LSDs based on the IRD concept have been developed for large-scale nuclear simulators for research purposes; they have however suffered from unsatisfying user experience. The new Halden Reactor LSD, used to monitor a nuclear research reactor, was designed according to recent proposed Design Principles compiled in this paper to mitigate previously experienced problems. This paper evaluates the usability of the Halden Reactor LSD, comparing usability data with the replaced analogue panel, and data for an older IRD large screen display. The results suggest that the IRD concept is suitable for use in real-life applications from a user experience point of view, and that the recently proposed Design Principles have had a positive effect on usability. (author)

Vicious random walkers in the limit of a large number of walkers

International Nuclear Information System (INIS)

Forrester, P.J.

1989-01-01

The vicious random walker problem on a line is studied in the limit of a large number of walkers. The multidimensional integral representing the probability that the p walkers will survive a time t (denoted P t (p) ) is shown to be analogous to the partition function of a particular one-component Coulomb gas. By assuming the existence of the thermodynamic limit for the Coulomb gas, one can deduce asymptotic formulas for P t (p) in the large-p, large-t limit. A straightforward analysis gives rigorous asymptotic formulas for the probability that after a time t the walkers are in their initial configuration (this event is termed a reunion). Consequently, asymptotic formulas for the conditional probability of a reunion, given that all walkers survive, are derived. Also, an asymptotic formula for the conditional probability density that any walker will arrive at a particular point in time t, given that all p walkers survive, is calculated in the limit t >> p

Benefit and risk in breast screening

International Nuclear Information System (INIS)

Law, J.; Faulkner, K.; Neilson, F.

2001-01-01

Justification of breast screening in radiation protection terms both for the screened population and on an individual basis is necessary. In this paper the number of cancers detected, and the number of cancers potentially induced by radiation in the UK National Health Service Breast Screening Programme (NHS BSP) are compared. Detection rates reported up to 1998 are used, with x-ray doses for 1997 and 1998 and breast cancer induction risk factors, stratified by age, recommended by the National Radiological Protection Board in 1994. Cancers detected exceed those potentially induced at all ages from 50-64. The relationship between these cancer numbers and the associated benefit and risk, in terms of breast cancer deaths avoided and induced, is then investigated. Improved values of the Nottingham Prognostic Indicator (NPI) attributed to screening provide one means of doing this. Using this strict criterion the breast-screening programme is also justified in radiation protection terms. (author)

The use of graph theory in the sensitivity analysis of the model output: a second order screening method

International Nuclear Information System (INIS)

Campolongo, Francesca; Braddock, Roger

1999-01-01

Sensitivity analysis screening methods aim to isolate the most important factors in experiments involving a large number of significant factors and interactions. This paper extends the one-factor-at-a-time screening method proposed by Morris. The new method, in addition to the 'overall' sensitivity measures already provided by the traditional Morris method, offers estimates of the two-factor interaction effects. The number of model evaluations required is O(k 2 ), where k is the number of model input factors. The efficient sampling strategy in the parameter space is based on concepts of graph theory and on the solution of the 'handcuffed prisoner problem'

iScreen: Image-Based High-Content RNAi Screening Analysis Tools.

Science.gov (United States)

Zhong, Rui; Dong, Xiaonan; Levine, Beth; Xie, Yang; Xiao, Guanghua

2015-09-01

High-throughput RNA interference (RNAi) screening has opened up a path to investigating functional genomics in a genome-wide pattern. However, such studies are often restricted to assays that have a single readout format. Recently, advanced image technologies have been coupled with high-throughput RNAi screening to develop high-content screening, in which one or more cell image(s), instead of a single readout, were generated from each well. This image-based high-content screening technology has led to genome-wide functional annotation in a wider spectrum of biological research studies, as well as in drug and target discovery, so that complex cellular phenotypes can be measured in a multiparametric format. Despite these advances, data analysis and visualization tools are still largely lacking for these types of experiments. Therefore, we developed iScreen (image-Based High-content RNAi Screening Analysis Tool), an R package for the statistical modeling and visualization of image-based high-content RNAi screening. Two case studies were used to demonstrate the capability and efficiency of the iScreen package. iScreen is available for download on CRAN (http://cran.cnr.berkeley.edu/web/packages/iScreen/index.html). The user manual is also available as a supplementary document. © 2014 Society for Laboratory Automation and Screening.

System for high-voltage control detectors with large number photomultipliers

International Nuclear Information System (INIS)

Donskov, S.V.; Kachanov, V.A.; Mikhajlov, Yu.V.

1985-01-01

A simple and inexpensive on-line system for hihg-voltage control which is designed for detectors with a large number of photomultipliers is developed and manufactured. It has been developed for the GAMC type hodoscopic electromagnetic calorimeters, comprising up to 4 thousand photomultipliers. High voltage variation is performed by a high-speed potentiometer which is rotated by a microengine. Block-diagrams of computer control electronics are presented. The high-voltage control system has been used for five years in the IHEP and CERN accelerator experiments. The operation experience has shown that it is quite simple and convenient in operation. In case of about 6 thousand controlled channels in both experiments no potentiometer and microengines failures were observed

Sociocultural barriers to cervical screening in South Auckland, New Zealand.

Science.gov (United States)

Lovell, Sarah; Kearns, Robin A; Friesen, Wardlow

2007-07-01

Cervical screening has been subject to intense media scrutiny in New Zealand in recent years prompted by a series of health system failings through which a number of women developed cervical cancer despite undergoing regular smears. This paper considers why underscreening persists in a country where cervical screening has a high profile. It explores how the promotion of cervical screening has impacted on the decisions of women to undergo a smear test. Ideas of risk and the new public health are deployed to develop a context for thinking about screening as a form of governing the body. Qualitative interviews with 17 women who were overdue for a cervical smear were undertaken in 2001-2002, yielding understandings of their knowledge of screening and their reasons for postponement. Nine providers of screening services were also interviewed. Concurrent with socioeconomic limitations, concerns over exposing one's body loomed large in women's reasons for delaying being screened. In particular, feelings of shyness and embarrassment were encountered among Maori and Pacific women for whom exposing bodies in the process of smear taking compromises cultural beliefs about sacredness. We conclude that medicalization of the body has, paradoxically, assisted many women in dealing with the intrusion of screening. For others, compliance with the exhortations to be screened brings a high emotional and cultural cost which should at least be considered in health policy debates.

The fluorescence theatre: a cost-effective device using theatre gels for fluorescent protein and dye screening.

Science.gov (United States)

Heil, John R; Nordeste, Ricardo F; Charles, Trevor C

2011-04-01

Here we report a simple cost-effective device for screening colonies on plates for expression of the monomeric red fluorescent protein mRFP1 and the fluorescent dye Nile red. This device can be built from any simple light source, in our case a Quebec Colony Counter, and cost-effective theatre gels. The device can be assembled in as little as 20 min, and it produces excellent results when screening a large number of colonies.

Organisational aspects of mammography screening in digital settings: First experiences of Luxembourg

International Nuclear Information System (INIS)

Shannoun, F.; Schanck, J. M.; Scharpantgen, A.; Wagnon, M. C.; Ben Daoud, M.; Back, C.

2008-01-01

Luxembourg has been conducting a breast cancer screening programme since 1992, like a large number of other European countries, as early detection and treatment of breast cancer have been proven to reduce mortality. The majority of these screening programmes are based on analogue X-ray technology and have optimised their organisation of transporting, archiving and reading with respect to films. Last decade is marked by enormous developments in digital mammography. Different technologies such as flat panel-, computed radiography- and scanning systems became available. Digital mammography is expected to have a major impact on quality and organisation of breast cancer screening programmes. Screening programmes are now faced with a huge challenge of incorporating the digital technology, including implementation of electronic image exchange, conception of new electronic work-flow, establishing adapted quality assurance programmes and training of radiologists and technical personnel. Initial experiences of the Luxembourg approach in organising digital mammography screening and its quality assurance are reported. (authors)

Analysis and hit filtering of a very large library of compounds screened against Mycobacterium tuberculosis.

Science.gov (United States)

Ekins, Sean; Kaneko, Takushi; Lipinski, Christopher A; Bradford, Justin; Dole, Krishna; Spektor, Anna; Gregory, Kellan; Blondeau, David; Ernst, Sylvia; Yang, Jeremy; Goncharoff, Nicko; Hohman, Moses M; Bunin, Barry A

2010-11-01

There is an urgent need for new drugs against tuberculosis which annually claims 1.7-1.8 million lives. One approach to identify potential leads is to screen in vitro small molecules against Mycobacterium tuberculosis (Mtb). Until recently there was no central repository to collect information on compounds screened. Consequently, it has been difficult to analyze molecular properties of compounds that inhibit the growth of Mtb in vitro. We have collected data from publically available sources on over 300 000 small molecules deposited in the Collaborative Drug Discovery TB Database. A cheminformatics analysis on these compounds indicates that inhibitors of the growth of Mtb have statistically higher mean logP, rule of 5 alerts, while also having lower HBD count, atom count and lower PSA (ChemAxon descriptors), compared to compounds that are classed as inactive. Additionally, Bayesian models for selecting Mtb active compounds were evaluated with over 100 000 compounds and, they demonstrated 10 fold enrichment over random for the top ranked 600 compounds. This represents a promising approach for finding compounds active against Mtb in whole cells screened under the same in vitro conditions. Various sets of Mtb hit molecules were also examined by various filtering rules used widely in the pharmaceutical industry to identify compounds with potentially reactive moieties. We found differences between the number of compounds flagged by these rules in Mtb datasets, malaria hits, FDA approved drugs and antibiotics. Combining these approaches may enable selection of compounds with increased probability of inhibition of whole cell Mtb activity.

Numerical and analytical approaches to an advection-diffusion problem at small Reynolds number and large Péclet number

Science.gov (United States)

Fuller, Nathaniel J.; Licata, Nicholas A.

2018-05-01

Obtaining a detailed understanding of the physical interactions between a cell and its environment often requires information about the flow of fluid surrounding the cell. Cells must be able to effectively absorb and discard material in order to survive. Strategies for nutrient acquisition and toxin disposal, which have been evolutionarily selected for their efficacy, should reflect knowledge of the physics underlying this mass transport problem. Motivated by these considerations, in this paper we discuss the results from an undergraduate research project on the advection-diffusion equation at small Reynolds number and large Péclet number. In particular, we consider the problem of mass transport for a Stokesian spherical swimmer. We approach the problem numerically and analytically through a rescaling of the concentration boundary layer. A biophysically motivated first-passage problem for the absorption of material by the swimming cell demonstrates quantitative agreement between the numerical and analytical approaches. We conclude by discussing the connections between our results and the design of smart toxin disposal systems.

Semiautomated radioimmunoassay for mass screening of drugs of abuse

International Nuclear Information System (INIS)

Sulkowski, T.S.; Lathrop, G.D.; Merritt, J.H.; Landez, J.H.; Noe, E.R.

1975-01-01

A rapid, semiautomated radioimmunoassay system for detection of morphine, barbiturates, and amphetamines is described. The assays are applicable to large drug abuse screening programs. The heart of the system is the automatic pipetting station which can accomplish 600 pipetting operations per hour. The method uses 15 to 30 μl for the amphetamine and combined morphine/barbiturate assays. A number of other drugs were tested for interference with the assays and the results are discussed

Automatic detection of retinal anatomy to assist diabetic retinopathy screening

Science.gov (United States)

Fleming, Alan D.; Goatman, Keith A.; Philip, Sam; Olson, John A.; Sharp, Peter F.

2007-01-01

Screening programmes for diabetic retinopathy are being introduced in the United Kingdom and elsewhere. These require large numbers of retinal images to be manually graded for the presence of disease. Automation of image grading would have a number of benefits. However, an important prerequisite for automation is the accurate location of the main anatomical features in the image, notably the optic disc and the fovea. The locations of these features are necessary so that lesion significance, image field of view and image clarity can be assessed. This paper describes methods for the robust location of the optic disc and fovea. The elliptical form of the major retinal blood vessels is used to obtain approximate locations, which are refined based on the circular edge of the optic disc and the local darkening at the fovea. The methods have been tested on 1056 sequential images from a retinal screening programme. Positional accuracy was better than 0.5 of a disc diameter in 98.4% of cases for optic disc location, and in 96.5% of cases for fovea location. The methods are sufficiently accurate to form an important and effective component of an automated image grading system for diabetic retinopathy screening.

Automatic detection of retinal anatomy to assist diabetic retinopathy screening

Energy Technology Data Exchange (ETDEWEB)

Fleming, Alan D [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom); Goatman, Keith A [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom); Philip, Sam [Grampian Diabetes Retinal Screening Programme, Woolmanhill Hospital, Aberdeen, AB25 1LD (United Kingdom); Olson, John A [Grampian Diabetes Retinal Screening Programme, Woolmanhill Hospital, Aberdeen, AB25 1LD (United Kingdom); Sharp, Peter F [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom)

2007-01-21

Screening programmes for diabetic retinopathy are being introduced in the United Kingdom and elsewhere. These require large numbers of retinal images to be manually graded for the presence of disease. Automation of image grading would have a number of benefits. However, an important prerequisite for automation is the accurate location of the main anatomical features in the image, notably the optic disc and the fovea. The locations of these features are necessary so that lesion significance, image field of view and image clarity can be assessed. This paper describes methods for the robust location of the optic disc and fovea. The elliptical form of the major retinal blood vessels is used to obtain approximate locations, which are refined based on the circular edge of the optic disc and the local darkening at the fovea. The methods have been tested on 1056 sequential images from a retinal screening programme. Positional accuracy was better than 0.5 of a disc diameter in 98.4% of cases for optic disc location, and in 96.5% of cases for fovea location. The methods are sufficiently accurate to form an important and effective component of an automated image grading system for diabetic retinopathy screening.

Automatic detection of retinal anatomy to assist diabetic retinopathy screening

International Nuclear Information System (INIS)

Fleming, Alan D; Goatman, Keith A; Philip, Sam; Olson, John A; Sharp, Peter F

2007-01-01

Screening programmes for diabetic retinopathy are being introduced in the United Kingdom and elsewhere. These require large numbers of retinal images to be manually graded for the presence of disease. Automation of image grading would have a number of benefits. However, an important prerequisite for automation is the accurate location of the main anatomical features in the image, notably the optic disc and the fovea. The locations of these features are necessary so that lesion significance, image field of view and image clarity can be assessed. This paper describes methods for the robust location of the optic disc and fovea. The elliptical form of the major retinal blood vessels is used to obtain approximate locations, which are refined based on the circular edge of the optic disc and the local darkening at the fovea. The methods have been tested on 1056 sequential images from a retinal screening programme. Positional accuracy was better than 0.5 of a disc diameter in 98.4% of cases for optic disc location, and in 96.5% of cases for fovea location. The methods are sufficiently accurate to form an important and effective component of an automated image grading system for diabetic retinopathy screening

Automatic detection of retinal anatomy to assist diabetic retinopathy screening.

Science.gov (United States)

Fleming, Alan D; Goatman, Keith A; Philip, Sam; Olson, John A; Sharp, Peter F

2007-01-21

Screening programmes for diabetic retinopathy are being introduced in the United Kingdom and elsewhere. These require large numbers of retinal images to be manually graded for the presence of disease. Automation of image grading would have a number of benefits. However, an important prerequisite for automation is the accurate location of the main anatomical features in the image, notably the optic disc and the fovea. The locations of these features are necessary so that lesion significance, image field of view and image clarity can be assessed. This paper describes methods for the robust location of the optic disc and fovea. The elliptical form of the major retinal blood vessels is used to obtain approximate locations, which are refined based on the circular edge of the optic disc and the local darkening at the fovea. The methods have been tested on 1056 sequential images from a retinal screening programme. Positional accuracy was better than 0.5 of a disc diameter in 98.4% of cases for optic disc location, and in 96.5% of cases for fovea location. The methods are sufficiently accurate to form an important and effective component of an automated image grading system for diabetic retinopathy screening.

A simple screening method for detection of Klinefelter syndrome and other X-chromosome aneuploidies based on copy number of the androgen receptor gene

DEFF Research Database (Denmark)

Ottesen, A M; Garn, I D; Aksglaede, L

2007-01-01

Due to the high prevalence and variable phenotype of patients with Klinefelter syndrome, there is a need for a robust and rapid screening method allowing early diagnosis. Here, we report on the development and detailed clinical validation of a quantitative real-time PCR (qPCR)-based method...... of the copy number assessment of the androgen receptor (AR) gene, located to Xq11.2-q12. We analysed samples from 50 individuals, including a healthy male and female controls and patients with Klinefelter syndrome (47,XXY; 48,XXXY) (n = 28), mosaicisms (46,XX/47,XXY/48XXYY; 45,X/46,XY) (n = 3), other sex......-gene expression. The XIST-expression based assay was correct in only 29/36 samples (81%). Our findings demonstrated that the AR-qPCR technique is a simple and reliable screening method for diagnosis of patients with Klinefelter syndrome or other chromosomal disorders involving an aberrant number of X-chromosomes....

Tracking of large-scale structures in turbulent channel with direct numerical simulation of low Prandtl number passive scalar

Science.gov (United States)

Tiselj, Iztok

2014-12-01

Channel flow DNS (Direct Numerical Simulation) at friction Reynolds number 180 and with passive scalars of Prandtl numbers 1 and 0.01 was performed in various computational domains. The "normal" size domain was ˜2300 wall units long and ˜750 wall units wide; size taken from the similar DNS of Moser et al. The "large" computational domain, which is supposed to be sufficient to describe the largest structures of the turbulent flows was 3 times longer and 3 times wider than the "normal" domain. The "very large" domain was 6 times longer and 6 times wider than the "normal" domain. All simulations were performed with the same spatial and temporal resolution. Comparison of the standard and large computational domains shows the velocity field statistics (mean velocity, root-mean-square (RMS) fluctuations, and turbulent Reynolds stresses) that are within 1%-2%. Similar agreement is observed for Pr = 1 temperature fields and can be observed also for the mean temperature profiles at Pr = 0.01. These differences can be attributed to the statistical uncertainties of the DNS. However, second-order moments, i.e., RMS temperature fluctuations of standard and large computational domains at Pr = 0.01 show significant differences of up to 20%. Stronger temperature fluctuations in the "large" and "very large" domains confirm the existence of the large-scale structures. Their influence is more or less invisible in the main velocity field statistics or in the statistics of the temperature fields at Prandtl numbers around 1. However, these structures play visible role in the temperature fluctuations at low Prandtl number, where high temperature diffusivity effectively smears the small-scale structures in the thermal field and enhances the relative contribution of large-scales. These large thermal structures represent some kind of an echo of the large scale velocity structures: the highest temperature-velocity correlations are not observed between the instantaneous temperatures and

Do neutron stars disprove multiplicative creation in Dirac's large number hypothesis

International Nuclear Information System (INIS)

Qadir, A.; Mufti, A.A.

1980-07-01

Dirac's cosmology, based on his large number hypothesis, took the gravitational coupling to be decreasing with time and matter to be created as the square of time. Since the effects predicted by Dirac's theory are very small, it is difficult to find a ''clean'' test for it. Here we show that the observed radiation from pulsars is inconsistent with Dirac's multiplicative creation model, in which the matter created is proportional to the density of matter already present. Of course, this discussion makes no comment on the ''additive creation'' model, or on the revised version of Dirac's theory. (author)

Automated flow cytometric analysis across large numbers of samples and cell types.

Science.gov (United States)

Chen, Xiaoyi; Hasan, Milena; Libri, Valentina; Urrutia, Alejandra; Beitz, Benoît; Rouilly, Vincent; Duffy, Darragh; Patin, Étienne; Chalmond, Bernard; Rogge, Lars; Quintana-Murci, Lluis; Albert, Matthew L; Schwikowski, Benno

2015-04-01

Multi-parametric flow cytometry is a key technology for characterization of immune cell phenotypes. However, robust high-dimensional post-analytic strategies for automated data analysis in large numbers of donors are still lacking. Here, we report a computational pipeline, called FlowGM, which minimizes operator input, is insensitive to compensation settings, and can be adapted to different analytic panels. A Gaussian Mixture Model (GMM)-based approach was utilized for initial clustering, with the number of clusters determined using Bayesian Information Criterion. Meta-clustering in a reference donor permitted automated identification of 24 cell types across four panels. Cluster labels were integrated into FCS files, thus permitting comparisons to manual gating. Cell numbers and coefficient of variation (CV) were similar between FlowGM and conventional gating for lymphocyte populations, but notably FlowGM provided improved discrimination of "hard-to-gate" monocyte and dendritic cell (DC) subsets. FlowGM thus provides rapid high-dimensional analysis of cell phenotypes and is amenable to cohort studies. Copyright © 2015. Published by Elsevier Inc.

How to benchmark methods for structure-based virtual screening of large compound libraries.

Science.gov (United States)

Christofferson, Andrew J; Huang, Niu

2012-01-01

Structure-based virtual screening is a useful computational technique for ligand discovery. To systematically evaluate different docking approaches, it is important to have a consistent benchmarking protocol that is both relevant and unbiased. Here, we describe the designing of a benchmarking data set for docking screen assessment, a standard docking screening process, and the analysis and presentation of the enrichment of annotated ligands among a background decoy database.

A methodology for the synthesis of heat exchanger networks having large numbers of uncertain parameters

International Nuclear Information System (INIS)

Novak Pintarič, Zorka; Kravanja, Zdravko

2015-01-01

This paper presents a robust computational methodology for the synthesis and design of flexible HEN (Heat Exchanger Networks) having large numbers of uncertain parameters. This methodology combines several heuristic methods which progressively lead to a flexible HEN design at a specific level of confidence. During the first step, a HEN topology is generated under nominal conditions followed by determining those points critical for flexibility. A significantly reduced multi-scenario model for flexible HEN design is formulated at the nominal point with the flexibility constraints at the critical points. The optimal design obtained is tested by stochastic Monte Carlo optimization and the flexibility index through solving one-scenario problems within a loop. This presented methodology is novel regarding the enormous reduction of scenarios in HEN design problems, and computational effort. Despite several simplifications, the capability of designing flexible HENs with large numbers of uncertain parameters, which are typical throughout industry, is not compromised. An illustrative case study is presented for flexible HEN synthesis comprising 42 uncertain parameters. - Highlights: • Methodology for HEN (Heat Exchanger Network) design under uncertainty is presented. • The main benefit is solving HENs having large numbers of uncertain parameters. • Drastically reduced multi-scenario HEN design problem is formulated through several steps. • Flexibility of HEN is guaranteed at a specific level of confidence.

Screen-Display-Induced Photoresponse Mapping for Large-Area Photovoltaics

DEFF Research Database (Denmark)

Gupta, Ritu; Kiruthika, S.; Rao, K. D. M.

2013-01-01

As solar cell modules are becoming larger, it is important to pay attention to defects originating from the fabrication process and degradation during operation in the ambient. In this article, a simple method of using computer screen display as a light source to map the photoresponse of the solar...

Large Scale Screening of Southern African Plant Extracts for the Green Synthesis of Gold Nanoparticles Using Microtitre-Plate Method

Directory of Open Access Journals (Sweden)

Abdulrahman M. Elbagory

2016-11-01

Full Text Available The preparation of gold nanoparticles (AuNPs involves a variety of chemical and physical methods. These methods use toxic and environmentally harmful chemicals. Consequently, the synthesis of AuNPs using green chemistry has been under investigation to develop eco-friendly nanoparticles. One approach to achieve this is the use of plant-derived phytochemicals that are capable of reducing gold ions to produce AuNPs. The aim of this study was to implement a facile microtitre-plate method to screen a large number of aqueous plant extracts to determine the optimum concentration (OC for the bio-synthesis of the AuNPs. Several AuNPs of different sizes and shapes were successfully synthesized and characterized from 17 South African plants. The characterization was done using Ultra Violet-Visible Spectroscopy, Dynamic Light Scattering, High Resolution Transmission Electron Microscopy and Energy-Dispersive X-ray Spectroscopy. We also studied the effects of temperature on the synthesis of the AuNPs and showed that changes in temperatures affect the size and dispersity of the generated AuNPs. We also evaluated the stability of the synthesized AuNPs and showed that some of them are stable in biological buffer solutions.

The large numbers hypothesis and the Einstein theory of gravitation

International Nuclear Information System (INIS)

Dirac, P.A.M.

1979-01-01

A study of the relations between large dimensionless numbers leads to the belief that G, expressed in atomic units, varies with the epoch while the Einstein theory requires G to be constant. These two requirements can be reconciled by supposing that the Einstein theory applies with a metric that differs from the atomic metric. The theory can be developed with conservation of mass by supposing that the continual increase in the mass of the observable universe arises from a continual slowing down of the velocity of recession of the galaxies. This leads to a model of the Universe that was first proposed by Einstein and de Sitter (the E.S. model). The observations of the microwave radiation fit in with this model. The static Schwarzchild metric has to be modified to fit in with the E.S. model for large r. The modification is worked out, and also the motion of planets with the new metric. It is found that there is a difference between ephemeris time and atomic time, and also that there should be an inward spiralling of the planets, referred to atomic units, superposed on the motion given by ordinary gravitational theory. These are effects that can be checked by observation, but there is no conclusive evidence up to the present. (author)

Hysterectomy and its impact on the calculated incidence of cervical cancer and screening coverage in Denmark

DEFF Research Database (Denmark)

Lam, Janni Uyen Hoa; Lynge, Elsebeth; Njor, Sisse Helle

2015-01-01

sense to determine the indicators also for the true at-risk populations. We described the frequency of total hysterectomy in Denmark and its impact on the calculated incidence of cervical cancer and the screening coverage. MATERIAL AND METHODS: With data from five Danish population-based registries......% (adjusted). In Denmark, hysterectomies do not have a large overall impact on the calculated cancer incidence and screening coverage. Nevertheless, at ≥ 65 years adjusted rates would increase by almost 20% compared to unadjusted rates. This suggests that calculating disease risks per organ-years may have......, the incidence rate of cervical cancer and the screening coverage for women aged 23-64 years on 31 December 2010 were calculated with and without adjustments for hysterectomies undertaken for reasons other than cervical cancer. They were calculated as the number of cases divided by 1) the total number of woman...

A large-scale RNA interference screen identifies genes that regulate autophagy at different stages.

Science.gov (United States)

Guo, Sujuan; Pridham, Kevin J; Virbasius, Ching-Man; He, Bin; Zhang, Liqing; Varmark, Hanne; Green, Michael R; Sheng, Zhi

2018-02-12

Dysregulated autophagy is central to the pathogenesis and therapeutic development of cancer. However, how autophagy is regulated in cancer is not well understood and genes that modulate cancer autophagy are not fully defined. To gain more insights into autophagy regulation in cancer, we performed a large-scale RNA interference screen in K562 human chronic myeloid leukemia cells using monodansylcadaverine staining, an autophagy-detecting approach equivalent to immunoblotting of the autophagy marker LC3B or fluorescence microscopy of GFP-LC3B. By coupling monodansylcadaverine staining with fluorescence-activated cell sorting, we successfully isolated autophagic K562 cells where we identified 336 short hairpin RNAs. After candidate validation using Cyto-ID fluorescence spectrophotometry, LC3B immunoblotting, and quantitative RT-PCR, 82 genes were identified as autophagy-regulating genes. 20 genes have been reported previously and the remaining 62 candidates are novel autophagy mediators. Bioinformatic analyses revealed that most candidate genes were involved in molecular pathways regulating autophagy, rather than directly participating in the autophagy process. Further autophagy flux assays revealed that 57 autophagy-regulating genes suppressed autophagy initiation, whereas 21 candidates promoted autophagy maturation. Our RNA interference screen identifies identified genes that regulate autophagy at different stages, which helps decode autophagy regulation in cancer and offers novel avenues to develop autophagy-related therapies for cancer.

Superposition of elliptic functions as solutions for a large number of nonlinear equations

International Nuclear Information System (INIS)

Khare, Avinash; Saxena, Avadh

2014-01-01

For a large number of nonlinear equations, both discrete and continuum, we demonstrate a kind of linear superposition. We show that whenever a nonlinear equation admits solutions in terms of both Jacobi elliptic functions cn(x, m) and dn(x, m) with modulus m, then it also admits solutions in terms of their sum as well as difference. We have checked this in the case of several nonlinear equations such as the nonlinear Schrödinger equation, MKdV, a mixed KdV-MKdV system, a mixed quadratic-cubic nonlinear Schrödinger equation, the Ablowitz-Ladik equation, the saturable nonlinear Schrödinger equation, λϕ 4 , the discrete MKdV as well as for several coupled field equations. Further, for a large number of nonlinear equations, we show that whenever a nonlinear equation admits a periodic solution in terms of dn 2 (x, m), it also admits solutions in terms of dn 2 (x,m)±√(m) cn (x,m) dn (x,m), even though cn(x, m)dn(x, m) is not a solution of these nonlinear equations. Finally, we also obtain superposed solutions of various forms for several coupled nonlinear equations

Sensitivity of neuroprogenitor cells to chemical-induced apoptosis using a multiplexed assay suitable for high-throughput screening*

Science.gov (United States)

AbstractHigh-throughput methods are useful for rapidly screening large numbers of chemicals for biological activity, including the perturbation of pathways that may lead to adverse cellular effects. In vitro assays for the key events of neurodevelopment, including apoptosis, may ...

Factors associated with performing tuberculosis screening of HIV-positive patients in Ghana: LASSO-based predictor selection in a large public health data set

Directory of Open Access Journals (Sweden)

Susanne Mueller-Using

2016-07-01

Full Text Available Abstract Background The purpose of this study is to propose the Least Absolute Shrinkage and Selection Operators procedure (LASSO as an alternative to conventional variable selection models, as it allows for easy interpretation and handles multicollinearities. We developed a model on the basis of LASSO-selected parameters in order to link associated demographical, socio-economical, clinical and immunological factors to performing tuberculosis screening in HIV-positive patients in Ghana. Methods Applying the LASSO method and multivariate logistic regression analysis on a large public health data set, we selected relevant predictors related to tuberculosis screening. Results One Thousand Ninety Five patients infected with HIV were enrolled into this study with 691 (63.2 % of them having tuberculosis screening documented in their patient folders. Predictors found to be significantly associated with performance of tuberculosis screening can be classified into factors related to the clinician’s perception of the clinical state, as well as those related to PLHIV’s awareness. These factors include newly diagnosed HIV infections (n = 354 (32.42 %, aOR 1.84, current CD4+ T cell count (aOR 0.92, non-availability of HIV type (n = 787 (72.07 %, aOR 0.56, chronic cough (n = 32 (2.93 %, aOR 5.07, intake of co-trimoxazole (n = 271 (24.82 %, aOR 2.31, vitamin supplementation (n = 220 (20.15 %, aOR 2.64 as well as the use of mosquito bed nets (n = 613 (56.14 %, aOR 1.53. Conclusions Accelerated TB screening among newly diagnosed HIV-patients indicates that application of the WHO screening form for intensifying tuberculosis case finding among HIV-positive individuals in resource-limited settings is increasingly adopted. However, screening for TB in PLHIV is still impacted by clinician’s perception of patient’s health state and PLHIV’s health awareness. Education of staff, counselling of PLHIV and sufficient financing are

Effectiveness of screening colonoscopy in reducing the risk of death from right and left colon cancer: a large community-based study.

Science.gov (United States)

Doubeni, Chyke A; Corley, Douglas A; Quinn, Virginia P; Jensen, Christopher D; Zauber, Ann G; Goodman, Michael; Johnson, Jill R; Mehta, Shivan J; Becerra, Tracy A; Zhao, Wei K; Schottinger, Joanne; Doria-Rose, V Paul; Levin, Theodore R; Weiss, Noel S; Fletcher, Robert H

2018-02-01

Screening colonoscopy's effectiveness in reducing colorectal cancer mortality risk in community populations is unclear, particularly for right-colon cancers, leading to recommendations against its use for screening in some countries. This study aimed to determine whether, among average-risk people, receipt of screening colonoscopy reduces the risk of dying from both right-colon and left-colon/rectal cancers. We conducted a nested case-control study with incidence-density matching in screening-eligible Kaiser Permanente members. Patients who were 55-90 years old on their colorectal cancer death date during 2006-2012 were matched on diagnosis (reference) date to controls on age, sex, health plan enrolment duration and geographical region. We excluded patients at increased colorectal cancer risk, or with prior colorectal cancer diagnosis or colectomy. The association between screening colonoscopy receipt in the 10-year period before the reference date and colorectal cancer death risk was evaluated while accounting for other screening exposures. We analysed 1747 patients who died from colorectal cancer and 3460 colorectal cancer-free controls. Compared with no endoscopic screening, receipt of a screening colonoscopy was associated with a 67% reduction in the risk of death from any colorectal cancer (adjusted OR (aOR)=0.33, 95% CI 0.21 to 0.52). By cancer location, screening colonoscopy was associated with a 65% reduction in risk of death for right-colon cancers (aOR=0.35, CI 0.18 to 0.65) and a 75% reduction for left-colon/rectal cancers (aOR=0.25, CI 0.12 to 0.53). Screening colonoscopy was associated with a substantial and comparably decreased mortality risk for both right-sided and left-sided cancers within a large community-based population. 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/.

Designing a diverse high-quality library for crystallography-based FBDD screening.

Science.gov (United States)

Tounge, Brett A; Parker, Michael H

2011-01-01

A well-chosen set of fragments is able to cover a large chemical space using a small number of compounds. The actual size and makeup of the fragment set is dependent on the screening method since each technique has its own practical limits in terms of the number of compounds that can be screened and requirements for compound solubility. In this chapter, an overview of the general requirements for a fragment library is presented for different screening platforms. In the case of the FBDD work at Johnson & Johnson Pharmaceutical Research and Development, L.L.C., our main screening technology is X-ray crystallography. Since every soaked protein crystal needs to be diffracted and a protein structure determined to delineate if a fragment binds, the size of our initial screening library cannot be a rate-limiting factor. For this reason, we have chosen 900 as the appropriate primary fragment library size. To choose the best set, we have developed our own mix of simple property ("Rule of 3") and "bad" substructure filtering. While this gets one a long way in terms of limiting the fragment pool, there are still tens of thousands of compounds to choose from after this initial step. Many of the choices left at this stage are not drug-like, so we have developed an FBDD Score to help select a 900-compound set. The details of this score and the filtering are presented. Copyright © 2011 Elsevier Inc. All rights reserved.

The holographic dual of a Riemann problem in a large number of dimensions

Energy Technology Data Exchange (ETDEWEB)

Herzog, Christopher P.; Spillane, Michael [C.N. Yang Institute for Theoretical Physics, Department of Physics and Astronomy,Stony Brook University, Stony Brook, NY 11794 (United States); Yarom, Amos [Department of Physics, Technion,Haifa 32000 (Israel)

2016-08-22

We study properties of a non equilibrium steady state generated when two heat baths are initially in contact with one another. The dynamics of the system we study are governed by holographic duality in a large number of dimensions. We discuss the “phase diagram” associated with the steady state, the dual, dynamical, black hole description of this problem, and its relation to the fluid/gravity correspondence.

Discussion: Comparison of slope instability screening tools following a large storm event and application to forest management and policy

Science.gov (United States)

Lingley, Leslie; Slaughter, Stephen L.; Sarikhan, Isabelle Y.; Norman, David K.

2013-02-01

This discussion is in response to the article entitled "Comparison of slope stability screening tools following a large storm event and application to forest management and policy" by Kara Whittaker and Dan McShane (Geomorphology 145-146 (2012) 115-122). The discussion is coauthored by several geologists at the Washington Department of Natural Resources (WDNR) including those from the research and policy sections of the state agency.

Screening for copy-number alterations and loss of heterozygosity in chronic lymphocytic leukemia--a comparative study of four differently designed, high resolution microarray platforms

DEFF Research Database (Denmark)

Gunnarsson, R.; Staaf, J.; Jansson, M.

2008-01-01

Screening for gene copy-number alterations (CNAs) has improved by applying genome-wide microarrays, where SNP arrays also allow analysis of loss of heterozygozity (LOH). We here analyzed 10 chronic lymphocytic leukemia (CLL) samples using four different high-resolution platforms: BAC arrays (32K)...

ON AN EXPONENTIAL INEQUALITY AND A STRONG LAW OF LARGE NUMBERS FOR MONOTONE MEASURES

Czech Academy of Sciences Publication Activity Database

Agahi, H.; Mesiar, Radko

2014-01-01

Roč. 50, č. 5 (2014), s. 804-813 ISSN 0023-5954 Institutional support: RVO:67985556 Keywords : Choquet expectation * a strong law of large numbers * exponential inequality * monotone probability Subject RIV: BA - General Mathematics Impact factor: 0.541, year: 2014 http://library.utia.cas.cz/separaty/2014/E/mesiar-0438052.pdf

Screening for abdominalt aortaaneurisme

DEFF Research Database (Denmark)

Lindholt, J S; Juul, Svend; Henneberg, E W

1997-01-01

rupture. Ultrasonographic screening for AAA takes 10 minutes per scan, and the sensitivity and specificity are high. Ultrasonographic screening for AAA is a reliable, safe and inexpensive method for screening, and screening for AAA is discussed worldwide. One point four percent of deaths among men from 65...... to 80 year of age are caused by ruptured AAA. Screening men over 65 for AAA can theoretically prevent a substantial number of deaths. Our calculations predict one prevented AAA-death per 200-300 scans for a cost of about 4000 DKK per saved year of life. However, cost-benefit analyses are based...... on uncertain assumptions concerning prevalence, incidence and risk of rupture. Therefore a randomized trial screening of 65-73 year old males is taking place in the County of Viborg in Denmark. Udgivelsesdato: 1997-Mar-24...

Modelling high Reynolds number wall-turbulence interactions in laboratory experiments using large-scale free-stream turbulence.

