WorldWideScience

Sample records for amplification technology screening

  1. Nucleic acid amplification technology screening for hepatitis C virus and human immunodeficiency virus for blood donations

    International Nuclear Information System (INIS)

    To investigate the performance of the commercial Roche COBAS AmpliScreen assay, and demonstrate whether the COBAS AmpliScreen human immunodeficiency virus-1 (HIV-1) test, v1.5, and COBAS AmpliScreen hepatitis C virus (HCV) v 2.0 for screening for HIV-1 and HCV RNA in the donated blood units from which plasma mini pools were collected, by nucleic acid amplification technology (NAT), could detect the positive pools and reduce the risk of transmission of infections for those routinely tested by serological assays. The study was performed on 3288 plasma samples collected from blood donors in a period of 13 months, from August 2004 to August 2005, at Al-Hada Armed Forces Hospital, Molecular Pathology Laboratory, Taif, Kingdom of Saudi Arabia. The samples were tested by the reverse transcriptase polymerase chain reaction (RT-PCR) after RNA extraction (this represents the major method in NAT assays), in parallel with the routine serological testing to detect qualitatively for HIV-1 and HCV. The NAT assays that include an automated COBAS AmpliPrep system for RNA extraction and COBAS Amplicor Analyzer using AmpliScreen kits for RT-PCR assays, and the routine serological screening assays for the detection of the HIV-1 and HCV RNA in the plasma samples from the blood donors have shown to be a reliable combination that would meet our requirements. The collected data further confirms the results from the serological assays and enables us to decrease the residual risk of transmission to a minimum with the finding of no seronegative window period donation. The results demonstrate that out of 3288 samples, the percentages of RT-PCR (NAT) negative blood donations that were also confirmed as seronegative were 99% for HCV, and 99.1% for HIV-1. The modified combined systems (automated COBAS AmpliPrep system for RNA extraction and COBAS Amplicor Analyzer using AmpliScreen kits for RT-PCR assays) for NAT screening assays has allowed the release of all blood donations supplied in the

  2. Genomic Amplifications Cause False Positives in CRISPR Screens.

    Science.gov (United States)

    Sheel, Ankur; Xue, Wen

    2016-08-01

    In CRISPR-based screens for essential genes, Munoz and colleagues and Aguirre and colleagues show that gene-independent targeting of genomic amplifications in human cancer cell lines reduces proliferation or survival. The correlation between CRISPR target site copy number and lethality demonstrates the need for scrutiny and complementary approaches to rule out off-target effects and false positives in CRISPR screens. Cancer Discov; 6(8); 824-6. ©2016 AACR.See related article by Munoz et al., p. 900See related article by Aguirre et al., p. 914. PMID:27485003

  3. Social and political amplification of technological hazards

    International Nuclear Information System (INIS)

    Using an industrial explosion in Henderson, Nevada, as a case study, this paper examines three main issues: the efficacy of a technological hazard event in amplifying otherwise latent issues, the extent to which the hazard event can serve as a focusing event for substantive local and state policy initiatives, and the effect of fragmentation of political authority in managing technological hazards. The findings indicate that the explosion amplified several public safety issues and galvanized the public into pressing for major policy initiatives. However, notwithstanding the amplification of several otherwise latent issues, and the flurry of activities by the state and local governments, the hazard event did not seem to be an effective focusing event or trigger mechanism for substantive state and local policy initiatives. In addition, the study provides evidence of the need for a stronger nexus between political authority, land-use planning and technological hazard management

  4. Single Molecule Screening of Disease DNA Without Amplification

    Energy Technology Data Exchange (ETDEWEB)

    Ji-Young Lee

    2006-12-12

    The potential of single molecule detection as an analysis tool in biological and medical fields is well recognized today. This fast evolving technique will provide fundamental sensitivity to pick up individual pathogen molecules, and therefore contribute to a more accurate diagnosis and a better chance for a complete cure. Many studies are being carried out to successfully apply this technique in real screening fields. In this dissertation, several attempts are shown that have been made to test and refine the application of the single molecule technique as a clinical screening method. A basic applicability was tested with a 100% target content sample, using electrophoretic mobility and multiple colors as identification tools. Both electrophoretic and spectral information of individual molecule were collected within a second, while the molecule travels along the flow in a capillary. Insertion of a transmission grating made the recording of the whole spectrum of a dye-stained molecule possible without adding complicated instrumental components. Collecting two kinds of information simultaneously and combining them allowed more thorough identification, up to 98.8% accuracy. Probing mRNA molecules with fluorescently labeled cDNA via hybridization was also carried out. The spectral differences among target, probe, and hybrid were interpreted in terms of dispersion distances after transmission grating, and used for the identification of each molecule. The probes were designed to have the least background when they are free, but have strong fluorescence after hybridization via fluorescence resonance energy transfer. The mRNA-cDNA hybrids were further imaged in whole blood, plasma, and saliva, to test how far a crude preparation can be tolerated. Imaging was possible with up to 50% of clear bio-matrix contents, suggesting a simple lysis and dilution would be sufficient for imaging for some cells. Real pathogen DNA of human papillomavirus (HPV) type-I6 in human genomic DNA

  5. GMO detection in food and feed through screening by visual loop-mediated isothermal amplification assays.

    Science.gov (United States)

    Wang, Cong; Li, Rong; Quan, Sheng; Shen, Ping; Zhang, Dabing; Shi, Jianxin; Yang, Litao

    2015-06-01

    Isothermal DNA/RNA amplification techniques are the primary methodology for developing on-spot rapid nucleic acid amplification assays, and the loop-mediated isothermal amplification (LAMP) technique has been developed and applied in the detection of foodborne pathogens, plant/animal viruses, and genetically modified (GM) food/feed contents. In this study, one set of LAMP assays targeting on eight frequently used universal elements, marker genes, and exogenous target genes, such as CaMV35S promoter, FMV35S promoter, NOS, bar, cry1Ac, CP4 epsps, pat, and NptII, were developed for visual screening of GM contents in plant-derived food samples with high efficiency and accuracy. For these eight LAMP assays, their specificity was evaluated by testing commercial GM plant events and their limits of detection were also determined, which are 10 haploid genome equivalents (HGE) for FMV35S promoter, cry1Ac, and pat assays, as well as five HGE for CaMV35S promoter, bar, NOS terminator, CP4 epsps, and NptII assays. The screening applicability of these LAMP assays was further validated successfully using practical canola, soybean, and maize samples. The results suggested that the established visual LAMP assays are applicable and cost-effective for GM screening in plant-derived food samples. PMID:25822163

  6. Strand Invasion Based Amplification (SIBA®: a novel isothermal DNA amplification technology demonstrating high specificity and sensitivity for a single molecule of target analyte.

    Directory of Open Access Journals (Sweden)

    Mark J Hoser

    Full Text Available Isothermal nucleic acid amplification technologies offer significant advantages over polymerase chain reaction (PCR in that they do not require thermal cycling or sophisticated laboratory equipment. However, non-target-dependent amplification has limited the sensitivity of isothermal technologies and complex probes are usually required to distinguish between non-specific and target-dependent amplification. Here, we report a novel isothermal nucleic acid amplification technology, Strand Invasion Based Amplification (SIBA. SIBA technology is resistant to non-specific amplification, is able to detect a single molecule of target analyte, and does not require target-specific probes. The technology relies on the recombinase-dependent insertion of an invasion oligonucleotide (IO into the double-stranded target nucleic acid. The duplex regions peripheral to the IO insertion site dissociate, thereby enabling target-specific primers to bind. A polymerase then extends the primers onto the target nucleic acid leading to exponential amplification of the target. The primers are not substrates for the recombinase and are, therefore unable to extend the target template in the absence of the IO. The inclusion of 2'-O-methyl RNA to the IO ensures that it is not extendible and that it does not take part in the extension of the target template. These characteristics ensure that the technology is resistant to non-specific amplification since primer dimers or mis-priming are unable to exponentially amplify. Consequently, SIBA is highly specific and able to distinguish closely-related species with single molecule sensitivity in the absence of complex probes or sophisticated laboratory equipment. Here, we describe this technology in detail and demonstrate its use for the detection of Salmonella.

  7. The Center for Environmental Technology Innovative Technology Screening Process

    International Nuclear Information System (INIS)

    The Center for Environmental Technology's (CET) mission is to provide a fully integrated system for accelerated evaluation, development, commercialization, and public acceptance of creative environmental solutions which match the foremost demands in today's environmentally sensitive world. In short, CET will create a means to provide quick, effective solutions for environmental needs. To meet this mission objective, CET has created a unique and innovative approach to eliminating the usual barriers in developing and testing environmental technologies. The approach paves the way for these emerging, cutting-edge technologies by coordinating environmental restoration and waste management activities of industry, universities, and the government to: efficiently and effectively transfer technology to these users, provide market-driven, cost-effective technology programs to the public and DOE, and aid in developing innovative ideas by initiating efforts between DOE facilities and private industry. The central part to this mission is selecting and evaluating specific innovative technologies for demonstration and application at United States Department of Energy (DOE) installations. The methodology and criteria used for this selection, which is called the CET Innovative Technology Screening Process, is the subject of this paper. The selection criteria used for the screening process were modeled after other DOE technology transfer programs and were further developed by CET's Technology Screening and Evaluation Board (TSEB). The process benefits both CET and the proposing vendors by providing objective selection procedures based on predefined criteria. The selection process ensures a rapid response to proposing vendors, all technologies will have the opportunity to enter the selection process, and all technologies are evaluated on the same scale and with identical criteria

  8. Early amplification options.

    Science.gov (United States)

    Gabbard, Sandra Abbott; Schryer, Jennifer

    2003-01-01

    Children with permanent hearing loss have been remediated with hearing amplification devices for decades. The influx of young infants identified with hearing loss through successful newborn hearing screening programs has established a need for amplification resources for infants within the first six months of life. For the approximately two of every 1000 infants born who are identified with bilateral hearing loss [Mehl and Thomson, 1998, Pediatrics 101, p. e4], the use of amplification is commonly the first step in treating the sequella of their loss. The use of hearing aids, combined with early intervention, has been shown to significantly improve the speech and language skills of young children with hearing loss [Yoshinaga-Itano, 2000, Seminars in Hearing 21, p. 309]. Speech and language delays have contributed to compromised academic performance of school aged children with hearing loss [Johnson et al., 1997, Educational Audiology Handbook, Singular Publishing, San Diego]. Most hard-of-hearing and deaf children use hearing aids and other assistive listening devices every day throughout their lifetime and the life expectancy of a hearing aid is only five to eight years. The current challenge for pediatric audiologists is selecting and evaluating the available amplification to provide the best options for children and their families. Amplification technology has seen an explosion in growth the past few years and the options continue to expand rapidly. This article examines currently available amplification technology and reviews the selection criteria that may be used for infants and young children. Issues such as style, type, amplification features, signal processing strategies, and verification and validation tools are also discussed. PMID:14648816

  9. Optimal screening designs for biomedical technology

    Energy Technology Data Exchange (ETDEWEB)

    Torney, D.C.; Bruno, W.J.; Knill, E. [and others

    1997-10-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Screening a large number of different types of molecules to isolate a few with desirable properties is essential in biomedical technology. For example, trying to find a particular gene in the Human genome could be akin to looking for a needle in a haystack. Fortunately, testing of mixtures, or pools, of molecules allows the desirable ones to be identified, using a number of experiments proportional only to the logarithm of the total number of experiments proportional only to the logarithm of the total number of types of molecules. We show how to capitalize upon this potential by using optimize pooling schemes, or designs. We propose efficient non-adaptive pooling designs, such as {open_quotes}random sets{close_quotes} designs and modified {open_quotes}row and column{close_quotes} designs. Our results have been applied in the pooling and unique-sequence screening of clone libraries used in the Human Genome Project and in the mapping of Human chromosome 16. This required the use of liquid-transferring robots and manifolds--for the largest clone libraries. Finally, we developed an efficient technique for finding the posterior probability each molecule has the desirable property, given the pool assay results. This technique works well, in practice, even if there are substantial rates of errors in the pool assay data. Both our methods and our results are relevant to a broad spectrum of research in modern biology.

  10. A simple isothermal DNA amplification method to screen black flies for Onchocerca volvulus infection.

    Science.gov (United States)

    Alhassan, Andy; Makepeace, Benjamin L; LaCourse, Elwyn James; Osei-Atweneboana, Mike Y; Carlow, Clotilde K S

    2014-01-01

    Onchocerciasis is a debilitating neglected tropical disease caused by infection with the filarial parasite Onchocerca volvulus. Adult worms live in subcutaneous tissues and produce large numbers of microfilariae that migrate to the skin and eyes. The disease is spread by black flies of the genus Simulium following ingestion of microfilariae that develop into infective stage larvae in the insect. Currently, transmission is monitored by capture and dissection of black flies and microscopic examination of parasites, or using the polymerase chain reaction to determine the presence of parasite DNA in pools of black flies. In this study we identified a new DNA biomarker, encoding O. volvulus glutathione S-transferase 1a (OvGST1a), to detect O. volvulus infection in vector black flies. We developed an OvGST1a-based loop-mediated isothermal amplification (LAMP) assay where amplification of specific target DNA is detectable using turbidity or by a hydroxy naphthol blue color change. The results indicated that the assay is sensitive and rapid, capable of detecting DNA equivalent to less than one microfilaria within 60 minutes. The test is highly specific for the human parasite, as no cross-reaction was detected using DNA from the closely related and sympatric cattle parasite Onchocerca ochengi. The test has the potential to be developed further as a field tool for use in the surveillance of transmission before and after implementation of mass drug administration programs for onchocerciasis. PMID:25299656

  11. Screening of congenital heart disease patients using multiplex ligation-dependent probe amplification

    DEFF Research Database (Denmark)

    Sørensen, Karina Meden; El-Segaier, Milad; Fernlund, Eva;

    2012-01-01

    Recurrent copy number variants (CNVs) are found in a significant proportion of patients with congenital heart disease (CHD) and some of these CNVs are associated with other developmental defects. In some syndromic patients, CHD may be the first presenting symptom, thus screening of patients with...

  12. Materials and Technological Developement of Screen Printing in Transportation

    OpenAIRE

    Eszter Horvath; Gabor Henap; Gabor Harsanyi

    2012-01-01

    Screen printing is a widely used technology in electronic technology. Even though there were many developments in the technology, it is still being under improvement. This paper deals with the automotive industry related screen printing processes. The processes associated with layer deposition and the manufacturing process parameters, which affect the quality of the prints. As the repair of electronic control unit (ECU) used in road vehicles is nearly impossible the quality of printing theref...

  13. Rapid screening of innate immune gene expression in zebrafish using reverse transcription - multiplex ligation-dependent probe amplification

    Directory of Open Access Journals (Sweden)

    Spaink Herman P

    2011-06-01

    Full Text Available Abstract Background With the zebrafish increasingly being used in immunology and infectious disease research, there is a need for efficient molecular tools to evaluate immune gene expression in this model species. RT-MLPA (reverse transcription - multiplex ligation-dependent probe amplification provides a sensitive and reproducible method, in which fluorescently labelled amplification products of unique lengths are produced for a defined set of target transcripts. The method employs oligonucleotide probes that anneal to adjacent sites on a target sequence and are then joined by a heat-stable ligase. Subsequently, multiplex PCR with universal primers gives rise to amplicons that can be analyzed with standard sequencing equipment and relative quantification software. Allowing the simultaneous quantification of around 40 selected markers in a one-tube assay, RT-MLPA is highly useful for high-throughput screening applications. Findings We employed a dual-colour RT-MLPA probe design for chemical synthesis of probe pairs for 34 genes involved in Toll-like receptor signalling, transcriptional activation of the immune response, cytokine and chemokine production, and antimicrobial defence. In addition, six probe pairs were included for reference genes unaffected by infections in zebrafish. First, we established assay conditions for adult zebrafish infected with different strains of Mycobacterium marinum causing acute and chronic disease. Addition of competitor oligonucleotides was required to achieve peak heights in a similar range for genes with different expression levels. For subsequent analysis of embryonic samples it was necessary to adjust the amounts of competitor oligonucleotides, as the expression levels of several genes differed to a large extent between adult and embryonic tissues. Assay conditions established for one-day-old Salmonella typhimurium-infected embryos could be transferred without further adjustment to five-day-old M. marinum

  14. Feasibility of Technology Enabled Speech Disorder Screening.

    Science.gov (United States)

    Duenser, Andreas; Ward, Lauren; Stefani, Alessandro; Smith, Daniel; Freyne, Jill; Morgan, Angela; Dodd, Barbara

    2016-01-01

    One in twenty Australian children suffers from a speech disorder. Early detection of such problems can significantly improve literacy and academic outcomes for these children, reduce health and educational burden and ongoing social costs. Here we present the development of a prototype and feasibility tests of a screening and decision support tool to assess speech disorders in young children. The prototype incorporates speech signal processing, machine learning and expert knowledge to automatically classify phonemes of normal and disordered speech. We discuss these results and our future work towards the development of a mobile tool to facilitate broad, early speech disorder screening by non-experts. PMID:27440284

  15. Deletion screening of the Duchenne muscular dystrophy locus via multiplex DNA amplification.

    OpenAIRE

    Chamberlain, J S; Gibbs, R A; Ranier, J E; Nguyen, P N; Caskey, C. T.

    1988-01-01

    The application of recombinant DNA technology to prenatal diagnosis of many recessively inherited X-linked diseases is complicated by a high frequency of heterogeneous, new mutations (1). Partial gene deletions account for more than 50% of Duchenne muscular dystrophy (DMD) lesions, and approximately one-third of all cases result from a new mutation (2-5). We report the isolation and DNA sequence of several deletion prone exons from the human DMD gene. We also describe a rapid method capable o...

  16. Materials and Technological Developement of Screen Printing in Transportation

    Directory of Open Access Journals (Sweden)

    Eszter Horvath

    2012-06-01

    Full Text Available Screen printing is a widely used technology in electronic technology. Even though there were many developments in the technology, it is still being under improvement. This paper deals with the automotive industry related screen printing processes. The processes associated with layer deposition and the manufacturing process parameters, which affect the quality of the prints. As the repair of electronic control unit (ECU used in road vehicles is nearly impossible the quality of printing therefore unquestionable. It is very important that the accidents caused by mechanical failure must be kept as low as possible therefore the avoidanceof failure in screen printing is not only economical question but in case of transportation it is also question of road safety. Finally, an overview is given of the typical failure effect and possible causes appearing in screen printing.

  17. Barriers to adoption of recent technology in cervical screening

    Directory of Open Access Journals (Sweden)

    Jhala Darshana

    2007-01-01

    Full Text Available Abstract The Pap smear is one of the modern success stories in the field of preventive medicine. Since its introduction as a screening test, there has been a dramatic reduction in the incidence of cervical cancer. However, the search for a better screening test continues. The new technologies, including liquid-based cytology (LBC, Human Papilloma Virus (HPV testing and automated or machine-assisted screening have been introduced. However, there is continuous debate about whether society's limited resources are better spent on reaching the underserved rather than on these technologies. Another question is whether these technologies create yet another kind of disparity in delivering preventive care. For example, despite the wide use of LBC (99% of tests submitted to our laboratory are LBC, conventional Pap smears are still used to screen/follow up some women. It is not clear why some providers continue to prefer conventional smear over LBC and what are the barriers for adopting LBC in cervical cancer screening. We hypothesize the lower cost of conventional compared to LBC Pap testing, patient's lower socio-economic indices, a patient's medical history and provider's subspecialty/training all appear to play a role in the choice of using conventional Pap testing rather than LBC. Unintentionally, this choice results in repeat testing, delayed treatment and potentially higher costs than intended. The ultimate goal of this review article is to understand and explore possible barriers and disparities to adopting new technology in cancer screening.

  18. Randomly Amplified DNA Fingerprinting: A Culmination of DNA Marker Technologies Based on Arbitrarily-Primed PCR Amplification

    OpenAIRE

    Waldron Julie; Peace Cameron P.; Searle Iain R.; Furtado Agnelo; Wade Nick; Findlay Ian; Graham Michael W.; Carroll Bernard J.

    2002-01-01

    Arbitrarily-primed DNA markers can be very useful for genetic fingerprinting and for facilitating positional cloning of genes. This class of technologies is particularly important for less studied species, for which genome sequence information is generally not known. The technologies include Randomly Amplified Polymorphic DNA (RAPD), DNA Amplification Fingerprinting (DAF), and Amplified Fragment Length Polymorphism (AFLP). We have modified the DAF protocol to produce a robust PCR-based DNA ma...

  19. Outcomes in cervical screening using various cytology technologies

    DEFF Research Database (Denmark)

    Barken, Sidsel S; Rebolj, Matejka; Lynge, Elsebeth;

    2013-01-01

    Unlike for human papillomavirus screening, little is known about the possible age-dependent variation in the outcomes of cervical cytology screening. The aim of our study was to describe age-related outcomes of five cytological technologies in a population-based screening program targeting women...... signed out as normal, (3) liquid-based cytology (LBC) with 50% automatically signed out as normal, (4) LBC with 25% automatically signed out as normal, and (5) LBC with 25% automatically signed out as normal and with 16 preselected areas for attention in manual reading. We calculated proportion of...... aged 23-59 years. All cervical cytology from women residing in Copenhagen has been analyzed in the laboratory of the Department of Pathology, Hvidovre University Hospital. We studied five technology phases: (1) conventional cytology with manual reading, (2) conventional cytology with 50% automatically...

  20. Application of an in vitro-amplification assay as a novel pre-screening test for compounds inhibiting the aggregation of prion protein scrapie

    OpenAIRE

    Matthias Schmitz; Maria Cramm; Franc Llorens; Niccolò Candelise; Dominik Müller-Cramm; Daniela Varges; Schulz-Schaeffer, Walter J.; Saima Zafar; Inga Zerr

    2016-01-01

    In vitro amplification assays, such as real-time quaking-induced conversion (RT-QuIC) are used to detect aggregation activity of misfolded prion protein (PrP) in brain, cerebrospinal fluid (CSF) and urine samples from patients with a prion disease. We believe that the method also has a much broader application spectrum. In the present study, we applied RT-QuIC as a pre-screening test for substances that potentially inhibit the aggregation process of the cellular PrP (PrPC) to proteinase (PK)-...

  1. Large-screen display technology assessment for military applications

    Science.gov (United States)

    Blaha, Richard J.

    1990-08-01

    Full-color, large screen display systems can enhance military applications that require group presentation, coordinated decisions, or interaction between decision makers. The technology already plays an important role in operations centers, simulation facilities, conference rooms, and training centers. Some applications display situational, status, or briefing information, while others portray instructional material for procedural training or depict realistic panoramic scenes that are used in simulators. While each specific application requires unique values of luminance, resolution, response time, reliability, and the video interface, suitable performance can be achieved with available commercial large screen displays. Advances in the technology of large screen displays are driven by the commercial applications because the military applications do not provide the significant market share enjoyed by high definition television (HDTV), entertainment, advertisement, training, and industrial applications. This paper reviews the status of full-color, large screen display technologies and includes the performance and cost metrics of available systems. For this discussion, performance data is based upon either measurements made by our personnel or extractions from vendors' data sheets.

  2. THE CLONING OF HRNT-1 USING A COMBINATION OF cDNA LIBRARY SCREENING WITH BIOTIN-LABELED PROBE AND RAPID AMPLIFICATION OF cDNA ENDS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To clone the human counterpart of rat ZA73, EST cloned from rat tracheal epithelial (RTE) neoplastic transformed cell model induced by (a-particles radiation by using mRNA differential display. Methods: According to the sequence of rat ZA73, a probe was biotin-labeled to screen human cDNA library, and then the gene sequence was extended by RACE (rapid amplification of cDNA ends). Result: Human gene HRNT-1 (GenBank Accession Number: AF223393) is 4.256 kb in length, with an ORF located in the region between 254 and 3013 bp. 5' UTS (untranslated sequences) is 253 bp, 3' UTS is 1243 bp. Conclusion: The combination of cDNA library screening with biotin-labeled probes and RACE is an effective method to clone full-length cDNA, especially for sequences longer than 2 kb.

  3. Targeting helicase-dependent amplification products with an electrochemical genosensor for reliable and sensitive screening of genetically modified organisms.

    Science.gov (United States)

    Moura-Melo, Suely; Miranda-Castro, Rebeca; de-Los-Santos-Álvarez, Noemí; Miranda-Ordieres, Arturo J; Dos Santos Junior, J Ribeiro; da Silva Fonseca, Rosana A; Lobo-Castañón, Maria Jesús

    2015-08-18

    Cultivation of genetically modified organisms (GMOs) and their use in food and feed is constantly expanding; thus, the question of informing consumers about their presence in food has proven of significant interest. The development of sensitive, rapid, robust, and reliable methods for the detection of GMOs is crucial for proper food labeling. In response, we have experimentally characterized the helicase-dependent isothermal amplification (HDA) and sequence-specific detection of a transgene from the Cauliflower Mosaic Virus 35S Promoter (CaMV35S), inserted into most transgenic plants. HDA is one of the simplest approaches for DNA amplification, emulating the bacterial replication machinery, and resembling PCR but under isothermal conditions. However, it usually suffers from a lack of selectivity, which is due to the accumulation of spurious amplification products. To improve the selectivity of HDA, which makes the detection of amplification products more reliable, we have developed an electrochemical platform targeting the central sequence of HDA copies of the transgene. A binary monolayer architecture is built onto a thin gold film where, upon the formation of perfect nucleic acid duplexes with the amplification products, these are enzyme-labeled and electrochemically transduced. The resulting combined system increases genosensor detectability up to 10(6)-fold, allowing Yes/No detection of GMOs with a limit of detection of ∼30 copies of the CaMV35S genomic DNA. A set of general utility rules in the design of genosensors for detection of HDA amplicons, which may assist in the development of point-of-care tests, is also included. The method provides a versatile tool for detecting nucleic acids with extremely low abundance not only for food safety control but also in the diagnostics and environmental control areas. PMID:26198403

  4. Screening Technologies for Target Identification in Pancreatic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Michl, Patrick, E-mail: michlp@med.uni-marburg.de; Ripka, Stefanie; Gress, Thomas; Buchholz, Malte [Department of Gastroenterology and Endocrinology, University Hospital, Philipps-University Marburg, Baldinger Strasse, D-35043 Marburg (Germany)

    2010-12-29

    Pancreatic cancer exhibits an extraordinarily high level of resistance to almost any kind of systemic therapy evaluated in clinical trials so far. Therefore, the identification of novel therapeutic targets is urgently required. High-throughput screens have emerged as an important tool to identify putative targets for diagnosis and therapy in an unbiased manner. More than a decade ago, microarray technology was introduced to identify differentially expressed genes in pancreatic cancer as compared to normal pancreas, chronic pancreatitis and other cancer types located in close proximity to the pancreas. In addition, proteomic screens have facilitated the identification of differentially secreted proteins in body fluids of pancreatic cancer patients, serving as possible biomarkers. Recently, RNA interference-based loss-of-function screens have been used to identify functionally relevant genes, whose knock-down has impact on pancreatic cancer cell viability, thereby representing potential new targets for therapeutic intervention. This review summarizes recent results of transcriptional, proteomic and functional screens in pancreatic cancer and discusses potentials and limitations of the respective technologies as well as their impact on future therapeutic developments.

  5. Screening Technologies for Target Identification in Pancreatic Cancer

    International Nuclear Information System (INIS)

    Pancreatic cancer exhibits an extraordinarily high level of resistance to almost any kind of systemic therapy evaluated in clinical trials so far. Therefore, the identification of novel therapeutic targets is urgently required. High-throughput screens have emerged as an important tool to identify putative targets for diagnosis and therapy in an unbiased manner. More than a decade ago, microarray technology was introduced to identify differentially expressed genes in pancreatic cancer as compared to normal pancreas, chronic pancreatitis and other cancer types located in close proximity to the pancreas. In addition, proteomic screens have facilitated the identification of differentially secreted proteins in body fluids of pancreatic cancer patients, serving as possible biomarkers. Recently, RNA interference-based loss-of-function screens have been used to identify functionally relevant genes, whose knock-down has impact on pancreatic cancer cell viability, thereby representing potential new targets for therapeutic intervention. This review summarizes recent results of transcriptional, proteomic and functional screens in pancreatic cancer and discusses potentials and limitations of the respective technologies as well as their impact on future therapeutic developments

  6. Screening applications in drug discovery based on microfluidic technology.

    Science.gov (United States)

    Eribol, P; Uguz, A K; Ulgen, K O

    2016-01-01

    Microfluidics has been the focus of interest for the last two decades for all the advantages such as low chemical consumption, reduced analysis time, high throughput, better control of mass and heat transfer, downsizing a bench-top laboratory to a chip, i.e., lab-on-a-chip, and many others it has offered. Microfluidic technology quickly found applications in the pharmaceutical industry, which demands working with leading edge scientific and technological breakthroughs, as drug screening and commercialization are very long and expensive processes and require many tests due to unpredictable results. This review paper is on drug candidate screening methods with microfluidic technology and focuses specifically on fabrication techniques and materials for the microchip, types of flow such as continuous or discrete and their advantages, determination of kinetic parameters and their comparison with conventional systems, assessment of toxicities and cytotoxicities, concentration generations for high throughput, and the computational methods that were employed. An important conclusion of this review is that even though microfluidic technology has been in this field for around 20 years there is still room for research and development, as this cutting edge technology requires ingenuity to design and find solutions for each individual case. Recent extensions of these microsystems are microengineered organs-on-chips and organ arrays. PMID:26865904

  7. Comparison of Two Amplification Technologies for Detection and Quantitation of Human Immunodeficiency Virus Type 1 RNA in the Female Genital Tract

    OpenAIRE

    Bremer, James; Nowicki, Marek; Beckner, Suzanne; Brambilla, Donald; Cronin, Mike; Herman, Steven; Kovacs, Andrea; Reichelderfer, Patricia

    2000-01-01

    Human immunodeficiency virus type 1 (HIV-1) RNA levels in female genital tract and peripheral blood samples were compared using two commercial amplification technologies: the Roche AMPLICOR HIV-1 MONITOR test and either the Organon Teknika nucleic acid sequence-based amplification (NASBA-QT) assay or the NucliSens assay. Estimates of HIV-1 RNA copy number were derived from internal kit standards and analyzed unadjusted and adjusted to a common set of external standards. We found a discordance...

  8. Screening for subtelomeric rearrangements in 210 patients with unexplained mental retardation using multiplex ligation dependent probe amplification (MLPA).

    NARCIS (Netherlands)

    Koolen, D.A.; Nillesen, W.M.; Versteeg, M.H.; Merkx, G.F.M.; Knoers, N.V.A.M.; Kets, M.; Vermeer, S.; Ravenswaaij-Arts, C.M.A. van; Kovel, C.G.F. de; Brunner, H.G.; Smeets, D.F.C.M.; Vries, L.B.A. de; Sistermans, E.A.

    2004-01-01

    BACKGROUND: Subtelomeric rearrangements contribute to idiopathic mental retardation and human malformations, sometimes as distinct mental retardation syndromes. However, for most subtelomeric defects a characteristic clinical phenotype remains to be elucidated. OBJECTIVE: To screen for submicroscopi

  9. National Security Science and Technology Initiative: Air Cargo Screening

    Energy Technology Data Exchange (ETDEWEB)

    Bingham, Philip R [ORNL; White, Tim [Pacific Northwest National Laboratory (PNNL); Cespedes, Ernesto [Idaho National Laboratory (INL); Bowerman, Biays [Brookhaven National Laboratory (BNL); Bush, John [Battelle

    2010-11-01

    The non-intrusive inspection (NII) of consolidated air cargo carried on commercial passenger aircraft continues to be a technically challenging, high-priority requirement of the Department of Homeland Security's Science and Technology Directorate (DHS S&T), the Transportation Security Agency and the Federal Aviation Administration. The goal of deploying a screening system that can reliably and cost-effectively detect explosive threats in consolidated cargo without adversely affecting the flow of commerce will require significant technical advances that will take years to develop. To address this critical National Security need, the Battelle Memorial Institute (Battelle), under a Cooperative Research and Development Agreement (CRADA) with four of its associated US Department of Energy (DOE) National Laboratories (Oak Ridge, Pacific Northwest, Idaho, and Brookhaven), conducted a research and development initiative focused on identifying, evaluating, and integrating technologies for screening consolidated air cargo for the presence of explosive threats. Battelle invested $8.5M of internal research and development funds during fiscal years 2007 through 2009. The primary results of this effort are described in this document and can be summarized as follows: (1) Completed a gap analysis that identified threat signatures and observables, candidate technologies for detection, their current state of development, and provided recommendations for improvements to meet air cargo screening requirements. (2) Defined a Commodity/Threat/Detection matrix that focuses modeling and experimental efforts, identifies technology gaps and game-changing opportunities, and provides a means of summarizing current and emerging capabilities. (3) Defined key properties (e.g., elemental composition, average density, effective atomic weight) for basic commodity and explosive benchmarks, developed virtual models of the physical distributions (pallets) of three commodity types and three

  10. Technology recommendations for pre-screening of IAEA swipe samples

    Energy Technology Data Exchange (ETDEWEB)

    Steeb, Jennifer L. [Argonne National Lab. (ANL), Argonne, IL (United States); Smith, Nicholas A. [Argonne National Lab. (ANL), Argonne, IL (United States); Lee, Denise L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Huckabay, Heath A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ticknor, Brian W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    Argonne and Oak Ridge National Laboratories have prepared an analysis of recommended, possible, and not recommended technologies for pre-screening and prioritizing IAEA swipes. The analytical techniques listed under the recommended technology list are the most promising techniques available to date. The recommended list is divided into two sections: Argonne’s recommended techniques and Oak Ridge’s recommended techniques. This list was divided based upon the expertise of staff in each subject area and/or the instrumentation available at each laboratory. The following section, titled Possible Techniques, is a list of analytical techniques that could be used for pre-screening and prioritizing swipes if additional instrumentation and effort were provided. These techniques are not necessarily top priority, but should not be discounted for future or expanded efforts. Lastly, a list of not recommended techniques is provided to outline the analytical methods and instrumentation that were investigated by each lab but deemed not suitable for this task. In addition to the recommendation list, a short procedure is provided outlining the steps followed for destructive analysis by the Network of Analytical Laboratories (NWAL) for determination of uranium concentrations, isotopic content of sample and swipe. Swipes generated for this project will be given to ORNL’s NWAL laboratory for analysis after analysis by other techniques at both laboratories.

  11. Technology recommendations for pre-screening of IAEA swipe samples

    International Nuclear Information System (INIS)

    Argonne and Oak Ridge National Laboratories have prepared an analysis of recommended, possible, and not recommended technologies for pre-screening and prioritizing IAEA swipes. The analytical techniques listed under the recommended technology list are the most promising techniques available to date. The recommended list is divided into two sections: Argonne's recommended techniques and Oak Ridge's recommended techniques. This list was divided based upon the expertise of staff in each subject area and/or the instrumentation available at each laboratory. The following section, titled Possible Techniques, is a list of analytical techniques that could be used for pre-screening and prioritizing swipes if additional instrumentation and effort were provided. These techniques are not necessarily top priority, but should not be discounted for future or expanded efforts. Lastly, a list of not recommended techniques is provided to outline the analytical methods and instrumentation that were investigated by each lab but deemed not suitable for this task. In addition to the recommendation list, a short procedure is provided outlining the steps followed for destructive analysis by the Network of Analytical Laboratories (NWAL) for determination of uranium concentrations, isotopic content of sample and swipe. Swipes generated for this project will be given to ORNL's NWAL laboratory for analysis after analysis by other techniques at both laboratories.

  12. The Use of Biochip Array Technology for Rapid Multimycotoxin Screening.

    Science.gov (United States)

    Plotan, Monika; Devlin, Raymond; Porter, Jonathan; Benchikh, M El Ouard; Rodríguez, María Luz; McConnell, R Ivan; FitzGerald, S Peter

    2016-07-01

    The main known groups of mycotoxins are aflatoxins, fumonisins, ochratoxins, type A trichothecenes (T-2 toxin and HT-2 toxin), type B trichothecenes (deoxynivalenol), and zearalenones. They are harmful to humans, domestic animals, and livestock. In Europe, maximum permitted limits for aflatoxin B1 are set, and guidance levels are recommended for the other mycotoxins. This study applied biochip array technology to semiquantitative multimycotoxin screening at different levels to facilitate the verification of the compliance of feed material with acceptable safety standards. This application was developed and validated based on European Commission Decision No. 2002/657/EC. After a single generic sample-preparation method, simultaneous competitive chemiluminescent immunoassays were used and applied to the Evidence Investigator analyzer. The r and within-laboratory R values showed low overall CVs (10.6 and 11.6%, respectively). Low matrix effect and, consequently, low decision limits and detection capabilities proved the high sensitivity of the technology. The overall average recovery was 104%. Samples (n = 16) investigated within the Food Analysis Performance Assessment Scheme (FAPAS) program showed excellent correlation to assigned values. FAPAS proficiency-testing feed samples (n = 10) were within the schemes' z-score ±2 range. The authentic feed samples survey showed excellent correlation with LC-MS/MS. This application is, therefore, reliable and represents an innovative, cost-effective, and multianalytical tool for mycotoxin screening. PMID:27455929

  13. e-Health technologies for adult hearing screening

    Directory of Open Access Journals (Sweden)

    S. Stenfelt

    2011-03-01

    Full Text Available The development of hearing diagnosis methods and hearing screening methods are not isolated phenomena: they are intimately related to changes in the cultural background and to advances in fields of medicine and engineering. In the recent years, there has been a rapid evolution in the development of fast, easy and reliable techniques for lowcost hearing screening initiatives. Since adults and elderly people typically experience a reduced hearing ability in challenging listening situations [e.g., in background noise, in reverberation, or with competing speech (Pichora‑Fuller & Souza, 2003], these newly developed screening tests mainly rely on the recognition of speech stimuli in noise, so that the real experienced listening difficulties can be effectively targeted (Killion & Niquette, 2000. New tests based on the recognition of speech in noise are being developed on portable, battery- operated devices (see, for example, Paglialonga et al., 2011, or distributed diffusely using information and communication technologies. The evolutions of e-Health and telemedicine have shifted focus from patients coming to the hearing clinic for hearing health evaluation towards the possibility of evaluating the hearing status remotely at home. So far, two ways of distributing the hearing test have primarily been used: ordinary telephone networks (excluding mobile networks and the internet. When using the telephone network for hearing screening, the predominantly test is a speech-in-noise test often referred to as the digit triplet test where the subjects hearing status is evaluated as the speech-to-noise threshold for spoken digits. This test is today available in some ten countries in Europe, North America and Australia. The use of internet as testing platform allows several different types of hearing assessment tests such as questionnaires, different types of speech in noise tests, temporal gap detection, sound localization (minimum audible angle, and spectral

  14. Highly sensitive chemiluminescence technology for protein detection using aptamer-based rolling circle amplification platform

    Institute of Scientific and Technical Information of China (English)

    Zhi-Juan Cao; Qian-Wen Peng; Xue Qiu; Cai-Yun Liu; Jian-Zhong Lu

    2011-01-01

    A robust, selective and highly sensitive chemiluminescent (CL) platform for protein assay was presented in this paper. This novel CL approach utilized rolling circle amplification (RCA) as a signal enhancement technique and the 96-well plate as the immobilization and separation carrier. Typically, the antibody immobilized on the surface of 96-well plate was sandwiched with the protein target and the aptamer-primer sequence. This aptamer-primer sequence was then employed as the primer of RCA. Based on this design, a number of the biotinylated probes and streptavidin-horseradish peroxidase (SA-HRP) were captured on the plate, and the CL signal was amplified. In summary, our results demonstrated a robust biosensor with a detection limit of 10 fM that is easy to be established and utilized, and devoid of light source. Therefore, this new technique .will broaden the perspective for future development of DNA-based biosensors for the detection of other protein biomarkers related to clinical diseases, by taking advantages of high sensitivity and selectivity.

  15. X-231B technology demonstration for in situ treatment of contaminated soil: Technology evaluation and screening

    International Nuclear Information System (INIS)

    The Portsmouth Gaseous Diffusion Plant (Ports) is located approximately 70 miles south of Columbus in southern Ohio. Among the several waste management units on the facility, the X-231B unit consists of two adjacent oil biodegradation plots. The plots encompass ∼ 0.8 acres and were reportedly used from 1976 to 1983 for the treatment and disposal of waste oils and degreasing solvents, some containing uranium-235 and technetium-99. The X-231B unit is a regulated solid waste management unit (SWMU) under the Resource Conservation and Recovery Act (RCRA). The X-231B unit is also a designated SWMU located within Quadrant I of the site as defined in an ongoing RCRA Facilities Investigation and Corrective Measures Study (RFI/CMS). Before implementing one or more Technology Demonstration Project must be completed. The principal goal of this project was to elect and successfully demonstrate one ore more technologies for effective treatment of the contaminated soils associated with the X-231B unit at PORTS. The project was divided into two major phases. Phase 1 involved a technology evaluation and screening process. The second phase (i.e., Phase 2) was to involve field demonstration, testing and evaluation of the technology(s) selected during Phase 1. This report presents the methods, results, and conclusions of the technology evaluation and screening portion of the project

  16. Screening for copy number alterations in loci associated with autism spectrum disorders by two-color multiplex ligation-dependent probe amplification

    DEFF Research Database (Denmark)

    Bremer, Anna; Giacobini, Maibritt; Nordenskjöld, Magnus;

    2010-01-01

    identified in a subgroup of individuals with ASD using array technology. Adequate genetic testing for these genomic imbalances have not yet been widely implemented in the diagnostic setting due to lack of feasible and cost-effective methods as well as difficulties to interpret the clinical significance of...... these small copy number variants (CNVs). We developed a multiplex ligation-dependent probe amplification (MLPA) assay to investigate its usefulness for detection of copy number alterations (CNAs) in autistic patients. This test proved to be easy to perform, fast, cost-effective, and suitable for...... analysis of a continuously increasing number of CNAs associated with autism. Our result show that MLPA assay is an easy and cost-effective method for the identification of selected CNAs in diagnostic laboratories....

  17. Overview of DOE's field screening technology development activities

    International Nuclear Information System (INIS)

    The Department of Energy (DOE) has recently created the Office of Environmental Restoration and Waste Management, into which it consolidated those activities. Within this new organization, the Office of Technology Development (OTD) is responsible for research, development, demonstration, testing, and evaluation (RDDT ampersand E) activities aimed at meeting DOE cleanup goals, while minimizing cost and risk. Site characterization using traditional drilling, sampling, and analytical methods comprises a significant part of the environmental restoration efforts in terms of both cost and time to accomplish. It can also be invasive and create additional pathways for spread of contaminants. Consequently, DOE is focusing on site characterization as one of the areas in which significant technological advances are possible which will decrease cost, reduce risk, and shorten schedules for achieving restoration goals. DOE is investing considerably in R ampersand D and demonstration activities which will improve the abilities to screen chemical, radiological, and physical parameters in the field. This paper presents an overview of the program objectives and status and reviews some of the projects which are currently underway in the area. 1 ref

  18. Small Screen Technology Use among Indigenous Boarding School Adolescents from Remote Regions of Western Australia

    Science.gov (United States)

    Johnson, Genevieve Marie; Oliver, Rhonda

    2014-01-01

    The uptake of small screen technology by adolescents is widespread, particularly in industrial nations. Whether the same is true for Australian Aboriginal youth is less clear as there is a dearth of research in this regard. Therefore, in this exploratory study the use of small screen technology by Indigenous students was examined. Twenty-four…

  19. A method for the amplification of chemically induced transformation in C3H/10T1/2 clone 8 cells: its use as a potential screening assay.

    Science.gov (United States)

    Schechtman, L M; Kiss, E; McCarvill, J; Nims, R; Kouri, R E; Lubet, R A

    1987-09-01

    A method has been developed by which to amplify expression of phenotypic transformation of C3H/10T1/2 clone 8 mouse embryo cells not otherwise observed in the standard transformation assay. The expression of transformed foci was amplified by subcultivating chemically treated target cells after they had reached confluence and replating them at subconfluent cell densities. Conditions leading to the expression of the highest numbers of transformed foci include a) a cell seeding density for chemical treatment of 1 X 10(4) cells/dish, b) subculture 4 weeks after treatment, and c) replating cells at a density of 2 X 10(5) cells/-dish. Agents capable of inducing transformation in the standard assay (e.g., 4,4'-bis(dimethylamino)benzophenone, benzo[a]pyrene, 7,12-dimethylbenz[a]anthracene, and others) also yielded transformation in the replating assay. The more marginal transforming activities of chemicals such as ethyl methanesulfonate, 7-(bromomethyl)-12-methylbenz[a]anthracene, and N-methyl-N'-nitro-N-nitrosoguanidine were enhanced by the amplification procedure. Compounds that failed to elicit focal transformation in the standard assay (e.g., dibenz[a,h]anthracene, Tris(2,3-dibromopropyl) phosphate, lead acetate, benzidine, propyleneimine, N-hydroxy-2-fluorenylacetamide, and numerous other compounds of various chemical classes) induced significant levels of phenotypic transformation upon amplification. Noncarcinogens (e.g., phenanthrene, anthracene, 2-aminobiphenyl, cycloheximide, and others) failed to cause significant phenotypic transformation even when cells were replated. To further enhance the applicability of this new replating system, an exogenous source of metabolic activation was added: a 9,000 X g supernatant from Aroclor 1254-induced rat hepatic S-9. This activation system was found a) to be only minimally cytotoxic by itself and b) to be able to mediate NADPH-dependent, dose-dependent toxicity, and transformation by activating the procarcinogens

  20. Touch Screen Technology Adoption and Utilisation by Educators in Early Childhood Educational Institutions

    DEFF Research Database (Denmark)

    Plumb, Melinda; Kautz, Karlheinz; Tootell, Holly

    2013-01-01

    The adoption of information and communication technology (ICT) in early childhood educational settings, in particular touch screen technology such as interactive whiteboards and tablet computing devices has potential for use within early childhood educational institutions. We conducted a literature...... that can support the successful implementation of touch screen technology within early childhood educational institutions....... in regards to touch screen technology in early childhood, particularly from a process perspective, and suggest that further research is required to understand the interplay between individual actions and organisational structural influences. This will contribute to the development of an understanding...

  1. Technologies for pre-screening IAEA swipe samples

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Nicholas A. [Argonne National Lab. (ANL), Argonne, IL (United States); Steeb, Jennifer L. [Argonne National Lab. (ANL), Argonne, IL (United States); Lee, Denise L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Huckabay, Heath A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ticknor, Brian W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-11-09

    During the course of International Atomic Energy Agency (IAEA) inspections, many samples are taken for the purpose of verifying the declared facility activities and identifying any possible undeclared activities. One of these sampling techniques is the environmental swipe sample. Due to the large number of samples collected, and the amount of time that is required to analyze them, prioritizing these swipes in the field or upon receipt at the Network of Analytical Laboratories (NWAL) will allow sensitive or mission-critical analyses to be performed sooner. As a result of this study, technologies were placed into one of three categories: recommended, promising, or not recommended. Both neutron activation analysis (NAA) and X-ray fluorescence (XRF) are recommended for further study and possible field deployment. These techniques performed the best in initial trials for pre-screening and prioritizing IAEA swipes. We learned that for NAA more characterization of cold elements (such as calcium and magnesium) would need to be emphasized, and for XRF it may be appropriate to move towards a benchtop XRF versus a handheld XRF due to the increased range of elements available on benchtop equipment. Promising techniques that will require additional research and development include confocal Raman microscopy, fluorescence microscopy, and infrared (IR) microscopy. These techniques showed substantive responses to uranium compounds, but expensive instrumentation upgrades (confocal Raman) or university engagement (fluorescence microscopy) may be necessary to investigate the utility of the techniques completely. Point-and-shoot (handheld) Raman and attenuated total reflectance–infrared (ATR-IR) measurements are not recommended, as they have not shown enough promise to continue investigations.

  2. Technologies for pre-screening IAEA swipe samples

    International Nuclear Information System (INIS)

    During the course of International Atomic Energy Agency (IAEA) inspections, many samples are taken for the purpose of verifying the declared facility activities and identifying any possible undeclared activities. One of these sampling techniques is the environmental swipe sample. Due to the large number of samples collected, and the amount of time that is required to analyze them, prioritizing these swipes in the field or upon receipt at the Network of Analytical Laboratories (NWAL) will allow sensitive or mission-critical analyses to be performed sooner. As a result of this study, technologies were placed into one of three categories: recommended, promising, or not recommended. Both neutron activation analysis (NAA) and X-ray fluorescence (XRF) are recommended for further study and possible field deployment. These techniques performed the best in initial trials for pre-screening and prioritizing IAEA swipes. We learned that for NAA more characterization of cold elements (such as calcium and magnesium) would need to be emphasized, and for XRF it may be appropriate to move towards a benchtop XRF versus a handheld XRF due to the increased range of elements available on benchtop equipment. Promising techniques that will require additional research and development include confocal Raman microscopy, fluorescence microscopy, and infrared (IR) microscopy. These techniques showed substantive responses to uranium compounds, but expensive instrumentation upgrades (confocal Raman) or university engagement (fluorescence microscopy) may be necessary to investigate the utility of the techniques completely. Point-and-shoot (handheld) Raman and attenuated total reflectance–infrared (ATR-IR) measurements are not recommended, as they have not shown enough promise to continue investigations.

  3. Deletion/duplication mutation screening of TP53 gene in patients with transitional cell carcinoma of urinary bladder using multiplex ligation-dependent probe amplification.

    Science.gov (United States)

    Bazrafshani, Mohammad Reza R; Nowshadi, Pouriaali A; Shirian, Sadegh; Daneshbod, Yahya; Nabipour, Fatemeh; Mokhtari, Maral; Hosseini, Fatemehsadat; Dehghan, Somayeh; Saeedzadeh, Abolfazl; Mosayebi, Ziba

    2016-02-01

    Bladder cancer is a molecular disease driven by the accumulation of genetic, epigenetic, and environmental factors. The aim of this study was to detect the deletions/duplication mutations in TP53 gene exons using multiplex ligation-dependent probe amplification (MLPA) method in the patients with transitional cell carcinoma (TCC). The achieved formalin-fixed paraffin-embedded tissues from 60 patients with TCC of bladder were screened for exonal deletions or duplications of every 12 TP53 gene exons using MLPA. The pathological sections were examined by three pathologists and categorized according to the WHO scoring guideline as 18 (30%) grade I, 22 (37%) grade II, 13 (22%) grade III, and 7 (11%) grade IV cases of TCC. None mutation changes of TP53 gene were detected in 24 (40%) of the patients. Furthermore, mutation changes including, 15 (25%) deletion, 17 (28%) duplication, and 4 (7%) both deletion and duplication cases were observed among 60 samples. From 12 exons of TP53 gene, exon 1 was more subjected to exonal deletion. Deletion of exon 1 of TP53 gene has occurred in 11 (35.4%) patients with TCC. In general, most mutations of TP53, either deletion or duplication, were found in exon 1, which was statistically significant. In addition, no relation between the TCC tumor grade and any type of mutation were observed in this research. MLPA is a simple and efficient method to analyze genomic deletions and duplications of all 12 exons of TP53 gene. The finding of this report that most of the mutations of TP53 occur in exon 1 is in contrast to that of the other reports suggesting that exons 5-8 are the most (frequently) mutated exons of TP53 gene. The mutations of exon 1 of TP53 gene may play an important role in the tumorogenesis of TCC. PMID:26685928

  4. Impact of new screening technologies: should we screen and does phenotype influence this decision?

    Science.gov (United States)

    Bonham, James Robert

    2013-07-01

    The early detection offered by newborn screening for phenylketonuria clearly demonstrates the benefits for patients with inherited metabolic disorders of well organised screening programmes. It is therefore perhaps surprising that 20 years after the introduction of electrospray MS/MS methods to support expanded newborn screening that considerable international variation in practice, not linked to economic factors, exists. It is likely that the commonly used criteria to assess the suitability of a disorder for screening need to be re-appraised as they apply to rare disorders. In addition, national differences in the pattern of policy making may influence the strategy adopted and these different approaches need to be scrutinised more closely. Despite this contextual variation a number of real issues do need to be addressed as the range of conditions included in screening programmes continues to increase. These include the need for well organised outcome studies based upon agreed case definitions and comparable treatment regimens; the need for appropriate information for parents to support them before and during the screening odyssey; an improved understanding of the impact of false positive results and in particular a clearer understanding of the way in which some of the problems resulting from false positive results can be avoided or ameliorated; the challenge offered by mild or atypical screen positive cases and the consequent design of proportionate treatment options. A thorough understanding of the genetic, biochemical and clinical features of screen positive cases supported by effective international outcome studies is required to optimise both screening and treatment strategies. PMID:23508696

  5. Screen Printed PZT Thick Films Using Composite Film Technology

    OpenAIRE

    Dorey, R; Whatmore, R; Beeby, S. P.; Torah, R; White, N.

    2003-01-01

    A spin coating composite sol gel technique for producing lead zirconate titanate (PZT) thick films has been modified for use with screen printing techniques. The resulting screen printing technique can be used to produce 10 ?m thick films in a single print. The resultant films are porous but the density can be increased through the use of repeated sol infiltration/pyrolysis treatments to yield a high density film. When fired at 710°C the composite screen printed films have dielectric and piez...

  6. Double regenerative amplification of picosecond pulses

    Science.gov (United States)

    Bai, Zhen-ao; Chen, Li-yuan; Bai, Zhen-xu; Chen, Meng; Li, Gang

    2012-04-01

    An double Nd:YAG regenerative amplification picosecond pulse laser is demonstrated under the semiconductor saturable absorption mirror(SESAM) mode-locking technology and regenerative amplification technology, using BBO crystal as PC electro-optic crystal. The laser obtained is 20.71ps pulse width at 10 KHz repetition rate, and the energy power is up to 4W which is much larger than the system without pre-amplification. This result will lay a foundation for the following amplification.

  7. Droplet microfluidic technology for single-cell high-throughput screening

    OpenAIRE

    Brouzes, Eric; Medkova, Martina; Savenelli, Neal; Marran, Dave; Twardowski, Mariusz; Hutchison, J. Brian; Rothberg, Jonathan M.; Link, Darren R; Perrimon, Norbert; Samuels, Michael L

    2009-01-01

    We present a droplet-based microfluidic technology that enables high-throughput screening of single mammalian cells. This integrated platform allows for the encapsulation of single cells and reagents in independent aqueous microdroplets (1 pL to 10 nL volumes) dispersed in an immiscible carrier oil and enables the digital manipulation of these reactors at a very high-throughput. Here, we validate a full droplet screening workflow by conducting a droplet-based cytotoxicity screen. To perform t...

  8. Extending the Global Dialogue about Media, Technology, Screen Time, and Young Children

    Science.gov (United States)

    Ernest, James M.; Causey, Cora; Newton, Allison B.; Sharkins, Kimberly; Summerlin, Jennifer; Albaiz, Najla

    2014-01-01

    Questions about the potential benefits and dangers of media and technology use abound, with competing theories regarding its effects among young children. This article explores global perspectives on children's exposure to media, technology, and screen time (MeTS) in the schools, homes, and communities of an increasingly technology-driven…

  9. [Research on the Screening Method of Soil Remediation Technology at Contaminated Sites and Its Application].