Science.gov (United States)

Dogan, Eda; Hearst, R Jason; Ganapathisubramani, Bharathram

2017-03-13

A turbulent boundary layer subjected to free-stream turbulence is investigated in order to ascertain the scale interactions that dominate the near-wall region. The results are discussed in relation to a canonical high Reynolds number turbulent boundary layer because previous studies have reported considerable similarities between these two flows. Measurements were acquired simultaneously from four hot wires mounted to a rake which was traversed through the boundary layer. Particular focus is given to two main features of both canonical high Reynolds number boundary layers and boundary layers subjected to free-stream turbulence: (i) the footprint of the large scales in the logarithmic region on the near-wall small scales, specifically the modulating interaction between these scales, and (ii) the phase difference in amplitude modulation. The potential for a turbulent boundary layer subjected to free-stream turbulence to 'simulate' high Reynolds number wall-turbulence interactions is discussed. The results of this study have encouraging implications for future investigations of the fundamental scale interactions that take place in high Reynolds number flows as it demonstrates that these can be achieved at typical laboratory scales.This article is part of the themed issue 'Toward the development of high-fidelity models of wall turbulence at large Reynolds number'. © 2017 The Author(s).

Copy number variation of KIR genes influences HIV-1 control

DEFF Research Database (Denmark)

Pelak, Kimberly; Need, Anna C; Fellay, Jacques

2011-01-01

A genome-wide screen for large structural variants showed that a copy number variant (CNV) in the region encoding killer cell immunoglobulin-like receptors (KIR) associates with HIV-1 control as measured by plasma viral load at set point in individuals of European ancestry. This CNV encompasses...... the KIR3DL1-KIR3DS1 locus, encoding receptors that interact with specific HLA-Bw4 molecules to regulate the activation of lymphocyte subsets including natural killer (NK) cells. We quantified the number of copies of KIR3DS1 and KIR3DL1 in a large HIV-1 positive cohort, and showed that an increase in KIR3...... amounts of these activating and inhibitory KIR play a role in regulating the peripheral expansion of highly antiviral KIR3DS1+ NK cells, which may determine differences in HIV-1 control following infection....

Large Eddy Simulation of an SD7003 Airfoil: Effects of Reynolds number and Subgrid-scale modeling

DEFF Research Database (Denmark)

Sarlak Chivaee, Hamid

2017-01-01

This paper presents results of a series of numerical simulations in order to study aerodynamic characteristics of the low Reynolds number Selig-Donovan airfoil, SD7003. Large Eddy Simulation (LES) technique is used for all computations at chord-based Reynolds numbers 10,000, 24,000 and 60...... the Reynolds number, and the effect is visible even at a relatively low chord-Reynolds number of 60,000. Among the tested models, the dynamic Smagorinsky gives the poorest predictions of the flow, with overprediction of lift and a larger separation on airfoils suction side. Among various models, the implicit...

ScreenBEAM: a novel meta-analysis algorithm for functional genomics screens via Bayesian hierarchical modeling.

Science.gov (United States)

Yu, Jiyang; Silva, Jose; Califano, Andrea

2016-01-15

Functional genomics (FG) screens, using RNAi or CRISPR technology, have become a standard tool for systematic, genome-wide loss-of-function studies for therapeutic target discovery. As in many large-scale assays, however, off-target effects, variable reagents' potency and experimental noise must be accounted for appropriately control for false positives. Indeed, rigorous statistical analysis of high-throughput FG screening data remains challenging, particularly when integrative analyses are used to combine multiple sh/sgRNAs targeting the same gene in the library. We use large RNAi and CRISPR repositories that are publicly available to evaluate a novel meta-analysis approach for FG screens via Bayesian hierarchical modeling, Screening Bayesian Evaluation and Analysis Method (ScreenBEAM). Results from our analysis show that the proposed strategy, which seamlessly combines all available data, robustly outperforms classical algorithms developed for microarray data sets as well as recent approaches designed for next generation sequencing technologies. Remarkably, the ScreenBEAM algorithm works well even when the quality of FG screens is relatively low, which accounts for about 80-95% of the public datasets. R package and source code are available at: https://github.com/jyyu/ScreenBEAM. ac2248@columbia.edu, jose.silva@mssm.edu, yujiyang@gmail.com Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Computational correction of copy number effect improves specificity of CRISPR-Cas9 essentiality screens in cancer cells. | Office of Cancer Genomics

Science.gov (United States)

The CRISPR-Cas9 system has revolutionized gene editing both at single genes and in multiplexed loss-of-function screens, thus enabling precise genome-scale identification of genes essential for proliferation and survival of cancer cells. However, previous studies have reported that a gene-independent antiproliferative effect of Cas9-mediated DNA cleavage confounds such measurement of genetic dependency, thereby leading to false-positive results in copy number-amplified regions.

Carrier Screening

Science.gov (United States)

... How accurate is carrier screening? No test is perfect. In a small number of cases, test results ... in which an egg is removed from a woman’s ovary, fertilized in a laboratory with the man’s ...

Correlates of women’s intentions to be screened for human papillomavirus for cervical cancer screening with an extended interval

Directory of Open Access Journals (Sweden)

Gina S. Ogilvie

2016-03-01

Full Text Available Abstract Background High-risk HPV DNA testing has been proposed as a primary tool for cervical cancer screening (HPV-CCS as an alternative to the Papanicolaou cytology- method. This study describes factors associated with women’s intentions to attend cervical cancer screening if high-risk HPV DNA testing (HPV-CCS was implemented as a primary screening tool, and if screening were conducted every 4 years starting after age 25. Methods This online survey was designed using the Theory of Planned Behaviour to assess factors that impact women’s intentions to attend HPV-CCS among women aged 25–69 upon exit of the HPV FOCAL trial. Univariate and regression analyses were performed to compare the demographic, sexual history, and smoking characteristics between women willing and unwilling to screen, and scales for intention to attend HPV-CCS. A qualitative analysis was performed by compiling and coding the comments section of the survey. Results Of the 981 women who completed the survey in full, only 51.4 % responded that they intended to attend HPV-CCS with a delayed start age and extended screening interval. Women who intended to screen were more likely to have higher education (AOR 0.59, 95 % CI [0.37, 0.93], while both positive attitudes (AOR 1.26, 95 % CI [1.23, 1.30] and perceived behavior control (AOR 1.06, 95 % CI [1.02, 1.10] were significant predictors of intention to screen. Among women who provided comments in the survey, a large number of women expressed fears about not being checked more than every 4 years, but 12 % stated that these fears may be alleviated by having more information. Conclusions Acceptability of increased screening intervals and starting age could be improved through enhanced education of benefits. Program planners should consider measures to assess and improve women’s knowledge, attitudes and beliefs prior to the implementation of new screening programs to avoid unintended consequences.

Particle creation and Dirac's large number hypothesis; and Reply

International Nuclear Information System (INIS)

Canuto, V.; Adams, P.J.; Hsieh, S.H.; Tsiang, E.; Steigman, G.

1976-01-01

The claim made by Steigman (Nature; 261:479 (1976)), that the creation of matter as postulated by Dirac (Proc. R. Soc.; A338:439 (1974)) is unnecessary, is here shown to be incorrect. It is stated that Steigman's claim that Dirac's large Number Hypothesis (LNH) does not require particle creation is wrong because he has assumed that which he was seeking to prove, that is that rho does not contain matter creation. Steigman's claim that Dirac's LNH leads to nonsensical results in the very early Universe is superficially correct, but this only supports Dirac's contention that the LNH may not be valid in the very early Universe. In a reply Steigman points out that in Dirac's original cosmology R approximately tsup(1/3) and using this model the results and conclusions of the present author's paper do apply but using a variation chosen by Canuto et al (T approximately t) Dirac's LNH cannot apply. Additionally it is observed that a cosmological theory which only predicts the present epoch is of questionable value. (U.K.)

Decision aid on breast cancer screening reduces attendance rate: results of a large-scale, randomized, controlled study by the DECIDEO group

Science.gov (United States)

Bourmaud, Aurelie; Soler-Michel, Patricia; Oriol, Mathieu; Regnier, Véronique; Tinquaut, Fabien; Nourissat, Alice; Bremond, Alain; Moumjid, Nora; Chauvin, Franck

2016-01-01

Controversies regarding the benefits of breast cancer screening programs have led to the promotion of new strategies taking into account individual preferences, such as decision aid. The aim of this study was to assess the impact of a decision aid leaflet on the participation of women invited to participate in a national breast cancer screening program. This Randomized, multicentre, controlled trial. Women aged 50 to 74 years, were randomly assigned to receive either a decision aid or the usual invitation letter. Primary outcome was the participation rate 12 months after the invitation. 16 000 women were randomized and 15 844 included in the modified intention-to-treat analysis. The participation rate in the intervention group was 40.25% (3174/7885 women) compared with 42.13% (3353/7959) in the control group (p = 0.02). Previous attendance for screening (RR = 6.24; [95%IC: 5.75-6.77]; p < 0.0001) and medium household income (RR = 1.05; [95%IC: 1.01-1.09]; p = 0.0074) were independently associated with attendance for screening. This large-scale study demonstrates that the decision aid reduced the participation rate. The decision aid activate the decision making process of women toward non-attendance to screening. These results show the importance of promoting informed patient choices, especially when those choices cannot be anticipated. PMID:26883201

Strong Laws of Large Numbers for Arrays of Rowwise NA and LNQD Random Variables

Directory of Open Access Journals (Sweden)

Jiangfeng Wang

2011-01-01

Full Text Available Some strong laws of large numbers and strong convergence properties for arrays of rowwise negatively associated and linearly negative quadrant dependent random variables are obtained. The results obtained not only generalize the result of Hu and Taylor to negatively associated and linearly negative quadrant dependent random variables, but also improve it.

Law of large numbers and central limit theorem for randomly forced PDE's

CERN Document Server

Shirikyan, A

2004-01-01

We consider a class of dissipative PDE's perturbed by an external random force. Under the condition that the distribution of perturbation is sufficiently non-degenerate, a strong law of large numbers (SLLN) and a central limit theorem (CLT) for solutions are established and the corresponding rates of convergence are estimated. It is also shown that the estimates obtained are close to being optimal. The proofs are based on the property of exponential mixing for the problem in question and some abstract SLLN and CLT for mixing-type Markov processes.

A selective overview of feature screening for ultrahigh-dimensional data.

Science.gov (United States)

JingYuan, Liu; Wei, Zhong; RunZe, L I

2015-10-01

High-dimensional data have frequently been collected in many scientific areas including genomewide association study, biomedical imaging, tomography, tumor classifications, and finance. Analysis of high-dimensional data poses many challenges for statisticians. Feature selection and variable selection are fundamental for high-dimensional data analysis. The sparsity principle, which assumes that only a small number of predictors contribute to the response, is frequently adopted and deemed useful in the analysis of high-dimensional data. Following this general principle, a large number of variable selection approaches via penalized least squares or likelihood have been developed in the recent literature to estimate a sparse model and select significant variables simultaneously. While the penalized variable selection methods have been successfully applied in many high-dimensional analyses, modern applications in areas such as genomics and proteomics push the dimensionality of data to an even larger scale, where the dimension of data may grow exponentially with the sample size. This has been called ultrahigh-dimensional data in the literature. This work aims to present a selective overview of feature screening procedures for ultrahigh-dimensional data. We focus on insights into how to construct marginal utilities for feature screening on specific models and motivation for the need of model-free feature screening procedures.

Screen Space Ambient Occlusion Based Multiple Importance Sampling for Real-Time Rendering

Science.gov (United States)

Zerari, Abd El Mouméne; Babahenini, Mohamed Chaouki

2018-03-01

We propose a new approximation technique for accelerating the Global Illumination algorithm for real-time rendering. The proposed approach is based on the Screen-Space Ambient Occlusion (SSAO) method, which approximates the global illumination for large, fully dynamic scenes at interactive frame rates. Current algorithms that are based on the SSAO method suffer from difficulties due to the large number of samples that are required. In this paper, we propose an improvement to the SSAO technique by integrating it with a Multiple Importance Sampling technique that combines a stratified sampling method with an importance sampling method, with the objective of reducing the number of samples. Experimental evaluation demonstrates that our technique can produce high-quality images in real time and is significantly faster than traditional techniques.

Substance use outcomes of patients served by a large US implementation of Screening, Brief Intervention and Referral to Treatment (SBIRT).

Science.gov (United States)

Aldridge, Arnie; Linford, Robyn; Bray, Jeremy

2017-02-01

To estimate changes in the substance use behaviors of patients who received services as part of the US Substance Abuse and Mental Health Services Administration's (SAMHSA) Screening, Brief Intervention and Referral to Treatment (SBIRT) grant program. We use a pre-post design and performance monitoring data collected by SBIRT organizations. For a sample of 17 575 patients, we compare pre-SBIRT substance use with substance use 6 months after receipt of SBIRT services. SBIRT's correlation with changes in substance use was estimated using generalized linear mixed models to account for the clustering of patients within health-care facility and US state. From pre- to post-SBIRT we found large and statistically significant decreases for almost every measure of substance use. Model-adjusted means indicate that the prevalence of alcohol use was lower 6 months later by 35.6%, heavy drinking by 43.4% and illicit drug use by 75.8%. Greater intervention intensity was associated with larger decreases in substance use. The study design does not support causal conclusions and estimated decreases in reported substance use are due, at least in part, to a well-known set of confounders and natural substance use patterns that may be unrelated to any particular SBIRT intervention. Compared with previously published findings on the Screening, Brief Intervention and Referral to Treatment grant program, our estimates of substance use reduction were smaller, but still consistently large in absolute magnitude and within ranges of estimates from past trials of Screening, Brief Intervention and Referral to Treatment. © 2017 Society for the Study of Addiction.

Large scale meta-analysis of fragment-based screening campaigns: privileged fragments and complementary technologies.

Science.gov (United States)

Kutchukian, Peter S; Wassermann, Anne Mai; Lindvall, Mika K; Wright, S Kirk; Ottl, Johannes; Jacob, Jaison; Scheufler, Clemens; Marzinzik, Andreas; Brooijmans, Natasja; Glick, Meir

2015-06-01

A first step in fragment-based drug discovery (FBDD) often entails a fragment-based screen (FBS) to identify fragment "hits." However, the integration of conflicting results from orthogonal screens remains a challenge. Here we present a meta-analysis of 35 fragment-based campaigns at Novartis, which employed a generic 1400-fragment library against diverse target families using various biophysical and biochemical techniques. By statistically interrogating the multidimensional FBS data, we sought to investigate three questions: (1) What makes a fragment amenable for FBS? (2) How do hits from different fragment screening technologies and target classes compare with each other? (3) What is the best way to pair FBS assay technologies? In doing so, we identified substructures that were privileged for specific target classes, as well as fragments that were privileged for authentic activity against many targets. We also revealed some of the discrepancies between technologies. Finally, we uncovered a simple rule of thumb in screening strategy: when choosing two technologies for a campaign, pairing a biochemical and biophysical screen tends to yield the greatest coverage of authentic hits. © 2014 Society for Laboratory Automation and Screening.

Correction of Microplate Data from High-Throughput Screening.

Science.gov (United States)

Wang, Yuhong; Huang, Ruili

2016-01-01

High-throughput screening (HTS) makes it possible to collect cellular response data from a large number of cell lines and small molecules in a timely and cost-effective manner. The errors and noises in the microplate-formatted data from HTS have unique characteristics, and they can be generally grouped into three categories: run-wise (temporal, multiple plates), plate-wise (background pattern, single plate), and well-wise (single well). In this chapter, we describe a systematic solution for identifying and correcting such errors and noises, mainly basing on pattern recognition and digital signal processing technologies.

Population-based screening versus case detection.

Directory of Open Access Journals (Sweden)

Thomas Ravi

2002-01-01

Full Text Available India has a large burden of blindness and population-based screening is a strategy commonly employed to detect disease and prevent morbidity. However, not all diseases are amenable to screening. This communication examines the issue of "population-based screening" versus "case detection" in the Indian scenario. Using the example of glaucoma, it demonstrates that given the poor infrastructure, for a "rare" disease, case detection is more effective than population-based screening.

Large Scale Screening of Low Cost Ferritic Steel Designs For Advanced Ultra Supercritical Boiler Using First Principles Methods

Energy Technology Data Exchange (ETDEWEB)

Ouyang, Lizhi [Tennessee State Univ. Nashville, TN (United States)

2016-11-29

Advanced Ultra Supercritical Boiler (AUSC) requires materials that can operate in corrosive environment at temperature and pressure as high as 760°C (or 1400°F) and 5000psi, respectively, while at the same time maintain good ductility at low temperature. We develop automated simulation software tools to enable fast large scale screening studies of candidate designs. While direct evaluation of creep rupture strength and ductility are currently not feasible, properties such as energy, elastic constants, surface energy, interface energy, and stack fault energy can be used to assess their relative ductility and creeping strength. We implemented software to automate the complex calculations to minimize human inputs in the tedious screening studies which involve model structures generation, settings for first principles calculations, results analysis and reporting. The software developed in the project and library of computed mechanical properties of phases found in ferritic steels, many are complex solid solutions estimated for the first time, will certainly help the development of low cost ferritic steel for AUSC.

Vibration characteristics of an inclined flip-flow screen panel in banana flip-flow screens

Science.gov (United States)

Xiong, Xiaoyan; Niu, Linkai; Gu, Chengxiang; Wang, Yinhua

2017-12-01

A banana flip-flow screen is an effective solution for the screening of high-viscosity, high-water and fine materials. As one of the key components, the vibration characteristics of the inclined flip-flow screen panel largely affects the screen performance and the processing capacity. In this paper, a mathematical model for the vibration characteristic of the inclined flip-flow screen panel is proposed based on Catenary theory. The reasonability of Catenary theory in analyzing the vibration characteristic of flip-flow screen panels is verified by a published experiment. Moreover, the effects of the rotation speed of exciters, the incline angle, the slack length and the characteristics of the screen on the vertical deflection, the vertical velocity and the vertical acceleration of the screen panel are investigated parametrically. The results show that the rotation speed of exciters, the incline angle, the slack length and the characteristics of the screen have significant effects on the vibrations of an inclined flip-flow screen panel, and these parameters should be optimized.

Breast cancer screening in older women.

Science.gov (United States)

Caplan, L S; Haynes, S G

1996-01-01

There is currently an epidemic of breast cancer in women 65 years of age and older. The purposes of this paper are to explore the breast cancer screening behaviors of older women and to identify some of the determinants of screening in these women. Data were analyzed from the 1987 National Health Interview Survey, a continuous nationwide household interview survey of the U.S. civilian, noninstitutionalized population. As in other studies, the utilization of breast cancer screening by older women was less in older women than in younger women. This was true for both mammography and clinical breast examination. A number of determinants of screening in older women were identified here. Women with a usual source of care and/or no activity limitation, as well as high school graduates, were the ones most likely to have received a screening mammogram and/or a screening clinical breast exam during the past year. The failure of older women to receive adequate breast cancer screening is an important concern which should be reevaluated, given the breast cancer epidemic in this population. This study identified a number of determinants of breast cancer screening in older women. For the most part, these determinants point to the primary care physician as the key to breast cancer screening in these women. Therefore, the primary care physician must be informed of, and encouraged to follow, the recommendations for periodic breast cancer screening in older women.

Development of a large-screen high-definition laser video projection system

Science.gov (United States)

Clynick, Tony J.

1991-08-01

A prototype laser video projector which uses electronic, optical, and mechanical means to project a television picture is described. With the primary goal of commercial viability, the price/performance ratio of the chosen means is critical. The fundamental requirement has been to achieve high brightness, high definition images of at least movie-theater size, at a cost comparable with other existing large-screen video projection technologies, while having the opportunity of developing and exploiting the unique properties of the laser projected image, such as its infinite depth-of-field. Two argon lasers are used in combination with a dye laser to achieve a range of colors which, despite not being identical to those of a CRT, prove to be subjectively acceptable. Acousto-optic modulation in combination with a rotary polygon scanner, digital video line stores, novel specialized electro-optics, and a galvanometric frame scanner form the basis of the projection technique achieving a 30 MHz video bandwidth, high- definition scan rates (1125/60 and 1250/50), high contrast ratio, and good optical efficiency. Auditorium projection of HDTV pictures wider than 20 meters are possible. Applications including 360 degree(s) projection and 3-D video provide further scope for exploitation of the HD laser video projector.

On the Behavior of ECN/RED Gateways Under a Large Number of TCP Flows: Limit Theorems

National Research Council Canada - National Science Library

Tinnakornsrisuphap, Peerapol; Makowski, Armand M

2005-01-01

.... As the number of competing flows becomes large, the asymptotic queue behavior at the gateway can be described by a simple recursion and the throughput behavior of individual TCP flows becomes asymptotically independent...

Impact of Cell-Free Fetal DNA Screening on Patients’ Choice of Invasive Procedures after a Positive California Prenatal Screen Result

Directory of Open Access Journals (Sweden)

Forum T. Shah

2014-07-01

Full Text Available Until recently, maternal serum analyte levels paired with sonographic fetal nuchal translucency measurement was the most accurate prenatal screen available for Trisomies 18 and 21, (91% and 94% detection and false positive rates of 0.31% and 4.5% respectively. Women with positive California Prenatal Screening Program (CPSP results have the option of diagnostic testing to determine definitively if the fetus has a chromosomal abnormality. Cell-free fetal (cff- DNA screening for Trisomies 13, 18, and 21 was first offered in 2012, allowing women with positive screens to choose additional screening before diagnostic testing. Cff-DNA sensitivity rates are as high as 99.9% and 99.1%, with false positive rates of 0.4% and 0.1%, for Trisomies 18 and 21, respectively. A retrospective chart review was performed in 2012 on 500 CPSP referrals at the University of California, San Diego Thornton Hospital. Data were collected prior to and after the introduction of cff-DNA. There was a significant increase in the number of participants who chose to pursue additional testing and a decrease in the number of invasive procedures performed after cff-DNA screening was available. We conclude that as fetal aneuploidy screening improves, the number of invasive procedures will continue to decrease.

Is mammography screening history a predictor of future breast cancer risk?

DEFF Research Database (Denmark)

Andersen, Sune Bangsbøll; Törnberg, Sven; Kilpeläinen, Sini

2015-01-01

Inspired by the model by Walter and Day for risk of cervical cancer following negative screens, one might hypothesize that women in a mammography screening programme with a certain number of negative screens had a lower remaining breast cancer risk than that of women in general. We studied whether...... number of negative screens was a predictor for a low remaining breast cancer risk in women participating in the mammography screening programmes in Stockholm, Copenhagen and Funen. Data were collected from the mammography screening programmes in Stockholm, Sweden (1989-2012), Copenhagen, Denmark (1991......-2009) and Funen, Denmark (1993-2009), and linked to the respective cancer registries. We calculated cumulative hazard rates for breast cancer in women in cohorts defined by age at entry and number of negative screens for the maximum follow-up period in each screening centre. For all centres and cohorts...

Malnutrition risk in hospitalized children : use of 3 screening tools in a large European population

NARCIS (Netherlands)

Chourdakis, Michael; Hecht, Christina; Gerasimidis, Konstantinos; Joosten, Koen F. M.; Karagiozoglou-Lainpoudi, Thomais; Koetse, Harma A.; Ksiazyk, Janusz; Lazea, Cecilia; Shamir, Raanan; Szajewska, Hania; Koletzko, Berthold; Hulst, Jessie M.

Background: Several malnutrition screening tools have been advocated for use in pediatric inpatients. Objective: We evaluated how 3 popular pediatric nutrition screening tools [i.e., the Pediatric Yorkhill Malnutrition Score (PYMS), the Screening Tool for the Assessment of Malnutrition in Pediatrics

Reading with Mobile Phone & Large Display

OpenAIRE

Gostner, Roswitha; Gellersen, Hans; Kray, Christian; Sas, Corina

2008-01-01

In this paper we compare performance and usability between three different device combinations: a) mobile phone b) touch screen c) mobile phone & screen. We show that mobile phone & screen has a better perform-ance than phone only. We also discuss some interaction issues when using a mobile phone with a large screen.

Prostate Cancer Screening Results from PLCO

Science.gov (United States)

Learn the results of the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, a large-scale clinical trial to determine whether certain cancer screening tests can help reduce deaths from prostate, lung, colorectal, and ovarian cancer.

Five year colorectal cancer outcomes in a large negative CT colonography screening cohort

Energy Technology Data Exchange (ETDEWEB)

Kim, David H.; Pooler, B.D.; Pickhardt, Perry J. [University of Wisconsin School of Medicine and Public Health, Department of Radiology, Madison, WI (United States); Weiss, Jennifer M. [University of Wisconsin School of Medicine and Public Health, Section of Gastroenterology, Department of Internal Medicine, Madison, WI (United States)

2012-07-15

To assess the 5-year incidence of clinically presenting colorectal cancers following a negative CT colonography (CTC) screening examination, as few patient outcome data regarding a negative CTC screening result exist. Negative CTC screening patients (n = 1,050) in the University of Wisconsin Health system over a 14-month period were included. An electronic medical record (EMR) review was undertaken, encompassing provider, colonoscopy, imaging and histopathology reports. Incident colorectal cancers and other important GI tumours were recorded. Of the 1,050 cohort (mean [{+-}SD] age 56.9 {+-} 7.4 years), 39 (3.7%) patients were excluded owing to lack of follow-up within our system beyond the initial screening CTC. The remaining 1,011 patients were followed for an average of 4.73 {+-} 1.15 years. One incident colorectal adenocarcinoma represented a crude cancer incidence of 0.2 cancers per 1,000 patient years. EMR revealed 14 additional patients with clinically important GI tumours including: advanced adenomas (n = 11), appendiceal goblet cell carcinoid (n = 1), appendiceal mucinous adenoma (n = 1) and metastatic ileocolonic carcinoid (n = 1). All positive patients including the incident carcinoma are alive at the time of review. Clinically presenting colorectal adenocarcinoma is rare in the 5 years following negative screening CTC, suggesting that current strategies, including non-reporting of diminutive lesions, are appropriate. (orig.)

Five year colorectal cancer outcomes in a large negative CT colonography screening cohort

International Nuclear Information System (INIS)

Kim, David H.; Pooler, B.D.; Pickhardt, Perry J.; Weiss, Jennifer M.

2012-01-01

To assess the 5-year incidence of clinically presenting colorectal cancers following a negative CT colonography (CTC) screening examination, as few patient outcome data regarding a negative CTC screening result exist. Negative CTC screening patients (n = 1,050) in the University of Wisconsin Health system over a 14-month period were included. An electronic medical record (EMR) review was undertaken, encompassing provider, colonoscopy, imaging and histopathology reports. Incident colorectal cancers and other important GI tumours were recorded. Of the 1,050 cohort (mean [±SD] age 56.9 ± 7.4 years), 39 (3.7%) patients were excluded owing to lack of follow-up within our system beyond the initial screening CTC. The remaining 1,011 patients were followed for an average of 4.73 ± 1.15 years. One incident colorectal adenocarcinoma represented a crude cancer incidence of 0.2 cancers per 1,000 patient years. EMR revealed 14 additional patients with clinically important GI tumours including: advanced adenomas (n = 11), appendiceal goblet cell carcinoid (n = 1), appendiceal mucinous adenoma (n = 1) and metastatic ileocolonic carcinoid (n = 1). All positive patients including the incident carcinoma are alive at the time of review. Clinically presenting colorectal adenocarcinoma is rare in the 5 years following negative screening CTC, suggesting that current strategies, including non-reporting of diminutive lesions, are appropriate. (orig.)

[Surgery for colorectal cancer since the introduction of the Netherlands national screening programmeInvestigations into changes in number of resections and waiting times for surgery].

Science.gov (United States)

de Neree Tot Babberich, M P M; van der Willik, E M; van Groningen, J T; Ledeboer, M; Wiggers, T; Wouters, M W J M

2017-01-01

To investigate the impact of the Netherlands national colorectal cancer screening programme on the number of surgical resections for colorectal carcinoma and on waiting times for surgery. Descriptive study. Data were extracted from the Dutch Surgical Colorectal Audit. Patients with primary colorectal cancer surgery between 2011-2015 were included. The volume and median waiting times for the years 2011-2015 are described. Waiting times from first tumor positive biopsy until the operation (biopsy-operation) and first preoperative visit to the surgeon until the operation (visit-operation) are analyzed with a univariate and multivariate linear regression analysis. Separate analysis was done for visit-operation for academic and non-academic hospitals and for screening compared to non-screening patients. In 2014 there was an increase of 1469 (15%) patients compared to 2013. In 2015 this increase consisted of 1168 (11%) patients compared to 2014. In 2014 and 2015, 1359 (12%) and 3111 (26%) patients were referred to the surgeon through screening, respectively. The median waiting time of biopsy-operation significantly decreased (ß: 0.94, 95%BI) over the years 2014-2015 compared to 2011-2013. In non-academic hospitals, the waiting time visit-operation also decreased significantly (ß: 0.89, 95%BI 0.87-0.90) over the years 2014-2015 compared to 2011-2013. No difference was found in waiting times between patients referred to the surgeon through screening compared to non-screening. There is a clear increase in volume since the introduction of the colorectal cancer screening programme without an increase in waiting time until surgery.

The cumulative risk of false-positive screening results across screening centres in the Norwegian Breast Cancer Screening Program

Energy Technology Data Exchange (ETDEWEB)

Roman, M., E-mail: Marta.Roman@kreftregisteret.no [Cancer Registry of Norway, Oslo (Norway); Department of Women and Children’s Health, Oslo University Hospital, Oslo (Norway); Skaane, P., E-mail: PERSK@ous-hf.no [Department of Radiology, Oslo University Hospital Ullevaal, University of Oslo, Oslo (Norway); Hofvind, S., E-mail: Solveig.Hofvind@kreftregisteret.no [Cancer Registry of Norway, Oslo (Norway); Oslo and Akershus University College of Applied Sciences, Faculty of Health Science, Oslo (Norway)

2014-09-15

Highlights: • We found variation in early performance measures across screening centres. • Radiologists’ performance may play a key role in the variability. • Potential to improve the effectiveness of breast cancer screening programs. • Continuous surveillance of screening centres and radiologists is essential. - Abstract: Background: Recall for assessment in mammographic screening entails an inevitable number of false-positive screening results. This study aimed to investigate the variation in the cumulative risk of a false positive screening result and the positive predictive value across the screening centres in the Norwegian Breast Cancer Screening Program. Methods: We studied 618,636 women aged 50–69 years who underwent 2,090,575 screening exams (1996–2010. Recall rate, positive predictive value, rate of screen-detected cancer, and the cumulative risk of a false positive screening result, without and with invasive procedures across the screening centres were calculated. Generalized linear models were used to estimate the probability of a false positive screening result and to compute the cumulative false-positive risk for up to ten biennial screening examinations. Results: The cumulative risk of a false-positive screening exam varied from 10.7% (95% CI: 9.4–12.0%) to 41.5% (95% CI: 34.1–48.9%) across screening centres, with a highest to lowest ratio of 3.9 (95% CI: 3.7–4.0). The highest to lowest ratio for the cumulative risk of undergoing an invasive procedure with a benign outcome was 4.3 (95% CI: 4.0–4.6). The positive predictive value of recall varied between 12.0% (95% CI: 11.0–12.9%) and 19.9% (95% CI: 18.3–21.5%), with a highest to lowest ratio of 1.7 (95% CI: 1.5–1.9). Conclusions: A substantial variation in the performance measures across the screening centres in the Norwegian Breast Cancer Screening Program was identified, despite of similar administration, procedures, and quality assurance requirements. Differences in the

The cumulative risk of false-positive screening results across screening centres in the Norwegian Breast Cancer Screening Program

International Nuclear Information System (INIS)

Roman, M.; Skaane, P.; Hofvind, S.

2014-01-01

Highlights: • We found variation in early performance measures across screening centres. • Radiologists’ performance may play a key role in the variability. • Potential to improve the effectiveness of breast cancer screening programs. • Continuous surveillance of screening centres and radiologists is essential. - Abstract: Background: Recall for assessment in mammographic screening entails an inevitable number of false-positive screening results. This study aimed to investigate the variation in the cumulative risk of a false positive screening result and the positive predictive value across the screening centres in the Norwegian Breast Cancer Screening Program. Methods: We studied 618,636 women aged 50–69 years who underwent 2,090,575 screening exams (1996–2010. Recall rate, positive predictive value, rate of screen-detected cancer, and the cumulative risk of a false positive screening result, without and with invasive procedures across the screening centres were calculated. Generalized linear models were used to estimate the probability of a false positive screening result and to compute the cumulative false-positive risk for up to ten biennial screening examinations. Results: The cumulative risk of a false-positive screening exam varied from 10.7% (95% CI: 9.4–12.0%) to 41.5% (95% CI: 34.1–48.9%) across screening centres, with a highest to lowest ratio of 3.9 (95% CI: 3.7–4.0). The highest to lowest ratio for the cumulative risk of undergoing an invasive procedure with a benign outcome was 4.3 (95% CI: 4.0–4.6). The positive predictive value of recall varied between 12.0% (95% CI: 11.0–12.9%) and 19.9% (95% CI: 18.3–21.5%), with a highest to lowest ratio of 1.7 (95% CI: 1.5–1.9). Conclusions: A substantial variation in the performance measures across the screening centres in the Norwegian Breast Cancer Screening Program was identified, despite of similar administration, procedures, and quality assurance requirements. Differences in the

Laboratory screening markers in gastroenterology--state of the art.

Science.gov (United States)

Kocna, Petr; Vanickova, Zdislava; Zima, Tomas

2013-06-01

Screening tests for gastrointestinal diseases acceptable for population with a high sensitivity and high specificity can now be offered by clinical laboratories. This paper summarizes major recent advances in this area of laboratory medicine. Relevant articles published within the last 5 years in the NLM (National Library of Medicine) PubMed - Medline database covering the three gastrointestinal diseases - colorectal cancer, coeliac disease, and atrophic gastritis were included for this overview. In Europe, colorectal cancer (CRCA) is the second most frequent malignant disease. Quantitative immunochemical analysis of the stool for haemoglobin provides the best screening test to date, with both sensitivity and specificity approaching 95%. Even though coeliac disease (CD) affects approximately 1% of the general population, it remains largely unrecognised. Recommended methods for screening currently involve the detection of IgA and IgG antibodies against tissue transglutaminase and deamidated gliadin peptide. Evaluations of screening are now discussed for other diseases of the gastrointestinal tract - such as chronic atrophic gastritis (CAG), and inflammatory bowel disease (IBD). Detection of infection by Helicobacter pylori and stomach-specific plasmatic biomarkers, especially pepsinogen I/II ratio, could help with the prevention of gastric carcinomas. The use of faecal calprotectin as a screening test could substantially reduce the number of invasive methods necessary for the diagnostic work-up of patients with IBD. Screening tests for CRCA and CD have been used worldwide for many years. Screening strategies for gastrointestinal diseases are suggested in the text, based on recent basic science, clinical papers as well as our own experience.

Enzymatically Generated CRISPR Libraries for Genome Labeling and Screening.

Science.gov (United States)

Lane, Andrew B; Strzelecka, Magdalena; Ettinger, Andreas; Grenfell, Andrew W; Wittmann, Torsten; Heald, Rebecca

2015-08-10

CRISPR-based technologies have emerged as powerful tools to alter genomes and mark chromosomal loci, but an inexpensive method for generating large numbers of RNA guides for whole genome screening and labeling is lacking. Using a method that permits library construction from any source of DNA, we generated guide libraries that label repetitive loci or a single chromosomal locus in Xenopus egg extracts and show that a complex library can target the E. coli genome at high frequency. Copyright © 2015 Elsevier Inc. All rights reserved.

Non-destructive screening method for radiation hardened performance of large scale integration

International Nuclear Information System (INIS)

Zhou Dong; Xi Shanbin; Guo Qi; Ren Diyuan; Li Yudong; Sun Jing; Wen Lin

2013-01-01

The space radiation environment could induce radiation damage on the electronic devices. As the performance of commercial devices is generally superior to that of radiation hardened devices, it is necessary to screen out the devices with good radiation hardened performance from the commercial devices and applying these devices to space systems could improve the reliability of the systems. Combining the mathematical regression analysis with the different physical stressing experiments, we investigated the non-destructive screening method for radiation hardened performance of the integrated circuit. The relationship between the change of typical parameters and the radiation performance of the circuit was discussed. The irradiation-sensitive parameters were confirmed. The pluralistic linear regression equation toward the prediction of the radiation performance was established. Finally, the regression equations under stress conditions were verified by practical irradiation. The results show that the reliability and accuracy of the non-destructive screening method can be elevated by combining the mathematical regression analysis with the practical stressing experiment. (authors)

Determination of the SNPP VIIRS SDSM Screen Relative Transmittance From Both Yaw Maneuver and Regular On-Orbit Data

Science.gov (United States)

Lei, Ning; Chen, Xuexia; Xiong, Xiaoxiong

2015-01-01

The Visible Infrared Imaging Radiometer Suiteaboard the Suomi National Polar-orbiting Partnership (SNPP) satellite performs radiometric calibration of its reflective solar bands primarily through observing a sunlit onboard solar diffuser (SD). The SD bidirectional reflectance distribution function(BRDF) degradation factor is determined by an onboard SD stability monitor (SDSM), which observes the Sun through a pinhole screen and the sunlit SD. The transmittance of the SDSM pinhole screen over a range of solar angles was determined prelaunch and used initially to determine the BRDF degradation factor.The degradation-factor-versus-time curves were found to have a number of very large unphysical undulations likely due to the inaccuracy in the prelaunch determined SDSM screen transmittance.To refine the SDSM screen transmittance, satellite yaw maneuvers were carried out. With the SDSM screen relative transmittance determined from the yaw maneuver data, the computed BRDFdegradation factor curves still have large unphysical ripples, indicating that the projected solar horizontal angular step size in the yaw maneuver data is too large to resolve the transmittance at a fine angular scale. We develop a methodology to use both the yaw maneuver and a small portion of regular on-orbit data to determine the SDSM screen relative transmittance at a fine angular scale. We determine that the error standard deviation of the calculated relative transmittance ranges from 0.00030 (672 nm) to 0.00092 (926 nm). With the newly determined SDSM screen relative transmittance, the computed BRDF degradation factor behaves much more smoothly over time.

Tuberculosis screening in patients with HIV

DEFF Research Database (Denmark)

Bjerrum, Stephanie Mia Katrine; Bonsu, Frank; Hanson-Nortey, Nii Nortey

2016-01-01

BACKGROUND: Tuberculosis screening of people living with HIV (PLHIV) can contribute to early tuberculosis diagnosis and improved patient outcomes. Evidence-based guidelines for tuberculosis screening are available, but literature assessing their implementation and the quality of clinical practice...... is scarce. OBJECTIVES: To assess tuberculosis screening practices and the effectiveness of audit and performance feedback to improve quality of tuberculosis screening at HIV care clinics in Ghana. DESIGN: Healthcare providers at 10 large HIV care clinics prospectively registered patient consultations during...

SECRET SHARING SCHEMES WITH STRONG MULTIPLICATION AND A LARGE NUMBER OF PLAYERS FROM TORIC VARIETIES

DEFF Research Database (Denmark)

Hansen, Johan Peder

2017-01-01

This article consider Massey's construction for constructing linear secret sharing schemes from toric varieties over a finite field $\\Fq$ with $q$ elements. The number of players can be as large as $(q-1)^r-1$ for $r\\geq 1$. The schemes have strong multiplication, such schemes can be utilized in ...

Italian Euromelanoma Day Screening Campaign (2005-2007) and the planning of melanoma screening strategies.

Science.gov (United States)

Seidenari, Stefania; Benati, Elisa; Ponti, Giovanni; Borsari, Stefania; Ferrari, Chiara; Albertini, Giuseppe; Altomare, Gianfranco; Arcangeli, Fabio; Aste, Nicola; Bernengo, Maria Grazia; Bongiorno, Maria Rita; Borroni, Giovanni; Calvieri, Stefano; Chimenti, Sergio; Cusano, Francesco; Fracchiolla, Claudio; Gaddoni, Giuseppe; Girolomoni, Giampiero; Guarneri, Biagio; Lanzoni, Anna; Lombardi, Mara; Lotti, Torello; Mariotti, Antonio; Marsili, Franco; Micali, Giuseppe; Parodi, Aurora; Peris, Ketty; Peserico, Andrea; Quaglino, Pietro; Santini, Marcello; Schiavon, Sergio; Tonino, Camillo; Trevisan, Giusto; Tribuzi, Paola; Valentini, Paolo; Vena, Gino A; Virgili, Annarosa

2012-01-01

Although no study has definitively shown that unfocused screening of skin cancer is effective, many campaigns have been organized with the aim of increasing awareness on melanoma risk factors. The objective of this study was to analyse the results of the Skin Cancer Screening Day in Italy during the period 2005-2007, to determine the priorities for melanoma control plans in a Mediterranean country. A total of 5002 patients were screened by dermatologists in 31 cities. Individuals who considered themselves to have many naevi and those with a family history of melanoma showed a higher number of common and atypical naevi. Ten melanomas, 20 basal cell carcinomas and two squamous cell carcinomas were histopathologically confirmed. Our observations provide the following suggestions for melanoma prevention strategies: (a) an unfocused campaign is suitable to inform the public about the importance of self-examination of the skin, but is not useful to identify a larger number of melanomas; and (b) melanoma screening campaigns should focus on a selected population, which meets rigorous risk criteria to maintain higher cost-effectiveness. The financial support to effective melanoma screening programmes could be increased, especially in southern populations where lower levels of self-surveillance and socioeconomic conditions represent risk factors for late identification of melanoma.

Reverse screening methods to search for the protein targets of chemopreventive compounds

Science.gov (United States)

Huang, Hongbin; Zhang, Guigui; Zhou, Yuquan; Lin, Chenru; Chen, Suling; Lin, Yutong; Mai, Shangkang; Huang, Zunnan

2018-05-01

This article is a systematic review of reverse screening methods used to search for the protein targets of chemopreventive compounds or drugs. Typical chemopreventive compounds include components of traditional Chinese medicine, natural compounds and Food and Drug Administration (FDA)-approved drugs. Such compounds are somewhat selective but are predisposed to bind multiple protein targets distributed throughout diverse signaling pathways in human cells. In contrast to conventional virtual screening, which identifies the ligands of a targeted protein from a compound database, reverse screening is used to identify the potential targets or unintended targets of a given compound from a large number of receptors by examining their known ligands or crystal structures. This method, also known as in silico or computational target fishing, is highly valuable for discovering the target receptors of query molecules from terrestrial or marine natural products, exploring the molecular mechanisms of chemopreventive compounds, finding alternative indications of existing drugs by drug repositioning, and detecting adverse drug reactions and drug toxicity. Reverse screening can be divided into three major groups: shape screening, pharmacophore screening and reverse docking. Several large software packages, such as Schrödinger and Discovery Studio; typical software/network services such as ChemMapper, PharmMapper, idTarget and INVDOCK; and practical databases of known target ligands and receptor crystal structures, such as ChEMBL, BindingDB and the Protein Data Bank (PDB), are available for use in these computational methods. Different programs, online services and databases have different applications and constraints. Here, we conducted a systematic analysis and multilevel classification of the computational programs, online services and compound libraries available for shape screening, pharmacophore screening and reverse docking to enable non-specialist users to quickly learn and

Is the number of fast-food outlets in the neighbourhood related to screen-detected type 2 diabetes mellitus and associated risk factors?

Science.gov (United States)

Bodicoat, Danielle H; Carter, Patrice; Comber, Alexis; Edwardson, Charlotte; Gray, Laura J; Hill, Sian; Webb, David; Yates, Thomas; Davies, Melanie J; Khunti, Kamlesh

2015-06-01

We investigated whether a higher number of fast-food outlets in an individual's home neighbourhood is associated with increased prevalence of type 2 diabetes mellitus and related risk factors, including obesity. Cross-sectional study. Three UK-based diabetes screening studies (one general population, two high-risk populations) conducted between 2004 and 2011. The primary outcome was screen-detected type 2 diabetes. Secondary outcomes were risk factors for type 2 diabetes. In total 10 461 participants (mean age 59 years; 53% male; 21% non-White ethnicity). There was a higher number of neighbourhood (500 m radius from home postcode) fast-food outlets among non-White ethnic groups (Pfast-food outlets was associated with significantly increased odds for diabetes (OR=1.02; 95% CI 1.00, 1.04) and obesity (OR=1.02; 95% CI 1.00, 1.03). This suggests that for every additional two outlets per neighbourhood, we would expect one additional diabetes case, assuming a causal relationship between the fast-food outlets and diabetes. These results suggest that increased exposure to fast-food outlets is associated with increased risk of type 2 diabetes and obesity, which has implications for diabetes prevention at a public health level and for those granting planning permission to new fast-food outlets.

Screening for skin cancer.

Science.gov (United States)

Helfand, M; Mahon, S M; Eden, K B; Frame, P S; Orleans, C T

2001-04-01

Malignant melanoma is often lethal, and its incidence in the United States has increased rapidly over the past 2 decades. Nonmelanoma skin cancer is seldom lethal, but, if advanced, can cause severe disfigurement and morbidity. Early detection and treatment of melanoma might reduce mortality, while early detection and treatment of nonmelanoma skin cancer might prevent major disfigurement and to a lesser extent prevent mortality. Current recommendations from professional societies regarding screening for skin cancer vary. To examine published data on the effectiveness of routine screening for skin cancer by a primary care provider, as part of an assessment for the U.S. Preventive Services Task Force. We searched the MEDLINE database for papers published between 1994 and June 1999, using search terms for screening, physical examination, morbidity, and skin neoplasms. For information on accuracy of screening tests, we used the search terms sensitivity and specificity. We identified the most important studies from before 1994 from the Guide to Clinical Preventive Services, second edition, and from high-quality reviews. We used reference lists and expert recommendations to locate additional articles. Two reviewers independently reviewed a subset of 500 abstracts. Once consistency was established, the remainder were reviewed by one reviewer. We included studies if they contained data on yield of screening, screening tests, risk factors, risk assessment, effectiveness of early detection, or cost effectiveness. We abstracted the following descriptive information from full-text published studies of screening and recorded it in an electronic database: type of screening study, study design, setting, population, patient recruitment, screening test description, examiner, advertising targeted at high-risk groups or not targeted, reported risk factors of participants, and procedure for referrals. We also abstracted the yield of screening data including probabilities and numbers

CSBB-ConeExclusion, adapting structure based solution virtual screening to libraries on solid support.

Science.gov (United States)

Shave, Steven; Auer, Manfred

2013-12-23

Combinatorial chemical libraries produced on solid support offer fast and cost-effective access to a large number of unique compounds. If such libraries are screened directly on-bead, the speed at which chemical space can be explored by chemists is much greater than that addressable using solution based synthesis and screening methods. Solution based screening has a large supporting body of software such as structure-based virtual screening tools which enable the prediction of protein-ligand complexes. Use of these techniques to predict the protein bound complexes of compounds synthesized on solid support neglects to take into account the conjugation site on the small molecule ligand. This may invalidate predicted binding modes, the linker may be clashing with protein atoms. We present CSBB-ConeExclusion, a methodology and computer program which provides a measure of the applicability of solution dockings to solid support. Output is given in the form of statistics for each docking pose, a unique 2D visualization method which can be used to determine applicability at a glance, and automatically generated PyMol scripts allowing visualization of protein atom incursion into a defined exclusion volume. CSBB-ConeExclusion is then exemplarically used to determine the optimum attachment point for a purine library targeting cyclin-dependent kinase 2 CDK2.

A colorimetric assay of 1-aminocyclopropane-1-carboxylate (ACC) based on ninhydrin reaction for rapid screening of bacteria containing ACC deaminase.

Science.gov (United States)

Li, Z; Chang, S; Lin, L; Li, Y; An, Q

2011-08-01

1-Aminocyclopropane-1-carboxylate (ACC) deaminase activity is an efficient marker for bacteria to promote plant growth by lowering ethylene levels in plants. We aim to develop a method for rapidly screening bacteria containing ACC deaminase, based on a colorimetric ninhydrin assay of ACC. A reliable colorimetric ninhydrin assay was developed to quantify ACC using heat-resistant polypropylene chimney-top 96-well PCR plates, having the wells evenly heated in boiling water, preventing accidental contamination from boiling water and limiting evaporation. With this method to measure bacterial consumption of ACC, 44 ACC-utilizing bacterial isolates were rapidly screened out from 311 bacterial isolates that were able to grow on minimal media containing ACC as the sole nitrogen source. The 44 ACC-utilizing bacterial isolates showed ACC deaminase activities and belonged to the genus Burkholderia, Pseudomonas or Herbaspirillum. Determination of bacterial ACC consumption by the PCR-plate ninhydrin-ACC assay is a rapid and efficient method for screening bacteria containing ACC deaminase from a large number of bacterial isolates. The PCR-plate ninhydrin-ACC assay extends the utility of the ninhydrin reaction and enables a rapid screening of bacteria containing ACC deaminase from large numbers of bacterial isolates. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

Improving screening and diagnosis of exercise-induced bronchoconstriction: a call to action.

Science.gov (United States)

Weiler, John M; Hallstrand, Teal S; Parsons, Jonathan P; Randolph, Christopher; Silvers, William S; Storms, William W; Bronstone, Amy

2014-01-01

This article summarizes the findings of an expert panel of nationally recognized allergists and pulmonologists who met to discuss how to improve detection and diagnosis of exercise-induced bronchoconstriction (EIB), a transient airway narrowing that occurs during and most often after exercise in people with and without underlying asthma. EIB is both commonly underdiagnosed and overdiagnosed. EIB underdiagnosis may result in habitual avoidance of sports and physical activity, chronic deconditioning, weight gain, poor asthma control, low self-esteem, and reduced quality of life. Routine use of a reliable and valid self-administered EIB screening questionnaire by professionals best positioned to screen large numbers of people could substantially improve the detection of EIB. The authors conducted a systematic review of the literature that evaluated the accuracy of EIB screening questionnaires that might be adopted for widespread EIB screening in the general population. Results of this review indicated that no existing EIB screening questionnaire had adequate sensitivity and specificity for this purpose. The authors present a call to action to develop a new EIB screening questionnaire, and discuss the rigorous qualitative and quantitative research necessary to develop and validate such an instrument, including key methodological pitfalls that must be avoided. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

DRABAL: novel method to mine large high-throughput screening assays using Bayesian active learning

KAUST Repository

Soufan, Othman

2016-11-10

Background Mining high-throughput screening (HTS) assays is key for enhancing decisions in the area of drug repositioning and drug discovery. However, many challenges are encountered in the process of developing suitable and accurate methods for extracting useful information from these assays. Virtual screening and a wide variety of databases, methods and solutions proposed to-date, did not completely overcome these challenges. This study is based on a multi-label classification (MLC) technique for modeling correlations between several HTS assays, meaning that a single prediction represents a subset of assigned correlated labels instead of one label. Thus, the devised method provides an increased probability for more accurate predictions of compounds that were not tested in particular assays. Results Here we present DRABAL, a novel MLC solution that incorporates structure learning of a Bayesian network as a step to model dependency between the HTS assays. In this study, DRABAL was used to process more than 1.4 million interactions of over 400,000 compounds and analyze the existing relationships between five large HTS assays from the PubChem BioAssay Database. Compared to different MLC methods, DRABAL significantly improves the F1Score by about 22%, on average. We further illustrated usefulness and utility of DRABAL through screening FDA approved drugs and reported ones that have a high probability to interact with several targets, thus enabling drug-multi-target repositioning. Specifically DRABAL suggests the Thiabendazole drug as a common activator of the NCP1 and Rab-9A proteins, both of which are designed to identify treatment modalities for the Niemann–Pick type C disease. Conclusion We developed a novel MLC solution based on a Bayesian active learning framework to overcome the challenge of lacking fully labeled training data and exploit actual dependencies between the HTS assays. The solution is motivated by the need to model dependencies between existing

Detection of lung cancer through low-dose CT screening (NELSON): a prespecified analysis of screening test performance and interval cancers.

Science.gov (United States)

Horeweg, Nanda; Scholten, Ernst Th; de Jong, Pim A; van der Aalst, Carlijn M; Weenink, Carla; Lammers, Jan-Willem J; Nackaerts, Kristiaan; Vliegenthart, Rozemarijn; ten Haaf, Kevin; Yousaf-Khan, Uraujh A; Heuvelmans, Marjolein A; Thunnissen, Erik; Oudkerk, Matthijs; Mali, Willem; de Koning, Harry J

2014-11-01

Low-dose CT screening is recommended for individuals at high risk of developing lung cancer. However, CT screening does not detect all lung cancers: some might be missed at screening, and others can develop in the interval between screens. The NELSON trial is a randomised trial to assess the effect of screening with increasing screening intervals on lung cancer mortality. In this prespecified analysis, we aimed to assess screening test performance, and the epidemiological, radiological, and clinical characteristics of interval cancers in NELSON trial participants assigned to the screening group. Eligible participants in the NELSON trial were those aged 50-75 years, who had smoked 15 or more cigarettes per day for more than 25 years or ten or more cigarettes for more than 30 years, and were still smoking or had quit less than 10 years ago. We included all participants assigned to the screening group who had attended at least one round of screening. Screening test results were based on volumetry using a two-step approach. Initially, screening test results were classified as negative, indeterminate, or positive based on nodule presence and volume. Subsequently, participants with an initial indeterminate result underwent follow-up screening to classify their final screening test result as negative or positive, based on nodule volume doubling time. We obtained information about all lung cancer diagnoses made during the first three rounds of screening, plus an additional 2 years of follow-up from the national cancer registry. We determined epidemiological, radiological, participant, and tumour characteristics by reassessing medical files, screening CTs, and clinical CTs. The NELSON trial is registered at www.trialregister.nl, number ISRCTN63545820. 15,822 participants were enrolled in the NELSON trial, of whom 7915 were assigned to low-dose CT screening with increasing interval between screens, and 7907 to no screening. We included 7155 participants in our study, with

Design of Web Questionnaires : A Test for Number of Items per Screen

NARCIS (Netherlands)

Toepoel, V.; Das, J.W.M.; van Soest, A.H.O.

2005-01-01

This paper presents results from an experimental manipulation of one versus multiple-items per screen format in a Web survey.The purpose of the experiment was to find out if a questionnaire s format influences how respondents provide answers in online questionnaires and if this is depending on

Comparative analysis of mineral and secundary raw materials screening kinetics

Directory of Open Access Journals (Sweden)

Stojanović Aleksandra

2015-01-01

Full Text Available Efficiency of screening shows screening performance compared to an ideal screening to achieve a complete separation of the fractions without the presence of grains of size less than the mesh openings left on sieve and grains of size larger than the mesh opening that passed through the sieve. Efficiency is growing rapidly and after a certain time is reduced. This is explained by the fact that the speed of screening depends on the percentage of 'small', 'small-to large' and 'large' grain. The paper shows how for the given grain, their shape and density affect the kinetics of screening.

[Attendance rate in the Polish Cervical Cancer Screening Program in the years 2007-2009].

Science.gov (United States)

Spaczyński, Marek; Karowicz-Bilinska, Agata; Rokita, Wojciech; Molińska-Glura, Marta; Januszek-Michalecka, Lucyna; Seroczyński, Przemysław; Uchlik, Joanna; Nowak-Markwitz, Ewa

2010-09-01

for the years 2007, 2008 and 2009. The analysis included screening coverage in all voivodeships in the 12 months of the year as well as the number of gynaecological practices participating in the Program. In addition, the place of residence of screening attenders (urban/rural area) was taken into account. For the analysis the SIMP (System of Information Monitoring in Prophylaxis) data were used. Statistical analysis was performed using Statistica 9.0 software. P-values Program was the minimal value to observe a significant increase in the number of Pap smears collected (p = 0.000). Polish women do not attend screening in the winter months. However when a batch of invitations was sent in the spring or summer months, within two following months we could observe an increase in the number of Pap smears collected (p = 0.000). There are significant differences in the screening uptake in particular regions of Poland (a stable trend). Compared to urban women, rural women participate in the screening more often (p = 0.003). All Pap test results including opportunistic screening should be registered in the SIMP In the regions where particularly low attendance rates were observed, an intensive promotional campaign should be run to encourage participation in the screening. Also, sending a repeated invitation to non-compliers should be considered. The currently unfavorable schedule of invitation sending should be changed. According to the analysis performed, invitations should be more effective if sent on a regular basis (in small but regular batches), more intensively in the summer and spring months. In the winter season it would probably be better to focus on an extensive media campaign followed by sending a large number of personal invitations.

Addition of tomosynthesis to conventional digital mammography: effect on image interpretation time of screening examinations.

Science.gov (United States)

Dang, Pragya A; Freer, Phoebe E; Humphrey, Kathryn L; Halpern, Elkan F; Rafferty, Elizabeth A

2014-01-01

To determine the effect of implementing a screening tomosynthesis program on real-world clinical performance by quantifying differences between interpretation times for conventional screening mammography and combined tomosynthesis and mammography for multiple participating radiologists with a wide range of experience in a large academic center. In this HIPAA-compliant, institutional review board-approved study, 10 radiologists prospectively read images from screening digital mammography or screening combined tomosynthesis and mammography examinations for 1-hour-long uninterrupted sessions. Images from 3665 examinations (1502 combined and 2163 digital mammography) from July 2012 to January 2013 were interpreted in at least five sessions per radiologist per modality. The number of cases reported during each session was recorded for each reader. The experience level for each radiologist was also correlated to the average number of cases reported per hour. Analysis of variance was used to assess the number of studies interpreted per hour. A linear regression model was used to evaluate correlation between breast imaging experience and time taken to interpret images from both modalities. The mean number of studies interpreted in hour was 23.8 ± 0.55 (standard deviation) (range, 14.4-40.4) for combined tomosynthesis and mammography and 34.0 ± 0.55 (range, 20.4-54.3) for digital mammography alone. A mean of 10.2 fewer studies were interpreted per hour during combined tomosynthesis and mammography compared with digital mammography sessions (P tomosynthesis and mammography and 1.9 minutes ± 0.6 (range, 1.1-3.0) for digital mammography; interpretation time with combined tomosynthesis and mammography was 0.9 minute longer (47% longer) compared with digital mammography alone (P tomosynthesis and mammography examinations decreased (R(2) = 0.52, P = .03). Addition of tomosynthesis to mammography results in increased time to interpret images from screening examinations compared

Multi-type Step-wise group screening designs with unequal A-priori ...

African Journals Online (AJOL)

... design with unequal group sizes and obtain values of the group sizes that minimize the expected number of runs.. Keywords: Group Screening, Group factors, multi-type step-wise group screening, expected number of runs, Optimum group screening designs > East African Journal of Statistics Vol. 1 (1) 2005: pp. 49-67 ...

On the Required Number of Antennas in a Point-to-Point Large-but-Finite MIMO System

KAUST Repository

Makki, Behrooz; Svensson, Tommy; Eriksson, Thomas; Alouini, Mohamed-Slim

2015-01-01

In this paper, we investigate the performance of the point-to-point multiple-input-multiple-output (MIMO) systems in the presence of a large but finite numbers of antennas at the transmitters and/or receivers. Considering the cases with and without hybrid automatic repeat request (HARQ) feedback, we determine the minimum numbers of the transmit/receive antennas which are required to satisfy different outage probability constraints. We study the effect of the spatial correlation between the antennas on the system performance. Also, the required number of antennas are obtained for different fading conditions. Our results show that different outage requirements can be satisfied with relatively few transmit/receive antennas. © 2015 IEEE.

On the Required Number of Antennas in a Point-to-Point Large-but-Finite MIMO System

KAUST Repository

Makki, Behrooz

2015-11-12

In this paper, we investigate the performance of the point-to-point multiple-input-multiple-output (MIMO) systems in the presence of a large but finite numbers of antennas at the transmitters and/or receivers. Considering the cases with and without hybrid automatic repeat request (HARQ) feedback, we determine the minimum numbers of the transmit/receive antennas which are required to satisfy different outage probability constraints. We study the effect of the spatial correlation between the antennas on the system performance. Also, the required number of antennas are obtained for different fading conditions. Our results show that different outage requirements can be satisfied with relatively few transmit/receive antennas. © 2015 IEEE.

Interval Cancers in a Population-Based Screening Program for Colorectal Cancer in Catalonia, Spain

Directory of Open Access Journals (Sweden)

M. Garcia

2015-01-01

Full Text Available Objective. To analyze interval cancers among participants in a screening program for colorectal cancer (CRC during four screening rounds. Methods. The study population consisted of participants of a fecal occult blood test-based screening program from February 2000 to September 2010, with a 30-month follow-up (n = 30,480. We used hospital administration data to identify CRC. An interval cancer was defined as an invasive cancer diagnosed within 30 months of a negative screening result and before the next recommended examination. Gender, age, stage, and site distribution of interval cancers were compared with those in the screen-detected group. Results. Within the study period, 97 tumors were screen-detected and 74 tumors were diagnosed after a negative screening. In addition, 17 CRC (18.3% were found after an inconclusive result and 2 cases were diagnosed within the surveillance interval (2.1%. There was an increase of interval cancers over the four rounds (from 32.4% to 46.0%. When compared with screen-detected cancers, interval cancers were found predominantly in the rectum (OR: 3.66; 95% CI: 1.51–8.88 and at more advanced stages (P=0.025. Conclusion. There are large numbers of cancer that are not detected through fecal occult blood test-based screening. The low sensitivity should be emphasized to ensure that individuals with symptoms are not falsely reassured.

Obstructions to the realization of distance graphs with large chromatic numbers on spheres of small radii

Energy Technology Data Exchange (ETDEWEB)

Kupavskii, A B; Raigorodskii, A M [M. V. Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Moscow (Russian Federation)

2013-10-31

We investigate in detail some properties of distance graphs constructed on the integer lattice. Such graphs find wide applications in problems of combinatorial geometry, in particular, such graphs were employed to answer Borsuk's question in the negative and to obtain exponential estimates for the chromatic number of the space. This work is devoted to the study of the number of cliques and the chromatic number of such graphs under certain conditions. Constructions of sequences of distance graphs are given, in which the graphs have unit length edges and contain a large number of triangles that lie on a sphere of radius 1/√3 (which is the minimum possible). At the same time, the chromatic numbers of the graphs depend exponentially on their dimension. The results of this work strengthen and generalize some of the results obtained in a series of papers devoted to related issues. Bibliography: 29 titles.

Screening for colorectal cancer: what fits best?

LENUS (Irish Health Repository)

Lee, Chun Seng

2012-06-01

Colorectal cancer (CRC) screening has been shown to be effective in reducing CRC incidence and mortality. There are currently a number of screening modalities available for implementation into a population-based CRC screening program. Each screening method offers different strengths but also possesses its own limitations as a population-based screening strategy. We review the current evidence base for accepted CRC screening tools and evaluate their merits alongside their challenges in fulfilling their role in the detection of CRC. We also aim to provide an outlook on the demands of a low-risk population-based CRC screening program with a view to providing insight as to which modality would best suit current and future needs.

Recreating Raven's: software for systematically generating large numbers of Raven-like matrix problems with normed properties.

Science.gov (United States)

Matzen, Laura E; Benz, Zachary O; Dixon, Kevin R; Posey, Jamie; Kroger, James K; Speed, Ann E

2010-05-01

Raven's Progressive Matrices is a widely used test for assessing intelligence and reasoning ability (Raven, Court, & Raven, 1998). Since the test is nonverbal, it can be applied to many different populations and has been used all over the world (Court & Raven, 1995). However, relatively few matrices are in the sets developed by Raven, which limits their use in experiments requiring large numbers of stimuli. For the present study, we analyzed the types of relations that appear in Raven's original Standard Progressive Matrices (SPMs) and created a software tool that can combine the same types of relations according to parameters chosen by the experimenter, to produce very large numbers of matrix problems with specific properties. We then conducted a norming study in which the matrices we generated were compared with the actual SPMs. This study showed that the generated matrices both covered and expanded on the range of problem difficulties provided by the SPMs.

Using the Larval Zebrafish Locomotor Assay in Functional Neurotoxicity Screening: Light Intensity and the Order of Stimulus Presentation Affect the Outcome

Science.gov (United States)

The U.S. Environmental Protection Agency is evaluating methods to screen and prioritize large numbers of chemicals using 6 day old zebrafish (Danio rerio) as an alternative test model for detecting neurotoxic chemicals. We use a behavioral testing paradigm that simultaneously tes...

Data-Driven Derivation of an "Informer Compound Set" for Improved Selection of Active Compounds in High-Throughput Screening.

Science.gov (United States)

Paricharak, Shardul; IJzerman, Adriaan P; Jenkins, Jeremy L; Bender, Andreas; Nigsch, Florian

2016-09-26

Despite the usefulness of high-throughput screening (HTS) in drug discovery, for some systems, low assay throughput or high screening cost can prohibit the screening of large numbers of compounds. In such cases, iterative cycles of screening involving active learning (AL) are employed, creating the need for smaller "informer sets" that can be routinely screened to build predictive models for selecting compounds from the screening collection for follow-up screens. Here, we present a data-driven derivation of an informer compound set with improved predictivity of active compounds in HTS, and we validate its benefit over randomly selected training sets on 46 PubChem assays comprising at least 300,000 compounds and covering a wide range of assay biology. The informer compound set showed improvement in BEDROC(α = 100), PRAUC, and ROCAUC values averaged over all assays of 0.024, 0.014, and 0.016, respectively, compared to randomly selected training sets, all with paired t-test p-values agnostic fashion. This approach led to a consistent improvement in hit rates in follow-up screens without compromising scaffold retrieval. The informer set is adjustable in size depending on the number of compounds one intends to screen, as performance gains are realized for sets with more than 3,000 compounds, and this set is therefore applicable to a variety of situations. Finally, our results indicate that random sampling may not adequately cover descriptor space, drawing attention to the importance of the composition of the training set for predicting actives.

Fragment-based screening in tandem with phenotypic screening provides novel antiparasitic hits.

Science.gov (United States)

Blaazer, Antoni R; Orrling, Kristina M; Shanmugham, Anitha; Jansen, Chimed; Maes, Louis; Edink, Ewald; Sterk, Geert Jan; Siderius, Marco; England, Paul; Bailey, David; de Esch, Iwan J P; Leurs, Rob

2015-01-01

Methods to discover biologically active small molecules include target-based and phenotypic screening approaches. One of the main difficulties in drug discovery is elucidating and exploiting the relationship between drug activity at the protein target and disease modification, a phenotypic endpoint. Fragment-based drug discovery is a target-based approach that typically involves the screening of a relatively small number of fragment-like (molecular weight <300) molecules that efficiently cover chemical space. Here, we report a fragment screening on TbrPDEB1, an essential cyclic nucleotide phosphodiesterase (PDE) from Trypanosoma brucei, and human PDE4D, an off-target, in a workflow in which fragment hits and a series of close analogs are subsequently screened for antiparasitic activity in a phenotypic panel. The phenotypic panel contained T. brucei, Trypanosoma cruzi, Leishmania infantum, and Plasmodium falciparum, the causative agents of human African trypanosomiasis (sleeping sickness), Chagas disease, leishmaniasis, and malaria, respectively, as well as MRC-5 human lung cells. This hybrid screening workflow has resulted in the discovery of various benzhydryl ethers with antiprotozoal activity and low toxicity, representing interesting starting points for further antiparasitic optimization. © 2014 Society for Laboratory Automation and Screening.

Assessing the use of digital radiography and a real-time interactive pulmonary nodule analysis system for large population lung cancer screening

International Nuclear Information System (INIS)

Xu Yan; Ma Daqing; He Wen

2012-01-01

Rationale and objectives: To assess the use of chest digital radiograph (DR) assisted with a real-time interactive pulmonary nodule analysis system in large population lung cancer screening. Materials and methods: 346 DR/CR patient studies with corresponding CT images were selected from 12,500 patients screened for lung cancer from year 2007 to 2009. Two expert chest radiologists established CT-confirmed Gold Standard of nodules on DR/CR images with consensus. These cases were read by eight other chest radiologists (participating radiologists) first without using a real-time interactive pulmonary nodule analysis system and then re-read using the system. Performances of participating radiologists and the computer system were analyzed. Results: The computer system achieved similar performance on DR and CR images, with a detection rate of 76% and an average FPs of 2.0 per image. Before and after using the computer-aided detection system, the nodule detection sensitivities of the participating radiologists were 62.3% and 77.3% respectively, and the A z values increased from 0.794 to 0.831. Statistical analysis demonstrated statically significant improvement for the participating radiologists after using the computer analysis system with a P-value 0.05. Conclusion: The computer system could help radiologists identify more lesions, especially small ones that are more likely to be overlooked on chest DR/CR images, and could help reduce inter-observer diagnostic variations, while its FPs were easy to recognize and dismiss. It is suggested that DR/CR assisted by the real-time interactive pulmonary nodule analysis system may be an effective means to screen large populations for lung cancer.

Malnutrition risk in hospitalized children: use of 3 screening tools in a large European population.

Science.gov (United States)

Chourdakis, Michael; Hecht, Christina; Gerasimidis, Konstantinos; Joosten, Koen Fm; Karagiozoglou-Lampoudi, Thomais; Koetse, Harma A; Ksiazyk, Janusz; Lazea, Cecilia; Shamir, Raanan; Szajewska, Hania; Koletzko, Berthold; Hulst, Jessie M

2016-05-01

Several malnutrition screening tools have been advocated for use in pediatric inpatients. We evaluated how 3 popular pediatric nutrition screening tools [i.e., the Pediatric Yorkhill Malnutrition Score (PYMS), the Screening Tool for the Assessment of Malnutrition in Pediatrics (STAMP), and the Screening Tool for Risk of Impaired Nutritional Status and Growth (STRONGKIDS)] compared with and were related to anthropometric measures, body composition, and clinical variables in patients who were admitted to tertiary hospitals across Europe. The 3 screening tools were applied in 2567 inpatients at 14 hospitals across 12 European countries. The classification of patients into different nutritional risk groups was compared between tools and related to anthropometric measures and clinical variables [e.g., length of hospital stay (LOS) and infection rates]. A similar rate of completion of the screening tools for each tool was achieved (PYMS: 86%; STAMP: 84%; and STRONGKIDS: 81%). Risk classification differed markedly by tool, with an overall agreement of 41% between tools. Children categorized as high risk (PYMS: 25%; STAMP: 23%; and STRONGKIDS: 10%) had a longer LOS than that of children at low risk (1.4, 1.4, and 1.8 d longer, respectively; P malnutrition risk varied across the pediatric tools used. A considerable portion of children with subnormal anthropometric measures were not identified with all of the tools. The data obtained do not allow recommending the use of any of these screening tools for clinical practice. This study was registered at clinicaltrials.gov as NCT01132742. © 2016 American Society for Nutrition.

Cervical cancer screening in Australia: modelled evaluation of the impact of changing the recommended interval from two to three years

Directory of Open Access Journals (Sweden)

Howard Kirsten

2010-11-01

cost savings are predicted to be of the order of A$10-18 M annually, equivalent to 6-11% of the total cost of the current program (excluding overheads, with call-and-recall being associated with the greatest savings. Conclusions Lengthening the recommended screening interval to 3 years in Australia is not predicted to result in increases in rates of cervical cancer and is predicted to decrease the number of women undergoing diagnostic and treatment procedures. These findings are consistent with a large body of international evidence showing that screening more frequently than every three years with cervical cytology does not result in substantial gains in screening effectiveness.

Study on impurity screening in stochastic magnetic boundary of the Large Helical Device

International Nuclear Information System (INIS)

Kobayashi, M.; Morita, S.; Feng, Y.

2008-10-01

The impurity transport characteristics in the scrape-off layer associated with a stochastic magnetic boundary of LHD are analyzed. The remnant islands with very small internal field line pitch in the stochastic region play a key role in reducing the impurity influx. The thermal force driven impurity influx is significantly suppressed when the perpendicular energy flux exceeds the parallel one inside the islands due to the small pitch. Application of the 3D edge transport code, EMC3-EIRENE, confirmed the impurity retention (screening) effect in the edge region. It is also found that the edge surface layers are the most effective region to retain (screen) impurities because of the flow acceleration and plasma cooling via short flux tubes. The carbon emission obtained in experiments is in good agreement with the modelling results, showing the impurity retention (screening) potential of the stochastic magnetic boundary. (author)

Active Learning Strategies for Phenotypic Profiling of High-Content Screens.

Science.gov (United States)

Smith, Kevin; Horvath, Peter

2014-06-01

High-content screening is a powerful method to discover new drugs and carry out basic biological research. Increasingly, high-content screens have come to rely on supervised machine learning (SML) to perform automatic phenotypic classification as an essential step of the analysis. However, this comes at a cost, namely, the labeled examples required to train the predictive model. Classification performance increases with the number of labeled examples, and because labeling examples demands time from an expert, the training process represents a significant time investment. Active learning strategies attempt to overcome this bottleneck by presenting the most relevant examples to the annotator, thereby achieving high accuracy while minimizing the cost of obtaining labeled data. In this article, we investigate the impact of active learning on single-cell-based phenotype recognition, using data from three large-scale RNA interference high-content screens representing diverse phenotypic profiling problems. We consider several combinations of active learning strategies and popular SML methods. Our results show that active learning significantly reduces the time cost and can be used to reveal the same phenotypic targets identified using SML. We also identify combinations of active learning strategies and SML methods which perform better than others on the phenotypic profiling problems we studied. © 2014 Society for Laboratory Automation and Screening.

New feature for an old large number

International Nuclear Information System (INIS)

Novello, M.; Oliveira, L.R.A.

1986-01-01

A new context for the appearance of the Eddington number (10 39 ), which is due to the examination of elastic scattering of scalar particles (ΠK → ΠK) non-minimally coupled to gravity, is presented. (author) [pt

Latent fingerprints on different type of screen protective films

Directory of Open Access Journals (Sweden)

Yuttana Sudjaroen

2016-07-01

Full Text Available The purpose of this research was to study the quality of latent fingerprint on different types of screen protective films including screen protector, matte screen protector, anti-fingerprint clear screen protector and anti-fingerprint matte screen protector by using black powder method in developing latent fingerprints. The fingerprints were performed by 10 volunteers whose fingers (right index, right thumb, left index and left thumb were stubbing at different types of screen protective films and subsequently latent fingerprints were developed by brushing with black powder. Automated Fingerprint Identification System (AFIS counted the numbers of minutiae points from 320 latent fingerprints. Anti-fingerprint matte screen protective film produced the best quality of latent fingerprint with an average minutiae point 72.65, followed by matte screen protective film, clear screen protective film and anti-fingerprint clear screen protective film with an average minutiae point of 155.2, 135.0 and 72.65 respectively. The quality of latent fingerprints developed between a clear and a matte surface of screen protective films showed a significant difference (sig>0.05, whereas the coat and the non-coat with anti-fingerprint chemical revealed a non-significant difference (sig<0.05 in their number of minutiae points.

Market screening of natural gas reformers

International Nuclear Information System (INIS)

Themsen, J.; Pagh Nielsen, M.; Knudsen Kaer, S.

2005-01-01

This report presents results from the project: Market screening of natural gas reformers. The project objective was to screen the natural gas reformers available on the international market. The technology is developing rapidly, and the results from this project will assist in determining the focus for the future Danish activities and in setting up ambitious and realistic targets. The reformer screening is partly based on AAU and Dantherm's experiences from previous studies, and the screening has been further extended with a number of activities, including seminars and contact with some of the most interesting suppliers. (BA)

Screening survey on thyroid exposure for children after the Fukushima Daiichi Nuclear Power Station accident

Energy Technology Data Exchange (ETDEWEB)

Kim, Eunjoo; Kurihara, Osamu; Suzuki, Toshikazu; Matsumoto, Masaki; Fukutsu, Kumiko; Yamada, Yuji; Sugiura, Nobuyuki; Akashi, Makoto [National Institute of Radiological Sciences, Research Center for Radiation Emergency Medicine, Chiba, Chiba (Japan)

2012-11-15

In response to a serious accident at the Fukushima Daiichi Nuclear Power Station, National Institute of Radiological Sciences (NIRS) established a protocol for a screening survey of thyroid exposure for children living in areas where thyroid doses were predicted to be high. The aim of the screening survey was to implement measurements for a large number of subjects with conventional NaI(Tl) scintillation survey meters. This protocol was applied to the screening survey of 1,149 children at five locations in three municipalities (Kawamata Town, Iitate Village and Iwaki City). Among 1,080 children (excluding 69 subjects from evaluation), there were no subjects who exceeded a screening level (0.2 {mu}Sv h{sup -1}) corresponding to a thyroid equivalent dose of 100 mSv (for the age group of 1-y-old as of March 24). No significant signals were detected in 55.4% of these subjects and the maximum dose was found to be 43 mSv. This paper presents details on the protocol as well as results of the screening survey. (author)

Thyroid screening of members of the public for iodine isotopes with portable NaI detectors

International Nuclear Information System (INIS)

Hunt, John G.