    Science.gov (United States)

    Bai, Li-ping; Luo, Yun; Liu, Li; Zhou, You-ya; Yan, Zeng-guang; Li, Fa-sheng

    2015-11-01

    Soil remediation technology screening is an important procedure in the supervision of contaminated sites. The efficiency and costs of contaminated site remediation will be directly affected by the applicability of soil remediation technology. The influencing factors include characteristics of contaminants, site conditions, remediation time and costs should be considered to determine the most applicable remediation technology. The remediation technology screening was commonly evaluated by the experienced expert in China, which limited the promotion and application of the decision making method. Based on the supervision requirements of contaminated sites and the research status at home and abroad, the screening method includes preliminary screening and explicit evaluation was suggested in this paper. The screening index system was constructed, and the extension theory was used to divide the technology grade. The extension theory could solve the problem of human interference in the evaluation process and index value assignment. A chromium residue contaminated site in China was selected as the study area, and the applicable remediation technologies were suggested by the screening method. The research results could provide a scientific and technological support for the supervision and management of contaminated sites in China. PMID:26911012

  10. Skins\\screens\\circuits: how technology remade the body

    OpenAIRE

    Kinsey, C. E. C.

    2012-01-01

    This thesis is an analysis of the social, political and historical inter-relationships between moving image technologies, constructions of gender and sexuality, and theories of science and technology. Presented as a series of case-studies on film, video, medical imaging and computer technology in the work of five women artists, this thesis looks at the way in which artistic practice overturns traditional theories of technology as purely ‘instrumental’, theories of the subject in which identit...

  11. Quantum Feedback Amplification

    Science.gov (United States)

    Yamamoto, Naoki

    2016-04-01

    Quantum amplification is essential for various quantum technologies such as communication and weak-signal detection. However, its practical use is still limited due to inevitable device fragility that brings about distortion in the output signal or state. This paper presents a general theory that solves this critical issue. The key idea is simple and easy to implement: just a passive feedback of the amplifier's auxiliary mode, which is usually thrown away. In fact, this scheme makes the controlled amplifier significantly robust, and furthermore it realizes the minimum-noise amplification even under realistic imperfections. Hence, the presented theory enables the quantum amplification to be implemented at a practical level. Also, a nondegenerate parametric amplifier subjected to a special detuning is proposed to show that, additionally, it has a broadband nature.

  12. High throughput miniature drug-screening platform using bioprinting technology

    International Nuclear Information System (INIS)

    In the pharmaceutical industry, new drugs are tested to find appropriate compounds for therapeutic purposes for contemporary diseases. Unfortunately, novel compounds emerge at expensive prices and current target evaluation processes have limited throughput, thus leading to an increase of cost and time for drug development. This work shows the development of the novel inkjet-based deposition method for assembling a miniature drug-screening platform, which can realistically and inexpensively evaluate biochemical reactions in a picoliter-scale volume at a high speed rate. As proof of concept, applying a modified Hewlett Packard model 5360 compact disc printer, green fluorescent protein expressing Escherichia coli cells along with alginate gel solution have been arrayed on a coverslip chip under a repeatable volume of 180% ± 26% picoliters per droplet; subsequently, different antibiotic droplets were patterned on the spots of cells to evaluate the inhibition of bacteria for antibiotic screening. The proposed platform was compared to the current screening process, validating its effectiveness. The viability and basic function of the printed cells were evaluated, resulting in cell viability above 98% and insignificant or no DNA damage to human kidney cells transfected. Based on the reduction of investment and compound volume used by this platform, this technique has the potential to improve the actual drug discovery process at its target evaluation stage. (paper)

  13. Development and Implementation of High School Chemistry Modules Using Touch-Screen Technologies

    Science.gov (United States)

    Lewis, Maurica S.; Zhao, Jinhui; Montclare, Jin Kim

    2012-01-01

    Technology was employed to motivate and captivate students while enriching their in-class education. An outreach program is described that involved college mentors introducing touch-screen technology into a high school chemistry classroom. Three modules were developed, with two of them specifically tailored to encourage comprehension of molecular…

  14. Technological features of application of nanophotonic elements of packaging by screen printing

    OpenAIRE

    Сарапулова, Ольга Олександрівна; Шерстюк, Валентин Петрович

    2013-01-01

    The technological parameters that affect the process of producing printed packaging with nanophotonic elements were defined. The factors and parameters of manufacturing coatings based on nanosized zinc oxide with photoluminescent properties for producing active and intelligent (smart) packaging by screen printing were studied. The formation of luminescent coatings by screen printing on polypropylene films was carried out and parameters of deposition process and photoluminescence properties of...

  15. A public health response to emerging technology: expansion of the Massachusetts newborn screening program.

    OpenAIRE

    Atkinson, K.; Zuckerman, B.; Sharfstein, J. M.; Levin, D.; Blatt, R. J.; Koh, H. K.

    2001-01-01

    The development of a new technology, called tandem mass spectrometry (tandem MS), has challenged governments worldwide to consider expanding universal newborn screening for rare metabolic disorders. In 1997 the Massachusetts Department of Public Health developed a public process to meet this challenge. After addressing significant medical, legal, ethical, and logistical issues raised by tandem MS, Massachusetts incorporated one new disorder into the mandatory newborn screen and developed an o...

  16. Affinity-Based Screening Technology and HCV Drug Discovery

    Institute of Scientific and Technical Information of China (English)

    LI Bin

    2003-01-01

    @@ NS5A is one of the non-structural gene products encoded by Hepatitis C virus (HCV) and related viruses that are essential for viral replication. The amino acid sequence of NS5A is conserved between different HCV genotypes and the primary amino acid sequence of NS5A is unique to HCV and closely related viruses. Importantly, NS5A is unrelated to any human protein. This indicates that drugs designed to block the actions of NS5A could inhibit the replication of HCV without showing toxic side effects in human host cells, thus making NS5A inhibitors ideal anti-viral drugs. However, there are presently no functional assays for this essential viral protein. Therefore, conventional high throughput screening (HTS) approaches can not be used to discover antiviral drugs against NS5A.

  17. Microfluidics: an enabling screening technology for enhanced oil recovery (EOR).

    Science.gov (United States)

    Lifton, Victor A

    2016-05-21

    Oil production is a critical industrial process that affects the entire world population and any improvements in its efficiency while reducing its environmental impact are of utmost societal importance. The paper reviews recent applications of microfluidics and microtechnology to study processes of oil extraction and recovery. It shows that microfluidic devices can be useful tools in investigation and visualization of such processes used in the oil & gas industry as fluid propagation, flooding, fracturing, emulsification and many others. Critical macro-scale processes that define oil extraction and recovery are controlled by the micro-scale processes based on wetting, adhesion, surface tension, colloids and other concepts of microfluidics. A growing number of research efforts demonstrates that microfluidics is becoming, albeit slowly, an accepted methodology in this area. We propose several areas of development where implementation of microfluidics may bring about deeper understanding and hence better control over the processes of oil recovery based on fluid propagation, droplet generation, wettability control. Studies of processes such as hydraulic fracturing, sand particle propagation in porous networks, high throughput screening of chemicals (for example, emulsifiers and surfactants) in microfluidic devices that simulate oil reservoirs are proposed to improve our understanding of these complicated physico-chemical systems. We also discuss why methods of additive manufacturing (3D printing) should be evaluated for quick prototyping and modification of the three-dimensional structures replicating natural oil-bearing rock formations for studies accessible to a wider audience of researchers. PMID:27087065

  18. THE CLONING OF HRNT-1 USING A COMBINATION OF cDNA LIBRARY SCREENING WITH BIOTIN-LABELED PROBE AND RAPID AMPLIFICATION OF cDNA ENDS

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Kai-tai

    2001-01-01

    [1]Tom S, Andrew PR. Human Molecular Genetics [M]. John Wiley & Sons, Inc. United States of America 1996; 335.[2]Zhao Yong-liang, Jin Cui-zhen, Wu De-chang et al. Neoplastic transformation and cytogenetic changes of rat tracheal epithelial cells induced by a-particles irradiation [J]. Chin Med Sci J 1997; 12:202.[3]Frohman MA. Rapid amplification of complementary DNA ends for generation of full-length complementary DNAs: thermal RACE [J]. Methods Enzymol 1993; 218:340.[4]Frederick A, Roger B. Current Protocols in Molecular Biology [M]. John Wiley & Sons, Inc. United States of America 1998; 2.1.1.[5]Roux KH. Optimization and troubleshooting in PCR [J]. PCR Methods Appl 1995; 4:5158.[6]Sambrook, J, Fritsch EF, Maniatis T. Molecular Cloning: A Laboratory Manual [M]. 2nd Ed. New York: Cold Spring Harbor Laboratory, Cold Spring Harbor, 1989; 54.[7]Zhang Y, Frohman MA. Using rapid amplification of cDNA ends (RACE) to obtain full-length cDNAs [J]. Methods Mol Biol 1997; 69:61.[8]Frohman MA. Rapid amplification of complementary DNA ends for generation of full-length complementary DNAs: thermal RACE [J]. Methods Enzymol 1993; 218:340.[9]Iqbal S, Robinson J, Deere D, et al. Efficiency of the polymerase chain reaction amplification of the uid gene for detection of Escherichia coli in contaminated water [J]. Lett Appl Microbiol 1997; 24:498.[10]Schunck B, Kraft W, Truyen U. A simple touch-down polymerase chain reaction for the detection of canine parvovirus and feline panleukopenia virus in feces [J]. J Virol Methods 1995; 55:427.

  19. Cervical cancer screening in developing countries at a crossroad: Emerging technologies and policy choices.

    Science.gov (United States)

    Catarino, Rosa; Petignat, Patrick; Dongui, Gabriel; Vassilakos, Pierre

    2015-12-10

    Cervical cancer (CC) represents the fourth most common malignancy affecting women all over the world and is the second most common in developing areas. In these areas, the burden from disease remains important because of the difficulty in implementing cytology-based screening programmes. The main obstacles inherent to these countries are poverty and a lack of healthcare infrastructures and trained practitioners. With the availability of new technologies, researchers have attempted to find new strategies that are adapted to low- and middle-income countries (LMIC) to promote early diagnosis of cervical pathology. Current evidence suggests that human papillomavirus (HPV) testing is more effective than cytology for CC screening. Therefore, highly sensitive tests have now been developed for primary screening. Rapid molecular methods for detecting HPV DNA have only recently been commercially available. This constitutes a milestone in CC screening in low-resource settings because it may help overcome the great majority of obstacles inherent to previous screening programmes. Despite several advantages, HPV-based screening has a low positive predictive value for CC, so that HPV-positive women need to be triaged with further testing to determine optimal management. Visual inspection tests, cytology and novel biomarkers are some options. In this review, we provide an overview of current and emerging screening approaches for CC. In particular, we discuss the challenge of implementing an efficient cervical screening adapted to LMIC and the opportunity to introduce primary HPV-based screening with the availability of point-of-care (POC) HPV testing. The most adapted screening strategy to LMIC is still a work in progress, but we have reasons to believe that POC HPV testing makes part of the future strategies in association with a triage test that still needs to be defined. PMID:26677441

  20. INEEL Subsurface Disposal Area CERCLA-based Decision Analysis for Technology Screening and Remedial Alternative Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Parnell, G. S.; Kloeber, Jr. J.; Westphal, D; Fung, V.; Richardson, John Grant

    2000-03-01

    A CERCLA-based decision analysis methodology for alternative evaluation and technology screening has been developed for application at the Idaho National Engineering and Environmental Laboratory WAG 7 OU13/14 Subsurface Disposal Area (SDA). Quantitative value functions derived from CERCLA balancing criteria in cooperation with State and Federal regulators are presented. A weighted criteria hierarchy is also summarized that relates individual value function numerical values to an overall score for a specific technology alternative.

  1. Screening colonoscopy: should we focus more on technique and less on technology?

    OpenAIRE

    Mohammed, Noor; Subramanian, Venkataraman

    2013-01-01

    Several large studies have confirmed that high quality colonoscopic surveillance can improve outcomes with substantial reduction in colorectal cancer rates. In order to improve outcomes from screening colonoscopy and help detect adenomas, the emphasis has been mainly on improvements in technology like high-resolution scopes, computerized as well as dye-based chromoendoscopy and wide-angle endoscopes. In addition to the equipment and technological innovation in the equipment used, a number of ...

  2. Simple solution : VAC-Screen technology helps drillers recapture oil-based mud

    Energy Technology Data Exchange (ETDEWEB)

    Wells, P.

    2010-11-15

    Calgary-based FP Marangoni Inc. has developed a VAC-Screen drilling fluid recovery system that improves the efficiency and environmental performance of oil production operations. With 8 patents filed, FP Marangoni is currently the only oilfield service company in the world that has successfully established a way to blend vacuum and rig shakers to recapture oil-based mud, or any drilling fluid. The VAC-Screen system is now being used by many operators and has the potential to be used across a wide spectrum of drilling applications. The system gives operators a considerable advantage in meeting progressively more stringent environmental regulations for cuttings disposal. The genesis for the system began while the company was working in the Alberta Foothills and a client was losing drilling fluids off of the ends of shakers. A rotary vacuum dryer fluid recovery and cuttings drying system was ruled out for solving the problem because it would degrade the drilling cuttings. FP Marangoni initially opted for blowing mud through the shaker screen using compressed air and air knife drying systems, but the high velocity air created a fine mud mist which created a health hazard. FP Marangoni then opted to build a vacuum manifold, placed it underneath the shaker screen and attached it to the rig vacuum. This method dried the cuttings as hoped, but they froze right on the shaker screen. These issues were sorted out with some fine-tuning and the company was eventually able to run the VAC-Screen technology on any size of shaker screen. The fluid that comes out of the end of the shaker flows onto the vacuum manifolds where it is then recovered and the cuttings dry out. The newly-created design incorporates a processing area which ensures the cuttings are dried out efficiently and are easy to dispose of. A prototype VAC-Screen was run over a three-month period from February through April 2010, and the technology was commercially introduced in June 2010. The VAC-Screen technology is

  3. Identification and complete genome sequencing of paramyxoviruses in mallard ducks (Anas platyrhynchos using random access amplification and next generation sequencing technologies

    Directory of Open Access Journals (Sweden)

    van den Berg Thierry

    2011-10-01

    Full Text Available Abstract Background During a wildlife screening program for avian influenza A viruses (AIV and avian paramyxoviruses (APMV in Belgium, we isolated two hemagglutinating agents from pools of cloacal swabs of wild mallards (Anas platyrhynchos caught in a single sampling site at two different times. AIV and APMV1 were excluded using hemagglutination inhibition (HI testing and specific real-time RT-PCR tests. Methods To refine the virological identification of APMV2-10 realized by HI subtyping tests and in lack of validated molecular tests for APMV2-10, random access amplification was used in combination with next generation sequencing for the sequence independent identification of the viruses and the determination of their genomes. Results Three different APMVs were identified. From one pooled sample, the complete genome sequence (15054 nucleotides of an APMV4 was assembled from the random sequences. From the second pooled sample, the nearly complete genome sequence of an APMV6 (genome size of 16236 nucleotides was determined, as well as a partial sequence for an APMV4. This APMV4 was closely related but not identical to the APMV4 isolated from the first sample. Although a cross-reactivity with other APMV subtypes did not allow formal identification, the HI subtyping revealed APMV4 and APMV6 in the respective pooled samples but failed to identify the co-infecting APMV4 in the APMV6 infected pool. Conclusions These data further contribute to the knowledge about the genetic diversity within the serotypes APMV4 and 6, and confirm the limited sensitivity of the HI subtyping test. Moreover, this study demonstrates the value of a random access nucleic acid amplification method in combination with massive parallel sequencing. Using only a moderate and economical sequencing effort, the characterization and full genome sequencing of APMVs can be obtained, including the identification of viruses in mixed infections.

  4. Intrachromosomal amplification of chromosome 21 (iAMP21 detected by ETV6/RUNX1 FISH screening in childhood acute lymphoblastic leukemia: a case report

    Directory of Open Access Journals (Sweden)

    Daniela Ribeiro Ney Garcia

    2013-01-01

    Full Text Available Chromosome abnormalities that usually define high-risk acute lymphoblastic leukemia are the t(9;22/ breakpoint cluster region protein-Abelson murine leukemia viral oncogene homolog 1, hypodiploid with < 44 chromosomes and 11q23/ myeloid/lymphoid leukemia gene rearrangements. The spectrum of acute lymphoblastic leukemia genetic abnormalities is nevertheless rapidly expanding. Therefore, newly described chromosomal aberrations are likely to have an impact on clinical care in the near future. Recently, the rare intrachromosomal amplification of chromosome 21 started to be considered a high-risk chromosomal abnormality. It occurs in approximately 2-5% of pediatric patients with B-cell precursor acute lymphoblastic leukemia. This abnormality is associated with a poor outcome. Hence, an accurate detection of this abnormality is expected to become very important in the choice of appropriate therapy. In this work the clinical and molecular cytogenetic evaluation by fluorescence in situ hybridization of a child with B-cell precursor acute lymphoblastic leukemia presenting the rare intrachromosomal amplification of chromosome 21 is described.

  5. Rigorous Screening Technology for Identifying Suitable CO2 Storage Sites II

    Energy Technology Data Exchange (ETDEWEB)

    George J. Koperna Jr.; Vello A. Kuuskraa; David E. Riestenberg; Aiysha Sultana; Tyler Van Leeuwen

    2009-06-01

    This report serves as the final technical report and users manual for the 'Rigorous Screening Technology for Identifying Suitable CO2 Storage Sites II SBIR project. Advanced Resources International has developed a screening tool by which users can technically screen, assess the storage capacity and quantify the costs of CO2 storage in four types of CO2 storage reservoirs. These include CO2-enhanced oil recovery reservoirs, depleted oil and gas fields (non-enhanced oil recovery candidates), deep coal seems that are amenable to CO2-enhanced methane recovery, and saline reservoirs. The screening function assessed whether the reservoir could likely serve as a safe, long-term CO2 storage reservoir. The storage capacity assessment uses rigorous reservoir simulation models to determine the timing, ultimate storage capacity, and potential for enhanced hydrocarbon recovery. Finally, the economic assessment function determines both the field-level and pipeline (transportation) costs for CO2 sequestration in a given reservoir. The screening tool has been peer reviewed at an Electrical Power Research Institute (EPRI) technical meeting in March 2009. A number of useful observations and recommendations emerged from the Workshop on the costs of CO2 transport and storage that could be readily incorporated into a commercial version of the Screening Tool in a Phase III SBIR.

  6. Genetic screens and functional genomics using CRISPR/Cas9 technology.

    Science.gov (United States)

    Hartenian, Ella; Doench, John G

    2015-04-01

    Functional genomics attempts to understand the genome by perturbing the flow of information from DNA to RNA to protein, in order to learn how gene dysfunction leads to disease. CRISPR/Cas9 technology is the newest tool in the geneticist's toolbox, allowing researchers to edit DNA with unprecedented ease, speed and accuracy, and representing a novel means to perform genome-wide genetic screens to discover gene function. In this review, we first summarize the discovery and characterization of CRISPR/Cas9, and then compare it to other genome engineering technologies. We discuss its initial use in screening applications, with a focus on optimizing on-target activity and minimizing off-target effects. Finally, we comment on future challenges and opportunities afforded by this technology. PMID:25728500

  7. Developments and the preliminary tests of Resistive GEMs manufactured by a screen printing technology

    CERN Document Server

    Agócs, G; Oliveira, R; Martinego, P; Peskov, Vladimir; Pietropaolo, P; Picchi, P

    2008-01-01

    We report promising initial results obtained with new resistive-electrode GEM (RETGEM) detectors manufactured, for the first time, using screen printing technology. These new detectors allow one to reach gas gains nearly as high as with ordinary GEM-like detectors with metallic electrodes; however, due to the high resistivity of its electrodes the RETGEM, in contrast to ordinary hole-type detectors, has the advantage of being fully spark protected. We discovered that RETGEMs can operate stably and at high gains in noble gases and in other badly quenched gases, such as mixtures of noble gases with air and in pure air; therefore, a wide range of practical applications, including dosimetry and detection of dangerous gases, is foreseeable. To promote a better understanding of RETGEM technology some comparative studies were completed with metallic-electrode thick GEMs. A primary benefit of these new RETGEMs is that the screen printing technology is easily accessible to many research laboratories. This accessibilit...

  8. Genetic screening technology: ethical issues in access to tests by employers and health insurance committees.

    Science.gov (United States)

    Faden, R R; Kass, N E

    1993-01-01

    Whereas the introduction of new technologies previously has raised the ethical question of who ought to have access to a new procedure or device, genetic testing technology raises the new ethical question of to whom access to a new technology ought to be limited. In this article we discuss the implications of employers and private health insurance companies having access to genetic testing technology. Although there may be legitimate business interests in allowing employers and insurers to conduct genetic screening, there are other valid societal interests in regulating or limiting the use of this technology by third parties. Public policy developed in the area of new genetic technology must reflect such interests. PMID:17165239

  9. Introduction and Application of Electrochemical Sensors Based on Screen-Printed Technology

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ We report here the development of chemical sensors based on screen-printed technology in our research group to solve major analytical problems in environmental and clinical aspects. The purpose of the research is aimed at the enhancement of selectivity and sensitivity for analysis and monitoring of pollutants and analytes using novel chenically modified screen-printed electrodes. For example, an enzyme reactor coupled with a copper-plated screen-printed carbon electrode (CuSPE) was developed for glucose sensing. The electrocatalytic reduction of enzymatically produced H2O2 at the CuSPE was determined by flow injection analysis (FIA) in pH 7.4 PBS. The proposed method was applied to determine glucose content in fruit juice and clinical sample and satisfactory results with good recoveries were obtained. A thoroughly kinetics and mechanism study was also done for those systems that are verified in analytical applications.

  10. Introduction and Application of Electrochemical Sensors Based on Screen-Printed Technology

    Institute of Scientific and Technical Information of China (English)

    ZEN; Jyh-Myng

    2001-01-01

    We report here the development of chemical sensors based on screen-printed technology in our research group to solve major analytical problems in environmental and clinical aspects. The purpose of the research is aimed at the enhancement of selectivity and sensitivity for analysis and monitoring of pollutants and analytes using novel chenically modified screen-printed electrodes. For example, an enzyme reactor coupled with a copper-plated screen-printed carbon electrode (CuSPE) was developed for glucose sensing. The electrocatalytic reduction of enzymatically produced H2O2 at the CuSPE was determined by flow injection analysis (FIA) in pH 7.4 PBS. The proposed method was applied to determine glucose content in fruit juice and clinical sample and satisfactory results with good recoveries were obtained. A thoroughly kinetics and mechanism study was also done for those systems that are verified in analytical applications.  ……

  11. Cost-Effectiveness of Old and New Technologies for Aneuploidy Screening.

    Science.gov (United States)

    Sinkey, Rachel G; Odibo, Anthony O

    2016-06-01

    Cost-effectiveness analyses allow assessment of whether marginal gains from new technology are worth increased costs. Several studies have examined cost-effectiveness of Down syndrome (DS) screening and found it to be cost-effective. Noninvasive prenatal screening also appears to be cost-effective among high-risk women with respect to DS screening, but not for the general population. Chromosomal microarray (CMA) is a genetic sequencing method superior to but more expensive than karyotype. In light of CMAs greater ability to detect genetic abnormalities, it is cost-effective when used for prenatal diagnosis of an anomalous fetus. This article covers methodology and salient issues of cost-effectiveness. PMID:27235909

  12. Cost comparison of laboratory methods and four field screening technologies for uranium-contaminated soil

    International Nuclear Information System (INIS)

    To address the problem of characterizing uranium-contaminated surface soil at federal facilities, the Department of Energy has the development of four uranium field screening technologies, under the direction of the Uranium-in-Soils Integrated Demonstration (USID) Program. These four technologies include: a long-range alpha detector a beta scintillation detector, an in situ gamma detector, and a mobile laser ablation-inductively coupled plasma/atomic emission spectrometry (LA-ICP/AES) laboratory. As part of the performance assessment for these field screening technologies, cost estimates for the development and operation of each technology were created. A cost study was conducted to compare three of the USID field screening technologies to the use of traditional field surveying equipment to adequately characterize surface soils of a one-acre site. The results indicate that the use of traditional equipment costs more than the in situ gamma detector, but less than the beta scintillation detector and LRAD. The use of traditional field surveying equipment results in cost savings of 4% and 34% over the use of the beta scintillation and LRAD technologies, respectively. A study of single-point surface soil sampling and laboratory analysis costs was also conducted. Operational costs of the mobile LA-ICP/AES laboratory were compared with operational costs of traditional sampling and analysis, which consists of collecting soil samples and conducting analysis in a radiochemical laboratory. The cost study indicates that the use of the mobile LA-ICP/AES laboratory results in cost savings of 23% and 40% over traditional field sampling and laboratory analysis conducted by characterization groups at two DOE facilities

  13. Awareness, Interest, and Preferences of Primary Care Providers in Using Point-of-Care Cancer Screening Technology

    OpenAIRE

    Kim, Chloe S.; Vanture, Sarah; Cho, Margaret; Klapperich, Catherine M.; Wang, Catharine; Huang, Franklin W.

    2016-01-01

    Well-developed point-of-care (POC) cancer screening tools have the potential to provide better cancer care to patients in both developed and developing countries. However, new medical technology will not be adopted by medical providers unless it addresses a population’s existing needs and end-users’ preferences. The goals of our study were to assess primary care providers’ level of awareness, interest, and preferences in using POC cancer screening technology in their practice and to provide g...

  14. Impact of technology on cytology outcome in cervical cancer screening of young and older women

    DEFF Research Database (Denmark)

    Møller, Johanne Cecilie Rask; Lynge, Elsebeth; Franzmann, Maria;

    2014-01-01

    Little is known about age-dependent variation in outcomes of cervical cytology with modern technologies. This population-based study evaluated age-dependent changes after routine implementation of ThinPrep and SurePath technology in two independent laboratories, and controlled for time trends in ...... unchanged technology no trends in abnormality proportions were observed. The impact of LBC implementation on cytological abnormality proportions varied considerably across age groups.......Little is known about age-dependent variation in outcomes of cervical cytology with modern technologies. This population-based study evaluated age-dependent changes after routine implementation of ThinPrep and SurePath technology in two independent laboratories, and controlled for time trends in a...... technology phase. The study included 489,960 cytological samples with no recent abnormality from women aged 23-59 years, routinely screened between 1998 and 2007. Implementation of SurePath liquid-based cytology (LBC) was followed by an increase in abnormal cytology in women aged 23-29 years from 4.6 to 6...

  15. Advances in Tumor Screening, Imaging, and Avatar Technologies for High-Grade Serous Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Anders eOhman

    2014-11-01

    Full Text Available The majority of high-grade serous ovarian carcinoma cases are detected in advanced stages when treatment options are limited. Surgery is less effective at eradicating the disease when it is widespread, resulting in high rates of disease relapse and chemoresistance. Current screening techniques are ineffective for early tumor detection and consequently, BRCA mutations carriers, with an increased risk for developing high-grade serous ovarian cancer, elect to undergo risk-reducing surgery. While prophylactic surgery is associated with a significant reduction in the risk of cancer development, it also results in surgical menopause and significant adverse side effects. The development of efficient early-stage screening protocols and imaging technologies is critical to improving the outcome and quality of life for current patients and women at increased risk. In addition, more accurate animal models are necessary in order to provide relevant in vivo testing systems and advance our understanding of the disease origin and progression. Moreover, both genetically engineered and tumor xenograft animal models enable the preclinical testing of novel imaging techniques and molecularly targeted therapies as they become available. Recent advances in xenograft technologies have made possible the creation of avatar mice, personalized tumorgrafts, which can be used as therapy testing surrogates for individual patients prior to or during treatment. High-grade serous ovarian cancer may be an ideal candidate for use with avatar models based on key characteristics of the tumorgraft platform. This review explores multiple strategies, including novel imaging and screening technologies in both patients and animal models, aimed at detecting cancer in the early stages and improving the disease prognosis.

  16. Theoretical Screening of Mixed Solid Sorbent for Applications to CO{sub 2} Capture Technology

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Yuhua

    2014-03-30

    Since current technologies for capturing CO{sub 2} to fight global climate change are still too energy intensive, there is a critical need for development of new materials that can capture CO{sub 2} reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO{sub 2} capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO{sub 2} sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculated thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO{sub 2} adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO{sub 2} capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. Only those selected CO{sub 2} sorbent candidates were further considered for experimental validations. The ab initio thermodynamic technique has the advantage of identifying thermodynamic properties of CO{sub 2} capture reactions without any experimental input beyond crystallographic structural information of the solid phases involved. Such methodology not only can be used to search for good candidates from existing database of solid materials, but also can provide some guidelines for synthesis new materials. In this presentation, we apply our screening methodology to mixing solid systems to adjust the turnover temperature to help on developing CO{sub 2} capture Technologies.

  17. Theoretical Screening of Mixed Solid Sorbent for Applications to CO2 Capture Technology

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Yuhua

    2014-01-01

    Since current technologies for capturing CO2 to fight global climate change are still too energy intensive, there is a critical need for development of new materials that can capture CO2 reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO2 capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO2 sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculated thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO2 adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO2 capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. Only those selected CO2 sorbent candidates were further considered for experimental validations. The ab initio thermodynamic technique has the advantage of identifying thermodynamic properties of CO2 capture reactions without any experimental input beyond crystallographic structural information of the solid phases involved. Such methodology not only can be used to search for good candidates from existing database of solid materials, but also can provide some guidelines for synthesis new materials. In this presentation, we apply our screening methodology to mixing solid systems to adjust the turnover temperature to help on developing CO2 capture Technologies.

  18. Label-free screening of single biomolecules through resistive pulse sensing technology for precision medicine applications

    Science.gov (United States)

    Harrer, S.; Kim, S. C.; Schieber, C.; Kannam, S.; Gunn, N.; Moore, S.; Scott, D.; Bathgate, R.; Skafidas, S.; Wagner, J. M.

    2015-05-01

    Employing integrated nano- and microfluidic circuits for detecting and characterizing biological compounds through resistive pulse sensing technology is a vibrant area of research at the interface of biotechnology and nanotechnology. Resistive pulse sensing platforms can be customized to study virtually any particle of choice which can be threaded through a fluidic channel and enable label-free single-particle interrogation with the primary read-out signal being an electric current fingerprint. The ability to perform label-free molecular screening with single-molecule and even single binding site resolution makes resistive pulse sensing technology a powerful tool for analyzing the smallest units of biological systems and how they interact with each other on a molecular level. This task is at the core of experimental systems biology and in particular ‘omics research which in combination with next-generation DNA-sequencing and next-generation drug discovery and design forms the foundation of a novel disruptive medical paradigm commonly referred to as personalized medicine or precision medicine. DNA-sequencing has approached the 1000-Dollar-Genome milestone allowing for decoding a complete human genome with unmatched speed and at low cost. Increased sequencing efficiency yields massive amounts of genomic data. Analyzing this data in combination with medical and biometric health data eventually enables understanding the pathways from individual genes to physiological functions. Access to this information triggers fundamental questions for doctors and patients alike: what are the chances of an outbreak for a specific disease? Can individual risks be managed and if so how? Which drugs are available and how should they be applied? Could a new drug be tailored to an individual’s genetic predisposition fast and in an affordable way? In order to provide answers and real-life value to patients, the rapid evolvement of novel computing approaches for analyzing big data in

  19. Trialling computer touch-screen technology to assess psychological distress in patients with gynaecological cancer

    Directory of Open Access Journals (Sweden)

    Georgia Halkett

    2010-12-01

    Full Text Available BackgroundCancer impacts on the psychological well-being of many cancer patients. Appropriate tools can be used to assist health professionals in identifying patient needs and psychological distress. Recent research suggests that touchscreen technology can be used to administer surveys. The aim of this study was to evaluate the use of a touchscreen system in comparison to written questionnaires in a large tertiary hospital in Western Australia (WA.Method Patients who were scheduled to commence treatment for gynaecological cancer participated in this study. Patients were assigned to complete either a written questionnaire or the same survey using the touchscreen technology. Both methods of survey contained the same scales. All participants were asked to complete a follow-up patient satisfaction survey. Semi-structured interviews were conducted with health professionals to elicit views about the implementation of the technology and the available referral pathways. Data was analysed using descriptive statistics and content analysis. ResultsThirty patients completed the touchscreen questionnaires and an equal number completed the survey on paper. Participants who used the touchscreens were not significantly more satisfied than other participants. Four themes were noted in the interviews with health professionals: usability of technology, patients’ acceptance of technology, advantages of psychological screening and the value of the instruments included.ConclusionAlthough previous studies report that computerised assessments are a feasible option for assessing cancer patients’ needs, the data collected in this study demonstrates that the technology was not reliable with significant practical problems. The technology did not serve these patients better than pen and paper.

  20. BIG BROTHER IS WATCHING YOU! TO BE OR NOT TO BE ONLINE... OR SCREEN AS OUR OWN TECHNOLOGICAL ADDRESS

    Directory of Open Access Journals (Sweden)

    Vanda Maria Sousa

    2014-12-01

    Full Text Available This article seeks to answer the question: how the screens are interposed between the subject and reality, in contexts of the New Technologies of Information and Communication, particularly in the case of television screens (in the reality show format and computer screens (by the profusion of social networks? Using the interpretative methodology, our goal is to take as a starting point the etymology of technic and technology to establish the technological nature of man’s relationship with reality. Once this premise is demonstrated, we will convene the Heideggerian concepts (dasein and ge-stell to interpret how the technology of the screen meets a social need for happiness that comes from the media in a world that re-discovers itself as iconic. Each of us is called upon, in our day-to-day life, to an important, special and urgent meeting with the representation of our own selves, against a screen, where will be its own place of happiness. We intend to assess whether ideologies are hiper-evaluated today, especially when translating reality into binary conceptions of the world, projecting dasein on the demand for unity (1, opposing it to failure (0, each time using the screen more like a mirror or a window, and forgetting its function as a ge-stell by making it a promotion, and not doing it as a way to discover dasein, but, instead, as the opening of the simulacra itself.

  1. 基于辣根过氧化物酶放大的丝网印刷电极DNA传感器%A Screen-printed Electrode DNA Sensor Based on Horseradish Peroxidase-catalysed Amplification

    Institute of Scientific and Technical Information of China (English)

    邹元明; 冷翠翠; 万钧

    2011-01-01

    以聚苯胺纳米管、壳聚糖、室温离子液体修饰的丝网印刷电极为基底电极,以辣根过氧化物酶(HRP)催化的H2O2氧化邻苯二胺(OPD)的反应作为信号放大手段,构建了一个酶放大丝网印刷DNA传感器.考察并确定了在修饰丝网印刷电极上,上述反应的最优条件及进行电化学测定的最优条件:HRP催化OPD与H2O2反应的最佳缓冲液为pH5.0的醋酸-醋酸钠缓冲液;最佳检测支持电解质为pH 7.2的PBS缓冲液.HRP催化OPD与双氧水反应的最佳反应条件:使用16 mmol·L-1双氧水和30 mmol·L-1OPD反应15 min.在该传感器上,在最优条件下,DNA测定的线性范围为2×10-14mol·L-1到8×10-13 mol·L-1,回归方程为Δip=0.3086+0.016 0 cΥ.通过3σ规则计算出的DNA检测限为8×10-15 mol·L-1.该传感器在DNA检测方面具有良好的选择性.%In this study, a DNA sensor was constructed based on the screen-printed electrode that was modified with polyaniline nanotubes, chitosan and room-temperature ionic liquids, and by using the horseradish peroxidase catalyzed oxidation of H2 O2 to o-phenenyldiamine (OPD) as the signal amplification approach. The optimal conditions for the above-mentioned reaction and for the electrochemical determination on the modified screen-printed electrode were established as follows: the optimal buffer for the HRP-catalyzed oxidation of OPD by H2O2 was HOAc-NaOAc at pH 5. 0; the optimal buffer for the electrochemical determination was PBS at pH 7. 2; the best working condition for HRP-catalyzed oxidation was at a reaction time of 15 min with 16 mmol ? L"1 H2O2 and 30 mmol· L-1 OPD. Under these optimal conditions, DNA can be determined in a linear range from 2×10-14mol· L-1 to 8×10-13 mol· L-1, with a regression equation △iP = 0. 308 6+0. 016 0cT. The detected limit was found to be 8×10-15 mol· L-1 according to 3σ rule. Good selectivity against mismatched DNAs was verified.

  2. 膨胀筛管防砂技术研究%Application of expandable screen pipe technology for sand control

    Institute of Scientific and Technical Information of China (English)

    沈琛; 宁学涛; 朱海波; 唐明

    2011-01-01

    膨胀筛管技术是一种新兴的防砂技术,介绍了大通径膨胀筛管悬挂器、带有割缝的膨胀螺纹及具有变径功能的膨胀工具等膨胀筛管的几个关键技术.大通径膨胀筛管悬挂器能够确保变径膨胀工具的顺利下入,带有割缝的螺纹膨胀后与筛管本体具有一样大小的内径,变径膨胀工具使得膨胀筛管可以紧贴井壁,减少砂粒的运移和冲蚀.膨胀筛管技术在两口套损井中的防砂应用表明,在满足选井条件的情况下,采用膨胀筛管可以获得较好的生产效果,筛管膨胀后紧贴套管内壁,膨胀后筛管内径比普通筛管内径大,有利于增大泄油面积,提高油井产量.%Expandable Screen Technology is a new sand control technique. Expandable hanger with larger diameter, expandable screw with slot and expansion tool with diameter variable features are several key technologies of expandable screen. Expandable hanger with larger diameter enables the diameter variable expansion tool to run into the well successfully, the slotted thread after expansion has the same diameter with expandable screen, and The adjustable expansion tool makes expandable screen close to the wall, which can reduce the migration of sand and erosion. In this paper, the study on the slotted expandable thread, expandable hanger and the development of adjustable expansion tool, ground-based testing and underground simulation testing of expandable screen were introduced. This application of expandable screen technology in two damaged casing for the sand control illustrated that adopting expandable tube can get favorable productivity after meeting the requirement of selecting well condition. The expandable screen touching the inwall of the casing for which the inner diameter of expandable screen is bigger than that of conventional screen pipe, is helpful to enlarge the drainage area and enhance oil well productivity.

  3. Fluorescence imaging technology (FI) for high-throughput screening of selenide-modified nano-TiO2 catalysts.

    Science.gov (United States)

    Wang, Liping; Lee, Jianchao; Zhang, Meijuan; Duan, Qiannan; Zhang, Jiarui; Qi, Hailang

    2016-02-18

    A high-throughput screening (HTS) method based on fluorescence imaging (FI) was implemented to evaluate the catalytic performance of selenide-modified nano-TiO2. Chemical ink-jet printing (IJP) technology was reformed to fabricate a catalyst library comprising 1405 (Ni(a)Cu(b)Cd(c)Ce(d)In(e)Y(f))Se(x)/TiO2 (M6Se/Ti) composite photocatalysts. Nineteen M6Se/Tis were screened out from the 1405 candidates efficiently. PMID:26777131

  4. 大屏幕拼接技术及其应用%Large-Screen Splicing Technology and Its Applications

    Institute of Scientific and Technical Information of China (English)

    卢光义

    2009-01-01

    大屏幕拼接技术是现代计算机图形处理技术和各种显示技术的有机结合,实现多路独立视频信号和计算机信号同时直通显示,单元无级缩放、画中画显示,网络计算机信号快速显示,高分辨率全屏显示,灵活缩放显示、大画面跨屏清晰显示,超高分辨率图像、视频、计算机、网络信号综合显示等.广泛用于部队、武警、公安指挥中心、政府视频会议系统、企业生产调度中心等场合.该文主要介绍DLP、MPDP、LED三种主流大屏幕拼接技术的原理、结构和实际运用.%Splicing technology is a large-screen graphics of modern computer technology and the organic integration of display technology to achieve an independent multi-channel video signal and computer signal through at the same time show that no unit-level zoom, pic-ture-in-picture display, network computer signal quickly revealed that high-resolution the rate of full-screen display, flexible scaling showed that the screen to clearly indicate that cross-screen, ultra-high-resohition images, video, computer, network signal integrated dis-play. Widely used in troops, armed police, public security command center, the Government Video Conference System, business centers, production scheduling occasions. In this paper, DLP, MPDP, LED splicing of three large-screen technology to mainstream the principles, structure and practical appli-cation.

  5. Amplification for the Adolescent.

    Science.gov (United States)

    Wilber, Laura Ann

    1978-01-01

    Explored are various means of amplification for aurally handicapped adolescents, including behind-the-ear hearing aids, "custom ear" (or in-the-ear) hearing aids, as well as aural rehabilitation. (BD)

  6. A virtual test of screening technology based on the AGEIA PhysX

    Energy Technology Data Exchange (ETDEWEB)

    Ai-min Li; Rui-ling Lv; Chu-sheng Liu [China University of Mining and Technology, Xuzhou (China). School of Mechanical and Electrical Engineering

    2008-06-15

    The authors have created a virtual test of vibration particle-screening using Autodesk's 3ds Max software, the MAXScript scripting language and the AGEIA PhysX physics processing unit (PPU). The affect of various parameters on screening efficiency were modeled. The parameters included vibration amplitude, frequency and direction. The length and inclination of the vibrating surface were also varied. The virtual experiment is in basic agreement with results predicted from screening theory. This shows that the virtual screener can be used for preliminary investigations and the results used to evaluate screen design. In addition it can help with theoretical research. 11 refs., 7 figs., 7 tabs.

  7. A virtual test of screening technology based on the AGEIA PhysX

    Institute of Scientific and Technical Information of China (English)

    LI Ai-min; LV Rui-ling; LIU Chu-sheng

    2008-01-01

    The authors have created a virtual test of vibration particle-screening using Autodesk's 3ds Max software, the MAXScript scripting language and the AGEIA PhysX physics processing unit (PPU). The affect of various parameters on screening efficiency were modeled. The parameters included vibration amplitude, frequency and direction. The length and inclination of the vibrating surface were also varied. The virtual experiment is in basic agreement with results predicted from screening theory. This shows that the virtual screener can be used for preliminary investigations and the results used to evaluate screen design. In addition it can help with theoretical research.

  8. Progress of breast cancer screening technology%乳腺癌筛查技术的进展

    Institute of Scientific and Technical Information of China (English)

    蔡卓君

    2016-01-01

    As a main threat to female health, breast cancer has shown increasing morbidity rate in recent years, and it has become an critical public health issue in society. Breast cancer screening is helpful for detecting and preventing breast cancer, and the main screening technology in China include clinical breast check, breast X-ray, breast ultrasounography, breast magnetic resonance imaging, and breast blood oxygen functional imaging. This paper made a comparison of advantages and disadvantages of breast cancer screening technology, so as to provide reference and basis for female breast cancer screening strategy.%乳腺癌是威胁女性健康的主要疾病,近年其发病率呈上升趋势,成为当前社会重大公共卫生问题。乳腺癌筛查有助于发现和预防乳腺癌,国内外目前主要筛查技术有临床乳腺检查、乳腺X 线、乳腺超声、乳腺磁共振成像、乳腺血氧功能成像等,本文对乳腺癌筛查技术的优缺点进行比较,为女性乳腺癌筛查策略提供参考和依据。

  9. PCR technology for screening and quantification of genetically modified organisms (GMOs).

    Science.gov (United States)

    Holst-Jensen, Arne; Rønning, Sissel B; Løvseth, Astrid; Berdal, Knut G

    2003-04-01

    Although PCR technology has obvious limitations, the potentially high degree of sensitivity and specificity explains why it has been the first choice of most analytical laboratories interested in detection of genetically modified (GM) organisms (GMOs) and derived materials. Because the products that laboratories receive for analysis are often processed and refined, the quality and quantity of target analyte (e.g. protein or DNA) frequently challenges the sensitivity of any detection method. Among the currently available methods, PCR methods are generally accepted as the most sensitive and reliable methods for detection of GM-derived material in routine applications. The choice of target sequence motif is the single most important factor controlling the specificity of the PCR method. The target sequence is normally a part of the modified gene construct, for example a promoter, a terminator, a gene, or a junction between two of these elements. However, the elements may originate from wildtype organisms, they may be present in more than one GMO, and their copy number may also vary from one GMO to another. They may even be combined in a similar way in more than one GMO. Thus, the choice of method should fit the purpose. Recent developments include event-specific methods, particularly useful for identification and quantification of GM content. Thresholds for labelling are now in place in many countries including those in the European Union. The success of the labelling schemes is dependent upon the efficiency with which GM-derived material can be detected. We will present an overview of currently available PCR methods for screening and quantification of GM-derived DNA, and discuss their applicability and limitations. In addition, we will discuss some of the major challenges related to determination of the limits of detection (LOD) and quantification (LOQ), and to validation of methods. PMID:12733008

  10. Loop-mediated isothermal amplification as an emerging technology for detection of Yersinia ruckeri the causative agent of enteric red mouth disease in fish

    Directory of Open Access Journals (Sweden)

    Soliman Hatem

    2008-08-01

    Full Text Available Abstract Background Enteric Redmouth (ERM disease also known as Yersiniosis is a contagious disease affecting salmonids, mainly rainbow trout. The causative agent is the gram-negative bacterium Yersinia ruckeri. The disease can be diagnosed by isolation and identification of the causative agent, or detection of the Pathogen using fluorescent antibody tests, ELISA and PCR assays. These diagnostic methods are laborious, time consuming and need well trained personnel. Results A loop-mediated isothermal amplification (LAMP assay was developed and evaluated for detection of Y. ruckeri the etiological agent of enteric red mouth (ERM disease in salmonids. The assay was optimised to amplify the yruI/yruR gene, which encodes Y. ruckeri quorum sensing system, in the presence of a specific primer set and Bst DNA polymerase at an isothermal temperature of 63°C for one hour. Amplification products were detected by visual inspection, agarose gel electrophoresis and by real-time monitoring of turbidity resulted by formation of LAMP amplicons. Digestion with HphI restriction enzyme demonstrated that the amplified product was unique. The specificity of the assay was verified by the absence of amplification products when tested against related bacteria. The assay had 10-fold higher sensitivity compared with conventional PCR and successfully detected Y. ruckeri not only in pure bacterial culture but also in tissue homogenates of infected fish. Conclusion The ERM-LAMP assay represents a practical alternative to the microbiological approach for rapid, sensitive and specific detection of Y. ruckeri in fish farms. The assay is carried out in one hour and needs only a heating block or water bath as laboratory furniture. The advantages of the ERM-LAMP assay make it a promising tool for molecular detection of enteric red mouth disease in fish farms.

  11. Can Coolness Predict Technology Adoption? Effects of Perceived Coolness on User Acceptance of Smartphones with Curved Screens.

    Science.gov (United States)

    Kim, Ki Joon; Shin, Dong-Hee; Park, Eunil

    2015-09-01

    This study proposes an acceptance model for curved-screen smartphones, and explores how the sense of coolness induced by attractiveness, originality, subcultural appeal, and the utility of the curved screen promotes smartphone adoption. The results of structural equation modeling analyses (N = 246) show that these components of coolness (except utility) increase the acceptance of the technology by enhancing the smartphones' affectively driven qualities rather than their utilitarian ones. The proposed coolness model is then compared with the original technology acceptance model to validate that the coolness factors are indeed equally effective determinants of usage intention, as are the extensively studied usability factors such as perceived ease of use and usefulness. PMID:26348813

  12. Exploring screen printing technology on thermoelectric energy harvesting with printing copper-nickel and bismuth-antimony thermocouples

    OpenAIRE

    Cao, Zhuo; Koukharenko, Elena; Torah, R; Beeby, SP

    2013-01-01

    This paper reports the fabrication and testing of copper (Cu) - nickel (Ni) and bismuth (Bi) - antimony (Sb) based thermocouples fabricated using screen printing technology. The transport properties of the printed thermoelectric material were measured in room temperature while the Seebeck voltage and power output of the printed thermocouples were tested under a variety temperature gradient. Initial thermoelectric materials have been integrated in inks and then deposited on substrate by the si...

  13. Ultrasound as an Adjunct to Mammography for Breast Cancer Screening: A Health Technology Assessment

    Science.gov (United States)

    2016-01-01

    Background Screening with mammography can detect breast cancer early, before clinical symptoms appear. Some cancers, however, are not captured with mammography screening alone. Ultrasound has been suggested as a safe adjunct screening tool that can detect breast cancers missed on mammography. We investigated the benefits, harms, cost-effectiveness, and cost burden of ultrasound as an adjunct to mammography compared with mammography alone for screening women at average risk and at high risk for breast cancer. Methods We searched Ovid MEDLINE, Ovid Embase, EBM Reviews, and the NHS Economic Evaluation Database, from January 1998 to June 2015, for evidence of effectiveness, harms, diagnostic accuracy, and cost-effectiveness. Only studies evaluating the use of ultrasound as an adjunct to mammography in the specified populations were included. We also conducted a cost analysis to estimate the costs in Ontario over the next 5 years to fund ultrasound as an adjunct to mammography in breast cancer screening for high-risk women who are contraindicated for MRI, the current standard of care to supplement mammography. Results No studies in average-risk women met the inclusion criteria of the clinical review. We included 5 prospective, paired cohort studies in high-risk women, 4 of which were relevant to the Ontario context. Adjunct ultrasound identified between 2.3 and 5.9 additional breast cancers per 1,000 screens. The average pooled sensitivity of mammography and ultrasound was 53%, a statistically significant increase relative to mammography alone (absolute increase 13%; P mammography screening alone. The GRADE for this body of evidence was low. Additional annual costs of using breast ultrasound as an adjunct to mammography for high-risk women in Ontario contraindicated for MRI would range from $15,500 to $30,250 in the next 5 years. Conclusions We found no evidence that evaluated the comparative effectiveness or diagnostic accuracy of screening breast ultrasound as an

  14. Risk Perception and Social Amplification

    International Nuclear Information System (INIS)

    This paper seeks to consider social amplification as it applies to risk perception. Perceptions of the magnitude of a risk are conditioned by issues such as the degree of uncertainty in probability and consequences, the nature of the consequences and the relative weightings placed on probability and consequences. Risk perceptions are also influenced by factors such as confidence in the operator of an industrial process, trust in the regulator and the perceived fairness of regulatory decision-making. Different people may hold different views about these issues and there may also be difficulties in communication. The paper identifies and discusses self-reinforcing mechanisms, which will be labelled 'lock-in' here. They appear to apply in many situations where social amplification is observed. Historically, the term 'lock-in' has been applied mainly in the technological context but, in this paper, four types of lock-in are identified, namely scientific/technological, economic, social and institutional lock-in. One type of lock-in tends to lead to the next and all are buttressed by people's general acceptance of the familiar, fear of the unknown and resistance to change. The regulator seeks to make decisions which achieve the common good rather than supporting or perpetuating any set of vested interests. In this regard the locked-in positions of stakeholders, whether organisations, interest groups, or individual members of the public, are obstacles and challenges. Existing methods of consultation are unsatisfactory in terms of achieving a proper and productive level of dialogue with stakeholders

  15. Development of a Health Screening Package Under the Universal Health Coverage: The Role of Health Technology Assessment.

    Science.gov (United States)

    Teerawattananon, Yot; Kingkaew, Pritaporn; Koopitakkajorn, Tanunya; Youngkong, Sitaporn; Tritasavit, Nattha; Srisuwan, Patsri; Tantivess, Sripen

    2016-02-01

    This study reports the systematic development of a population-based health screening package for all Thai people under the universal health coverage (UHC). To determine major disease areas and health problems for which health screening could mitigate health burden, a consultation process was conducted in a systematic, participatory, and evidence-based manner that involved 41 stakeholders in a half-day workshop. Twelve diseases/health problems were identified during the discussion. Subsequently, health technology assessments, including systematic review and meta-analysis of health benefits as well as economic evaluations and budget impact analyses of corresponding population-based screening interventions, were completed. The results led to advice against elements of current clinical practice, such as annual chest X-rays and particular blood tests (e.g. kidney function test), and indicated that the introduction of certain new population-based health screening programs, such as for chronic hepatitis B, would provide substantial health and economic benefits to the Thais. The final results were presented to a wide group of stakeholders, including decision-makers at the Ministry of Public Health and the public health insurance schemes, to verify and validate the findings and policy recommendations. The package has been endorsed by the Thai UHC Benefit Package Committee for implementation in fiscal year 2016. PMID:26774008

  16. Preparation of a YAG:Ce phosphor glass by screen-printing technology and its application in LED packaging.

    Science.gov (United States)

    Yang, Liang; Chen, Mingxiang; Lv, Zhicheng; Wang, Simin; Liu, Xiaogang; Liu, Sheng

    2013-07-01

    A simple and practical method for preparing phosphor glass is proposed. Phosphor distribution and element analysis are investigated by optical microscope and field emission scanning electron microscope (FE-SEM). The phosphor particles dispersed in the matrix are vividly observed, and their distributions are uniform. Spectrum distribution and color coordinates dependent on the thickness of the screen-printed phosphor layer coupled with a blue light emitting diode (LED) chip are studied. The luminous efficacy of the 75 μm printed phosphor-layer phosphor glass packaged white LED is 81.24 lm/W at 350 mA. This study opens up many possibilities for applications using the phosphor glass on a selected chip in which emission is well absorbed by all phosphors. The screen-printing technique also offers possibilities for the design and engineering of complex phosphor layers on glass substrates. Phosphor screen-printing technology allows the realization of high stability and thermal conductivity for the phosphor layer. This phosphor glass method provides many possibilities for LED packing, including thin-film flip chip and remote phosphor technology. PMID:23811889

  17. On soliton amplification

    Science.gov (United States)

    Leibovich, S.; Randall, J. D.

    1979-01-01

    The paper considers a modified Korteweg-de Vries equation that permits wave amplification or damping. A 'terminal similarity' solution is identified for large times in amplified systems. Numerical results are given which confirm that the terminal similarity solution is a valid local approximation for mu t sufficiently large and positive, even though the approximation is not uniformly valid in space.

  18. Balanced-PCR amplification allows unbiased identification of genomic copy changes in minute cell and tissue samples

    OpenAIRE

    Wang, Gang; Brennan, Cameron; Rook, Martha; Wolfe, Jia Liu; Leo, Christopher; Chin, Lynda; Pan, Hongjie; Liu, Wei-Hua; Price, Brendan; Makrigiorgos, G. Mike

    2004-01-01

    Analysis of genomic DNA derived from cells and fresh or fixed tissues often requires whole genome amplification prior to microarray screening. Technical hurdles to this process are the introduction of amplification bias and/or the inhibitory effects of formalin fixation on DNA amplification. Here we demonstrate a balanced-PCR procedure that allows unbiased amplification of genomic DNA from fresh or modestly degraded paraffin-embedded DNA samples. Following digestion and ligation of a target a...