2014-01-01

In the case of an accident in a nuclear power plant with radionuclide releases to the environment, members of the public with possible internal contamination with radioactive isotopes of iodine should be screened to identify cases where a more detailed evaluation and medical follow-up is necessary. Screening of large numbers of the public can be performed with a quick measuring protocol using hand held unshielded NaI based detectors giving results in cps. The screening geometry was simulated using the Monte Carlo code Visual Monte Carlo. The results show that for a geometry with the NaI detector near the skin in front of the thyroid, the interference of the gamma radiation coming from other radionuclides released in the accident either deposited in the lung or in the whole body is sufficiently low to allow thyroid screening criteria to be established. The screening criteria were developed using 5, 10 and 15 year old hybrid phantoms and for the adult male based on the ICRP reference voxel phantom. (author)

Wall modeled large eddy simulations of complex high Reynolds number flows with synthetic inlet turbulence

International Nuclear Information System (INIS)

Patil, Sunil; Tafti, Danesh

2012-01-01

Highlights: ► Large eddy simulation. ► Wall layer modeling. ► Synthetic inlet turbulence. ► Swirl flows. - Abstract: Large eddy simulations of complex high Reynolds number flows are carried out with the near wall region being modeled with a zonal two layer model. A novel formulation for solving the turbulent boundary layer equation for the effective tangential velocity in a generalized co-ordinate system is presented and applied in the near wall zonal treatment. This formulation reduces the computational time in the inner layer significantly compared to the conventional two layer formulations present in the literature and is most suitable for complex geometries involving body fitted structured and unstructured meshes. The cost effectiveness and accuracy of the proposed wall model, used with the synthetic eddy method (SEM) to generate inlet turbulence, is investigated in turbulent channel flow, flow over a backward facing step, and confined swirling flows at moderately high Reynolds numbers. Predictions are compared with available DNS, experimental LDV data, as well as wall resolved LES. In all cases, there is at least an order of magnitude reduction in computational cost with no significant loss in prediction accuracy.

[Organized breast cancer screening].

Science.gov (United States)

Rouëssé, Jacques; Sancho-Garnier, Hélèn

2014-02-01

Breast screening programs are increasingly controversial, especially regarding two points: the number of breast cancer deaths they avoid, and the problem of over-diagnosis and over-treatment. The French national breast cancer screening program was extended to cover the whole country in 2004. Ten years later it is time to examine the risk/benefit ratio of this program and to discuss the need for change. Like all forms of cancer management, screening must be regularly updated, taking into account the state of the art, new evidence, and uncertainties. All screening providers should keep themselves informed of the latest findings. In the French program, women aged 50-74 with no major individual or familial risk factors for breast cancer are offered screening mammography and clinical breast examination every two years. Images considered non suspicious of malignancy by a first reader are re-examined by a second reader. The devices and procedures are subjected to quality controls. Participating radiologists (both public and private) are required to read at least 500 mammographies per year. The program's national participation rate was 52.7 % in 2012. When individual screening outside of the national program is taken into account (nearly 15 % of women), coverage appears close to the European recommendation of 65 %. Breast cancer mortality has been falling in France by 0.6 % per year for over 30 years, starting before mass screening was implemented, and by 1.5 % since 2005. This decline can be attributed in part to earlier diagnosis and better treatment, so that the specific impact of screening cannot easily be measured. Over-treatment, defined as the detection and treatment of low-malignancy tumors that would otherwise not have been detected in a person's lifetime, is a major negative effect of screening, but its frequency is not precisely known (reported to range from 1 % to 30 %). In view of these uncertainties, it would be advisable to modify the program in order to

Implementing a Fee-for-Service Cervical Cancer Screening and Treatment Program in Cameroon: Challenges and Opportunities.

Science.gov (United States)

DeGregorio, Geneva; Manga, Simon; Kiyang, Edith; Manjuh, Florence; Bradford, Leslie; Cholli, Preetam; Wamai, Richard; Ogembo, Rebecca; Sando, Zacharie; Liu, Yuxin; Sheldon, Lisa Kennedy; Nulah, Kathleen; Welty, Thomas; Welty, Edith; Ogembo, Javier Gordon

2017-07-01

Cervical cancer screening is one of the most effective cancer prevention strategies, but most women in Africa have never been screened. In 2007, the Cameroon Baptist Convention Health Services, a large faith-based health care system in Cameroon, initiated the Women's Health Program (WHP) to address this disparity. The WHP provides fee-for-service cervical cancer screening using visual inspection with acetic acid enhanced by digital cervicography (VIA-DC), prioritizing care for women living with HIV/AIDS. They also provide clinical breast examination, family planning (FP) services, and treatment for reproductive tract infection (RTI). Here, we document the strengths and challenges of the WHP screening program and the unique aspects of the WHP model, including a fee-for-service payment system and the provision of other women's health services. We retrospectively reviewed WHP medical records from women who presented for cervical cancer screening from 2007-2014. In 8 years, WHP nurses screened 44,979 women for cervical cancer. The number of women screened increased nearly every year. The WHP is sustained primarily on fees-for-service, with external funding totaling about $20,000 annually. In 2014, of 12,191 women screened for cervical cancer, 99% received clinical breast exams, 19% received FP services, and 4.7% received treatment for RTIs. We document successes, challenges, solutions implemented, and recommendations for optimizing this screening model. The WHP's experience using a fee-for-service model for cervical cancer screening demonstrates that in Cameroon VIA-DC is acceptable, feasible, and scalable and can be nearly self-sustaining. Integrating other women's health services enabled women to address additional health care needs. The Cameroon Baptist Convention Health Services Women's Health Program successfully implemented a nurse-led, fee-for-service cervical cancer screening program using visual inspection with acetic acid-enhanced by digital cervicography in

Automated microscopy for high-content RNAi screening

Science.gov (United States)

2010-01-01

Fluorescence microscopy is one of the most powerful tools to investigate complex cellular processes such as cell division, cell motility, or intracellular trafficking. The availability of RNA interference (RNAi) technology and automated microscopy has opened the possibility to perform cellular imaging in functional genomics and other large-scale applications. Although imaging often dramatically increases the content of a screening assay, it poses new challenges to achieve accurate quantitative annotation and therefore needs to be carefully adjusted to the specific needs of individual screening applications. In this review, we discuss principles of assay design, large-scale RNAi, microscope automation, and computational data analysis. We highlight strategies for imaging-based RNAi screening adapted to different library and assay designs. PMID:20176920

Relationship between prostate-specific antigen and obesity in prostate cancer screening: analysis of a large cohort in Japan.

Science.gov (United States)

Kubota, Yasuaki; Seike, Kensaku; Maeda, Shinichi; Shinohara, Yuka; Iwata, Masamitsu; Sugimoto, Norio

2011-01-01

Previous studies have shown that lower prostate-specific antigen (PSA) levels in obese men might decrease the sensitivity of prostate cancer screening, leading to delayed diagnosis and unfavorable prognosis. We examined whether the effect of obesity is important in prostate cancer screening of Japanese men, who have a low prevalence of obesity. We analyzed 19,294 male subjects from a large cohort of Toyota Motor Corporation (TMC) employees (aged > 50 years, serum PSA level ≤ 4.0 ng/mL) who underwent physical examinations from August 2006 to December 2009. The relationship between PSA level and obesity-related factors was analyzed by simple and multiple regression analysis. The relationships between six body mass index (BMI) categories, and PSA level and PSA mass (PSA concentration × plasma volume) were analyzed. PSA level decreased significantly with increasing BMI, but the coefficient of determination was very low. Mean PSA values decreased from 1.02 to 0.85 ng/mL as BMI increased from underweight (BMI 35). However, PSA mass peaked in the overweight category and was slightly reduced with increasing BMI. On multiple regression analysis, PSA level was influenced by age, diastolic blood pressure and high-density lipoprotein as well as BMI. We found an inverse but weak relationship between PSA level and BMI. Obesity seems to have very limited influence on prostate cancer screening in this population. Nonetheless, when considering indications for prostatic biopsy in obese men, we should be aware that the hemodilution effect might reduce PSA levels. © 2010 The Japanese Urological Association.

Prior Radiological Investigations in 65-Year-Old Men Screened for AAA.

Science.gov (United States)

Meecham, Lewis; Summerour, Virginia; Hobbs, Simon; Newman, Jeremy; Wall, Michael L

2018-05-01

The National Health Service abdominal aortic aneurysm screening programme (NAAASP) is now fully operational. Those who have previously been formally investigated for abdominal aortic aneurysm (AAA) are excluded; however, many patients undergo radiological investigation of the abdomen for other reasons. Such practices may find incidental AAA which may be eroding the performance of the NAAASP. We investigated the rates of preinvestigation before invitation to screening in our local AAA screening programme. Electronic patient records were retrospectively reviewed for all patients called between March 2013 and February 2016 in 1 local AAA screening programme. Their records were interrogated to identify any abdominal imaging within 5 years of their invitation to screening. Two thousand six hundred thirty-eight men were invited for screening; of these, 563 (21.3%) had been "prescreened". Median time between prescreening and screening was 19 months (0-60 months). Ultrasound abdomen was the most prevalent at 248 (44.0%). Two thousand two hundred forty-three (85.0%) men attended screening, and 6 (0.27%) were excluded for known AAA. Prevalence of AAA was 1.8% (n = 41). Of these, 15 (36.6%) had prior investigation with 6 (40.0%) having AAA diagnosed. Therefore, 9 (22.0%) had potential missed AAA on "prescreening" (mean diameter 35 mm [30-45], mean time lapse between investigation and screening 21.1 months [1-49]). Incidence of missed aneurysm in the "prescreened" cohort was 1.6% (9/563). Large numbers of men invited for AAA screening have undergone preinvestigation of their abdominal aorta, with 60% of the present AAA being missed. Reliance on incidental detection of AAA would leave many patients undiagnosed in the community-at risk of future rupture. Copyright © 2018 Elsevier Inc. All rights reserved.

Breast cancer screening-opportunistic use of registry and linked screening data for local evaluation.

Science.gov (United States)

Roder, David; Farshid, Gelareh; Gill, Grantley; Kollias, Jim; Koczwara, Bogda; Karapetis, Chris; Adams, Jacqui; Joshi, Rohit; Keefe, Dorothy; Powell, Kate; Fusco, Kellie; Eckert, Marion; Buckley, Elizabeth; Beckmann, Kerri

2017-06-01

Screening has been found to reduce breast cancer mortality at a population level in Australia, but these studies did not address local settings where numbers of deaths would generally have been too low for evaluation. Clinicians, administrators, and consumer groups are also interested in local service outcomes. We therefore use more common prognostic and treatment measures and survivals to gain evidence of screening effects among patients attending 4 local hospitals for treatment. To compare prognostic, treatment, and survival measures by screening history to determine whether expected screening effects are occurring. Employing routine clinical registry and linked screening data to investigate associations of screening history with these measures, using unadjusted and adjusted analyses. Screened women had a 10-year survival from breast cancer of 92%, compared with 78% for unscreened women; and 79% of screened surgical cases had breast conserving surgery compared with 64% in unscreened women. Unadjusted analyses indicated that recently screened cases had earlier tumor node metastasis stages, smaller diameters, less nodal involvement, better tumor differentiation, more oestrogen and progesterone receptor positive lesions, more hormone therapy, and less chemotherapy. Radiotherapy tended to be more common in screening participants. More frequent use of adjunctive radiotherapy applied when breast conserving surgery was used. Results confirm the screening effects expected from the scientific literature and demonstrate the value of opportunistic use of available registry and linked screening data for indicating to local health administrations, practitioners, and consumers whether local screening services are having the effects expected. © 2016 John Wiley & Sons, Ltd.

Fabrication of digital microfluidic devices on flexible paper-based and rigid substrates via screen printing

Science.gov (United States)

Yafia, Mohamed; Shukla, Saurabh; Najjaran, Homayoun

2015-05-01

In this work, a new fabrication method is presented for digital microfluidic (DMF) devices in which the electrodes are generated using the screen printing technique. This method is applicable to both rigid and flexible substrates. The proposed screen printing approach, as a batch printing technique, is advantageous to the widely reported DMF fabrication methods in terms of fabrication time, cost and capability of mass production. Screen printing provides an effective means for printing different types of conductive materials on a variety of substrates. Specifically, screen printing of conductive silver and carbon based inks is performed on paper, glass and wax paper. As a result, the fabricated DMF devices are characterized by being flexible, disposable and incinerable. Hence, the main advantage of screen printing carbon based inks on paper substrates is more pronounced for point-of-care applications that require a large number of low cost DMF chips, and laboratory setups that lack sophisticated microfabrication facilities. The resolution of the printed DMF electrodes generated by this technique is examined for proof of concept using manual screen printing, but higher resolution screens and automated machines are available off-the-shelf, if needed. Another contribution of this research is the improved actuation techniques that facilitate droplet transport in electrode configurations with relatively large electrode spacing to alleviate the disadvantage of lower resolution screens. Thus, we were able to reduce the cost of fabrication significantly without compromising the DMF performance. The paper-based devices have already shown to be effective in continuous microfluidics domain, so the investigation of their applicability in DMF systems is worthwhile. With this in mind, successful integration of a paper-based microchannel with paper-based digital microfluidic chip is demonstrated in this work.

Fabrication of digital microfluidic devices on flexible paper-based and rigid substrates via screen printing

International Nuclear Information System (INIS)

Yafia, Mohamed; Shukla, Saurabh; Najjaran, Homayoun

2015-01-01

In this work, a new fabrication method is presented for digital microfluidic (DMF) devices in which the electrodes are generated using the screen printing technique. This method is applicable to both rigid and flexible substrates. The proposed screen printing approach, as a batch printing technique, is advantageous to the widely reported DMF fabrication methods in terms of fabrication time, cost and capability of mass production. Screen printing provides an effective means for printing different types of conductive materials on a variety of substrates. Specifically, screen printing of conductive silver and carbon based inks is performed on paper, glass and wax paper. As a result, the fabricated DMF devices are characterized by being flexible, disposable and incinerable. Hence, the main advantage of screen printing carbon based inks on paper substrates is more pronounced for point-of-care applications that require a large number of low cost DMF chips, and laboratory setups that lack sophisticated microfabrication facilities. The resolution of the printed DMF electrodes generated by this technique is examined for proof of concept using manual screen printing, but higher resolution screens and automated machines are available off-the-shelf, if needed. Another contribution of this research is the improved actuation techniques that facilitate droplet transport in electrode configurations with relatively large electrode spacing to alleviate the disadvantage of lower resolution screens. Thus, we were able to reduce the cost of fabrication significantly without compromising the DMF performance. The paper-based devices have already shown to be effective in continuous microfluidics domain, so the investigation of their applicability in DMF systems is worthwhile. With this in mind, successful integration of a paper-based microchannel with paper-based digital microfluidic chip is demonstrated in this work. (note)

Random number generators for large-scale parallel Monte Carlo simulations on FPGA

Science.gov (United States)

Lin, Y.; Wang, F.; Liu, B.

2018-05-01

Through parallelization, field programmable gate array (FPGA) can achieve unprecedented speeds in large-scale parallel Monte Carlo (LPMC) simulations. FPGA presents both new constraints and new opportunities for the implementations of random number generators (RNGs), which are key elements of any Monte Carlo (MC) simulation system. Using empirical and application based tests, this study evaluates all of the four RNGs used in previous FPGA based MC studies and newly proposed FPGA implementations for two well-known high-quality RNGs that are suitable for LPMC studies on FPGA. One of the newly proposed FPGA implementations: a parallel version of additive lagged Fibonacci generator (Parallel ALFG) is found to be the best among the evaluated RNGs in fulfilling the needs of LPMC simulations on FPGA.

Cost-effectiveness of breast cancer screening policies using simulation.

Science.gov (United States)

Gocgun, Y; Banjevic, D; Taghipour, S; Montgomery, N; Harvey, B J; Jardine, A K S; Miller, A B

2015-08-01

In this paper, we study breast cancer screening policies using computer simulation. We developed a multi-state Markov model for breast cancer progression, considering both the screening and treatment stages of breast cancer. The parameters of our model were estimated through data from the Canadian National Breast Cancer Screening Study as well as data in the relevant literature. Using computer simulation, we evaluated various screening policies to study the impact of mammography screening for age-based subpopulations in Canada. We also performed sensitivity analysis to examine the impact of certain parameters on number of deaths and total costs. The analysis comparing screening policies reveals that a policy in which women belonging to the 40-49 age group are not screened, whereas those belonging to the 50-59 and 60-69 age groups are screened once every 5 years, outperforms others with respect to cost per life saved. Our analysis also indicates that increasing the screening frequencies for the 50-59 and 60-69 age groups decrease mortality, and that the average number of deaths generally decreases with an increase in screening frequency. We found that screening annually for all age groups is associated with the highest costs per life saved. Our analysis thus reveals that cost per life saved increases with an increase in screening frequency. Copyright © 2015 Elsevier Ltd. All rights reserved.

Automation in high-content flow cytometry screening.

Science.gov (United States)

Naumann, U; Wand, M P

2009-09-01

High-content flow cytometric screening (FC-HCS) is a 21st Century technology that combines robotic fluid handling, flow cytometric instrumentation, and bioinformatics software, so that relatively large numbers of flow cytometric samples can be processed and analysed in a short period of time. We revisit a recent application of FC-HCS to the problem of cellular signature definition for acute graft-versus-host-disease. Our focus is on automation of the data processing steps using recent advances in statistical methodology. We demonstrate that effective results, on par with those obtained via manual processing, can be achieved using our automatic techniques. Such automation of FC-HCS has the potential to drastically improve diagnosis and biomarker identification.

A comparison of three approaches to compute the effective Reynolds number of the implicit large-eddy simulations

Energy Technology Data Exchange (ETDEWEB)

Zhou, Ye [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Thornber, Ben [The Univ. of Sydney, Sydney, NSW (Australia)

2016-04-12

Here, the implicit large-eddy simulation (ILES) has been utilized as an effective approach for calculating many complex flows at high Reynolds number flows. Richtmyer–Meshkov instability (RMI) induced flow can be viewed as a homogeneous decaying turbulence (HDT) after the passage of the shock. In this article, a critical evaluation of three methods for estimating the effective Reynolds number and the effective kinematic viscosity is undertaken utilizing high-resolution ILES data. Effective Reynolds numbers based on the vorticity and dissipation rate, or the integral and inner-viscous length scales, are found to be the most self-consistent when compared to the expected phenomenology and wind tunnel experiments.

Screening for triterpenoid saponins in plants using hyphenated analytical platforms

DEFF Research Database (Denmark)

Khakimov, Bekzod; Tseng, Li Hong; Godejohann, Markus

2016-01-01

of saponin profiles from intact plant extracts as well as saponin aglycone profiles from hydrolysed samples. Continuously measured 1D proton NMR data during LC separation along with mass spectrometry data revealed significant differences, including contents of saponins, types of aglycones and numbers......Recently the number of studies investigating triterpenoid saponins has drastically increased due to their diverse and potentially attractive biological activities. Currently the literature contains chemical structures of few hundreds of triterpenoid saponins of plant and animal origin. Triterpenoid...... saponins consist of a triterpene aglycone with one or more sugar moieties attached to it. However, due to similar physico-chemical properties, isolation and identification of a large diversity of triterpenoid saponins remain challenging. This study demonstrates a methodology to screen saponins using...

Screening for infectious diseases of asylum seekers upon arrival: the necessity of the moral principle of reciprocity.

Science.gov (United States)

Beeres, Dorien T; Cornish, Darren; Vonk, Machiel; Ravensbergen, Sofanne J; Maeckelberghe, Els L M; Boele Van Hensbroek, Pieter; Stienstra, Ymkje

2018-03-02

With a large number of forcibly displaced people seeking safety, the EU is facing a challenge in maintaining solidarity. Europe has seen millions of asylum seekers crossing European borders, the largest number of asylum seekers since the second world war. Endemic diseases and often failing health systems in their countries of origin, and arduous conditions during transit, raise questions around how to meet the health needs of this vulnerable population on arrival in terms of screening, vaccination, and access to timely and appropriate statutory health services. This paper explores the potential role of the principle of reciprocity, defined as the disposition 'to return good in proportion to the good we receive, and to make reparations for the harm we have done', as a mid-level principle in infectious disease screening policies. More than half of the European countries implemented screening programmes for newly arrived asylum seekers. Screening may serve to avoid potential infectious disease risks in the receiving countries as well as help identify health needs of asylum seekers. But screening may infringe upon basic rights of those screened, thus creating an ethical dilemma. The use of the principle of reciprocity can contribute to the identification of potential improvements for current screening programmes and emphasizes the importance of certain rights into guidelines for screening. It may create a two way moral obligation, upon asylum seekers to actively participate in the programme, and upon authorities to reciprocate the asylum seekers' participation and the benefits for the control of public health. The authors argue that the reciprocity principle leads to a stronger ethical justification of screening programmes and help achieve a balance between justifiable rights claims of the host population and the asylum seekers. The principle deserves a further and more thorough exploration of its potential use in the field of screening, migration and infectious

Impact of a new national screening policy for Down's syndrome in Denmark

DEFF Research Database (Denmark)

Ekelund, Charlotte K; Jørgensen, Finn Stener; Petersen, Olav Bjørn

2008-01-01

OBJECTIVES: To evaluate the impact of a screening strategy in the first trimester, introduced in Denmark during 2004-6, on the number of infants born with Down's syndrome and the number of chorionic villus samplings and amniocenteses, and to determine detection and false positive rates...... and newborn infants with Down's syndrome diagnosed prenatally and postnatally and number of chorionic villus samplings and amniocenteses carried out. Secondary outcomes measured were number of women screened in 2005 and 2006, screen positive rate, and information on screening in 2005 and 2006 for infants...... with a postnatal diagnosis of Down's syndrome. RESULTS: The number of infants born with Down's syndrome decreased from 55-65 per year during 2000-4 to 31 in 2005 and 32 in 2006. The total number of chorionic villus samplings and amniocenteses carried out decreased from 7524 in 2000 to 3510 in 2006. The detection...

Screening and characterization of Lactobacillus strains producing large amounts of exopolysaccharides

NARCIS (Netherlands)

Geel-Schutten, G.H. van; Flesch, F.; Brink, B. ten; Smith, M.R.; Dijkhuizen, L.

1998-01-01

A total of 182 Lactobacillus strains were screened for production of extracellular polysaccharides (EPS) by a new method: growth in liquid media with high sugar concentrations. Sixty EPS-positive strains were identified; 17 strains produced more than 100 mg/l soluble EPS. Sucrose was an excellent

Prostate and Colon Cancer Screening Messages in Popular Magazines

Science.gov (United States)

Katz, Mira L; Sheridan, Stacey; Pignone, Michael; Lewis, Carmen; Battle, Jamila; Gollop, Claudia; O'Malley, Michael

2004-01-01

OBJECTIVES To 1) compare the number of articles published about prostate, colon, and breast cancer in popular magazines during the past 2 decades, and 2) evaluate the content of in-depth prostate and colon cancer screening articles identified from 1996 to 2001. DESIGN We used a searchable database to identify the number of prostate, colon, and breast cancer articles published in three magazines with the highest circulation from six categories. In addition, we performed a systematic review on the in-depth (≥2 pages) articles on prostate and colon cancer screening that appeared from 1996 through 2001. RESULTS Although the number of magazine articles on prostate and colon cancer published in the 1990s increased compared to the 1980s, the number of articles is approximately one third of breast cancer articles. There were 36 in-depth articles from 1996 to 2001 in which prostate or colon cancer screening were mentioned. Over 90% of the articles recommended screening. However, of those articles, only 76% (25/33; 95% confidence interval [CI], 58% to 89%) cited screening guidelines. The benefits of screening were mentioned in 89% (32/36; 95% CI, 74% to 97%) but the harms were only found in 58% (21/36; 95% CI, 41% to 75%). Only 28% (10/36; 95% CI, 14% to 45%) of the articles provided all the necessary information needed for the reader to make an informed decision. CONCLUSIONS In-depth articles about prostate and colon cancer in popular magazines do not appear as frequently as articles about breast cancer. The available articles on prostate and colon cancer screening often do not provide the information necessary for the reader to make an informed decision about screening. PMID:15242469

Just-in-Time Compound Pooling Increases Primary Screening Capacity without Compromising Screening Quality.

Science.gov (United States)

Elkin, L L; Harden, D G; Saldanha, S; Ferguson, H; Cheney, D L; Pieniazek, S N; Maloney, D P; Zewinski, J; O'Connell, J; Banks, M

2015-06-01

Compound pooling, or multiplexing more than one compound per well during primary high-throughput screening (HTS), is a controversial approach with a long history of limited success. Many issues with this approach likely arise from long-term storage of library plates containing complex mixtures of compounds at high concentrations. Due to the historical difficulties with using multiplexed library plates, primary HTS often uses a one-compound-one-well approach. However, as compound collections grow, innovative strategies are required to increase the capacity of primary screening campaigns. Toward this goal, we have developed a novel compound pooling method that increases screening capacity without compromising data quality. This method circumvents issues related to the long-term storage of complex compound mixtures by using acoustic dispensing to enable "just-in-time" compound pooling directly in the assay well immediately prior to assay. Using this method, we can pool two compounds per well, effectively doubling the capacity of a primary screen. Here, we present data from pilot studies using just-in-time pooling, as well as data from a large >2-million-compound screen using this approach. These data suggest that, for many targets, this method can be used to vastly increase screening capacity without significant reduction in the ability to detect screening hits. © 2015 Society for Laboratory Automation and Screening.

The relative and absolute speed of radiographic screen - film systems

International Nuclear Information System (INIS)

Lee, In Ja; Huh, Joon

1993-01-01

Recently, a large number of new screen-film systems have become available for use in diagnostic radiology. These new screens are made of materials generally known as rare - earth phosphors which have high x-ray absorption and high x-ray to light conversion efficiency compared to calcium tungstate phosphors. The major advantage of these new systems is reduction of patient exposure due to their high speed or high sensitivity. However, a system with excessively high speed can result in a significant degradation of radiographic image quality. Therefore, the speed is important parameters for users of these system. Our aim of in this was to determine accurately and precisely the absolute speed and relative speeds of both new and conventional screen - film system. We determined the absolute speed in condition of BRH phantom beam quality and the relative speed were measured by a split - screen technique in condition of BRH and ANSI phantom beam quality. The absolute and the relative speed were determined for 8 kinds of screen - 4 kinds of film in regular system and 7 kinds pf screen - 7 kinds of film in ortho system. In this study we could know the New Rx, T - MAT G has the highest film speed, also know Green system's standard deviation of relative speed larger than blue system. It was realized that there were no relationship between the absolute speed and the blue system. It was realized that there were no relationship between the absolute speed and the relative speed in ortho or regular system

Screening of newborns for congenital hypothyroidism. Guidance for developing programmes

International Nuclear Information System (INIS)

2005-12-01

Congenital hypothyroidism is a condition that, if left untreated, can cause lifelong human suffering as a result of severe mental retardation and deficiency of growth. With the involvement of the IAEA, screening programmes to detect congenital hypothyroidism in newborn infants have been introduced successfully in a large number of countries. The cornerstone of these programmes is accurate and reliable screening methods involving isotope techniques and simple medical treatment. The suffering - and heavy social and economic burden - caused by congenital hypothyroidism prompted many countries to institute a formalized screening programme directed at newborns, just as a vaccination programme has become an integral part of child health care. In many other countries however, this type of formalized service has not yet been established. For these countries, the implementation of a neonatal screening programme will bring about a considerable improvement in child health care. It is hoped that the guidance in this publication will be especially useful to the signatories of the United Nations Convention on the Rights of the Child. Several factors that prevail in a country - the climate, political environment, economic development, level of health care and the transportation system - have an influence on the overall operational systems, design and implementation of a screening programme. As such, the design of such a programme will differ greatly from country to country. Nevertheless, neonatal screening programmes have many elements in common. This book draws on the IAEA's experience in this area over more than a decade, and on the results of a regional technical cooperation programme on neonatal screening for congenital hypothyroidism in East Asia (IAEA Project RAS6032). This publication provides guidance aimed specifically at implementing and sustaining programmes for the screening of newborn infants

People's willingness to accept overdetection in cancer screening: population survey.

Science.gov (United States)

Van den Bruel, Ann; Jones, Caroline; Yang, Yaling; Oke, Jason; Hewitson, Paul

2015-03-03

To describe the level of overdetection people would find acceptable in screening for breast, prostate, and bowel cancer and whether acceptability is influenced by the magnitude of the benefit from screening and the cancer specific harms from overdetection. Online survey. Women were presented with scenarios on breast and bowel cancer, men with scenarios on prostate and bowel cancer. For each particular cancer, we presented epidemiological information and described the treatment and its consequences. Secondly, we presented two different scenarios of benefit: one indicating a 10% reduction in cancer specific mortality and the second indicating a 50% reduction. Online survey of the population in the United Kingdom. Respondents were part of an existing panel of people who volunteer for online research and were invited by email or online marketing. We recruited 1000 respondents, representative for age and sex for the UK population. Number of cases of overdetection people were willing to accept, ranging from 0-1000 (complete screened population) for each cancer modality and each scenario of benefit. There was large variability between respondents in the level of overdetection they would find acceptable, with medians ranging from 113 to 313 cases of overdetection per 1000 people screened. Across all scenarios, 4-7% of respondents indicated they would accept no overdetection at all compared with 7-14% who thought that it would be acceptable for the entire screened population to be overdetected. Acceptability in screening for bowel cancer was significantly lower than for breast and prostate cancer. People aged 50 or over accepted significantly less overdetection, whereas people with higher education levels accepted more; 29% of respondents had heard of overdetection before. Acceptability of overdetection in cancer screening is variable. Invitations for screening should include clear information on the likelihood and consequences of overdetection to allow people to make an

High-Throughput Genetic Screens Identify a Large and Diverse Collection of New Sporulation Genes in Bacillus subtilis.

Science.gov (United States)

Meeske, Alexander J; Rodrigues, Christopher D A; Brady, Jacqueline; Lim, Hoong Chuin; Bernhardt, Thomas G; Rudner, David Z

2016-01-01

The differentiation of the bacterium Bacillus subtilis into a dormant spore is among the most well-characterized developmental pathways in biology. Classical genetic screens performed over the past half century identified scores of factors involved in every step of this morphological process. More recently, transcriptional profiling uncovered additional sporulation-induced genes required for successful spore development. Here, we used transposon-sequencing (Tn-seq) to assess whether there were any sporulation genes left to be discovered. Our screen identified 133 out of the 148 genes with known sporulation defects. Surprisingly, we discovered 24 additional genes that had not been previously implicated in spore formation. To investigate their functions, we used fluorescence microscopy to survey early, middle, and late stages of differentiation of null mutants from the B. subtilis ordered knockout collection. This analysis identified mutants that are delayed in the initiation of sporulation, defective in membrane remodeling, and impaired in spore maturation. Several mutants had novel sporulation phenotypes. We performed in-depth characterization of two new factors that participate in cell-cell signaling pathways during sporulation. One (SpoIIT) functions in the activation of σE in the mother cell; the other (SpoIIIL) is required for σG activity in the forespore. Our analysis also revealed that as many as 36 sporulation-induced genes with no previously reported mutant phenotypes are required for timely spore maturation. Finally, we discovered a large set of transposon insertions that trigger premature initiation of sporulation. Our results highlight the power of Tn-seq for the discovery of new genes and novel pathways in sporulation and, combined with the recently completed null mutant collection, open the door for similar screens in other, less well-characterized processes.

High-Throughput Genetic Screens Identify a Large and Diverse Collection of New Sporulation Genes in Bacillus subtilis

Science.gov (United States)

Brady, Jacqueline; Lim, Hoong Chuin; Bernhardt, Thomas G.; Rudner, David Z.

2016-01-01

The differentiation of the bacterium Bacillus subtilis into a dormant spore is among the most well-characterized developmental pathways in biology. Classical genetic screens performed over the past half century identified scores of factors involved in every step of this morphological process. More recently, transcriptional profiling uncovered additional sporulation-induced genes required for successful spore development. Here, we used transposon-sequencing (Tn-seq) to assess whether there were any sporulation genes left to be discovered. Our screen identified 133 out of the 148 genes with known sporulation defects. Surprisingly, we discovered 24 additional genes that had not been previously implicated in spore formation. To investigate their functions, we used fluorescence microscopy to survey early, middle, and late stages of differentiation of null mutants from the B. subtilis ordered knockout collection. This analysis identified mutants that are delayed in the initiation of sporulation, defective in membrane remodeling, and impaired in spore maturation. Several mutants had novel sporulation phenotypes. We performed in-depth characterization of two new factors that participate in cell–cell signaling pathways during sporulation. One (SpoIIT) functions in the activation of σE in the mother cell; the other (SpoIIIL) is required for σG activity in the forespore. Our analysis also revealed that as many as 36 sporulation-induced genes with no previously reported mutant phenotypes are required for timely spore maturation. Finally, we discovered a large set of transposon insertions that trigger premature initiation of sporulation. Our results highlight the power of Tn-seq for the discovery of new genes and novel pathways in sporulation and, combined with the recently completed null mutant collection, open the door for similar screens in other, less well-characterized processes. PMID:26735940

ACOG committee opinion. Number 318, October 2005. Screening for Tay-Sachs disease.

Science.gov (United States)

2005-10-01

Tay-Sachs disease (TSD) is a severe progressive neurologic disease that causes death in early childhood. Carrier screening, should be offered before pregnancy to individuals and couples at high-risk, including those of Ashkenazi Jewish, French-Canadian, or Cajun descent and those with a family history consistent with TSD. If both partners are determined to be carriers of TSD, genetic counseling and prenatal diagnosis should be offered.

SVA retrotransposon insertion-associated deletion represents a novel mutational mechanism underlying large genomic copy number changes with non-recurrent breakpoints

Science.gov (United States)

2014-01-01

Background Genomic disorders are caused by copy number changes that may exhibit recurrent breakpoints processed by nonallelic homologous recombination. However, region-specific disease-associated copy number changes have also been observed which exhibit non-recurrent breakpoints. The mechanisms underlying these non-recurrent copy number changes have not yet been fully elucidated. Results We analyze large NF1 deletions with non-recurrent breakpoints as a model to investigate the full spectrum of causative mechanisms, and observe that they are mediated by various DNA double strand break repair mechanisms, as well as aberrant replication. Further, two of the 17 NF1 deletions with non-recurrent breakpoints, identified in unrelated patients, occur in association with the concomitant insertion of SINE/variable number of tandem repeats/Alu (SVA) retrotransposons at the deletion breakpoints. The respective breakpoints are refractory to analysis by standard breakpoint-spanning PCRs and are only identified by means of optimized PCR protocols designed to amplify across GC-rich sequences. The SVA elements are integrated within SUZ12P intron 8 in both patients, and were mediated by target-primed reverse transcription of SVA mRNA intermediates derived from retrotranspositionally active source elements. Both SVA insertions occurred during early postzygotic development and are uniquely associated with large deletions of 1 Mb and 867 kb, respectively, at the insertion sites. Conclusions Since active SVA elements are abundant in the human genome and the retrotranspositional activity of many SVA source elements is high, SVA insertion-associated large genomic deletions encompassing many hundreds of kilobases could constitute a novel and as yet under-appreciated mechanism underlying large-scale copy number changes in the human genome. PMID:24958239

Newborn screening for galactosaemia.

Science.gov (United States)

Lak, Rohollah; Yazdizadeh, Bahareh; Davari, Majid; Nouhi, Mojtaba; Kelishadi, Roya

2017-12-23

Classical galactosaemia is an autosomal recessive inborn error of metabolism caused by a deficiency of the enzyme galactose-1-phosphate uridyltransferase. This is a rare and potentially lethal condition that classically presents in the first week of life once milk feeds have commenced. Affected babies may present with any or all of the following: cataracts; fulminant liver failure; prolonged jaundice; or Escherichia coli sepsis. Once the diagnosis is suspected, feeds containing galactose must be stopped immediately and replaced with a soya-based formula. The majority of babies will recover, however a number will not survive. There are long-term complications of galactosaemia, despite treatment, including learning disabilities and female infertility. It has been postulated that galactosaemia could be detected on newborn screening and this would prevent the immediate severe liver dysfunction and sepsis. To assess whether there is evidence that newborn screening for galactosaemia prevents or reduces mortality and morbidity and improves clinical outcomes in affected neonates and the quality of life in older children. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from electronic database searches, handsearches of relevant journals and conference abstract books. We also searched online trials registries and the reference lists of relevant articles and reviews.Date of the most recent search of Cochrane Cystic Fibrosis Group's Trials Register: 18 December 2017.Date of the most recent search of additional resources: 11 October 2017. Randomised controlled studies and controlled clinical studies, published or unpublished comparing the use of any newborn screening test to diagnose infants with galactosaemia and presenting a comparison between a screened population versus a non-screened population. No studies of newborn screening for galactosaemia were found. No studies were identified for inclusion in the

Newborn screening of inherited metabolic disorders by tandem mass spectrometry: past, present and future

Directory of Open Access Journals (Sweden)

G. Scaturro

2013-04-01

Full Text Available Inborn errors of metabolism are inherited biochemical disorders caused by lack of a functional enzyme, transmembrane transporter, or similar protein, which then results in blockage of the corresponding metabolic pathway. Taken individually, inborn errors of metabolism are rare. However, as a group these diseases are relatively frequent and they may account for most of neonatal mortality and need of health resources. The detection of genetic metabolic disorders should occur in a pre-symptomatic phase. Recently, the introduction of the tandem mass spectrometric methods for metabolite analysis has changed our ability to detect intermediates of metabolism in smaller samples and provides the means to detect a large number of metabolic disorders in a single analytical run. Screening panels now include a large number of disorders that may not meet all the criteria that have been used as a reference for years. The rationale behind inclusion or exclusion of a respective disorder is difficult to understand in most cases and it may impose an ethical dilemma. The current organization is an important tool of secondary preventive medicine, essential for children’s healthcare, but the strong inhomogeneity of the regional models of screening applied today create in the Italian neonatal population macroscopic differences with regards to healthcare, which is in effect mainly diversified by the newborn’s place of birth, in possible violation of the universal criterion of the equality of all citizens. Carefully weighed arguments are urgently needed since patient organizations, opinion leaders and politicians are pressing to proceed with expansion of neonatal population screening.

The challenge for genetic epidemiologists: how to analyze large numbers of SNPs in relation to complex diseases

NARCIS (Netherlands)

Heidema, A.G.; Boer, J.M.A.; Nagelkerke, N.; Mariman, E.C.M.; A, van der D.L.; Feskens, E.J.M.

2006-01-01

Genetic epidemiologists have taken the challenge to identify genetic polymorphisms involved in the development of diseases. Many have collected data on large numbers of genetic markers but are not familiar with available methods to assess their association with complex diseases. Statistical methods

The influence of the negative-positive ratio and screening database size on the performance of machine learning-based virtual screening.

Science.gov (United States)

Kurczab, Rafał; Bojarski, Andrzej J

2017-01-01

The machine learning-based virtual screening of molecular databases is a commonly used approach to identify hits. However, many aspects associated with training predictive models can influence the final performance and, consequently, the number of hits found. Thus, we performed a systematic study of the simultaneous influence of the proportion of negatives to positives in the testing set, the size of screening databases and the type of molecular representations on the effectiveness of classification. The results obtained for eight protein targets, five machine learning algorithms (SMO, Naïve Bayes, Ibk, J48 and Random Forest), two types of molecular fingerprints (MACCS and CDK FP) and eight screening databases with different numbers of molecules confirmed our previous findings that increases in the ratio of negative to positive training instances greatly influenced most of the investigated parameters of the ML methods in simulated virtual screening experiments. However, the performance of screening was shown to also be highly dependent on the molecular library dimension. Generally, with the increasing size of the screened database, the optimal training ratio also increased, and this ratio can be rationalized using the proposed cost-effectiveness threshold approach. To increase the performance of machine learning-based virtual screening, the training set should be constructed in a way that considers the size of the screening database.

THE DEVELOPMENT OF SCREEN TRANSLATION

OpenAIRE

Sang Ayu Isnu Maharani

2014-01-01

Screen translations involve oral translation known as dubbing and revoicing. Re-voicing consists of lip-sync dubbing, free commentary, narration and voice over. The written version is called subtitle. Dubbing and subtitling are two preferred mode used in the screen translation even though various numbers of current options are available nowadays. Dubbing commenced to be used in larger countries in Europe meanwhile smaller countries apply subtitling because it is more...

Introducing Bayesian thinking to high-throughput screening for false-negative rate estimation.

Science.gov (United States)

Wei, Xin; Gao, Lin; Zhang, Xiaolei; Qian, Hong; Rowan, Karen; Mark, David; Peng, Zhengwei; Huang, Kuo-Sen

2013-10-01

High-throughput screening (HTS) has been widely used to identify active compounds (hits) that bind to biological targets. Because of cost concerns, the comprehensive screening of millions of compounds is typically conducted without replication. Real hits that fail to exhibit measurable activity in the primary screen due to random experimental errors will be lost as false-negatives. Conceivably, the projected false-negative rate is a parameter that reflects screening quality. Furthermore, it can be used to guide the selection of optimal numbers of compounds for hit confirmation. Therefore, a method that predicts false-negative rates from the primary screening data is extremely valuable. In this article, we describe the implementation of a pilot screen on a representative fraction (1%) of the screening library in order to obtain information about assay variability as well as a preliminary hit activity distribution profile. Using this training data set, we then developed an algorithm based on Bayesian logic and Monte Carlo simulation to estimate the number of true active compounds and potential missed hits from the full library screen. We have applied this strategy to five screening projects. The results demonstrate that this method produces useful predictions on the numbers of false negatives.

Quantification of bacteria on abiotic surfaces by laser scanning cytometry: An automated approach to screen the antifouling properties of new surface coatings

DEFF Research Database (Denmark)

Regina, Viduthalai R.; Poulsen, Morten; Søhoel, Helmer

2012-01-01

Bacterial biofilms are a persistent source of contamination, and much effort invested in developing antifouling surfaces or coatings. A bottle-neck in developing such coatings is often the time-consuming task of screening and evaluating a large number of surface materials. An automated high...

Enhancing Reproducibility in Cancer Drug Screening: How Do We Move Forward?

DEFF Research Database (Denmark)

Shi, Leming; Haibe-Kains, Benjamin; Birkbak, Nicolai Juul

2014-01-01

Large-scale pharmacogenomic high-throughput screening (HTS) studies hold great potential for generating robust genomic predictors of drug response. Two recent large-scale HTS studies have reported results of such screens, revealing several known and novel drug sensitivities and biomarkers...

Benefit-risk evaluation of mammographic mass screening

International Nuclear Information System (INIS)

Sato, Nobuo; Ogura, Toshihiro

1990-01-01

This study evaluated the benefit-risk balance of mammography in mass screening by using survival rates from 3000 breast cancer patients at the Japanese Foundation for Cancer Research Institute Hospital. Because the number of participants in mammographic mass screening was small, asymptomatic patients with pathologically proven early breast cancer were categorized as the screenee group. Symptomatic patients were categorized as the patient group. Survival rates were compared in both the screenee and the patient groups. Based on the difference in areas of survival curves between screenees and patients, the ratio of person-year gain (PYG) to person-year lost (PYL) was obtained. The ratio of PYG to PYL was multiplied by the detection rate resulting from a particular screening program to obtain the benefit/risk ratio. The detection rate of nonpalpable breast cancer was 15 times higher in the screenee group than the patient group. Breast cancer was detected in 7 (0.85%) of 824 patients in the screenee group. Even when mammographic mass screening was started at the age of 30, the benefit of mammography was far superior to the risk. The number of participants in mass screening stratified by age may be required for the conclusion of the benefit-risk balance of mammography in mass screening. (N.K.)

Accurate, high-throughput typing of copy number variation using paralogue ratios from dispersed repeats.

Science.gov (United States)

Armour, John A L; Palla, Raquel; Zeeuwen, Patrick L J M; den Heijer, Martin; Schalkwijk, Joost; Hollox, Edward J

2007-01-01

Recent work has demonstrated an unexpected prevalence of copy number variation in the human genome, and has highlighted the part this variation may play in predisposition to common phenotypes. Some important genes vary in number over a high range (e.g. DEFB4, which commonly varies between two and seven copies), and have posed formidable technical challenges for accurate copy number typing, so that there are no simple, cheap, high-throughput approaches suitable for large-scale screening. We have developed a simple comparative PCR method based on dispersed repeat sequences, using a single pair of precisely designed primers to amplify products simultaneously from both test and reference loci, which are subsequently distinguished and quantified via internal sequence differences. We have validated the method for the measurement of copy number at DEFB4 by comparison of results from >800 DNA samples with copy number measurements by MAPH/REDVR, MLPA and array-CGH. The new Paralogue Ratio Test (PRT) method can require as little as 10 ng genomic DNA, appears to be comparable in accuracy to the other methods, and for the first time provides a rapid, simple and inexpensive method for copy number analysis, suitable for application to typing thousands of samples in large case-control association studies.

Infant outcomes among women with Zika virus infection during pregnancy: results of a large prenatal Zika screening program.

Science.gov (United States)

Adhikari, Emily H; Nelson, David B; Johnson, Kathryn A; Jacobs, Sara; Rogers, Vanessa L; Roberts, Scott W; Sexton, Taylor; McIntire, Donald D; Casey, Brian M

2017-03-01

Zika virus infection during pregnancy is a known cause of congenital microcephaly and other neurologic morbidities. We present the results of a large-scale prenatal screening program in place at a single-center health care system since March 14, 2016. Our aims were to report the baseline prevalence of travel-associated Zika infection in our pregnant population, determine travel characteristics of women with evidence of Zika infection, and evaluate maternal and neonatal outcomes compared to women without evidence of Zika infection. This is a prospective, observational study of prenatal Zika virus screening in our health care system. We screened all pregnant women for recent travel to a Zika-affected area, and the serum was tested for those considered at risk for infection. We compared maternal demographic and travel characteristics and perinatal outcomes among women with positive and negative Zika virus tests during pregnancy. Comprehensive neurologic evaluation was performed on all infants delivered of women with evidence of possible Zika virus infection during pregnancy. Head circumference percentiles by gestational age were compared for infants delivered of women with positive and negative Zika virus test results. From March 14 through Oct. 1, 2016, a total of 14,161 pregnant women were screened for travel to a Zika-affected country. A total of 610 (4.3%) women reported travel, and test results were available in 547. Of these, evidence of possible Zika virus infection was found in 29 (5.3%). In our population, the prevalence of asymptomatic or symptomatic Zika virus infection among pregnant women was 2/1000. Women with evidence of Zika virus infection were more likely to have traveled from Central or South America (97% vs 12%, P Zika virus infection. Additionally, there was no difference in mean head circumference of infants born to women with positive vs negative Zika virus testing. No microcephalic infants born to women with Zika infection were identified

Evaluation of Origin Ensemble algorithm for image reconstruction for pixelated solid-state detectors with large number of channels

Science.gov (United States)

Kolstein, M.; De Lorenzo, G.; Mikhaylova, E.; Chmeissani, M.; Ariño, G.; Calderón, Y.; Ozsahin, I.; Uzun, D.

2013-04-01

The Voxel Imaging PET (VIP) Pathfinder project intends to show the advantages of using pixelated solid-state technology for nuclear medicine applications. It proposes designs for Positron Emission Tomography (PET), Positron Emission Mammography (PEM) and Compton gamma camera detectors with a large number of signal channels (of the order of 106). For PET scanners, conventional algorithms like Filtered Back-Projection (FBP) and Ordered Subset Expectation Maximization (OSEM) are straightforward to use and give good results. However, FBP presents difficulties for detectors with limited angular coverage like PEM and Compton gamma cameras, whereas OSEM has an impractically large time and memory consumption for a Compton gamma camera with a large number of channels. In this article, the Origin Ensemble (OE) algorithm is evaluated as an alternative algorithm for image reconstruction. Monte Carlo simulations of the PET design are used to compare the performance of OE, FBP and OSEM in terms of the bias, variance and average mean squared error (MSE) image quality metrics. For the PEM and Compton camera designs, results obtained with OE are presented.

Noise Reduction in High-Throughput Gene Perturbation Screens

Science.gov (United States)

Motivation: Accurate interpretation of perturbation screens is essential for a successful functional investigation. However, the screened phenotypes are often distorted by noise, and their analysis requires specialized statistical analysis tools. The number and scope of statistical methods available...

Screening and large-scale expression of membrane proteins in mammalian cells for structural studies

OpenAIRE

Goehring, April; Lee, Chia-Hsueh; Wang, Kevin H.; Michel, Jennifer Carlisle; Claxton, Derek P.; Baconguis, Isabelle; Althoff, Thorsten; Fischer, Suzanne; Garcia, K. Christopher; Gouaux, Eric

2014-01-01

Structural, biochemical and biophysical studies of eukaryotic membrane proteins are often hampered by difficulties in over-expression of the candidate molecule. Baculovirus transduction of mammalian cells (BacMam), although a powerful method to heterologously express membrane proteins, can be cumbersome for screening and expression of multiple constructs. We therefore developed plasmid Eric Gouaux (pEG) BacMam, a vector optimized for use in screening assays, as well as for efficient productio...

Phases of a stack of membranes in a large number of dimensions of configuration space

Science.gov (United States)

Borelli, M. E.; Kleinert, H.

2001-05-01

The phase diagram of a stack of tensionless membranes with nonlinear curvature energy and vertical harmonic interaction is calculated exactly in a large number of dimensions of configuration space. At low temperatures, the system forms a lamellar phase with spontaneously broken translational symmetry in the vertical direction. At a critical temperature, the stack disorders vertically in a meltinglike transition. The critical temperature is determined as a function of the interlayer separation l.

Hierarchical screening for multiple mental disorders.

Science.gov (United States)

Batterham, Philip J; Calear, Alison L; Sunderland, Matthew; Carragher, Natacha; Christensen, Helen; Mackinnon, Andrew J

2013-10-01

There is a need for brief, accurate screening when assessing multiple mental disorders. Two-stage hierarchical screening, consisting of brief pre-screening followed by a battery of disorder-specific scales for those who meet diagnostic criteria, may increase the efficiency of screening without sacrificing precision. This study tested whether more efficient screening could be gained using two-stage hierarchical screening than by administering multiple separate tests. Two Australian adult samples (N=1990) with high rates of psychopathology were recruited using Facebook advertising to examine four methods of hierarchical screening for four mental disorders: major depressive disorder, generalised anxiety disorder, panic disorder and social phobia. Using K6 scores to determine whether full screening was required did not increase screening efficiency. However, pre-screening based on two decision tree approaches or item gating led to considerable reductions in the mean number of items presented per disorder screened, with estimated item reductions of up to 54%. The sensitivity of these hierarchical methods approached 100% relative to the full screening battery. Further testing of the hierarchical screening approach based on clinical criteria and in other samples is warranted. The results demonstrate that a two-phase hierarchical approach to screening multiple mental disorders leads to considerable increases efficiency gains without reducing accuracy. Screening programs should take advantage of prescreeners based on gating items or decision trees to reduce the burden on respondents. © 2013 Elsevier B.V. All rights reserved.

Low field pulsed NMR- a mass screening tool in agricultural research

International Nuclear Information System (INIS)

Tiwari, P.N.

1994-01-01

One of the main requirements in agricultural research is to analyse large number of samples for their one or more chemical constituents and physical properties. In plant breeding programmes and germplasm evaluation, it is necessary that the analysis is fast as many samples are to be analysed. Pulsed nuclear magnetic resonance (NMR) is a potential tool for developing rapid and nondestructive method of analysis. Various applications of low resolution pulsed NMR in agricultural research, which are generally used as screening method are briefly described. 25 refs., 2 figs., 2 tabs

Uncertainty of mass discharge estimation from contaminated sites at screening level

DEFF Research Database (Denmark)

Thomsen, Nanna Isbak; Troldborg, M.; McKnight, Ursula S.

Contaminated sites threaten groundwater resources worldwide. The number of contaminated sites is large and there are too few economic resources available to ensure a thorough investigation and remediation of them all. Risk assessment must already be done at a screening level in order to ensure...... consider possible source and hydrogeological descriptions, where each model is believed to be a realistic representation of the given site, based on the current level of information. Parameter uncertainty is quantified using Monte Carlo simulations. For each conceptual model we calculate a transient mass...

Large Scale Gaussian Processes for Atmospheric Parameter Retrieval and Cloud Screening

Science.gov (United States)

Camps-Valls, G.; Gomez-Chova, L.; Mateo, G.; Laparra, V.; Perez-Suay, A.; Munoz-Mari, J.

2017-12-01

Current Earth-observation (EO) applications for image classification have to deal with an unprecedented big amount of heterogeneous and complex data sources. Spatio-temporally explicit classification methods are a requirement in a variety of Earth system data processing applications. Upcoming missions such as the super-spectral Copernicus Sentinels EnMAP and FLEX will soon provide unprecedented data streams. Very high resolution (VHR) sensors like Worldview-3 also pose big challenges to data processing. The challenge is not only attached to optical sensors but also to infrared sounders and radar images which increased in spectral, spatial and temporal resolution. Besides, we should not forget the availability of the extremely large remote sensing data archives already collected by several past missions, such ENVISAT, Cosmo-SkyMED, Landsat, SPOT, or Seviri/MSG. These large-scale data problems require enhanced processing techniques that should be accurate, robust and fast. Standard parameter retrieval and classification algorithms cannot cope with this new scenario efficiently. In this work, we review the field of large scale kernel methods for both atmospheric parameter retrieval and cloud detection using infrared sounding IASI data and optical Seviri/MSG imagery. We propose novel Gaussian Processes (GPs) to train problems with millions of instances and high number of input features. Algorithms can cope with non-linearities efficiently, accommodate multi-output problems, and provide confidence intervals for the predictions. Several strategies to speed up algorithms are devised: random Fourier features and variational approaches for cloud classification using IASI data and Seviri/MSG, and engineered randomized kernel functions and emulation in temperature, moisture and ozone atmospheric profile retrieval from IASI as a proxy to the upcoming MTG-IRS sensor. Excellent compromise between accuracy and scalability are obtained in all applications.

Virtual screening of compound libraries.

Science.gov (United States)

Cerqueira, Nuno M F S A; Sousa, Sérgio F; Fernandes, Pedro A; Ramos, Maria João

2009-01-01

During the last decade, Virtual Screening (VS) has definitively established itself as an important part of the drug discovery and development process. VS involves the selection of likely drug candidates from large libraries of chemical structures by using computational methodologies, but the generic definition of VS encompasses many different methodologies. This chapter provides an introduction to the field by reviewing a variety of important aspects, including the different types of virtual screening methods, and the several steps required for a successful virtual screening campaign within a state-of-the-art approach, from target selection to postfilter application. This analysis is further complemented with a small collection important VS success stories.

Virtual screening applications: a study of ligand-based methods and different structure representations in four different scenarios.

Science.gov (United States)

Hristozov, Dimitar P; Oprea, Tudor I; Gasteiger, Johann

2007-01-01

Four different ligand-based virtual screening scenarios are studied: (1) prioritizing compounds for subsequent high-throughput screening (HTS); (2) selecting a predefined (small) number of potentially active compounds from a large chemical database; (3) assessing the probability that a given structure will exhibit a given activity; (4) selecting the most active structure(s) for a biological assay. Each of the four scenarios is exemplified by performing retrospective ligand-based virtual screening for eight different biological targets using two large databases--MDDR and WOMBAT. A comparison between the chemical spaces covered by these two databases is presented. The performance of two techniques for ligand--based virtual screening--similarity search with subsequent data fusion (SSDF) and novelty detection with Self-Organizing Maps (ndSOM) is investigated. Three different structure representations--2,048-dimensional Daylight fingerprints, topological autocorrelation weighted by atomic physicochemical properties (sigma electronegativity, polarizability, partial charge, and identity) and radial distribution functions weighted by the same atomic physicochemical properties--are compared. Both methods were found applicable in scenario one. The similarity search was found to perform slightly better in scenario two while the SOM novelty detection is preferred in scenario three. No method/descriptor combination achieved significant success in scenario four.

GeauxDock: Accelerating Structure-Based Virtual Screening with Heterogeneous Computing

Science.gov (United States)

Fang, Ye; Ding, Yun; Feinstein, Wei P.; Koppelman, David M.; Moreno, Juana; Jarrell, Mark; Ramanujam, J.; Brylinski, Michal

2016-01-01

Computational modeling of drug binding to proteins is an integral component of direct drug design. Particularly, structure-based virtual screening is often used to perform large-scale modeling of putative associations between small organic molecules and their pharmacologically relevant protein targets. Because of a large number of drug candidates to be evaluated, an accurate and fast docking engine is a critical element of virtual screening. Consequently, highly optimized docking codes are of paramount importance for the effectiveness of virtual screening methods. In this communication, we describe the implementation, tuning and performance characteristics of GeauxDock, a recently developed molecular docking program. GeauxDock is built upon the Monte Carlo algorithm and features a novel scoring function combining physics-based energy terms with statistical and knowledge-based potentials. Developed specifically for heterogeneous computing platforms, the current version of GeauxDock can be deployed on modern, multi-core Central Processing Units (CPUs) as well as massively parallel accelerators, Intel Xeon Phi and NVIDIA Graphics Processing Unit (GPU). First, we carried out a thorough performance tuning of the high-level framework and the docking kernel to produce a fast serial code, which was then ported to shared-memory multi-core CPUs yielding a near-ideal scaling. Further, using Xeon Phi gives 1.9× performance improvement over a dual 10-core Xeon CPU, whereas the best GPU accelerator, GeForce GTX 980, achieves a speedup as high as 3.5×. On that account, GeauxDock can take advantage of modern heterogeneous architectures to considerably accelerate structure-based virtual screening applications. GeauxDock is open-sourced and publicly available at www.brylinski.org/geauxdock and https://figshare.com/articles/geauxdock_tar_gz/3205249. PMID:27420300

GeauxDock: Accelerating Structure-Based Virtual Screening with Heterogeneous Computing.

Directory of Open Access Journals (Sweden)

Ye Fang

Full Text Available Computational modeling of drug binding to proteins is an integral component of direct drug design. Particularly, structure-based virtual screening is often used to perform large-scale modeling of putative associations between small organic molecules and their pharmacologically relevant protein targets. Because of a large number of drug candidates to be evaluated, an accurate and fast docking engine is a critical element of virtual screening. Consequently, highly optimized docking codes are of paramount importance for the effectiveness of virtual screening methods. In this communication, we describe the implementation, tuning and performance characteristics of GeauxDock, a recently developed molecular docking program. GeauxDock is built upon the Monte Carlo algorithm and features a novel scoring function combining physics-based energy terms with statistical and knowledge-based potentials. Developed specifically for heterogeneous computing platforms, the current version of GeauxDock can be deployed on modern, multi-core Central Processing Units (CPUs as well as massively parallel accelerators, Intel Xeon Phi and NVIDIA Graphics Processing Unit (GPU. First, we carried out a thorough performance tuning of the high-level framework and the docking kernel to produce a fast serial code, which was then ported to shared-memory multi-core CPUs yielding a near-ideal scaling. Further, using Xeon Phi gives 1.9× performance improvement over a dual 10-core Xeon CPU, whereas the best GPU accelerator, GeForce GTX 980, achieves a speedup as high as 3.5×. On that account, GeauxDock can take advantage of modern heterogeneous architectures to considerably accelerate structure-based virtual screening applications. GeauxDock is open-sourced and publicly available at www.brylinski.org/geauxdock and https://figshare.com/articles/geauxdock_tar_gz/3205249.

Obtaining the electrostatic screening from first principles

International Nuclear Information System (INIS)

Shaviv, N.J.; Shaviv, G.

2003-01-01

We derive the electrostatic screening effect from first principles and show the basic properties of the screening process. We in particular show that under the conditions prevailing in the Sun the number of particles in the Debye sphere is of the order of unity. Consequently; fluctuations play a dominant role in the screening process. The fluctuations lead to an effective time dependent potential. Particles with low kinetic energy lose on the average energy to the plasma and vice versa with high energy particles. We derive general conditions on the screening energy and show under what conditions the Salpeter approximation is obtained. The connection between the screening and relaxation processes in the plasma is exposed

Barriers to Mammography among Inadequately Screened Women

Science.gov (United States)

Stoll, Carolyn R. T.; Roberts, Summer; Cheng, Meng-Ru; Crayton, Eloise V.; Jackson, Sherrill; Politi, Mary C.

2015-01-01

Mammography use has increased over the past 20 years, yet more than 30% of women remain inadequately screened. Structural barriers can deter individuals from screening, however, cognitive, emotional, and communication barriers may also prevent mammography use. This study sought to identify the impact of number and type of barriers on mammography…

The predictive power of depression screening procedures for veterans with coronary artery disease

Directory of Open Access Journals (Sweden)

Shankman SA

2012-04-01

Full Text Available Stewart A Shankman1*, Jeffrey Nadelson2*, Sarah Kate McGowan1, Ali A Sovari2, Mladen I Vidovich21Department of Psychiatry and Psychology, University of Illinois, 2Department of Cardiology, Jesse Brown VA Medical Center, Chicago, IL, USA*These authors contributed equally to this workAbstract: Depression leads to a worse outcome for patients with coronary artery disease (CAD. Thus, accurately identifying depression in CAD patients is imperative. In many veterans affairs (VA hospitals, patients are screened for depression once a year using the patient health questionnaire (PHQ-9. Although the PHQ-9 is generally considered a specific and sensitive measure of depression, there is reason to believe that these screening procedures may miss a large number of cases of depression within CAD patients and cardiology patients more generally. The goal of this study was to provide data as to the predictive power of this depression screening procedure by (a comparing the prevalence rate of depression identified by the PHQ-9 to known prevalence rates and (b examining whether patients identified as “depressed” also had conditions that consistently co-occur with depression (eg, post-traumatic stress disorder [PTSD], other medical issues. Participants were 813 consecutive patients who received an angiogram in the cardiac catheterization laboratory at a large VA Medical Center. Prevalence of depression was 6.9% in the overall sample and less than 6% when the sample was restricted to CAD patients with significant stenosis. Depression was significantly associated with PTSD, smoking, and alcohol problems. However, depression was not associated with other medical problems such as diabetes, renal failure, peripheral vascular disease, or anemia. In conclusion, the low prevalence rate of depression and lack of associations with comorbid medical problems may suggest that the VA’s depression screening procedures have low sensitivity for identifying depression in CAD

The Performance of Step-Wise Group Screening Designs

Directory of Open Access Journals (Sweden)

M.M. Manene

2005-06-01

Full Text Available In this paper we evaluate the performance of step-wise group screening designs in which group-factors contain an equal number of factors in the initial step.  A usual assumption in group screening designs is that the directions of possible effects are known a-priori. In practice, however, this assumption is unreasonable. We shall examine step-wise group screening designs without errors in observations when this assumption is relaxed. We shall consider cancellations of effects within group-factors. The performance of step-wise group-screening designs shall then be compared with the performance of multistage group screening designs.

An Analysis of Mass Screening Strategies Using a Mathematical Model: Comparison of Breast Cancer Screening in Japan and the United States

Science.gov (United States)

Tsunematsu, Miwako; Kakehashi, Masayuki

2015-01-01

Background Although the United States Preventive Services Task Force (USPSTF) downgraded their recommendation for breast cancer screening for women aged 40–49 years in 2009, Japanese women in their 40s have been encouraged to attend breast cancer screenings since 2004. The aim of this study is to examine whether these different mass-screening strategies are justifiable by the different situations of these countries and to provide evidence for suitable judgment. Methods Performance of screening strategies (annual/biennial intervals; initiating/terminating ages) was evaluated using a mathematical model based on the natural history of breast cancer and the transition between its stages. Benefits (reduced number of deaths and extended average life expectancy) and harm (false-positives) associated with these strategies were calculated. Results Additional average life expectancy by including women in their 40s as participants were 13 days (26%) and 25 days (22%) in Japan and the United States, respectively, under the biennial screening condition; however, the respective increases in numbers of false-positive cases were 65% and 53% in Japan and the United States. Moreover, the number of screenings needed to detect one diagnosis or to avert one death was smaller when participants were limited to women of age 50 or over than when women in their 40s were included. The validity of including women in their 40s in Japan could not be determined without specifying the weight of harms compared to benefits. Conclusions Whether screening of women in their 40s in Japan is justifiable must be carefully determined based the quantitative balance of benefits and harms. PMID:25483105

Role of optometry school in single day large scale school vision testing

Science.gov (United States)

Anuradha, N; Ramani, Krishnakumar

2015-01-01

Background: School vision testing aims at identification and management of refractive errors. Large-scale school vision testing using conventional methods is time-consuming and demands a lot of chair time from the eye care professionals. A new strategy involving a school of optometry in single day large scale school vision testing is discussed. Aim: The aim was to describe a new approach of performing vision testing of school children on a large scale in a single day. Materials and Methods: A single day vision testing strategy was implemented wherein 123 members (20 teams comprising optometry students and headed by optometrists) conducted vision testing for children in 51 schools. School vision testing included basic vision screening, refraction, frame measurements, frame choice and referrals for other ocular problems. Results: A total of 12448 children were screened, among whom 420 (3.37%) were identified to have refractive errors. 28 (1.26%) children belonged to the primary, 163 to middle (9.80%), 129 (4.67%) to secondary and 100 (1.73%) to the higher secondary levels of education respectively. 265 (2.12%) children were referred for further evaluation. Conclusion: Single day large scale school vision testing can be adopted by schools of optometry to reach a higher number of children within a short span. PMID:25709271

Early stage animal hoarders: are these owners of large numbers of adequately cared for cats?

OpenAIRE

Ramos, D.; da Cruz, N. O.; Ellis, Sarah; Hernandez, J. A. E.; Reche-Junior, A.

2013-01-01

Animal hoarding is a spectrum-based condition in which hoarders are often reported to have had normal and appropriate pet-keeping habits in childhood and early adulthood. Historically, research has focused largely on well established clinical animal hoarders with little work targeted towards the onset and development of animal hoarding. This study investigated whether a Brazilian population of owners of what might typically be considered an excessive number (20 or more) of cats were more like...

"To Screen or not to Screen": Comparing the Health and Economic Benefits of Early Peanut Introduction Strategies in Five Countries.

Science.gov (United States)

Shaker, Marcus; Stukus, David; Chan, Edmond S; Fleischer, David M; Spergel, Jonathan M; Greenhawt, Matthew

2018-03-30

Early peanut introduction (EPI) in the first year of life is associated with reduced risk of developing peanut allergy in children with either severe eczema and/or egg allergy. However, EPI recommendations differ among countries with formal guidelines. Using simulation and Markov modeling over a 20-year horizon to attempt to explore optimal EPI strategies applied to the US population, we compared high-risk infant specific IgE peanut screening (US/Canadian) with the Australiasian Society for Clinical Immunology and Allergy (Australia/New Zealand) (ASCIA) and the United Kingdom Department of Health (UKDOH) published EPI approaches. Screening peanut skin testing of all children with early onset eczema and/or egg allergy before in-office peanut introduction was dominated by a no-screen approach, in terms of number of cases of peanut allergy prevented, QALY's, and healthcare costs, though screening resulted in a slightly lower rate of allergic reactions to peanut per-patient in high-risk children. Considering costs of peanut allergy in high-risk children, the per-patient cost of early introduction without screening over the model horizon was $6,556.69 (95%CI, $6,512.76-$6,600.62), compared with a cost of $7,576.32 (95%CI, $7,531.38-$7,621.26) for skin test screening prior to introduction. From a US societal perspective, screening prior to introduction cost $654,115,322 and resulted in 3,208 additional peanut allergy diagnoses. Both screening and non-screening approaches dominated deliberately delayed peanut introduction. A no-screening approach for EPI has superior health and economic benefits in terms of number of peanut allergy cases prevented, QALY's, and total health care costs compared to screening and in-office peanut introduction. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Spray-Deposited Large-Area Copper Nanowire Transparent Conductive Electrodes and Their Uses for Touch Screen Applications.

Science.gov (United States)

Chu, Hsun-Chen; Chang, Yen-Chen; Lin, Yow; Chang, Shu-Hao; Chang, Wei-Chung; Li, Guo-An; Tuan, Hsing-Yu

2016-05-25

Large-area conducting transparent conducting electrodes (TCEs) were prepared by a fast, scalable, and low-cost spray deposition of copper nanowire (CuNW) dispersions. Thin, long, and pure copper nanowires were obtained via the seed-mediated growth in an organic solvent-based synthesis. The mean length and diameter of nanowires are, respectively, 37.7 μm and 46 nm, corresponding to a high-mean-aspect ratio of 790. These wires were spray-deposited onto a glass substrate to form a nanowire conducting network which function as a TCE. CuNW TCEs exhibit high-transparency and high-conductivity since their relatively long lengths are advantageous in lowering in the sheet resistance. For example, a 2 × 2 cm(2) transparent nanowire electrode exhibits transmittance of T = 90% with a sheet resistance as low as 52.7 Ω sq(-1). Large-area sizes (>50 cm(2)) of CuNW TCEs were also prepared by the spray coating method and assembled as resistive touch screens that can be integrated with a variety of devices, including LED lighting array, a computer, electric motors, and audio electronic devices, showing the capability to make diverse sizes and functionalities of CuNW TCEs by the reported method.

People’s willingness to accept overdetection in cancer screening: population survey

Science.gov (United States)

Jones, Caroline; Yang, Yaling; Oke, Jason; Hewitson, Paul

2015-01-01

Objectives To describe the level of overdetection people would find acceptable in screening for breast, prostate, and bowel cancer and whether acceptability is influenced by the magnitude of the benefit from screening and the cancer specific harms from overdetection. Design Online survey. Women were presented with scenarios on breast and bowel cancer, men with scenarios on prostate and bowel cancer. For each particular cancer, we presented epidemiological information and described the treatment and its consequences. Secondly, we presented two different scenarios of benefit: one indicating a 10% reduction in cancer specific mortality and the second indicating a 50% reduction. Setting Online survey of the population in the United Kingdom. Participants Respondents were part of an existing panel of people who volunteer for online research and were invited by email or online marketing. We recruited 1000 respondents, representative for age and sex for the UK population. Main outcome measures Number of cases of overdetection people were willing to accept, ranging from 0-1000 (complete screened population) for each cancer modality and each scenario of benefit. Results There was large variability between respondents in the level of overdetection they would find acceptable, with medians ranging from 113 to 313 cases of overdetection per 1000 people screened. Across all scenarios, 4-7% of respondents indicated they would accept no overdetection at all compared with 7-14% who thought that it would be acceptable for the entire screened population to be overdetected. Acceptability in screening for bowel cancer was significantly lower than for breast and prostate cancer. People aged 50 or over accepted significantly less overdetection, whereas people with higher education levels accepted more; 29% of respondents had heard of overdetection before. Conclusions Acceptability of overdetection in cancer screening is variable. Invitations for screening should include clear information

The mathematics of a successful deconvolution: a quantitative assessment of mixture-based combinatorial libraries screened against two formylpeptide receptors.

Science.gov (United States)

Santos, Radleigh G; Appel, Jon R; Giulianotti, Marc A; Edwards, Bruce S; Sklar, Larry A; Houghten, Richard A; Pinilla, Clemencia

2013-05-30

In the past 20 years, synthetic combinatorial methods have fundamentally advanced the ability to synthesize and screen large numbers of compounds for drug discovery and basic research. Mixture-based libraries and positional scanning deconvolution combine two approaches for the rapid identification of specific scaffolds and active ligands. Here we present a quantitative assessment of the screening of 32 positional scanning libraries in the identification of highly specific and selective ligands for two formylpeptide receptors. We also compare and contrast two mixture-based library approaches using a mathematical model to facilitate the selection of active scaffolds and libraries to be pursued for further evaluation. The flexibility demonstrated in the differently formatted mixture-based libraries allows for their screening in a wide range of assays.

Screening of metal-organic frameworks for carbon dioxide capture from flue gas using a combined experimental and modeling approach.

Science.gov (United States)

Yazaydin, A Ozgür; Snurr, Randall Q; Park, Tae-Hong; Koh, Kyoungmoo; Liu, Jian; Levan, M Douglas; Benin, Annabelle I; Jakubczak, Paulina; Lanuza, Mary; Galloway, Douglas B; Low, John J; Willis, Richard R

2009-12-30

A diverse collection of 14 metal-organic frameworks (MOFs) was screened for CO(2) capture from flue gas using a combined experimental and modeling approach. Adsorption measurements are reported for the screened MOFs at room temperature up to 1 bar. These data are used to validate a generalized strategy for molecular modeling of CO(2) and other small molecules in MOFs. MOFs possessing a high density of open metal sites are found to adsorb significant amounts of CO(2) even at low pressure. An excellent correlation is found between the heat of adsorption and the amount of CO(2) adsorbed below 1 bar. Molecular modeling can aid in selection of adsorbents for CO(2) capture from flue gas by screening a large number of MOFs.

Direct and large eddy simulation of turbulent heat transfer at very low Prandtl number: Application to lead–bismuth flows

International Nuclear Information System (INIS)

Bricteux, L.; Duponcheel, M.; Winckelmans, G.; Tiselj, I.; Bartosiewicz, Y.

2012-01-01

Highlights: ► We perform direct and hybrid-large eddy simulations of high Reynolds and low Prandtl turbulent wall-bounded flows with heat transfer. ► We use a state-of-the-art numerical methods with low energy dissipation and low dispersion. ► We use recent multiscalesubgrid scale models. ► Important results concerning the establishment of near wall modeling strategy in RANS are provided. ► The turbulent Prandtl number that is predicted by our simulation is different than that proposed by some correlations of the literature. - Abstract: This paper deals with the issue of modeling convective turbulent heat transfer of a liquid metal with a Prandtl number down to 0.01, which is the order of magnitude of lead–bismuth eutectic in a liquid metal reactor. This work presents a DNS (direct numerical simulation) and a LES (large eddy simulation) of a channel flow at two different Reynolds numbers, and the results are analyzed in the frame of best practice guidelines for RANS (Reynolds averaged Navier–Stokes) computations used in industrial applications. They primarily show that the turbulent Prandtl number concept should be used with care and that even recent proposed correlations may not be sufficient.

Decision process in MCDM with large number of criteria and heterogeneous risk preferences

Directory of Open Access Journals (Sweden)

Jian Liu

Full Text Available A new decision process is proposed to address the challenge that a large number criteria in the multi-criteria decision making (MCDM problem and the decision makers with heterogeneous risk preferences. First, from the perspective of objective data, the effective criteria are extracted based on the similarity relations between criterion values and the criteria are weighted, respectively. Second, the corresponding types of theoretic model of risk preferences expectations will be built, based on the possibility and similarity between criterion values to solve the problem for different interval numbers with the same expectation. Then, the risk preferences (Risk-seeking, risk-neutral and risk-aversion will be embedded in the decision process. Later, the optimal decision object is selected according to the risk preferences of decision makers based on the corresponding theoretic model. Finally, a new algorithm of information aggregation model is proposed based on fairness maximization of decision results for the group decision, considering the coexistence of decision makers with heterogeneous risk preferences. The scientific rationality verification of this new method is given through the analysis of real case. Keywords: Heterogeneous, Risk preferences, Fairness, Decision process, Group decision

Correlates of mobile screen media use among children aged 0?8: protocol for a systematic review

OpenAIRE

Paudel, Susan; Leavy, Justine; Jancey, Jonine

2016-01-01

Background Childhood is a crucial period for shaping healthy behaviours; however, it currently appears to be dominated by screen time. A large proportion of young children do not adhere to the screen time recommendations, with the use of mobile screen devices becoming more common than fixed screens. Existing systematic reviews on correlates of screen time have focused largely on the traditional fixed screen devices such as television. Reviews specially focused on mobile screen media are almos...