  19. A preliminary screening study on the associated proteins in human psoriasis vulgaris by serum proteomics technologies

    Institute of Scientific and Technical Information of China (English)

    Zhankui Liu; Shengshun Tan; Chunshui Yu; Jinghua Fan; Zhuanli Bai; Junjie Li

    2007-01-01

    Objective:To investigate the optimum screening conditions of associated proteins in human psoriasis vulgaris by serum proteomics technique, and to screen the different expression proteins related with psoriasis vulgaris. Methods:Serum samples of peripheral blood were collected from newly diagnosed psoriasis vulgaris patients in the clinic, and 20 matched healthy persons.Serum albumin IgG was removed by filtering with ProteoExtract Albumin/IgG. After comparative proteomics analysis the different protein spots were identified using 2-DE and MS. Results :Electrophoresis figures with high resolution and reproducibility were obtained. Three different expression proteins were found only in the serum from psoriasis vulgaris patients,while nine other different proteins expressing from healthy volunteers. Conclusion:The protein expression was different in the serum between the psoriasis vulgaris patients and healthy volunteers. It was hoped that we could find the biomarkers related to psoriasis vulgaris by using proteomics.

  20. Detergent screening of a GPCR using serial and array biosensor technologies

    OpenAIRE

    Rich, Rebecca L.; Miles, Adam R.; Gale, Bruce K.; Myszka, David G.

    2008-01-01

    We describe the benefits and limitations of two biosensor approaches for screening solubilization conditions for G-protein-coupled receptors. Assays designed for a serially processing instrument (Biacore 2000/3000/T100) and an array platform (Biacore Flexchip) were used to examine how effectively 96 different detergents solubilized the chemokine receptor CCR5 while maintaining its binding activity for a conformationally sensitive Fab (2D7). Using the serial-processing instrument, we were able...

  1. Library design and screening protocol for artificial metalloenzymes based on the biotin-streptavidin technology.

    Science.gov (United States)

    Mallin, Hendrik; Hestericová, Martina; Reuter, Raphael; Ward, Thomas R

    2016-05-01

    Artificial metalloenzymes (ArMs) based on the incorporation of a biotinylated metal cofactor within streptavidin (Sav) combine attractive features of both homogeneous and enzymatic catalysts. To speed up their optimization, we present a streamlined protocol for the design, expression, partial purification and screening of Sav libraries. Twenty-eight positions have been subjected to mutagenesis to yield 335 Sav isoforms, which can be expressed in 24-deep-well plates using autoinduction medium. The resulting cell-free extracts (CFEs) typically contain >1 mg of soluble Sav. Two straightforward alternatives are presented, which allow the screening of ArMs using CFEs containing Sav. To produce an artificial transfer hydrogenase, Sav is coupled to a biotinylated three-legged iridium pianostool complex Cp*Ir(Biot-p-L)Cl (the cofactor). To screen Sav variants for this application, you would determine the number of free binding sites, treat them with diamide, incubate them with the cofactor and then perform the reaction with your test compound (the example used in this protocol is 1-phenyl-3,4-dihydroisoquinoline). This process takes 20 d. If you want to perform metathesis reactions, Sav is coupled to a biotinylated second-generation Grubbs-Hoveyda catalyst. In this application, it is best to first immobilize Sav on Sepharose-iminobiotin beads and then perform washing steps. Elution from the beads is achieved in an acidic reaction buffer before incubation with the cofactor. Catalysis using your test compound (in this protocol, 2-(4-(N,N-diallylsulfamoyl)phenyl)-N,N,N-trimethylethan-1-aminium iodide) is performed using the formed metalloenzyme. Screening using this approach takes 19 d. PMID:27031496

  2. The Potential of Plasma Screen Technology in Small Group Teaching for Dental Undergraduates

    OpenAIRE

    Packer, ME.; Coward, TJ.; Wakeley, R.; Fenlon

    2002-01-01

    AIM: This study was devised to ascertain the opinion of dental undergraduate students as to whether they preferred observing a live demonstration as a group directly at the workbench or indirectly on a remote Plasma Screen. In addition, to identify whether the students observing remotely believed that they had been disadvantaged by the inability to question the demonstrator during the demonstration. METHOD: 17 students divided into two groups observed a live demonstration of a laborator...

  3. Risk Perception and Social Amplification

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.E. [Environment Agency (United Kingdom)

    2001-07-01

    This paper seeks to consider social amplification as it applies to risk perception. Perceptions of the magnitude of a risk are conditioned by issues such as the degree of uncertainty in probability and consequences, the nature of the consequences and the relative weightings placed on probability and consequences. Risk perceptions are also influenced by factors such as confidence in the operator of an industrial process, trust in the regulator and the perceived fairness of regulatory decision-making. Different people may hold different views about these issues and there may also be difficulties in communication. The paper identifies and discusses self-reinforcing mechanisms, which will be labelled 'lock-in' here. They appear to apply in many situations where social amplification is observed. Historically, the term 'lock-in' has been applied mainly in the technological context but, in this paper, four types of lock-in are identified, namely scientific/technological, economic, social and institutional lock-in. One type of lock-in tends to lead to the next and all are buttressed by people's general acceptance of the familiar, fear of the unknown and resistance to change. The regulator seeks to make decisions which achieve the common good rather than supporting or perpetuating any set of vested interests. In this regard the locked-in positions of stakeholders, whether organisations, interest groups, or individual members of the public, are obstacles and challenges. Existing methods of consultation are unsatisfactory in terms of achieving a proper and productive level of dialogue with stakeholders.

  4. Productive test of a newly drying technology of veneer: intermittent-contact drying of veneer with flexible screen belt

    Institute of Scientific and Technical Information of China (English)

    HUAJun

    2005-01-01

    A newly drying technology, intermittent-contact drying of veneer with flexible screen belt (ICD-fbs), was invented and used in poplar veneer drying. Productive test was carried out for validating the practical use of this drying method. The test result shows that to dispose flexible screen belts on the two sides of hot board could help steam discharge remarkably. The veneer dried using ICD-fsb method had smooth and level surface, less deformation and warping, even moisture content, and high utilization rate. The time for opening hot board to discharge steam,which, early or late, is a key to obtain good drying result, was determined at the time when the core's temperature of veneer reaches 100℃ (vaporization). Using ICD-fsb method, the shrinking rates in tangent of veneer were from 1.90% to 2.26% for veneer of 0.4 mm in thickness,2.49% to 4.50% for veneer of 1 mm in thickness and 1.34% to 3.30% for veneer of 1.7 mm in thickness, which are much lower than the results obtained by other drying methods. The method of ICD-fsb offers a reliable technological guarantee for solving the deformation problem of veneer drying, especially the deformation of wood from quick-growing plantation.

  5. National Security Science and Technology Initiative: Air Cargo Screening, Final Report for CRADA Number NFE-07-01081

    Energy Technology Data Exchange (ETDEWEB)

    Bingham, Philip [ORNL; Bush, John [Battelle Memorial Institute; Bowerman, Biays [Brookhaven National Laboratory; Cespedes, Ernesto [Idaho National Laboratory; White, Timothy [Pacific Northwest National Laboratory

    2004-12-01

    The non-intrusive inspection (NII) of consolidated air cargo carried on commercial passenger aircraft continues to be a technically challenging, high-priority requirement of the Department of Homeland Security’s Science and Technology Directorate (DHS S&T), the Transportation Security Agency and the Federal Aviation Administration. The goal of deploying a screening system that can reliably and cost-effectively detect explosive threats in consolidated cargo without adversely affecting the flow of commerce will require significant technical advances that will take years to develop. To address this critical National Security need, the Battelle Memorial Institute (Battelle), under a Cooperative Research and Development Agreement (CRADA) with four of its associated US Department of Energy (DOE) National Laboratories (Oak Ridge, Pacific Northwest, Idaho, and Brookhaven), conducted a research and development initiative focused on identifying, evaluating, and integrating technologies for screening consolidated air cargo for the presence of explosive threats. Battelle invested $8.5M of internal research and development funds during fiscal years 2007 through 2009.

  6. 应用SMARTercDNA合成技术扩增落地生根叶片的总RNA%Total RNA Amplification from Leaves of Kalanchoe daigremontiana Using SMARTer cDNA Synthesis Technology

    Institute of Scientific and Technical Information of China (English)

    钟天秀; 曾会明

    2011-01-01

    以落地生根(Kalanchoe daigremontiana)未长芽和长芽的叶片为材料,提取落地生根的总RNA,采用SMARTer cDNA合成技术合成cDNA第1链,优化扩增第2链,通过设置梯度PCR扩增循环数,电泳分析后鉴定cDNA质量.结果表明:未长芽和长芽的材料各1μg总RNA分别成功扩增质量较高的双链cDNA.此方法的应用解决了研究材料有限的问题,可由微量的总RNA扩增出足够多的高质量双链cDNA,为进一步从基因水平研究落地生根奠定基础.%Total RNA was extracted from Kalanchoe daigremontiana leaves with or without bulbiferous spurs. The first-strand of cDNA synthesis and the double-strands cDNA amplification were performed u-sing super SMARTer cDNA synthesis technology. The quality of cDNA was evaluated through the gradient of PCR amplification cycles and electrophoresis. High quality double-strands cDNA were obtained from 1 ug total RNA. This method can solve the problem of limited research materials as sufficient high-quality double-strands cDNA are obtained from small amounts of total RNA. This technique allows further research of Kalanchoe daigremontiana.

  7. Assessing Technologies for Information-Seeking on Prostate Cancer Screening by Low-Income Men

    Directory of Open Access Journals (Sweden)

    Susan W. McRoy

    2014-11-01

    Full Text Available Purpose: This paper presents a multipart investigation of the benefits and challenges in deploying automated question-answering as an alternative to web-based searching to provide information about prostate cancer screening for low-income men age 40 years and older. Methods: The study comprised: 1 a survey assessing current use of the Internet, mobile phones and texting; 2 a controlled observational study of both web-based searching and automated question-answering for information about prostate cancer; and 3 a formative field study in which subjects interacted with a health department nurse using text messages. Results: Survey results suggest the target population has greater access to, and familiarity with, cell phones and text messaging compared to the Internet and web-based searching. Participants were significantly more confident using a cell phone and preferred to get health information through text messaging. Participants in the controlled observational study accepted the text messaging system, with most indicating it answered their questions, was easy to use and was a favorable tool for information-seeking. The field study also demonstrated potential for automated question-answering and text messaging to help the target population access health information. Conclusions: A two-way text messaging system has great potential to promote health communication and health information distribution. Participant interest in this system was high and did not seem to be specific to prostate cancer screening, suggesting that information about other topics, such as high blood pressure screening, could be provided similarly. We believe more investigations should be focused on this area, especially on benefits for the low-income community.

  8. Recommendations for cervical cancer screening programs in developing countries: the need for equity and technological development

    Directory of Open Access Journals (Sweden)

    Lazcano-Ponce Eduardo

    2003-01-01

    Full Text Available The cervical cancer screening programs (CCSP have not been very efficient in the developing countries. This explains the need to foster changes on policies, standards, quality control mechanisms, evaluation and integration of new screening alternatives considered as low and high cost, as well as to regulate colposcopy practices and the foundation of HPV laboratories. Cervical cancer (CC is a disease most frequently found in poverty-stricken communities and reflecting a problem of equity at both levels gender and regional, and this, is not only due to social and economic development inequalities, but to the infrastructure and human resources necessary for primary care. For this reason, the CCSP program must be restructured, a to primarily address unprivileged rural and urban areas; b to foster actions aimed at ensuring extensive coverage as well as a similar quality of that coverage in every region; c to use screening strategies in keeping with the availability of health care services. In countries with a great regional heterogeneity, a variety of screening procedures must be regulated and standardized, including a combination of assisted visual inspection, cervical cytology and HPV detection; d regional community intervention must be set up to assess the effectiveness of using HPV detection as an strategy in addition to cervical cytology (pap smear; e the practice of colposcopy must be regulated to prevent the use of it in healthy women at a population level, thus preventing unnecessary diagnosis and treatment which not only are expensive but also causes unnecessary anxiety to women at risk; f the operation of those clinical laboratories using HPV as a detection strategy must likewise be accredited and regulated and g the CCSP program for assuring health care quality should meet the expectations of its beneficiaries, and increase the knowledge in cervical cancer related matters. Finally, though a variety of clinical tests on prophylactic and

  9. [Health technology assessment report. Use of liquid-based cytology for cervical cancer precursors screening].

    Science.gov (United States)

    Ronco, Guglielmo; Confortini, Massimo; Maccallini, Vincenzo; Naldoni, Carlo; Segnan, Nereo; Sideri, Mario; Zappa, Marco; Zorzi, Manuel; Calvia, Maria; Giorgi Rossi, Paolo

    2012-01-01

    OBJECTIVE OF THE PROJECT: Purpose of this Report is to evaluate the impact of the introduction of liquid-based cytology (LBC) in cervical cancer screening in terms of efficacy, undesired effects, costs and implications for organisation. EFFICACY AND UNDESIRED EFFECTS: LBC WITH MANUAL INTERPRETATION: The estimates of cross-sectional accuracy for high-grade intraepithelial neoplasia (CIN2 or more severe and CIN3 or more severe) obtained by a systematic review and meta-analysis published in 2008 were used. This review considered only studies in which all women underwent colposcopy or randomised controlled trials (RCTs) with complete verification of test positives. A systematic search of RCTs published thereafter was performed. Three RCTs were identified. One of these studies was conducted in 6 Italian regions and was of large size (45,174 women randomised); a second one was conducted in another Italian region (Abruzzo) and was of smaller size (8,654 women randomised); a third RCT was conducted in the Netherlands and was of large size (89,784 women randomised). No longitudinal study was available. There is currently no clear evidence that LBC increases the sensitivity of cytology and even less that its introduction increases the efficacy of cervical screening in preventing invasive cancers. The Italian randomised study NTCC showed a decrease in specificity, which was not observed in the other two RCTs available. In addition, the 2008 meta-analysis observed a reduction - even if minimal - in specificity just at the ASC-US cytological cut-off, but also a remarkable heterogeneity between studies. These results suggest that the effect of LBC on specificity is variable and plausibly related to the local style of cytology interpretation. There is evidence that LBC reduces the proportion of unsatisfactory slides, although the size of this effect varies remarkably. LBC WITH COMPUTER-ASSISTED INTERPRETATION: An Australian study, based on double testing, showed a statistically

  10. Towards a full karyotype screening of interphase cells: 'FISH and chip' technology

    Energy Technology Data Exchange (ETDEWEB)

    Weier, Heinz-Ulli G.; Munne, Santiago; Lersch, Robert A.; Hsieh, H.-Ben; Smida, Jan; Chen, Xiao-Ning; Korenberg, Julie R.; Pedersen, Roger A.; Fung, Jingley

    2003-06-23

    Numerical chromosome aberrations are incompatible with normal human development. Our laboratories develop hybridization based screening tools that generate a maximum of cytogenetic information for each polar body or blastomere analyzed. The methods are developed considering that the abnormality might require preparation of case-specific probes and that only one or two cells will be available for diagnosis, most of which might be in the interphase stage. Further more, assay efficiencies have to be high, since there is typically not enough time to repeat an experiment or reconfirm a result prior to fertilization or embryo transfer. Structural alterations are delineated with break point-spanning probes. When screening for numerical abnormalities, we apply a Spectral Imaging-based approach to simultaneously score as many as ten different chromosome types in individual inter phase cells. Finally, DNA micro-arrays are under development to score all of the human chromosomes in a single experiment and to increase the resolution with which micro-deletions can be delineated.

  11. Splitting of 3d quaternion dimensions into 2d-sells and a "world screen technology"

    CERN Document Server

    Yefremov, Alexander P

    2012-01-01

    A set of basic vectors locally describing metric properties of an arbitrary 2-dimensional (2D) surface is used for construction of fundamental algebraic objects having nilpotent and idempotent properties. It is shown that all possible linear combinations of the objects when multiplied behave as a set of hypercomples (in particular, quaternion) units; thus interior structure of the 3D space dimensions pointed by the vector units is exposed. Geometric representations of elementary surfaces (2D-sells) structuring the dimensions are studied in detail. Established mathematical link between a vector quaternion triad treated as a frame in 3D space and elementary 2D-sells prompts to raise an idea of "world screen" having 1/2 of a space dimension but adequately reflecting kinematical properties of an ensemble of 3D frames.

  12. High throughput screening strategies and technology platforms for detection of pathogens: An Introduction

    Science.gov (United States)

    Globally, foodborne pathogens are a major public health concern. In this chapter, we provide a broad description of the problem of food-borne diseases and current and future detection technologies for food safety assurance and prevention of foodborne illnesses. Current detection approaches include s...

  13. Impedance sensor technology for cell-based assays in the framework of a high-content screening system

    International Nuclear Information System (INIS)

    Living cultured cells react to external influences, such as pharmaceutical agents, in an intricate manner due to their complex internal signal processing. Impedance sensing of cells on microelectrodes is a favored label-free technology to indicate cellular events, usually ascribed to morphologic alteration or changes in cellular adhesion, which is usually found in stand-alone systems that do not incorporate life support or additional sensor systems. However, only in symbiosis with metabolic activity sensing and picture documentation may a complete insight into cellular vitality be provided. This complement was created within the framework of an automated high-content screening system previously developed by our group, monitoring 24 cell culture chambers in parallel. The objective of this paper is the development of miniaturized electronics for impedance measurements and its system integration as a modular unit. In addition, it is shown how sensor electrodes were optimized by impedance matching such that spectroscopy and raw data analysis become feasible for every culture well. Undesired mechanical stress on cultured cells may arise from the medium and agent support system of the autonomous screening apparatus. This paper demonstrates how this hazard is treated with the simulation of microfluidics and impedance measurements. Physiological data are subsequently derived from the exemplary tumor cell line MCF-7 both during treatment with the agent doxorubicin and through the impact of natural killer cells. This correlates the information content of complex impedance spectra with cellular respiration as well as data from microscopy

  14. The disposal of Canada's nuclear fuel waste: site screening and site evaluation technology

    International Nuclear Information System (INIS)

    The concept for the disposal of Canada's nuclear fuel waste is to dispose of the waste in an underground vault, nominally at 500 m to 1000 m depth, at a suitable site in plutonic rock of the Canadian Shield. The feasibility of this concept and assessments of its impact on the environment and human health, will be documented by AECL in an Environmental Impact Statement (EIS). This report is one of nine primary references for the EIS. It describes the approach and methods that would be used during the siting stage of the disposal project to identify a preferred candidate disposal site and to confirm its suitability for constructing a disposal facility. The siting stage is divided into two distinct but closely related substages, site screening and site evaluation. Site screening would mainly involve reconnaissance investigations of siting regions of the Shield to identify potential candidate areas where suitable vault locations are likely to exist. Site screening would identify a small number of candidate areas where further detailed investigations were warranted. Site evaluation would involve progressively more detailed surface and subsurface investigations of the candidate areas to first identify potentially suitable vault locations within the candidate areas, and then characterize these potential disposal sites to identify the preferred candidate location for constructing the disposal vault. Site evaluation would conclude with the construction of exploratory shafts and tunnels at the preferred vault location, and underground characterization would be done to confirm the suitability of the preferred candidate site. An integrated program of geological, geophysical, hydrogeological, geochemical and geomechanical investigations would be implemented to obtain the geoscience information needed to assess the suitability of the candidate siting areas and candidate sites for locating a disposal vault. The candidate siting areas and candidate disposal vault sites would be

  15. Evidence of high-elevation amplification versus Arctic amplification

    Science.gov (United States)

    Wang, Qixiang; Fan, Xiaohui; Wang, Mengben

    2016-01-01

    Elevation-dependent warming in high-elevation regions and Arctic amplification are of tremendous interest to many scientists who are engaged in studies in climate change. Here, using annual mean temperatures from 2781 global stations for the 1961-2010 period, we find that the warming for the world’s high-elevation stations (>500 m above sea level) is clearly stronger than their low-elevation counterparts; and the high-elevation amplification consists of not only an altitudinal amplification but also a latitudinal amplification. The warming for the high-elevation stations is linearly proportional to the temperature lapse rates along altitudinal and latitudinal gradients, as a result of the functional shape of Stefan-Boltzmann law in both vertical and latitudinal directions. In contrast, neither altitudinal amplification nor latitudinal amplification is found within the Arctic region despite its greater warming than lower latitudes. Further analysis shows that the Arctic amplification is an integrated part of the latitudinal amplification trend for the low-elevation stations (≤500 m above sea level) across the entire low- to high-latitude Northern Hemisphere, also a result of the mathematical shape of Stefan-Boltzmann law but only in latitudinal direction.

  16. Efficiency evaluation for remediating paddy soil contaminated with cadmium and arsenic using water management, variety screening and foliage dressing technologies.

    Science.gov (United States)

    Liao, Guojian; Wu, Qianhua; Feng, Renwei; Guo, Junkang; Wang, Ruigang; Xu, Yingming; Ding, Yongzhen; Fan, Zhilian; Mo, Liangyu

    2016-04-01

    Paddy soils in many regions of China have been seriously polluted by multiple heavy metals or metalloids, such as arsenic (As), cadmium (Cd) and lead (Pb). In order to ensure the safety of food and take full advantage of the limited farmland resources of China, exploring an effective technology to repair contaminated soils is urgent and necessary. In this study, three technologies were employed, including variety screening, water management and foliage dressing, to assess their abilities to reduce the accumulation of Cd and As in the grains of different rice varieties, and meanwhile monitor the related yields. The results of variety screening under insufficient field drying condition showed that the As and Cd contents in the grains of only four varieties [Fengliangyouxiang 1 (P6), Zhongzheyou 8 (P7), Guangliangyou 1128 (P10), Y-liangyou 696 (P11)] did not exceed their individual national standard. P6 gained a relatively high grain yield but accumulated less As and Cd in the grains despite of the relatively high As and Cd concentrations in the rhizosphere soil. However, long-playing field drying in water management trial significantly increased Cd but decreased As content in the grains of all tested three varieties including P6, suggesting an important role of water supply in controlling the accumulation of grain As and Cd. Selenium (Se) showed a stronger ability than silicon (Si) to reduce As and Cd accumulation in the grains of Fengliangyou 4 (P2) and Teyou 524 (P13), and keep the yields. The results of this study suggest that combined application of water management and foliage dressing may be an efficient way to control As and Cd accumulation in the grains of paddy rice exposing to As- and Cd-contaminated soils. PMID:26807822

  17. Information Technology and Screen-Based Securities Trading: Pricing the Stock and Pricing the Trade

    OpenAIRE

    Eric K. Clemons; Bruce W. Weber

    1997-01-01

    Many major stock exchanges rely on their member firms to act as dealer intermediaries, risking their own capital to trade as dealers with investor customers. A confluence of forces will dramatically alter the role of these intermediaries and the strategies available to them. Information technology is increasing the diversity of trading strategies used by investors; these impose different costs and risks upon intermediaries. Alternative electronic trading venues---off-exchange trading systems-...

  18. Designing for Small Screens: Learning Objects for Educational Applications via Handheld Mobile Technologies

    OpenAIRE

    Churchill, D

    2006-01-01

    This presentation discusses an ongoing study into issues relevant to the design of learning objects for educational applications via PDA devices. The specific areas of inquiry in this study are: the kinds of learning objects that are effective for PDA delivery; contexts for their effective educational applications; and learning object designs that overcome the limitations of the small display area characteristic of this kind of technology. Data from the study suggests that a learning object e...

  19. Intangible Transfers of Technology and Visa Screening in the European Union

    OpenAIRE

    Garrido Rebolledo, Vicente

    2012-01-01

    In December 2008 the European Union (EU) adopted political guidelines introducing measures to combat intangible transfers of technology (ITT), including mechanisms for cooperation in terms of consular vigilance. United Nations Security Council resolutions concerning Iran and North Korea further prohibit EU member states from ITT to these countries of concern. This paper deals with two key aspects of ITT: foreign nationals interested in sensitive disciplines and uncontrolled outflows of sensit...

  20. Efficient audio power amplification - challenges

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Michael A.E.

    2005-07-01

    For more than a decade efficient audio power amplification has evolved and today switch-mode audio power amplification in various forms are the state-of-the-art. The technical steps that lead to this evolution are described and in addition many of the challenges still to be faced and where extensive research and development are needed is covered. (au)

  1. Gene amplification during myogenic differentiation

    Science.gov (United States)

    Fischer, Ulrike; Ludwig, Nicole; Raslan, Abdulrahman; Meier, Carola; Meese, Eckart

    2016-01-01

    Gene amplifications are mostly an attribute of tumor cells and drug resistant cells. Recently, we provided evidence for gene amplifications during differentiation of human and mouse neural progenitor cells. Here, we report gene amplifications in differentiating mouse myoblasts (C2C12 cells) covering a period of 7 days including pre-fusion, fusion and post-fusion stages. After differentiation induction we found an increase in copy numbers of CDK4 gene at day 3, of NUP133 at days 4 and 7, and of MYO18B at day 4. The amplification process was accompanied by gamma-H2AX foci that are indicative of double stand breaks. Amplifications during the differentiating process were also found in primary human myoblasts with the gene CDK4 and NUP133 amplified both in human and mouse myoblasts. Amplifications of NUP133 and CDK4 were also identified in vivo on mouse transversal cryosections at stage E11.5. In the course of myoblast differentiation, we found amplifications in cytoplasm indicative of removal of amplified sequences from the nucleus. The data provide further evidence that amplification is a fundamental mechanism contributing to the differentiation process in mammalians. PMID:26760505

  2. Efficient Audio Power Amplification - Challenges

    DEFF Research Database (Denmark)

    Andersen, Michael Andreas E.

    2005-01-01

    For more than a decade efficient audio power amplification has evolved and today switch-mode audio power amplification in various forms are the state-of-the-art. The technical steps that lead to this evolution are described and in addition many of the challenges still to be faced and where...

  3. Monolithic pixel detectors in a 0.13μm CMOS technology with sensor level continuous time charge amplification and shaping

    International Nuclear Information System (INIS)

    This work studies the feasibility of a new implementation of CMOS monolithic active pixel sensors (MAPS) for applications to charged particle tracking. As compared to standard three MOSFET MAPS, where the charge signal is readout by a source follower, the proposed front-end scheme relies upon a charge sensitive amplifier (CSA), embedded in the elementary pixel cell, to perform charge-to-voltage conversion. The area required for the integration of the front-end electronics is mostly provided by the collecting electrode, which consists of a deep n-type diffusion, available as a shielding frame for n-channel devices in deep submicron, triple well CMOS technologies. Based on the above concept, a chip, which includes several test structures differing in the sensitive element area, has been fabricated in a 0.13μm CMOS process. In this paper, the criteria underlying the design of the pixel level analog processor will be presented, together with some preliminary experimental results demonstrating the feasibility of the proposed approach

  4. Evidence of high-elevation amplification versus Arctic amplification

    OpenAIRE

    Qixiang Wang; Xiaohui Fan; Mengben Wang

    2016-01-01

    Elevation-dependent warming in high-elevation regions and Arctic amplification are of tremendous interest to many scientists who are engaged in studies in climate change. Here, using annual mean temperatures from 2781 global stations for the 1961–2010 period, we find that the warming for the world’s high-elevation stations (>500 m above sea level) is clearly stronger than their low-elevation counterparts; and the high-elevation amplification consists of not only an altitudinal amplification b...

  5. Differential screening of phage-ab libraries by oligonucleotide microarray technology.

    Directory of Open Access Journals (Sweden)

    Paolo Monaci

    Full Text Available A novel and efficient tagArray technology was developed that allows rapid identification of antibodies which bind to receptors with a specific expression profile, in the absence of biological information. This method is based on the cloning of a specific, short nucleotide sequence (tag in the phagemid coding for each phage-displayed antibody fragment (phage-Ab present in a library. In order to set up and validate the method we identified about 10,000 different phage-Abs binding to receptors expressed in their native form on the cell surface (10 k Membranome collection and tagged each individual phage-Ab. The frequency of each phage-Ab in a given population can at this point be inferred by measuring the frequency of its associated tag sequence through standard DNA hybridization methods. Using tiny amounts of biological samples we identified phage-Abs binding to receptors preferentially expressed on primary tumor cells rather than on cells obtained from matched normal tissues. These antibodies inhibited cell proliferation in vitro and tumor development in vivo, thus representing therapeutic lead candidates.

  6. Neuroblastoma Screening

    Science.gov (United States)

    ... Health Professional Neuroblastoma Treatment Neuroblastoma Screening Research Neuroblastoma Screening (PDQ®)–Patient Version What is screening? Go to Health Professional Version Screening is looking ...

  7. Next generation Chirped Pulse Amplification

    Energy Technology Data Exchange (ETDEWEB)

    Nees, J.; Biswal, S.; Mourou, G. [Univ. Michigan, Center for Ultrafast Optical Science, Ann Arbor, MI (United States); Nishimura, Akihiko; Takuma, Hiroshi

    1998-03-01

    The limiting factors of Chirped Pulse Amplification (CPA) are discussed and experimental results of CPA in Yb:glass regenerative amplifier are given. Scaling of Yb:glass to the petawatt level is briefly discussed. (author)

  8. Application of PCR-DHPLC technology in Down's syndrome screening%聚合酶链式反应-变性高效液相色谱技术在唐氏综合征筛查中的应用

    Institute of Scientific and Technical Information of China (English)

    张丹妍; 马明福; 张丹媚; 朱一剑; 吕静; 赵乐天; 万凌; 侯志伟; 李练兵

    2012-01-01

    目的:探讨聚合酶链式反应-变性高效液相色谱技术(polymerase chain reaction-denaturing high performance liquid chromatography,PCR-DHPLC)在唐氏综合征筛查中的应用.方法:针对21号染色体上的基因座D21S1409、D21S1422、D21S1435和GATA163G03设计引物,PCR扩增唐氏综合征患儿样本和正常样本,DHPLC仪检测;同步进行外周血染色体核型分析,并以核型分析为金标准,评价PCR-DHPLC技术的准确性.结果:柱温50℃时,唐氏综合征患儿样本DHPLC检测结果呈现特异唐氏综合征峰.结论:PCR-DHPLC方法具有较高的敏感性和特异性,可用于唐氏综合征的高通量快速筛查.%OBJECTIVE: To evaluate the use of polymerase chain reaction-denaturing high performance liquid chromatography technology (PCR-DHPLC) in Down syndrome screening. METHODS: Primers of D21S1409, D21S1422, D21S1435 and GATA163G03 loci on chromosome 21 were designed. The samples of the children with Down's syndrome or the normal ones were amplified using PCR method. The PCR amplification products were identified by denaturing high performance liquid chromatography technology. At the same time the same samples were analyzed with karyotyping, to evaluate the accuracy of PCR-DHPLC. RESULTS: The column temperature was 50 ℃ , the Down syndrome samples showed specific DHPLC peak of Down syndrome. CONCLUSION: The PCR-DHPLC method edmonstrated high sensitivity and specificity. It could be used in high-throughput rapid screening for Down's syndrome.

  9. Recombinase Polymerase Amplification (RPA of CaMV-35S Promoter and nos Terminator for Rapid Detection of Genetically Modified Crops

    Directory of Open Access Journals (Sweden)

    Chao Xu

    2014-10-01

    Full Text Available Recombinase polymerase amplification (RPA is a novel isothermal DNA amplification and detection technology that enables the amplification of DNA within 30 min at a constant temperature of 37–42 °C by simulating in vivo DNA recombination. In this study, based on the regulatory sequence of the cauliflower mosaic virus 35S (CaMV-35S promoter and the Agrobacterium tumefaciens nopaline synthase gene (nos terminator, which are widely incorporated in genetically modified (GM crops, we designed two sets of RPA primers and established a real-time RPA detection method for GM crop screening and detection. This method could reliably detect as few as 100 copies of the target molecule in a sample within 15–25 min. Furthermore, the real-time RPA detection method was successfully used to amplify and detect DNA from samples of four major GM crops (maize, rice, cotton, and soybean. With this novel amplification method, the test time was significantly shortened and the reaction process was simplified; thus, this method represents an effective approach to the rapid detection of GM crops.

  10. Recombinase polymerase amplification (RPA) of CaMV-35S promoter and nos terminator for rapid detection of genetically modified crops.

    Science.gov (United States)

    Xu, Chao; Li, Liang; Jin, Wujun; Wan, Yusong

    2014-01-01

    Recombinase polymerase amplification (RPA) is a novel isothermal DNA amplification and detection technology that enables the amplification of DNA within 30 min at a constant temperature of 37-42 °C by simulating in vivo DNA recombination. In this study, based on the regulatory sequence of the cauliflower mosaic virus 35S (CaMV-35S) promoter and the Agrobacterium tumefaciens nopaline synthase gene (nos) terminator, which are widely incorporated in genetically modified (GM) crops, we designed two sets of RPA primers and established a real-time RPA detection method for GM crop screening and detection. This method could reliably detect as few as 100 copies of the target molecule in a sample within 15-25 min. Furthermore, the real-time RPA detection method was successfully used to amplify and detect DNA from samples of four major GM crops (maize, rice, cotton, and soybean). With this novel amplification method, the test time was significantly shortened and the reaction process was simplified; thus, this method represents an effective approach to the rapid detection of GM crops. PMID:25310647

  11. LD pumped Nd: YLF amplification technology

    International Nuclear Information System (INIS)

    A Ring-LD-pumped Nd: YLF laser amplifier system is theoretically and experimentally discussed. A structure of off-axes double passes amplifier is used. The results of experiment shown that 109 mJ output energy with a net gain of 1115 is obtained under 150 μJ input energy; a compact side-pumped structure is used to obtain a high transferring efficiency of LD array, 1.01 J output energy is achieved at 1053 nm. (authors)

  12. Genome-wide array comparative genomic hybridization analysis reveals distinct amplifications in osteosarcoma

    International Nuclear Information System (INIS)

    Osteosarcoma is a highly malignant bone neoplasm of children and young adults. It is characterized by extremely complex karyotypes and high frequency of chromosomal amplifications. Currently, only the histological response (degree of necrosis) to therapy represent gold standard for predicting the outcome in a patient with non-metastatic osteosarcoma at the time of definitive surgery. Patients with lower degree of necrosis have a higher risk of relapse and poor outcome even after chemotherapy and complete resection of the primary tumor. Therefore, a better understanding of the underlying molecular genetic events leading to tumor initiation and progression could result in the identification of potential diagnostic and therapeutic targets. We used a genome-wide screening method – array based comparative genomic hybridization (array-CGH) to identify DNA copy number changes in 48 patients with osteosarcoma. We applied fluorescence in situ hybridization (FISH) to validate some of amplified clones in this study. Clones showing gains (79%) were more frequent than losses (66%). High-level amplifications and homozygous deletions constitute 28.6% and 3.8% of tumor genome respectively. High-level amplifications were present in 238 clones, of which about 37% of them showed recurrent amplification. Most frequently amplified clones were mapped to 1p36.32 (PRDM16), 6p21.1 (CDC5L, HSPCB, NFKBIE), 8q24, 12q14.3 (IFNG), 16p13 (MGRN1), and 17p11.2 (PMP22 MYCD, SOX1,ELAC27). We validated some of the amplified clones by FISH from 6p12-p21, 8q23-q24, and 17p11.2 amplicons. Homozygous deletions were noted for 32 clones and only 7 clones showed in more than one case. These 7 clones were mapped to 1q25.1 (4 cases), 3p14.1 (4 cases), 13q12.2 (2 cases), 4p15.1 (2 cases), 6q12 (2 cases), 6q12 (2 cases) and 6q16.3 (2 cases). This study clearly demonstrates the utility of array CGH in defining high-resolution DNA copy number changes and refining amplifications. The resolution of array CGH

  13. Optical Parametric Amplification for High Peak and Average Power

    Energy Technology Data Exchange (ETDEWEB)

    Jovanovic, I

    2001-11-26

    Optical parametric amplification is an established broadband amplification technology based on a second-order nonlinear process of difference-frequency generation (DFG). When used in chirped pulse amplification (CPA), the technology has been termed optical parametric chirped pulse amplification (OPCPA). OPCPA holds a potential for producing unprecedented levels of peak and average power in optical pulses through its scalable ultrashort pulse amplification capability and the absence of quantum defect, respectively. The theory of three-wave parametric interactions is presented, followed by a description of the numerical model developed for nanosecond pulses. Spectral, temperature and angular characteristics of OPCPA are calculated, with an estimate of pulse contrast. An OPCPA system centered at 1054 nm, based on a commercial tabletop Q-switched pump laser, was developed as the front end for a large Nd-glass petawatt-class short-pulse laser. The system does not utilize electro-optic modulators or multi-pass amplification. The obtained overall 6% efficiency is the highest to date in OPCPA that uses a tabletop commercial pump laser. The first compression of pulses amplified in highly nondegenerate OPCPA is reported, with the obtained pulse width of 60 fs. This represents the shortest pulse to date produced in OPCPA. Optical parametric amplification in {beta}-barium borate was combined with laser amplification in Ti:sapphire to produce the first hybrid CPA system, with an overall conversion efficiency of 15%. Hybrid CPA combines the benefits of high gain in OPCPA with high conversion efficiency in Ti:sapphire to allow significant simplification of future tabletop multi-terawatt sources. Preliminary modeling of average power limits in OPCPA and pump laser design are presented, and an approach based on cascaded DFG is proposed to increase the average power beyond the single-crystal limit. Angular and beam quality effects in optical parametric amplification are modeled

  14. Social amplification of risk: An empirical study

    International Nuclear Information System (INIS)

    The social amplification of risk is a theoretical framework that addresses an important deficiency of formal risk assessment methods and procedures. Typically assessments of risk from technological mishaps have been based upon the expected number of people who could be killed or injured or the amount of property that might be damaged. The diverse and consequential impacts that followed in the aftermath of the Three Mile Island accident make it clear that risk assessments that exclude the role of public perceptions of risk will greatly underestimate the potential costs of certain types of hazards. The accident at Three Mile Island produced no direct fatalities and few, if any, expected deaths due to cancer, yet few other accidents in history have had such costly societal impacts. The experience of amplified impacts argues for the development of a broadened theoretical and methodological perspective capable of integrating technical assessment of risk with public perceptions. This report presents the results to date in an ongoing research effort to better understand the complex processes by which adverse events produce impacts. In particular this research attempts to construct a framework that can account for those events that have produced, or are capable of producing, greater societal impacts than would be forecast by traditional risk assessment methods. This study demonstrates that the social amplification of risk involves interactions between sophisticated technological hazards, public and private institutions, and subtle individual and public perceptions and behaviors. These factors, and the variables underlying the intricate processes of social amplification that occur in modern society, are not fully defined and clarified in this report. 19 refs., 9 figs., 10 tabs

  15. Second-generation non-invasive high-throughput DNA sequencing technology in the screening of Down's syndrome in advanced maternal age women

    Science.gov (United States)

    ZHANG, JIAO; ZHANG, BIN

    2016-01-01

    The aim of the present study was to evaluate the efficacy of using non-invasive DNA testing technology in screening Down's syndrome among women of advanced maternal age (AMA) and to provide evidence for prenatal screening of Down's syndrome. With a double-blind design, 8 ml of peripheral venous blood samples were collected from 87 women aged ≥35 years after 12 weeks of pregnancy. All cases were recorded with unique identification cards with clinical details and followed up until delivery. All the non-invasive prenatal testing results were confirmed by amniotic fluid fetal karyotyping (the gold standard of aneuploidy test), follow-up examination by neonatologists or neonatal blood karyotyping. The sensitivity, specificity and other indicators of non-invasive DNA testing technology were calculated based on the data of 87 women of AMA. Among the 87 women of AMA, 5 were cases with abnormal numbers of chromosomes (3 cases of trisomy 21, 1 case of trisomy 18 and 1 case of 47, XXX). The sensitivity and specificity reached 100% for trisomy 21, trisomy 18 and 47, XXX. The present study supports that non-invasive DNA testing is a useful method of AMA screening of Down's syndrome with 100% accuracy. Therefore, it can be used as an important alternative screening method for Down's syndrome in women of AMA. PMID:27313855

  16. Rapid amplification of genetically modified organisms using a circular ferrofluid-driven PCR microchip.

    Science.gov (United States)

    Sun, Yi; Kwok, Yien-Chian; Foo-Peng Lee, Peter; Nguyen, Nam-Trung

    2009-07-01

    The use of genetically modified organisms (GMOs) as food and in food products is becoming more and more widespread. Polymerase chain reaction (PCR) technology is extensively used for the detection of GMOs in food products in order to verify compliance with labeling requirements. In this paper, we present a novel close-loop ferrofluid-driven PCR microchip for rapid amplification of GMOs. The microchip was fabricated in polymethyl methacrylate by CO2 laser ablation and was integrated with three temperature zones. PCR solution was contained in a circular closed microchannel and was driven by magnetic force generated by an external magnet through a small oil-based ferrofluid plug. Successful amplification of genetically modified soya and maize were achieved in less than 13 min. This PCR microchip combines advantages of cycling flexibility and quick temperature transitions associated with two existing microchip PCR techniques, and it provides a cost saving and less time-consuming way to conduct preliminary screening of GMOs. PMID:19399482

  17. The Investigation of Sudden Arrhythmic Death Syndrome (SADS – the current approach to family screening and the future role of genomics & stem cell technology

    Directory of Open Access Journals (Sweden)

    Vishal eVyas

    2013-09-01

    Full Text Available SADS is defined as sudden death under the age of 40 years old in the absence of structural heart disease. Family screening studies are able to identify a cause in up to 50% of cases-most commonly long QT syndrome, Brugada and early repolarisation syndrome, and catecholaminergic polymorphic ventricular tachycardia using standard clinical screening investigations including pharmacological challenge testing. These diagnoses may be supported by genetic testing which can aid cascade screening and may help guide management. In the current era it is possible to undertake molecular autopsy provided suitable samples of DNA can be obtained from the proband. With the evolution of rapid sequencing techniques it is possible to sequence the whole exome for candidate genes. This major advance offers the opportunity to identify novel causes of lethal arrhythmia but also poses the challenge of managing the volume of data generated and evaluating variants of unknown significance. The emergence of induced pluripotent stem cell technology could enable evaluation of the electrophysiological relevance of specific ion channel mutations in the proband or their relatives and will potentially enable screening of idiopathic ventricular fibrillation survivors combining genetic and electrophysiological studies in derived myocytes. This also could facilitate the assessment of personalised preventative pharmacological therapies. This review will evaluate the current screening strategies in SADS families, the role of molecular autopsy and genetic testing and the potential applications of molecular and cellular diagnostic strategies on the horizon.

  18. Impact of human genome initiative-derived technology on genetic testing, screening and counseling: Cultural, ethical and legal issues

    Energy Technology Data Exchange (ETDEWEB)

    Trottier, R.W.; Hodgin, F.C.; Imara, M.; Phoenix, D.; Lybrook, S. (Morehouse Coll., Atlanta, GA (United States). School of Medicine); Crandall, L.A.; Moseley, R.E.; Armotrading, D. (Florida Univ., Gainesville, FL (United States). Coll. of Medicine)

    1993-01-01

    Genetic medical services provided by the Georgia Division of Public Health in two northern and two central districts are compared to services provided in a district in which a tertiary care facility is located. Genetics outreach public health nurses play key roles in Georgia's system of Children's Health Services Genetics Program, including significant roles as counselors and information sources on special needs social services and support organizations. Unique features of individual health districts, (e.g., the changing face of some rural communities in ethnocultural diversity and socioeconomic character), present new challenges to current and future genetics services delivery. Preparedness as to educational needs of both health professionals and the lay population is of foremost concern in light of the ever expanding knowledge and technology in medical genetics. Perspectives on genetics and an overview of services offered by a local private sector counselor are included for comparison to state supported services. The nature of the interactions which transpire between private and public genetic services resources in Georgia will be described. A special focus of this research includes issues associated with sickle cell disease newborn screening service delivery process in Georgia, with particular attention paid to patient follow-up and transition to primary care. Of particular interest to this focus is the problem of loss to follow-up in the current system. Critical factors in education and counseling of sickle cell patients and the expectations of expanding roles of primary care physicians are discussed. The Florida approach to the delivery of genetic services contrasts to the Georgia model by placing more emphasis on a consultant-specialist team approach.

  19. Cost-effectiveness of quantitative ultrasound as a technique for screening of osteoporotic fracture risk: report on a health technology assessment conducted in 2001

    OpenAIRE

    Wasem, Jürgen; Hessel, Franz; Aidelsburger, Pamela

    2004-01-01

    Aim: On behalf of the German Agency for Health Technology Assessment (DAHTA@DIMDI) a rapid economic HTA was conducted. Aim of the HTA was to evaluate the cost-effectiveness of quantitative ultrasound (QUS) for screening of osteoporotic fracture risk. Study population was formed by postmenopausal women. QUS was compared to the dual X-ray absorptiometry (DXA) as the most frequently used method of measurement. Methods: According to the recommendations for rapid economic HTA a comprehensive liter...

  20. Feedback Amplification of Neutrophil Function.

    Science.gov (United States)

    Németh, Tamás; Mócsai, Attila

    2016-06-01

    As the first line of innate immune defense, neutrophils need to mount a rapid and robust antimicrobial response. Recent studies implicate various positive feedback amplification processes in achieving that goal. Feedback amplification ensures effective migration of neutrophils in shallow chemotactic gradients, multiple waves of neutrophil recruitment to the site of inflammation, and the augmentation of various effector functions of the cells. We review here such positive feedback loops including intracellular and autocrine processes, paracrine effects mediated by lipid (LTB4), chemokine, and cytokine mediators, and bidirectional interactions with the complement system and with other immune and non-immune cells. These amplification mechanisms are not only involved in antimicrobial immunity but also contribute to neutrophil-mediated tissue damage under pathological conditions. PMID:27157638

  1. 多重连接探针扩增(MLPA)技术同时检测五种病毒的研究%Simultaneous Detection of Five Virues by Multiplex Ligation-dependent Probe Amplification(MLPA) Technology

    Institute of Scientific and Technical Information of China (English)

    史喜菊; 马贵平; 乔彩霞; 郭志红; 张伟; 刘全国; 李炎鑫; 李冰玲

    2013-01-01

    Current detection technologies for diagnosis of animal diseases is mostly targeted at single pathogen,but the prevalence of animal diseases is characterized by mixed infection with more than one pathogen.In order to resolve the trouble,here we describe the new multiparameter assay,which is based on multiplex ligation-dependent probe amplification(MLPA) technology with the advantages of specificity,sensitivity and high-throughput.Five pairs of specific probe targeted at Swine influenza virus(SIV),Pseudorabies virus(PRV),Foot and mouth disease virus (FMDV),Transmissible gastroenteritis virus (TGEV) and Porcine reproductive and respiratory syndrome virus (PRRSV),were designed,respectiviely.The mixture of five standard RNA/DNA was used as template,together with the mixture of these probes as probe and the PCR universal primer,one MLPA method for simultaneous detection of the five porcine viruses was developed.The result of specificity test showed that the designed probes had good specificity without mismatch between each virus-specific probe pair and other six viruses,and that the mixture of the five pairs of probe only amplified the corresponding one specific fragment from the eight virus templates,respectively,no amplification signal was produced among Porcine parvovirus(PPV),Classical swine fever virus(CSFV) and Porcine epidemic diarrhea virus(PEDV) with the same probe mixture.The result of sensitivity test showed that the concentration of nucleic acid of single virus in one MLPA reaction was up to 3 000~6 000 copies.All the results showed that the developed MLPA method in this article accomplished the simultaneous detection of five viruses in one reaction,which indicates MLPA technology may be an alternative to simultaneous detection of many pathogens in the future in the field of veterinary medicine.%现有的动物疫病诊断技术多是针对单一病原进行的,而动物疫病的流行却出现了多种病毒混合感染,现有诊断技术不能很好地

  2. 膨胀筛管螺纹连接技术研究%A Preliminary Study of the Thread Connection Technology for Expandable Screen Pipe

    Institute of Scientific and Technical Information of China (English)

    宁学涛; 吴柳根; 唐成磊; 唐明

    2012-01-01

    The thread connection technology is one of the key technologies for expandable screen pipe. The technological breakthrough is of vital significance to research on the technology of expandable screen. The ANSYS software was adopted to conduct a finite element calculation of the slotted barb-tooth thread to obtain the finite element analysis result, find out the design defects of the simulated thread structure, propose the corresponding sohtion and conduct several tests with the expandable screen thread after improvement, such as expansion test, tensile test, downhole simulation test and intra-pipe sand control test. The experimental findings show that the expandable screen thread adopting coordinate groove and pin tightening can better satisfy the requirements of screen connection and expansion. It can serve as the connection thread of expandable screen pipe.%螺纹连接技术是膨胀管的核心技术之一,突破该技术对膨胀筛管技术的研究具有至关重要的意义。利用ANSYS软件对带有割缝的倒钩齿螺纹进行有限元计算,得到螺纹膨胀变形后的有限元分析结果,找出模拟螺纹结构的设计缺陷,提出了相应的解决方法,并对改进后的膨胀筛管螺纹进行了膨胀试验、抗拉试验、井下模拟试验及管内防砂试验。试验结果表明,膨胀筛管螺纹采用配合槽和销钉紧固设计,能够较好地满足筛管连接及膨胀要求,可以作为膨胀筛管的连接螺纹。

  3. Amplification of Short Pulse High Power UV Laser

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    At recent year, with the development of CPA and other amplification technology, laser intensity achieves great increase and laser power can be high to PW(105) now, this ultrashort pulse lasers offer scientists a route to investigate laser-matter interaction in an absolute new regime.So far the researches on ultrashort pulse laser-matter interaction concentrated on infrared regime, yet ultraviolet laser has the advantage in intense field physics and ICF researches for its short wavelength and less nonlinear effects. KrF excimer is the best medium in UV ultrashort pulse amplification for its small saturation energy and high contrast ratio accessible.

  4. Genome position and gene amplification

    Czech Academy of Sciences Publication Activity Database

    Jirsová, Pavla; Snijders, A.M.; Kwek, S.; Roydasgupta, R.; Fridlyand, J.; Tokuyasu, T.; Pinkel, D.; Albertson, D. G.

    2007-01-01

    Roč. 8, č. 6 (2007), r120. ISSN 1474-760X Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : gene amplification * array comparative genomic hybridization * oncogene Subject RIV: BO - Biophysics Impact factor: 6.589, year: 2007

  5. 高效节能粗选压力筛技术%Technology on pressure coarse screen with high efficient and energy saving

    Institute of Scientific and Technical Information of China (English)

    张鹏; 王玉鹏; 毛恩礼

    2013-01-01

      Pressure coarse screen with high efficient and energy saving is a new generation of coarse screening equipment developed by Shandong Jiefeng Machinery Manufacture Co., Ltd. The key parts were developed and improved through the design of screening drum with disturbing strip, rotor with spiral cam and new technology for slurry dilution. It proved by clients’ application that this kind of pressure coarse screen has the characteristics of low energy consumption and high output.%  高效节能粗选压力筛是山东杰锋机械制造有限公司自主研发的新一代粗筛选设备。采用增设干扰条的筛鼓、螺旋式凸轮转子、独特的浆料稀释等技术手段对关键部件进行研发改进,经过客户使用证明高效节能粗选压力筛运行能耗低、产量高,优势明显。

  6. 多重连接依赖式探针扩增技术在α地中海贫血基因诊断与产前诊断中的应用%The application of multiplex ligation-dependent probe amplification technology in diagnosis and prenatal diagnosis of α-thalassemia

    Institute of Scientific and Technical Information of China (English)

    陈亚军; 杨学煌; 曾宪琪; 乔伶俐

    2013-01-01

    Objective To investigate the multiplex ligation-dependent probe amplification (MLPA) technology in the detection of gene deletion and prenatal diagnosis of α-thalassaemia.Methods Phenotypes were analyzed by whole blood cell counting and hemoglobin component detection of peripheral blood samples from the subjects.The gene deletions and point mutations of α-thalassaemia were detected with regular gap-PCR and reverse dot blot (RDB) method.At last,the MLPA method was applied for detection of α-globin gene deletion.All the prenatal diagnosis samples were detected with both gap-PCR and MLPA method.Results α-thalassaemia phenotype was found in 75 samples from 1256 (628 couples) peripheral blood samples for pre-pregnancy or prenatal thalassemia gene screening.Among them,71 samples carrying α-gene mutations and consistent with phenotypes were detected by routine methods.Inthe other 3 samples with no α-gene mutations detected and 1 sample with HbH phenotype but genotype of-α42/αα were analyzed by MLPA and found each one samples of whole α-globin gene cluster deletion,respectively.Seventeen high risk couples were screened.Among the 17 prenatal diagnosis samples,2 villus samples contaminated by exogenous DNA were confirmed by MLPA method.Conclusions MLPA is an effective complement for α-thalassaemia gene deletion detection.The molecular diagnosis strategy and process of gap-PCR combined with MLPA for α-thalassaemia gene deletion detection can prevent the missing of gene deletion,and false-positive or false-negative misdiagnosis of α-thalassaemia in prenatal diagnosis.%目的 探讨多重连接依赖式探针扩增(M LPA)技术在α地中海贫血(地贫)基因缺失检测及产前诊断中的应用.方法 采用全血细胞计数和血红蛋白成分检测对受检者外周血标本进行表型分析,采用常规跨越裂点PCR(gap-PCR)技术及反向斑点杂交(RDB)法检测α地贫基因缺失及点突变,采用MLPA技术检测α珠蛋白基因缺失;产前

  7. Vision Screening

    Science.gov (United States)

    ... offer vision screening programs for children. At what age should a child have his or her vision screened? Vision screening ... a child fails a vision screening at any age, the child should be referred for a comprehensive eye examination. ...

  8. Newborn Screening

    Science.gov (United States)

    ... Role of Laboratories Meet the Scientist Newborn Screening: Family Stories Newborn Screening: Public Health Stories Screening Newborns for Critical ... Quality Assurance Program Newborn Screening Translation Research Initiative Newborn ... Stay Connected Twitter Facebook ...

  9. Space Optical Communications Using Laser Beam Amplification

    Science.gov (United States)

    Agrawal, Govind

    2015-01-01

    The Space Optical Communications Using Laser Beam Amplification (SOCLBA) project will provide a capability to amplify a laser beam that is received in a modulating retro-reflector (MRR) located in a satellite in low Earth orbit. It will also improve the pointing procedure between Earth and spacecraft terminals. The technology uses laser arrays to strengthen the reflected laser beam from the spacecraft. The results of first year's work (2014) show amplification factors of 60 times the power of the signal beam. MMRs are mirrors that reflect light beams back to the source. In space optical communications, a high-powered laser interrogator beam is directed from the ground to a satellite. Within the satellite, the beam is redirected back to ground using the MMR. In the MMR, the beam passes through modulators, which encode a data signal onto the returning beam. MMRs can be used in small spacecraft for optical communications. The SOCLBA project is significant to NASA and small spacecraft due to its application to CubeSats for optical data transmission to ground stations, as well as possible application to spacecraft for optical data transmission.