Screening for oral cancer.

Science.gov (United States)

Jitender, Solanki; Sarika, Gupta; Varada, Hiremath R; Omprakash, Yadav; Mohsin, Khan

2016-11-01

Oral cancer is considered as a serious health problem resulting in high morbidity and mortality. Early detection and prevention play a key role in controlling the burden of oral cancer worldwide. The five-year survival rate of oral cancer still remains low and delayed diagnosis is considered as one of the major reasons. This increases the demand for oral screening. Currently, screening of oral cancer is largely based on visual examination. Various evidence strongly suggest the validity of visual inspection in reducing mortality in patients at risk for oral cancer. Simple visual examination is accompanied with adjunctive techniques for subjective interpretation of dysplastic changes. These include toluidine blue staining, brush biopsy, chemiluminescence and tissue autofluorescence. This review highlights the efficacy of various diagnostic methods in screening of oral cancer. © 2016 Old City Publishing, Inc.

Identifiability in N-mixture models: a large-scale screening test with bird data.

Science.gov (United States)

Kéry, Marc

2018-02-01

Binomial N-mixture models have proven very useful in ecology, conservation, and monitoring: they allow estimation and modeling of abundance separately from detection probability using simple counts. Recently, doubts about parameter identifiability have been voiced. I conducted a large-scale screening test with 137 bird data sets from 2,037 sites. I found virtually no identifiability problems for Poisson and zero-inflated Poisson (ZIP) binomial N-mixture models, but negative-binomial (NB) models had problems in 25% of all data sets. The corresponding multinomial N-mixture models had no problems. Parameter estimates under Poisson and ZIP binomial and multinomial N-mixture models were extremely similar. Identifiability problems became a little more frequent with smaller sample sizes (267 and 50 sites), but were unaffected by whether the models did or did not include covariates. Hence, binomial N-mixture model parameters with Poisson and ZIP mixtures typically appeared identifiable. In contrast, NB mixtures were often unidentifiable, which is worrying since these were often selected by Akaike's information criterion. Identifiability of binomial N-mixture models should always be checked. If problems are found, simpler models, integrated models that combine different observation models or the use of external information via informative priors or penalized likelihoods, may help. © 2017 by the Ecological Society of America.

Characterizing sampling and quality screening biases in infrared and microwave limb sounding

Science.gov (United States)

Millán, Luis F.; Livesey, Nathaniel J.; Santee, Michelle L.; von Clarmann, Thomas

2018-03-01

This study investigates orbital sampling biases and evaluates the additional impact caused by data quality screening for the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) and the Aura Microwave Limb Sounder (MLS). MIPAS acts as a proxy for typical infrared limb emission sounders, while MLS acts as a proxy for microwave limb sounders. These biases were calculated for temperature and several trace gases by interpolating model fields to real sampling patterns and, additionally, screening those locations as directed by their corresponding quality criteria. Both instruments have dense uniform sampling patterns typical of limb emission sounders, producing almost identical sampling biases. However, there is a substantial difference between the number of locations discarded. MIPAS, as a mid-infrared instrument, is very sensitive to clouds, and measurements affected by them are thus rejected from the analysis. For example, in the tropics, the MIPAS yield is strongly affected by clouds, while MLS is mostly unaffected. The results show that upper-tropospheric sampling biases in zonally averaged data, for both instruments, can be up to 10 to 30 %, depending on the species, and up to 3 K for temperature. For MIPAS, the sampling reduction due to quality screening worsens the biases, leading to values as large as 30 to 100 % for the trace gases and expanding the 3 K bias region for temperature. This type of sampling bias is largely induced by the geophysical origins of the screening (e.g. clouds). Further, analysis of long-term time series reveals that these additional quality screening biases may affect the ability to accurately detect upper-tropospheric long-term changes using such data. In contrast, MLS data quality screening removes sufficiently few points that no additional bias is introduced, although its penetration is limited to the upper troposphere, while MIPAS may cover well into the mid-troposphere in cloud-free scenarios. We emphasize that the

Conducting Universal Complete Mental Health Screening via Student Self-Report

Science.gov (United States)

Moore, Stephanie A.; Widales-Benitez, Oscar; Carnazzo, Katherine W.; Kim, Eui Kyung; Moffa, Kathryn; Dowdy, Erin

2015-01-01

Universal screening is increasingly becoming part of prevention and early intervention best practice in schools. Although the number of schools engaging in universal screening has increased over the past decade, emotional and behavioral problems are often their primary focus. Problem-focused screening, however, does not address positive…

Prioritizing multiple therapeutic targets in parallel using automated DNA-encoded library screening

Science.gov (United States)

Machutta, Carl A.; Kollmann, Christopher S.; Lind, Kenneth E.; Bai, Xiaopeng; Chan, Pan F.; Huang, Jianzhong; Ballell, Lluis; Belyanskaya, Svetlana; Besra, Gurdyal S.; Barros-Aguirre, David; Bates, Robert H.; Centrella, Paolo A.; Chang, Sandy S.; Chai, Jing; Choudhry, Anthony E.; Coffin, Aaron; Davie, Christopher P.; Deng, Hongfeng; Deng, Jianghe; Ding, Yun; Dodson, Jason W.; Fosbenner, David T.; Gao, Enoch N.; Graham, Taylor L.; Graybill, Todd L.; Ingraham, Karen; Johnson, Walter P.; King, Bryan W.; Kwiatkowski, Christopher R.; Lelièvre, Joël; Li, Yue; Liu, Xiaorong; Lu, Quinn; Lehr, Ruth; Mendoza-Losana, Alfonso; Martin, John; McCloskey, Lynn; McCormick, Patti; O'Keefe, Heather P.; O'Keeffe, Thomas; Pao, Christina; Phelps, Christopher B.; Qi, Hongwei; Rafferty, Keith; Scavello, Genaro S.; Steiginga, Matt S.; Sundersingh, Flora S.; Sweitzer, Sharon M.; Szewczuk, Lawrence M.; Taylor, Amy; Toh, May Fern; Wang, Juan; Wang, Minghui; Wilkins, Devan J.; Xia, Bing; Yao, Gang; Zhang, Jean; Zhou, Jingye; Donahue, Christine P.; Messer, Jeffrey A.; Holmes, David; Arico-Muendel, Christopher C.; Pope, Andrew J.; Gross, Jeffrey W.; Evindar, Ghotas

2017-07-01

The identification and prioritization of chemically tractable therapeutic targets is a significant challenge in the discovery of new medicines. We have developed a novel method that rapidly screens multiple proteins in parallel using DNA-encoded library technology (ELT). Initial efforts were focused on the efficient discovery of antibacterial leads against 119 targets from Acinetobacter baumannii and Staphylococcus aureus. The success of this effort led to the hypothesis that the relative number of ELT binders alone could be used to assess the ligandability of large sets of proteins. This concept was further explored by screening 42 targets from Mycobacterium tuberculosis. Active chemical series for six targets from our initial effort as well as three chemotypes for DHFR from M. tuberculosis are reported. The findings demonstrate that parallel ELT selections can be used to assess ligandability and highlight opportunities for successful lead and tool discovery.

Socioeconomic disparities in access to a hepatocellular carcinoma screening program in Brazil

Directory of Open Access Journals (Sweden)

Izabelle Venturini Signorelli

Full Text Available OBJECTIVES: Cirrhotic patients must receive an abdominal ultrasound every 6 months as part of hepatocellular carcinoma (HCC screening. The aim of this study was to assess if HCC screening was performed as recommended by the literature and to observe the differences between the private and public services in Brazil. METHODS: We analyzed data from the HCC screenings of 253 cirrhotic patients from the University Hospital (n=177 and private sector (n=76 in Vitória, ES, Brazil. RESULTS: Ultrasound screening was performed every 13.1 months on average (SD 9.02. In 37 out of 253 patients, the screenings were performed close to the recommended frequency; 16 were performed every 6 months, and 21 were mostly performed during the follow-up period every 6 months. In the remaining 216 cases, ultrasounds were not performed according to the guidelines; for 106 patients, less than 50% of all ultrasounds were performed every 6 months and 110 patients showed an interval greater than one year. Patients from the private sector received ultrasound screenings near the ideal in 28.9% of cases, while patients from the University Hospital received ultrasounds in only 8.4% of cases (p<0.0001. HCC was diagnosed in 30 patients (11.8%. For these 30 patients, 11 screenings were properly performed within 6 months (36.6% and only 1 out of the 11 (9% met the criteria for transplant. In the remaining 19 patients who did not receive the screening within 6 months, 6 (31.5% did not meet the criteria for transplant. CONCLUSION: HCC screening in our environment was irregularly performed, mainly in the public service setting, which prevented early diagnosis in a large number of patients.

On the Convergence and Law of Large Numbers for the Non-Euclidean Lp -Means

Directory of Open Access Journals (Sweden)

George Livadiotis

2017-05-01

Full Text Available This paper describes and proves two important theorems that compose the Law of Large Numbers for the non-Euclidean L p -means, known to be true for the Euclidean L 2 -means: Let the L p -mean estimator, which constitutes the specific functional that estimates the L p -mean of N independent and identically distributed random variables; then, (i the expectation value of the L p -mean estimator equals the mean of the distributions of the random variables; and (ii the limit N → ∞ of the L p -mean estimator also equals the mean of the distributions.

Prioritizing Chemicals and Data Requirements for Screening-Level Exposure and Risk Assessment

Science.gov (United States)

Brown, Trevor N.; Wania, Frank; Breivik, Knut; McLachlan, Michael S.

2012-01-01

Background: Scientists and regulatory agencies strive to identify chemicals that may cause harmful effects to humans and the environment; however, prioritization is challenging because of the large number of chemicals requiring evaluation and limited data and resources. Objectives: We aimed to prioritize chemicals for exposure and exposure potential and obtain a quantitative perspective on research needs to better address uncertainty in screening assessments. Methods: We used a multimedia mass balance model to prioritize > 12,000 organic chemicals using four far-field human exposure metrics. The propagation of variance (uncertainty) in key chemical information used as model input for calculating exposure metrics was quantified. Results: Modeled human concentrations and intake rates span approximately 17 and 15 orders of magnitude, respectively. Estimates of exposure potential using human concentrations and a unit emission rate span approximately 13 orders of magnitude, and intake fractions span 7 orders of magnitude. The actual chemical emission rate contributes the greatest variance (uncertainty) in exposure estimates. The human biotransformation half-life is the second greatest source of uncertainty in estimated concentrations. In general, biotransformation and biodegradation half-lives are greater sources of uncertainty in modeled exposure and exposure potential than chemical partition coefficients. Conclusions: Mechanistic exposure modeling is suitable for screening and prioritizing large numbers of chemicals. By including uncertainty analysis and uncertainty in chemical information in the exposure estimates, these methods can help identify and address the important sources of uncertainty in human exposure and risk assessment in a systematic manner. PMID:23008278

Prioritizing chemicals and data requirements for screening-level exposure and risk assessment.

Science.gov (United States)

Arnot, Jon A; Brown, Trevor N; Wania, Frank; Breivik, Knut; McLachlan, Michael S

2012-11-01

Scientists and regulatory agencies strive to identify chemicals that may cause harmful effects to humans and the environment; however, prioritization is challenging because of the large number of chemicals requiring evaluation and limited data and resources. We aimed to prioritize chemicals for exposure and exposure potential and obtain a quantitative perspective on research needs to better address uncertainty in screening assessments. We used a multimedia mass balance model to prioritize > 12,000 organic chemicals using four far-field human exposure metrics. The propagation of variance (uncertainty) in key chemical information used as model input for calculating exposure metrics was quantified. Modeled human concentrations and intake rates span approximately 17 and 15 orders of magnitude, respectively. Estimates of exposure potential using human concentrations and a unit emission rate span approximately 13 orders of magnitude, and intake fractions span 7 orders of magnitude. The actual chemical emission rate contributes the greatest variance (uncertainty) in exposure estimates. The human biotransformation half-life is the second greatest source of uncertainty in estimated concentrations. In general, biotransformation and biodegradation half-lives are greater sources of uncertainty in modeled exposure and exposure potential than chemical partition coefficients. Mechanistic exposure modeling is suitable for screening and prioritizing large numbers of chemicals. By including uncertainty analysis and uncertainty in chemical information in the exposure estimates, these methods can help identify and address the important sources of uncertainty in human exposure and risk assessment in a systematic manner.

A Multimedia Child Developmental Screening Checklist: Design and Validation.

Science.gov (United States)

Cheng, Hsin-Yi Kathy; Chen, Li-Ying; Cheng, Chih-Hsiu; Ju, Yan-Ying; Chen, Chia-Ling; Tseng, Kevin C

2016-10-24

Identifying disability early in life confers long-term benefits for children. The Taipei City Child Development Screening tool, second version (Taipei II) provides checklists for 13 child age groups from 4 months to 6 years. However, the usability of a text-based screening tool largely depends on the literacy level and logical reasoning ability of the caregivers, as well as language barriers caused by increasing numbers of immigrants. The objectives of this study were to (1) design and develop a Web-based multimedia version of the current Taipei II developmental screening tool, and (2) investigate the measurement equivalence of this multimedia version to the original paper-based version. To develop the multimedia version of Taipei II, a team of experts created illustrations, translations, and dubbing of the original checklists. The developmental screening test was administered to a total of 390 primary caregivers of children aged between 4 months and 6 years. Psychometric testing revealed excellent agreement between the paper and multimedia versions of Taipei II. Good to excellent reliabilities were demonstrated for all age groups for both the cross-mode similarity (mode intraclass correlation range 0.85-0.96) and the test-retest reliability (r=.93). Regarding the usability, the mean score was 4.80 (SD 0.03), indicating that users were satisfied with their multimedia website experience. The multimedia tool produced essentially equivalent results to the paper-based tool. In addition, it had numerous advantages, such as it can facilitate active participation and promote early screening of target populations. Clinicaltrials.gov NCT02359591; https://clinicaltrials.gov/ct2/show/NCT02359591 (Archived by WebCite at http://www.webcitation.org/6l21mmdNn).

Tuberculosis screening in patients with HIV

DEFF Research Database (Denmark)

Bjerrrum, Stephanie; Bonsu, Frank; Hanson-Nortey, Nii Nortey

2016-01-01

BACKGROUND: Tuberculosis screening of people living with HIV (PLHIV) can contribute to early tuberculosis diagnosis and improved patient outcomes. Evidence-based guidelines for tuberculosis screening are available, but literature assessing their implementation and the quality of clinical practice...... is scarce. OBJECTIVES: To assess tuberculosis screening practices and the effectiveness of audit and performance feedback to improve quality of tuberculosis screening at HIV care clinics in Ghana. DESIGN: Healthcare providers at 10 large HIV care clinics prospectively registered patient consultations during...... May and October 2014, before and after a performance feedback intervention in August 2014. The outcomes of interest were overall tuberculosis suspicion rate during consultations and provider adherence to the International Standards for Tuberculosis Care and the World Health Organizations' guidelines...

CRISPR genetic screens to discover host-virus interactions.

Science.gov (United States)

McDougall, William M; Perreira, Jill M; Reynolds, Erin C; Brass, Abraham L

2018-04-01

Viruses impose an immense burden on human health. With the goal of treating and preventing viral infections, researchers have carried out genetic screens to improve our understanding of viral dependencies and identify potential anti-viral strategies. The emergence of CRISPR genetic screening tools has facilitated this effort by enabling host-virus screens to be undertaken in a more versatile and fidelitous manner than previously possible. Here we review the growing number of CRISPR screens which continue to increase our understanding of host-virus interactions. Copyright © 2018 Elsevier B.V. All rights reserved.

Cost Analysis of Universal Screening vs. Risk Factor-Based Screening for Methicillin-Resistant Staphylococcus aureus (MRSA.

Directory of Open Access Journals (Sweden)

Virginia R Roth

Full Text Available The literature remains conflicted regarding the most effective way to screen for MRSA. This study was designed to assess costs associated with universal versus risk factor-based screening for the reduction of nosocomial MRSA transmission.The study was conducted at The Ottawa Hospital, a large multi-centre tertiary care facility with approximately 47,000 admissions annually. From January 2006-December 2007, patients underwent risk factor-based screening for MRSA on admission. From January 2008 to August 2009 universal MRSA screening was implemented. A comparison of costs incurred during risk factor-based screening and universal screening was conducted. The model incorporated probabilities relating to the likelihood of being tested and the results of polymerase chain reaction (PCR testing with associated effects in terms of MRSA bacteremia and true positive and negative test results. Inputted costs included laboratory testing, contact precautions and infection control, private room costs, housekeeping, and length of hospital stay. Deterministic sensitivity analyses were conducted.The risk factor-based MRSA screening program screened approximately 30% of admitted patients and cost the hospital over $780 000 annually. The universal screening program screened approximately 83% of admitted patients and cost over $1.94 million dollars, representing an excess cost of $1.16 million per year. The estimated additional cost per patient screened was $17.76.This analysis demonstrated that a universal MRSA screening program was costly from a hospital perspective and was previously known to not be clinically effective at reducing MRSA transmission. These results may be useful to inform future model-based economic analyses of MRSA interventions.

An evaluation of touchscreen versus keyboard/mouse interaction for large screen process control displays.

Science.gov (United States)

Noah, Benjamin; Li, Jingwen; Rothrock, Ling

2017-10-01

The objectives of this study were to test the effect of interaction device on performance in a process control task (managing a tank farm). The study compared the following two conditions: a) 4K-resolution 55" screen with a 21" touchscreen versus b) 4K-resolution 55″ screen with keyboard/mouse. The touchscreen acted both as an interaction device for data entry and navigation and as an additional source of information. A within-subject experiment was conducted among 20 college engineering students. A primary task of preventing tanks from overfilling as well as a secondary task of manual logging with situation awareness questions were designed for the study. Primary Task performance (including tank level at discharge, number of tank discharged and performance score), Secondary Task Performance (including Tank log count, performance score), system interaction times, subjective workload, situation awareness questionnaire, user experience survey regarding usability and condition comparison were used as the measures. Parametric data resulted in two metrics statistically different means between the two conditions: The 4K-keyboard condition resulted in faster Detection + Navigation time compared to the 4K-touchscreen condition, by about 2 s, while participants within the 4K-touchscreen condition were about 2 s faster in data entry than in the 4K-keyboard condition. No significant results were found for: performance on the secondary task, situation awareness, and workload. Additionally, no clear significant differences were found in the non-parametric data analysis. However, participants showed a slight preference for the 4K-touchscreen condition compared to the 4K-keyboard condition in subjective responses in comparing the conditions. Introducing the touchscreen as an additional/alternative input device showed to have an effect in interaction times, which suggests that proper design considerations need to be made. While having values shown on the interaction device

PET in cancer screening: a controversial imaging

International Nuclear Information System (INIS)

Su Minggang; Tan Tianzhi

2012-01-01

Malignancy has been one of the most dangerous threats to human health. Early diagnosis and treatment are key factors for improving prognosis. Cancer screening is an important way to detect early stage cancer and precancerous lesion. PET has been used increasingly in cancer screening in accordance with the requirement of the public. Though a great number of data show that PET can find some subclinical malignancy, yet as a cancer screening modality, PET is still controversial in contemporary medical practice. The aim of this article is to review the application status and existing problem of PET in cancer screening, and to offer some recognition and view about cancer srceening. (authors)

Screen-printing ink transfer in a sexual assault case.

Science.gov (United States)

Amick, Janeice F; Beheim, Chris W

2002-05-01

Yellow plastic-like particles were discovered on the clothing and body of a sexual assault victim. These particles were later associated to an athletic jersey with flaking yellow screen-printed numbers and letters, worn by the suspect. Depending on its intended substrate, screen-print ink can vary in color and composition. Particles dislodged from screen-printed garments may exhibit fabric impressions. Screen-printed clothing, commonly encountered in forensic casework, should be viewed as a potential source of trace evidence.

Using NFC technology for fast-tracking large-siza multi-touch screens

OpenAIRE

Muñoz-Organero, Mario; Opoku, Samuel King

2011-01-01

Multi-touch technology interfaces are becoming ubiquitous since their integration in smart-phones, tablets and many consumer electronics devices. Depending on the size of the tangible interface, the computing resource restrictions and the resolution required, there are different technological alternatives for multi-touch screens such as camera based systems, capacity, resistive or pressure sensing systems or LED based systems. This paper presents a different alternative to d...

The Ramsey numbers of large cycles versus small wheels

NARCIS (Netherlands)

Surahmat,; Baskoro, E.T.; Broersma, H.J.

2004-01-01

For two given graphs G and H, the Ramsey number R(G;H) is the smallest positive integer N such that for every graph F of order N the following holds: either F contains G as a subgraph or the complement of F contains H as a subgraph. In this paper, we determine the Ramsey number R(Cn;Wm) for m = 4

Summary of experience from a large number of construction inspections; Wind power plant projects; Erfarenhetsaaterfoering fraan entreprenadbesiktningar

Energy Technology Data Exchange (ETDEWEB)

Andersson, Bertil; Holmberg, Rikard

2010-08-15

This report presents a summary of experience from a large number of construction inspections of wind power projects. The working method is based on the collection of construction experience in form of questionnaires. The questionnaires were supplemented by a number of in-depth interviews to understand more in detail what is perceived to be a problem and if there were suggestions for improvements. The results in this report is based on inspection protocols from 174 wind turbines, which corresponds to about one-third of the power plants built in the time period. In total the questionnaires included 4683 inspection remarks as well as about one hundred free text comments. 52 of the 174 inspected power stations were rejected, corresponding to 30%. It has not been possible to identify any over represented type of remark as a main cause of rejection, but the rejection is usually based on a total number of remarks that is too large. The average number of remarks for a power plant is 27. Most power stations have between 20 and 35 remarks. The most common remarks concern shortcomings in marking and documentation. These are easily adjusted, and may be regarded as less serious. There are, however, a number of remarks which are recurrent and quite serious, mainly regarding gearbox, education and lightning protection. Usually these are also easily adjusted, but the consequences if not corrected can be very large. The consequences may be either shortened life of expensive components, e.g. oil problems in gear boxes, or increased probability of serious accidents, e.g. maladjusted lightning protection. In the report, comparison between power stations with various construction period, size, supplier, geography and topography is also presented. The general conclusion is that the differences are small. The results of the evaluation of questionnaires correspond well with the result of the in-depth interviews with clients. The problem that clients agreed upon as the greatest is the lack

Review of neonatal screening programme for phenylketonuria.

Science.gov (United States)

Smith, I; Cook, B; Beasley, M

1991-01-01

OBJECTIVE--To review the neonatal screening programme during 1984-8. DESIGN--Analysis of data from screening laboratories and paediatricians. SUBJECTS--All live births in United Kingdom. MAIN OUTCOME MEASURES--Structure of programme; number of infants tested and number with phenylketonuria; number of infants missed; ages at testing and treatment. RESULTS--The proportion of infants tested approached 100%. The incidence of phenylketonuria was 11.7/100,000 births (445 subjects): 273 had classic phenylketonuria and three had defects of cofactor metabolism. One child with phenylketonuria was known to have been missed compared with three in 1979-83 and six in 1974-8. Seven subjects had been missed over the 15 years due to negative test results. All seven had been tested with the bacterial inhibition assay, although only 53% of infants had been so tested; the difference between the expected and observed proportion was significant (Fisher's exact test, p = 0.017). Eleven infants with classic phenylketonuria were not tested by 14 days of age and 23 (8%) did not start treatment until after 20 days, an improvement compared with 36 (15%) in 1979-83. There were, however, wide regional variations (0% to 27% treated after 20 days). CONCLUSION--The screening programme achieves high coverage and effectiveness, although some children are still missed. A national practice for screening may help reduce regional variations. PMID:1912773

A Genome-Wide Association Study in Large White and Landrace Pig Populations for Number Piglets Born Alive

Science.gov (United States)

Bergfelder-Drüing, Sarah; Grosse-Brinkhaus, Christine; Lind, Bianca; Erbe, Malena; Schellander, Karl; Simianer, Henner; Tholen, Ernst

2015-01-01

The number of piglets born alive (NBA) per litter is one of the most important traits in pig breeding due to its influence on production efficiency. It is difficult to improve NBA because the heritability of the trait is low and it is governed by a high number of loci with low to moderate effects. To clarify the biological and genetic background of NBA, genome-wide association studies (GWAS) were performed using 4,012 Large White and Landrace pigs from herdbook and commercial breeding companies in Germany (3), Austria (1) and Switzerland (1). The animals were genotyped with the Illumina PorcineSNP60 BeadChip. Because of population stratifications within and between breeds, clusters were formed using the genetic distances between the populations. Five clusters for each breed were formed and analysed by GWAS approaches. In total, 17 different significant markers affecting NBA were found in regions with known effects on female reproduction. No overlapping significant chromosome areas or QTL between Large White and Landrace breed were detected. PMID:25781935

A genome-wide association study in large white and landrace pig populations for number piglets born alive.

Directory of Open Access Journals (Sweden)

Sarah Bergfelder-Drüing

Full Text Available The number of piglets born alive (NBA per litter is one of the most important traits in pig breeding due to its influence on production efficiency. It is difficult to improve NBA because the heritability of the trait is low and it is governed by a high number of loci with low to moderate effects. To clarify the biological and genetic background of NBA, genome-wide association studies (GWAS were performed using 4,012 Large White and Landrace pigs from herdbook and commercial breeding companies in Germany (3, Austria (1 and Switzerland (1. The animals were genotyped with the Illumina PorcineSNP60 BeadChip. Because of population stratifications within and between breeds, clusters were formed using the genetic distances between the populations. Five clusters for each breed were formed and analysed by GWAS approaches. In total, 17 different significant markers affecting NBA were found in regions with known effects on female reproduction. No overlapping significant chromosome areas or QTL between Large White and Landrace breed were detected.

The effectiveness and cost-effectiveness of screening for active tuberculosis among migrants in the EU/EEA: a systematic review.

Science.gov (United States)

Greenaway, Christina; Pareek, Manish; Abou Chakra, Claire-Nour; Walji, Moneeza; Makarenko, Iuliia; Alabdulkarim, Balqis; Hogan, Catherine; McConnell, Ted; Scarfo, Brittany; Christensen, Robin; Tran, Anh; Rowbotham, Nick; Noori, Teymur; van der Werf, Marieke J; Pottie, Kevin; Matteelli, Alberto; Zenner, Dominik; Morton, Rachael L

2018-04-01

The foreign-born population make up an increasing and large proportion of tuberculosis (TB) cases in European Union/European Economic Area (EU/EEA) low-incidence countries and challenge TB elimination efforts. Methods : We conducted a systematic review to determine effectiveness (yield and performance of chest radiography (CXR) to detect active TB, treatment outcomes and acceptance of screening) and a second systematic review on cost-effectiveness of screening for active TB among migrants living in the EU/EEA. Results : We identified six systematic reviews, one report and three individual studies that addressed our aims. CXR was highly sensitive (98%) but only moderately specific (75%). The yield of detecting active TB with CXR screening among migrants was 350 per 100,000 population overall but ranged widely by host country (110-2,340), migrant type (170-1,192), TB incidence in source country (19-336) and screening setting (220-1,720). The CXR yield was lower (19.6 vs 336/100,000) and the numbers needed to screen were higher (5,076 vs 298) among migrants from source countries with lower TB incidence (≤ 50 compared with ≥ 350/100,000). Cost-effectiveness was highest among migrants originating from high (> 120/100,000) TB incidence countries. The foreign-born had similar or better TB treatment outcomes than those born in the EU/EEA. Acceptance of CXR screening was high (85%) among migrants. Discussion : Screening programmes for active TB are most efficient when targeting migrants from higher TB incidence countries. The limited number of studies identified and the heterogeneous evidence highlight the need for further data to inform screening programmes for migrants in the EU/EEA.

Developing the Biomolecular Screening Facility at the EPFL into the Chemical Biology Screening Platform for Switzerland.

Science.gov (United States)

Turcatti, Gerardo

2014-05-01

The Biomolecular Screening Facility (BSF) is a multidisciplinary laboratory created in 2006 at the Ecole Polytechnique Federale de Lausanne (EPFL) to perform medium and high throughput screening in life sciences-related projects. The BSF was conceived and developed to meet the needs of a wide range of researchers, without privileging a particular biological discipline or therapeutic area. The facility has the necessary infrastructure, multidisciplinary expertise and flexibility to perform large screening programs using small interfering RNAs (siRNAs) and chemical collections in the areas of chemical biology, systems biology and drug discovery. In the framework of the National Centres of Competence in Research (NCCR) Chemical Biology, the BSF is hosting 'ACCESS', the Academic Chemical Screening Platform of Switzerland that provides the scientific community with chemical diversity, screening facilities and know-how in chemical genetics. In addition, the BSF started its own applied research axes that are driven by innovation in thematic areas related to preclinical drug discovery and discovery of bioactive probes.

Microfluidic glycosyl hydrolase screening for biomass-to-biofuel conversion.

Science.gov (United States)

Bharadwaj, Rajiv; Chen, Zhiwei; Datta, Supratim; Holmes, Bradley M; Sapra, Rajat; Simmons, Blake A; Adams, Paul D; Singh, Anup K

2010-11-15

The hydrolysis of biomass to fermentable sugars using glycosyl hydrolases such as cellulases and hemicellulases is a limiting and costly step in the conversion of biomass to biofuels. Enhancement in hydrolysis efficiency is necessary and requires improvement in both enzymes and processing strategies. Advances in both areas in turn strongly depend on the progress in developing high-throughput assays to rapidly and quantitatively screen a large number of enzymes and processing conditions. For example, the characterization of various cellodextrins and xylooligomers produced during the time course of saccharification is important in the design of suitable reactors, enzyme cocktail compositions, and biomass pretreatment schemes. We have developed a microfluidic-chip-based assay for rapid and precise characterization of glycans and xylans resulting from biomass hydrolysis. The technique enables multiplexed separation of soluble cellodextrins and xylose oligomers in around 1 min (10-fold faster than HPLC). The microfluidic device was used to elucidate the mode of action of Tm_Cel5A, a novel cellulase from hyperthermophile Thermotoga maritima . The results demonstrate that the cellulase is active at 80 °C and effectively hydrolyzes cellodextrins and ionic-liquid-pretreated switchgrass and Avicel to glucose, cellobiose, and cellotriose. The proposed microscale approach is ideal for quantitative large-scale screening of enzyme libraries for biomass hydrolysis, for development of energy feedstocks, and for polysaccharide sequencing.

Determinants of polyp Size in patients undergoing screening colonoscopy

Directory of Open Access Journals (Sweden)

Maisonneuve Patrick

2011-09-01

Full Text Available Abstract Background Pre-existing polyps, especially large polyps, are known to be the major source for colorectal cancer, but there is limited available information about factors that are associated with polyp size and polyp growth. We aim to determine factors associated with polyp size in different age groups. Methods Colonoscopy data were prospectively collected from 67 adult gastrointestinal practice sites in the United States between 2002 and 2007 using a computer-generated endoscopic report form. Data were transmitted to and stored in a central data repository, where all asymptomatic white (n = 78352 and black (n = 4289 patients who had a polyp finding on screening colonoscopy were identified. Univariate and multivariate analysis of age, gender, performance site, race, polyp location, number of polyps, and family history as risk factors associated with the size of the largest polyp detected at colonoscopy. Results In both genders, size of the largest polyp increased progressively with age in all age groups (P P Conclusions In both genders there is a significant increase in polyp size detected during screening colonoscopy with increasing age. Important additional risk factors associated with increasing polyp size are gender, race, polyp location, and number of polyps, with polyp multiplicity being the strongest risk factor. Previous family history of bowel cancer was not a risk factor.

Systematic screening of isogenic cancer cells identifies DUSP6 as context-specific synthetic lethal target in melanoma

DEFF Research Database (Denmark)

Wittig-Blaich, Stephanie; Wittig, Rainer; Schmidt, Steffen

2017-01-01

Next-generation sequencing has dramatically increased genome-wide profiling options and conceptually initiates the possibility for personalized cancer therapy. State-of-the-art sequencing studies yield large candidate gene sets comprising dozens or hundreds of mutated genes. However, few technolo......Next-generation sequencing has dramatically increased genome-wide profiling options and conceptually initiates the possibility for personalized cancer therapy. State-of-the-art sequencing studies yield large candidate gene sets comprising dozens or hundreds of mutated genes. However, few...... technologies are available for the systematic downstream evaluation of these results to identify novel starting points of future cancer therapies. We improved and extended a site-specific recombination-based system for systematic analysis of the individual functions of a large number of candidate genes......, a library of 108 isogenic melanoma cell lines was constructed and 8 genes were identified that significantly reduced viability in a discovery screen and in an independent validation screen. Here, we demonstrate the broad applicability of this recombination-based method and we proved its potential...

Red reflex screening in New Zealand: a large survey of practices and attitudes in the Auckland region.

Science.gov (United States)

Raoof, Naz; Dai, Shuan

2016-07-15

Red reflex testing forms an essential part of newborn (within the first week of life) and infant (6 weeks of age) screening in New Zealand, as outlined in the Well Child/Tamariki Ora handbook. This survey of practitioners undertaking red reflex screening aimed to determine current practices and attitudes of screeners, as well as any barriers to screening. A short, multiple-choice, on-line questionnaire was sent to approximately 1,500 health care professionals undertaking red reflex screening, over a 4-week period. Four hundred and eighty-three survey responses were received from 267 GPs (55.4%), 153 midwives (31.7%), and 50 paediatricians (10.4%). Thirty-six respondents (7.8%) performed red reflex screening only when they had time to do so, 13 (2.8%) only undertook this when there were concerns raised by the parents. Most respondents (97.3%) used an ophthalmoscope to perform screening. Seventynine respondents (16.6%) felt they were "not sure/underconfident" at performing this test. Only 83 of 479 respondents (17.3%) had received any formal training. The development of an online resource or practical 'refresher' sessions would be well received and likely to improve current practices.

Constraining screened fifth forces with the electron magnetic moment

Science.gov (United States)

Brax, Philippe; Davis, Anne-Christine; Elder, Benjamin; Wong, Leong Khim

2018-04-01

Chameleon and symmetron theories serve as archetypal models for how light scalar fields can couple to matter with gravitational strength or greater, yet evade the stringent constraints from classical tests of gravity on Earth and in the Solar System. They do so by employing screening mechanisms that dynamically alter the scalar's properties based on the local environment. Nevertheless, these do not hide the scalar completely, as screening leads to a distinct phenomenology that can be well constrained by looking for specific signatures. In this work, we investigate how a precision measurement of the electron magnetic moment places meaningful constraints on both chameleons and symmetrons. Two effects are identified: First, virtual chameleons and symmetrons run in loops to generate quantum corrections to the intrinsic value of the magnetic moment—a common process widely considered in the literature for many scenarios beyond the Standard Model. A second effect, however, is unique to scalar fields that exhibit screening. A scalar bubblelike profile forms inside the experimental vacuum chamber and exerts a fifth force on the electron, leading to a systematic shift in the experimental measurement. In quantifying this latter effect, we present a novel approach that combines analytic arguments and a small number of numerical simulations to solve for the bubblelike profile quickly for a large range of model parameters. Taken together, both effects yield interesting constraints in complementary regions of parameter space. While the constraints we obtain for the chameleon are largely uncompetitive with those in the existing literature, this still represents the tightest constraint achievable yet from an experiment not originally designed to search for fifth forces. We break more ground with the symmetron, for which our results exclude a large and previously unexplored region of parameter space. Central to this achievement are the quantum correction terms, which are able to

Screening and ranking Alberta oil pools for CO{sub 2} flooding and sequestration

Energy Technology Data Exchange (ETDEWEB)

Shaw, J.C. [Adams Pearson Associates Inc., Calgary, AB (Canada); Bachu, S. [Alberta Energy and Utilities Board, Calgary, AB (Canada)

2001-06-01

This paper presented the results of a technical screening program using Excel VBA to successfully screen and rank a very large number of oil pools for enhanced oil recovery using carbon dioxide (CO{sub 2}) flooding. A total of 6 ranking parameters were used, including API gravity of oil, residual oil saturation, ratio between reservoir pressure and minimum miscibility pressure, reservoir temperature, net pay thickness and porosity. The screening program provided a technical ranking of approximately 8,800 Alberta pools in less than 2 minutes. After compilation of the Alberta oil pools, it was determined that most of the deep carbonate oil pools are excellent candidates for CO{sub 2} miscible flooding. Other Devonian carbonate pools were also ranked as having high potential for the process. An environmental benefit of CO{sub 2} miscible flooding process is that carbon sequestration has the potential to reduce anthropogenic carbon dioxide emissions from reaching the atmosphere. Ongoing studies are currently addressing CO{sub 2} capture and transportation, making EOR technology viable for maintaining light oil production in western Canada. 11 refs., 7 tabs., 1 fig.

Empirical study of supervised gene screening

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Ma Shuangge

2006-12-01

Full Text Available Abstract Background Microarray studies provide a way of linking variations of phenotypes with their genetic causations. Constructing predictive models using high dimensional microarray measurements usually consists of three steps: (1 unsupervised gene screening; (2 supervised gene screening; and (3 statistical model building. Supervised gene screening based on marginal gene ranking is commonly used to reduce the number of genes in the model building. Various simple statistics, such as t-statistic or signal to noise ratio, have been used to rank genes in the supervised screening. Despite of its extensive usage, statistical study of supervised gene screening remains scarce. Our study is partly motivated by the differences in gene discovery results caused by using different supervised gene screening methods. Results We investigate concordance and reproducibility of supervised gene screening based on eight commonly used marginal statistics. Concordance is assessed by the relative fractions of overlaps between top ranked genes screened using different marginal statistics. We propose a Bootstrap Reproducibility Index, which measures reproducibility of individual genes under the supervised screening. Empirical studies are based on four public microarray data. We consider the cases where the top 20%, 40% and 60% genes are screened. Conclusion From a gene discovery point of view, the effect of supervised gene screening based on different marginal statistics cannot be ignored. Empirical studies show that (1 genes passed different supervised screenings may be considerably different; (2 concordance may vary, depending on the underlying data structure and percentage of selected genes; (3 evaluated with the Bootstrap Reproducibility Index, genes passed supervised screenings are only moderately reproducible; and (4 concordance cannot be improved by supervised screening based on reproducibility.