  10. First-trimester screening in pregnancies conceived by assisted reproductive technology: significance of gestational dating by oocyte retrieval or sonographic measurement of crown-rump length

    DEFF Research Database (Denmark)

    Gjerris, A.C.; Loft, A.; Pinborg, A.;

    2008-01-01

    OBJECTIVES: To evaluate, in pregnancies conceived by assisted reproductive technology, whether determination of gestational age (GA) by date of oocyte aspiration (DOA) or crown-rump length (CRL) at first-trimester screening influences the distribution of serum and sonographic markers or the...... performance of first-trimester screening for chromosomal abnormalities. METHODS: GA was calculated using either DOA or CRL at blood sampling and nuchal translucency thickness (NT) measurement in 729 singleton pregnancies conceived by in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI......). Weight-corrected log multiples of the median (MoM) marker distributions specific for IVF pregnancy were established using multiple log regression and compared for DOA- and CRL-based GA calculation. RESULTS: GA determined by CRL was significantly larger, albeit slightly, than was GA determined by DOA...

  11. Comprehensive human genome amplification using multiple displacement amplification

    OpenAIRE

    Dean, Frank B.; Hosono, Seiyu; Fang, Linhua; Wu, Xiaohong; Faruqi, A. Fawad; Bray-Ward, Patricia; Zhenyu SUN; Zong, Qiuling; Du, Yuefen; Du, Jing; Driscoll, Mark; Song, Wanmin; Kingsmore, Stephen F.; Egholm, Michael; Lasken, Roger S.

    2002-01-01

    Fundamental to most genetic analysis is availability of genomic DNA of adequate quality and quantity. Because DNA yield from human samples is frequently limiting, much effort has been invested in developing methods for whole genome amplification (WGA) by random or degenerate oligonucleotide-primed PCR. However, existing WGA methods like degenerate oligonucleotide-primed PCR suffer from incomplete coverage and inadequate average DNA size. We describe a method, termed multi...

  12. Retrieval and Amplification of DNA from Unstained Histopathological Sections

    Institute of Scientific and Technical Information of China (English)

    DonnaC.MONTAGUE; BeverlyD.LYN-COOK; 等

    1993-01-01

    Testing of compounds for carcinogenic potential in vivo involves various experimental designs.A few of these techniques are directed to demonstrate the genotoxicity and mutagenicity of the compound by histopathology.These changes shown by histochemical means include monoclonal antibody directed cellular markers.Development of the polymerase chain reaction technique(PCR)for amplification of DNA has facilitated the investigation of molecular events related to the formation of malignant neoplasms.We describe here a method for screening tissues for mutations of the H-ras gene using monoclonal antibodies directed toward normal and mutant p21 proteins.Formalin-fixed,paraffinembedded tissue sections are used to subsequently confirm the gene mutation by PCR amplification of the H-ras gene.The results indicated a successful application of this technique to demonstrate the presence of p21 oncoprotein in the tissues tested.

  13. Debating the Desirability of New Biomedical Technologies: Lessons from the Introduction of Breast Cancer Screening in the Netherlands

    OpenAIRE

    Boenink, M.

    2011-01-01

    Health technology assessment (HTA) was developed in the 1970s and 1980s to facilitate decision making on the desirability of new biomedical technologies. Since then, many of the standard tools and methods of HTA have been criticized for their implicit normativity. At the same time research into the character of technology in practice has motivated philosophers, sociologists and anthropologists to criticize the traditional view of technology as a neutral instrument designed to perform a specif...

  14. ENVIRONMENTAL TECHNOLOGY VERIFICATION: Separation of Manure Solids from Flushed Swine Waste. Hoffland Environmental Inc. Drag Screen and Clarifier

    Science.gov (United States)

    Verification testing of the Hoffland Drag Screen and Clarifier was conducted at the North Carolina State University's Lake Wheeler Road Field Laboratory, in Raleigh, North Carolina. The farm is designed to operate as a research and teaching facility with the capacity for 250 so...

  15. Automated nucleic acid amplification testing in blood banks: An additional layer of blood safety

    Directory of Open Access Journals (Sweden)

    Pragati Chigurupati

    2015-01-01

    Full Text Available Context: A total of 30 million blood components are transfused each year in India. Blood safety thus becomes a top priority, especially with a population of around 1.23 billion and a high prevalence rate of human immunodeficiency virus (HIV, hepatitis B virus (HBV and hepatitis C virus (HCV in general population. Nucleic acid amplification testing (NAT in blood donor screening has been implemented in many developed countries to reduce the risk of transfusion-transmitted viral infections (TTIs. NAT takes care of the dynamics of window period of viruses and offers the safest blood pack for donation. Aims: The aim of this study is to show the value of NAT in blood screening. Settings and Design: Dhanavantari Blood Bank, Rajahmundry, Andhra Pradesh, India. Subjects and Methods: Over a period of 1 year from January 2012 to December 2012, a total number of 15,000 blood donor samples were subjected to tests for HIV, HBV, and HCV by enzyme-linked immunosorbent assay (ELISA method and 8000 ELISA nonreactive samples were subjected for NAT using multiplex polymerase chain reaction technology. Results: Of the 15,000 donors tested, 525 were seroreactive. In 8000 ELISA negative blood samples subjected to NAT, 4 donor samples were reactive for HBV. The NAT yield was 1 in 2000. Conclusions: NAT could detect HIV, HBV, and HCV cases in blood donor samples those were undetected by serological tests. NAT could interdict 2500 infectious donations among our approximate 5 million annual blood donations.

  16. 快速筛选技术的评价验证%Development and application of rapid screening technology and its evaluation and authentication profiles

    Institute of Scientific and Technical Information of China (English)

    赵博; 张庆合; 李红梅

    2014-01-01

    Rapid screening technology means, including sample preparation, a kind of technology to be able to issue the test results in a short time. It was also defined as rapid detection technology. It was mainly used in food, pesticide, veterinary drug residues, microbial pathogens, nutrients, and unknown contaminants, etc. Rapid screening technology had become the focus of research as well as the food safety in our country. Several technologies of the rapid screening method were mainly introduced, including molecular spectrometry, immunoassay, enzyme inhibition method, and biological sensors,etc. With the continuous development of rapid screening technology, rapid detection methods and related equipment products appeared more and more, and their quality control and validation method turned to be particularly important. In this paper, the development and application of the rapid screening technology in food safety were expounded as well as its evaluation methods. Its main technical parameters included sensitivity, the accuracy of the negative and positive threshold, selectivity and specificity, detection limit, quantitative limit, repeatability and reproducibility, etc. The development in the future was prospected as well.%快速筛选技术是指包括样品制备在内,能够在较短时间内出具检测结果的行为,也称之为快速检测技术。随着我国食品安全问题广受关注,快速筛选技术便成为研究的重点。快速检测目前主要应用于食品中农、兽药残留,微生物致病菌,营养成分,不明污染物等针对食品安全的现场快速检测及常规检测。本文介绍了分子光谱法、免疫分析方法、酶抑制法和生物传感器等几种快速筛选技术的研究进展以及在食品安全检测等领域的应用。随着快速筛选技术的不断发展使得快速检测方法及其相关仪器产品种类越来越多且原理复杂,快速检测方法的质量控制和方法验证显得尤为重

  17. Development and application of rapid screening technology and its evaluation and authentication profiles%快速筛选技术的评价验证

    Institute of Scientific and Technical Information of China (English)

    赵博; 张庆合; 李红梅

    2014-01-01

    快速筛选技术是指包括样品制备在内,能够在较短时间内出具检测结果的行为,也称之为快速检测技术。随着我国食品安全问题广受关注,快速筛选技术便成为研究的重点。快速检测目前主要应用于食品中农、兽药残留,微生物致病菌,营养成分,不明污染物等针对食品安全的现场快速检测及常规检测。本文介绍了分子光谱法、免疫分析方法、酶抑制法和生物传感器等几种快速筛选技术的研究进展以及在食品安全检测等领域的应用。随着快速筛选技术的不断发展使得快速检测方法及其相关仪器产品种类越来越多且原理复杂,快速检测方法的质量控制和方法验证显得尤为重要。本文重点阐述了快速筛选技术与方法的评价验证,其主要技术参数包括:敏感度、阴性和阳性界限值的准确性、选择性和特异性、检出限、定量限、重复性和再现性等,并对其发展前景进行了展望。%Rapid screening technology means, including sample preparation, a kind of technology to be able to issue the test results in a short time. It was also defined as rapid detection technology. It was mainly used in food, pesticide, veterinary drug residues, microbial pathogens, nutrients, and unknown contaminants, etc. Rapid screening technology had become the focus of research as well as the food safety in our country. Several technologies of the rapid screening method were mainly introduced, including molecular spectrometry, immunoassay, enzyme inhibition method, and biological sensors,etc. With the continuous development of rapid screening technology, rapid detection methods and related equipment products appeared more and more, and their quality control and validation method turned to be particularly important. In this paper, the development and application of the rapid screening technology in food safety were expounded as well as its evaluation methods

  18. Isothermal amplification detection of nucleic acids by a double-nicked beacon.

    Science.gov (United States)

    Shi, Chao; Zhou, Meiling; Pan, Mei; Zhong, Guilin; Ma, Cuiping

    2016-03-01

    Isothermal and rapid amplification detection of nucleic acids is an important technology in environmental monitoring, foodborne pathogen detection, and point-of-care clinical diagnostics. Here we have developed a novel method of isothermal signal amplification for single-stranded DNA (ssDNA) detection. The ssDNA target could be used as an initiator, coupled with a double-nicked molecular beacon, to originate amplification cycles, achieving cascade signal amplification. In addition, the method showed good specificity and strong anti-jamming capability. Overall, it is a one-pot and isothermal strand displacement amplification method without the requirement of a stepwise procedure, which greatly simplifies the experimental procedure and decreases the probability of contamination of samples. With its advantages, the method would be very useful to detect nucleic acids in point-of-care or field use. PMID:26706801

  19. Diversity of Phage-Displayed Libraries of Peptides during Panning and Amplification

    Directory of Open Access Journals (Sweden)

    Mohammad R. Jafari

    2011-02-01

    Full Text Available The amplification of phage-displayed libraries is an essential step in the selection of ligands from these libraries. The amplification of libraries, however, decreases their diversity and limits the number of binding clones that a screen can identify. While this decrease might not be a problem for screens against targets with a single binding site (e.g., proteins, it can severely hinder the identification of useful ligands for targets with multiple binding sites (e.g., cells. This review aims to characterize the loss in the diversity of libraries during amplification. Analysis of the peptide sequences obtained in several hundred screens of peptide libraries shows explicitly that there is a significant decrease in library diversity that occurs during the amplification of phage in bacteria. This loss during amplification is not unique to specific libraries: it is observed in many of the phage display systems we have surveyed. The loss in library diversity originates from competition among phage clones in a common pool of bacteria. Based on growth data from the literature and models of phage growth, we show that this competition originates from growth rate differences of only a few percent for different phage clones. We summarize the findings using a simple two-dimensional “phage phase diagram”, which describes how the collapse of libraries, due to panning and amplification, leads to the identification of only a subset of the available ligands. This review also highlights techniques that allow elimination of amplification-induced losses of diversity, and how these techniques can be used to improve phage-display selection and enable the identification of novel ligands.

  20. Detection of Clostridium perfringens alpha toxin gene in lambs by loop mediated isothermal amplification

    OpenAIRE

    B. Radhika; N. Vinod Kumar; Sreenivasulu, D.

    2016-01-01

    Aim: The loop mediated isothermal amplification (LAMP) was standardized for rapid detection of Clostridium perfringens. Materials and Methods: A total of 120 fecal samples were collected from enterotoxemia suspected lambs were used for screening of C. perfringens cpa gene by LAMP. The specificity of the LAMP amplified products was tested by digesting with restriction enzyme XmnI for alpha toxin gene. Results: Out of 120 samples screened 112 (93.3%) samples were positive by both LAMP and polym...

  1. Preliminary screening of alternative technologies to incineration for treatment of chemical-agent-contaminated soil, Rocky Mountain Arsenal

    Energy Technology Data Exchange (ETDEWEB)

    Shem, L.M.; Rosenblatt, D.H.; Smits, M.P.; Wilkey, P.L.; Ballou, S.W.

    1995-12-01

    In support of the U.S. Army`s efforts to determine the best technologies for remediation of soils, water, and structures contaminated with pesticides and chemical agents, Argonne National Laboratory has reviewed technologies for treating soils contaminated with mustard, lewisite, sarin, o-ethyl s-(2- (diisopropylamino)ethyl)methyl-phosphonothioate (VX), and their breakdown products. This report focuses on assessing alternatives to incineration for dealing with these contaminants. For each technology, a brief description is provided, its suitability and constraints on its use are identified, and its overall applicability for treating the agents of concern is summarized. Technologies that merit further investigation are identified.

  2. 高速筛选技术在组合催化中的应用%The applications of high-speed screening technology in combinatorial catalyst

    Institute of Scientific and Technical Information of China (English)

    李雪辉; 黄仲涛

    2001-01-01

    Many types of reactors using high-speed screening technology to study combination catalysis were introduced,including infrared temperature recording reactors,fluorescent detecting reactors,and the reactor using REMPI technology (resonance-enhanced multiphoton ionization), etc.%介绍了近年用于组合催化技术研究中的几种使用高速筛选技术的反应器,包括红外温度记录型反应器、荧光检测型反应器、利用共振强化多光子离子化技术的反应器等等。

  3. Advanced field shimming technology to reduce the influence of a screening current in a REBCO coil for a high-resolution NMR magnet

    Science.gov (United States)

    Iguchi, S.; Piao, R.; Hamada, M.; Matsumoto, S.; Suematsu, H.; Takao, T.; Saito, A. T.; Li, J.; Nakagome, H.; Jin, X.; Takahashi, M.; Maeda, H.; Yanagisawa, Y.

    2016-04-01

    This paper describes a field shimming technology to obtain a spatially homogeneous magnetic field required for a high-resolution nuclear magnetic resonance (NMR) magnet under the influence of a screening current in a (RE)Ba2Cu3O7-x (REBCO) coil. Use of REBCO inner coils is one solution to realize a super-high field (>23.5 T, 1 GHz) NMR magnet. However, a REBCO coil generates a large amount of field error harmonics due to the inhomogeneous coil winding introduced by a thin tape conductor. In addition, the performance of a field correction coil and outer superconducting (SC) shim coils are significantly reduced due to the shielding effect of the screening current in the REBCO coil. Therefore, conventional shimming technology using SC shim coils and room temperature shim coils cannot adequately compensate those field error harmonics and high-resolution NMR measurements are not possible. In the present paper, an advanced field shimming technology including an inner SC shim coil and a novel type of ferromagnetic shim were installed in a 400 MHz low-temperature SC/REBCO NMR magnet. The inner SC shim coil and the ferromagnetic shim compensated for the reduction in the performances of the field correction coil and the SC shim coils, respectively. The field error harmonics were greatly compensated with the technology and a high NMR resolution <0.01 ppm was obtained. The results from the present work suggest an optimal shimming procedure for a super-high field NMR magnet with high-temperature superconductors inner coils, i.e. the best mix of shims.

  4. Debating the desirability of new biomedical technologies: Lessons from the introduction of breast cancer screening in the Netherlands.

    NARCIS (Netherlands)

    Boenink, M.

    2012-01-01

    Health technology assessment (HTA) was developed in the 1970s and 1980s to facilitate decision making on the desirability of new biomedical technologies. Since then, many of the standard tools and methods of HTA have been criticized for their implicit normativity. At the same time research into the

  5. Health Screening

    Science.gov (United States)

    Screenings are tests that look for diseases before you have symptoms. Screening tests can find diseases early, when they're easier to treat. You can get some screenings in your doctor's office. Others need special equipment, ...

  6. Application of sequence-independent amplification to screen for potentially viral pathogens from clinical respiratory samples of children with acute respiratory tract infection of unknown etiology%应用序列非依赖扩增技术检测儿童呼吸道标本中潜在病毒病原体

    Institute of Scientific and Technical Information of China (English)

    郭英; 钱渊; 段招军

    2012-01-01

    目的 应用序列非依赖扩增技术(sequence-independent amplification,SIA)检测常见病毒筛查阴性的5岁以下急性呼吸道感染患儿的呼吸道标本中可能存在的潜在病毒病原体,了解SIA扩增文库中各种背景核酸的组成.方法 随机选择45份常见病毒筛查阴性的5岁以下急性呼吸道感染患儿的鼻咽吸出物,0.45μm过滤和DNase/RNase处理去除病毒颗粒外的各种外源性核酸,再通过序列非依赖扩增技术对处理后的标本提取的核酸进行扩增,继而对扩增产物进行克隆、测序和BLAST比对.结果 测序403个克隆,获得有效序列368个,检出16个(16/368,4.3%)真核病毒同源序列,分别与Torque teno mini virus,Torque teno midi virus和Human bocavirus同源.此外,还检出1个真菌病毒( sclerotinia sclerotiorum hypovirulence associated DNA virus 1)同源序列和5个细菌病毒(噬菌体)同源序列.其余检出序列包含206个( 206/368,56.0%)与人基因组DNA同源的序列,11个(11/368,3.0%) rRNA同源序列,72个(72/368,19.6%)细菌同源序列,4个(4/368,1.1%)真菌同源序列,5个(5/368,1.4%)寄生虫同源序列,6个(6/368,1.6%)食源性序列,以及36个(36/368,9.8%)未能确定分类的序列.结论 核酸消化结合SIA方法可以检出常规检测方法所无法检出的潜在病毒病原体,本研究为后续系统性的查找和监测未知病毒提供了基础.%Objective Application of sequence-independent amplification (SIA) to identify the potentially viral pathogens in the clinical respiratory samples of children with acute respiratory tract infection of unknown etiology and characterize the composition of various non-viral sequences in the library of SIA amplicons.Method 45 randomly selected pediatric nasopharyngeal aspirate(NPA) samples for which no causal agent could be identified by common viruses screening were subjected to filtration & DNase/RNase treatments to remove the non-viral nucleic acid and then followed by

  7. Solid-state Raman image amplification

    Science.gov (United States)

    Calmes, Lonnie Kirkland

    Amplification of low-light-level optical images is important for extending the range of lidar systems that image and detect objects in the atmosphere and underwater. The use of range-gating to produce images of particular range bins is also important in minimizing the image degradation due to light that is scattered backward from aerosols, smoke, or water along the imaging path. For practical lidar systems that must be operated within sight of unprotected observers, eye safety is of the utmost importance. This dissertation describes a new type of eye-safe, range-gated lidar sensing element based on Solid-state Raman Image Amplification (SSRIA) in a solid- state optical crystal. SSRIA can amplify low-level images in the eye-safe infrared at 1.556 μm with gains up to 106 with the addition of only quantum- limited noise. The high gains from SSRIA can compensate for low quantum efficiency detectors and can reduce the need for detector cooling. The range-gate of SSRIA is controlled by the pulsewidth of the pump laser and can be as short as 30-100 cm, using pump pulses of 2-6.7 nsec FWHM. A rate equation theoretical model is derived to help in the design of short pulsed Raman lasers. A theoretical model for the quantum noise properties of SSRIA is presented. SSRIA results in higher SNR images throughout a broad range of incident light levels, in contrast to the increasing noise factor with reduced gain in image intensified CCD's. A theoretical framework for the optical resolution of SSRIA is presented and it is shown that SSRIA can produce higher resolution than ICCD's. SSRIA is also superior in rejecting unwanted sunlight background, further increasing image SNR. Lastly, SSRIA can be combined with optical pre-filtering to perform optical image processing functions such as high-pass filtering and automatic target detection/recognition. The application of this technology to underwater imaging, called Marine Raman Image Amplification (MARIA) is also discussed. MARIA

  8. Heralded amplification of photonic qubits.

    Science.gov (United States)

    Bruno, Natalia; Pini, Vittorio; Martin, Anthony; Verma, Varun B; Nam, Sae Woo; Mirin, Richard; Lita, Adriana; Marsili, Francesco; Korzh, Boris; Bussières, Félix; Sangouard, Nicolas; Zbinden, Hugo; Gisin, Nicolas; Thew, Rob

    2016-01-11

    We demonstrate postselection free heralded qubit amplification for Time-Bin qubits and single photon states in an all-fibre, telecom-wavelength, scheme that highlights the simplicity, stability and potential for fully integrated photonic solutions. Exploiting high-efficiency superconducting detectors, the gain, fidelity and the performance of the amplifier are studied as a function of loss. We also demonstrate the first heralded single photon amplifier with independent sources. This provides a significant advance towards demonstrating device-independent quantum key distribution as well as fundamental tests of quantum mechanics over extended distances. PMID:26832244

  9. Resonant primordial gravitational waves amplification

    Directory of Open Access Journals (Sweden)

    Chunshan Lin

    2016-01-01

    Full Text Available We propose a mechanism to evade the Lyth bound in models of inflation. We minimally extend the conventional single-field inflation model in general relativity (GR to a theory with non-vanishing graviton mass in the very early universe. The modification primarily affects the tensor perturbation, while the scalar and vector perturbations are the same as the ones in GR with a single scalar field at least at the level of linear perturbation theory. During the reheating stage, the graviton mass oscillates coherently and leads to resonant amplification of the primordial tensor perturbation. After reheating the graviton mass vanishes and we recover GR.

  10. Telomerase Repeated Amplification Protocol (TRAP)

    Science.gov (United States)

    Mender, Ilgen; Shay, Jerry W.

    2016-01-01

    Telomeres are found at the end of eukaryotic linear chromosomes, and proteins that bind to telomeres protect DNA from being recognized as double-strand breaks thus preventing end-to-end fusions (Griffith et al., 1999). However, due to the end replication problem and other factors such as oxidative damage, the limited life span of cultured cells (Hayflick limit) results in progressive shortening of these protective structures (Hayflick and Moorhead, 1961; Olovnikov, 1973). The ribonucleoprotein enzyme complex telomerase-consisting of a protein catalytic component hTERT and a functional RNA component hTR or hTERC- counteracts telomere shortening by adding telomeric repeats to the end of chromosomes in ~90% of primary human tumors and in some transiently proliferating stem-like cells (Shay and Wright, 1996; Shay and Wright, 2001). This results in continuous proliferation of cells which is a hallmark of cancer. Therefore, telomere biology has a central role in aging, cancer progression/metastasis as well as targeted cancer therapies. There are commonly used methods in telomere biology such as Telomere Restriction Fragment (TRF) (Mender and Shay, 2015b), Telomere Repeat Amplification Protocol (TRAP) and Telomere dysfunction Induced Foci (TIF) analysis (Mender and Shay, 2015a). In this detailed protocol we describe Telomere Repeat Amplification Protocol (TRAP). The TRAP assay is a popular method to determine telomerase activity in mammalian cells and tissue samples (Kim et al., 1994). The TRAP assay includes three steps: extension, amplification, and detection of telomerase products. In the extension step, telomeric repeats are added to the telomerase substrate (which is actually a non telomeric oligonucleotide, TS) by telomerase. In the amplification step, the extension products are amplified by the polymerase chain reaction (PCR) using specific primers (TS upstream primer and ACX downstream primer) and in the detection step, the presence or absence of telomerase is

  11. Dynamics and Control of DNA Sequence Amplification

    CERN Document Server

    Marimuthu, Karthikeyan

    2014-01-01

    DNA amplification is the process of replication of a specified DNA sequence \\emph{in vitro} through time-dependent manipulation of its external environment. A theoretical framework for determination of the optimal dynamic operating conditions of DNA amplification reactions, for any specified amplification objective, is presented based on first-principles biophysical modeling and control theory. Amplification of DNA is formulated as a problem in control theory with optimal solutions that can differ considerably from strategies typically used in practice. Using the Polymerase Chain Reaction (PCR) as an example, sequence-dependent biophysical models for DNA amplification are cast as control systems, wherein the dynamics of the reaction are controlled by a manipulated input variable. Using these control systems, we demonstrate that there exists an optimal temperature cycling strategy for geometric amplification of any DNA sequence and formulate optimal control problems that can be used to derive the optimal tempe...

  12. A high-throughput liquid bead array-based screening technology for Bt presence in GMO manipulation.

    Science.gov (United States)

    Fu, Wei; Wang, Huiyu; Wang, Chenguang; Mei, Lin; Lin, Xiangmei; Han, Xueqing; Zhu, Shuifang

    2016-03-15

    The number of species and planting areas of genetically modified organisms (GMOs) has been rapidly developed during the past ten years. For the purpose of GMO inspection, quarantine and manipulation, we have now devised a high-throughput Bt-based GMOs screening method based on the liquid bead array. This novel method is based on the direct competitive recognition between biotinylated antibodies and beads-coupled antigens, searching for Bt presence in samples if it contains Bt Cry1 Aa, Bt Cry1 Ab, Bt Cry1 Ac, Bt Cry1 Ah, Bt Cry1 B, Bt Cry1 C, Bt Cry1 F, Bt Cry2 A, Bt Cry3 or Bt Cry9 C. Our method has a wide GMO species coverage so that more than 90% of the whole commercialized GMO species can be identified throughout the world. Under our optimization, specificity, sensitivity, repeatability and availability validation, the method shows a high specificity and 10-50 ng/mL sensitivity of quantification. We then assessed more than 1800 samples in the field and food market to prove capacity of our method in performing a high throughput screening work for GMO manipulation. Our method offers an applicant platform for further inspection and research on GMO plants. PMID:26499065

  13. Modelling and Managing SSD Write-amplification

    OpenAIRE

    Dayan, Niv; Bouganim, Luc; Bonnet, Philippe

    2015-01-01

    How stable is the performance of your flash-based Solid State Drives (SSDs)? This question is central for database designers and administrators, cloud service providers, and SSD constructors. The answer depends on write-amplification, i.e., garbage collection overhead. More specifically, the answer depends on how write-amplification evolves in time. How then can one model and manage write-amplification, especially when application workloads change? This is the focus of this paper. Managing wr...

  14. Parasitic bipolar amplification in a single event transient and its temperature dependence

    Institute of Scientific and Technical Information of China (English)

    Liu Zheng; Chen Shu-Ming; Chen Jian-Jun; Qin Jun-Rui; Liu Rong-Rong

    2012-01-01

    Using three-dimensional technology computer-aided design (TCAD) simulation,parasitic bipolar amplification in a single event transient (SET) current of a single transistor and its temperature dependence are studied.We quantify the contributions of different current components in a SET current pulse,and it is found that the proportion of parasitic bipolar amplification in total collected charge is about 30% in both 130-nm and 90-nm technologies.The temperature dependence of parasitic bipolar amplification and the mechanism of the SET pulse are also investigated and quantified.The results show that the proportion of charge induced by parasitic bipolar increases with rising temperature,which illustrates that the parasitic bipolar amplification plays an important role in the charge collection of a single transistor.

  15. Parasitic bipolar amplification in a single event transient and its temperature dependence

    International Nuclear Information System (INIS)

    Using three-dimensional technology computer-aided design (TCAD) simulation, parasitic bipolar amplification in a single event transient (SET) current of a single transistor and its temperature dependence are studied. We quantify the contributions of different current components in a SET current pulse, and it is found that the proportion of parasitic bipolar amplification in total collected charge is about 30% in both 130-nm and 90-nm technologies. The temperature dependence of parasitic bipolar amplification and the mechanism of the SET pulse are also investigated and quantified. The results show that the proportion of charge induced by parasitic bipolar increases with rising temperature, which illustrates that the parasitic bipolar amplification plays an important role in the charge collection of a single transistor

  16. Dynamics and control of DNA sequence amplification

    International Nuclear Information System (INIS)

    DNA amplification is the process of replication of a specified DNA sequence in vitro through time-dependent manipulation of its external environment. A theoretical framework for determination of the optimal dynamic operating conditions of DNA amplification reactions, for any specified amplification objective, is presented based on first-principles biophysical modeling and control theory. Amplification of DNA is formulated as a problem in control theory with optimal solutions that can differ considerably from strategies typically used in practice. Using the Polymerase Chain Reaction as an example, sequence-dependent biophysical models for DNA amplification are cast as control systems, wherein the dynamics of the reaction are controlled by a manipulated input variable. Using these control systems, we demonstrate that there exists an optimal temperature cycling strategy for geometric amplification of any DNA sequence and formulate optimal control problems that can be used to derive the optimal temperature profile. Strategies for the optimal synthesis of the DNA amplification control trajectory are proposed. Analogous methods can be used to formulate control problems for more advanced amplification objectives corresponding to the design of new types of DNA amplification reactions

  17. Dynamics and control of DNA sequence amplification

    Energy Technology Data Exchange (ETDEWEB)

    Marimuthu, Karthikeyan [Department of Chemical Engineering and Center for Advanced Process Decision-Making, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Chakrabarti, Raj, E-mail: raj@pmc-group.com, E-mail: rajc@andrew.cmu.edu [Department of Chemical Engineering and Center for Advanced Process Decision-Making, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Division of Fundamental Research, PMC Advanced Technology, Mount Laurel, New Jersey 08054 (United States)

    2014-10-28

    DNA amplification is the process of replication of a specified DNA sequence in vitro through time-dependent manipulation of its external environment. A theoretical framework for determination of the optimal dynamic operating conditions of DNA amplification reactions, for any specified amplification objective, is presented based on first-principles biophysical modeling and control theory. Amplification of DNA is formulated as a problem in control theory with optimal solutions that can differ considerably from strategies typically used in practice. Using the Polymerase Chain Reaction as an example, sequence-dependent biophysical models for DNA amplification are cast as control systems, wherein the dynamics of the reaction are controlled by a manipulated input variable. Using these control systems, we demonstrate that there exists an optimal temperature cycling strategy for geometric amplification of any DNA sequence and formulate optimal control problems that can be used to derive the optimal temperature profile. Strategies for the optimal synthesis of the DNA amplification control trajectory are proposed. Analogous methods can be used to formulate control problems for more advanced amplification objectives corresponding to the design of new types of DNA amplification reactions.

  18. Advantages of combined touch screen technology and text hyperlink for the pathology grossing manual: a simple approach to access instructive information in biohazardous environments.

    Science.gov (United States)

    Qu, Zhenhong; Ghorbani, Rhonda P; Li, Hongyan; Hunter, Robert L; Hannah, Christina D

    2007-03-01

    Gross examination, encompassing description, dissection, and sampling, is a complex task and an essential component of surgical pathology. Because of the complexity of the task, standardized protocols to guide the gross examination often become a bulky manual that is difficult to use. This problem is further compounded by the high specimen volume and biohazardous nature of the task. As a result, such a manual is often underused, leading to errors that are potentially harmful and time consuming to correct-a common chronic problem affecting many pathology laboratories. To combat this problem, we have developed a simple method that incorporates complex text and graphic information of a typical procedure manual and yet allows easy access to any intended instructive information in the manual. The method uses the Object-Linking-and-Embedding function of Microsoft Word (Microsoft, Redmond, WA) to establish hyperlinks among different contents, and then it uses the touch screen technology to facilitate navigation through the manual on a computer screen installed at the cutting bench with no need for a physical keyboard or a mouse. It takes less than 4 seconds to reach any intended information in the manual by 3 to 4 touches on the screen. A 3-year follow-up study shows that this method has increased use of the manual and has improved the quality of gross examination. The method is simple and can be easily tailored to different formats of instructive information, allowing flexible organization, easy access, and quick navigation. Increased compliance to instructive information reduces errors at the grossing bench and improves work efficiency. PMID:17188327

  19. Approaches towards molecular amplification for sensing.

    Science.gov (United States)

    Goggins, Sean; Frost, Christopher G

    2016-06-01

    Diagnostic assays that rely on molecular interactions have come a long way; from initial reversible detection systems towards irreversible reaction indicator-based methods. More recently, the emergence of innovative molecular amplification methodologies has revolutionised sensing, allowing diagnostic assays to achieve ultra-low limits of detection. There have been a significant number of molecular amplification approaches developed over recent years to accommodate the wide variety of analytes that require sensitive detection. To celebrate this achievement, this comprehensive critical review has been compiled to give a broad overview of the many different approaches used to attain amplification in sensing with an aim to inspire the next generation of diagnostic assays looking to achieve the ultimate detection limit. This review has been created with the focus on how each conceptually unique molecular amplification methodology achieves amplification, not just its sensitivity, while highlighting any key processes. Excluded are any references that were not found to contain an obvious molecular amplifier or amplification component, or that did not use an appropriate signal readout that could be incorporated into a sensing application. Additionally, methodologies where amplification is achieved through advances in instrumentation are also excluded. Depending upon the type of approach employed, amplification strategies are divided into four categories: target, label, signal or receptor amplification. More recent, more complex protocols combine a number of approaches and are therefore categorised by which amplification component described within was considered as the biggest advancement. The advantages and disadvantages of each methodology are discussed along with any limits of detection, if stated in the original article. Any subsequent use of the methodology within sensing or any other application is also mentioned to draw attention to its practicality. The importance of

  20. Gene Technology: Also a Gender Issue. Views of Dutch Informed Women on Genetic Screening and Gene Therapy.

    Science.gov (United States)

    van Berkel, Dymphie; Klinge, Ineke

    1997-01-01

    The views of Dutch women on the implications of the analysis of the human genome were studied by questionnaire and interview. Although a serious lack of knowledge about the topic was found, interviews produced a broad range of problematic issues. Attention to gender implications of gene technology is needed. (Author/EMK)

  1. Cost-effectiveness of quantitative ultrasound as a technique for screening of osteoporotic fracture risk: report on a health technology assessment conducted in 2001

    Directory of Open Access Journals (Sweden)

    Wasem, Jürgen

    2004-03-01

    Full Text Available Aim: On behalf of the German Agency for Health Technology Assessment (DAHTA@DIMDI a rapid economic HTA was conducted. Aim of the HTA was to evaluate the cost-effectiveness of quantitative ultrasound (QUS for screening of osteoporotic fracture risk. Study population was formed by postmenopausal women. QUS was compared to the dual X-ray absorptiometry (DXA as the most frequently used method of measurement. Methods: According to the recommendations for rapid economic HTA a comprehensive literature search was conducted. Data of identified and relevant publications have been extracted in form of a qualitative and quantitative information synthesis. The authors calculated incremental cost-effectiveness ratios for different screening procedures: (1 one-step proceeding comparing QUS with DXA, (2 two-step proceeding starting with QUS followed by DXA in pathologic cases. Results: An additional case diagnosed by DXA in a one-step proceeding rises additional costs of about 1,000 EURO. A two-step proceeding with QUS is cost-effective as long as the costs of one QUS examination are lower than 31%-51% of the costs of one DXA examination. Discussion: All considered studies showed methodological limitations. None of them included long term effects like avoided bone fractures. Considering long-term effects probably would change the results. Due to the weakness of data no concluding judgement about the cost-effectiveness of QUS can be given.

  2. Detection of Chromosomal Structural Alterations in Single Cells by SNP Arrays: A Systematic Survey of Amplification Bias and Optimized Workflow

    Science.gov (United States)

    Iwamoto, Kazuya; Bundo, Miki; Ueda, Junko; Nakano, Yoko; Ukai, Wataru; Hashimoto, Eri; Saito, Toshikazu; Kato, Tadafumi

    2007-01-01

    Background In single-cell human genome analysis using whole-genome amplified product, a strong amplification bias involving allele dropout and preferential amplification hampers the quality of results. Using an oligonucleotide single nucleotide polymorphism (SNP) array, we systematically examined the nature of this amplification bias, including frequency, degree, and preference for genomic location, and we assessed the effects of this amplification bias on subsequent genotype and chromosomal copy number analyses. Methodology/Principal Findings We found a large variability in amplification bias among the amplified products obtained by multiple displacement amplification (MDA), and this bias had a severe effect on the genotype and chromosomal copy number analyses. We established optimal experimental conditions for pre-screening for high-quality amplified products, processing array data, and analyzing chromosomal structural alterations. Using this optimized protocol, we successfully detected previously unidentified chromosomal structural alterations in single cells from a lymphoblastoid cell line. These alterations were subsequently confirmed by karyotype analysis. In addition, we successfully obtained reproducible chromosomal copy number profiles of single cells from the cell line with a complex karyotype, indicating the applicability and potential of our optimized workflow. Conclusions/Significance Our results suggest that the quality of amplification products should be critically assessed before using them for genomic analyses. The method of MDA-based whole-genome amplification followed by SNP array analysis described here will be useful for exploring chromosomal alterations in single cells. PMID:18074030

  3. Tsunami Amplification due to Focusing

    Science.gov (United States)

    Moore, C. W.; Kanoglu, U.; Titov, V. V.; Aydin, B.; Spillane, M. C.; Synolakis, C. E.

    2012-12-01

    Tsunami runup measurements over the periphery of the Pacific Ocean after the devastating Great Japan tsunami of 11 March 2011 showed considerable variation in far-field and near-field impact. This variation of tsunami impact have been attributed to either directivity of the source or by local topographic effects. Directivity arguments alone, however, cannot explain the complexity of the radiated patterns in oceans with trenches and seamounts. Berry (2007, Proc. R. Soc. Lond. A 463, 3055-3071) discovered how such underwater features may concentrate tsunamis into cusped caustics and thus cause large local amplifications at specific focal points. Here, we examine focusing and local amplification, not by considering the effects of underwater diffractive lenses, but by considering the details of the dipole nature of the initial profile, and propose that certain regions of coastline are more at-risk, not simply because of directivity but because typical tsunami deformations create focal regions where abnormal tsunami wave height can be registered (Marchuk and Titov, 1989, Proc. IUGG/IOC International Tsunami Symposium, Novosibirsk, USSR). In this work, we present a new general analytical solution of the linear shallow-water wave equation for the propagation of a finite-crest-length source over a constant depth without any restriction on the initial profile. Unlike the analytical solution of Carrier and Yeh (2005, Comp. Mod. Eng. & Sci. 10(2), 113-121) which was restricted to initial conditions with Gaussian profiles and involved approximation, our solution is not only exact, but also general and allows the use of realistic initial waveform such as N-waves as defined by Tadepalli and Synolakis (1994, Proc. R. Soc. Lond. A 445, 99-112). We then verify our analytical solution for several typical wave profiles, both with the NOAA tsunami forecast model MOST (Titov and Synolakis, 1998, J. Waterw. Port Coast. Ocean Eng. 124(4), 157-171) which is validated and verified through

  4. HER2 immunohistochemistry significantly overestimates HER2 amplification in uterine papillary serous carcinomas.

    Science.gov (United States)

    Mentrikoski, Mark J; Stoler, Mark H

    2014-06-01

    Recently, there have been numerous reports showing that HER2 overexpression or amplification occurs in a variable number of uterine papillary serous carcinoma (UPSC) cases, leading to a current clinical trial targeting this pathway. Although approved algorithms exist for scoring HER2 overexpression/amplification in breast and gastroesophageal carcinomas, scoring criteria and the optimal methodology for assessing HER2 in UPSC are currently unknown. Most frequently, the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) breast carcinoma algorithms have been utilized for UPSC, wherein cases are screened with immunohistochemistry (IHC), followed by fluorescence in situ hybridization for equivocal cases. However, interpreting HER2 IHC can be prone to significant subjectivity, often leading to false-positive results. To better correlate HER2 IHC results with underlying amplification in UPSC, we compared HER2 overexpression by IHC with HER2 amplification with chromogenic in situ hybridization (CISH). A total of 69 cases of UPSC-57 pure and 12 mixed-were identified over a 10-year period. All were included in a tissue microarray, and HER2 IHC and CISH were performed. Each case was scored according to the most recent 2013, as well as the 2007, ASCO/CAP scoring guidelines for breast carcinoma. Whole-tissue sections were also examined in cases with amplification by CISH on initial screening, as well as an equal number of negative cases, to account for intratumoral heterogeneity. Nine (13%) cases showed HER2 amplification by CISH, whereas 14 (20%) and 28 (40%) cases showed overexpression with IHC when the 2007 or 2013 ASCO/CAP criteria were utilized, respectively. The overall concordance rate between CISH and IHC was 64% (9/14) with the 2007 ASCO/CAP criteria and 32% (9/28) with the 2013 ASCO/CAP criteria. Intratumoral heterogeneity was seen in 3 (33%) amplified cases. No additional amplified cases were identified on subsequent whole

  5. Mechanisms of metal-induced centrosome amplification.

    Science.gov (United States)

    Holmes, Amie L; Wise, John Pierce

    2010-12-01

    Exposure to toxic and carcinogenic metals is widespread; however, their mechanisms of action remain largely unknown. One potential mechanism for metal-induced carcinogenicity and toxicity is centrosome amplification. Here we review the mechanisms for metal-induced centrosome amplification, including arsenic, chromium, mercury and nano-titanium dioxide. PMID:21118148

  6. Mechanisms of Metal-Induced Centrosome Amplification

    OpenAIRE

    Holmes, Amie L.; Wise, John Pierce

    2010-01-01

    Exposure to toxic and carcinogenic metals is widespread; however, their mechanisms of action remain largely unknown. One potential mechanism for metal-induced carcinogenicity and toxicity is centrosome amplification. Here, we review the mechanisms for metal-induced centrosome amplification, including arsenic, chromium, mercury and nano-titanium dioxide.

  7. E-recruitment and Applicant Tracking System : New age of technology based applicant screening. Threat or opportunity?

    OpenAIRE

    Gagua, Levan

    2015-01-01

    The purpose of this study was to provide reader with in-depth information of new technological instruments, which recruiters apply in order mitigate application data. This study examines how applicant tracking system has integrated in Finnish organizations´ human resource department and how it helps managing labour force. This case study was executed in nature of qualitative research, where subjected organizations were interviewed via telephone and e-mail conversations. Findings wer...

  8. A Rapid Screening Analysis of Antioxidant Compounds in Native Australian Food Plants Using Multiplexed Detection with Active Flow Technology Columns

    Directory of Open Access Journals (Sweden)

    Emmanuel Janaka Rochana Rupesinghe

    2016-01-01

    Full Text Available Conventional techniques for identifying antioxidant and phenolic compounds in native Australian food plants are laborious and time-consuming. Here, we present a multiplexed detection technique that reduces analysis time without compromising separation performance. This technique is achieved using Active Flow Technology-Parallel Segmented Flow (AFT-PSF columns. Extracts from cinnamon myrtle (Backhousia myrtifolia and lemon myrtle (Backhousia citriodora leaves were analysed via multiplexed detection using an AFT-PSF column with underivatised UV-VIS, mass spectroscopy (MS, and the 2,2-diphenyl-1-picrylhydrazyl (DPPH• derivatisation for antioxidants as detection methods. A number of antioxidant compounds were detected in the extracts of each leaf extract.

  9. Neonatal screening.

    Science.gov (United States)

    Pàmpols, Teresa

    2003-01-01

    Neonatal screening (NS) is a medical act in the context of preventive medicine aimed at the early identification of infants affected by certain conditions that threaten their life and long-term health, for which a timely intervention can lead to a significant reduction of morbidity, mortality and associated disabilities. It emerged three decades ago in the context of prevention of mental retardation. Since then, around 600 inborn metabolic disorders have been described and technological progress has been impressive; nevertheless only around 5% of the disorders have been the object of NS. The most frequently cited reasons for the limitation are low prevalence and the lack of treatment. The tandem mass spectrometry has come in place in recent years across the globe, expanding NS to include several disorders of intermediary metabolism. This has shown, in addition to a prevalence much higher than previously thought, the benefits of early detection. The present work is a review of NS, not only from the point of view of technological/medical achievements, but also considering other factors which will affect specific disease selection, according to the social and organizational infrastructure that may expand the borders of NS. PMID:12921292

  10. MRSA Screening

    Science.gov (United States)

    ... limited. Home Visit Global Sites Search Help? MRSA Screening Share this page: Was this page helpful? Formal name: Methicillin resistant Staphylococcus aureus Screening Related tests: Wound Culture At a Glance Test ...

  11. A Rapid Screening Analysis of Antioxidant Compounds in Native Australian Food Plants Using Multiplexed Detection with Active Flow Technology Columns.

    Science.gov (United States)

    Rupesinghe, Emmanuel Janaka Rochana; Jones, Andrew; Shalliker, Ross Andrew; Pravadali-Cekic, Sercan

    2016-01-01

    Conventional techniques for identifying antioxidant and phenolic compounds in native Australian food plants are laborious and time-consuming. Here, we present a multiplexed detection technique that reduces analysis time without compromising separation performance. This technique is achieved using Active Flow Technology-Parallel Segmented Flow (AFT-PSF) columns. Extracts from cinnamon myrtle (Backhousia myrtifolia) and lemon myrtle (Backhousia citriodora) leaves were analysed via multiplexed detection using an AFT-PSF column with underivatised UV-VIS, mass spectroscopy (MS), and the 2,2-diphenyl-1-picrylhydrazyl (DPPH(•)) derivatisation for antioxidants as detection methods. A number of antioxidant compounds were detected in the extracts of each leaf extract. PMID:26805792

  12. Cancer screening

    OpenAIRE

    Krishna Prasad

    1987-01-01

    Cancer screening is a means to detect cancer early with the goal of decreasing morbidity and mortality. At present, there is a reasonable consensus regarding screening for breast, cervical and colorectal cances and the role of screening is under trial in case of cancers of the lung,  ovaries and prostate. On the other hand, good screening tests are not available for some of the commonest cancers in India like the oral, pharyngeal, esophageal and stomach cancers.

  13. Quantum Amplitude Amplification and Estimation

    CERN Document Server

    Brassard, G; Mosca, M; Tapp, A; Brassard, Gilles; Hoyer, Peter; Mosca, Michele; Tapp, Alain

    2000-01-01

    Consider a Boolean function $\\chi: X \\to \\{0,1\\}$ that partitions set $X$ between its good and bad elements, where $x$ is good if $\\chi(x)=1$ and bad otherwise. Consider also a quantum algorithm $\\mathcal A$ such that $A \\ket{0} = \\sum_{x\\in X} \\alpha_x \\ket{x}$ is a quantum superposition of the elements of $X$, and let $a$ denote the probability that a good element is produced if $A \\ket{0}$ is measured. If we repeat the process of running $A$, measuring the output, and using $\\chi$ to check the validity of the result, we shall expect to repeat $1/a$ times on the average before a solution is found. *Amplitude amplification* is a process that allows to find a good $x$ after an expected number of applications of $A$ and its inverse which is proportional to $1/\\sqrt{a}$, assuming algorithm $A$ makes no measurements. This is a generalization of Grover's searching algorithm in which $A$ was restricted to producing an equal superposition of all members of $X$ and we had a promise that a single $x$ existed such tha...

  14. Isothermal DNA amplification in vitro: the helicase-dependent amplification system.

    Science.gov (United States)

    Jeong, Yong-Joo; Park, Kkothanahreum; Kim, Dong-Eun

    2009-10-01

    Since the development of polymerase chain reaction, amplification of nucleic acids has emerged as an elemental tool for molecular biology, genomics, and biotechnology. Amplification methods often use temperature cycling to exponentially amplify nucleic acids; however, isothermal amplification methods have also been developed, which do not require heating the double-stranded nucleic acid to dissociate the synthesized products from templates. Among the several methods used for isothermal DNA amplification, the helicase-dependent amplification (HDA) is discussed in this review with an emphasis on the reconstituted DNA replication system. Since DNA helicase can unwind the double-stranded DNA without the need for heating, the HDA system provides a very useful tool to amplify DNA in vitro under isothermal conditions with a simplified reaction scheme. This review describes components and detailed aspects of current HDA systems using Escherichia coli UvrD helicase and T7 bacteriophage gp4 helicase with consideration of the processivity and efficiency of DNA amplification. PMID:19629390

  15. Process evaluation of a technology-delivered screening and brief intervention for substance use in primary care

    Directory of Open Access Journals (Sweden)

    Steven J. Ondersma

    2016-05-01

    Full Text Available Psychotherapy process research examines the content of treatment sessions and their association with outcomes in an attempt to better understand the interactions between therapists and clients, and to elucidate mechanisms of behavior change. A similar approach is possible in technology-delivered interventions, which have an interaction process that is always perfectly preserved and rigorously definable. The present study sought to examine the process of participants' interactions with a computer-delivered brief intervention for drug use, from a study comparing computer- and therapist-delivered brief interventions among adults at two primary health care centers in New Mexico. Specifically, we sought to describe the pattern of participants' (N = 178 choices and reactions throughout the computer-delivered brief intervention, and to examine associations between that process and intervention response at 3-month follow-up. Participants were most likely to choose marijuana as the first substance they wished to discuss (n = 114, 64.0%. Most participants indicated that they had not experienced any problems as a result of their drug use (n = 108, 60.7%, but nearly a third of these (n = 32, 29.6% nevertheless indicated a desire to stop or reduce its use; participants who did report negative consequences were most likely to endorse financial or relationship concerns. However, participant ratings of the importance of change or of the helpfulness of personalized normed feedback were unrelated to changes in substance use frequency. Design of future e-interventions should consider emphasizing possible benefits of quitting rather than the negative consequences of drug use, and—when addressing consequences—should consider focusing on the impacts of substance use on relationship and financial aspects. These findings are an early but important step toward using process evaluation to optimize e-intervention content.

  16. Whole genome amplification of DNA for genotyping pharmacogenetics candidate genes.

    Directory of Open Access Journals (Sweden)

    Santosh ePhilips

    2012-03-01

    Full Text Available Whole genome amplification (WGA technologies can be used to amplify genomic DNA when only small amounts of DNA are available. The Multiple Displacement Amplification Phi polymerase based amplification has been shown to accurately amplify DNA for a variety of genotyping assays; however, it has not been tested for genotyping many of the clinically relevant genes important for pharmacogenetic studies, such as the cytochrome P450 genes, that are typically difficult to genotype due to multiple pseudogenes, copy number variations, and high similarity to other related genes. We evaluated whole genome amplified samples for Taqman™ genotyping of SNPs in a variety of pharmacogenetic genes. In 24 DNA samples from the Coriell human diversity panel, the call rates and concordance between amplified (~200-fold amplification and unamplified samples was 100% for two SNPs in CYP2D6 and one in ESR1. In samples from a breast cancer clinical trial (Trial 1, we compared the genotyping results in samples before and after WGA for four SNPs in CYP2D6, one SNP in CYP2C19, one SNP in CYP19A1, two SNPs in ESR1, and two SNPs in ESR2. The concordance rates were all >97%. Finally, we compared the allele frequencies of 143 SNPs determined in Trial 1 (whole genome amplified DNA to the allele frequencies determined in unamplified DNA samples from a separate trial (Trial 2 that enrolled a similar population. The call rates and allele frequencies between the two trials were 98% and 99.7%, respectively. We conclude that the whole genome amplified DNA is suitable for Taqman™ genotyping for a wide variety of pharmacogenetically relevant SNPs.

  17. Can Anomalous Amplification be Attained without Postselection?

    Science.gov (United States)

    Martínez-Rincón, Julián; Liu, Wei-Tao; Viza, Gerardo I.; Howell, John C.

    2016-03-01

    We present a parameter estimation technique based on performing joint measurements of a weak interaction away from the weak-value-amplification approximation. Two detectors are used to collect full statistics of the correlations between two weakly entangled degrees of freedom. Without discarding of data, the protocol resembles the anomalous amplification of an imaginary-weak-value-like response. The amplification is induced in the difference signal of both detectors allowing robustness to different sources of technical noise, and offering in addition the advantages of balanced signals for precision metrology. All of the Fisher information about the parameter of interest is collected. A tunable phase controls the strength of the amplification response. We experimentally demonstrate the proposed technique by measuring polarization rotations in a linearly polarized laser pulse. We show that in the presence of technical noise the effective sensitivity and precision of a split detector is increased when compared to a conventional continuous-wave balanced detection technique.

  18. Privacy amplification for quantum key distribution

    International Nuclear Information System (INIS)

    This paper examines classical privacy amplification using a universal family of hash functions. In quantum key distribution, the adversary's measurement can wait until the choice of hash functions is announced, and so the adversary's information may depend on the choice. Therefore the existing result on classical privacy amplification, which assumes the independence of the choice from the other random variables, is not applicable to this case. This paper provides a security proof of privacy amplification which is valid even when the adversary's information may depend on the choice of hash functions. The compression rate of the proposed privacy amplification can be taken to be the same as that of the existing one with an exponentially small loss in secrecy of a final key. (fast track communication)

  19. Loop-mediated isothermal amplification technology in the rapid detection of Bacillus anthracis%环介导等温扩增技术在快速检测炭疽芽胞杆菌中的应用

    Institute of Scientific and Technical Information of China (English)

    段圣亮; 陆晔; 田桢干; 王桂江

    2012-01-01

    The present paper aims to establish a rapid detection method for Bacillus anthracis. The primes were designed according to Bacillus anthracis strain-specific gene fragment, and loop-mediated isothermal amplification (LAMP) was used to establish the detection method . The results showed that LAMP can effectively identify the specific target bacteria with sensitivity of 102 -103 CFU/ml. It is suggested that LAMP is simple and fast in detection of bioterrorism bacteria such as Bacillus anthracis in acidic , alkaline and viscous media. High-salt environment influences LAMP results , so it is necessary to effectively remove salt out of nucleic acid before application of LAMP .%本文旨在建立适合国境口岸现场应用的生物恐怖防控快速检测方法,从而保障口岸安全.针对生物恐怖炭疽芽胞杆菌,选择目标菌种特异性基因片段,设计引物,运用环介导等温扩增(LAMP)技术建立一套简便、高效的检测方法,并模拟生物恐怖炭疽芽胞杆菌可能存在的基质条件,评价LAMP技术在快速筛查中的适用性.结果显示,LAMP技术排查生物恐怖炭疽芽胞杆菌简便、快速、特异,检测灵敏度为102~103 CFU/ml;且能有效检出在偏酸、偏碱及黏稠基质中的炭疽芽胞杆菌.而高盐环境对该反应影响较大,有必要采用能有效去除盐分的核酸抽提方法.

  20. Recombinase Polymerase Amplification (RPA) of CaMV-35S Promoter and nos Terminator for Rapid Detection of Genetically Modified Crops

    OpenAIRE

    Chao Xu; Liang Li; Wujun Jin; Yusong Wan

    2014-01-01

    Recombinase polymerase amplification (RPA) is a novel isothermal DNA amplification and detection technology that enables the amplification of DNA within 30 min at a constant temperature of 37–42 °C by simulating in vivo DNA recombination. In this study, based on the regulatory sequence of the cauliflower mosaic virus 35S (CaMV-35S) promoter and the Agrobacterium tumefaciens nopaline synthase gene (nos) terminator, which are widely incorporated in genetically modified (GM) crops, we designed t...

  1. Rolling circle amplification of metazoan mitochondrialgenomes

    Energy Technology Data Exchange (ETDEWEB)

    Simison, W. Brian; Lindberg, D.R.; Boore, J.L.

    2005-07-31

    Here we report the successful use of rolling circle amplification (RCA) for the amplification of complete metazoan mt genomes to make a product that is amenable to high-throughput genome sequencing techniques. The benefits of RCA over PCR are many and with further development and refinement of RCA, the sequencing of organellar genomics will require far less time and effort than current long PCR approaches.

  2. The Development Situation of Screening Technology for Biomass Pellet Fuel%农林生物质原料筛分技术与设备发展现状

    Institute of Scientific and Technical Information of China (English)

    张妍; 赵立欣; 郭占斌; 杨宏志; 孟海波; 姚宗路

    2015-01-01

    针对目前生物质原料中杂质多、筛分设备不匹配等问题,对各类生物质原料进行分类,总结国内外筛分技术的发展现状。同时,通过对杂质的特性分析,针对目前的筛分方法、筛分机械进行相对应的应用,旨在提出一种适合我国生物质成型燃料大规模生产的筛分技术及配套设备,为生物质原料清选工艺提供技术支撑。%For the current biomass feedstock has many impurities , screening equipment does not match the supply of bio-mass feedstock and the other issues , this thesis classifies various types of biomass feedstock , summarizes screening tech-nology development at home and abroad .And through the analysis of the characteristics of impurities , for the current screening methods and screening machinery , the thesis is expected to propose a screening technology and equipment suit-able for Chinese large-scale production of biomass briquettes , to provide technical support for cleaning process .

  3. Detection of the 35S promoter in transgenic maize via various isothermal amplification techniques: a practical approach.

    Science.gov (United States)

    Zahradnik, Celine; Kolm, Claudia; Martzy, Roland; Mach, Robert L; Krska, Rudolf; Farnleitner, Andreas H; Brunner, Kurt

    2014-11-01

    In 2003 the European Commission introduced a 0.9% threshold for food and feed products containing genetically modified organism (GMO)-derived components. For commodities containing GMO contents higher than this threshold, labelling is mandatory. To provide a DNA-based rapid and simple detection method suitable for high-throughput screening of GMOs, several isothermal amplification approaches for the 35S promoter were tested: strand displacement amplification, nicking-enzyme amplification reaction, rolling circle amplification, loop-mediated isothermal amplification (LAMP) and helicase-dependent amplification (HDA). The assays developed were tested for specificity in order to distinguish between samples containing genetically modified (GM) maize and non-GM maize. For those assays capable of this discrimination, tests were performed to determine the lower limit of detection. A false-negative rate was determined to rule out whether GMO-positive samples were incorrectly classified as GMO-negative. A robustness test was performed to show reliable detection independent from the instrument used for amplification. The analysis of three GM maize lines showed that only LAMP and HDA were able to differentiate between the GMOs MON810, NK603, and Bt11 and non-GM maize. Furthermore, with the HDA assay it was possible to realize a detection limit as low as 0.5%. A false-negative rate of only 5% for 1% GM maize for all three maize lines shows that HDA has the potential to be used as an alternative strategy for the detection of transgenic maize. All results obtained with the LAMP and HDA assays were compared with the results obtained with a previously reported real-time PCR assay for the 35S promoter in transgenic maize. This study presents two new screening assays for detection of the 35S promoter in transgenic maize by applying the isothermal amplification approaches HDA and LAMP. PMID:24880871

  4. Onshore seismic amplifications due to bathymetric features

    Science.gov (United States)

    Rodríguez-Castellanos, A.; Carbajal-Romero, M.; Flores-Guzmán, N.; Olivera-Villaseñor, E.; Kryvko, A.

    2016-08-01

    We perform numerical calculations for onshore seismic amplifications, taking into consideration the effect of bathymetric features on the propagation of seismic movements. To this end, the boundary element method is applied. Boundary elements are employed to irradiate waves and, consequently, force densities can be obtained for each boundary element. From this assumption, Huygens’ principle is applied, and since the diffracted waves are built at the boundary from which they are radiated, this idea is equivalent to Somigliana’s representation theorem. The application of boundary conditions leads to a linear system being obtained (Fredholm integral equations). Several numerical models are analyzed, with the first one being used to verify the proposed formulation, and the others being used to estimate onshore seismic amplifications due to the presence of bathymetric features. The results obtained show that compressional waves (P-waves) generate onshore seismic amplifications that can vary from 1.2 to 5.2 times the amplitude of the incident wave. On the other hand, the shear waves (S-waves) can cause seismic amplifications of up to 4.0 times the incident wave. Furthermore, an important result is that in most cases the highest seismic amplifications from an offshore earthquake are located on the shoreline and not offshore, despite the seafloor configuration. Moreover, the influence of the incident angle of seismic waves on the seismic amplifications is highlighted.

  5. Amplification uncertainty relation for probabilistic amplifiers

    Science.gov (United States)

    Namiki, Ryo

    2015-09-01

    Traditionally, quantum amplification limit refers to the property of inevitable noise addition on canonical variables when the field amplitude of an unknown state is linearly transformed through a quantum channel. Recent theoretical studies have determined amplification limits for cases of probabilistic quantum channels or general quantum operations by specifying a set of input states or a state ensemble. However, it remains open how much excess noise on canonical variables is unavoidable and whether there exists a fundamental trade-off relation between the canonical pair in a general amplification process. In this paper we present an uncertainty-product form of amplification limits for general quantum operations by assuming an input ensemble of Gaussian-distributed coherent states. It can be derived as a straightforward consequence of canonical uncertainty relations and retrieves basic properties of the traditional amplification limit. In addition, our amplification limit turns out to give a physical limitation on probabilistic reduction of an Einstein-Podolsky-Rosen uncertainty. In this regard, we find a condition that probabilistic amplifiers can be regarded as local filtering operations to distill entanglement. This condition establishes a clear benchmark to verify an advantage of non-Gaussian operations beyond Gaussian operations with a feasible input set of coherent states and standard homodyne measurements.

  6. Identification of human chromosome 9 specific genes using exon amplification.

    Science.gov (United States)

    Church, D M; Banks, L T; Rogers, A C; Graw, S L; Housman, D E; Gusella, J F; Buckler, A J

    1993-11-01

    We have recently developed a method, exon amplification, that is designed for isolation of exon sequences from genomic DNA. To assess the efficacy of this method we have analyzed cosmid genomic clones derived from human chromosome 9, and have cloned several products from this analysis. Approximately 63% of cosmids produced at least one product derived from functioning splice sites within the target genomic fragment, and in many cases multiple products were isolated. In addition, an easily identifiable class of false positives was produced from 56% of cosmids analyzed; these are readily eliminated from subsequent study. Sequence analysis and database searches revealed that the majority (87%) of the putative exon clones were unique, the remainder being derived from repetitive sequences. Analysis of sequence conservation by Southern blotting in addition to cDNA screening experiments suggested that most, if not all, of these unique sequences represent true exons. The results of these studies indicate that exon amplification is a rapid and reliable approach for isolation of exon sequences from mammalian genomic DNA. PMID:7506603

  7. Detection of specific DNA sequences by fluorescence amplification: a color complementation assay.

    OpenAIRE

    Chehab, F. F.; Kan, Y W

    1989-01-01

    We have developed a color complementation assay that allows rapid screening of specific genomic DNA sequences. It is based on the simultaneous amplification of two or more DNA segments with fluorescent oligonucleotide primers such that the generation of a color, or combination of colors, can be visualized and used for diagnosis. Color complementation assay obviates the need for gel electrophoresis and has been applied to the detection of a large and small gene deletion, a chromosomal transloc...

  8. The detection of Plasmodiophora brassicae using loop-mediated isothermal DNA amplification

    OpenAIRE

    Joanna Kaczmarek; Witold Irzykowski; Adam Burzyński; Małgorzata Jędryczka

    2014-01-01

    Plasmodiophora brassicae, the cause of clubroot, is a very serious problem preventing from successful and profitable cultivation of oilseed rape in Poland. The pathogen was found in all main growing areas of oilseed rape; it also causes considerable problems in growing of vegetable brassicas. The aim of this work was to elaborate fast, cheap and reliable screening method to detect P. brassicae. To achieve this aim the Loop-mediated isothermal DNA amplification (LAMP) technique has been elabor...

  9. Heat induces gene amplification in cancer cells

    International Nuclear Information System (INIS)

    Highlights: ► This study discovered that heat exposure (hyperthermia) results in gene amplification in cancer cells. ► Hyperthermia induces DNA double strand breaks. ► DNA double strand breaks are considered to be required for the initiation of gene amplification. ► The underlying mechanism of heat-induced gene amplification is generation of DNA double strand breaks. -- Abstract: Background: Hyperthermia plays an important role in cancer therapy. However, as with radiation, it can cause DNA damage and therefore genetic instability. We studied whether hyperthermia can induce gene amplification in cancer cells and explored potential underlying molecular mechanisms. Materials and methods: (1) Hyperthermia: HCT116 colon cancer cells received water-submerged heating treatment at 42 or 44 °C for 30 min; (2) gene amplification assay using N-(phosphoacetyl)-L-aspartate (PALA) selection of cabamyl-P-synthetase, aspartate transcarbarmylase, dihydro-orotase (cad) gene amplified cells; (3) southern blotting for confirmation of increased cad gene copies in PALA-resistant cells; (4) γH2AX immunostaining to detect γH2AX foci as an indication for DNA double strand breaks. Results: (1) Heat exposure at 42 or 44 °C for 30 min induces gene amplification. The frequency of cad gene amplification increased by 2.8 and 6.5 folds respectively; (2) heat exposure at both 42 and 44 °C for 30 min induces DNA double strand breaks in HCT116 cells as shown by γH2AX immunostaining. Conclusion: This study shows that heat exposure can induce gene amplification in cancer cells, likely through the generation of DNA double strand breaks, which are believed to be required for the initiation of gene amplification. This process may be promoted by heat when cellular proteins that are responsible for checkpoints, DNA replication, DNA repair and telomere functions are denatured. To our knowledge, this is the first study to provide direct evidence of hyperthermia induced gene amplification.

  10. Heat induces gene amplification in cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Bin, E-mail: yanbin@mercyhealth.com [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS 39213 (United States); Mercy Cancer Center, Mercy Medical Center-North Iowa, Mason City, IA 50401 (United States); Ouyang, Ruoyun [Department of Respiratory Medicine, The Second Xiangya Hospital, Xinagya School of Medicine, Central South University, Changsha 410011 (China); Huang, Chenghui [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS 39213 (United States); Department of Oncology, The Third Xiangya Hospital, Xinagya School of Medicine, Central South University, Changsha 410013 (China); Liu, Franklin [Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710 (United States); Neill, Daniel [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS 39213 (United States); Li, Chuanyuan [Dermatology, Duke University Medical Center, Durham, NC 27710 (United States); Dewhirst, Mark [Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710 (United States)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer This study discovered that heat exposure (hyperthermia) results in gene amplification in cancer cells. Black-Right-Pointing-Pointer Hyperthermia induces DNA double strand breaks. Black-Right-Pointing-Pointer DNA double strand breaks are considered to be required for the initiation of gene amplification. Black-Right-Pointing-Pointer The underlying mechanism of heat-induced gene amplification is generation of DNA double strand breaks. -- Abstract: Background: Hyperthermia plays an important role in cancer therapy. However, as with radiation, it can cause DNA damage and therefore genetic instability. We studied whether hyperthermia can induce gene amplification in cancer cells and explored potential underlying molecular mechanisms. Materials and methods: (1) Hyperthermia: HCT116 colon cancer cells received water-submerged heating treatment at 42 or 44 Degree-Sign C for 30 min; (2) gene amplification assay using N-(phosphoacetyl)-L-aspartate (PALA) selection of cabamyl-P-synthetase, aspartate transcarbarmylase, dihydro-orotase (cad) gene amplified cells; (3) southern blotting for confirmation of increased cad gene copies in PALA-resistant cells; (4) {gamma}H2AX immunostaining to detect {gamma}H2AX foci as an indication for DNA double strand breaks. Results: (1) Heat exposure at 42 or 44 Degree-Sign C for 30 min induces gene amplification. The frequency of cad gene amplification increased by 2.8 and 6.5 folds respectively; (2) heat exposure at both 42 and 44 Degree-Sign C for 30 min induces DNA double strand breaks in HCT116 cells as shown by {gamma}H2AX immunostaining. Conclusion: This study shows that heat exposure can induce gene amplification in cancer cells, likely through the generation of DNA double strand breaks, which are believed to be required for the initiation of gene amplification. This process may be promoted by heat when cellular proteins that are responsible for checkpoints, DNA replication, DNA repair and

  11. AMPLIFICATION OF RIBOSOMAL RNA SEQUENCES

    Science.gov (United States)

    This book chapter offers an overview of the use of ribosomal RNA sequences. A history of the technology traces the evolution of techniques to measure bacterial phylogenetic relationships and recent advances in obtaining rRNA sequence information. The manual also describes procedu...

  12. Generalizing Screen Inferiority--Does the Medium, Screen versus Paper, Affect Performance Even with Brief Tasks?

    Science.gov (United States)

    Sidi, Yael; Ophir, Yael; Ackerman, Rakefet

    2016-01-01

    Screen inferiority in performance and metacognitive processes has been repeatedly found with text learning. Common explanations for screen inferiority relate to technological and physiological disadvantages associated with extensive reading on screen. However, recent studies point to lesser recruitment of mental effort on screen than on paper.…

  13. Post-Fragmentation Whole Genome Amplification-Based Method

    Science.gov (United States)

    Benardini, James; LaDuc, Myron T.; Langmore, John

    2011-01-01

    This innovation is derived from a proprietary amplification scheme that is based upon random fragmentation of the genome into a series of short, overlapping templates. The resulting shorter DNA strands (DNA fragments with defined 3 and 5 termini. Specific primers to these termini are then used to isothermally amplify this library into potentially unlimited quantities that can be used immediately for multiple downstream applications including gel eletrophoresis, quantitative polymerase chain reaction (QPCR), comparative genomic hybridization microarray, SNP analysis, and sequencing. The standard reaction can be performed with minimal hands-on time, and can produce amplified DNA in as little as three hours. Post-fragmentation whole genome amplification-based technology provides a robust and accurate method of amplifying femtogram levels of starting material into microgram yields with no detectable allele bias. The amplified DNA also facilitates the preservation of samples (spacecraft samples) by amplifying scarce amounts of template DNA into microgram concentrations in just a few hours. Based on further optimization of this technology, this could be a feasible technology to use in sample preservation for potential future sample return missions. The research and technology development described here can be pivotal in dealing with backward/forward biological contamination from planetary missions. Such efforts rely heavily on an increasing understanding of the burden and diversity of microorganisms present on spacecraft surfaces throughout assembly and testing. The development and implementation of these technologies could significantly improve the comprehensiveness and resolving power of spacecraft-associated microbial population censuses, and are important to the continued evolution and advancement of planetary protection capabilities. Current molecular procedures for assaying spacecraft-associated microbial burden and diversity have inherent sample loss issues at

  14. Environmental Whole-Genome Amplification to Access Microbial Diversity in Contaminated Sediments

    Energy Technology Data Exchange (ETDEWEB)

    Abulencia, C.B.; Wyborski, D.L.; Garcia, J.; Podar, M.; Chen, W.; Chang, S.H.; Chang, H.W.; Watson, D.; Brodie,E.I.; Hazen, T.C.; Keller, M.

    2005-12-10

    Low-biomass samples from nitrate and heavy metal contaminated soils yield DNA amounts that have limited use for direct, native analysis and screening. Multiple displacement amplification (MDA) using ?29 DNA polymerase was used to amplify whole genomes from environmental, contaminated, subsurface sediments. By first amplifying the genomic DNA (gDNA), biodiversity analysis and gDNA library construction of microbes found in contaminated soils were made possible. The MDA method was validated by analyzing amplified genome coverage from approximately five Escherichia coli cells, resulting in 99.2 percent genome coverage. The method was further validated by confirming overall representative species coverage and also an amplification bias when amplifying from a mix of eight known bacterial strains. We extracted DNA from samples with extremely low cell densities from a U.S. Department of Energy contaminated site. After amplification, small subunit rRNA analysis revealed relatively even distribution of species across several major phyla. Clone libraries were constructed from the amplified gDNA, and a small subset of clones was used for shotgun sequencing. BLAST analysis of the library clone sequences showed that 64.9 percent of the sequences had significant similarities to known proteins, and ''clusters of orthologous groups'' (COG) analysis revealed that more than half of the sequences from each library contained sequence similarity to known proteins. The libraries can be readily screened for native genes or any target of interest. Whole-genome amplification of metagenomic DNA from very minute microbial sources, while introducing an amplification bias, will allow access to genomic information that was not previously accessible.

  15. Advanced unrepeatered systems using novel Raman amplification schemes

    Science.gov (United States)

    Chang, Do-il; Pelouch, Wayne; Burtsev, Sergey; Perrier, Philippe; Fevrier, Herve

    2015-01-01

    Unrepeatered transmission systems provide a cost-effective solution to transmit high capacity channels in submarine networks to communicate between coastal population centers or in terrestrial networks to connect remote areas where service access is difficult. The main goal of unrepeatered systems has traditionally been to achieve the longest reach, however, increasing traffic demands now require unrepeatered systems to support both longer reach and higher transport capacity. As a result, transmission rate of unrepeatered systems has quickly moved from 10 Gb/s to 40 Gb/s or 100 Gb/s. This paper reviews the key basic technologies, with a specific focus on Raman amplification, required for long-reach, high-capacity unrepeatered optical transmission systems. We will discuss novel Raman amplification schemes, enhanced remote optically pumped amplifiers (ROPA), ultra-low loss / large effective area fibers, and coherent transmission with advanced modulation format and high FEC coding gain. We will also report recent experimental demonstrations that show how these technologies have been combined to achieve industry's leading capacity and reach transmission.

  16. Sensitive SERS detection of miRNA via enzyme-free DNA machine signal amplification.

    Science.gov (United States)

    Li, Xiaoxiao; Ye, Sujuan; Luo, Xiliang

    2016-08-11

    In this work, an enzyme-free signal amplified detection platform is described for miRNA detection with a DNA fueled molecular machine. Coupling SERS technology with multiple amplification modes, this flexible biosensing system exhibits high sensitivity and specificity. PMID:27469084

  17. Impact of human genome initiative-derived technology on genetic testing, screening and counseling: Cultural, ethical and legal issues. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Trottier, R.W.; Hodgin, F.C.; Imara, M.; Phoenix, D.; Lybrook, S. [Morehouse Coll., Atlanta, GA (United States). School of Medicine; Crandall, L.A.; Moseley, R.E.; Armotrading, D. [Florida Univ., Gainesville, FL (United States). Coll. of Medicine

    1993-03-01

    Genetic medical services provided by the Georgia Division of Public Health in two northern and two central districts are compared to services provided in a district in which a tertiary care facility is located. Genetics outreach public health nurses play key roles in Georgia`s system of Children`s Health Services Genetics Program, including significant roles as counselors and information sources on special needs social services and support organizations. Unique features of individual health districts, (e.g., the changing face of some rural communities in ethnocultural diversity and socioeconomic character), present new challenges to current and future genetics services delivery. Preparedness as to educational needs of both health professionals and the lay population is of foremost concern in light of the ever expanding knowledge and technology in medical genetics. Perspectives on genetics and an overview of services offered by a local private sector counselor are included for comparison to state supported services. The nature of the interactions which transpire between private and public genetic services resources in Georgia will be described. A special focus of this research includes issues associated with sickle cell disease newborn screening service delivery process in Georgia, with particular attention paid to patient follow-up and transition to primary care. Of particular interest to this focus is the problem of loss to follow-up in the current system. Critical factors in education and counseling of sickle cell patients and the expectations of expanding roles of primary care physicians are discussed. The Florida approach to the delivery of genetic services contrasts to the Georgia model by placing more emphasis on a consultant-specialist team approach.

  18. ESTIMATION OF AMPLIFICATION FACTOR IN EARTHQUAKE ENGINEERING

    Directory of Open Access Journals (Sweden)

    Nazarov Yuriy Pavlovich

    2015-03-01

    Full Text Available The authors are the developers of Odyssey Software (Eurosoft Co. for the analysis of seismological data and computing of seismic loads and their parameters. While communicating with the users of the software, the authors have revealed some uncertainty about both understanding of the term "amplification factor (AF" and calculation of the amplification factor using various methods. In this article, a simple example shows that the determination of the amplification factor as the ratio of the acceleration’s spectrum to the maximal acceleration is derived from the classical definition of AF in the form of the ratio of maximal dynamic displacement to the displacement by the action of static load. Deterministic and probabilistic ap-proaches for the calculating of the AF were discussed. There was an example of AFs calculation and their envelopes for translational and rotational components of seismic impact by using Odyssey Software.

  19. On Arbitrary Phases in Quantum Amplitude Amplification

    CERN Document Server

    Hoyer, P

    2000-01-01

    We consider the use of arbitrary phases in quantum amplitude amplification which is a generalization of quantum searching. We prove that the phase condition in amplitude amplification is given by $\\tan(\\phi/2)=\\tan(\\phi/2)(1-2a)$, where $\\phi$ and $\\phi$ are the phases used and where $a$ is the success probability of the given algorithm. Thus the choice of phases depends nontrivially and nonlinearly on the success probability. Utilizing this condition, we give methods for constructing quantum algorithms that succeed with certainty and for implementing arbitrary rotations. We also conclude that phase errors of order up to $\\frac{1}{\\sqrt{a}}$ can be tolerated in amplitude amplification.

  20. Breast Cancer Screening

    Science.gov (United States)

    ... of Breast & Gynecologic Cancers Breast Cancer Screening Research Breast Cancer Screening (PDQ®)–Patient Version What is screening? Screening ... cancer screening: Cancer Screening Overview General Information About Breast Cancer Key Points Breast cancer is a disease in ...

  1. Rapid detection of Mycobacterium tuberculosis by recombinase polymerase amplification.

    Directory of Open Access Journals (Sweden)

    David S Boyle

    Full Text Available Improved access to effective tests for diagnosing tuberculosis (TB has been designated a public health priority by the World Health Organisation. In high burden TB countries nucleic acid based TB tests have been restricted to centralised laboratories and specialised research settings. Requirements such as a constant electrical supply, air conditioning and skilled, computer literate operators prevent implementation of such tests in many settings. Isothermal DNA amplification technologies permit the use of simpler, less energy intensive detection platforms more suited to low resource settings that allow the accurate diagnosis of a disease within a short timeframe. Recombinase Polymerase Amplification (RPA is a rapid, low temperature isothermal DNA amplification reaction. We report here RPA-based detection of Mycobacterium tuberculosis complex (MTC DNA in <20 minutes at 39 °C. Assays for two MTC specific targets were investigated, IS6110 and IS1081. When testing purified MTC genomic DNA, limits of detection of 6.25 fg (IS6110 and 20 fg (IS1081were consistently achieved. When testing a convenience sample of pulmonary specimens from suspected TB patients, RPA demonstrated superior accuracy to indirect fluorescence microscopy. Compared to culture, sensitivities for the IS1081 RPA and microscopy were 91.4% (95%CI: 85, 97.9 and 86.1% (95%CI: 78.1, 94.1 respectively (n = 71. Specificities were 100% and 88.6% (95% CI: 80.8, 96.1 respectively. For the IS6110 RPA and microscopy sensitivities of 87.5% (95%CI: 81.7, 93.2 and 70.8% (95%CI: 62.9, 78.7 were obtained (n = 90. Specificities were 95.4 (95% CI: 92.3,98.1 and 88% (95% CI: 83.6, 92.4 respectively. The superior specificity of RPA for detecting tuberculosis was due to the reduced ability of fluorescence microscopy to distinguish Mtb complex from other acid fast bacteria. The rapid nature of the RPA assay and its low energy requirement compared to other amplification technologies suggest RPA-based TB

  2. The Future of Prenatal Diagnosis and Screening

    OpenAIRE

    Eugene Pergament

    2014-01-01

    The future of prenatal diagnosis and screening lies in developing clinical approaches and laboratory technologies applicable to genetic analyses and therapeutic interventions during embryonic development.

  3. Screening for Panic Disorder

    Science.gov (United States)

    ... Conference & Education Membership Journal & Multimedia Resources Awards Consumers Screening for Panic Disorder Main navigation FAQs Screen Yourself Screening for Depression Screening for Generalized Anxiety Disorder (GAD) ...

  4. Two Methods of Whole-Genome Amplification Enable Accurate Genotyping Across a 2320-SNP Linkage Panel

    OpenAIRE

    Barker, David L.; Hansen, Mark S. T.; Faruqi, A. Fawad; Giannola, Diane; Irsula, Orlando R.; Lasken, Roger S; Latterich, Martin; Makarov, Vladimir; Oliphant, Arnold; Pinter, Jonathon H.; Shen, Richard; Sleptsova, Irina; Ziehler, William; Lai, Eric

    2004-01-01

    Comprehensive genome scans involving many thousands of SNP assays will require significant amounts of genomic DNA from each sample. We report two successful methods for amplifying whole-genomic DNA prior to SNP analysis, multiple displacement amplification, and OmniPlex technology. We determined the coverage of amplification by analyzing a SNP linkage marker set that contained 2320 SNP markers spread across the genome at an average distance of 2.5 cM. We observed a concordance of >99.8% in ge...

  5. Novel bioluminescent quantitative detection of nucleic acid amplification in real-time.

    Directory of Open Access Journals (Sweden)

    Olga A Gandelman

    Full Text Available BACKGROUND: The real-time monitoring of polynucleotide amplification is at the core of most molecular assays. This conventionally relies on fluorescent detection of the amplicon produced, requiring complex and costly hardware, often restricting it to specialised laboratories. PRINCIPAL FINDINGS: Here we report the first real-time, closed-tube luminescent reporter system for nucleic acid amplification technologies (NAATs enabling the progress of amplification to be continuously monitored using simple light measuring equipment. The Bioluminescent Assay in Real-Time (BART continuously reports through bioluminescent output the exponential increase of inorganic pyrophosphate (PPi produced during the isothermal amplification of a specific nucleic acid target. BART relies on the coupled conversion of inorganic pyrophosphate (PPi produced stoichiometrically during nucleic acid synthesis to ATP by the enzyme ATP sulfurylase, and can therefore be coupled to a wide range of isothermal NAATs. During nucleic acid amplification, enzymatic conversion of PPi released during DNA synthesis into ATP is continuously monitored through the bioluminescence generated by thermostable firefly luciferase. The assay shows a unique kinetic signature for nucleic acid amplifications with a readily identifiable light output peak, whose timing is proportional to the concentration of original target nucleic acid. This allows qualitative and quantitative analysis of specific targets, and readily differentiates between negative and positive samples. Since quantitation in BART is based on determination of time-to-peak rather than absolute intensity of light emission, complex or highly sensitive light detectors are not required. CONCLUSIONS: The combined chemistries of the BART reporter and amplification require only a constant temperature maintained by a heating block and are shown to be robust in the analysis of clinical samples. Since monitoring the BART reaction requires only a

  6. Hypertension screening

    Science.gov (United States)

    Foulke, J. M.

    1975-01-01

    An attempt was made to measure the response to an announcement of hypertension screening at the Goddard Space Center, to compare the results to those of previous statistics. Education and patient awareness of the problem were stressed.

  7. Airport Screening

    Science.gov (United States)

    ... ionizing radiation for security screening individuals [online]. Health Physics Society Position Statement. 2009. Available at http: / / hps. org/ documents/ securityscreening_ ps017- 1. pdf. Accessed 7 January 2011. Interagency Steering Committee on ...

  8. The effect of a 'vanishing twin' on biochemical and ultrasound first trimester screening markers for Down's syndrome in pregnancies conceived by assisted reproductive technology

    DEFF Research Database (Denmark)

    Gjerris, A C; Loft, A; Pinborg, Anja; Christiansen, M; Tabor, A

    2008-01-01

    BACKGROUND: Previous studies have found that 1 in 10 in vitro fertilization (IVF) singletons originates from a twin gestation. First trimester Down's syndrome screening markers are altered in assisted reproductive techniques (ART) pregnancies compared with spontaneously conceived pregnancies. The...

  9. Adult hearing screening: the Cyprus Pilot Program

    Directory of Open Access Journals (Sweden)

    C. Thodi

    2011-03-01

    Full Text Available Hearing loss is the third most common condition affecting adults over 65 (Cruickshanks et al., 1998. It can affect quality of life, limiting the ability to communicate efficiently, and leading to isolation, psychological strain, and functional decline (LaForge, Spector, Sternberg, 1992; Yueh, Shapiro, MacLean, Shekelle, 2003. Communication limitations impinge on the person directly, as well as the family, friends, and social circle. Reports on hearing loss among adults indicate that less than 25% of people who can benefit from amplification are actually using hearing aids, and that people diagnosed with a hearing loss delay seeking amplification by about seven years (Kochkin, 1997. Often, family members are the driving force behind a person with a hearing loss who decides to seek help. Adult hearing screening programs might have a positive effect on raising public awareness on hearing loss and its implications, and shortening delay time for intervention. There is no routine hearing screening for the adult population in Cyprus. The health system provides hearing tests for beneficiaries upon physician recommendation or self-referral. The Cyprus pilot adult hearing screening program (ΑΠΑΣ- EVERYONE- Greek acronym for Screening- Intervention-Hearing-Participation to Life screened hearing in retired adults.

  10. Thermostable Mismatch-Recognizing Protein MutS Suppresses Nonspecific Amplification during Polymerase Chain Reaction (PCR

    Directory of Open Access Journals (Sweden)

    Seiki Kuramitsu

    2013-03-01

    Full Text Available Polymerase chain reaction (PCR-related technologies are hampered mainly by two types of error: nonspecific amplification and DNA polymerase-generated mutations. Here, we report that both errors can be suppressed by the addition of a DNA mismatch-recognizing protein, MutS, from a thermophilic bacterium. Although it had been expected that MutS has a potential to suppress polymerase-generated mutations, we unexpectedly found that it also reduced nonspecific amplification. On the basis of this finding, we propose that MutS binds a mismatched primer-template complex, thereby preventing the approach of DNA polymerase to the 3' end of the primer. Our simple methodology improves the efficiency and accuracy of DNA amplification and should therefore benefit various PCR-based applications, ranging from basic biological research to applied medical science.

  11. Optical Pattern Recognition With Self-Amplification

    Science.gov (United States)

    Liu, Hua-Kuang

    1994-01-01

    In optical pattern recognition system with self-amplification, no reference beam used in addressing mode. Polarization of laser beam and orientation of photorefractive crystal chosen to maximize photorefractive effect. Intensity of recognition signal is orders of magnitude greater than other optical correlators. Apparatus regarded as real-time or quasi-real-time optical pattern recognizer with memory and reprogrammability.

  12. Social amplification of risk: a conceptual framework

    International Nuclear Information System (INIS)

    One of the most perplexing problems in risk analysis is why some relatively minor risks or risk events, as assessed by technical experts, often elicit strong public concerns and result in substantial impacts upon society and economy. This article sets forth a conceptual framework that seeks to link systematically the technical assessment of risk with psychological, sociological, and cultural perspectives of risk perception and risk-related behavior. The main thesis is that hazards interact with psychological, social, institutional, and cultural processes in ways that may amplify or attenuate public responses to the risk or risk event. A structural description of the social amplification of risk is now possible. Amplification occurs at two stages: in the transfer of information about the risk, and in the response mechanisms of society. Signals about risk are processed by individual and social amplification stations, including the scientist who communicates the risk assessment, the news media, cultural groups, interpersonal networks, and others. Key steps of amplifications can be identified at each stage. The amplified risk leads to behavioral responses, which, in turn, result in secondary impacts. Models are presented that portray the elements and linkages in the proposed conceptual framework

  13. Desert Amplification in a Warming Climate.

    Science.gov (United States)

    Zhou, Liming

    2016-01-01

    Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950-2099 by large-scale ecoregion and find strongest warming consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a warming climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global warming associated with water vapor feedbacks over land in low- and mid- latitudes where surface warming rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus extremely sensitive to changes of water vapor. PMID:27538725

  14. Controversies in Lung Cancer Screening.

    Science.gov (United States)

    Gill, Ritu R; Jaklitsch, Michael T; Jacobson, Francine L

    2016-02-01

    There remains an extensive debate over lung cancer screening, with lobbying for and against screening for very compelling reasons. The National Lung Screening Trial, International Early Lung Cancer Program, and other major screening studies favor screening with low-dose CT scans and have shown a reduction in lung cancer-specific mortality. The increasing incidence of lung cancer and the dismal survival rate for advanced disease despite improved multimodality therapy have sparked an interest in the implementation of national lung cancer screening. Concerns over imaging workflow, radiation dose, management of small nodules, overdiagnosis bias, lead-time and length-time bias, emerging new technologies, and cost-effectiveness continue to be debated. The authors address each of these issues as they relate to radiologic practice. PMID:26846531

  15. Electromagnetic waves amplification in a coaxial triode with virtual cathode

    Energy Technology Data Exchange (ETDEWEB)

    Grigoryev, V.P.; Antoshkin, M.Y.; Koval, T.V.; Kuryakov, A.M. [Tomsk Politechnical Univ. (Russian Federation)

    1995-11-01

    The present paper presents the results of analytical and numerical investigations on the amplification of microwaves in the vircator triode of coaxial making. The range of a parameters of the greatest amplification was define for TH and TE-modes.

  16. Squeezed states and quantum-mechanical parametric amplification

    International Nuclear Information System (INIS)

    The relation of a previous paper on the parametric amplification of a quantum oscillator to squeezed states is described. In particular, we show that in general the amplification factor is also the ''squeezing factor'' of the final state. 8 refs

  17. HCC screening; HCC-Screening

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, T. [Charite-Unversitaetsmedizin,Freie Universitaet und Humboldt-Universitaet zu Berlin, Klinik und Hochschulambulanz fuer Radiologie und Nuklearmedizin,Campus Benjamin Franklin, Berlin (Germany)

    2008-01-15

    Hepatocellular carcinoma (HCC) is one of the most frequently diagnosed tumour diseases throughout the world. In the vast majority of cases those affected are high-risk patients with chronic viral hepatitis and/or liver cirrhosis, which means there is a clearly identifiable target group for HCC screening. With resection, transplantation, and interventional procedures for local ablation, following early diagnosis curative treatment options are available with which 5-year survival rates of over 60% can be reached. Such early diagnosis is a reality only in a minority of patients, however, and in the majority of cases the disease is already in an advanced stage at diagnosis. One of the objects of HCC screening is diagnosis in an early stage when curative treatment is still possible. Precisely this is achieved by screening, so that the proportion of patients treated with curative intent is decisively higher. There is not yet any clear evidence as to whether this leads to a lowering of the mortality of HCC. As lower mortality is the decisive indicator of success for a screening programme the benefit of HCC screening has so far been neither documented nor refuted. Nonetheless, in large regions of the world it is the practice for high-risk patients to undergo HCC screening in the form of twice-yearly ultrasound examination and determination of AFP. (orig.) [German] Das hepatozellulaere Karzinom (HCC) ist eine der weltweit haeufigsten Tumorerkrankungen. Es tritt in der grossen Mehrzahl der Faelle bei Hochrisikopatienten mit chronischer Virushepatitis bzw. Leberzirrhose auf, woraus sich eine klar identifizierbare Zielgruppe fuer das HCC-Screening ergibt. Mit der Resektion, der Transplantation und interventionellen lokal ablativen Verfahren stehen bei rechtzeitiger Diagnosestellung kurative Therapieoptionen zur Verfuegung, die 5-Jahres-Ueberlebensraten von >60% erreichen. Diese rechtzeitige Diagnosestellung erfolgt jedoch nur bei einer Minderzahl der Patienten, waehrend die

  18. Integrated Microfluidic Nucleic Acid Isolation, Isothermal Amplification, and Amplicon Quantification

    Directory of Open Access Journals (Sweden)

    Michael G. Mauk

    2015-10-01

    Full Text Available Microfluidic components and systems for rapid (<60 min, low-cost, convenient, field-deployable sequence-specific nucleic acid-based amplification tests (NAATs are described. A microfluidic point-of-care (POC diagnostics test to quantify HIV viral load from blood samples serves as a representative and instructive example to discuss the technical issues and capabilities of “lab on a chip” NAAT devices. A portable, miniaturized POC NAAT with performance comparable to conventional PCR (polymerase-chain reaction-based tests in clinical laboratories can be realized with a disposable, palm-sized, plastic microfluidic chip in which: (1 nucleic acids (NAs are extracted from relatively large (~mL volume sample lysates using an embedded porous silica glass fiber or cellulose binding phase (“membrane” to capture sample NAs in a flow-through, filtration mode; (2 NAs captured on the membrane are isothermally (~65 °C amplified; (3 amplicon production is monitored by real-time fluorescence detection, such as with a smartphone CCD camera serving as a low-cost detector; and (4 paraffin-encapsulated, lyophilized reagents for temperature-activated release are pre-stored in the chip. Limits of Detection (LOD better than 103 virons/sample can be achieved. A modified chip with conduits hosting a diffusion-mode amplification process provides a simple visual indicator to readily quantify sample NA template. In addition, a companion microfluidic device for extracting plasma from whole blood without a centrifuge, generating cell-free plasma for chip-based molecular diagnostics, is described. Extensions to a myriad of related applications including, for example, food testing, cancer screening, and insect genotyping are briefly surveyed.

  19. Recombinase Polymerase Amplification Assay for Rapid Diagnostics of Dengue Infection.

    Directory of Open Access Journals (Sweden)

    Ahmed Abd El Wahed

    Full Text Available Over 2.5 billion people are exposed to the risk of contracting dengue fever (DF. Early diagnosis of DF helps to diminish its burden on public health. Real-time reverse transcription polymerase amplification assays (RT-PCR are the standard method for molecular detection of the dengue virus (DENV. Real-time RT-PCR analysis is not suitable for on-site screening since mobile devices are large, expensive, and complex. In this study, two RT-recombinase polymerase amplification (RT-RPA assays were developed to detect DENV1-4.Using two quantitative RNA molecular standards, the analytical sensitivity of a RT-RPA targeting the 3´non-translated region of DENV1-4 was found to range from 14 (DENV4 to 241 (DENV1-3 RNA molecules detected. The assay was specific and did not cross detect other Flaviviruses. The RT-RPA assay was tested in a mobile laboratory combining magnetic-bead based total nucleic acid extraction and a portable detection device in Kedougou (Senegal and in Bangkok (Thailand. In Kedougou, the RT-RPA was operated at an ambient temperature of 38 °C with auxiliary electricity tapped from a motor vehicle and yielded a clinical sensitivity and specificity of 98% (n=31 and 100% (n=23, respectively. While in the field trial in Bangkok, the clinical sensitivity and specificity were 72% (n=90 and 100%(n=41, respectively.During the first 5 days of infection, the developed DENV1-4 RT-RPA assays constitute a suitable accurate and rapid assay for DENV diagnosis. Moreover, the use of a portable fluorescence-reading device broadens its application potential to the point-of-care for outbreak investigations.

  20. The national protocol for paediatric amplification in Australia.

    Science.gov (United States)

    King, Alison M

    2010-01-01

    This document describes the national protocol for the selection, fitting, verification, and evaluation of amplification for hearing-impaired children in Australia. It also outlines the approach to management of children who have auditory neuropathy spectrum disorder, children who have mild and unilateral hearing loss, and children who require cochlear implantation. Audiological management of all Australian citizens and permanent residents under twenty-one years of age who have a hearing loss is carried out by the national hearing service provider, Australian Hearing. It is funded by the Australian Government's Hearing Services Program to provide fully subsidised hearing aids, frequency modulated (FM) systems and ongoing audiological management. All hearing aids for children are multi-channel devices that offer wide dynamic range compression, directional microphone technology and feedback cancellation as well as access to multiple listening programs, telecoil and audio-input facilities. Hearing aid gain, frequency response and maximum power output are derived according to the NAL-NL1 prescription procedure and verified using real ear measurements. Amplification benefit is evaluated using a range of speech perception tests and functional assessment questionnaires. PMID:19919326

  1. A new evolutionary theory deduced mathematically from entropy amplification

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new evolutionary theory which is able to unite the present evolutionary debates is deduced mathematically from the principle of entropy amplification.It suggests that the extensive evolution is driven by the amplification of entropy,or microscopic diversity,and the biological evolution is driven by the amplification of biodiversity.Forming high hierarchies is the most important way for the amplification and brings out spontaneously three kinds of selection.This theory has some positive cultural meanings.

  2. Methods and Compositions for Amplification and Detection of microRNAs (miRNAs) and Noncoding RNAs (ncRNAs) Using the Signature Sequence Amplification Method (SSAM)

    OpenAIRE

    Ginsberg, Stephen D.; Che, Shaoli

    2014-01-01

    The signature sequence amplification method (SSAM) described herein is an approach for amplifying noncoding RNA (ncRNA), microRNA (miRNA), and small polynucleotide sequences. A key point of the SSAM technology is the generation of signature sequences. The signature sequences include target sequences (miRNA, ncRNA, and/or any small polynucleotide sequence) flanked by two DNA fragments. Target sequences can be amplified through DNA synthesis, RNA synthesis, or the combination of DNA and RNA syn...

  3. Assessment of whole genome amplification-induced bias through high-throughput, massively parallel whole genome sequencing

    Directory of Open Access Journals (Sweden)

    Plant Ramona N

    2006-08-01

    Full Text Available Abstract Background Whole genome amplification is an increasingly common technique through which minute amounts of DNA can be multiplied to generate quantities suitable for genetic testing and analysis. Questions of amplification-induced error and template bias generated by these methods have previously been addressed through either small scale (SNPs or large scale (CGH array, FISH methodologies. Here we utilized whole genome sequencing to assess amplification-induced bias in both coding and non-coding regions of two bacterial genomes. Halobacterium species NRC-1 DNA and Campylobacter jejuni were amplified by several common, commercially available protocols: multiple displacement amplification, primer extension pre-amplification and degenerate oligonucleotide primed PCR. The amplification-induced bias of each method was assessed by sequencing both genomes in their entirety using the 454 Sequencing System technology and comparing the results with those obtained from unamplified controls. Results All amplification methodologies induced statistically significant bias relative to the unamplified control. For the Halobacterium species NRC-1 genome, assessed at 100 base resolution, the D-statistics from GenomiPhi-amplified material were 119 times greater than those from unamplified material, 164.0 times greater for Repli-G, 165.0 times greater for PEP-PCR and 252.0 times greater than the unamplified controls for DOP-PCR. For Campylobacter jejuni, also analyzed at 100 base resolution, the D-statistics from GenomiPhi-amplified material were 15 times greater than those from unamplified material, 19.8 times greater for Repli-G, 61.8 times greater for PEP-PCR and 220.5 times greater than the unamplified controls for DOP-PCR. Conclusion Of the amplification methodologies examined in this paper, the multiple displacement amplification products generated the least bias, and produced significantly higher yields of amplified DNA.

  4. Plasmonic Terahertz Amplification in Graphene-Based Asymmetric Hyperbolic Metamaterial

    Directory of Open Access Journals (Sweden)

    Igor Nefedov

    2015-05-01

    Full Text Available We propose and theoretically explore terahertz amplification, based on stimulated generation of plasmons in graphene asymmetric hyperbolic metamaterials (AHMM, strongly coupled to terahertz radiation. In contrast to the terahertz amplification in resonant nanocavities, AHMM provides a wide-band THz amplification without any reflection in optically thin graphene multilayers.

  5. A novel cell-based duplex high-throughput screening assay combining fluorescent Ca(2+) measurement with homogeneous time-resolved fluorescence technology.

    Science.gov (United States)

    Kiss, László; Cselenyák, Attila; Varga, Ágnes; Visegrády, András

    2016-08-15

    Cell-based assays for G-protein-coupled receptor (GPCR) activation applied in high-throughput screening (HTS) monitor various readouts for second messengers or intracellular effectors. Recently, our understanding of diverging signaling pathways downstream of receptor activation and the capability of small molecules to selectively modulate signaling routes has increased substantially, underlining the importance of selecting appropriate readouts in cellular functional screens. To minimize the rate of false negatives in large-scale screening campaigns, it is crucial to maximize the chance of a ligand being detected, and generally applicable methods for detecting multiple analytes from a single well might serve this purpose. The few assays developed so far based on multiplexed GPCR readouts are limited to only certain applications and usually rely on genetic manipulations hindering screening in native or native-like cellular systems. Here we describe a more generally applicable and HTS-compatible homogeneous assay based on the combination of fluorometric detection of [Ca(2+)] with subsequent homogeneous time-resolved fluorescence (HTRF) cAMP readout in the same well. Besides describing development and validation of the assay, using a cell line recombinantly expressing the human PTH1 receptor screening of a small library is also presented, demonstrating the robustness and HTS compatibility of the novel paradigm. PMID:27235172

  6. Study on Application of Screening Technology to Urban River Dredging Sludge Disposal%筛分技术在城市河道疏浚污泥处置中的应用研究

    Institute of Scientific and Technical Information of China (English)

    杨玉岭; 黄锦城; 赖佑贤

    2015-01-01

    The paper studies the application of screening technology to urban studies river sludge. Based on the analysis of the engineering properties of urban river sludge, the application of different screening equipment to urban is discussed comprehensively. Meanwhile, the screening technology is applied to the project practice, which has obtained a good effect, and provides reference for the problems encountered in the urban river sludge disposal.%对筛分技术应用于城市河道污泥进行探索研究,在对城市河道污泥的工程特性分析的基础上,对不同的筛分设备用于城市河道污泥进行全面分析,并将筛分技术应用于工程实践中,取得了良好的效果,为城市河道污泥预处置中遇到的难题提供了良好借鉴。

  7. Carotid Artery Screening

    Science.gov (United States)

    ... Resources Professions Site Index A-Z Carotid Artery Screening What is carotid artery screening? Who should consider ... about carotid artery screening? What is carotid artery screening? Screening examinations are tests performed to find disease ...

  8. Preconception Carrier Screening

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Preconception Carrier Screening Home For Patients Search FAQs Preconception Carrier Screening ... Screening FAQ179, August 2012 PDF Format Preconception Carrier Screening Pregnancy What is preconception carrier screening? What is ...

  9. Screening for Specific Phobias

    Science.gov (United States)

    ... Screening for Posttraumatic Stress Disorder (PTSD) Screening for Social Anxiety Disorder Screening for Specific Phobias Screening for an Anxiety Disorder: Children Screening for an Anxiety Disorder: Family Member Self- ...

  10. Detection of telomerase activity by combination of telomeric repeat amplification protocol and electrochemiluminescence assay

    Institute of Scientific and Technical Information of China (English)

    Xiao Ming Zhou; Li Jia

    2008-01-01

    A highly sensitive telomerase detection method that combines telomeric repeat amplification protocol (TRAP) and magnetic beads based electrochemiluminescence (ECL) assay has been developed. Briefly, telomerase recognizes biotinylated telomerase synthesis primer (B-TS) and synthesizes extension products, which then serve as the templates for PCR amplification using B-TS as the forward primer and Iris-(2'2'-bipyridyl) ruthenium (TBR) labeled ACX (TBR-ACX) as the reversed primer. The amplified product is captured on streptavidin-coated paramagnetic beads and detected by ECL. Telomerase positive HeLa cells were used to validate the feasibility of the method. The experimental results showed down to 10 cancer cells can be detected easily. The method is a useful tool for telomerase activity analysis due to its sensitivity, rapidity, safety, high throughput, and low cost. It can be used for screening a large amount of clinical samples.

  11. Luminescent screens

    International Nuclear Information System (INIS)

    Luminescent screens which are useful for such purposes as intensifying screens for radiographs are comprised of a support bearing a layer of finely divided particles of a phosphor dispersed in a cross-linked polymeric matrix formed by heat-curing of a coating composition comprising an unsaturated cross-linkable polymer, a polymerizable acrylic monomer, a thermoplastic polyurethane elastomer, and a heat-activatable polymerization initiator. The phosphor layer includes voids formed by evaporation of an evaporable component which is present in the coating composition from which such layer is formed. (author)

  12. Screen Printed Metallization of Silicon Solar Cells

    OpenAIRE

    Govaerts, R.; Van Overstraeten, R.; Mertens, R.; Ph. Lauwers; Frisson, L.

    1980-01-01

    This paper presents a screen printing process for the metallization of silicon solar cells. The physics and construction of a classical solar cell are reviewed. The results obtained with a screen printing process are comparable with other, more expensive technologies. This technology does not introduce an additional contact resistance on silicon. The process optimization and the influence of different parameters are discussed.

  13. Diffusive shock acceleration and magnetic field amplification

    CERN Document Server

    Schure, K M; Drury, L O'C; Bykov, A M

    2012-01-01

    Diffusive shock acceleration is the theory of particle acceleration through multiple shock crossings. In order for this process to proceed at a rate that can be reconciled with observations of high-energy electrons in the vicinity of the shock, and for cosmic rays protons to be accelerated to energies up to observed galactic values, significant magnetic field amplification is required. In this review we will discuss various theories on how magnetic field amplification can proceed in the presence of a cosmic ray population. On both short and long scales, cosmic ray streaming can induce instabilities that act to amplify the magnetic field. Developments in this area that have occurred over the past decade are the main focus of this paper.

  14. Parametric amplification in low density plasma sheath

    International Nuclear Information System (INIS)

    Nonlinear sheath capacitance properties in low density plasma, whose propose is to produce the parametric amplification on the RF signal in the high frequency band (H.F.) are used. The experiment has been carried out in the Mirror Linear Device LISA of the Universidade Federal Fluminense, where a helium plasma was produced by the radiofrequency source built at UFF with a power which can be varied from 10 watts to 100 watts. The experimental results obtained show that it is practicable the construction of the parametric amplifier with high gain of the selectively, which is very good in the amplification of the weak signals, where the gain factor and the relation between signal versus noise are fundamental. (Author)

  15. Weak-value amplification: state of play

    Directory of Open Access Journals (Sweden)

    Knee George C.

    2016-01-01

    Full Text Available Weak values arise in quantum theory when the result of a weak measurement is conditioned on a subsequent strong measurement. The majority of the trials are discarded, leaving only very few successful events. Intriguingly those can display a substantial signal amplification. This raises the question of whether weak values carry potential to improve the performance of quantum sensors, and indeed a number of impressive experimental results suggested this may be the case. By contrast, recent theoretical studies have found the opposite: using weak-values to obtain an amplification generally worsens metrological performance. This survey summarises the implications of those studies, which call for a reappraisal of weak values’ utility and for further work to reconcile theory and experiment.

  16. Hearing Screening

    Science.gov (United States)

    Johnson-Curiskis, Nanette

    2012-01-01

    Hearing levels are threatened by modern life--headsets for music, rock concerts, traffic noises, etc. It is crucial we know our hearing levels so that we can draw attention to potential problems. This exercise requires that students receive a hearing screening for their benefit as well as for making the connection of hearing to listening.

  17. Applicability of the ParaDNA(®) Screening System to Seminal Samples.

    Science.gov (United States)

    Tribble, Nicholas D; Miller, Jamie A D; Dawnay, Nick; Duxbury, Nicola J

    2015-05-01

    Seminal fluid represents a common biological material recovered from sexual assault crime scenes. Such samples can be prescreened using different techniques to determine cell type and relative amount before submitting for full STR profiling. The ParaDNA(®) Screening System is a novel forensic test which identifies the presence of DNA through amplification and detection of two common STR loci (D16S539 and TH01) and the Amelogenin marker. The detection of the Y allele in samples could provide a useful tool in the triage and submission of sexual assault samples by enforcement authorities. Male template material was detected on a range of common sexual assault evidence items including cotton pillow cases, condoms, swab heads and glass surfaces and shows a detection limit of 1 in 1000 dilution of neat semen. These data indicate this technology has the potential to be a useful tool for the detection of male donor DNA in sexual assault casework. PMID:25739746

  18. Fidelity of DNA polymerases in DNA amplification.

    OpenAIRE

    Keohavong, P; Thilly, W G

    1989-01-01

    Denaturing gradient gel electrophoresis (DGGE) was used to separate and isolate the products of DNA amplification by polymerase chain reaction (PCR). The strategy permitted direct enumeration and identification of point mutations created by T4, modified T7, Klenow fragment of polymerase I, and Thermus aquaticus (Taq) DNA polymerases. Incorrectly synthesized sequences were separated from the wild type by DGGE as mutant/wild-type heteroduplexes and the heteroduplex fraction was used to calculat...

  19. Introduction to Quantum Noise, Measurement and Amplification

    OpenAIRE

    Clerk, A. A.; Devoret, M. H.; Girvin, S. M.; Marquardt, F.; Schoelkopf, R. J.

    2008-01-01

    The topic of quantum noise has become extremely timely due to the rise of quantum information physics and the resulting interchange of ideas between the condensed matter and AMO/quantum optics communities. This review gives a pedagogical introduction to the physics of quantum noise and its connections to quantum measurement and quantum amplification. After introducing quantum noise spectra and methods for their detection, we describe the basics of weak continuous measurements. Particular atte...

  20. Colossal magnetoelectric effect induced by parametric amplification

    Science.gov (United States)

    Wang, Yi; Onuta, Tiberiu-Dan; Long, Christian J.; Geng, Yunlong; Takeuchi, Ichiro

    2015-11-01

    We describe the use of parametric amplification to substantially increase the magnetoelectric (ME) coefficient of multiferroic cantilevers. Parametric amplification has been widely used in sensors and actuators based on optical, electronic, and mechanical resonators to increase transducer gain. In our system, a microfabricated mechanical cantilever with a magnetostrictive layer is driven at its fundamental resonance frequency by an AC magnetic field. The resulting actuation of the cantilever at the resonance frequency is detected by measuring the voltage across a piezoelectric layer in the same cantilever. Concurrently, the spring constant of the cantilever is modulated at twice the resonance frequency by applying an AC voltage across the piezoelectric layer. The spring constant modulation results in parametric amplification of the motion of the cantilever, yielding a gain in the ME coefficient. Using this method, the ME coefficient was amplified from 33 V/(cm Oe) to 2.0 MV/(cm Oe), an increase of over 4 orders of magnitude. This boost in the ME coefficient directly resulted in an enhancement of the magnetic field sensitivity of the device from 6.0 nT /√{Hz } to 1.0 nT /√{Hz } . The enhancement in the ME coefficient and magnetic field sensitivity demonstrated here may be beneficial for a variety actuators and sensors based on resonant multiferroic devices.

  1. A terminating-type MEMS microwave power sensor and its amplification system

    International Nuclear Information System (INIS)

    A terminating-type MEMS microwave power sensor and its amplification system are presented in this paper. A SPICE model is introduced to simulate temperature distribution of this power sensor, and the model has a reference value to estimate the sensitivity of the power sensor. This power sensor is designed and fabricated using MEMS technology and the GaAs MMIC process. It is measured in the frequency range up to 20 GHz with an input power in the 0 to 50 mW range. Over the 50 mW dynamic range, the sensitivity is about 0.29, 0.24 and 0.22 mV mW−1 at 5, 10 and 15 GHz, respectively. The output voltage of the power sensor ranges from 0.64 to 15.2 mV at 5 GHz. After amplification, the output voltage ranges from 0.19 to 6.56 V. The amplification gain is about 437.5, and the sensitivity is increased to 1274 mV mW−1. At 15 GHz, the output voltage of the power sensor ranges from 0.57 to 11.69 mV. After amplification, the output voltage ranges from 0.146 to 5.02 V. The amplification gain is about 438, and the sensitivity is increased to 974.8 mV mW−1. The measurement results show that the amplification system can amplify the output weak signal of the power sensor well and have good linearity.