Assessing the Effectiveness of Functional Genetic Screens for the Identification of Bioactive Metabolites

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Staffan Kjelleberg

2012-12-01

Full Text Available A common limitation for the identification of novel activities from functional (meta genomic screens is the low number of active clones detected relative to the number of clones screened. Here we demonstrate that constructing libraries with strains known to produce bioactives can greatly enhance the screening efficiency, by increasing the “hit-rate” and unmasking multiple activities from the same bacterial source.

Screening for pulmonary arterial hypertension in systemic sclerosis

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J-L. Vachiéry

2009-09-01

Full Text Available The onset and progression of pulmonary arterial hypertension (PAH in patients with systemic sclerosis (SSc can be particularly aggressive; however, effective treatments are available. Therefore, early identification of patients with suspected PAH, confirmation of diagnosis, and intervention is essential. PAH may be challenging to diagnose in its earliest stages, particularly in populations that have multiple causes of breathlessness, and, therefore, screening is required. The optimal screening tools and methodology are, as yet, unknown, and this is confounded by a lack of consensus over which patients to screen. Current practice favours annual screening of all SSc patients using Doppler echocardiography to detect elevated right heart pressures. This will typically identify most patients with the various forms of pulmonary hypertension found in SSc. The optimum thresholds for Doppler echocardiography are still subject to investigation, especially for patients with mild pulmonary hypertension, and this technique may, therefore, yield a significant number of false-positives and a currently unknown number of false-negatives. Confirmatory right heart catheterisation remains necessary in all suspected cases. Further research is needed to identify the optimal tools and the screening approach with greatest specificity and selectivity.

What are key factors influencing malnutrition screening in community-dwelling elderly populations by general practitioners? A large cross-sectional survey in two areas of France.

Science.gov (United States)

Gaboreau, Y; Imbert, P; Jacquet, J-P; Marchand, O; Couturier, P; Gavazzi, G

2013-11-01

Malnutrition is associated with a high morbi-mortality in elderly populations and their institutionalization at an early stage. The incidence is well known despite being often under-diagnosed in primary care. General practitioners (GPs) have a key role in home care. What are the factors affecting malnutrition-screening implementation by French GPs? We conducted a cross-sectional survey in two areas in the southeast of France (Savoie and Isère). In May 2008, an anonymized survey was sent by e-mail and/or post to all GPs with a large clinical practice. Two months later, reminder letters were sent. Potential barriers were measured by dichotomous scale. On GPs' characteristics (socio-demographic, medical training, geriatric practice and knowledge), multiple regression logistic was performed to identify others factors affecting malnutrition screening. In all, 493 GPs (26.85%) answered and 72.2% felt that malnutrition screening was useful although only 26.6% implemented it each year and 11.9% every 2-5 years. The main barriers to the implementation were patient selection (60.4%) and forgetting to screen (26.6%). Minor barriers were lack of knowledge (19.5%) or time (15%). New factors were identified: unsuitable working conditions (19.1%), insufficient motivation (6.8%) or technical support (7.2%). The quality of malnutrition information received was found to be the only promoter of annual screening (odds ratio=1.44 (1.087-1.919); P=0.011). This survey is the first in France to reveal GPs' factors affecting malnutrition implementation. New obstacles were identified in this survey. The hope of implementing regular malnutrition screening by GPs seems to lie with the quality of malnutrition information received.

Large-scale functional RNAi screen in C. elegans identifies genes that regulate the dysfunction of mutant polyglutamine neurons.

Science.gov (United States)

Lejeune, François-Xavier; Mesrob, Lilia; Parmentier, Frédéric; Bicep, Cedric; Vazquez-Manrique, Rafael P; Parker, J Alex; Vert, Jean-Philippe; Tourette, Cendrine; Neri, Christian

2012-03-13

A central goal in Huntington's disease (HD) research is to identify and prioritize candidate targets for neuroprotective intervention, which requires genome-scale information on the modifiers of early-stage neuron injury in HD. Here, we performed a large-scale RNA interference screen in C. elegans strains that express N-terminal huntingtin (htt) in touch receptor neurons. These neurons control the response to light touch. Their function is strongly impaired by expanded polyglutamines (128Q) as shown by the nearly complete loss of touch response in adult animals, providing an in vivo model in which to manipulate the early phases of expanded-polyQ neurotoxicity. In total, 6034 genes were examined, revealing 662 gene inactivations that either reduce or aggravate defective touch response in 128Q animals. Several genes were previously implicated in HD or neurodegenerative disease, suggesting that this screen has effectively identified candidate targets for HD. Network-based analysis emphasized a subset of high-confidence modifier genes in pathways of interest in HD including metabolic, neurodevelopmental and pro-survival pathways. Finally, 49 modifiers of 128Q-neuron dysfunction that are dysregulated in the striatum of either R/2 or CHL2 HD mice, or both, were identified. Collectively, these results highlight the relevance to HD pathogenesis, providing novel information on the potential therapeutic targets for neuroprotection in HD. © 2012 Lejeune et al; licensee BioMed Central Ltd.

Disinformative data in large-scale hydrological modelling

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A. Kauffeldt

2013-07-01

Full Text Available Large-scale hydrological modelling has become an important tool for the study of global and regional water resources, climate impacts, and water-resources management. However, modelling efforts over large spatial domains are fraught with problems of data scarcity, uncertainties and inconsistencies between model forcing and evaluation data. Model-independent methods to screen and analyse data for such problems are needed. This study aimed at identifying data inconsistencies in global datasets using a pre-modelling analysis, inconsistencies that can be disinformative for subsequent modelling. The consistency between (i basin areas for different hydrographic datasets, and (ii between climate data (precipitation and potential evaporation and discharge data, was examined in terms of how well basin areas were represented in the flow networks and the possibility of water-balance closure. It was found that (i most basins could be well represented in both gridded basin delineations and polygon-based ones, but some basins exhibited large area discrepancies between flow-network datasets and archived basin areas, (ii basins exhibiting too-high runoff coefficients were abundant in areas where precipitation data were likely affected by snow undercatch, and (iii the occurrence of basins exhibiting losses exceeding the potential-evaporation limit was strongly dependent on the potential-evaporation data, both in terms of numbers and geographical distribution. Some inconsistencies may be resolved by considering sub-grid variability in climate data, surface-dependent potential-evaporation estimates, etc., but further studies are needed to determine the reasons for the inconsistencies found. Our results emphasise the need for pre-modelling data analysis to identify dataset inconsistencies as an important first step in any large-scale study. Applying data-screening methods before modelling should also increase our chances to draw robust conclusions from subsequent

Effects of repeated mammographic screening on breast cancer stage distribution

International Nuclear Information System (INIS)

Fagerberg, G.; Baldetorp, L.; Groentoft, O.; Lundstroem, B.; Maanson, J.C.; Nordenskjoeld, B.

1985-01-01

A randomised controlled trial of mass screening for breast cancer by single-view mammography was begun in Sweden in 1977. All women aged 40 and older and resident in the counties of Koppaberg and Oestergoetland were enrolled. The present report is confined to the Oestergoetland study, which started in 1978 and comprised 92934 women. After randomisation, which was done on the basis of communities rather than individuals, 47001 women were allocated to the study group and offered repeated mammographic screening; 45933 were allocated to the control group. As compliance among women over 74 years of age was poor these were excluded from the present report. The yearly incidence of stage II or more advanced breast cancers after the initial screening round up to and including the second was reduced by 40 per cent in the study group compared with the controls. This effect was less marked in the age group 40-49. After 5.5 years average from the date of entry the absolute number of women with stage II-IV disease in the control group exceeded that for the study group by 44, whereas there was a large excess of cancer in situ and stage I cancer in the study group. (orig.)

Does population screening for Chlamydia trachomatis raise anxiety among those tested? Findings from a population based chlamydia screening study.

Science.gov (United States)

Campbell, Rona; Mills, Nicola; Sanford, Emma; Graham, Anna; Low, Nicola; Peters, Tim J

2006-04-25

The advent of urine testing for Chlamydia trachomatis has raised the possibility of large-scale screening for this sexually transmitted infection, which is now the most common in the United Kingdom. The purpose of this study was to investigate the effect of an invitation to be screened for chlamydia and of receiving a negative result on levels of anxiety, depression and self-esteem. 19,773 men and women aged 16 to 39 years, selected at random from 27 general practices in two large city areas (Bristol and Birmingham) were invited by post to send home-collected urine samples or vulvo-vaginal swabs for chlamydia testing. Questionnaires enquiring about anxiety, depression and self-esteem were sent to random samples of those offered screening: one month before the dispatch of invitations; when participants returned samples; and after receiving a negative result. Home screening was associated with an overall reduction in anxiety scores. An invitation to participate did not increase anxiety levels. Anxiety scores in men were lower after receiving the invitation than at baseline. Amongst women anxiety was reduced after receipt of negative test results. Neither depression nor self-esteem scores were affected by screening. Postal screening for chlamydia does not appear to have a negative impact on overall psychological well-being and can lead to a decrease in anxiety levels among respondents. There is, however, a clear difference between men and women in when this reduction occurs.

Does population screening for Chlamydia trachomatis raise anxiety among those tested? Findings from a population based chlamydia screening study

Directory of Open Access Journals (Sweden)

Low Nicola

2006-04-01

Full Text Available Abstract Background The advent of urine testing for Chlamydia trachomatis has raised the possibility of large-scale screening for this sexually transmitted infection, which is now the most common in the United Kingdom. The purpose of this study was to investigate the effect of an invitation to be screened for chlamydia and of receiving a negative result on levels of anxiety, depression and self-esteem. Methods 19,773 men and women aged 16 to 39 years, selected at random from 27 general practices in two large city areas (Bristol and Birmingham were invited by post to send home-collected urine samples or vulvo-vaginal swabs for chlamydia testing. Questionnaires enquiring about anxiety, depression and self-esteem were sent to random samples of those offered screening: one month before the dispatch of invitations; when participants returned samples; and after receiving a negative result. Results Home screening was associated with an overall reduction in anxiety scores. An invitation to participate did not increase anxiety levels. Anxiety scores in men were lower after receiving the invitation than at baseline. Amongst women anxiety was reduced after receipt of negative test results. Neither depression nor self-esteem scores were affected by screening. Conclusion Postal screening for chlamydia does not appear to have a negative impact on overall psychological well-being and can lead to a decrease in anxiety levels among respondents. There is, however, a clear difference between men and women in when this reduction occurs.

Early Dementia Screening

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Peter K. Panegyres

2016-01-01

Full Text Available As the population of the world increases, there will be larger numbers of people with dementia and an emerging need for prompt diagnosis and treatment. Early dementia screening is the process by which a patient who might be in the prodromal phases of a dementing illness is determined as having, or not having, the hallmarks of a neurodegenerative condition. The concepts of mild cognitive impairment, or mild neurocognitive disorder, are useful in analyzing the patient in the prodromal phase of a dementing disease; however, the transformation to dementia may be as low as 10% per annum. The search for early dementia requires a comprehensive clinical evaluation, cognitive assessment, determination of functional status, corroborative history and imaging (including MRI, FDG-PET and maybe amyloid PET, cerebrospinal fluid (CSF examination assaying Aβ1–42, T-τ and P-τ might also be helpful. Primary care physicians are fundamental in the screening process and are vital in initiating specialist investigation and treatment. Early dementia screening is especially important in an age where there is a search for disease modifying therapies, where there is mounting evidence that treatment, if given early, might influence the natural history—hence the need for cost-effective screening measures for early dementia.

Large-scale generation of human iPSC-derived neural stem cells/early neural progenitor cells and their neuronal differentiation.

Science.gov (United States)

D'Aiuto, Leonardo; Zhi, Yun; Kumar Das, Dhanjit; Wilcox, Madeleine R; Johnson, Jon W; McClain, Lora; MacDonald, Matthew L; Di Maio, Roberto; Schurdak, Mark E; Piazza, Paolo; Viggiano, Luigi; Sweet, Robert; Kinchington, Paul R; Bhattacharjee, Ayantika G; Yolken, Robert; Nimgaonka, Vishwajit L; Nimgaonkar, Vishwajit L

2014-01-01

Induced pluripotent stem cell (iPSC)-based technologies offer an unprecedented opportunity to perform high-throughput screening of novel drugs for neurological and neurodegenerative diseases. Such screenings require a robust and scalable method for generating large numbers of mature, differentiated neuronal cells. Currently available methods based on differentiation of embryoid bodies (EBs) or directed differentiation of adherent culture systems are either expensive or are not scalable. We developed a protocol for large-scale generation of neuronal stem cells (NSCs)/early neural progenitor cells (eNPCs) and their differentiation into neurons. Our scalable protocol allows robust and cost-effective generation of NSCs/eNPCs from iPSCs. Following culture in neurobasal medium supplemented with B27 and BDNF, NSCs/eNPCs differentiate predominantly into vesicular glutamate transporter 1 (VGLUT1) positive neurons. Targeted mass spectrometry analysis demonstrates that iPSC-derived neurons express ligand-gated channels and other synaptic proteins and whole-cell patch-clamp experiments indicate that these channels are functional. The robust and cost-effective differentiation protocol described here for large-scale generation of NSCs/eNPCs and their differentiation into neurons paves the way for automated high-throughput screening of drugs for neurological and neurodegenerative diseases.

Impact factors for Reggeon-gluon transition in N=4 SYM with large number of colours

Energy Technology Data Exchange (ETDEWEB)

Fadin, V.S., E-mail: fadin@inp.nsk.su [Budker Institute of Nuclear Physics of SD RAS, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 630090 Novosibirsk (Russian Federation); Fiore, R., E-mail: roberto.fiore@cs.infn.it [Dipartimento di Fisica, Università della Calabria, and Istituto Nazionale di Fisica Nucleare, Gruppo collegato di Cosenza, Arcavacata di Rende, I-87036 Cosenza (Italy)

2014-06-27

We calculate impact factors for Reggeon-gluon transition in supersymmetric Yang–Mills theory with four supercharges at large number of colours N{sub c}. In the next-to-leading order impact factors are not uniquely defined and must accord with BFKL kernels and energy scales. We obtain the impact factor corresponding to the kernel and the energy evolution parameter, which is invariant under Möbius transformation in momentum space, and show that it is also Möbius invariant up to terms taken into account in the BDS ansatz.

Cost Effectiveness of Screening Patients With Gastroesophageal Reflux Disease for Barrett's Esophagus With a Minimally Invasive Cell Sampling Device.

Science.gov (United States)

Heberle, Curtis R; Omidvari, Amir-Houshang; Ali, Ayman; Kroep, Sonja; Kong, Chung Yin; Inadomi, John M; Rubenstein, Joel H; Tramontano, Angela C; Dowling, Emily C; Hazelton, William D; Luebeck, E Georg; Lansdorp-Vogelaar, Iris; Hur, Chin

2017-09-01

It is important to identify patients with Barrett's esophagus (BE), the precursor to esophageal adenocarcinoma (EAC). Patients with BE usually are identified by endoscopy, which is expensive. The Cytosponge, which collects tissue from the esophagus noninvasively, could be a cost-effective tool for screening individuals with gastroesophageal reflux disease (GERD) who are at increased risk for BE. We developed a model to analyze the cost effectiveness of using the Cytosponge in first-line screening of patients with GERD for BE with endoscopic confirmation, compared with endoscopy screening only. We incorporated data from a large clinical trial of Cytosponge performance into 2 validated microsimulation models of EAC progression (the esophageal adenocarcinoma model from Massachusetts General Hospital and the microsimulation screening analysis model from Erasmus University Medical Center). The models were calibrated for US Surveillance, Epidemiology and End Results data on EAC incidence and mortality. In each model, we simulated the effect of a 1-time screen for BE in male patients with GERD, 60 years of age, using endoscopy alone or Cytosponge collection of tissue, and analysis for the level of trefoil factor 3 with endoscopic confirmation of positive results. For each strategy we recorded the number of cases of EAC that developed, the number of EAC cases detected with screening by Cytosponge only or by subsequent targeted surveillance, and the number of endoscopies needed. In addition, we recorded the cumulative costs (including indirect costs) incurred and quality-adjusted years of life lived within each strategy, discounted at a rate of 3% per year, and computed incremental cost-effectiveness ratios (ICERs) among the 3 strategies. According to the models, screening patients with GERD by Cytosponge with follow-up confirmation of positive results by endoscopy would reduce the cost of screening by 27% to 29% compared with screening by endoscopy, but led to 1.8 to 5

The benefits and harms of screening for cancer with a focus on breast screening

DEFF Research Database (Denmark)

Brodersen, John; Juhl Jørgensen, Karsten; Gøtzsche, Peter C.

2010-01-01

. The effects of routine clinical breast examination are unknown, but considering the results of the breast self-examination trials, it is likely that it is harmful. The effects of screening for breast cancer with thermography, ultrasound or magnetic resonance imaging are unknown. It is not clear whether......The balance between benefits and harms is delicate for cancer screening programs. By attending screening with mammography some women will avoid dying from breast cancer or receive less aggressive treatment. But many more women will be overdiagnosed, receive needless treatment, have a false...... and will be treated unnecessarily. Furthermore, more than 200 women will experience substantial psychosocial distress for months because of false-positive findings. Regular breast self-examination does not reduce breast cancer mortality, but doubles the number of biopsies, and it therefore cannot be recommended...

Slepian simulation of distributions of plastic displacements of earthquake excited shear frames with a large number of stories

DEFF Research Database (Denmark)

Lazarov, Boyan Stefanov; Ditlevsen, Ove

2005-01-01

The object of study is a stationary Gaussian white noise excited plane multistory shear frame with a large number of rigid traverses. All the traverse-connecting columns have finite symmetrical yield limits except the columns in one or more of the bottom floors. The columns behave linearly elasti...

Risk stratification and rapid geriatric screening in an emergency department - a quasi-randomised controlled trial.

Science.gov (United States)

Foo, Chik Loon; Siu, Vivan Wing Yin; Ang, Hou; Phuah, Madeline Wei Ling; Ooi, Chee Kheong

2014-08-30

To determine if risk stratification followed by rapid geriatric screening in an emergency department (ED) reduced functional decline, ED reattendance and hospitalisation. This was a quasi-randomised controlled trial. Patients were randomised by the last digit of their national registration identity card (NRIC). Odd number controls received standard ED care; even number patients received geriatric screening, followed by intervention and/or onward referrals. Patients were followed up for 12 months. There were 500 and 280 patients in the control and intervention groups. The intervention group had higher Triage Risk Screening Tool (TRST) scores (34.3% vs 25.4% TRST ≥3, p = 0.01) and lower baseline Instrumental Activity of Daily Living (IADL) scores (22.84 vs 24.18, p fall risk (65.0%), vision (61.4%), and footwear (58.2%). 28.2% were referred to a geriatric clinic and 11.8% were admitted. 425 (85.0%) controls and 234 (83.6%) in the intervention group completed their follow-up. After adjusting for TRST and baseline IADL, the intervention group had significant preservation in function (Basic ADL -0.99 vs -0.24, p geriatric screening at the request of the ED doctor. A major limitation was that a large proportion of patients who were randomized to the intervention group either refused (18.8%) or left the ED before being approached (32.0%). These two groups were not followed up, and hence were excluded in our analysis. Risk stratification and focused geriatric screening in ED resulted in significant preservation of patients' function at 12 months. National Healthcare Group (NHG) Domain Specific Review Board (DSRB) C/09/023. Registered 5th March 2009.

Space Situational Awareness of Large Numbers of Payloads From a Single Deployment

Science.gov (United States)

Segerman, A.; Byers, J.; Emmert, J.; Nicholas, A.

2014-09-01

The nearly simultaneous deployment of a large number of payloads from a single vehicle presents a new challenge for space object catalog maintenance and space situational awareness (SSA). Following two cubesat deployments last November, it took five weeks to catalog the resulting 64 orbits. The upcoming Kicksat mission will present an even greater SSA challenge, with its deployment of 128 chip-sized picosats. Although all of these deployments are in short-lived orbits, future deployments will inevitably occur at higher altitudes, with a longer term threat of collision with active spacecraft. With such deployments, individual scientific payload operators require rapid precise knowledge of their satellites' locations. Following the first November launch, the cataloguing did not initially associate a payload with each orbit, leaving this to the satellite operators. For short duration missions, the time required to identify an experiment's specific orbit may easily be a large fraction of the spacecraft's lifetime. For a Kicksat-type deployment, present tracking cannot collect enough observations to catalog each small object. The current approach is to treat the chip cloud as a single catalog object. However, the cloud dissipates into multiple subclouds and, ultimately, tiny groups of untrackable chips. One response to this challenge may be to mandate installation of a transponder on each spacecraft. Directional transponder transmission detections could be used as angle observations for orbit cataloguing. Of course, such an approach would only be employable with cooperative spacecraft. In other cases, a probabilistic association approach may be useful, with the goal being to establish the probability of an element being at a given point in space. This would permit more reliable assessment of the probability of collision of active spacecraft with any cloud element. This paper surveys the cataloguing challenges presented by large scale deployments of small spacecraft

Screening important inputs in models with strong interaction properties

International Nuclear Information System (INIS)

Saltelli, Andrea; Campolongo, Francesca; Cariboni, Jessica

2009-01-01

We introduce a new method for screening inputs in mathematical or computational models with large numbers of inputs. The method proposed here represents an improvement over the best available practice for this setting when dealing with models having strong interaction effects. When the sample size is sufficiently high the same design can also be used to obtain accurate quantitative estimates of the variance-based sensitivity measures: the same simulations can be used to obtain estimates of the variance-based measures according to the Sobol' and the Jansen formulas. Results demonstrate that Sobol' is more efficient for the computation of the first-order indices, while Jansen performs better for the computation of the total indices.

Screening important inputs in models with strong interaction properties

Energy Technology Data Exchange (ETDEWEB)

Saltelli, Andrea [European Commission, Joint Research Centre, 21020 Ispra, Varese (Italy); Campolongo, Francesca [European Commission, Joint Research Centre, 21020 Ispra, Varese (Italy)], E-mail: francesca.campolongo@jrc.it; Cariboni, Jessica [European Commission, Joint Research Centre, 21020 Ispra, Varese (Italy)

2009-07-15

We introduce a new method for screening inputs in mathematical or computational models with large numbers of inputs. The method proposed here represents an improvement over the best available practice for this setting when dealing with models having strong interaction effects. When the sample size is sufficiently high the same design can also be used to obtain accurate quantitative estimates of the variance-based sensitivity measures: the same simulations can be used to obtain estimates of the variance-based measures according to the Sobol' and the Jansen formulas. Results demonstrate that Sobol' is more efficient for the computation of the first-order indices, while Jansen performs better for the computation of the total indices.

Label free fragment screening using surface plasmon resonance as a tool for fragment finding - analyzing parkin, a difficult CNS target.

Directory of Open Access Journals (Sweden)

Karin Regnström

Full Text Available Surface Plasmon Resonance (SPR is rarely used as a primary High-throughput Screening (HTS tool in fragment-based approaches. With SPR instruments becoming increasingly high-throughput it is now possible to use SPR as a primary tool for fragment finding. SPR becomes, therefore, a valuable tool in the screening of difficult targets such as the ubiquitin E3 ligase Parkin. As a prerequisite for the screen, a large number of SPR tests were performed to characterize and validate the active form of Parkin. A set of compounds was designed and used to define optimal SPR assay conditions for this fragment screen. Using these conditions, more than 5000 pre-selected fragments from our in-house library were screened for binding to Parkin. Additionally, all fragments were simultaneously screened for binding to two off target proteins to exclude promiscuous binding compounds. A low hit rate was observed that is in line with hit rates usually obtained by other HTS screening assays. All hits were further tested in dose responses on the target protein by SPR for confirmation before channeling the hits into Nuclear Magnetic Resonance (NMR and other hit-confirmation assays.

Precise large deviations of aggregate claims in a size-dependent renewal risk model with stopping time claim-number process

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Shuo Zhang

2017-04-01

Full Text Available Abstract In this paper, we consider a size-dependent renewal risk model with stopping time claim-number process. In this model, we do not make any assumption on the dependence structure of claim sizes and inter-arrival times. We study large deviations of the aggregate amount of claims. For the subexponential heavy-tailed case, we obtain a precise large-deviation formula; our method substantially relies on a martingale for the structure of our models.

The WISDOM Study: breaking the deadlock in the breast cancer screening debate.

Science.gov (United States)

Esserman, Laura J

2017-01-01

There are few medical issues that have generated as much controversy as screening for breast cancer. In science, controversy often stimulates innovation; however, the intensely divisive debate over mammographic screening has had the opposite effect and has stifled progress. The same two questions-whether it is better to screen annually or bi-annually, and whether women are best served by beginning screening at 40 or some later age-have been debated for 20 years, based on data generated three to four decades ago. The controversy has continued largely because our current approach to screening assumes all women have the same risk for the same type of breast cancer. In fact, we now know that cancers vary tremendously in terms of timing of onset, rate of growth, and probability of metastasis. In an era of personalized medicine, we have the opportunity to investigate tailored screening based on a woman's specific risk for a specific tumor type, generating new data that can inform best practices rather than to continue the rancorous debate. It is time to move from debate to wisdom by asking new questions and generating new knowledge. The WISDOM Study (Women Informed to Screen Depending On Measures of risk) is a pragmatic, adaptive, randomized clinical trial comparing a comprehensive risk-based, or personalized approach to traditional annual breast cancer screening. The multicenter trial will enroll 100,000 women, powered for a primary endpoint of non-inferiority with respect to the number of late stage cancers detected. The trial will determine whether screening based on personalized risk is as safe, less morbid, preferred by women, will facilitate prevention for those most likely to benefit, and adapt as we learn who is at risk for what kind of cancer. Funded by the Patient Centered Outcomes Research Institute, WISDOM is the product of a multi-year stakeholder engagement process that has brought together consumers, advocates, primary care physicians, specialists, policy

Confocal nanoscanning, bead picking (CONA): PickoScreen microscopes for automated and quantitative screening of one-bead one-compound libraries.

Science.gov (United States)

Hintersteiner, Martin; Buehler, Christof; Uhl, Volker; Schmied, Mario; Müller, Jürgen; Kottig, Karsten; Auer, Manfred

2009-01-01

Solid phase combinatorial chemistry provides fast and cost-effective access to large bead based libraries with compound numbers easily exceeding tens of thousands of compounds. Incubating one-bead one-compound library beads with fluorescently labeled target proteins and identifying and isolating the beads which contain a bound target protein, potentially represents one of the most powerful generic primary high throughput screening formats. On-bead screening (OBS) based on this detection principle can be carried out with limited automation. Often hit bead detection, i.e. recognizing beads with a fluorescently labeled protein bound to the compound on the bead, relies on eye-inspection under a wide-field microscope. Using low resolution detection techniques, the identification of hit beads and their ranking is limited by a low fluorescence signal intensity and varying levels of the library beads' autofluorescence. To exploit the full potential of an OBS process, reliable methods for both automated quantitative detection of hit beads and their subsequent isolation are needed. In a joint collaborative effort with Evotec Technologies (now Perkin-Elmer Cellular Technologies Germany GmbH), we have built two confocal bead scanner and picker platforms PS02 and a high-speed variant PS04 dedicated to automated high resolution OBS. The PS0X instruments combine fully automated confocal large area scanning of a bead monolayer at the bottom of standard MTP plates with semiautomated isolation of individual hit beads via hydraulic-driven picker capillaries. The quantification of fluorescence intensities with high spatial resolution in the equatorial plane of each bead allows for a reliable discrimination between entirely bright autofluorescent beads and real hit beads which exhibit an increased fluorescence signal at the outer few micrometers of the bead. The achieved screening speed of up to 200,000 bead assayed in less than 7 h and the picking time of approximately 1 bead

Cancer screening in patients infected with HIV.

Science.gov (United States)

Sigel, Keith; Dubrow, Robert; Silverberg, Michael; Crothers, Kristina; Braithwaite, Scott; Justice, Amy

2011-09-01

Non-AIDS-defining cancers are a rising health concern among HIV-infected patients. Cancer screening is now an important component of health maintenance in HIV clinical practice. The decision to screen an HIV-infected patient for cancer should include an assessment of individualized risk for the particular cancer, life expectancy, and the harms and benefits associated with the screening test and its potential outcome. HIV-infected patients are at enhanced risk of several cancers compared to the general population; anal cancer, hepatocellular carcinoma, Hodgkin's lymphoma, and lung cancer all have good evidence demonstrating an enhanced risk in HIV-infected persons. A number of cancer screening interventions have shown benefit for specific cancers in the general population, but data on the application of these tests to HIV-infected persons are limited. Here we review the epidemiology and background literature relating to cancer screening interventions in HIV-infected persons. We then use these data to inform a conceptual model for evaluating HIV-infected patients for cancer screening.

THE DEVELOPMENT OF SCREEN TRANSLATION

Directory of Open Access Journals (Sweden)

Sang Ayu Isnu Maharani

2014-05-01

Full Text Available Screen translations involve oral translation known as dubbing and revoicing. Re-voicing consists of lip-sync dubbing, free commentary, narration and voice over. The written version is called subtitle. Dubbing and subtitling are two preferred mode used in the screen translation even though various numbers of current options are available nowadays. Dubbing commenced to be used in larger countries in Europe meanwhile smaller countries apply subtitling because it is more economical than dubbing. In Indonesia, the use of dubbing as well as subtitle are found.

Screening from the epidemiological point of view

International Nuclear Information System (INIS)

Becker, N.

2002-01-01

The scope of screening is to identify disease in a clinically inapparent stage in order to treat more effectively. However, the required application of a test to large subsets of the population implies risks which cannot be ignored. Thus, the introduction of a test for use in screening without previously established evidence of a benefit which exceeds potential harm by far cannot be justified. With regard to cancer, evidence of effectiveness has been proven for screening on cervical (Papsmear), breast (mammography) and colorectal (faecal occult blood test) cancer. The routine application of a screening procedure which has been proven effective provides the benefit in terms of mortality reduction seen in the trials only if the entire screening chain, from the test over potentially required assessment to treatment, is offered with highest quality and is under permanent quality control. (orig.) [de

Screening for congenital hypothyroidism (CH) among Filipino newborn infants. Philippine Newborn Screening Study Group.

Science.gov (United States)

Fagela-Domingo, C; Padilla, C D; Cutiongco, E M

1999-01-01

From June 1996 to June 1998 a total of 62.841 newborn infants were screened for congenital hypothyroidism with thyroid stimulating hormone assay as a primary test. The method used was an immunofluorescent assay using the DELFIA TSH Kit on dried blood specimens collected by heelprick on filter paper. All infants with TSH values greater than 20 microU/ml were retested. If the results remained abnormally high, confirmatory testing was done by radioimmunoassay. All infants who were confirmed to be hypothyroid were referred to pediatric endocrinologists for initial management. The overall weighted incidence of congenital hypothyroidism obtained in this study was 0.000277 (95% CI; 0.000122 - 0.000432) or 1:3,610 which may be higher than that reported by most screening programs worldwide. The recall rate was 0.16%. The higher recall rate may be explained by early testing in a number of cases and by the possibility of iodine deficiency in some of the mothers. On the basis of the results of this study, we would recommend (1) screening on a greater number of infants to verify the incidence of CH and (2) establishing normal TSH values at different hours of life to improve our recall rate.

Adenoma detection in patients undergoing a comprehensive colonoscopy screening

International Nuclear Information System (INIS)

Raju, Gottumukkala S; Vadyala, Vikram; Slack, Rebecca; Krishna, Somashekar G; Ross, William A; Lynch, Patrick M; Bresalier, Robert S; Hawk, Ernest; Stroehlein, John R

2013-01-01

Measures shown to improve the adenoma detection during colonoscopy (excellent bowel preparation, cecal intubation, cap fitted colonoscope to examine behind folds, patient position change to optimize colon distention, trained endoscopy team focusing on detection of subtle flat lesions, and incorporation of optimum endoscopic examination with adequate withdrawal time) are applicable to clinical practice and, if incorporated are projected to facilitate comprehensive colonoscopy screening program for colon cancer prevention. To determine adenoma and serrated polyp detection rate under conditions designed to optimize quality parameters for comprehensive screening colonoscopy. Retrospective analysis of data obtained from a comprehensive colon cancer screening program designed to optimize quality parameters. Academic medical center. Three hundred and forty-three patients between the ages of 50 years and 75 years who underwent first screening colonoscopy between 2009 and 2011 among 535 consecutive patients undergoing colonoscopy. Comprehensive colonoscopy screening program was utilized to screen all patients. Cecal intubation was successful in 98.8% of patients. The Boston Bowel Preparation Scale for quality of colonoscopy was 8.97 (95% confidence interval [CI]; 8.94, 9.00). The rate of adenoma detection was 60% and serrated lesion (defined as serrated adenomas or hyperplastic polyps proximal to the splenic flexure) detection was 23%. The rate of precancerous lesion detection (adenomas and serrated lesions) was 66%. The mean number of adenomas per screening procedure was 1.4 (1.2, 1.6) and the mean number of precancerous lesions (adenomas or serrated lesions) per screening procedure was 1.6 (1.4, 1.8). Retrospective study and single endoscopist experience. A comprehensive colonoscopy screening program results in high-quality screening with high detection of adenomas, advanced adenomas, serrated adenomas, and multiple adenomas

Metabolic screening in patients with polycystic ovary syndrome is largely underutilized among obstetrician-gynecologists.

Science.gov (United States)

Dhesi, Amy S; Murtough, Katie L; Lim, Jonathan K; Schulkin, Jay; McGovern, Peter G; Power, Michael L; Morelli, Sara S

2016-11-01

Women with polycystic ovary syndrome have substantially higher rates of insulin resistance, impaired glucose tolerance, type 2 diabetes, dyslipidemia, and metabolic syndrome when compared with women without the disease. Given the high prevalence of these comorbidities, guidelines issued by the American College of Obstetricians and Gynecologists and the Endocrine Society recommend that all women with polycystic ovary syndrome undergo screening for impaired glucose tolerance and dyslipidemia with a 2 hour 75 g oral glucose tolerance test and fasting lipid profile upon diagnosis and also undergo repeat screening every 2-5 years and every 2 years, respectively. Although a hemoglobin A1C and/or fasting glucose are widely used screening tests for diabetes, both the American College of Obstetricians and Gynecologists and the Endocrine Society preferentially recommend the 2 hour oral glucose tolerance test in women with polycystic ovary syndrome as a superior indicator of impaired glucose tolerance/diabetes mellitus. However, we found that gynecologists underutilize current recommendations for metabolic screening in women with polycystic ovary syndrome. In an online survey study targeting American College of Obstetricians and Gynecologists fellows and junior fellows, 22.3% of respondents would not order any screening test at the initial visit for at least 50% of their patients with polycystic ovary syndrome. The most common tests used to screen for impaired glucose tolerance in women with polycystic ovary syndrome were hemoglobin A1C (51.0%) and fasting glucose (42.7%). Whereas 54.1% would order a fasting lipid profile in at least 50% of their polycystic ovary syndrome patients, only 7% of respondents order a 2 hour oral glucose tolerance test. We therefore call for increased efforts to encourage obstetrician-gynecologists to address metabolic abnormalities in their patients with polycystic ovary syndrome. Such efforts should include education of physicians early in their

Use of ultra-high pressure liquid chromatography coupled to high resolution mass spectrometry for fast screening in high throughput doping control.

Science.gov (United States)

Musenga, Alessandro; Cowan, David A

2013-05-03

We describe a sensitive, comprehensive and fast screening method based on liquid chromatography-high resolution mass spectrometry for the detection of a large number of analytes in sports samples. UHPLC coupled to high resolution mass spectrometry with polarity switching capability is applied for the rapid screening of a large number of analytes in human urine samples. Full scan data are acquired alternating both positive and negative ionisation. Collision-induced dissociation with positive ionisation is also performed to produce fragment ions to improve selectivity for some analytes. Data are reviewed as extracted ion chromatograms based on narrow mass/charge windows (±5ppm). A simple sample preparation method was developed, using direct enzymatic hydrolysis of glucuronide conjugates, followed by solid phase extraction with mixed mode ion-exchange cartridges. Within a 10min run time (including re-equilibration) the method presented allows for the analysis of a large number of analytes from most of the classes in the World Anti-Doping Agency (WADA) Prohibited List, including anabolic agents, β2-agonists, hormone antagonists and modulators, diuretics, stimulants, narcotics, glucocorticoids and β-blockers, and does so while meeting the WADA sensitivity requirements. The high throughput of the method and the fast sample pre-treatment reduces analysis cost and increases productivity. The method presented has been used for the analysis of over 5000 samples in about one month and proved to be reliable. Copyright © 2013 Elsevier B.V. All rights reserved.