  2. Technology

    Directory of Open Access Journals (Sweden)

    Xu Jing

    2016-01-01

    Full Text Available The traditional answer card reading method using OMR (Optical Mark Reader, most commonly, OMR special card special use, less versatile, high cost, aiming at the existing problems proposed a method based on pattern recognition of the answer card identification method. Using the method based on Line Segment Detector to detect the tilt of the image, the existence of tilt image rotation correction, and eventually achieve positioning and detection of answers to the answer sheet .Pattern recognition technology for automatic reading, high accuracy, detect faster

  3. Loop mediated isothermal amplification: An innovative gene amplification technique for animal diseases.

    Science.gov (United States)

    Sahoo, Pravas Ranjan; Sethy, Kamadev; Mohapatra, Swagat; Panda, Debasis

    2016-05-01

    India being a developing country mainly depends on livestock sector for its economy. However, nowadays, there is emergence and reemergence of more transboundary animal diseases. The existing diagnostic techniques are not so quick and with less specificity. To reduce the economy loss, there should be a development of rapid, reliable, robust diagnostic technique, which can work with high degree of sensitivity and specificity. Loop mediated isothermal amplification assay is a rapid gene amplification technique that amplifies nucleic acid under an isothermal condition with a set of designed primers spanning eight distinct sequences of the target. This assay can be used as an emerging powerful, innovative gene amplification diagnostic tool against various pathogens of livestock diseases. This review is to highlight the basic concept and methodology of this assay in livestock disease. PMID:27284221

  4. DNA Amplification from Pin Mounted Bumble Bees (Bombus) in a Museum Collection: Effects of Fragment Size and Specimen Age on Successful PCR

    Science.gov (United States)

    Historic data in the form of pinned specimens in entomological collections offer the potential to determine trends in genetic diversity of bumble bees (Bombus). We screened eight microsatellite loci for amplification success in pinned bumble bee specimens from the U.S. National Pollinating Insects C...

  5. BeeDoctor, a versatile MLPA-based diagnostic tool for screening bee viruses.

    Directory of Open Access Journals (Sweden)

    Lina De Smet

    Full Text Available The long-term decline of managed honeybee hives in the world has drawn significant attention to the scientific community and bee-keeping industry. A high pathogen load is believed to play a crucial role in this phenomenon, with the bee viruses being key players. Most of the currently characterized honeybee viruses (around twenty are positive stranded RNA viruses. Techniques based on RNA signatures are widely used to determine the viral load in honeybee colonies. High throughput screening for viral loads necessitates the development of a multiplex polymerase chain reaction approach in which different viruses can be targeted simultaneously. A new multiparameter assay, called "BeeDoctor", was developed based on multiplex-ligation probe dependent amplification (MLPA technology. This assay detects 10 honeybee viruses in one reaction. "BeeDoctor" is also able to screen selectively for either the positive strand of the targeted RNA bee viruses or the negative strand, which is indicative for active viral replication. Due to its sensitivity and specificity, the MLPA assay is a useful tool for rapid diagnosis, pathogen characterization, and epidemiology of viruses in honeybee populations. "BeeDoctor" was used for screening 363 samples from apiaries located throughout Flanders; the northern half of Belgium. Using the "BeeDoctor", virus infections were detected in almost eighty percent of the colonies, with deformed wing virus by far the most frequently detected virus and multiple virus infections were found in 26 percent of the colonies.

  6. BeeDoctor, a versatile MLPA-based diagnostic tool for screening bee viruses.

    Science.gov (United States)

    De Smet, Lina; Ravoet, Jorgen; de Miranda, Joachim R; Wenseleers, Tom; Mueller, Matthias Y; Moritz, Robin F A; de Graaf, Dirk C

    2012-01-01

    The long-term decline of managed honeybee hives in the world has drawn significant attention to the scientific community and bee-keeping industry. A high pathogen load is believed to play a crucial role in this phenomenon, with the bee viruses being key players. Most of the currently characterized honeybee viruses (around twenty) are positive stranded RNA viruses. Techniques based on RNA signatures are widely used to determine the viral load in honeybee colonies. High throughput screening for viral loads necessitates the development of a multiplex polymerase chain reaction approach in which different viruses can be targeted simultaneously. A new multiparameter assay, called "BeeDoctor", was developed based on multiplex-ligation probe dependent amplification (MLPA) technology. This assay detects 10 honeybee viruses in one reaction. "BeeDoctor" is also able to screen selectively for either the positive strand of the targeted RNA bee viruses or the negative strand, which is indicative for active viral replication. Due to its sensitivity and specificity, the MLPA assay is a useful tool for rapid diagnosis, pathogen characterization, and epidemiology of viruses in honeybee populations. "BeeDoctor" was used for screening 363 samples from apiaries located throughout Flanders; the northern half of Belgium. Using the "BeeDoctor", virus infections were detected in almost eighty percent of the colonies, with deformed wing virus by far the most frequently detected virus and multiple virus infections were found in 26 percent of the colonies. PMID:23144717

  7. Loop-mediated Isothermal Amplification Assay to Rapidly Detect Wheat Streak Mosaic Virus in Quarantined Plants

    Directory of Open Access Journals (Sweden)

    Siwon Lee

    2015-12-01

    Full Text Available We developed a loop-mediated isothermal amplification (LAMP method to rapidly diagnose Wheat streak mosaic virus (WSMV during quarantine inspections of imported wheat, corn, oats, and millet. The LAMP method was developed as a plant quarantine inspection method for the first time, and its simplicity, quickness, specificity and sensitivity were verified compared to current reverse transcription-polymerase chain reaction (RT-PCR and nested PCR quarantine methods. We were able to quickly screen for WSMV at quarantine sites with many test samples; thus, this method is expected to contribute to plant quarantine inspections.

  8. Forensic mass screening using mtDNA.

    Science.gov (United States)

    Szibor, Reinhard; Plate, Ines; Schmitter, Herrmann; Wittig, Holger; Krause, Dieter

    2006-11-01

    At the forensic autopsy of a sexual murder victim, some trace hairs, possibly belonging to the perpetrator, were saved. Initially, the analysis of a pubic hair shaft only revealed the presence of the mitochondrial (mt) DNA haplotype profile consisting of the (CA)(6) allele and the complete hypervariable region 1 (HV1) and 2 (HV2) sequence. Later, typing of some further telogene trace hairs, which had been stored for several years, yielded a nuclear short tandem repeat (STR) profile. We used both the mtDNA haplotype and the STR profile to start a DNA mass screening project involving 2,335 male citizens of the relevant communities. MtDNA screening was carried out by using the CA repeat amplification in combination with an SNP typing procedure based on the restriction site analysis of amplified d-loop sequences. The aim of our paper is to put mass screening with mtDNA up for discussion. PMID:16583247

  9. Complementary RNA amplification methods enhance microarray identification of transcripts expressed in the C. elegans nervous system

    Directory of Open Access Journals (Sweden)

    Levy Shawn

    2008-02-01

    Full Text Available Abstract Background DNA microarrays provide a powerful method for global analysis of gene expression. The application of this technology to specific cell types and tissues, however, is typically limited by small amounts of available mRNA, thereby necessitating amplification. Here we compare microarray results obtained with two different methods of RNA amplification to profile gene expression in the C. elegans larval nervous system. Results We used the mRNA-tagging strategy to isolate transcripts specifically from C. elegans larval neurons. The WT-Ovation Pico System (WT-Pico was used to amplify 2 ng of pan-neural RNA to produce labeled cDNA for microarray analysis. These WT-Pico-derived data were compared to microarray results obtained with a labeled aRNA target generated by two rounds of In Vitro Transcription (IVT of 25 ng of pan-neural RNA. WT-Pico results in a higher fraction of present calls than IVT, a finding consistent with the proposal that DNA-DNA hybridization results in lower mismatch signals than the RNA-DNA heteroduplexes produced by IVT amplification. Microarray data sets from these samples were compared to a reference profile of all larval cells to identify transcripts with elevated expression in neurons. These results were validated by the high proportion of known neuron-expressed genes detected in these profiles and by promoter-GFP constructs for previously uncharacterized genes in these data sets. Together, the IVT and WT-Pico methods identified 2,173 unique neuron-enriched transcripts. Only about half of these transcripts (1,044, however, are detected as enriched by both IVT and WT-Pico amplification. Conclusion We show that two different methods of RNA amplification, IVT and WT-Pico, produce valid microarray profiles of gene expression in the C. elegans larval nervous system with a low rate of false positives. However, our results also show that each method of RNA amplification detects a unique subset of bona fide neural

  10. Spellbinding and crooning: sound amplification, radio, and political rhetoric in international comparative perspective, 1900-1945.

    Science.gov (United States)

    Wijfjes, Huub

    2014-01-01

    This article researches in an interdisciplinary way the relationship of sound technology and political culture at the beginning of the twentieth century. It sketches the different strategies that politicians--Franklin D. Roosevelt, Adolf Hitler, Winston Churchill, and Dutch prime minister Hendrikus Colijn--found for the challenges that sound amplification and radio created for their rhetoric and presentation. Taking their different political styles into account, the article demonstrates that the interconnected technologies of sound amplification and radio forced a transition from a spellbinding style based on atmosphere and pathos in a virtual environment to "political crooning" that created artificial intimacy in despatialized simultaneity. Roosevelt and Colijn created the best examples of this political crooning, while Churchill and Hitler encountered problems in this respect. Churchill's radio successes profited from the special circumstances during the first period of World War II. Hitler's speeches were integrated into a radio regime trying to shape, with dictatorial powers, a national socialistic community of listeners. PMID:24988797

  11. 广州亚运会风帆状折叠升降LED显示屏安装技术%Installation Technology of Folding and Lifting LED Display Screen with Sail-shaped in Guangzhou Asian Games

    Institute of Scientific and Technical Information of China (English)

    黄东阳; 彭文海; 黎丁; 李仕许

    2012-01-01

    The folding and lifting LED display screen with sail-shape plays the most important part in the ceremony of 16th Guangzhou Asian Games, and it is very difficult to construct. Based on the engineering characteristics, key technologies including flexible connection technology between the two folding plates, lifting and limit system, precise positioning technology of guiding trolley and synthesis installation technology of the sail frame are studied and tackled in this paper. Important difficulties in the construction were overcome and excellent effectiveness were gained. The construction technology can provide reference for the similar engineering projects.%风帆状折叠升降LED显示屏在第十六届广州亚洲运动会开闭幕式上扮演了的最重要的角色,由于其全新创意导致安装施工难度大.针对工程特点,通过对折叠风帆架板块间的柔性连接技术、提升及限位系统、导向小车精确定位技术、风帆架综合安装技术等关键技术的研究攻关,解决项目施工的重大难点,取得了良好的效果,同时为日后类似工程施工提供参考.

  12. Eletrodos fabricados por "silk-screen" Screen-printed electrodes

    Directory of Open Access Journals (Sweden)

    Valberes B. Nascimento

    1998-10-01

    Full Text Available A review dealing with the use of screen-printing technology to manufacture disposable electrodes is presented, covering in details virtually all the publications in the area up to early 1997 and including 206 references. The elements and different strategies on constructing modified electrodes are highlighted. Commercial and Home-made ink recipes are discussed. Microelectrode arrays, built by the combination of photostructuring and screen-printing technologies to the mass production of advanced disposable sensors, are also discussed. Future research trends are predicted.

  13. Solid form screening--a review.

    Science.gov (United States)

    Aaltonen, Jaakko; Allesø, Morten; Mirza, Sabiruddin; Koradia, Vishal; Gordon, Keith C; Rantanen, Jukka

    2009-01-01

    Solid form screening, the activity of generating and analysing different solid forms of an active pharmaceutical ingredient (API), has become an essential part of drug development. The multi-step screening process needs to be designed, performed and evaluated carefully, since the decisions made based on the screening may have consequences on the whole lifecycle of a pharmaceutical product. The selection of the form for development is made after solid form screening. The selection criteria include not only pharmaceutically relevant properties, such as therapeutic efficacy and processing characteristics, but also intellectual property (IP) issues. In this paper, basic principles of solid form screening are reviewed, including the methods used in experimental screening (generation, characterisation and analysis of solid forms, data mining tools, and high-throughput screening technologies) as well as basics of computational methods. Differences between solid form screening strategies of branded and generic pharmaceutical manufacturers are also discussed. PMID:18715549

  14. Silicon detectors with internal amplification based on functionally integrated structures

    International Nuclear Information System (INIS)

    Full text: A new coordinate-sensitive semiconductor silicon detector capable both to determine particle coordinates and detect single-charged relativistic particles and x-rays is considered. It is proposed to improve the functional integration of VLSI circuit element base and achieve a high internal amplification directly inside the detector chip. To resolve these problems, we use functionally integrated active pixels made on the basis of a hybrid of p-i-n diode and bipolar transistor manufactured with using a specific technology. Bipolar coordinate-sensitive detectors could provide the information access time less than 5 ns, coordinate accuracy better than 5050 mm2, sensitivity higher than that of p-i-n diodes by a factor of 100 or more. Single pixels are joined into a 1010 mm2 matrix. n-Si wafers with a specific resistance r ≥ 5 kOhmcm and carrier lifetime t = 2500 ms have been used as a basis. The ion-implantation and following annealing are used to create active areas. To make the shallow-junction emitter, arsenic ions were implanted into polysilicon (Si) with a (1-2)1016 cm-2 dose and then were diffused in substrate; the p--base area was formed with the boron implantation; p+ region was created with inserting boron ions into the substrate. For gettering, phosphorus ions were implanted into the wafer back side. The detectors manufactured are characterized by dark currents of few nano amperes and breakdown voltage of ∼ 250 V. Features of detectors have been studied with using particle sources (238Pu, 239Pu, and 226Ra). All the structures have demonstrated an internal amplification. For example, some structure shows a 0.57-V spectral maximum produced by 239Pu (5.105 MeV) at 20-V power supply voltage, i.e. an amplification factor of 250 is achieved; half-amplitude maximum width is 16%. Output signal amplitudes and resolution depend on magnitude of applied external voltage. (author)

  15. Quadruple screen test

    Science.gov (United States)

    ... screen; Multiple marker screening; AFP plus; Triple screen test; AFP maternal; MSAFP; 4-marker screen ... This test is most often done between the 15th and 22nd weeks of the pregnancy. It is most accurate ...

  16. Autism Screening and Diagnosis

    Science.gov (United States)

    ... Websites About Us Information For... Media Policy Makers Screening and Diagnosis Language: English Español (Spanish) Recommend on ... two steps: Developmental Screening Comprehensive Diagnostic Evaluation Developmental Screening Developmental screening is a short test to tell ...

  17. Amplification Effects and Unconventional Monetary Policies

    Directory of Open Access Journals (Sweden)

    Cécile BASTIDON GILLES

    2012-02-01

    Full Text Available Global financial crises trigger off amplification effects, which allow relatively small shocks to propagate through the whole financial system. For this reason, the range of Central banks policies is now widening beyond conventional monetary policies and lending of last resort. The aim of this paper is to establish a rule for this practice. The model is based on the formalization of funding conditions in various types of markets. We conduct a comprehensive analysis of the “unconventional monetary policies”, and especially quantify government bonds purchases by the Central bank.

  18. Parametric Amplification of Gravitational Fluctuations during Reheating

    International Nuclear Information System (INIS)

    Cosmological perturbations can undergo amplification by parametric resonance during preheating even on scales larger than the Hubble radius, without violating causality. A unified description of gravitational and matter fluctuations is crucial to determine the strength of the instability. To extract specific signatures of the oscillating inflaton field during reheating, it is essential to focus on a variable describing metric fluctuations which is constant in the standard analyses of inflation. For a massive inflaton without self-coupling, we find no additional growth of superhorizon modes during reheating beyond the usual predictions. For a massless self-coupled inflaton, there is a sub-Hubble scale resonance. copyright 1999 The American Physical Society

  19. Gas amplification properties of GEM foils

    International Nuclear Information System (INIS)

    In the framework of the detector concept International Linear Detector for the future accelerator project International Linear Collider, in which electrons and positrons at c. m. energies of 500 GeV are brought to collision, a time projection chamber shall be applied as central track detector. By the application of such a chamber as track detector a three-dimensional reconstruction of the track points is possible. If a particle passes the gas volume within the chamber it ionizises single gas atoms and the arising electrons move after the amplification in the GEM arrangement to the anode, so that a two-dimensional projection of the particle track is possible. The third dimension is calculated from the drift time of the electrons. The advances of this readout system consist therein that a better position resolution than by a multiwire proportional chamber is reached and the back-drifting ions can be strongly suppressed. Aim of this thesis are studies for a GEM module, which shall be used in a large TPC prototype. Concerning different requirements it is valid to compare different GEMs in order to can meet an optimal choice. In a small prototype present at DESY measurements for the acquisition of GEM-describing parameters were performed. The taking into operation of the test TPC was part of this thesis. Tracks were generated by a radioactive source, by means of which the gas amplification was determined. With the measurement arrangement gas-amplifier foils of different kind were compared in view of their amplification properties and their energy resolution power and systematically studied. Five different GEM performances were studied in the test TPC. These foils differ in their geometrical classification parameters, the fabrication process, or the materials. The GEMs produced at CERN possess in comparison with GEMs of the Japanese firm SciEnergy and a GEM of the US-American firm Tech-Etch the best amplification and resolution properties. Furthermore a new GEM framing

  20. Application of proteome technology in screening biomarkers associated with gastric cancer%蛋白质组技术在胃癌相关标志物筛查中的应用

    Institute of Scientific and Technical Information of China (English)

    Chibo Liu; Yong Liang; Haibao Wang; Chunqin Pan

    2008-01-01

    Objective:To initially explore the application of proteome technologies in study of serum,to establish two-dimensional gel electrophoresis (2-DE) profiles of human gastric cancer serum and paired normal serum,and to screen and identify differentially expressed proteins in poorly-differentiated gastric cancer serum and paired normal serum,in which try to find out significant biomarker candidates for gastric cancer.Methods:2-DE was adopted to separate the total proteins of poorly-differentiated gastric cancer serum and paired normal serum.After staining and analyzing by ImageMaster 2D Elite software,the differentially expressed proteins were identified by matrix-assisted laser desorption/ionization-time of flight- mass spectrometry (MALDI-TOF-MS).Results:2-DE serum profiles with high resolution were obtained.Five protein spots were found as differentially-expressed proteins and identified as Serpin B6 (Placental thrombin inhibitor) Cytoplasmic antiproteinase (CAP)(Protease inhibitor6) (P1-6),Septin-1 (LARP) (Serologically defined breast cancer antigen NY-BR-24),Kallikrein-6 precursor (Protease M) (Neurosin) (Zyme) (SP59),Hemoglobin beta chain,Hemoglobin beta chain and Beta-defensin 108 precursor (Beta-defensin 8) (DEFB-8).Conclusion:The differential proteins were demonstrated to present in poorly-differentiated gastric cancer serum and paired normal serum.The molecular biomarkers associated with poorly differentiated gastric cancer could be possibly identified by the high throughput screening proteome technology.

  1. Recombinase polymerase amplification as a promising tool in hepatitis C virus diagnosis

    Institute of Scientific and Technical Information of China (English)

    Hosam; Zaghloul; Mahmoud; El-shahat

    2014-01-01

    Hepatitis C virus(HCV)infection represents a significant health problem and represents a heavy load on some countries like Egypt in which about 20%of the total population are infected.Initial infection is usually asymptomatic and result in chronic hepatitis that give rise to complications including cirrhosis and hepatocellular carcinoma.The management of HCV infection should not only be focus on therapy,but also to screen carrier individuals in order to prevent transmission.In the present,molecular detection and quantification of HCV genome by real time polymerase chain reaction(PCR)represent the gold standard in HCV diagnosis and plays a crucial role in the management of therapeutic regimens.However,real time PCR is a complicated approach and of limited distribution.On the other hand,isothermal DNA amplification techniques have been developed and offer molecular diagnosis of infectious dieses at point-of-care.In this review we discuss recombinase polymerase amplification technique and illustrate its diagnostic value over both PCR and other isothermal amplification techniques.

  2. Detection of genetically modified organisms (GMOs using isothermal amplification of target DNA sequences

    Directory of Open Access Journals (Sweden)

    La Mura Maurizio

    2009-02-01

    Full Text Available Abstract Background The most common method of GMO detection is based upon the amplification of GMO-specific DNA amplicons using the polymerase chain reaction (PCR. Here we have applied the loop-mediated isothermal amplification (LAMP method to amplify GMO-related DNA sequences, 'internal' commonly-used motifs for controlling transgene expression and event-specific (plant-transgene junctions. Results We have tested the specificity and sensitivity of the technique for use in GMO studies. Results show that detection of 0.01% GMO in equivalent background DNA was possible and dilutions of template suggest that detection from single copies of the template may be possible using LAMP. Conclusion This work shows that GMO detection can be carried out using LAMP for routine screening as well as for specific events detection. Moreover, the sensitivity and ability to amplify targets, even with a high background of DNA, here demonstrated, highlights the advantages of this isothermal amplification when applied for GMO detection.

  3. Photoacoustic imaging using lock-in amplification and pulsed fiber lasers

    Science.gov (United States)

    Shi, Wei; Hajireza, Parsin; Zemp, Roger

    2016-03-01

    Photoacoustic (PA) imaging is a non-invasive, non-ionizing imaging technology with high optical contrast between blood and tissue, and with high sensitivity of hemoglobin concentration and oxygen saturation due to different optical absorption spectra resulting from different oxygenation of hemoglobin. Most PA imaging systems implement a nanosecond pulsed laser source as excitation source to induce PA signal, and rely on broadband amplifiers to record time-domain PA signals [1-6]. Some groups, however, have reported using modulated continuous-wave lasers as an excitation source for frequency-domain imaging [7-9]. Frequency-domain imaging offers the potential of lock-in amplification which has sensitivities as low as nV even in noise orders of magnitude higher than the signal. However, although modulated CW sources works for low cost and compact PA imaging, it does not satisfy thermal and stress confinement conditions required for optimal PA signal strength. Here, we investigate a PA methodology using pulsed fiber lasers as excitation laser source combined with lock-in amplification technology. For comparison, we also studied time-domain PA methodology. Phantom studies show that signal-to-noise ratio (SNR) obtained with frequency domain PA imaging is significantly more sensitive than that obtained using time-domain PA imaging when the laser pulse repetition rate (PRR) matches the bandwidth of ultrasound transducer. Therefore, high sensitive PA imaging technology using pulsed fiber laser sources with lock-in amplification may potentially greatly extend the depth of PA imaging.

  4. Screening neonatal

    OpenAIRE

    Urbón Artero, Alfonso; Reig del Moral, Celia

    2006-01-01

    Los autores de este artículo revisan el screening neonatal, desde la descripción por Wilson y Jungner en 1968 de los criterios que hansido aplicados en la detección precoz de enfermedades enel recién nacido, hasta los avances actuales en la medicina genómica que han modificado sustancialmente estas bases. Se comentan los métodos diagnósticos prenatales más utilizados como los analíticos y ultrasonografia prenatal. Se describen los procedimientos que se aplican en la actualidad y se describen ...

  5. Amplification of fluorescence using collinear picosecond optical parametric amplification at degeneracy

    Institute of Scientific and Technical Information of China (English)

    Zhang Jing; Zhang Qiu-Lin; Jiang Man; Zhang Dong-Xiang; Feng Bao-Hua; Zhang Jing-Yuan

    2012-01-01

    We demonstrate the output characteristic of broadband parametric amplification of incoherent light pulses in a 355-nm pumped degenerate picosecond optical parametric amplification with either saturated or unsaturated amplification.The optical parametric amplifier is seeded by the fluorescence generated in a solution of pyridine-1 dye in ethanol.With the saturated amplification,we can obtain high energy incoherent light pulses,whose full widtth at half maximum bandwidth varies from 16 nm to 53 nm for the different phase matching angles near degeneracy.Moreover,the unsaturated bandwidth of the amplified pulses fits well to the calculated result at degeneracy.Selecting s-polarized fluorescence with a Glan-Taylor prism,the maximum bandwidth of the amplified fluorescence is found to be 59 nm for a purely s-polarized seed.The maximum output energy is 0.67 mJ for the optical parametric amplifier.By using an optical filter and compressor,the generated high energy incoherent light has great potential as the incoherent pump,signal or idler wave of a parametric down-conversion process,so that a wave with a high degree of coherence can be generated from an incoherent pump light.

  6. Asymmetric parametric amplification in nonlinear left-handed transmission lines

    OpenAIRE

    Powell, David A.; Ilya V. Shadrivov; Yuri S. Kivshar

    2008-01-01

    We study parametric amplification in nonlinear left-handed transmission lines, which serve as model systems for nonlinear negative index metamaterials. We experimentally demonstrate amplification of a weak pump signal in three regimes: with the signal in the left-handed band, with the signal in the stop band, and with the signal at a defect frequency. In particular, we demonstrate the amplification of the incident wave by up to 15dB in the left-handed regime.

  7. Multiplex allele-specific target amplification based on PCR suppression

    OpenAIRE

    Broude, Natalia E.; Zhang, Lingang; Woodward, Karen; Englert, David; Cantor, Charles R.

    2001-01-01

    We have developed a strategy for multiplex PCR based on PCR suppression. PCR suppression allows DNA target amplification with only one sequence-specific primer per target and a second primer that is common for all targets. Therefore, an n-plex PCR would require only n + 1 primers. We have demonstrated uniform, efficient amplification of targeted sequences in 14-plex PCR. The high specificity of suppression PCR also provides multiplexed amplification with allele specifi...

  8. Loss of KLF14 triggers centrosome amplification and tumorigenesis

    OpenAIRE

    Fan, Guangjian; Sun, Lianhui; Shan, Peipei; Zhang, Xianying; Huan, Jinliang; Li, Dali; Wang, Tingting; Wei, Tingting; Zhang, Xiaohong; Gu, Xiaoyang; Yao, Liangfang; Xuan, Yang; Hou, Zhaoyuan; Cui, Yongping; Cao, Liu

    2015-01-01

    Centrosome amplification is frequent in cancer, but the underlying mechanisms remain unclear. Here we report that disruption of the Kruppel-like factor 14 (KLF14) gene in mice causes centrosome amplification, aneuploidy and spontaneous tumorigenesis. Molecularly, KLF14 functions as a transcriptional repressor of Plk4, a polo-like kinase whose overexpression induces centrosome overduplication. Transient knockdown of KLF14 is sufficient to induce Plk4-directed centrosome amplification. Clinical...

  9. An Improved Analytical Expression for Write Amplification in NAND Flash

    OpenAIRE

    Xiang, Luojie; Kurkoski, Brian

    2011-01-01

    Agarwal et al. gave an closed-form expression for write amplification in NAND flash memory by finding the probability of a page being valid over the whole flash memory. This paper gives an improved analytic expression for write amplification in NAND flash memory by finding the probability of a page being invalid over the block selected for garbage collection. The improved expression uses Lambert W function. Through asymptotic analysis, write amplification is shown to depend on overprovisionin...

  10. Quantum noise in parametric amplification under phase-mismatched conditions

    Science.gov (United States)

    Inoue, K.

    2016-05-01

    This paper studies quantum noise in parametric amplification under phase-mismatched conditions. The equations of motion of the quantum-mechanical field operators, which include phase mismatch under unsaturated conditions are first derived from the Heisenberg equation. Next, the noise figure is evaluated using the solutions of the derived equations. The results indicate that phase mismatch scarcely affects noise property in phase-insensitive amplification while it has a notable effect in case of phase-sensitive amplification.

  11. Development and application of a rapid and visual loop-mediated isothermal amplification for the detection of Sporisorium scitamineum in sugarcane.

    Science.gov (United States)

    Su, Yachun; Yang, Yuting; Peng, Qiong; Zhou, Dinggang; Chen, Yun; Wang, Zhuqing; Xu, Liping; Que, Youxiong

    2016-01-01

    Smut is a fungal disease with widespread prevalence in sugarcane planting areas. Early detection and proper identification of Sporisorium scitamineum are essential in smut management practices. In the present study, four specific primers targeting the core effector Pep1 gene of S. scitamineum were designed. Optimal concentrations of Mg(2+), primer and Bst DNA polymerase, the three important components of the loop-mediated isothermal amplification (LAMP) reaction system, were screened using a single factor experiment method and the L16(4(5)) orthogonal experimental design. Hence, a LAMP system suitable for detection of S. scitamineum was established. High specificity of the LAMP method was confirmed by the assay of S. scitamineum, Fusarium moniliforme, Pestalotia ginkgo, Helminthospcrium sacchari, Fusarium oxysporum and endophytes of Yacheng05-179 and ROC22. The sensitivity of the LAMP method was equal to that of the conventional PCR targeting Pep1 gene and was 100 times higher than that of the conventional PCR assay targeting bE gene in S. scitamineum. The results suggest that this novel LAMP system has strong specificity and high sensitivity. This method not only provides technological support for the epidemic monitoring of sugarcane smut, but also provides a good case for development of similar detection technology for other plant pathogens. PMID:27035751

  12. Annual meeting on nuclear technology '91. Technical session on 'Screen-aided man-machine dialogue for process control in nuclear power plant'

    International Nuclear Information System (INIS)

    The following topics were discussed in this session: Experience with fully computerized, screen-based control room operation in fossil-fuel power plant. Results of an evaluation of control room operation with CRT-based information display, and the resulting requirements for fully computerized control rooms in nuclear power plant. Simulator-based verification for 1400 MW PWR main control room. Concept and design of a fully computerized control room for future nuclear power plant. Requirements defined for fully computerized nuclear power plant control rooms from the licensing point of view. (orig./GL)

  13. Lunar Dust Mitigation Screens

    Science.gov (United States)

    Knutson, Shawn; Holloway, Nancy

    being developed in a collaborative effort between Langley Research Center and Kennedy Space Center. The screens typically consist of spiral shaped conductive traces patterned on high dielectric substrates (i.e. glass, quartz, polyimide film, etc.). Two broad categories of substrate materials are being investigated for the screens. One category consists of transparent substrates (i.e. glass, quartz, sapphire, etc.), and the other non-transparent sub-strates (Kapton, polyimide films, metals, etc.). The transparent screens utilize patterns made from indium tin oxide (ITO), a transparent conductive material, on clear substrates while the non-transparent screens use copper patterns on a transluscent or opaque substrates. Further, the screen is coated with a high dielectric polyimide cover layer to protect the screen pattern. One promising cover layer material that is currently being investigated is Langley Research Center-Soluble Imide (LaRC-SI), a NASA LaRC developed polyimide. Lastly, a top-coat of hard, inorganic material is evaporated onto the cover layer for protection from scratches due to abrasive nature of the dust. Of note, several top-coat materials are under investigation and include: aluminum oxide, silicon dioxide, titanium oxide, yttrium oxide, zirconium oxide, and zinc sulfide. The electrostatic dust mitigation screens function when a high voltage (700V or greater) is applied to the screen electrodes, thus creating an electromagnetic wave across the surface of the screen that repels the dust. Lunar dust typically contains a high positive charge; therefore, the screens are charged with a higher positive charge that effectively repels dust from the surface (i.e. like charges repel, unlike charges attract). It is anticipated that full development and maturation of this technology will enable humans to sustain a long term presence on the moon, and other planets where dust may have negative implications.

  14. Improved PCR Amplification of Broad Spectrum GC DNA Templates

    Science.gov (United States)

    Guido, Nicholas; Starostina, Elena; Leake, Devin; Saaem, Ishtiaq

    2016-01-01

    Many applications in molecular biology can benefit from improved PCR amplification of DNA segments containing a wide range of GC content. Conventional PCR amplification of DNA sequences with regions of GC less than 30%, or higher than 70%, is complex due to secondary structures that block the DNA polymerase as well as mispriming and mis-annealing of the DNA. This complexity will often generate incomplete or nonspecific products that hamper downstream applications. In this study, we address multiplexed PCR amplification of DNA segments containing a wide range of GC content. In order to mitigate amplification complications due to high or low GC regions, we tested a combination of different PCR cycling conditions and chemical additives. To assess the fate of specific oligonucleotide (oligo) species with varying GC content in a multiplexed PCR, we developed a novel method of sequence analysis. Here we show that subcycling during the amplification process significantly improved amplification of short template pools (~200 bp), particularly when the template contained a low percent of GC. Furthermore, the combination of subcycling and 7-deaza-dGTP achieved efficient amplification of short templates ranging from 10–90% GC composition. Moreover, we found that 7-deaza-dGTP improved the amplification of longer products (~1000 bp). These methods provide an updated approach for PCR amplification of DNA segments containing a broad range of GC content. PMID:27271574

  15. Brillouin amplification and processing of the Rayleigh scattered signal.

    Science.gov (United States)

    Mermelstein, David; Shacham, Eliashiv; Biton, Moran; Sternklar, Shmuel

    2015-07-15

    Brillouin amplification of Rayleigh scattering is demonstrated using two different configurations. In the first technique, the Rayleigh scattering and amplification occurs simultaneously in the same fiber. In the second technique, the amplification takes place in a second fiber. The differences between the two techniques are delineated. Using the second technique, we demonstrate single-sideband off-resonant Brillouin amplification of the Rayleigh signal. This technique is shown to enhance the SNR of a signal that is due to vibration-induced strain on the fiber. PMID:26176464

  16. Giant amplification of modes in parity-time symmetric waveguides

    International Nuclear Information System (INIS)

    The combination of the interference with the amplification of modes in a waveguide with gain and losses can result in a giant amplification of the propagating beam, which propagates without distortion of its average amplitude. An increase of the gain-loss gradient by only a few times results in a magnification of the beam by a several orders of magnitude. -- Highlights: ► We report giant beam amplification in parity-time symmetric optical waveguides. ► The amplification is due to interference of gain-guided modes. ► Flexible control both by parameters of the waveguide and of the input beam.

  17. Optimization of noncollinear optical parametric amplification

    Science.gov (United States)

    Schimpf, D. N.; Rothardt, J.; Limpert, J.; Tünnermann, A.

    2007-02-01

    Noncollinearly phase-matched optical parametric amplifiers (NOPAs) - pumped with the green light of a frequency doubled Yb-doped fiber-amplifier system 1, 2 - permit convenient generation of ultrashort pulses in the visible (VIS) and near infrared (NIR) 3. The broad bandwidth of the parametric gain via the noncollinear pump configuration allows amplification of few-cycle optical pulses when seeded with a spectrally flat, re-compressible signal. The short pulses tunable over a wide region in the visible permit transcend of frontiers in physics and lifescience. For instance, the resulting high temporal resolution is of significance for many spectroscopic techniques. Furthermore, the high magnitudes of the peak-powers of the produced pulses allow research in high-field physics. To understand the demands of noncollinear optical parametric amplification using a fiber pump source, it is important to investigate this configuration in detail 4. An analysis provides not only insight into the parametric process but also determines an optimal choice of experimental parameters for the objective. Here, the intention is to design a configuration which yields the shortest possible temporal pulse. As a consequence of this analysis, the experimental setup could be optimized. A number of aspects of optical parametric amplifier performance have been treated analytically and computationally 5, but these do not fully cover the situation under consideration here.

  18. Induction of gene amplification in Plasmodium falciparum

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, P.L.

    1985-01-01

    Human erythrocytic in vitro cultures of Honduras I strain of the malaria parasite Plasmodium falciparum have been stressed stepwise with increasing concentrations of methotrexate (MTX), a folate antagonist. This selection has produced a strain that is 450 times more resistant to the drug than the original culture. Uptake of sublethal doses of radiolabeled MTX by infected red blood cells was 6-36 times greater in the resistant cultures than in the nonresistant controls. DNA isolated from all of the parasites was probed by hybridization with /sup 35/S-labeled DNA derived from a clone of the yeast thymidylate synthetase (TS) gene. This showed 50 to 100 times more increased hybridization of the TS probe to the DNA from the resistant parasites is direct evidence of gene amplification because DHFR and TS are actually one and the same bifunctional enzyme in P. falciparum. Hence, the evidence presented indicates that induced resistance of the malaria parasite to MTX in this case is due to overproduction of DHFR resulting from amplification of the DHFR-TS gene.

  19. Induction of gene amplification in Plasmodium falciparum

    International Nuclear Information System (INIS)

    Human erythrocytic in vitro cultures of Honduras I strain of the malaria parasite Plasmodium falciparum have been stressed stepwise with increasing concentrations of methotrexate (MTX), a folate antagonist. This selection has produced a strain that is 450 times more resistant to the drug than the original culture. Uptake of sublethal doses of radiolabeled MTX by infected red blood cells was 6-36 times greater in the resistant cultures than in the nonresistant controls. DNA isolated from all of the parasites was probed by hybridization with 35S-labeled DNA derived from a clone of the yeast thymidylate synthetase (TS) gene. This showed 50 to 100 times more increased hybridization of the TS probe to the DNA from the resistant parasites is direct evidence of gene amplification because DHFR and TS are actually one and the same bifunctional enzyme in P. falciparum. Hence, the evidence presented indicates that induced resistance of the malaria parasite to MTX in this case is due to overproduction of DHFR resulting from amplification of the DHFR-TS gene

  20. Seismic Wave Amplification in 3D Alluvial Basins: 3D/1D Amplification Ratios from Fast Multipole BEM Simulations

    CERN Document Server

    Fajardo, Kristel C Meza; Chaillat, Stéphanie; Lenti, Luca

    2016-01-01

    In this work, we study seismic wave amplification in alluvial basins having 3D standard geometries through the Fast Multipole Boundary Element Method in the frequency domain. We investigate how much 3D amplification differs from the 1D (horizontal layering) case. Considering incident fields of plane harmonic waves, we examine the relationships between the amplification level and the most relevant physical parameters of the problem (impedance contrast, 3D aspect ratio, vertical and oblique incidence of plane waves). The FMBEM results show that the most important parameters for wave amplification are the impedance contrast and the so-called equivalent shape ratio. Using these two parameters, we derive simple rules to compute the fundamental frequency for various 3D basin shapes and the corresponding 3D/1D amplification factor for 5% damping. Effects on amplification due to 3D basin asymmetry are also studied and incorporated in the derived rules.

  1. Responsible implementation of expanded carrier screening.

    Science.gov (United States)

    Henneman, Lidewij; Borry, Pascal; Chokoshvili, Davit; Cornel, Martina C; van El, Carla G; Forzano, Francesca; Hall, Alison; Howard, Heidi C; Janssens, Sandra; Kayserili, Hülya; Lakeman, Phillis; Lucassen, Anneke; Metcalfe, Sylvia A; Vidmar, Lovro; de Wert, Guido; Dondorp, Wybo J; Peterlin, Borut

    2016-06-01

    This document of the European Society of Human Genetics contains recommendations regarding responsible implementation of expanded carrier screening. Carrier screening is defined here as the detection of carrier status of recessive diseases in couples or persons who do not have an a priori increased risk of being a carrier based on their or their partners' personal or family history. Expanded carrier screening offers carrier screening for multiple autosomal and X-linked recessive disorders, facilitated by new genetic testing technologies, and allows testing of individuals regardless of ancestry or geographic origin. Carrier screening aims to identify couples who have an increased risk of having an affected child in order to facilitate informed reproductive decision making. In previous decades, carrier screening was typically performed for one or few relatively common recessive disorders associated with significant morbidity, reduced life-expectancy and often because of a considerable higher carrier frequency in a specific population for certain diseases. New genetic testing technologies enable the expansion of screening to multiple conditions, genes or sequence variants. Expanded carrier screening panels that have been introduced to date have been advertised and offered to health care professionals and the public on a commercial basis. This document discusses the challenges that expanded carrier screening might pose in the context of the lessons learnt from decades of population-based carrier screening and in the context of existing screening criteria. It aims to contribute to the public and professional discussion and to arrive at better clinical and laboratory practice guidelines. PMID:26980105

  2. Rapid and Sensitive Detection of Shigella spp. and Salmonella spp. by Multiple Endonuclease Restriction Real-Time Loop-Mediated Isothermal Amplification Technique.

    Science.gov (United States)

    Wang, Yi; Wang, Yan; Luo, Lijuan; Liu, Dongxin; Luo, Xia; Xu, Yanmei; Hu, Shoukui; Niu, Lina; Xu, Jianguo; Ye, Changyun

    2015-01-01

    Shigella and Salmonella are frequently isolated from various food samples and can cause human gastroenteritis. Here, a novel multiple endonuclease restriction real-time loop-mediated isothermal amplification technology (MERT-LAMP) were successfully established and validated for simultaneous detection of Shigella strains and Salmonella strains in only a single reaction. Two sets of MERT-LAMP primers for 2 kinds of pathogens were designed from ipaH gene of Shigella spp. and invA gene of Salmonella spp., respectively. Under the constant condition at 63°C, the positive results were yielded in as short as 12 min with the genomic DNA extracted from the 19 Shigella strains and 14 Salmonella strains, and the target pathogens present in a sample could be simultaneously identified based on distinct fluorescence curves in real-time format. Accordingly, the multiplex detection assay significantly reduced effort, materials and reagents used, and amplification and differentiation were conducted at the same time, obviating the use of postdetection procedures. The analytical sensitivity of MERT-LAMP was found to be 62.5 and 125 fg DNA/reaction with genomic templates of Shigella strains and Salmonella strains, which was consist with normal LAMP assay, and at least 10- and 100-fold more sensitive than that of qPCR and conventional PCR approaches. The limit of detection of MERT-LAMP for Shigella strains and Salmonella strains detection in artificially contaminated milk samples was 5.8 and 6.4 CFU per vessel. In conclusion, the MERT-LAMP methodology described here demonstrated a potential and valuable means for simultaneous screening of Shigella and Salmonella in a wide variety of samples. PMID:26697000

  3. Evaluation and validation of a multi-residue method based on biochip technology for the simultaneous screening of six families of antibiotics in muscle and aquaculture products.

    Science.gov (United States)

    Gaudin, Valérie; Hedou, Celine; Soumet, Christophe; Verdon, Eric

    2016-03-01

    The Evidence Investigator™ system (Randox, UK) is a biochip and semi-automated system. The microarray kit II (AM II) is capable of detecting several compounds belonging to different families of antibiotics: quinolones, ceftiofur, thiamphenicol, streptomycin, tylosin and tetracyclines. The performance of this innovative system was evaluated for the detection of antibiotic residues in new matrices, in muscle of different animal species and in aquaculture products. The method was validated according to the European Decision No. EC/2002/657 and the European guideline for the validation of screening methods, which represents a complete initial validation. The false-positive rate was equal to 0% in muscle and in aquaculture products. The detection capabilities CCβ for 12 validated antibiotics (enrofloxacin, difloxacin, ceftiofur, desfuroyl ceftiofur cysteine disulfide, thiamphenicol, florfenicol, tylosin, tilmicosin, streptomycin, dihydrostreptomycin, tetracycline, doxycycline) were all lower than the respective maximum residue limits (MRLs) in muscle from different animal origins (bovine, ovine, porcine, poultry). No cross-reactions were observed with other antibiotics, neither with the six detected families nor with other families of antibiotics. The AM II kit could be applied to aquaculture products but with higher detection capabilities from those in muscle. The detection capabilities CCβ in aquaculture products were respectively at 0.25, 0.10 and 0.5 of the respective MRL in aquaculture products for enrofloxacin, tylosin and oxytetracycline. The performance of the AM II kit has been compared with other screening methods and with the performance characteristics previously determined in honey. PMID:26612266

  4. FRET based quantification and screening technology platform for the interactions of leukocyte function-associated antigen-1 (LFA-1 with intercellular adhesion molecule-1 (ICAM-1.

    Directory of Open Access Journals (Sweden)

    Sandeep Chakraborty

    Full Text Available The interaction between leukocyte function-associated antigen-1(LFA-1 and intercellular adhesion molecule-1 (ICAM-1 plays a pivotal role in cellular adhesion including the extravasation and inflammatory response of leukocytes, and also in the formation of immunological synapse. However, irregular expressions of LFA-1 or ICAM-1 or both may lead to autoimmune diseases, metastasis cancer, etc. Thus, the LFA-1/ICAM-1 interaction may serve as a potential therapeutic target for the treatment of these diseases. Here, we developed one simple 'in solution' steady state fluorescence resonance energy transfer (FRET technique to obtain the dissociation constant (Kd of the interaction between LFA-1 and ICAM-1. Moreover, we developed the assay into a screening platform to identify peptides and small molecules that inhibit the LFA-1/ICAM-1 interaction. For the FRET pair, we used Alexa Fluor 488-LFA-1 conjugate as donor and Alexa Fluor 555-human recombinant ICAM-1 (D1-D2-Fc as acceptor. From our quantitative FRET analysis, the Kd between LFA-1 and D1-D2-Fc was determined to be 17.93±1.34 nM. Both the Kd determination and screening assay were performed in a 96-well plate platform, providing the opportunity to develop it into a high-throughput assay. This is the first reported work which applies FRET based technique to determine Kd as well as classifying inhibitors of the LFA-1/ICAM-1 interaction.

  5. 78 FR 76860 - Contraband Screening for Criminal Justice Applications

    Science.gov (United States)

    2013-12-19

    ... for use by criminal justice and law enforcement for the detection of contraband. Screening technology is widely used by criminal justice practitioners (in particular, correctional facilities) to improve... of Justice Programs Contraband Screening for Criminal Justice Applications AGENCY: National...

  6. SHAPE EFFECT OF ANNULAR CONCENTRATOR IN ULTRASONIC SYSTEM ON AMPLIFICATION FACTOR OF VIBRATIONS AMPLITUDE

    Directory of Open Access Journals (Sweden)

    D. A. Stepanenko

    2016-01-01

    Full Text Available The paper contains a theoretical underpinning on creation of ultrasonic vibration concentrators based on annular elastic elements with non-circular (ellipse-like eccentric shape of internal contour. Shape of internal contour in polar coordinates is described by Fourier series relative to angular coordinate that consists of a constant term and first and second harmonics. An effect of geometric parameters of the concentrator on amplification factor and natural vibration frequencies has been investigated with the help of a finite element method. The paper reveals the possibility to control an amplification factor of annular concentrators while varying eccentricity of internal contour and mean value of cross-section thickness. The amplification factor satisfies a condition K < N, where N is thickness ratio of amplifier input and output sections, and it is decreasing with increase of vibration mode order. The similar condition has been satisfied for conical bar concentrator with the difference that in the case of bar concentrators an amplification is ensured due to variation of diameter and N will represent ratio of diameters. It has been proved that modification of internal contour shape makes it possible to carry out a wide-band tuning of natural frequencies of concentrator vibrations without alteration of its overall dimensions and substantial change of amplification factor, which is important for frequency matching of the concentrator and ultrasonic vibratory system. Advantages of the proposed concentrators include simplicity of design and manufacturing, small overall dimensions, possibility for natural frequency tuning by means of static load variation. The developed concentrators can find their application in ultrasonic devices and instruments for technological and medical purposes.

  7. An empirical approach for quantifying loop-mediated isothermal amplification (LAMP using Escherichia coli as a model system.

    Directory of Open Access Journals (Sweden)

    Sowmya Subramanian

    Full Text Available Loop mediated isothermal amplification (LAMP is a highly efficient, selective and rapid DNA amplification technique for genetic screening of pathogens. However, despite its popularity, there is yet no mathematical model to quantify the outcome and no well-defined metric for comparing results that are available. LAMP is intrinsically complex and involves multiple pathways for gene replication, making fundamental modelling nearly intractable. To circumvent this difficulty, an alternate, empirical model is introduced that will allow one to extract a set of parameters from the concentration versus time curves. A simple recipe to deduce the time to positive, Tp--a parameter analogous to the threshold cycling time in polymerase chain reaction (PCR, is also provided. These parameters can be regarded as objective and unambiguous indicators of LAMP amplification. The model is exemplified on Escherichia coli strains by using the two gene fragments responsible for vero-toxin (VT production and tested against VT-producing (O157 and O45 and non-VT producing (DH5 alpha strains. Selective amplification of appropriate target sequences was made using well established LAMP primers and protocols, and the concentrations of the amplicons were measured using a Qubit 2.0 fluorometer at specific intervals of time. The data is fitted to a generalized logistic function. Apart from providing precise screening indicators, representing the data with a small set of numbers offers significant advantages. It facilitates comparisons of LAMP reactions independently of the sampling technique. It also eliminates subjectivity in interpretation, simplifies data analysis, and allows easy data archival, retrieval and statistical analysis for large sample populations. To our knowledge this work represents a first attempt to quantitatively model LAMP and offer a standard method that could pave the way towards high throughput automated screening.

  8. Detection of Clostridium perfringens alpha toxin gene in lambs by loop mediated isothermal amplification

    Directory of Open Access Journals (Sweden)

    B. Radhika

    2016-01-01

    Full Text Available Aim: The loop mediated isothermal amplification (LAMP was standardized for rapid detection of Clostridium perfringens. Materials and Methods: A total of 120 fecal samples were collected from enterotoxemia suspected lambs were used for screening of C. perfringens cpa gene by LAMP. The specificity of the LAMP amplified products was tested by digesting with restriction enzyme XmnI for alpha toxin gene. Results: Out of 120 samples screened 112 (93.3% samples were positive by both LAMP and polymerase chain reaction (PCR for detection of cpa gene which indicated the equal sensitivity of both the tests. The enzyme produced single cut in 162 base pair amplified product of alpha toxin gene at 81 base pair resulting in a single band in gel electrophoresis. Conclusion: Both LAMP and PCR for detection of cpa gene indicated the equal sensitivity of both the tests. Standardization of LAMP reaction for amplification of epsilon and beta toxin genes will help to identify the C. perfringens toxin types from the clinical samples. The test could be a suitable alternative to the PCR in detection of toxin types without the help of sophisticated machinery like thermal cycler. Considering its simplicity in operation and high sensitivity, there is the potential use of this technique in clinical diagnosis and surveillance of infectious diseases.

  9. Frequent amplification of CENPF, GMNN and CDK13 genes in hepatocellular carcinomas.

    Directory of Open Access Journals (Sweden)

    Hye-Eun Kim

    Full Text Available Genomic changes frequently occur in cancer cells during tumorigenesis from normal cells. Using the Illumina Human NS-12 single-nucleotide polymorphism (SNP chip to screen for gene copy number changes in primary hepatocellular carcinomas (HCCs, we initially detected amplification of 35 genes from four genomic regions (1q21-41, 6p21.2-24.1, 7p13 and 8q13-23. By integrated screening of these genes for both DNA copy number and gene expression in HCC and colorectal cancer, we selected CENPF (centromere protein F/mitosin, GMNN (geminin, DNA replication inhibitor, CDK13 (cyclin-dependent kinase 13, and FAM82B (family with sequence similarity 82, member B as common cancer genes. Each gene exhibited an amplification frequency of ~30% (range, 20-50% in primary HCC (n = 57 and colorectal cancer (n = 12, as well as in a panel of human cancer cell lines (n = 70. Clonogenic and invasion assays of NIH3T3 cells transfected with each of the four amplified genes showed that CENPF, GMNN, and CDK13 were highly oncogenic whereas FAM82B was not. Interestingly, the oncogenic activity of these genes (excluding FAM82B was highly correlated with gene-copy numbers in tumor samples (correlation coefficient, r>0.423, indicating that amplifications of CENPF, GMNN, and CDK13 genes are tightly linked and coincident in tumors. Furthermore, we confirmed that CDK13 gene copy number was significantly associated with clinical onset age in patients with HCC (P = 0.0037. Taken together, our results suggest that coincidently amplified CDK13, GMNN, and CENPF genes can play a role as common cancer-driver genes in human cancers.

  10. Third-generation femtosecond technology

    OpenAIRE

    Fattahi, Hanieh

    2015-01-01

    Chirped pulse amplification in solid-state lasers is currently the method of choice for producing high-energy ultrashort pulses, having surpassed the performance of dye lasers over 20 years ago. The third generation of femtosecond technology based on short-pulse-pumped optical parametric chirped pulse amplification (OPCPA) holds promise for providing few-cycle pulses with terawatt-scale peak powers and kilowatt-scale-average powers simultaneously, heralding the next wave of ...

  11. Broadening and Amplification of an Infrared Femtosecond Pulse for Optical Parametric Chirped-Pulse Amplification

    Institute of Scientific and Technical Information of China (English)

    WANG He-Lin; YANG Ai-Jun; LENG Yu-Xin

    2011-01-01

    A high-average-power diode-pumped narrowband regenerative chirped pulse amplifier is developed using the thin-rod Nd:YAG laser architecture for optical parametric chirped-pulse amplification (OPCPA).The effect of the etalons on the amplified pulse in the regenerative cavity is studied experimentally and theoretically.By inserting glass etalons of thickness 1 mm and 5 mm into the regenerative cavity,the pre-stretching pulse from an (O)ffner stretcher is further broadened to above 200ps,which matches the amplification windows of the signal pulses in OPCPA and is suitable for use as a pump source in the OPCPA system.The bandwidth of the amplified pulse is 1.5 nm,and an output energy of 2mJ is achieved at a repetition rate of 10 Hz.Optical parametric chirped pulse amplification (OPCPA)[1-4] has attracted a great deal of attention as the most promising technique for generating ultrashort ultrahigh-peak-power laser pulses because of its very broad gain bandwidth,negligible thermal load on the nonlinear crystal,and extremely high singlepass gain as compared to amplifiers based on laser gain media.For efficient amplification and high fidelity of dispersion compensation in OPCPA,a femtosecond seed pulse is first stretched to several tens of picoseconds with a bulk grating stretcher or a fiber stretcher.%A high-average-power diode-pumped narrowband regenerative chirped pulse amplifier is developed using the thin-rod Nd:YAG laser architecture for optical parametric chirped-pulse amplification (OPCPA). The effect of the etalons on the amplified pulse in the regenerative cavity is studied experimentally and theoretically. By inserting glass etalons of thickness 1 mm and 5 mm into the regenerative cavity, the pre-stretching pulse from an (O)finer stretcher is further broadened to above 200 ps, which matches the amplification windows of the signal pulses in OPCPA and is suitable for use as a pump source in the OPCPA system. The bandwidth of the amplified pulse is 1.5 nm, and an

  12. A Sign Language Screen Reader for Deaf

    Science.gov (United States)

    El Ghoul, Oussama; Jemni, Mohamed

    Screen reader technology has appeared first to allow blind and people with reading difficulties to use computer and to access to the digital information. Until now, this technology is exploited mainly to help blind community. During our work with deaf people, we noticed that a screen reader can facilitate the manipulation of computers and the reading of textual information. In this paper, we propose a novel screen reader dedicated to deaf. The output of the reader is a visual translation of the text to sign language. The screen reader is composed by two essential modules: the first one is designed to capture the activities of users (mouse and keyboard events). For this purpose, we adopted Microsoft MSAA application programming interfaces. The second module, which is in classical screen readers a text to speech engine (TTS), is replaced by a novel text to sign (TTSign) engine. This module converts text into sign language animation based on avatar technology.

  13. Next-generation phenotypic screening.

    Science.gov (United States)

    Warchal, Scott J; Unciti-Broceta, Asier; Carragher, Neil O

    2016-07-01

    Phenotypic drug discovery (PDD) strategies are defined by screening and selection of hit or lead compounds based on quantifiable phenotypic endpoints without prior knowledge of the drug target. We outline the challenges associated with traditional phenotypic screening strategies and propose solutions and new opportunities to be gained by adopting modern PDD technologies. We highlight both historical and recent examples of approved drugs and new drug candidates discovered by modern phenotypic screening. Finally, we offer a prospective view of a new era of PDD underpinned by a wealth of technology advances in the areas of in vitro model development, high-content imaging and image informatics, mechanism-of-action profiling and target deconvolution. PMID:27357617

  14. A lab-on-a-chip system with integrated sample preparation and loop-mediated isothermal amplification for rapid and quantitative detection of Salmonella spp. in food samples

    DEFF Research Database (Denmark)

    Sun, Yi; Than Linh, Quyen; Hung, Tran Quang;

    2015-01-01

    Foodborne disease is a major public health threat worldwide. Salmonellosis, an infectious disease caused by Salmonella spp., is one of the most common foodborne diseases. Isolation and identification of Salmonella by conventional bacterial culture or molecular-based methods are time consuming and...... amplification (LAMP) for rapid and quantitative detection of Salmonella spp. in food samples. The whole diagnostic procedures including DNA isolation, isothermal amplification, and real-time detection were accomplished in a single chamber. Up to eight samples could be handled simultaneously and the system was...... on-site screening of Salmonella for applications in food safety control, environmental surveillance, and clinical diagnostics....

  15. A comparison of single molecule and amplification based sequencing of cancer transcriptomes.

    Directory of Open Access Journals (Sweden)

    Lee T Sam

    Full Text Available The second wave of next generation sequencing technologies, referred to as single-molecule sequencing (SMS, carries the promise of profiling samples directly without employing polymerase chain reaction steps used by amplification-based sequencing (AS methods. To examine the merits of both technologies, we examine mRNA sequencing results from single-molecule and amplification-based sequencing in a set of human cancer cell lines and tissues. We observe a characteristic coverage bias towards high abundance transcripts in amplification-based sequencing. A larger fraction of AS reads cover highly expressed genes, such as those associated with translational processes and housekeeping genes, resulting in relatively lower coverage of genes at low and mid-level abundance. In contrast, the coverage of high abundance transcripts plateaus off using SMS. Consequently, SMS is able to sequence lower- abundance transcripts more thoroughly, including some that are undetected by AS methods; however, these include many more mapping artifacts. A better understanding of the technical and analytical factors introducing platform specific biases in high throughput transcriptome sequencing applications will be critical in cross platform meta-analytic studies.

  16. Beyond the diffraction limit via optical amplification

    CERN Document Server

    Kellerer, Aglae N

    2016-01-01

    In a previous article we suggested a method to overcome the diffraction limit behind a telescope. We refer to theory and recent numerical simulations, and test whether it is indeed possible to use photon amplification to enhance the angular resolution of a telescope or a microscope beyond the diffraction limit. An essential addition is the proposal to select events with above-average ratio of stimulated to spontaneous photons. We find that the diffraction limit of a telescope is surpassed by a factor ten for an amplifier gain of 200, if the analysis is restricted to a tenth of the incoming astronomical photons. A gain of 70 is sufficient with a hundredth of the photons.

  17. Amplification sans bruit d'images optiques

    Science.gov (United States)

    Gigan, S.; Delaubert, V.; Lopez, L.; Treps, N.; Maitre, A.; Fabre, C.

    2004-11-01

    Nous utilisons un Oscillateur Paramétrique Optique (OPO) pompé sous le seuil dans le but d'amplifier une image multimode transverse sans dégradation du rapport signal à bruit. Le dispositif expérimental met en œuvre un OPO de type II triplement résonant et semi-confocal pour le faisceau amplifié. L'existence d'effets quantiques lors de l'amplification multimode dans un tel dispositif a été montrée expérimentalement. Plus généralement, ceci nous a amené à étudier les propriétés quantiques transverses des faisceaux lumineux amplifiés. Une telle étude peut trouver des applications non seulement en imagerie, mais également dans le traitement quantique de l'information.

  18. Entanglement amplification via local weak measurements

    International Nuclear Information System (INIS)

    We propose a measurement-based method to produce a maximally-entangled state from a partially-entangled pure state. Our goal can be thought of as entanglement distillation from a single copy of a partially-entangled state. The present approach involves local two-outcome weak measurements. We show that the application of these local weak measurements leads to a probabilistic amplification of entanglement. In addition, we examine how the probability to find the maximally-entangled state is related to the entanglement of the input state. We also study the application of our method to a mixed initial state. We show that the protocol is successful if the separable part of the mixed initial state fulfils certain conditions. (paper)

  19. Chirped pulse amplification: Present and future

    International Nuclear Information System (INIS)

    Short pulses with ultrahigh peak powers have been generated in Nd: glass and Alexandrite using the Chirped Pulse Amplification (CPA) technique. This technique has been successful in producing picosecond terawatt pulses with a table-top laser system. In the near future, CPA will be applied to large laser systems such as NOVA to produce petawatt pulses (1 kJ in a 1 ps pulse) with focused intensities exceeding 10/sup /plus/21/ W/cm2. These pulses will be associated with electric fields in excess of 100 e/a/sub o/2 and blackbody energy densities equivalent to 3 /times/ 1010 J/cm3. This petawatt source will have important applications in x-ray laser research and will lead to fundamentally new experiments in atomic, nuclear, solid-state, plasma, and high-energy density physics. A review of present and future designs are discussed. 17 refs., 5 figs

  20. Integrated Amplification Microarrays for Infectious Disease Diagnostics

    Directory of Open Access Journals (Sweden)

    Darrell P. Chandler

    2012-11-01

    Full Text Available This overview describes microarray-based tests that combine solution-phase amplification chemistry and microarray hybridization within a single microfluidic chamber. The integrated biochemical approach improves microarray workflow for diagnostic applications by reducing the number of steps and minimizing the potential for sample or amplicon cross-contamination. Examples described herein illustrate a basic, integrated approach for DNA and RNA genomes, and a simple consumable architecture for incorporating wash steps while retaining an entirely closed system. It is anticipated that integrated microarray biochemistry will provide an opportunity to significantly reduce the complexity and cost of microarray consumables, equipment, and workflow, which in turn will enable a broader spectrum of users to exploit the intrinsic multiplexing power of microarrays for infectious disease diagnostics.

  1. Explanatory Model for Sound Amplification in a Stethoscope

    Science.gov (United States)

    Eshach, H.; Volfson, A.

    2015-01-01

    In the present paper we suggest an original physical explanatory model that explains the mechanism of the sound amplification process in a stethoscope. We discuss the amplification of a single pulse, a continuous wave of certain frequency, and finally we address the resonant frequencies. It is our belief that this model may provide students with…

  2. Parametric Amplification of Vacuum Fluctuations in a Spinor Condensate

    DEFF Research Database (Denmark)

    Klempt, C.; Topic, O.; Gebreyesus, G.;

    2010-01-01

    Parametric amplification of vacuum fluctuations is crucial in modern quantum optics, enabling the creation of squeezing and entanglement. We demonstrate the parametric amplification of vacuum fluctuations for matter waves using a spinor F=2 87Rb condensate. Interatomic interactions lead to correl...

  3. Short-Pulse Amplification by Strongly-Coupled Brillouin Scattering

    CERN Document Server

    Edwards, Matthew R; Mikhailova, Julia M; Fisch, Nathaniel J

    2016-01-01

    We examine the feasibility of strongly-coupled stimulated Brillouin scattering as a mechanism for the plasma-based amplification of sub-picosecond pulses. In particular, we use fluid theory and particle-in-cell simulations to compare the relative advantages of Raman and Brillouin amplification over a broad range of achievable parameters.

  4. The Quantum Theory of Optical Parametric Amplification

    Science.gov (United States)

    Hussain, N. A.

    Available from UMI in association with The British Library. Requires signed TDF. The aim of this thesis is to investigate the effect of parametric amplification on various forms of light. In particular we shall consider number and coherent states, but many of the calculations hold for those states whose operators satisfy the properties, = = ==0 e.g. chaotic light. The first chapter lays down the fundamental preliminaries necessary for our calculations and reviews linear amplifier theory. We consider the phase sensitive and insensitive forms of amplifiers modelling the former on the degenerate parametric amplifier and the latter on the non-degenerate and inverted population amplifiers. Chapter 2 deals with balanced homodyne detection of a narrow band coherent state before and after degenerate parametric amplification. In chapter 3 we consider a continuous mode number state produced by atomic emission and parametrically amplified using the formalism of Collett and Gardiner. We give general results for the output flux intensity and also consider the simpler case where the atomic decay rate is much smaller than the parametric cavity decay rate. Also we consider the degree of second order coherence using this simplified theory. Chapters 4 and 5 consider the double amplifier interferometer, using single and continuous mode theories, and enable us to determine the form of amplifier which produces the best visibility and hence lowest noise figures. The travelling-wave parametric amplifier is discussed in chapter 6 and is contrasted with the cavity parametric amplifier discussed in chapters 1 and 2. Finally we consider the much contemplated idea of using amplifiers to boost signals in fibre optic transmission lines using our model of the parametric amplifier and examining the degradation of the signal-to-noise ratio. We consider both coherent and squeezed inputs and our results hold for both cavity and travelling -wave amplifiers.

  5. The Place of the Classroom and the Space of the Screen: Relational Pedagogy and Internet Technology. New Literacies and Digital Epistemologies, Volume 50

    Science.gov (United States)

    Friesen, Norm

    2011-01-01

    This book examines how common e-learning technologies open up compelling, if limited, experiential spaces for users, similar to the imaginary worlds opened up by works of fiction. However, these experiential worlds are markedly different from the "real" world of physical objects and embodied relations. This book shows these differences to be of…

  6. Cross-species amplification of microsatellite markers in Mycteria leucocephala Pennant 1769: molted feathers as successful DNA source.

    Science.gov (United States)

    Sharma, Bharat Bhushan; Mustafa, Mohd; Sharma, Tusha; Banerjee, Basu Dev; Urfi, Abdul Jamil

    2014-10-01

    DNA from molted feathers is being increasingly used for genetic studies on birds. However, the DNA obtained from such non-invasive sources is often not of enough quantity and quality for isolation of new microsatellite markers. The present study examined the potential of shed feathers of near threatened Painted Stork as a source of its DNA for cross-species amplification of microsatellites. Thirty-one shed feathers of varying conditions ('good' and 'deteriorated') and sizes ('large', 'intermediate' and 'small') collected in a north Indian population were used to isolate DNA by a standard isopropanol method and 11 microsatellite markers already developed in the Wood Stork were screened for amplification. Nine plucked feathers from two dead Painted Storks were also used to compare the DNA yield and amplification success. The DNA yield of feathers varied significantly in relation to the calamus size and condition. Among molted feathers, 'good' and 'large' samples provided more DNA than 'deteriorated' and 'small' ones, respectively. 'Large' plucked feathers yielded more DNA than 'large' molted feathers. DNA was almost degraded in all the samples and ratio of absorbance at 260/280 nm varied from 1.0 to 1.8, indicating impurity in many samples. Independent of DNA yields, all microsatellites were cross-amplified in all kinds of feathers, with > 80% success in different feather categories. It is concluded that the shed feathers can be successfully used to isolate DNA in the Painted Stork and for cross-species amplification of microsatellites. PMID:25345251

  7. Preparation and Amplification of Colony of Goat Transgenic Fetal Fibroblast and Mammary Gland Epithelial Cell with Human Lactoferrin Gene

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yu-ling; LIU Feng-jun; ZHANG Yong

    2009-01-01

    [Objective] The aim was to explore technical system of making single transgenic positive cells become colony cells by amplification culture. [Method] Fetal fibroblasts and mammary gland epithelial cells of single goat fetus of pBLM-C1 which specifically expressed human lactoferrin were cloned. Single cell colony of single transfection cell was prepared with 3 concentrations of 0%, 50% and 100% conditioned culture media. Transfection cell and non-transfection cell were carried out amplification culture by con-culture, neo gene was as screened gene, genome DNA of transfection cell was detected by PCR method. Chromosome karyotype analysis of single colony cell was tested. [Result] Compared with non-conditioned culture medium, 100% conditioned culture medium could greatly increase survived rate of single colony cells (FF: 53.33% vs. 10.00%; MGE: 33.33% vs. 6.67%). Compared with control, con-culture of transfection cell and non-transfection cell could greatly increase rate of transfection cell single colony after amplification culture (FF: 53.33% vs. 10.00%;MGE: 33.33% vs. 6.67%), confluence time of amplification culture was significantly decreased (20-30 d). The result of PCR showed that the colony cell obtained by above method contained hLF target gene. The result of karyotype analysis showed that most cloned cell chromosomes were normal. [Conclusion] The study provides a reliable method for separating transgenic cell, inserting and diagnosing ideal vector, and can save expense and time for transgenic animal production.

  8. Designing Online Courses for Screen Reader Users

    Science.gov (United States)

    Kearns, Lorna R.; Frey, Barbara A.; McMorland, Gabriel

    2013-01-01

    A review of multiple online courses at one institution was conducted by a skilled screen reader user for the purpose of assessing the extent to which the courses were navigable and understandable to online students using assistive technologies. This paper identifies features of online courses that may present problems for screen reader users and…

  9. Ultrabright multikilovolt x-ray source: saturated amplification on noble gas transition arrays from hollow atom states

    Science.gov (United States)

    Rhodes, Charles K.; Boyer, Keith

    2004-02-17

    An apparatus and method for the generation of ultrabright multikilovolt x-rays from saturated amplification on noble gas transition arrays from hollow atom states is described. Conditions for x-ray amplification in this spectral region combine the production of cold, high-Z matter, with the direct, selective multiphoton excitation of hollow atoms from clusters using ultraviolet radiation and a nonlinear mode of confined, self-channeled propagation in plasmas. Data obtained is consistent with the presence of saturated amplification on several transition arrays of the hollow atom Xe(L) spectrum (.lambda..about.2.9 .ANG.). An estimate of the peak brightness achieved is .about.10.sup.29 .gamma..multidot.s.sup.-1.multidot.mm.sup.-2.multidot.mr.sup.-2 (0.1% Bandwidth).sup.-1, that is .about.10.sup.5 -fold higher than presently available synchotron technology.

  10. 基于PLC、变频器和触摸屏技术的温室大棚控制系统设计%Greenhouse system design based on PLC, Inverter and Touch screen technology

    Institute of Scientific and Technical Information of China (English)

    狄敬国; 李秀美

    2012-01-01

      提出了一种新型智能化的温室控制的方法,充分利用PLC技术、变频器技术和触摸屏技术,实现了对温室大棚内温度、湿度、光照等参数的控制,设计人机界面,操作控制方便,达到了控制效果明显,工作可靠稳定,环保节能的目的。实践证明,该设计能够实现温室的自动控制,提高温室管理水平。%  This paper proposes a new intelligent control method greenhouse full use of PLC technology, in-verter technology and touch screen technology, on the greenhouse temperature, humidity, light and other pa-rameters of the control, design human-machine interface, convenient control to achieve the control effect is obvious, reliable and stable, environmentally friendly energy saving purposes. Practice has proved that the design can achieve automatic control of the greenhouse, increased greenhouse management.

  11. Study on high gain broadband optical parametric chirped pulse amplification

    International Nuclear Information System (INIS)

    Optical parametric chirped pulse amplification has apparent advantages over the current schemes for high energy ultrashort pulse amplification. High gain in a single pass amplification, small B-integral, low heat deposition, high contrast ratio and, especially the extremely broad gain bandwidth with large-size crystals available bring people new hope for over multi-PW level at which the existing Nd:glass systems suffered difficulties. In this paper we present simulation and experimental studies for a high gain optical parametric chirped pulse amplification system which may be used as a preamplifier to replace the current complicated regenerative system or multi-pass Ti:sapphire amplifiers. Investigations on the amplification bandwidth and gain with BBO are performed. Analysis and discussions are also given. (author)

  12. Progress of monoclonal antibody secretion hybridoma cell rapid screening technology based on HTS-ELISA%基于HTS-ELISA的单克隆抗体分泌杂交瘤细胞筛选技术进展

    Institute of Scientific and Technical Information of China (English)

    甄玉萍; 裴世春; 高建伟

    2014-01-01

    Various immune analysis technologies based on the monoclonal antibody are the main develop-ment direction for modern food safety rapid detection technology. Therefore, preparation of monoclonal anti-bodies with high-activity has got more and more attention by researchers. Preparation of monoclonal antibody usually involves many techniques, including the preparation of the antigen, immune design, cell fusion, screening of active hybridoma and antibody purification. Among them, the screening of monoclonal antibody secreting hybridoma cells is a key of the prepared monoclonal antibody part. Therefore, in order to provide a reference for high-activity monoclonal antibody preparation and the development of rapid detection technology for food safety, this paper focused on low density fusion cell culture, special equipment and the principle and technology of determining hybridoma cell activity in the screening process according to drag the number of holes (Trailing) to related activities, and mainly introduced one kind of high-activity monoclonal antibody se-cretion hybridoma technique which was based on HTS-ELISA screening method.%基于单克隆抗体的各类免疫分析技术是现代食品安全快速检测技术发展的主要方向之一,因此,高活性单克隆抗体的制备方法自然为众多研究者所关注。通常单克隆抗体的制备过程涉及到很多技术环节,包括抗原制备、免疫剂量设计、细胞融合、活性杂交瘤细胞筛选以及抗体纯化等,其中分泌单克隆抗体杂交瘤细胞的筛选环节是单克隆抗体制备的关键一环。为此,本文主要介绍了一种基于HTS-ELISA的高活性单克隆抗体分泌杂交瘤细胞的筛选技术,重点是对融合细胞的低密度培养、特殊仪器设备和在筛选过程中如何依据拖孔数(Trailing)来判断杂交瘤细胞的活性等相关的原理和技术,旨在为我国高活性单克隆抗体制备技术的发展及加快食品安全快

  13. Clinical application of somatosensory amplification in psychosomatic medicine

    Directory of Open Access Journals (Sweden)

    Nakao Mutsuhiro

    2007-10-01

    Full Text Available Abstract Many patients with somatoform disorders are frequently encountered in psychosomatic clinics as well as in primary care clinics. To assess such patients objectively, the concept of somatosensory amplification may be useful. Somatosensory amplification refers to the tendency to experience a somatic sensation as intense, noxious, and disturbing. It may have a role in a variety of medical conditions characterized by somatic symptoms that are disproportionate to demonstrable organ pathology. It may also explain some of the variability in somatic symptomatology found among different patients with the same serious medical disorder. It has been assessed with a self-report questionnaire, the Somatosensory Amplification Scale. This instrument was developed in a clinical setting in the U.S., and the reliability and validity of the Japanese and Turkish versions have been confirmed as well. Many studies have attempted to clarify the specific role of somatosensory amplification as a pathogenic mechanism in somatization. It has been reported that somatosensory amplification does not correlate with heightened sensitivity to bodily sensations and that emotional reactivity exerts its influence on somatization via a negatively biased reporting style. According to our recent electroencephalographic study, somatosensory amplification appears to reflect some aspects of long-latency cognitive processing rather than short-latency interoceptive sensitivity. The concept of somatosensory amplification can be useful as an indicator of somatization in the therapy of a broad range of disorders, from impaired self-awareness to various psychiatric disorders. It also provides useful information for choosing appropriate pharmacological or psychological therapy. While somatosensory amplification has a role in the presentation of somatic symptoms, it is closely associated with other factors, namely, anxiety, depression, and alexithymia that may also influence the same

  14. Practices of efficient high frequency dewatering screen technology in dry discharge of tailings%高效高频脱水筛在尾矿干排处理中的应用实践

    Institute of Scientific and Technical Information of China (English)

    李永亭; 张云龙

    2016-01-01

    The paper sets forth the feasibility of the application of efficient high frequency dewatering screen in dry discharge of tailings , and it has been successfully applied in one gold mine and obtained a dry tailings pile of which the water content is less than 15%.The paper introduces in detail the technical flowsheet and production index of this processing technology in the gold mine ,comprehensively analyzes the running cost and economic benefits of the dewatering screen .Practices prove that this technology requires low investment and low running cost ,renders high wa-ter recovery and prominent benefits ,and it can recover cyanide to the utmost .%阐述了采用高效高频脱水筛处理尾矿的可行性,并在某金矿的尾矿处理中得到了成功应用,最终可得到含水量小于15%的干堆尾矿.该文详细介绍了高效高频脱水筛处理某金矿尾矿的工艺流程和生产指标,且对其运行成本和经济效益进行了综合分析.实践证明,该尾矿处理工艺节省了投资费用,降低了运行成本,提高了回水率,经济效益显著,并可以最大限度地回收利用尾矿废水中的氰化物.

  15. Mobile Screens: The Visual Regime of Navigation

    OpenAIRE

    Verhoeff, N.

    2012-01-01

    In this book on screen media, space, and mobility I compare synchronically, as well as diachronically, diverse and variegated screen media - their technologies and practices – as sites for virtual mobility and navigation. Mobility as a central trope can be found on the multiple levels that are investigated. First, the representation of mobility in audiovisual media is concerned with the virtual mobility of media technology in general, and of the change in their possibilities. I analyze the wa...

  16. Screen time and children

    Science.gov (United States)

    "Screen time" is a term used for activities done in front of a screen, such as watching TV, working on a computer, or playing video games. Screen time is sedentary activity, meaning you are being physically ...

  17. Lung Cancer Screening

    Science.gov (United States)

    ... Treatment Lung Cancer Prevention Lung Cancer Screening Research Lung Cancer Screening (PDQ®)–Patient Version What is screening? Go ... These are called diagnostic tests . General Information About Lung Cancer Key Points Lung cancer is a disease in ...

  18. What Is Carrier Screening?

    Science.gov (United States)

    ... you want to learn. Search form Search Carrier screening You are here Home Testing & Services Testing for ... help you make the decision. What Is Carrier Screening? Carrier screening checks if a person is a " ...

  19. Skin Cancer Screening

    Science.gov (United States)

    ... Genetics of Skin Cancer Skin Cancer Screening Research Skin Cancer Screening (PDQ®)–Patient Version What is screening? Go ... These are called diagnostic tests . General Information About Skin Cancer Key Points Skin cancer is a disease in ...

  20. Cascaded parametric amplification for highly efficient terahertz generation.

    Science.gov (United States)

    Ravi, Koustuban; Hemmer, Michael; Cirmi, Giovanni; Reichert, Fabian; Schimpf, Damian N; Mücke, Oliver D; Kärtner, Franz X

    2016-08-15

    A highly efficient, practical approach to high-energy multi-cycle terahertz (THz) generation based on spectrally cascaded optical parametric amplification (THz-COPA) is introduced. Feasible designs are presented that enable the THz wave, initially generated by difference frequency generation between a narrowband optical pump and optical seed (0.1-10% of pump energy), to self-start a cascaded (or repeated) energy downconversion of pump photons in a single pass through a single crystal. In cryogenically cooled, periodically poled lithium niobate, unprecedented energy conversion efficiencies >8% achievable with existing pump laser technology are predicted using realistic simulations. The calculations account for cascading effects, absorption, dispersion, and laser-induced damage. Due to the simultaneous, coupled nonlinear evolution of multiple phase-matched three-wave mixing processes, THz-COPA exhibits physics distinctly different from conventional three-wave mixing parametric amplifiers. This, in turn, governs optimal phase-matching conditions, evolution of optical spectra, and limitations of the nonlinear process. Circumventing these limitations is shown to yield conversion efficiencies ≫10%. PMID:27519094

  1. Market screening of natural gas reformers

    International Nuclear Information System (INIS)

    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)

  2. Mechanism of Gene Amplification via Yeast Autonomously Replicating Sequences

    Directory of Open Access Journals (Sweden)

    Shelly Sehgal

    2015-01-01

    Full Text Available The present investigation was aimed at understanding the molecular mechanism of gene amplification. Interplay of fragile sites in promoting gene amplification was also elucidated. The amplification promoting sequences were chosen from the Saccharomyces cerevisiae ARS, 5S rRNA regions of Plantago ovata and P. lagopus, proposed sites of replication pausing at Ste20 gene locus of S. cerevisiae, and the bend DNA sequences within fragile site FRA11A in humans. The gene amplification assays showed that plasmid bearing APS from yeast and human beings led to enhanced protein concentration as compared to the wild type. Both the in silico and in vitro analyses were pointed out at the strong bending potential of these APS. In addition, high mitotic stability and presence of TTTT repeats and SAR amongst these sequences encourage gene amplification. Phylogenetic analysis of S. cerevisiae ARS was also conducted. The combinatorial power of different aspects of APS analyzed in the present investigation was harnessed to reach a consensus about the factors which stimulate gene expression, in presence of these sequences. It was concluded that the mechanism of gene amplification was that AT rich tracts present in fragile sites of yeast serve as binding sites for MAR/SAR and DNA unwinding elements. The DNA protein interactions necessary for ORC activation are facilitated by DNA bending. These specific bindings at ORC promote repeated rounds of DNA replication leading to gene amplification.

  3. Mechanism of gene amplification via yeast autonomously replicating sequences.

    Science.gov (United States)

    Sehgal, Shelly; Kaul, Sanjana; Dhar, M K

    2015-01-01

    The present investigation was aimed at understanding the molecular mechanism of gene amplification. Interplay of fragile sites in promoting gene amplification was also elucidated. The amplification promoting sequences were chosen from the Saccharomyces cerevisiae ARS, 5S rRNA regions of Plantago ovata and P. lagopus, proposed sites of replication pausing at Ste20 gene locus of S. cerevisiae, and the bend DNA sequences within fragile site FRA11A in humans. The gene amplification assays showed that plasmid bearing APS from yeast and human beings led to enhanced protein concentration as compared to the wild type. Both the in silico and in vitro analyses were pointed out at the strong bending potential of these APS. In addition, high mitotic stability and presence of TTTT repeats and SAR amongst these sequences encourage gene amplification. Phylogenetic analysis of S. cerevisiae ARS was also conducted. The combinatorial power of different aspects of APS analyzed in the present investigation was harnessed to reach a consensus about the factors which stimulate gene expression, in presence of these sequences. It was concluded that the mechanism of gene amplification was that AT rich tracts present in fragile sites of yeast serve as binding sites for MAR/SAR and DNA unwinding elements. The DNA protein interactions necessary for ORC activation are facilitated by DNA bending. These specific bindings at ORC promote repeated rounds of DNA replication leading to gene amplification. PMID:25685838

  4. A mechanism of gene amplification driven by small DNA fragments.

    Directory of Open Access Journals (Sweden)

    Kuntal Mukherjee

    Full Text Available DNA amplification is a molecular process that increases the copy number of a chromosomal tract and often causes elevated expression of the amplified gene(s. Although gene amplification is frequently observed in cancer and other degenerative disorders, the molecular mechanisms involved in the process of DNA copy number increase remain largely unknown. We hypothesized that small DNA fragments could be the trigger of DNA amplification events. Following our findings that small fragments of DNA in the form of DNA oligonucleotides can be highly recombinogenic, we have developed a system in the yeast Saccharomyces cerevisiae to capture events of chromosomal DNA amplification initiated by small DNA fragments. Here we demonstrate that small DNAs can amplify a chromosomal region, generating either tandem duplications or acentric extrachromosomal DNA circles. Small fragment-driven DNA amplification (SFDA occurs with a frequency that increases with the length of homology between the small DNAs and the target chromosomal regions. SFDA events are triggered even by small single-stranded molecules with as little as 20-nt homology with the genomic target. A double-strand break (DSB external to the chromosomal amplicon region stimulates the amplification event up to a factor of 20 and favors formation of extrachromosomal circles. SFDA is dependent on Rad52 and Rad59, partially dependent on Rad1, Rad10, and Pol32, and independent of Rad51, suggesting a single-strand annealing mechanism. Our results reveal a novel molecular model for gene amplification, in which small DNA fragments drive DNA amplification and define the boundaries of the amplicon region. As DNA fragments are frequently found both inside cells and in the extracellular environment, such as the serum of patients with cancer or other degenerative disorders, we propose that SFDA may be a common mechanism for DNA amplification in cancer cells, as well as a more general cause of DNA copy number variation

  5. A mechanism of gene amplification driven by small DNA fragments.

    Science.gov (United States)

    Mukherjee, Kuntal; Storici, Francesca

    2012-01-01

    DNA amplification is a molecular process that increases the copy number of a chromosomal tract and often causes elevated expression of the amplified gene(s). Although gene amplification is frequently observed in cancer and other degenerative disorders, the molecular mechanisms involved in the process of DNA copy number increase remain largely unknown. We hypothesized that small DNA fragments could be the trigger of DNA amplification events. Following our findings that small fragments of DNA in the form of DNA oligonucleotides can be highly recombinogenic, we have developed a system in the yeast Saccharomyces cerevisiae to capture events of chromosomal DNA amplification initiated by small DNA fragments. Here we demonstrate that small DNAs can amplify a chromosomal region, generating either tandem duplications or acentric extrachromosomal DNA circles. Small fragment-driven DNA amplification (SFDA) occurs with a frequency that increases with the length of homology between the small DNAs and the target chromosomal regions. SFDA events are triggered even by small single-stranded molecules with as little as 20-nt homology with the genomic target. A double-strand break (DSB) external to the chromosomal amplicon region stimulates the amplification event up to a factor of 20 and favors formation of extrachromosomal circles. SFDA is dependent on Rad52 and Rad59, partially dependent on Rad1, Rad10, and Pol32, and independent of Rad51, suggesting a single-strand annealing mechanism. Our results reveal a novel molecular model for gene amplification, in which small DNA fragments drive DNA amplification and define the boundaries of the amplicon region. As DNA fragments are frequently found both inside cells and in the extracellular environment, such as the serum of patients with cancer or other degenerative disorders, we propose that SFDA may be a common mechanism for DNA amplification in cancer cells, as well as a more general cause of DNA copy number variation in nature. PMID

  6. Complementary weak-value amplification with concatenated postselections

    CERN Document Server

    Viza, Gerardo I; Liu, Wei-Tao; Howell, John C

    2016-01-01

    We measure a transverse momentum kick in a Sagnac interferometer using weak-value amplification with two postselections. The first postselection is controlled by a polarization dependent phase mismatch between both paths of a Sagnac interferometer and the second postselection is controlled by a polarizer at the exit port. By monitoring the darkport of the interferometer, we study the complementary amplification of the concatenated postselections, where the polarization extinction ratio is greater than the contrast of the spatial interference. In this case, we find an improvement in the amplification of the signal of interest by introducing a second postselection to the system.

  7. Amplification and chromosomal dispersion of human endogenous retroviral sequences

    International Nuclear Information System (INIS)

    Endogenous retroviral sequences have undergone amplification events involving both viral and flanking cellular sequences. The authors cloned members of an amplified family of full-length endogenous retroviral sequences. Genomic blotting, employing a flanking cellular DNA probe derived from a member of this family, revealed a similar array of reactive bands in both humans and chimpanzees, indicating that an amplification event involving retroviral and associated cellular DNA sequences occurred before the evolutionary separation of these two primates. Southern analyses of restricted somatic cell hybrid DNA preparations suggested that endogenous retroviral segments are widely dispersed in the human genome and that amplification and dispersion events may be linked

  8. Amplification of Spin Waves by Thermal Spin-Transfer Torque

    Science.gov (United States)

    Padrón-Hernández, E.; Azevedo, A.; Rezende, S. M.

    2011-11-01

    We observe amplification of spin-wave packets propagating along a film of single-crystal yttrium iron garnet subject to a transverse temperature gradient. The spin waves are excited and detected with standard techniques used in magnetostatic microwave delay lines in the 1-2 GHz frequency range. The amplification is attributed to the action of a thermal spin-transfer torque acting on the magnetization that opposes the relaxation and which is created by spin currents generated through the spin-Seebeck effect. The experimental data are interpreted with a spin-wave model that gives an amplification gain in very good agreement with the data.

  9. Amplification and chromosomal dispersion of human endogenous retroviral sequences

    Energy Technology Data Exchange (ETDEWEB)

    Steele, P.E.; Martin, M.A.; Rabson, A.B.; Bryan, T.; O' Brien, S.J.

    1986-09-01

    Endogenous retroviral sequences have undergone amplification events involving both viral and flanking cellular sequences. The authors cloned members of an amplified family of full-length endogenous retroviral sequences. Genomic blotting, employing a flanking cellular DNA probe derived from a member of this family, revealed a similar array of reactive bands in both humans and chimpanzees, indicating that an amplification event involving retroviral and associated cellular DNA sequences occurred before the evolutionary separation of these two primates. Southern analyses of restricted somatic cell hybrid DNA preparations suggested that endogenous retroviral segments are widely dispersed in the human genome and that amplification and dispersion events may be linked.

  10. Preparation of DNA-containing extract for PCR amplification

    Science.gov (United States)

    Dunbar, John M.; Kuske, Cheryl R.

    2006-07-11

    Environmental samples typically include impurities that interfere with PCR amplification and DNA quantitation. Samples of soil, river water, and aerosol were taken from the environment and added to an aqueous buffer (with or without detergent). Cells from the sample are lysed, releasing their DNA into the buffer. After removing insoluble cell components, the remaining soluble DNA-containing extract is treated with N-phenacylthiazolium bromide, which causes rapid precipitation of impurities. Centrifugation provides a supernatant that can be used or diluted for PCR amplification of DNA, or further purified. The method may provide a DNA-containing extract sufficiently pure for PCR amplification within 5–10 minutes.

  11. PCR amplification on microarrays of gel immobilized oligonucleotides

    Science.gov (United States)

    Strizhkov, Boris; Tillib, Sergei; Mikhailovich, Vladimir; Mirzabekov, Andrei

    2003-11-04

    The invention relates two general methods for performing PCR amplification, combined with the detection and analysis of the PCR products on a microchip. In the first method, the amplification occurs both outside and within a plurality of gel pads on a microchip, with at least one oligonucleotide primer immobilized in a gel pad. In the second method, PCR amplification also takes place within gel pads on a microchip, but the pads are surrounded by a hydrophobic liquid such as that which separates the individual gel pads into environments which resemble micro-miniaturized test tubes.

  12. Raman amplification in the coherent wave-breaking regime.

    Science.gov (United States)

    Farmer, J P; Pukhov, A

    2015-12-01

    In regimes far beyond the wave-breaking threshold of Raman amplification, we show that significant amplification can occur after the onset of wave breaking, before phase mixing destroys the coherent coupling between pump, probe, and plasma wave. Amplification in this regime is therefore a transient effect, with the higher-efficiency "coherent wave-breaking" (CWB) regime accessed by using a short, intense probe. Parameter scans illustrate the marked difference in behavior between below wave breaking, in which the energy-transfer efficiency is high but total energy transfer is low, wave breaking, in which efficiency is low, and CWB, in which moderate efficiencies allow the highest total energy transfer. PMID:26764840

  13. Prenatal screening and genetics

    DEFF Research Database (Denmark)

    Alderson, P; Aro, A R; Dragonas, T;

    2001-01-01

    Although the term 'genetic screening' has been used for decades, this paper discusses how, in its most precise meaning, genetic screening has not yet been widely introduced. 'Prenatal screening' is often confused with 'genetic screening'. As we show, these terms have different meanings, and we...... examine definitions of the relevant concepts in order to illustrate this point. The concepts are i) prenatal, ii) genetic screening, iii) screening, scanning and testing, iv) maternal and foetal tests, v) test techniques and vi) genetic conditions. So far, prenatal screening has little connection...... with precisely defined genetics. There are benefits but also disadvantages in overstating current links between them in the term genetic screening. Policy making and professional and public understandings about screening could be clarified if the distinct meanings of prenatal screening and genetic screening were...

  14. Recombinase polymerase and enzyme-linked immunosorbent assay as a DNA amplification-detection strategy for food analysis

    International Nuclear Information System (INIS)

    Graphical abstract: -- Highlights: •Recombinase polymerase amplification is a powerful DNA method operating at 40 °C. •The combination RPA–ELISA gives excellent performances for high-throughput analysis. •Screening of food safety threats has been done using standard laboratory equipment. •Allergens, GMOs, bacteria, and fungi have been successfully determined. -- Abstract: Polymerase chain reaction in conjunction with enzyme-linked immunosorbent assay (PCR–ELISA) is a well-established technique that provides a suitable rapid, sensitive, and selective method for a broad range of applications. However, the need for precise rapid temperature cycling of PCR is an important drawback that can be overcome by employing isothermal amplification reactions such as recombinase polymerase amplification (RPA). The RPA–ELISA combination is proposed for amplification at a low, constant temperature (40 °C) in a short time (40 min), for the hybridisation of labelled products to specific 5′-biotinylated probes/streptavidin in coated microtiter plates at room temperature, and for detection by colorimetric immunoassay. RPA–ELISA was applied to screen common safety threats in foodstuffs, such as allergens (hazelnut, peanut, soybean, tomato, and maize), genetically modified organisms (P35S and TNOS), pathogenic bacteria (Salmonella sp. and Cronobacter sp.), and fungi (Fusarium sp.). Satisfactory sensitivity and reproducibility results were achieved for all the targets. The RPA–ELISA technique does away with thermocycling and provides a suitable sensitive, specific, and cost-effective method for routine applications, and proves particularly useful for resource-limited settings

  15. Recombinase polymerase and enzyme-linked immunosorbent assay as a DNA amplification-detection strategy for food analysis

    Energy Technology Data Exchange (ETDEWEB)

    Santiago-Felipe, S.; Tortajada-Genaro, L.A.; Puchades, R.; Maquieira, A., E-mail: amaquieira@qim.upv.es

    2014-02-06

    Graphical abstract: -- Highlights: •Recombinase polymerase amplification is a powerful DNA method operating at 40 °C. •The combination RPA–ELISA gives excellent performances for high-throughput analysis. •Screening of food safety threats has been done using standard laboratory equipment. •Allergens, GMOs, bacteria, and fungi have been successfully determined. -- Abstract: Polymerase chain reaction in conjunction with enzyme-linked immunosorbent assay (PCR–ELISA) is a well-established technique that provides a suitable rapid, sensitive, and selective method for a broad range of applications. However, the need for precise rapid temperature cycling of PCR is an important drawback that can be overcome by employing isothermal amplification reactions such as recombinase polymerase amplification (RPA). The RPA–ELISA combination is proposed for amplification at a low, constant temperature (40 °C) in a short time (40 min), for the hybridisation of labelled products to specific 5′-biotinylated probes/streptavidin in coated microtiter plates at room temperature, and for detection by colorimetric immunoassay. RPA–ELISA was applied to screen common safety threats in foodstuffs, such as allergens (hazelnut, peanut, soybean, tomato, and maize), genetically modified organisms (P35S and TNOS), pathogenic bacteria (Salmonella sp. and Cronobacter sp.), and fungi (Fusarium sp.). Satisfactory sensitivity and reproducibility results were achieved for all the targets. The RPA–ELISA technique does away with thermocycling and provides a suitable sensitive, specific, and cost-effective method for routine applications, and proves particularly useful for resource-limited settings.

  16. Thermal amplification of field-correlation harvesting

    CERN Document Server

    Brown, Eric G

    2013-01-01

    We study the harvesting of quantum and classical correlations from a hot scalar field in a periodic cavity by a pair of spatially separated oscillator-detectors. Specifically, we utilize non-perturbative and exact (non-numerical) techniques to solve for the evolution of the detectors-field system and then we examine how the entanglement, Gaussian quantum discord, and mutual information obtained by the detectors change with the temperature of the field. While (as expected) the harvested entanglement rapidly decays to zero as temperature is increased, we find remarkably that both the mutual information and the discord can actually be increased by multiple orders of magnitude via increasing the temperature. We go on to explain this phenomenon by taking advantage of the translational invariance of the field and use this to make accurate predictions of the behavior of thermal amplification; by this we also introduce a new perspective on field-correlation harvesting that we feel is worthy of consideration in its ow...

  17. Local Runup Amplification By Resonant Wave Interactions

    CERN Document Server

    Stefanakis, Themistoklis; Dutykh, Denys

    2011-01-01

    Until now the analysis of long wave runup on a plane beach has been focused on finding its maximum value, failing to capture the existence of resonant regimes. One-dimensional numerical simulations in the framework of the Nonlinear Shallow Water Equations (NSWE) are used to investigate the Boundary Value Problem (BVP) for plane and non-trivial beaches. Monochromatic waves, as well as virtual wave-gage recordings from real tsunami simulations, are used as forcing conditions to the BVP. Resonant phenomena between the incident wavelength and the beach slope are found to occur, which result in enhanced runup of non-leading waves. The evolution of energy reveals the existence of a quasi-periodic state for the case of sinusoidal waves, the energy level of which, as well as the time required to reach that state, depend on the incident wavelength for a given beach slope. Dispersion is found to slightly reduce the value of maximum runup, but not to change the overall picture. Runup amplification occurs for both leadin...

  18. AGAPE Andromeda Gravitational Amplification Pixel Experiment

    CERN Document Server

    Ansari, R; Baillon, Paul; Bouquet, A; Coupinot, G; Coutures, C; Ghesquière, C; Giraud-Héraud, Yannick; Gondolo, P; Hecquet, J; Kaplan, J; Le Du, Y; Melchior, A L; Moniez, M; Picat, J P; Soucail, G

    1999-01-01

    The aim of the AGAPE (Andromeda Gravitational Amplification Pixel Experiment), experiment which has been first proposed in June 1992 is to examine the distribution of massive astrophysical compact halo objects ((MACHO's) which possibly are in the galactic haloes and which could account for the missing dark matter. Those objects have a mass which is a fraction of solar mass and could be detected by gravitational microlensing: the light of a star is amplified when a MACHO is crossing its line of sight from the earth. This technique has been proposed by Paczy\\'nski in 1986. The AGAPE collaboration applies this technique in an original way by using, as target stars, the stars of another galaxy without resolving them. The recent progresses in photometry with CCD allow now to see tiny variations of the surface brightness of a galaxy like M~31. Those tiny variations can be the result of a single microlensing event on the background stars contributing to the surface brightness. The AGAPE collaboration has now cumulat...

  19. Thermodynamic analysis of quantum light amplification

    CERN Document Server

    Tannor, D J

    2006-01-01

    Thermodynamics of a three-level maser was studied in the pioneering work of Scovil and Schulz-DuBois [Phys. Rev. Lett. 2, 262 (1959)]. In this work we consider the same three-level model, but treat both the matter and light quantum mechanically. Specifically, we analyze an extended (three-level) dissipative Jaynes-Cummings model (ED-JCM) within the framework of a quantum heat engine, using novel formulas for heat flux and power in bipartite systems introduced in our previous work [E. Boukobza and D. J. Tannor, PRA (in press)]. Amplification of the selected cavity mode occurs even in this simple model, as seen by a positive steady state power. However, initial field coherence is lost, as seen by the decaying off-diagonal field density matrix elements, and by the Husimi-Kano Q function. We show that after an initial transient time the field's entropy rises linearly during the operation of the engine, which we attribute to the dissipative nature of the evolution and not to matter-field entanglement. We show that...

  20. Small Sample Whole-Genome Amplification

    Energy Technology Data Exchange (ETDEWEB)

    Hara, C A; Nguyen, C P; Wheeler, E K; Sorensen, K J; Arroyo, E S; Vrankovich, G P; Christian, A T

    2005-09-20

    Many challenges arise when trying to amplify and analyze human samples collected in the field due to limitations in sample quantity, and contamination of the starting material. Tests such as DNA fingerprinting and mitochondrial typing require a certain sample size and are carried out in large volume reactions; in cases where insufficient sample is present whole genome amplification (WGA) can be used. WGA allows very small quantities of DNA to be amplified in a way that enables subsequent DNA-based tests to be performed. A limiting step to WGA is sample preparation. To minimize the necessary sample size, we have developed two modifications of WGA: the first allows for an increase in amplified product from small, nanoscale, purified samples with the use of carrier DNA while the second is a single-step method for cleaning and amplifying samples all in one column. Conventional DNA cleanup involves binding the DNA to silica, washing away impurities, and then releasing the DNA for subsequent testing. We have eliminated losses associated with incomplete sample release, thereby decreasing the required amount of starting template for DNA testing. Both techniques address the limitations of sample size by providing ample copies of genomic samples. Carrier DNA, included in our WGA reactions, can be used when amplifying samples with the standard purification method, or can be used in conjunction with our single-step DNA purification technique to potentially further decrease the amount of starting sample necessary for future forensic DNA-based assays.

  1. Increasing live birth rate by preimplantation genetic screening of pooled polar bodies using array comparative genomic hybridization.

    Directory of Open Access Journals (Sweden)

    Michael Feichtinger

    Full Text Available Meiotic errors during oocyte maturation are considered the major contributors to embryonic aneuploidy and failures in human IVF treatment. Various technologies have been developed to screen polar bodies, blastomeres and trophectoderm cells for chromosomal aberrations. Array-CGH analysis using bacterial artificial chromosome (BAC arrays is widely applied for preimplantation genetic diagnosis (PGD using single cells. Recently, an increase in the pregnancy rate has been demonstrated using array-CGH to evaluate trophectoderm cells. However, in some countries, the analysis of embryonic cells is restricted by law. Therefore, we used BAC array-CGH to assess the impact of polar body analysis on the live birth rate. A disadvantage of polar body aneuploidy screening is the necessity of the analysis of both the first and second polar bodies, resulting in increases in costs for the patient and complex data interpretation. Aneuploidy screening results may sometimes be ambiguous if the first and second polar bodies show reciprocal chromosomal aberrations. To overcome this disadvantage, we tested a strategy involving the pooling of DNA from both polar bodies before DNA amplification. We retrospectively studied 351 patients, of whom 111 underwent polar body array-CGH before embryo transfer. In the group receiving pooled polar body array-CGH (aCGH analysis, 110 embryos were transferred, and 29 babies were born, corresponding to live birth rates of 26.4% per embryo and 35.7% per patient. In contrast, in the control group, the IVF treatment was performed without preimplantation genetic screening (PGS. For this group, 403 embryos were transferred, and 60 babies were born, resulting in live birth rates of 14.9% per embryo and 22.7% per patient. In conclusion, our data show that in the aCGH group, the use of aneuploidy screening resulted in a significantly higher live birth rate compared with the control group, supporting the benefit of PGS for IVF couples in

  2. Virtual screening of bioassay data

    Directory of Open Access Journals (Sweden)

    Schierz Amanda C

    2009-12-01

    Full Text Available Abstract Background There are three main problems associated with the virtual screening of bioassay data. The first is access to freely-available curated data, the second is the number of false positives that occur in the physical primary screening process, and finally the data is highly-imbalanced with a low ratio of Active compounds to Inactive compounds. This paper first discusses these three problems and then a selection of Weka cost-sensitive classifiers (Naive Bayes, SVM, C4.5 and Random Forest are applied to a variety of bioassay datasets. Results Pharmaceutical bioassay data is not readily available to the academic community. The data held at PubChem is not curated and there is a lack of detailed cross-referencing between Primary and Confirmatory screening assays. With regard to the number of false positives that occur in the primary screening process, the analysis carried out has been shallow due to the lack of cross-referencing mentioned above. In six cases found, the average percentage of false positives from the High-Throughput Primary screen is quite high at 64%. For the cost-sensitive classification, Weka's implementations of the Support Vector Machine and C4.5 decision tree learner have performed relatively well. It was also found, that the setting of the Weka cost matrix is dependent on the base classifier used and not solely on the ratio of class imbalance. Conclusions Understandably, pharmaceutical data is hard to obtain. However, it would be beneficial to both the pharmaceutical industry and to academics for curated primary screening and corresponding confirmatory data to be provided. Two benefits could be gained by employing virtual screening techniques to bioassay data. First, by reducing the search space of compounds to be screened and secondly, by analysing the false positives that occur in the primary screening process, the technology may be improved. The number of false positives arising from primary screening leads to

  3. Detection of HIV cDNA Point Mutations with Rolling-Circle Amplification Arrays

    Directory of Open Access Journals (Sweden)

    Zhongwei Wu

    2010-01-01

    Full Text Available In this paper we describe an isothermal rolling-circle amplification (RCA protocol to detect gene point mutations on chips. The method is based on an allele-specific oligonucleotide circularization mediated by a special DNA ligase. The probe is circularized when perfect complementary sequences between the probe oligonucleotide and HIV cDNA gene. Mismatches around the ligation site can prevent probe circularization. The circularized probe (C-probe can be amplified by rolling circle amplification to generate multimeric singlestranded DNA (ssDNA under isothermal conditions. There are four sequence regions to bind respectively with fluorescent probe, RCA primer, solid probe and HIV cDNA template in the C-probe which we designed. These ssDNA products are hybridized with fluorescent probes and solid probes which are immobilized on a glass slide composing a regular microarray pattern. The fluorescence signals can be monitored by a scanner in the presence of HIV cDNA templates, whereas the probes cannot be circularized and signal of fluorescence cannot be found. The RCA array has capability of high-throughput detection of the point mutation and the single-nucleotide polymorphism (SNP.The development of C-probe-based technologies offers a promising prospect for situ detection, microarray, molecular diagnosis, single nucleotide polymorphism, and whole genome amplification.

  4. Real-time quantitative nicking endonuclease-mediated isothermal amplification with small molecular beacons.

    Science.gov (United States)

    Xu, Wentao; Wang, Chenguang; Zhu, Pengyu; Guo, Tianxiao; Xu, Yuancong; Huang, Kunlun; Luo, Yunbo

    2016-04-21

    Techniques of isothermal amplification have recently made great strides, and have generated significant interest in the field of point-of-care detection. Nicking endonuclease-mediated isothermal amplification (NEMA) is an example of simple isothermal technology. In this paper, a real-time quantitative nicking endonuclease-mediated isothermal amplification with small molecular beacons (SMB-NEMA) of improved specificity and sensitivity is described. First, we optimized the prohibition of de novo synthesis by choosing Nt·BstNBI endonuclease. Second, the whole genome was successfully amplified with Nt·BstNBI (6 U), betaine (1 M) and trehalose (60 mM) for the first time. Third, we achieved 10 pg sensitivity for the first time after adding a small molecular beacon that spontaneously undergoes a conformational change when hybridizing to target, and the practical test validated the assay's application. The small molecular beacon has a similar melting temperature to the reaction temperature, but is approximately 10 bp shorter than the length of a traditional molecular beacon. A new threshold regulation was also established for isothermal conditions. Finally, we established a thermodynamic model for designing small molecular beacons. This multistate model is more correct than the traditional algorithm. This theoretical and practical basis will help us to monitor SMB-NEMA in a quantitative way. In summary, our SMB-NEMA method allows the simple, specific and sensitive assessment of isothermal DNA quantification. PMID:27027375

  5. A Novel Low Temperature PCR Assured High-Fidelity DNA Amplification

    Directory of Open Access Journals (Sweden)

    Shaoxia Zhou

    2013-06-01

    Full Text Available As previously reported, a novel low temperature (LoTemp polymerase chain reaction (PCR catalyzed by a moderately heat-resistant (MHR DNA polymerase with a chemical-assisted denaturation temperature set at 85 °C instead of the conventional 94–96 °C can achieve high-fidelity DNA amplification of a target DNA, even after up to 120 PCR thermal cycles. Furthermore, such accurate amplification is not achievable with conventional PCR. Now, using a well-recognized L1 gene segment of the human papillomavirus (HPV type 52 (HPV-52 as the template for experiments, we demonstrate that the LoTemp high-fidelity DNA amplification is attributed to an unusually high processivity and stability of the MHR DNA polymerase whose high fidelity in template-directed DNA synthesis is independent of non-existent 3'–5' exonuclease activity. Further studies and understanding of the characteristics of the LoTemp PCR technology may facilitate implementation of DNA sequencing-based diagnostics at the point of care in community hospital laboratories.

  6. Development of separation technology for the removal of radium-223 from decayed thorium-227 in drug formulations. Material screening and method development.

    Science.gov (United States)

    Frenvik, Janne Olsen; Kristensen, Solveig; Ryan, Olav B

    2016-08-01

    Targeted thorium conjugates are currently being investigated as a new class of alpha-radiopharmaceuticals. The natural decay of thorium-227 ((227)Th) results in the ingrowth of radium-223 ((223)Ra). Consideration must, therefore, be given to define acceptable limits of (223)Ra in the drug product at the time of dose administration. By effective sequestration of (223)Ra, we aim to improve the radiochemical purity and extend the effective user window of drug products containing (227)Th. (223)Ra is the first progeny of (227)Th and the only one with a long half-life (days). We have, therefore, focused on the removal of this specific species since the progenies of (223)Ra will have a very limited lifetime in the formulation once (223)Ra is removed. In this study, we investigated a multitude of materials for their ability to reduce the (223)Ra level by: (1) passive diffusion or (2) by cartridge filtration on gravity columns. In addition, we probe the compatibility of these materials in the presence of antibody trastuzumab to assess the level of protein binding and estimate the quenching of radiolysis by binding of radionuclides. A screening matrix of organic and inorganic materials was established, i.e. strontium and calcium alginate gel beads, distearoyl phosphatidylglycerol (DSPG) liposomes, ceramic hydroxyapatite, Zeolite UOP type 4A and cation exchange resins AG50W-X8 and SOURCE 30S. First, passive diffusional uptake of (223)Ra by suspended materials present in the formulation was measured as a decrease in sample radioactivity after separation. Second, selected materials were packed on gravity columns in order to evaluate the efficiency of column separation versus diffusional adsorption. The retention of (223)Ra and (227)Th were characterized by measuring the radioactivity in the eluate and on the columns. Finally, the compatibility between trastuzumab, as a selected model antibody, and suspensions of the binding materials was analyzed during storage of the drug

  7. Ultrabroadband noncollinear optical parametric amplification with LBO crystal.

    Science.gov (United States)

    Zhao, Baozhen; Jiang, Yongliang; Sueda, Keiich; Miyanaga, Noriaki; Kobayashi, Takayoshi

    2008-11-10

    Ultrabroadband visible noncollinear optical parametric amplification (NOPA) was achieved in an LBO crystal, with a continuum seed pulse generated from a sapphire plate. The spectral bandwidth of the amplified visible pulse was about 200 nm, which can support sub-5 fs pulse amplification. An amplified output of 0.21 microJ with an average gain of about 210 was achieved. This provides, to the best of our knowledge, the first-time demonstration of such broadband amplification with a biaxial nonlinear optical crystal. Both the simulation and experimental results indicate that the LBO has a great potential as nonlinear medium in power amplifier for TW to PW noncollinear optical parametric chirped pulse amplification (NOPCPA) systems. PMID:19581976

  8. Real burst traffic amplification in optically gain clamped amplifier

    OpenAIRE

    Ennser, Karin; Taccheo, Stefano; Careglio, Davide; Solé Pareta, Josep; Aracil Rico, Javier

    2008-01-01

    Optical burst amplification in a gain-stabilized amplifier is theoretically investigated using real burst traffic data. The results show that excellent performance are obtained for WDM transmission with negligible interplay due to burst arrival statistics.