Risk of cancer radioinduced by mammographic screening

International Nuclear Information System (INIS)

Correa, Rosangela da Silveira; Peixoto, Joao Emilio; Ferreira, Rubemar de Souza; Freitas-Junior, Ruffo

2013-01-01

This work aims to estimate the risk benefit of mammography, in terms of the number of lives saved/number of lives lost, in the female population of the State of Goias, Brazil, depending on the age range indicated for screening and the type of technology available

The effectiveness and cost-effectiveness of screening for active tuberculosis among migrants in the EU/EEA: a systematic review

Science.gov (United States)

Greenaway, Christina; Pareek, Manish; Abou Chakra, Claire-Nour; Walji, Moneeza; Makarenko, Iuliia; Alabdulkarim, Balqis; Hogan, Catherine; McConnell, Ted; Scarfo, Brittany; Christensen, Robin; Tran, Anh; Rowbotham, Nick; Noori, Teymur; van der Werf, Marieke J; Pottie, Kevin; Matteelli, Alberto; Zenner, Dominik; Morton, Rachael L

2018-01-01

Background : The foreign-born population make up an increasing and large proportion of tuberculosis (TB) cases in European Union/European Economic Area (EU/EEA) low-incidence countries and challenge TB elimination efforts. Methods : We conducted a systematic review to determine effectiveness (yield and performance of chest radiography (CXR) to detect active TB, treatment outcomes and acceptance of screening) and a second systematic review on cost-effectiveness of screening for active TB among migrants living in the EU/EEA. Results : We identified six systematic reviews, one report and three individual studies that addressed our aims. CXR was highly sensitive (98%) but only moderately specific (75%). The yield of detecting active TB with CXR screening among migrants was 350 per 100,000 population overall but ranged widely by host country (110–2,340), migrant type (170–1,192), TB incidence in source country (19–336) and screening setting (220–1,720). The CXR yield was lower (19.6 vs 336/100,000) and the numbers needed to screen were higher (5,076 vs 298) among migrants from source countries with lower TB incidence (≤ 50 compared with ≥ 350/100,000). Cost-effectiveness was highest among migrants originating from high (> 120/100,000) TB incidence countries. The foreign-born had similar or better TB treatment outcomes than those born in the EU/EEA. Acceptance of CXR screening was high (85%) among migrants. Discussion: Screening programmes for active TB are most efficient when targeting migrants from higher TB incidence countries. The limited number of studies identified and the heterogeneous evidence highlight the need for further data to inform screening programmes for migrants in the EU/EEA. PMID:29637888

Prevalence of HIV positive blood donors among screened ...

African Journals Online (AJOL)

Two thousand five hundred and thirty two (2,532) males, aged 25 – 50 years potential blood donors were randomly selected from the total number of volunteer blood donors who satisfied the initial screening criteria for donating blood, and were screened for HIV using Immunocomb II (HIV 1 and 2 Bispot) and Recombigen ...

Cervical cancer screening policies and coverage in Europe

DEFF Research Database (Denmark)

Anttila, Ahti; von Karsa, Lawrence; Aasmaa, Auni

2009-01-01

with education, training and communication among women, medical professionals and authorities are required, accordingly. The study indicates that, despite substantial efforts, the recommendations of the Council of the EU on organised population-based screening for cervical cancer are not yet fulfilled. Decision......The aim of the study was to compare current policy, organisation and coverage of cervical cancer screening programmes in the European Union (EU) member states with European and other international recommendations. According to the questionnaire-based survey, there are large variations in cervical...... cancer screening policies and inadequacies in the key organisational elements of the programme such as registration and monitoring required for quality-assurance and fail-safe mechanisms. Based on data from available screening registers, coverage of the screening test taken within the population...

Vortex Ring Interaction with a Heated Screen

Science.gov (United States)

Smith, Jason; Krueger, Paul S.

2008-11-01

Previous examinations of vortex rings impinging on porous screens has shown the reformation of the vortex ring with a lower velocity after passing through the screen, the creation of secondary vortices, and mixing. A heated screen could, in principle, alter the vortex-screen interaction by changing the local liquid viscosity and density. In the present investigation, a mechanical piston-cylinder vortex ring generator was used to create vortex rings in an aqueous sucrose solution. The rings impinged on a screen of horizontal wires that were heated using electrical current. The flow was visualized with food color and video imaging. Tests with and without heat were conducted at a piston stroke-to-jet diameter ratio of 4 and a jet Reynolds number (Re) of 1000. The vortex rings slowed after passing through the screen, but in tests with heat, they maintained a higher fraction of their before-screen velocity due to reduction in fluid viscosity near the wires. In addition, small ``fingers'' that developed on the front of the vortex rings as they passed through the screen exhibited positive buoyancy effects in the heated case.

Need for and relevance of prostate cancer screening in Nigeria.

Science.gov (United States)

Akinremi, To; Adeniyi, A; Olutunde, A; Oduniyi, A; Ogo, Cn

2014-01-01

Prostate cancer (PCa) has become the most prevalent cancer among males in Nigeria, and similar to other black populations, Nigerian men present with more advanced disease at an earlier age than in several other ethnic groups. In this unscreened, high-risk group, the reference range for early detection and diagnosis as well as risk factors need to be determined through large-scale screening. Over 4 years, 1124 previously unscreened men between 40 and 85 years of age were screened at free community health programmes for PCa, using the common parameters of prostate-specific antigen (PSA) plus digital rectal examination (DRE). We thereby assessed the practicality and importance of screening. Consent was obtained, demographic data obtained, PSA measured using qualitative laboratory kits, and DRE performed by surgeons. We found that the number of men attending and consenting to screening increases from year to year. Of 40-85-year-old men, 85.4% consented, of whom 33.3% (a third) and 60% were 51-60 years old and 51-65 years, respectively. While 11.5% of men had PSA >4 ng/ml, 31.45% showed abnormal DRE. Of the men who took the PSA test, 79.2% also consented to the DRE, of whom 5.8% had combined abnormal DRE and PSA >4 ng/ml. Our findings suggest that Nigerian men are a willing group for screening by both the PSA and DRE with the positive response to calls for health screening and interest in prostate health. The finding of PSA >4 ng/ml in 11.15% of this population reveals the need for greater awareness and measures to increase early detection. However, the value and validity of established PSA reference ranges and cutoff of 'normal' still need to be established. Screening is very important to better define the PCa prevalence and characteristics in our population; otherwise political and economic circumstances will ensure that men still present late with aggressive PCa.

Clinical findings and genetic screening for copy number variation ...

African Journals Online (AJOL)

to the Unified Parkinson's Disease Rating Scale (UPDRS), and patients were classified according to motor features. Genomic DNA was extracted and multiplex ligation-dependent probe amplification was used for detection of copy number variation (CNV) mutations in the known PD-causing genes. Results. Sixteen patients ...

Exploiting biospectroscopy as a novel screening tool for cervical cancer: towards a framework to validate its accuracy in a routine clinical setting.

LENUS (Irish Health Repository)

Purandare, Nikhil C

2013-11-01

Biospectroscopy is an emerging field that harnesses the platform of physical sciences with computational analysis in order to shed novel insights on biological questions. An area where this approach seems to have potential is in screening or diagnostic clinical settings, where there is an urgent need for new approaches to objectively interrogate large numbers of samples in an objective fashion with acceptable levels of sensitivity and specificity. This review outlines the benefits of biospectroscopy in screening for precancer lesions of the cervix due to its ability to separate different grades of dysplasia. It evaluates the feasibility of introducing this technique into cervical screening programs on the basis of its ability to identify biomarkers of progression within derived spectra (\\'biochemical‑cell fingerprints\\').

Hidden costs of low-cost screening mammography

International Nuclear Information System (INIS)

Cyrlak, D.

1987-01-01

Twenty-two hundred women in Orange County, California, took part in a low-cost mammography screening project sponsored by the American Cancer Society and the KCBS-TV. Patients were followed up by telephone and questioned about actual costs incurred as a result of screening mammography, including costs of repeated and follow-up mammograms, US examinations and surgical consultations. The total number of biopsies, cancers found, and the costs involved were investigated. The authors' results suggest that particularly in centers with a high positive call rate, the cost of screening mammograms accounts for only a small proportion of the medical costs

Cervical screening in HPV-vaccinated populations.

Science.gov (United States)

Canfell, K

2018-06-01

Cervical screening with cytology has been the basis for substantial reductions in cervical cancer incidence and mortality in most high-income countries over the last few decades. More recently, there have been two key, parallel developments which have prompted a major re-consideration of cervical screening. The first is the emergence of evidence on the improved sensitivity of human papillomavirus (HPV) DNA testing compared to cytology, and the second is the large-scale deployment of prophylactic vaccination against HPV. A key challenge to be overcome before HPV screening could be introduced into national cervical screening programs was the specificity of an infection, for detection of precancerous lesions. This has been done in three ways: (1) by considering the appropriate age for starting HPV screening (30 years in unvaccinated populations and 25 years in populations with mature vaccination programs and high vaccine uptake) and the appropriate screening interval; (2) via development of clinical HPV tests, which are (by design) not as sensitive to low viral loads; and (3) by introducing effective triaging for HPV-positive women, which further risk-stratifies women before referral for diagnostic evaluation. This review discusses these major developments and describes how the benefits of HPV screening are being optimized in both unvaccinated and vaccinated populations.

Substantial improvements in large-scale redocking and screening using the novel HYDE scoring function

Science.gov (United States)

Schneider, Nadine; Hindle, Sally; Lange, Gudrun; Klein, Robert; Albrecht, Jürgen; Briem, Hans; Beyer, Kristin; Claußen, Holger; Gastreich, Marcus; Lemmen, Christian; Rarey, Matthias

2012-06-01

The HYDE scoring function consistently describes hydrogen bonding, the hydrophobic effect and desolvation. It relies on HYdration and DEsolvation terms which are calibrated using octanol/water partition coefficients of small molecules. We do not use affinity data for calibration, therefore HYDE is generally applicable to all protein targets. HYDE reflects the Gibbs free energy of binding while only considering the essential interactions of protein-ligand complexes. The greatest benefit of HYDE is that it yields a very intuitive atom-based score, which can be mapped onto the ligand and protein atoms. This allows the direct visualization of the score and consequently facilitates analysis of protein-ligand complexes during the lead optimization process. In this study, we validated our new scoring function by applying it in large-scale docking experiments. We could successfully predict the correct binding mode in 93% of complexes in redocking calculations on the Astex diverse set, while our performance in virtual screening experiments using the DUD dataset showed significant enrichment values with a mean AUC of 0.77 across all protein targets with little or no structural defects. As part of these studies, we also carried out a very detailed analysis of the data that revealed interesting pitfalls, which we highlight here and which should be addressed in future benchmark datasets.

Consensus review of discordant findings maximizes cancer detection rate in double-reader screening mammography: Irish National Breast Screening Program experience.

Science.gov (United States)

Shaw, Colette M; Flanagan, Fidema L; Fenlon, Helen M; McNicholas, Michelle M

2009-02-01

To assesses consensus review of discordant screening mammography findings in terms of its sensitivity, safety, and effect on overall performance in the first 6 years of operation of the Irish National Breast Screening Program (NBSP). Women who participated in the Irish NBSP gave written informed consent for use of their data for auditing purposes. Local ethics committee approval was obtained. The study population consisted of women who participated in the Irish NBSP and underwent initial screening mammography at one of the two screening centers serving the eastern part of Ireland between 2000 and 2005. Independent double reading of mammograms was performed. When the readers disagreed regarding referral, the case was reviewed by a consensus panel. Of the 128 569 screenings performed, 1335 (1%) were discussed by consensus. Of the 1335 cases discussed by consensus, 606 (45.39%) were recalled for further assessment. This resulted in an overall recall rate of 4.41%. In those recalled to assessment, 71 cases of malignant disease were diagnosed (ductal carcinoma in situ, n = 24; invasive cancer, n = 47). The remaining 729 patients were returned to biennial screening. Of these 729 patients, seven had false-negative findings that were identified in the subsequent screening round. Use of the highest reader recall method, in which a patient is recalled if her findings are deemed abnormal by either reader, could potentially increase the cancer detection rate by 0.6 per 1000 women screened but would increase the recall rate by 12.69% and the number of false-positive findings by 15.37%. The consensus panel identified 71 (7.33%) of 968 cancers diagnosed. Consensus review substantially reduced the number of cases recalled and was associated with a low false-negative rate.

The longitudinal impact of patient navigation on equity in colorectal cancer screening in a large primary care network.

Science.gov (United States)

Percac-Lima, Sanja; López, Lenny; Ashburner, Jeffrey M; Green, Alexander R; Atlas, Steven J

2014-07-01

The long-term effects of interventions to improve colorectal (CRC) screening in vulnerable populations are uncertain. The authors evaluated the impact of patient navigation (PN) on the equity of CRC prevention over a 5-year period. A culturally tailored CRC screening PN program was implemented in 1 community health center (CHC) in 2007. In a primary care network, CRC screening rates from 2006 to 2010 among eligible patients from the CHC with PN were compared with the rates from other practices without PN. Multivariable logistic regression models for repeated measures were used to assess differences over time. Differences in CRC screening rates diminished among patients at the CHC with PN and at other practices between 2006 (49.2% vs 62.5%, respectively; P practices (5% vs 3.4% per year; P practices, lower CRC screening rates in 2006 (47.5% vs 52.1%, respectively; P = .02) were higher by 2010 (73.5% vs 67.3%, respectively; P practices in 2006 (44.3% vs 44.7%, respectively; P = .79) were higher at the CHC by 2010 (70.6% vs 58.6%, respectively; P practices (both P < .001). A PN program increased CRC screening rates in a CHC and improved equity in vulnerable patients. Long-term funding of PN programs has the potential to reduce cancer screening disparities. © 2014 American Cancer Society.

Cancer screening literature in the period 2000-2002: pointers to future research avenues.

Science.gov (United States)

Moore, Malcolm A; Kunimoto, Takehiko; Tsuda, Hiroyuki

2003-01-01

In order to determine which areas of cancer screening are currently receiving greatest emphasis in different parts of the world a Medline search of the literature for the period 2000-2002 was performed, concentrating attention on research into all aspects of efforts for early detection of tumours, with especial attention to methodology, motivation (including awareness of utility in the general populace and in minority groups), and intervention (professional training and general education). Focus on the skin, lung, cervix, breast, ovary + endometrium, oral cavity-oesophagus, gastric, colorectal, kidney + urinary tract and prostate, demonstrated large numbers of journals to be publishing papers in the field, with 10, 33, 130, 53, 24, 21, 6, 81, 12 and 58, respectively, in the period investigated, the grand total being 259. The average numbers of papers/journal ranged from 1.0-2.4 with only 15-35% appearing in journals with wide coverage. With the exception of oral, oesophageal and gastric cancer screening, an approximately 50% contribution in all areas was made by scientists in the US, followed by Europe (31% overall,) Asia (11%) then Australasia, Central and South America and Africa (3%, 2% and 1%, respectively). Clear differences were evident with the organ regarding specific topics receiving attention, most publications concerning the lung, ovary and urological tract dealing with detection methods. With the cervix and colorectum this topic accounted for half of the papers with especial attention to the relative advantages of the PAP smear, HPV testing and direct visual acetic acid (DVA) in the one, and FOBT and endoscopy in the other. Another major focus was found to be minority attitudes to breast, prostate and cervical screening in the US, whereas only few papers were found dealing with practical intervention, targeting professionals or screenees to increase participation in screening programs. The present approach suggested a number of areas requiring more

TO BE OR NOT TO BE: AN INFORMATIVE NON-SYMBOLIC NUMERICAL MAGNITUDE PROCESSING STUDY ABOUT SMALL VERSUS LARGE NUMBERS IN INFANTS

Directory of Open Access Journals (Sweden)

Annelies CEULEMANS

2014-03-01

Full Text Available Many studies tested the association between numerical magnitude processing and mathematical achievement with conflicting findings reported for individuals with mathematical learning disorders. Some of the inconsistencies might be explained by the number of non-symbolic stimuli or dot collections used in studies. It has been hypothesized that there is an object-file system for ‘small’ and an analogue magnitude system for ‘large’ numbers. This two-system account has been supported by the set size limit of the object-file system (three items. A boundary was defined, accordingly, categorizing numbers below four as ‘small’ and from four and above as ‘large’. However, data on ‘small’ number processing and on the ‘boundary’ between small and large numbers are missing. In this contribution we provide data from infants discriminating between the number sets 4 vs. 8 and 1 vs. 4, both containing the number four combined with a small and a large number respectively. Participants were 25 and 26 full term 9-month-olds for 4 vs. 8 and 1 vs. 4 respectively. The stimuli (dots were controlled for continuous variables. Eye-tracking was combined with the habituation paradigm. The results showed that the infants were successful in discriminating 1 from 4, but failed to discriminate 4 from 8 dots. This finding supports the assumption of the number four as a ‘small’ number and enlarges the object-file system’s limit. This study might help to explain inconsistencies in studies. Moreover, the information may be useful in answering parent’s questions about challenges that vulnerable children with number processing problems, such as children with mathematical learning disorders, might encounter. In addition, the study might give some information on the stimuli that can be used to effectively foster children’s magnitude processing skills.

Supplementary Material for: DRABAL: novel method to mine large high-throughput screening assays using Bayesian active learning

KAUST Repository

Soufan, Othman

2016-01-01

Abstract Background Mining high-throughput screening (HTS) assays is key for enhancing decisions in the area of drug repositioning and drug discovery. However, many challenges are encountered in the process of developing suitable and accurate methods for extracting useful information from these assays. Virtual screening and a wide variety of databases, methods and solutions proposed to-date, did not completely overcome these challenges. This study is based on a multi-label classification (MLC) technique for modeling correlations between several HTS assays, meaning that a single prediction represents a subset of assigned correlated labels instead of one label. Thus, the devised method provides an increased probability for more accurate predictions of compounds that were not tested in particular assays. Results Here we present DRABAL, a novel MLC solution that incorporates structure learning of a Bayesian network as a step to model dependency between the HTS assays. In this study, DRABAL was used to process more than 1.4 million interactions of over 400,000 compounds and analyze the existing relationships between five large HTS assays from the PubChem BioAssay Database. Compared to different MLC methods, DRABAL significantly improves the F1Score by about 22%, on average. We further illustrated usefulness and utility of DRABAL through screening FDA approved drugs and reported ones that have a high probability to interact with several targets, thus enabling drug-multi-target repositioning. Specifically DRABAL suggests the Thiabendazole drug as a common activator of the NCP1 and Rab-9A proteins, both of which are designed to identify treatment modalities for the Niemannâ Pick type C disease. Conclusion We developed a novel MLC solution based on a Bayesian active learning framework to overcome the challenge of lacking fully labeled training data and exploit actual dependencies between the HTS assays. The solution is motivated by the need to model dependencies between

[ASCUS in screening].

Science.gov (United States)

Caprara, L; Monari, F; De Bianchi, P S; Amadori, A; Bondi, A

2001-12-01

The significance and use of the cytological diagnosis "atypical squamous cells of undetermined significance" (ASCUS) remain a major problem in cervical cancer screening. The prevalence of ASCUS by patient age has seldom been investigated. The present paper reports the prevalence of ASCUS in a large series of screening Pap smears from the Italian region of Emilia-Romagna. The study was based on the data collected by the Department of Health of the Emilia-Romagna Region for the first 3-year round (1997-1999) of a population-based screening programme (target age, 25-64 years). The age-specific frequency of ASCUS has been calculated as a prevalence rate per 1000 screened patients. A total of 597,386 women participated in the programme. Women diagnosed with ASCUS (n = 8205 or 13.7 per 1000) accounted for 49% of the recalls for colposcopy (n = 16,871, or 28.2 per 1000). The prevalence of diagnoses of low-grade squamous intraepithelial lesions (LG-SIL) decreased progressively with age while that of high-grade SIL was slightly higher between 30 and 39 years. The prevalence of ASCUS peaked at age 45-49 years (17.3 per 1000 subjects). The observed peak reflects the prevalence of (1) cytological changes closely associated with perimenopausal age and at least compatible with the ASCUS diagnosis, and (2) cytological abnormalities induced by hormone replacement therapy.

A Novel Yeast Surface Display Method for Large-Scale Screen Inhibitors of Sortase A.

Science.gov (United States)

Wu, Lin; Li, Huijun; Tang, Tianle

2017-01-24

high-throughput analysis, but the conventional method is much more sensitive. The method described in this paper is expected to lead to large-scale screening of sortase A inhibitors which can be used to decrease the risk of drug resistance development.

A Novel Yeast Surface Display Method for Large-Scale Screen Inhibitors of Sortase A

Directory of Open Access Journals (Sweden)

Lin Wu

2017-01-01

suitable for high-throughput analysis, but the conventional method is much more sensitive. The method described in this paper is expected to lead to large-scale screening of sortase A inhibitors which can be used to decrease the risk of drug resistance development.

The Feasibility of Tree Coring as a Screening Tool for Selected Contaminants in the Subsurface

DEFF Research Database (Denmark)

Nielsen, Mette Algreen

Chemical release resulting from inadequate care in the handling and storage of compounds has ultimately led to a large number of contaminated sites worldwide. Frequently found contaminants in the terrestrial environment include BTEX (benzene, toluene, ethylbenzene, and xylenes), heavy metals, PAH...... sampling density. This, together with a relatively large soil volume represented by a tree core, has shown to reduce the risk of overlooking contaminated areas and is a valuable method for the identification of previously unknown source areas within a short time period....... (polycyclic aromatic hydrocarbons) and chlorinated solvents. The large number of contaminated sites has created a need for effective and reliable site investigations. In this PhD project the feasibility of tree coring as a screening tool for selected contaminants in the subsurface has been investigated...... to obtain more efficient site investigations. Trees have a natural ability to take up water and nutrients from the subsurface; consequently, contaminants can also enter the roots and be translocated to plant parts above ground where they will be absorbed, degraded or phytovolatilized depending...

Visual analysis of inter-process communication for large-scale parallel computing.

Science.gov (United States)

Muelder, Chris; Gygi, Francois; Ma, Kwan-Liu

2009-01-01

In serial computation, program profiling is often helpful for optimization of key sections of code. When moving to parallel computation, not only does the code execution need to be considered but also communication between the different processes which can induce delays that are detrimental to performance. As the number of processes increases, so does the impact of the communication delays on performance. For large-scale parallel applications, it is critical to understand how the communication impacts performance in order to make the code more efficient. There are several tools available for visualizing program execution and communications on parallel systems. These tools generally provide either views which statistically summarize the entire program execution or process-centric views. However, process-centric visualizations do not scale well as the number of processes gets very large. In particular, the most common representation of parallel processes is a Gantt char t with a row for each process. As the number of processes increases, these charts can become difficult to work with and can even exceed screen resolution. We propose a new visualization approach that affords more scalability and then demonstrate it on systems running with up to 16,384 processes.

Screening for Posttraumatic Stress Disorder among Somali ex-combatants: A validation study

Directory of Open Access Journals (Sweden)

Rockstroh Brigitte

2007-09-01

Full Text Available Abstract Background In Somalia, a large number of active and former combatants are affected by psychological problems such as Posttraumatic Stress Disorder (PTSD. This disorder impairs their ability to re-integrate into civilian life. However, many screening instruments for Posttraumatic Stress Disorder used in post-conflict settings have limited validity. Here we report on development and validation of a screening tool for PTSD in Somali language with a sample of ex-combatants. Methods We adapted the Posttraumatic Diagnostic Scale (PDS to reflect linguistic and cultural differences within the Somali community so that local interviewers could be trained to administer the scale. For validation purposes, a randomly selected group of 135 Somali ex-combatants was screened by trained local interviewers; 64 of them were then re-assessed by trained clinical psychologists using the Composite International Diagnostic Interview (CIDI and the Self-Report Questionnaire (SRQ-20. Results The screening instrument showed good internal consistency (Cronbach's α = .86, convergent validity with the CIDI (sensitivity = .90; specificity = .90 as well as concurrent validity: positive cases showed higher SRQ-20 scores, higher prevalence of psychotic symptoms, and higher levels of intake of the local stimulant drug khat. Compared to a single cut-off score, the multi-criteria scoring, in keeping with the DSM-IV, produced more diagnostic specificity. Conclusion The results provide evidence that our screening instrument is a reliable and valid method to detect PTSD among Somali ex-combatants. A future Disarmament, Demobilization and Reintegration Program in Somalia is recommended to screen for PTSD in order to identify ex-combatants with special psycho-social needs.

Screening and Invasive Testing in Twins

Directory of Open Access Journals (Sweden)

Giovanni Monni

2014-07-01

Full Text Available Prenatal screening and testing for trisomy 21 in twin pregnancies poses a number of challenges: the exact estimate of the a priori risk of trisomy 21, the choice of prenatal screening test and/or invasive techniques to employ for the diagnosis and the impact of the result on the options of treatment in case of discordant results within a twin pair or among multiples. These different aspects are discussed below while recognizing that many issues remain unresolved.

MOLA: a bootable, self-configuring system for virtual screening using AutoDock4/Vina on computer clusters

Directory of Open Access Journals (Sweden)

Abreu Rui MV

2010-10-01

Full Text Available Abstract Background Virtual screening of small molecules using molecular docking has become an important tool in drug discovery. However, large scale virtual screening is time demanding and usually requires dedicated computer clusters. There are a number of software tools that perform virtual screening using AutoDock4 but they require access to dedicated Linux computer clusters. Also no software is available for performing virtual screening with Vina using computer clusters. In this paper we present MOLA, an easy-to-use graphical user interface tool that automates parallel virtual screening using AutoDock4 and/or Vina in bootable non-dedicated computer clusters. Implementation MOLA automates several tasks including: ligand preparation, parallel AutoDock4/Vina jobs distribution and result analysis. When the virtual screening project finishes, an open-office spreadsheet file opens with the ligands ranked by binding energy and distance to the active site. All results files can automatically be recorded on an USB-flash drive or on the hard-disk drive using VirtualBox. MOLA works inside a customized Live CD GNU/Linux operating system, developed by us, that bypass the original operating system installed on the computers used in the cluster. This operating system boots from a CD on the master node and then clusters other computers as slave nodes via ethernet connections. Conclusion MOLA is an ideal virtual screening tool for non-experienced users, with a limited number of multi-platform heterogeneous computers available and no access to dedicated Linux computer clusters. When a virtual screening project finishes, the computers can just be restarted to their original operating system. The originality of MOLA lies on the fact that, any platform-independent computer available can he added to the cluster, without ever using the computer hard-disk drive and without interfering with the installed operating system. With a cluster of 10 processors, and a

Database for High Throughput Screening Hits (dHITS): a simple tool to retrieve gene specific phenotypes from systematic screens done in yeast.

Science.gov (United States)

Chuartzman, Silvia G; Schuldiner, Maya

2018-03-25

In the last decade several collections of Saccharomyces cerevisiae yeast strains have been created. In these collections every gene is modified in a similar manner such as by a deletion or the addition of a protein tag. Such libraries have enabled a diversity of systematic screens, giving rise to large amounts of information regarding gene functions. However, often papers describing such screens focus on a single gene or a small set of genes and all other loci affecting the phenotype of choice ('hits') are only mentioned in tables that are provided as supplementary material and are often hard to retrieve or search. To help unify and make such data accessible, we have created a Database of High Throughput Screening Hits (dHITS). The dHITS database enables information to be obtained about screens in which genes of interest were found as well as the other genes that came up in that screen - all in a readily accessible and downloadable format. The ability to query large lists of genes at the same time provides a platform to easily analyse hits obtained from transcriptional analyses or other screens. We hope that this platform will serve as a tool to facilitate investigation of protein functions to the yeast community. © 2018 The Authors Yeast Published by John Wiley & Sons Ltd.

Questionnaire survey of current status and reserve for breast cancer screening in Mie prefecture. Achievement of a 50% participation rate

International Nuclear Information System (INIS)

Kobayashi, Shigeki; Tanaka, Yukio; Matsuo, Michiko

2012-01-01

Mie Medical Network of Breast Cancer Screening, a NPO, was assigned the task of breast cancer screening in Mie prefecture in April, 2010. For breast cancer screening in Mie prefecture in 2009, a questionnaire survey was performed toward both consigner and consignee. Consigners were local public offices managing breast cancer screening for local inhabitants, and consignees were facilities offering breast cancer screening. The number of breast cancer screening was investigated toward all 29 of consigners in Mie prefecture. The questionnaire survey was conducted toward all 52 of the facilities possessing mammography systems (breast cancer screening being performed at 48 of them) in Mie prefecture in 2009. We investigated the predictive additional number of breast cancer screening and also investigated the requisite number of staff to achieve the predictive maximum number of breast cancer screening. As a result, the total number of breast cancer screenings was 93,525, and the participation rate was 27.5% which was calculated by reduction of continuator in Mie prefecture in 2009. The continuator accounted for over 30% of all breast cancer screenings. The predictive additional number was 126,950, this indicates that a possible participation rate of 75.2% after 2011. To achieve this high participation rate, active support is essential for short-handed facilities, and about 20% increase of medical staff is necessary. To achieve a participation rate of over 50% as a goal, new screenees should be recruited and breast cancer screening of every other year should be enlightened. (author)

Source of vacuum electromagnetic zero-point energy and Dirac's large numbers hypothesis

International Nuclear Information System (INIS)

Simaciu, I.; Dumitrescu, G.

1993-01-01

The stochastic electrodynamics states that zero-point fluctuation of the vacuum (ZPF) is an electromagnetic zero-point radiation with spectral density ρ(ω)=ℎω 3 / 2π 2 C 3 . Protons, free electrons and atoms are sources for this radiation. Each of them absorbs and emits energy by interacting with ZPF. At equilibrium ZPF radiation is scattered by dipoles.Scattered radiation spectral density is ρ(ω,r) ρ(ω).c.σ(ω) / 4πr 2 . Radiation of dipole spectral density of Universe is ρ ∫ 0 R nρ(ω,r)4πr 2 dr. But if σ atom P e σ=σ T then ρ ρ(ω)σ T R.n. Moreover if ρ=ρ(ω) then σ T Rn = 1. With R = G M/c 2 and σ T ≅(e 2 /m e c 2 ) 2 ∝ r e 2 then σ T .Rn 1 is equivalent to R/r e = e 2 /Gm p m e i.e. the cosmological coincidence discussed in the context of Dirac's large-numbers hypothesis. (Author)

Strong Law of Large Numbers for Hidden Markov Chains Indexed by an Infinite Tree with Uniformly Bounded Degrees

Directory of Open Access Journals (Sweden)

Huilin Huang

2014-01-01

Full Text Available We study strong limit theorems for hidden Markov chains fields indexed by an infinite tree with uniformly bounded degrees. We mainly establish the strong law of large numbers for hidden Markov chains fields indexed by an infinite tree with uniformly bounded degrees and give the strong limit law of the conditional sample entropy rate.

Discovery of novel SERCA inhibitors by virtual screening of a large compound library.

Science.gov (United States)

Elam, Christopher; Lape, Michael; Deye, Joel; Zultowsky, Jodie; Stanton, David T; Paula, Stefan

2011-05-01

Two screening protocols based on recursive partitioning and computational ligand docking methodologies, respectively, were employed for virtual screens of a compound library with 345,000 entries for novel inhibitors of the enzyme sarco/endoplasmic reticulum calcium ATPase (SERCA), a potential target for cancer chemotherapy. A total of 72 compounds that were predicted to be potential inhibitors of SERCA were tested in bioassays and 17 displayed inhibitory potencies at concentrations below 100 μM. The majority of these inhibitors were composed of two phenyl rings tethered to each other by a short link of one to three atoms. Putative interactions between SERCA and the inhibitors were identified by inspection of docking-predicted poses and some of the structural features required for effective SERCA inhibition were determined by analysis of the classification pattern employed by the recursive partitioning models. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Batch fabrication of disposable screen printed SERS arrays.

Science.gov (United States)

Qu, Lu-Lu; Li, Da-Wei; Xue, Jin-Qun; Zhai, Wen-Lei; Fossey, John S; Long, Yi-Tao

2012-03-07

A novel facile method of fabricating disposable and highly reproducible surface-enhanced Raman spectroscopy (SERS) arrays using screen printing was explored. The screen printing ink containing silver nanoparticles was prepared and printed on supporting materials by a screen printing process to fabricate SERS arrays (6 × 10 printed spots) in large batches. The fabrication conditions, SERS performance and application of these arrays were systematically investigated, and a detection limit of 1.6 × 10(-13) M for rhodamine 6G could be achieved. Moreover, the screen printed SERS arrays exhibited high reproducibility and stability, the spot-to-spot SERS signals showed that the intensity variation was less than 10% and SERS performance could be maintained over 12 weeks. Portable high-throughput analysis of biological samples was accomplished using these disposable screen printed SERS arrays.

Sensitivity of 2-[18F]fluoro-2-deoxyglucose positron emission tomography for advanced colorectal neoplasms: a large-scale analysis of 7505 asymptomatic screening individuals.

Science.gov (United States)

Sekiguchi, Masau; Kakugawa, Yasuo; Terauchi, Takashi; Matsumoto, Minori; Saito, Hiroshi; Muramatsu, Yukio; Saito, Yutaka; Matsuda, Takahisa

2016-12-01

The sensitivity of 2-[ 18 F]fluoro-2-deoxyglucose positron emission tomography (FDG-PET) for advanced colorectal neoplasms among healthy subjects is not yet fully understood. The present study aimed to clarify the sensitivity by analyzing large-scale data from an asymptomatic screening population. A total of 7505 asymptomatic screenees who underwent both FDG-PET and colonoscopy at our Cancer Screening Division between February 2004 and March 2013 were analyzed. FDG-PET and colonoscopy were performed on consecutive days, and each examination was interpreted in a blinded fashion. The results of the two examinations were compared for each of the divided six colonic segments, with those from colonoscopy being set as the reference. The relationships between the sensitivity of FDG-PET and clinicopathological features of advanced neoplasms were also evaluated. Two hundred ninety-one advanced neoplasms, including 24 invasive cancers, were detected in 262 individuals. Thirteen advanced neoplasms (advanced adenomas) were excluded from the analysis because of the coexistence of lesions in the same colonic segment. The sensitivity, specificity, and positive and negative predictive values of FDG-PET for advanced neoplasms were 16.9 % [95 % confidence interval (CI) 12.7-21.8 %], 99.3 % (95 % CI 99.2-99.4 %), 13.5 % (95 % CI 10.1-17.6 %), and 99.4 % (95 % CI 99.3-99.5 %), respectively. The sensitivity was lower for lesions with less advanced histological grade, of smaller size, and flat-type morphology, and for those located in the proximal part of the colon. FDG-PET is believed to be difficult to use as a primary screening tool in population-based colorectal cancer screening because of its low sensitivity for advanced neoplasms. Even when it is used in opportunistic cancer screening, the limit of its sensitivity should be considered.

Valuing Equal Protection in Aviation Security Screening.

Science.gov (United States)

Nguyen, Kenneth D; Rosoff, Heather; John, Richard S

2017-12-01

The growing number of anti-terrorism policies has elevated public concerns about discrimination. Within the context of airport security screening, the current study examines how American travelers value the principle of equal protection by quantifying the "equity premium" that they are willing to sacrifice to avoid screening procedures that result in differential treatments. In addition, we applied the notion of procedural justice to explore the effect of alternative selective screening procedures on the value of equal protection. Two-hundred and twenty-two respondents were randomly assigned to one of three selective screening procedures: (1) randomly, (2) using behavioral indicators, or (3) based on demographic characteristics. They were asked to choose between airlines using either an equal or a discriminatory screening procedure. While the former requires all passengers to be screened in the same manner, the latter mandates all passengers undergo a quick primary screening and, in addition, some passengers are selected for a secondary screening based on a predetermined selection criterion. Equity premiums were quantified in terms of monetary cost, wait time, convenience, and safety compromise. Results show that equity premiums varied greatly across respondents, with many indicating little willingness to sacrifice to avoid inequitable screening, and a smaller minority willing to sacrifice anything to avoid the discriminatory screening. The selective screening manipulation was effective in that equity premiums were greater under selection by demographic characteristics compared to the other two procedures. © 2017 Society for Risk Analysis.

Breast cancer screening halves the risk of breast cancer death: a case-referent study

NARCIS (Netherlands)

Paap, Ellen; Verbeek, André L. M.; Botterweck, Anita A. M.; van Doorne-Nagtegaal, Heidi J.; Imhof-Tas, Mechli; de Koning, Harry J.; Otto, Suzie J.; de Munck, Linda; van der Steen, Annemieke; Holland, Roland; den Heeten, Gerard J.; Broeders, Mireille J. M.

2014-01-01

Large-scale epidemiologic studies have consistently demonstrated the effectiveness of mammographic screening programs, however the benefits are still subject to debate. We estimated the effect of the Dutch screening program on breast cancer mortality. In a large multi-region case-referent study, we

Impact of a new national screening policy for Down's syndrome in Denmark: population based cohort study

DEFF Research Database (Denmark)

Ekelund, Charlotte K; Jørgensen, Finn Stener; Petersen, Olav Bjørn

2008-01-01

OBJECTIVES: To evaluate the impact of a screening strategy in the first trimester, introduced in Denmark during 2004-6, on the number of infants born with Down's syndrome and the number of chorionic villus samplings and amniocenteses, and to determine detection and false positive rates...... and newborn infants with Down's syndrome diagnosed prenatally and postnatally and number of chorionic villus samplings and amniocenteses carried out. Secondary outcomes measured were number of women screened in 2005 and 2006, screen positive rate, and information on screening in 2005 and 2006 for infants...... with a postnatal diagnosis of Down's syndrome. RESULTS: The number of infants born with Down's syndrome decreased from 55-65 per year during 2000-4 to 31 in 2005 and 32 in 2006. The total number of chorionic villus samplings and amniocenteses carried out decreased from 7524 in 2000 to 3510 in 2006. The detection...

High Throughput, Label-free Screening Small Molecule Compound Libraries for Protein-Ligands using Combination of Small Molecule Microarrays and a Special Ellipsometry-based Optical Scanner.

Science.gov (United States)

Landry, James P; Fei, Yiyan; Zhu, X D

2011-12-01

Small-molecule compounds remain the major source of therapeutic and preventative drugs. Developing new drugs against a protein target often requires screening large collections of compounds with diverse structures for ligands or ligand fragments that exhibit sufficiently affinity and desirable inhibition effect on the target before further optimization and development. Since the number of small molecule compounds is large, high-throughput screening (HTS) methods are needed. Small-molecule microarrays (SMM) on a solid support in combination with a suitable binding assay form a viable HTS platform. We demonstrate that by combining an oblique-incidence reflectivity difference optical scanner with SMM we can screen 10,000 small-molecule compounds on a single glass slide for protein ligands without fluorescence labeling. Furthermore using such a label-free assay platform we can simultaneously acquire binding curves of a solution-phase protein to over 10,000 immobilized compounds, thus enabling full characterization of protein-ligand interactions over a wide range of affinity constants.

Finasteride Reduces Risk of Bladder Cancer in a Large Prospective Screening Study.