  9. Prenatal screening and genetics

    NARCIS (Netherlands)

    Alderson, P.; Aro, A.R.; Dragonas, T.; Ettorre, E.; Hemminki, E.; Jalinoja, P.; Santalahti, P.; Tijmstra, T.

    2001-01-01

    Although the term 'genetic screening' has been used for decades, this paper discusses how, in its most precise meaning, genetic screening has not yet been widely introduced. 'Prenatal screening' is often confused with 'genetic screening'. As we show, these terms have different meanings, and we exami

  10. Sources of Error in Mammalian Genetic Screens.

    Science.gov (United States)

    Sack, Laura Magill; Davoli, Teresa; Xu, Qikai; Li, Mamie Z; Elledge, Stephen J

    2016-01-01

    Genetic screens are invaluable tools for dissection of biological phenomena. Optimization of such screens to enhance discovery of candidate genes and minimize false positives is thus a critical aim. Here, we report several sources of error common to pooled genetic screening techniques used in mammalian cell culture systems, and demonstrate methods to eliminate these errors. We find that reverse transcriptase-mediated recombination during retroviral replication can lead to uncoupling of molecular tags, such as DNA barcodes (BCs), from their associated library elements, leading to chimeric proviral genomes in which BCs are paired to incorrect ORFs, shRNAs, etc This effect depends on the length of homologous sequence between unique elements, and can be minimized with careful vector design. Furthermore, we report that residual plasmid DNA from viral packaging procedures can contaminate transduced cells. These plasmids serve as additional copies of the PCR template during library amplification, resulting in substantial inaccuracies in measurement of initial reference populations for screen normalization. The overabundance of template in some samples causes an imbalance between PCR cycles of contaminated and uncontaminated samples, which results in a systematic artifactual depletion of GC-rich library elements. Elimination of contaminating plasmid DNA using the bacterial endonuclease Benzonase can restore faithful measurements of template abundance and minimize GC bias. PMID:27402361

  11. Methods for microbial DNA extraction from soil for PCR amplification

    OpenAIRE

    Yeates C; Gillings, MR; Davison AD; Altavilla N; Veal DA

    1998-01-01

    Amplification of DNA from soil is often inhibited by co-purified contaminants. A rapid, inexpensive, large-scale DNA extraction method involving minimal purification has been developed that is applicable to various soil types (1). DNA is also suitable for PCR amplification using various DNA targets. DNA was extracted from 100g of soil using direct lysis with glass beads and SDS followed by potassium acetate precipitation, polyethylene glycol precipitation, phenol extraction and isopropanol pr...

  12. Pulse Distortion in Saturated Fiber Optical Parametric Chirped Pulse Amplification

    DEFF Research Database (Denmark)

    Lali-Dastjerdi, Zohreh; Da Ros, Francesco; Rottwitt, Karsten;

    2012-01-01

    Fiber optical parametric chirped pulse amplification is experimentally compared for different chirped pulses in the picosecond regime. The amplified chirped pulses show distortion appearing as pedestals after recompression when the amplifier is operated in saturation.......Fiber optical parametric chirped pulse amplification is experimentally compared for different chirped pulses in the picosecond regime. The amplified chirped pulses show distortion appearing as pedestals after recompression when the amplifier is operated in saturation....

  13. Loop-Mediated Amplification Accelerated by Stem Primers

    OpenAIRE

    Laurence Tisi; Guy Kiddle; Olga Gandelman; Rebecca Jackson

    2011-01-01

    Isothermal nucleic acid amplifications (iNAATs) have become an important alternative to PCR for in vitro molecular diagnostics in all fields. Amongst iNAATs Loop-mediated amplification (LAMP) has gained much attention over the last decade because of the simplicity of hardware requirements. LAMP demonstrates performance equivalent to that of PCR, but its application has been limited by the challenging primer design. The design of six primers in LAMP requires a selection of eight priming sites ...

  14. Controllable Amplification of Entanglement for Two Qutrits under Decoherence

    Institute of Scientific and Technical Information of China (English)

    ZHENG Qiang; XIE Xiao-Yao; ZHI Qi-Jun; REN Zhong-Zhou

    2011-01-01

    Entanglement dynamics of a two-qutrit Heisenberg spin chain with the external magnetic fields and DM interaction under the intrinsic decoherence is investigated. Depending on whether there is inhomogeneous magnetic field,the entanglement amplification, i.e. the phenomenon that the finally stable entanglement is bigger than that of the initial one, is found for one kind of initial states. The reasons for the controllable entanglement amplification are discussed.

  15. Measurement-Based Noiseless Linear Amplification for Quantum Communication

    OpenAIRE

    Chrzanowski, Helen M.; Walk, Nathan; Assad, Syed M.; Janousek, Jiri; Hosseini, Sara; Ralph, Timothy C.; Symul, Thomas; Lam, Ping Koy

    2014-01-01

    Entanglement distillation is an indispensable ingredient in extended quantum communication networks. Distillation protocols are necessarily non-deterministic and require advanced experimental techniques such as noiseless amplification. Recently it was shown that the benefits of noiseless amplification could be extracted by performing a post-selective filtering of the measurement record to improve the performance of quantum key distribution. We apply this protocol to entanglement degraded by t...

  16. On the amplification of acoustic phonons in carbon nanotube

    OpenAIRE

    Dompreh, K. A.; Mensah, N. G.; Sakyi-Arthur, D.; Mensah, S. Y.

    2016-01-01

    We present a theoretical study of acoustic phonons amplification in Carbon Nanotubes (CNT). The phenomenon is via Cerenkov emission (CE) of acoustic phonons using intraband transitions proposed by Mensah et. al.,~\\cite{1} in Semiconductor Superlattices (SSL) and confirmed in ~\\cite{2}. From this, an asymmetric graph of $\\Gamma^{CNT}$ on $\\frac{V_d}{V_s}$ and $\\Omega\\tau$ were obtained where amplification ($\\Gamma_{amp}^{CNT}$) $>>$ absorption ($\\Gamma_{abs}^{CNT}$). The ratio, $\\frac{\\vert \\G...

  17. Electrical and Electrochemical Monitoring of Nucleic Acid Amplification

    OpenAIRE

    Goda, Tatsuro; Tabata, Miyuki; Miyahara, Yuji

    2015-01-01

    Nucleic acid amplification is a gold standard technique for analyzing a tiny amount of nucleotides in molecular biology, clinical diagnostics, food safety, and environmental testing. Electrical and electrochemical monitoring of the amplification process draws attention over conventional optical methods because of the amenability toward point-of-care applications as there is a growing demand for nucleic acid sensing in situations outside the laboratory. A number of electrical and electrochemic...

  18. Aerosol Lidar for the Relative Backscatter Amplification Measurements

    Science.gov (United States)

    Razenkov, Igor A.; Banakh, Victor A.; Nadeev, Alexander I.

    2016-06-01

    Backscatter amplification presents only in a turbulent atmosphere, when the laser beam is propagates twice through the same inhomogeneities. We proposed technical solution to detect backscatter amplification. An aerosol micro pulse lidar with a beam expansion via receiving telescope was built to study this effect. Our system allows simultaneous detection of two returns from the same scattering volume: exactly on the axis of the laser beam and off the axis.

  19. Radioactive wastes and the social amplification of risk

    OpenAIRE

    Roger E. Kasperson; Emel, Jacque; Goble, Robert; Hohenemser, Christoph; Kasperson, Jeanne X.; Renn, Ortwin

    1987-01-01

    A significant problem in radioactive waste facility siting is that apparent small risks or minor risks events produce substantial public concern and social impacts. The reasons for this difference in public health and societal impacts is not well understood. This paper explores the issues involved in the social amplification of risk, using the risk associated with site characterization as the example. Noteworthy as sources of amplification are the infomation flow associated with risks and ris...

  20. Fingerprinting Internet DNS Amplification DDoS Activities

    OpenAIRE

    Fachkha, Claude; Bou-Harb, Elias; Debbabi, Mourad

    2013-01-01

    This work proposes a novel approach to infer and characterize Internet-scale DNS amplification DDoS attacks by leveraging the darknet space. Complementary to the pioneer work on inferring Distributed Denial of Service (DDoS) activities using darknet, this work shows that we can extract DDoS activities without relying on backscattered analysis. The aim of this work is to extract cyber security intelligence related to DNS Amplification DDoS activities such as detection period, attack duration, ...

  1. Thermodynamic analysis of quantum light amplification

    Science.gov (United States)

    Boukobza, E.; Tannor, D. J.

    2006-12-01

    Thermodynamics of a three-level maser was studied in the pioneering work of Scovil and Schulz-DuBois [Phys. Rev. Lett. 2, 262 (1959)]. In this work we consider the same three-level model, but treat both the matter and the light quantum mechanically. Specifically, we analyze an extended (three-level) dissipative (ED) Jaynes-Cummings model (JCM) within the framework of a quantum heat engine, using formulas for heat flux and power in bipartite systems introduced in our previous work [E. Boukobza and D. J. Tannor Phys. Rev. A 74, 063823 (2006)] Amplification of the selected cavity mode occurs even in this simple model, as seen by a positive steady state power. However, initial field coherence is lost, as seen by the decaying off-diagonal field density matrix elements, and by the Husimi-Kano Q function. We show that after an initial transient time the field’s entropy rises linearly during the operation of the engine, which we attribute to the dissipative nature of the evolution and not to matter-field entanglement. We show that the second law of thermodynamics is satisfied in two formulations (Clausius, Carnot) and that the efficiency of the ED JCM heat engine agrees with that defined intuitively by Scovil and Schulz-DuBois. Finally, we compare the steady state heat flux and power of the fully quantum model with the semiclassical counterpart of the ED JCM, and derive the engine efficiency formula of Scovil and Schulz-DuBois analytically from fundamental thermodynamic fluxes.

  2. Thermodynamic analysis of quantum light amplification

    International Nuclear Information System (INIS)

    Thermodynamics of a three-level maser was studied in the pioneering work of Scovil and Schulz-DuBois [Phys. Rev. Lett. 2, 262 (1959)]. In this work we consider the same three-level model, but treat both the matter and the light quantum mechanically. Specifically, we analyze an extended (three-level) dissipative (ED) Jaynes-Cummings model (JCM) within the framework of a quantum heat engine, using formulas for heat flux and power in bipartite systems introduced in our previous work [E. Boukobza and D. J. Tannor Phys. Rev. A 74, 063823 (2006)] Amplification of the selected cavity mode occurs even in this simple model, as seen by a positive steady state power. However, initial field coherence is lost, as seen by the decaying off-diagonal field density matrix elements, and by the Husimi-Kano Q function. We show that after an initial transient time the field's entropy rises linearly during the operation of the engine, which we attribute to the dissipative nature of the evolution and not to matter-field entanglement. We show that the second law of thermodynamics is satisfied in two formulations (Clausius, Carnot) and that the efficiency of the ED JCM heat engine agrees with that defined intuitively by Scovil and Schulz-DuBois. Finally, we compare the steady state heat flux and power of the fully quantum model with the semiclassical counterpart of the ED JCM, and derive the engine efficiency formula of Scovil and Schulz-DuBois analytically from fundamental thermodynamic fluxes

  3. Magnetic Field Amplification and Blazar Flares

    Directory of Open Access Journals (Sweden)

    Chen Xuhui

    2013-12-01

    Full Text Available Recent multiwavelength observations of PKS 0208-512 by SMARTS, Fermi, and Swift revealed that γ-ray and optical light curves of this flat spectrum radio quasars are highly correlated, but with an exception of one large optical flare having no corresponding gamma-ray activity or even detection. On the other hand, recent advances in SNRs observations and plasma simulations both reveal that magnetic field downstream of astrophysical shocks can be largely amplified beyond simple shock compression. These amplifications, along with their associated particle acceleration, might contribute to blazar flares, including the peculiar flare of PKS 0208-512. Using our time dependent multizone blazar emission code, we evaluate several scenarios that may represent such phenomena. This code combines Monte Carlo method that tracks the radiative processes including inverse Compton scattering, and Fokker-Planck equation that follows the cooling and acceleration of particles. It is a comprehensive time dependent code that fully takes into account the light travel time effects. In this study, both the changes of the magnetic field and acceleration efficiency are explored as the cause of blazar flares. Under these assumption, synchrotron self-Compton and external Compton scenarios produce distinct features that favor the external Compton scenario. The optical flares with/without gamma-ray counterparts can be explained by different allocations of energy between the magnetization and particle acceleration, which in turn can be affected by the relative orientation between the magnetic field and the shock flow. We compare the details of the observations and simulation, and highlight what implications this study has on our understanding of relativistic jets.

  4. Targeting MET Amplification as a New Oncogenic Driver

    International Nuclear Information System (INIS)

    Certain genetically defined cancers are dependent on a single overactive oncogene for their proliferation and survival, a phenomenon known as “oncogene addiction”. A new generation of drugs that selectively target such “driver oncogenes” manifests a clinical efficacy greater than that of conventional chemotherapy in appropriate genetically defined patients. MET is a proto-oncogene that encodes a receptor tyrosine kinase, and aberrant activation of MET signaling occurs in a subset of advanced cancers as result of various genetic alterations including gene amplification, polysomy, and gene mutation. Our preclinical studies have shown that inhibition of MET signaling either with the small-molecule MET inhibitor crizotinib or by RNA interference targeted to MET mRNA resulted in marked antitumor effects in cancer cell lines with MET amplification both in vitro and in vivo. Furthermore, patients with non-small cell lung cancer or gastric cancer positive for MET amplification have shown a pronounced clinical response to crizotinib. Accumulating preclinical and clinical evidence thus suggests that MET amplification is an “oncogenic driver” and therefore a valid target for treatment. However, the prevalence of MET amplification has not been fully determined, possibly in part because of the difficulty in evaluating gene amplification. In this review, we provide a rationale for targeting this genetic alteration in cancer therapy

  5. Problems encountered when defining Arctic amplification as a ratio.

    Science.gov (United States)

    Hind, Alistair; Zhang, Qiong; Brattström, Gudrun

    2016-01-01

    In climate change science the term 'Arctic amplification' has become synonymous with an estimation of the ratio of a change in Arctic temperatures compared with a broader reference change under the same period, usually in global temperatures. Here, it is shown that this definition of Arctic amplification comes with a suite of difficulties related to the statistical properties of the ratio estimator itself. Most problematic is the complexity of categorizing uncertainty in Arctic amplification when the global, or reference, change in temperature is close to 0 over a period of interest, in which case it may be impossible to set bounds on this uncertainty. An important conceptual distinction is made between the 'Ratio of Means' and 'Mean Ratio' approaches to defining a ratio estimate of Arctic amplification, as they do not only possess different uncertainty properties regarding the amplification factor, but are also demonstrated to ask different scientific questions. Uncertainty in the estimated range of the Arctic amplification factor using the latest global climate models and climate forcing scenarios is expanded upon and shown to be greater than previously demonstrated for future climate projections, particularly using forcing scenarios with lower concentrations of greenhouse gases. PMID:27461918

  6. Targeting MET Amplification as a New Oncogenic Driver

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Hisato [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Okamoto, Isamu, E-mail: okamotoi@kokyu.med.kyushu-u.ac.jp [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Center for Clinical and Translational Research, Kyushu University Hospital, 3-1-1 Maidashi, Higashiku, Fukuoka 812-8582 (Japan); Okamoto, Wataru [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Division of Transrlational Research, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 6-5-1 Kashiwanoha, Kashiwa, Chiba 277-8577 (Japan); Tanizaki, Junko [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, HIM223, 450 Brookline Avenue, Boston, MA 02215 (United States); Nakagawa, Kazuhiko [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Nishio, Kazuto [Department of Genome Biology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan)

    2014-07-22

    Certain genetically defined cancers are dependent on a single overactive oncogene for their proliferation and survival, a phenomenon known as “oncogene addiction”. A new generation of drugs that selectively target such “driver oncogenes” manifests a clinical efficacy greater than that of conventional chemotherapy in appropriate genetically defined patients. MET is a proto-oncogene that encodes a receptor tyrosine kinase, and aberrant activation of MET signaling occurs in a subset of advanced cancers as result of various genetic alterations including gene amplification, polysomy, and gene mutation. Our preclinical studies have shown that inhibition of MET signaling either with the small-molecule MET inhibitor crizotinib or by RNA interference targeted to MET mRNA resulted in marked antitumor effects in cancer cell lines with MET amplification both in vitro and in vivo. Furthermore, patients with non-small cell lung cancer or gastric cancer positive for MET amplification have shown a pronounced clinical response to crizotinib. Accumulating preclinical and clinical evidence thus suggests that MET amplification is an “oncogenic driver” and therefore a valid target for treatment. However, the prevalence of MET amplification has not been fully determined, possibly in part because of the difficulty in evaluating gene amplification. In this review, we provide a rationale for targeting this genetic alteration in cancer therapy.

  7. Screening for amplification genomic loci and genes associated prognosis in gastric cancer

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Objective:We used a high-resolution array-based comparative genomic hybridization (aCGH) coupled with patient clinical information to identify prognosis-related genomic loci and genes.Methods: aCGH coupled with patient clinical information was applied to identify prognosis-related loci and genes with high-frequency recurrent gains in 129 GC cases. The candidate loci and genes were validated using an independent cohort of 384 cases through branched DNA signal ampliifcation analysis.Results:A copy number gain of three chromosome regions, namely, 8q22, 8q24and 20q11-q13, conferred poor survival for patients. In addition, MYC, TNFRSF11B, ESRP1, CSE1L and MMP9 were found to be well correlated. Further validation verified that only MYC and TNFRSF11B within 8q24 are related to survival. Patients with gains in both MYC and TNFRSF11B presented poorer survival than those with no gains, particularly those with non-cardia GC. Gains in both of these genes were also a signiifcant independent prognostic indicator.Conclusion:Copy number gains in MYC and TNFRSF11B located at 8q24are associated with survival in GC, particularly non-cardia GC.

  8. Detection of genetic variation in Hevea brasiliensis using the DNA amplification fingerprinting technique

    International Nuclear Information System (INIS)

    Earlier studies on genetic variation and genome analysis of Hevea brasiliensis were based primarily on restriction fragment length polymorphisms (RFLPs). Notwithstanding that the RFLP technique is a powerful tool, the technique is slow, laborious and requires highly polymorphic hybridization probes. The multiplex DAF technique was adopted. Pairs of random 10-mer oligonucleotide primers were tested for their ability to elicit DNA polymorphisms. Preliminary results indicated that the number of amplified products varied with the annealing temperature and the primer pairs. Although it was found that the annealing temperatures had to be varied for different primer pairs in order to achieve satisfactory amplification, all DNA amplification was carried out at a fixed annealing temperature in order to increase the efficiency of screening primer pairs for their ability to reveal comprehensive DNA fingerprints. DNA samples loaded in denaturing buffer and separated through denaturing polyacrylamide gels were found to be more informative than samples loaded in non-denaturing buffer. Staining with silver nitrate was much more sensitive than with ethidium bromide. The DAF marker technique has been developed successfully for Hevea studies. Premilinary investigations with the technique demonstrated that DAF can generate very complex and informative DNA fingerprints and promises to be useful for genetic variability, family relationship and population studies. The technique does not require sophisticated equipment, and is also more robust and reproducible than RAPD. 6 refs

  9. Chemically induced DNA hypomethylation in breast carcinoma cells detected by the amplification of intermethylated sites

    International Nuclear Information System (INIS)

    Compromised patterns of gene expression result in genomic instability, altered patterns of gene expression and tumour formation. Specifically, aberrant DNA hypermethylation in gene promoter regions leads to gene silencing, whereas global hypomethylation events can result in chromosomal instability and oncogene activation. Potential links exist between environmental agents and DNA methylation, but the destabilizing effects of environmental exposures on the DNA methylation machinery are not understood within the context of breast cancer aetiology. We assessed genome-wide changes in methylation patterns using a unique methylation profiling technique called amplification of intermethylated sites (AIMS). This method generates easily readable fingerprints that represent the investigated cell line's methylation profile, based on the differential cleavage of DNA with methylation-specific isoschisomeric restriction endonucleases. We validated this approach by demonstrating both unique and reoccurring sites of genomic hypomethylation in four breast carcinoma cell lines treated with the cytosine analogue 5-azacytidine. Comparison of treated with control samples revealed individual bands that exhibited methylation changes, and these bands were excized and cloned, and the precise genomic location individually identified. In most cases, these regions of hypomethylation coincided with susceptible target regions previously associated with chromosome breakage, rearrangement and gene amplification. Similarly, we observed that acute benzopyrene exposure is associated with altered methylation patterns in these cell lines. These results reinforce the link between environmental exposures, DNA methylation and breast cancer, and support a role for AIMS as a rapid, affordable screening method to identify environmentally induced DNA methylation changes that occur in tumourigenesis

  10. ECT2 amplification and overexpression as a new prognostic biomarker for early-stage lung adenocarcinoma.

    Science.gov (United States)

    Murata, Yoshihiko; Minami, Yuko; Iwakawa, Reika; Yokota, Jun; Usui, Shingo; Tsuta, Koji; Shiraishi, Kouya; Sakashita, Shingo; Satomi, Kaishi; Iijima, Tatsuo; Noguchi, Masayuki

    2014-04-01

    Genetic abnormality in early-stage lung adenocarcinoma was examined to search for new prognostic biomarkers. Six in situ lung adenocarcinomas and nine small but invasive adenocarcinomas were examined by array-comparative genomic hybridization, and candidate genes of interest were screened. To examine gene abnormalities, 83 cases of various types of lung carcinoma were examined by quantitative real-time genomic PCR and immunohistochemistry. The results were then verified using another set of early-stage adenocarcinomas. Array-comparative genomic hybridization indicated frequent amplification at chromosome 3q26. Of the seven genes located in this region, we focused on the epithelial cell transforming sequence 2 (ECT2) oncogene, as ECT2 amplification was detected only in invasive adenocarcinoma, and not in in situ carcinoma. Quantitative PCR and immunohistochemistry analyses also detected overexpression of ECT2 in invasive adenocarcinoma, and this was correlated with both the Ki-67 labeling index and mitotic index. In addition, it was associated with disease-free survival and overall survival of patients with lung adenocarcinoma. These results were verified using another set of early-stage adenocarcinomas resected at another hospital. Abnormality of the ECT2 gene occurs at a relatively early stage of lung adenocarcinogenesis and would be applicable as a new biomarker for prognostication of patients with lung adenocarcinoma. PMID:24484057

  11. Study of reconstruction methods for a time projection chamber with GEM gas amplification system

    International Nuclear Information System (INIS)

    A new e+e- linear collider with an energy range up to 1TeV is planned in an international collaboration: the International Linear Collider (ILC). This collider will be able to do precision measurements of the Higgs particle and of physics beyond the Standard Model. In the Large Detector Concept (LDC) - which is one proposal for a detector at the ILC - a Time Projection Chamber (TPC) is foreseen as the main tracking device. To meet the requirements on the resolution and to be able to work in the environment at the ILC, the application of new gas amplification technologies in the TPC is necessary. One option is an amplification system based on Gas Electron Multipliers (GEMs). Due to the - in comparison with older technologies - small spatial width of the signals, this technology poses new requirements on the readout structures and the reconstruction methods. In this work, the performance and the systematics of different reconstruction methods have been studied, based on data measured with a TPC prototype in high magnetic fields of up to 4T and data from a Monte Carlo simulation. The latest results of the achievable point resolution are presented and their limitations have been investigated. (orig.)

  12. Study of reconstruction methods for a time projection chamber with GEM gas amplification system

    Energy Technology Data Exchange (ETDEWEB)

    Diener, R.

    2006-12-15

    A new e{sup +}e{sup -} linear collider with an energy range up to 1TeV is planned in an international collaboration: the International Linear Collider (ILC). This collider will be able to do precision measurements of the Higgs particle and of physics beyond the Standard Model. In the Large Detector Concept (LDC) - which is one proposal for a detector at the ILC - a Time Projection Chamber (TPC) is foreseen as the main tracking device. To meet the requirements on the resolution and to be able to work in the environment at the ILC, the application of new gas amplification technologies in the TPC is necessary. One option is an amplification system based on Gas Electron Multipliers (GEMs). Due to the - in comparison with older technologies - small spatial width of the signals, this technology poses new requirements on the readout structures and the reconstruction methods. In this work, the performance and the systematics of different reconstruction methods have been studied, based on data measured with a TPC prototype in high magnetic fields of up to 4T and data from a Monte Carlo simulation. The latest results of the achievable point resolution are presented and their limitations have been investigated. (orig.)

  13. Clinical significance of fluorescence in situ hybridization for detection of hTERC gene amplification in cervical cancer and precancerous tissues cases

    Directory of Open Access Journals (Sweden)

    Shuang LIU

    2012-06-01

    Full Text Available Objective  To detect the human telomerase RNA gene (hTERC amplification in cervical lesions, and explore its clinical significance. Methods  The tissues of the cervical lesions were collected from 195 patients, including 33 of chronic cervicitis, 34 of CINⅠ, 37 of CIN Ⅱ-Ⅲ, 30 of cervical squamous cell carcinoma, and 61 of cervica1 adenocarcinoma, and abnormal hTERC was detected with amplification of fluorescence in situhybridization (FISH. The relationship between hTERC gene amplification and clinicopathological parameters was analyzed. Results  Among the 195 patients, the positive rate of hTERC gene amplification was 3.03% (1/33, 29.41% (10/34, 72.97% (27/37, 100% (30/30, 91.8% (56/61 in chronic cervicitis, CINⅠ, CIN Ⅱ-Ⅲ, cervical squamous cell carcinoma and cervica1 adenocarcinoma respectively, and the results showed that hTERC amplification rate was significantly higher in group CIN Ⅱ-Ⅲthan in group CINⅠ(P 0.05. Conclusion  Detection of gene amplification by FISH technology can be used as a means for accurate diagnosis and prediction of the histologically difficult-to-diagnose lesion and for risk assessment after treatment of cervical precancerous lesions.

  14. Rapid Diagnosis of Human Herpesvirus 6 Infection by a Novel DNA Amplification Method, Loop-Mediated Isothermal Amplification

    OpenAIRE

    Ihira, Masaru; Yoshikawa, Tetsushi; Enomoto, Yoshihiko; Akimoto, Shiho; Ohashi, Masahiro; Suga, Sadao; Nishimura, Naoko; Ozaki, Takao; Nishiyama, Yukihiro; Notomi, Tsugunori; Ohta, Yoshinori; Asano, Yoshizo

    2004-01-01

    A novel nucleic acid amplification method, termed loop-mediated isothermal amplification (LAMP), which amplifies DNA with high specificity, efficiency, and rapidity under isothermal conditions, may be a valuable tool for the rapid detection of infectious agents. LAMP was developed for human herpesvirus 6 (HHV-6), and its reliability was evaluated in this study. Although LAMP products were detected in HHV-6 B and HHV-6 A DNA, they were not detected in HHV-7 and human cytomegalovirus DNA. The s...

  15. Screen Reading Habits among University Students

    Science.gov (United States)

    Vandenhoek, Tim

    2013-01-01

    Among the numerous areas of education which have been impacted by technology, the growth of reading texts from computer screens is one of the most widespread. This trend is perhaps most evident at universities with academic journal articles increasing being stored and accessed in this format. As with any technological changes, the spread of screen…

  16. 木薯渣发酵饲料的工艺筛选%Screening of technology in cassava slag fermentation feed

    Institute of Scientific and Technical Information of China (English)

    艾必燕; 刘长忠; 陈建康; 杨扬; 米本中; 黄倩妮; 樵星芳

    2012-01-01

    Using cassava slag as the main raw material, with aspergillus, trichoderma viride and rhizopus R2 for fermentation strains, the test is to optimize cassava slag fermentation technology producing tropina feed. The appropriate conditions of cassava slag fermentation are that adding amount of liquid spawn is 3%, adding amount of nitrogen source is 10%, fermentation temperature is 37 ℃, fermentation time is 4 days. Cassava slag is a mixture, its highest level of non-nitrogen compounds is 78.7%, main component is soluble starch compounds (such as monosaccharide and starch), but its crude protein content is very low, amino acid composition is extremely uneven, it has poor effect to feed cassava slag directly, so most of the cassava slag cannot be used, which not only causes the waste of resources, but also seriously pollutes environment. Processing cassava slag into feed materials can make full use of the waste in starch industry, it is favorable to the environment protection, and it also can significantly reduce the cost of feed, improve the utilization value and economic benefits of cassava slag.%以木薯生产中产生的废渣为主要原料,以黑曲霉、绿色木霉和根霉R2为发酵菌种,优化木薯渣发酵生产菌体蛋白饲料的工艺.初步确定了木薯渣发酵的适宜条件,即液体菌种添加量为3%,氮源添加量为20%,发酵温度37℃,发酵时间为4d,经试验验证,此发酵条件下发酵饲料中粗蛋白含量较高,可达到蛋白饲料对蛋白质含量的要求.通过处理木薯渣变为动物的饲料原料,不仅可充分利用淀粉工业的废弃物,有利于环境保护,而且可显著降低饲养成本,从而提高了木薯渣的利用价值和经济效益.

  17. Reading Out Single-Molecule Digital RNA and DNA Isothermal Amplification in Nanoliter Volumes with Unmodified Camera Phones.

    Science.gov (United States)

    Rodriguez-Manzano, Jesus; Karymov, Mikhail A; Begolo, Stefano; Selck, David A; Zhukov, Dmitriy V; Jue, Erik; Ismagilov, Rustem F

    2016-03-22

    Digital single-molecule technologies are expanding diagnostic capabilities, enabling the ultrasensitive quantification of targets, such as viral load in HIV and hepatitis C infections, by directly counting single molecules. Replacing fluorescent readout with a robust visual readout that can be captured by any unmodified cell phone camera will facilitate the global distribution of diagnostic tests, including in limited-resource settings where the need is greatest. This paper describes a methodology for developing a visual readout system for digital single-molecule amplification of RNA and DNA by (i) selecting colorimetric amplification-indicator dyes that are compatible with the spectral sensitivity of standard mobile phones, and (ii) identifying an optimal ratiometric image-process for a selected dye to achieve a readout that is robust to lighting conditions and camera hardware and provides unambiguous quantitative results, even for colorblind users. We also include an analysis of the limitations of this methodology, and provide a microfluidic approach that can be applied to expand dynamic range and improve reaction performance, allowing ultrasensitive, quantitative measurements at volumes as low as 5 nL. We validate this methodology using SlipChip-based digital single-molecule isothermal amplification with λDNA as a model and hepatitis C viral RNA as a clinically relevant target. The innovative combination of isothermal amplification chemistry in the presence of a judiciously chosen indicator dye and ratiometric image processing with SlipChip technology allowed the sequence-specific visual readout of single nucleic acid molecules in nanoliter volumes with an unmodified cell phone camera. When paired with devices that integrate sample preparation and nucleic acid amplification, this hardware-agnostic approach will increase the affordability and the distribution of quantitative diagnostic and environmental tests. PMID:26900709

  18. 'Organised' cervical screening 45 years on: How consistent are organised screening practices?

    Science.gov (United States)

    Williams, Jane H; Carter, Stacy M; Rychetnik, Lucie

    2014-11-01

    Organised screening programmes have been remarkably successful in reducing incidence and mortality from cervical cancer, while opportunistic screening varies in its effectiveness. Experts recommend that cervical screening or HPV testing be carried out only in the context of an organised programme. We sought to answer the following study questions: What does it mean for a cervical screening programme to be organised? Is there a place for opportunistic screening (in an organised programme)? We reviewed 154 peer-reviewed papers on organised and opportunistic approaches to cervical screening published between 1970 and 2014 to understand how the term 'organised' is used, formally and in practice. We found that despite broad recognition of a prescriptive definition of organisation, in practice the meaning of organisation is much less clear. Our review revealed descriptions of organised programmes that differ significantly from prescribed norms and from each other, and a variety of ways that opportunistic and organised programmes intersect. We describe the breadth of the variation in cervical cancer screening programmes and examine the relationships and overlaps between organised and opportunistic screening. Implications emerging from the review include the need to better understand the breadth of organisation in practice, the drivers and impacts of opportunistic screening and the impact of opportunistic screening on population programme outcomes. Appreciation of the complexity of cervical screening programmes will benefit both screeners and women as programmes are changed to reflect a partially vaccinated population, new evidence and new technologies. PMID:25282406

  19. Learning Object Design Considerations for Small-Screen Handheld Devices

    Science.gov (United States)

    Churchill, Daniel; Hedberg, John

    2008-01-01

    The key limitation of handheld technology for the delivery of learning objects is the small screen that is available for effective display. The smallness of the screen not only adversely affects the clarity, but it also negatively impacts on the acceptance and integration of this potentially useful technology in education. Handheld devices are…

  20. Touch Screen based Speed Control of Single Phase Induction Motor

    OpenAIRE

    S. Mallika; W. Razia Sultana; Sarat Kumar Sahoo*

    2010-01-01

    This paper gives a brief idea of touch screen technology and its interfacing with a controller to control the speed of single phase induction motor. Here touch screen technology and Programmable System on Chip (PSOC) microcontroller concept is utilized which is less spaceconsumption and easy to design. The aim of this paper is to have remote sensing and speed control of an AC motor.

  1. A study of radiation hardness screening techniques of integrated circuits

    International Nuclear Information System (INIS)

    The principle and operational procedure of Integrated Circuits (ICs) screening with irradiation-and-anneal and multicomponent regression analysis are discussed. The key technology, advantages and shortcomings of the two methods are described in contrast, and some advices are given with the state-of-the-art of the screening technology

  2. Screening and analysis of candidate gene expression in asthma using microarray technology%基因芯片技术对哮喘病人相关基因的筛选和分析

    Institute of Scientific and Technical Information of China (English)

    贾少丹; 纪霞; 张为忠; 邢明青; 李靖; 王海燕; 张伟毅; 包振民

    2012-01-01

    Objective To screen different gene expressions in peripheral blood mononuclear cells between asthma patients and normal people by DNA microarray in order to provide molecular markers for early diagnosis and prevention of asthma. Methods Participants with asthma (re = 16) and healthy controls (n = 16) underwent peripheral blood collection. Monocytes were isolated using Ficoll-Paque and extracted for total RNA by QIAGEN Rneasy Kit. Then we used the Cy3 to mark the cDNA of normal people and asthma patients respectively, and used the Agilent Homo microarray chips containing 41,000 genes/ESTs to screen gene expression differentially according to the screening criteria of Ratio≥2 and Ratio≤ -2. At last, we used Gene spring software to analyze the biologic function of the candidate genes. Results By using this DNA microarray technology, 4177 candidate genes in the asthma patients were found from 34183 target genes, which expressed twice higher than those in the normal people. 19 gene expressions correlating to asthma were found with twice fold differences, as compared with the normal. Analysis showed that these differentially expressed genes mainly related to the following pathways like inflammation response, immune response, defense responses, wound responses and external stimuli. Conclusions Through screening and analysis of important candidate genes involved in asthma, we are able to investigate and explore the pathogenesis of asthma and to prevent asthma effectively in the future.%目的 利用基因芯片技术寻找哮喘病患者与正常人外周血单核细胞之间差异表达基因,拟为哮喘的早期诊断及预防提供分子标记.方法 用淋巴细胞分离液分别提取16例哮喘病患者与16例正常人外周血单核细胞,用QIAGEN Rneasy Kit提取纯化样本总RNA,并合成用荧光标记的cRNA,分别与含有41 000条基因序列的全基因芯片杂交,以基因表达倍数值≥2.0和基因表达倍数值≤-2.0为阈值来确定差异

  3. ASAP: Amplification, sequencing & annotation of plastomes

    Directory of Open Access Journals (Sweden)

    Folta Kevin M

    2005-12-01

    Full Text Available Abstract Background Availability of DNA sequence information is vital for pursuing structural, functional and comparative genomics studies in plastids. Traditionally, the first step in mining the valuable information within a chloroplast genome requires sequencing a chloroplast plasmid library or BAC clones. These activities involve complicated preparatory procedures like chloroplast DNA isolation or identification of the appropriate BAC clones to be sequenced. Rolling circle amplification (RCA is being used currently to amplify the chloroplast genome from purified chloroplast DNA and the resulting products are sheared and cloned prior to sequencing. Herein we present a universal high-throughput, rapid PCR-based technique to amplify, sequence and assemble plastid genome sequence from diverse species in a short time and at reasonable cost from total plant DNA, using the large inverted repeat region from strawberry and peach as proof of concept. The method exploits the highly conserved coding regions or intergenic regions of plastid genes. Using an informatics approach, chloroplast DNA sequence information from 5 available eudicot plastomes was aligned to identify the most conserved regions. Cognate primer pairs were then designed to generate ~1 – 1.2 kb overlapping amplicons from the inverted repeat region in 14 diverse genera. Results 100% coverage of the inverted repeat region was obtained from Arabidopsis, tobacco, orange, strawberry, peach, lettuce, tomato and Amaranthus. Over 80% coverage was obtained from distant species, including Ginkgo, loblolly pine and Equisetum. Sequence from the inverted repeat region of strawberry and peach plastome was obtained, annotated and analyzed. Additionally, a polymorphic region identified from gel electrophoresis was sequenced from tomato and Amaranthus. Sequence analysis revealed large deletions in these species relative to tobacco plastome thus exhibiting the utility of this method for structural and

  4. Somatic amplifications and deletions in genome of papillary thyroid carcinomas.

    Science.gov (United States)

    Passon, Nadia; Bregant, Elisa; Sponziello, Marialuisa; Dima, Maria; Rosignolo, Francesca; Durante, Cosimo; Celano, Marilena; Russo, Diego; Filetti, Sebastiano; Damante, Giuseppe

    2015-11-01

    Somatic gene copy number variation contributes to tumor progression. Using comparative genomic hybridization (CGH) array, the presence of genomic imbalances was evaluated in a series of 27 papillary thyroid carcinomas (PTCs). To detect only somatic imbalances, for each sample, the reference DNA was from normal thyroid tissue of the same patient. The presence of the BRAF V600E mutation was also evaluated. Both amplifications and deletions showed an uneven distribution along the entire PTC cohort; amplifications were more frequent than deletions (mean values of 17.5 and 7.2, respectively). Number of aberration events was not even among samples, the majority of them occurring only in a small fraction of PTCs. Most frequent amplifications were detected at regions 2q35, 4q26, and 4q34.1, containing FN1, PDE5A, and GALNTL6 genes, respectively. Most frequent deletions occurred at regions 6q25.2, containing OPMR1 and IPCEF1 genes and 7q14.2, containing AOAH and ELMO1 genes. Amplification of FN1 and PDE5A genomic regions was confirmed by quantitative PCR. Frequency of amplifications and deletions was in relationship with clinical features and BRAF mutation status of tumor. In fact, according to the American Joint Committee on Cancer stage and American Thyroid Association (ATA) risk classification, amplifications are more frequent in higher risk samples, while deletions tend to prevail in the lower risk tumors. Analysis of single aberrations according to the ATA risk grouping shows that amplifications containing PDE5A, GALNTL6, DHRS3, and DOCK9 genes are significantly more frequent in the intermediate/high risk group than in the low risk group. Thus, our data would indicate that analysis of somatic genome aberrations by CGH array can be useful to identify additional prognostic variables. PMID:25863487

  5. Smart Screening System (S3) In Taconite

    Energy Technology Data Exchange (ETDEWEB)

    Daryoush Allaei

    2006-09-08

    The conventional screening machines used in processing plants have had undesirable high noise and vibration levels. They also have had unsatisfactorily low screening efficiency, high energy consumption, high maintenance cost, low productivity, and poor worker safety. These conventional vibrating machines have been used in almost every processing plant. Most of the current material separation technology uses heavy and inefficient electric motors with an unbalanced rotating mass to generate the shaking. In addition to being excessively noisy, inefficient, and high-maintenance, these vibrating machines are often the bottleneck in the entire process. Furthermore, these motors, along with the vibrating machines and supporting structure, shake other machines and structures in the vicinity. The latter increases maintenance costs while reducing worker health and safety. The conventional vibrating fine screens at taconite processing plants have had the same problems as those listed above. This has resulted in lower screening efficiency, higher energy and maintenance cost, and lower productivity and workers safety concerns. The focus of this work is on the design of a high performance screening machine suitable for taconite processing plants. SmartScreens{trademark} technology uses miniaturized motors, based on smart materials, to generate the shaking. The underlying technologies are Energy Flow Control{trademark} and Vibration Control by Confinement{trademark}. These concepts are used to direct energy flow and confine energy efficiently and effectively to the screen function. The SmartScreens{trademark} technology addresses problems related to noise and vibration, screening efficiency, productivity, and maintenance cost and worker safety. Successful development of SmartScreens{trademark} technology will bring drastic changes to the screening and physical separation industry. The final designs for key components of the SmartScreens{trademark} have been developed. The key

  6. Real-Time Nucleic Acid Sequence-Based Amplification Using Molecular Beacons for Detection of Enterovirus RNA in Clinical Specimens

    OpenAIRE

    Landry, Marie L.; Garner, Robin; Ferguson, David

    2005-01-01

    Real-time nucleic acid sequence-based amplification (NASBA) using molecular beacon technology (NASBA-beacon) was compared to standard NASBA with postamplification hybridization using electrochemiluminescently labeled probes (NASBA-ECL) for detection of enteroviruses (EV) in 133 cerebrospinal fluid and 27 stool samples. NASBA-ECL and NASBA-beacon were similar in sensitivity, detecting 55 (100%) and 52 (94.5%) EV-positive samples, respectively. There were no false positives. Both NASBA assays w...

  7. Sensitive SERS detection of DNA methyltransferase by target triggering primer generation-based multiple signal amplification strategy.

    Science.gov (United States)

    Li, Ying; Yu, Chuanfeng; Han, Huixia; Zhao, Caisheng; Zhang, Xiaoru

    2016-07-15

    A novel and sensitive surface-enhanced Raman scattering (SERS) method is proposed for the assay of DNA methyltransferase (MTase) activity and evaluation of inhibitors by developing a target triggering primer generation-based multiple signal amplification strategy. By using of a duplex substrate for Dam MTase, two hairpin templates and a Raman probe, multiple signal amplification mode is achieved. Once recognized by Dam MTase, the duplex substrate can be cleaved by Dpn I endonuclease and two primers are released for triggering the multiple signal amplification reaction. Consequently, a wide dynamic range and remarkably high sensitivity are obtained under isothermal conditions. The detection limit is 2.57×10(-4)UmL(-1). This assay exhibits an excellent selectivity and is successfully applied in the screening of inhibitors for Dam MTase. In addition, this novel sensing system is potentially universal as the recognition element can be conveniently designed for other target analytes by changing the substrate of DNA MTase. PMID:26926592

  8. Rapid genome detection of Schmallenberg virus and bovine viral diarrhea virus by use of isothermal amplification methods and high-speed real-time reverse transcriptase PCR.

    Science.gov (United States)

    Aebischer, Andrea; Wernike, Kerstin; Hoffmann, Bernd; Beer, Martin

    2014-06-01

    Over the past few years, there has been an increasing demand for rapid and simple diagnostic tools that can be applied outside centralized laboratories by using transportable devices. In veterinary medicine, such mobile test systems would circumvent barriers associated with the transportation of samples and significantly reduce the time to diagnose important infectious animal diseases. Among a wide range of available technologies, high-speed real-time reverse transcriptase quantitative PCR (RT-qPCR) and the two isothermal amplification techniques loop-mediated isothermal amplification (LAMP) and recombinase polymerase amplification (RPA) represent three promising candidates for integration into mobile pen-side tests. The aim of this study was to investigate the performance of these amplification strategies and to evaluate their suitability for field application. In order to enable a valid comparison, novel pathogen-specific assays have been developed for the detection of Schmallenberg virus and bovine viral diarrhea virus. The newly developed assays were evaluated in comparison with established standard RT-qPCR using samples from experimentally or field-infected animals. Even though all assays allowed detection of the target virus in less than 30 min, major differences were revealed concerning sensitivity, specificity, robustness, testing time, and complexity of assay design. These findings indicated that the success of an assay will depend on the integrated amplification technology. Therefore, the application-specific pros and cons of each method that were identified during this study provide very valuable insights for future development and optimization of pen-side tests. PMID:24648561

  9. Transistors under stress: Mechanical stress affects amplification

    NARCIS (Netherlands)

    Hartmann, L.

    2002-01-01

    Practically every modern Intel Pentium processor main board features a temperature sensor developed at Delft University of Technology. The sensor detects when the processor starts to become too hot, and switches on a fan to cool it down. As soon as the temperature drops to an acceptable level, the f

  10. High-temperature ultrafast polariton parametric amplification in semiconductor microcavities

    Science.gov (United States)

    Saba, M.; Ciuti, C.; Bloch, J.; Thierry-Mieg, V.; André, R.; Dang, Le Si; Kundermann, S.; Mura, A.; Bongiovanni, G.; Staehli, J. L.; Deveaud, B.

    2001-12-01

    Cavity polaritons, the elementary optical excitations of semiconductor microcavities, may be understood as a superposition of excitons and cavity photons. Owing to their composite nature, these bosonic particles have a distinct optical response, at the same time very fast and highly nonlinear. Very efficient light amplification due to polariton-polariton parametric scattering has recently been reported in semiconductor microcavities at liquid-helium temperatures. Here we demonstrate polariton parametric amplification up to 120K in GaAlAs-based microcavities and up to 220K in CdTe-based microcavities. We show that the cut-off temperature for the amplification is ultimately determined by the binding energy of the exciton. A 5-µm-thick planar microcavity can amplify a weak light pulse more than 5,000 times. The effective gain coefficient of an equivalent homogeneous medium would be 107cm-1. The subpicosecond duration and high efficiency of the amplification could be exploited for high-repetition all-optical microscopic switches and amplifiers. 105 polaritons occupy the same quantum state during the amplification, realizing a dynamical condensate of strongly interacting bosons which can be studied at high temperature.

  11. Problems encountered when defining Arctic amplification as a ratio

    Science.gov (United States)

    Hind, Alistair; Zhang, Qiong; Brattström, Gudrun

    2016-07-01

    In climate change science the term ‘Arctic amplification’ has become synonymous with an estimation of the ratio of a change in Arctic temperatures compared with a broader reference change under the same period, usually in global temperatures. Here, it is shown that this definition of Arctic amplification comes with a suite of difficulties related to the statistical properties of the ratio estimator itself. Most problematic is the complexity of categorizing uncertainty in Arctic amplification when the global, or reference, change in temperature is close to 0 over a period of interest, in which case it may be impossible to set bounds on this uncertainty. An important conceptual distinction is made between the ‘Ratio of Means’ and ‘Mean Ratio’ approaches to defining a ratio estimate of Arctic amplification, as they do not only possess different uncertainty properties regarding the amplification factor, but are also demonstrated to ask different scientific questions. Uncertainty in the estimated range of the Arctic amplification factor using the latest global climate models and climate forcing scenarios is expanded upon and shown to be greater than previously demonstrated for future climate projections, particularly using forcing scenarios with lower concentrations of greenhouse gases.

  12. Adaptive base-isolation of civil structures using variable amplification

    Institute of Scientific and Technical Information of China (English)

    Kenneth K. Walsh; Makola M. Abdullah

    2006-01-01

    Semi-active dampers are used in base-isolation to reduce the seismic response of civil engineering structures.In the present study, a new semi-active damping system using variable amplification will be investigated for adaptive baseisolation. It uses a novel variable amplification device (VAD) connected in series with a passive damper. The VAD is capable of producing multiple amplification factors, each corresponding to a different amplification state. Forces from the damper are amplified to the structure according to the current amplification state, which is selected via a semi-active control algorithm specifically tailored to the system's unique damping characteristics. To demonstrate the effectiveness of the VAD-damper system for adaptive base-isolation, numerical simulations are conducted for three and seven-story base-isolated buildings subject to both far and near-field ground motions. The results indicate that the system can achieve significant reductions in response compared to the base-isolated buildings with no damper. The proposed system is also found to perform well compared to a typical semi-active damper.

  13. Prostate cancer screenings

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000846.htm Prostate cancer screenings To use the sharing features on this ... Intern Med . 2011;155(11):762-71. National Cancer Institute. Prostate Cancer Screening -- for health professionals. Revised April 2, ...

  14. Screening for hypertension.

    OpenAIRE

    Tomson, P R V

    1983-01-01

    In an open access screening campaign for hypertension lasting six weeks 6259 individuals were screened with a Vita-Stat blood pressure computer and an estimated 4.2% to 5.4% of new cases were detected.

  15. Breast cancer screenings

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000837.htm Breast cancer screenings To use the sharing features on this page, please enable JavaScript. Breast cancer screenings can help find breast cancer early, before ...

  16. Colon cancer screening

    Science.gov (United States)

    ... screening; Virtual colonoscopy - screening; Fecal immunochemical test; Stool DNA test; sDNA test ... called the fecal immunochemical test (FIT) and stool DNA test (sDNA). Sigmoidoscopy : This test uses a small flexible ...

  17. Screening for Prostate Cancer

    Science.gov (United States)

    ... of Internal Medicine Summaries for Patients Screening for Prostate Cancer: A Guidance Statement From the Clinical Guidelines Committee ... Physicians The full report is titled “Screening for Prostate Cancer: A Guidance Statement From the Clinical Guidelines Committee ...

  18. Human Papillomavirus (HPV) Screening

    Science.gov (United States)

    ... Diseases HPV-Associated Cancers Gynecologic Cancers Redirect CDC - Screening Recommend on Facebook Tweet Share Compartir You are being redirected to the HPV Cancer Screening page. Please update your bookmarks to the link ...

  19. Prostate Cancer Screening

    Science.gov (United States)

    ... man's bladder that produces fluid for semen. Cancer screening is looking for cancer before you have any ... be easier to treat. There is no standard screening test for prostate cancer. Researchers are studying different ...

  20. Screen Practice in Curating

    DEFF Research Database (Denmark)

    Toft, Tanya Søndergaard

    2014-01-01

    During the past one and a half decade, a curatorial orientation towards "screen practice" has expanded the moving image and digital art into the public domain, exploring alternative artistic uses of the screen. The emergence of urban LED screens in the late 1990s provided a new venue that allowed...... for digital art to expand into public space. It also offered a political point of departure, inviting for confrontation with the Spectacle and with the politics and ideology of the screen as a mass communication medium that instrumentalized spectator positions. In this article I propose that screen...... practice in curating has emerged from a critical discourse in response to a particular "screen topos", which has relied on a Foucauldian, apparatus-theoretical mechanism of the screen as a broadcasting medium of mass entertainment. This topos, I argue, has transferred the dispositif of the screen apparatus...

  1. Screening for Ovarian Cancer

    Science.gov (United States)

    Understanding Task Force Recommendations Screening for Ovarian Cancer The U.S. Preventive Services Task Force (Task Force) has issued a final recommendation on Screening for Ovarian Cancer . This recommendation is ...

  2. Cervical Cancer Screening

    Science.gov (United States)

    ... Cancer found early may be easier to treat. Cervical cancer screening is usually part of a woman's health ... may do more tests, such as a biopsy. Cervical cancer screening has risks. The results can sometimes be ...

  3. Screening Tests and Vaccines

    Science.gov (United States)

    ... Contact Us Text size | Print | Screening Tests and Vaccines This information in Spanish ( en español ) Getting important screening tests and vaccines can save your life. Check this section of ...

  4. Video Screen Capture Basics

    Science.gov (United States)

    Dunbar, Laura

    2014-01-01

    This article is an introduction to video screen capture. Basic information of two software programs, QuickTime for Mac and BlueBerry Flashback Express for PC, are also discussed. Practical applications for video screen capture are given.

  5. Development of an in vitro compartmentalization screen for high-throughput directed evolution of [FeFe] hydrogenases.

    Directory of Open Access Journals (Sweden)

    James A Stapleton

    Full Text Available BACKGROUND: [FeFe] hydrogenase enzymes catalyze the formation and dissociation of molecular hydrogen with the help of a complex prosthetic group composed of common elements. The development of energy conversion technologies based on these renewable catalysts has been hindered by their extreme oxygen sensitivity. Attempts to improve the enzymes by directed evolution have failed for want of a screening platform capable of throughputs high enough to adequately sample heavily mutated DNA libraries. In vitro compartmentalization (IVC is a powerful method capable of screening for multiple-turnover enzymatic activity at very high throughputs. Recent advances have allowed [FeFe] hydrogenases to be expressed and activated in the cell-free protein synthesis reactions on which IVC is based; however, IVC is a demanding technique with which many enzymes have proven incompatible. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe an extremely high-throughput IVC screen for oxygen-tolerant [FeFe] hydrogenases. We demonstrate that the [FeFe] hydrogenase CpI can be expressed and activated within emulsion droplets, and identify a fluorogenic substrate that links activity after oxygen exposure to the generation of a fluorescent signal. We present a screening protocol in which attachment of mutant genes and the proteins they encode to the surfaces of microbeads is followed by three separate emulsion steps for amplification, expression, and evaluation of hydrogenase mutants. We show that beads displaying active hydrogenase can be isolated by fluorescence-activated cell-sorting, and we use the method to enrich such beads from a mock library. CONCLUSIONS/SIGNIFICANCE: [FeFe] hydrogenases are the most complex enzymes to be produced by cell-free protein synthesis, and the most challenging targets to which IVC has yet been applied. The technique described here is an enabling step towards the development of biocatalysts for a biological hydrogen economy.

  6. Modeling Loss Amplification After Devastating Disasters

    Science.gov (United States)

    Boissonnade, A. C.; Muir Wood, R.

    2008-05-01

    With the catastrophic events that occurred in 2004 and 2005 came the realization that Catastrophic (Cat) loss models were not properly modeling insured losses and their associated uncertainty. One reason was that major catastrophes were generally characterized by losses caused by the primary initiating events. Such approaches are not adequate when losses can result from the compounded impacts of scenarios of secondary cascading events (physical, economic, social and political) that can have much larger impacts than those due to the primary events themselves. Situations where more and more cascading events can occur will result in different outcomes, some leading to extreme loss events, generally referred as Super Cats. These situations occurred in December 2004 with the Sumatra earthquake and tsunami and in August 2005 with hurricane Katrina and resulting New Orleans flooding. A review of historical events shows that these events are not exceptions. Modeling such scenarios adds new levels of complexity and different perspectives in the understanding of characterizing and assessing impacts of catastrophic events. Modeling economic consequences of extreme events can be improved by developing scenarios of cascades of secondary events triggered by the primary event(s). The likelihood of each scenario should be modeled, along with the hazards of primary and secondary events and resulting losses with their impacts to the different stakeholders. In addition, it is also important to model the impacts of the hazards on the infrastructure and the resulting disruption to the residents and the local economy because these can result in additional losses. This paper describes current work with the goals of better modeling the full economic impacts from catastrophic events, and of a more comprehensive treatment of uncertainty. We will present approaches for modeling loss amplification that account for all the ways in which the cost incurred for a certain level of damage due to a

  7. A 6.2 mW 0.024 mm2 fully-passive RF downconverter with 12 dB gain enhancement using MOS parametric amplification

    DEFF Research Database (Denmark)

    Custódio, J. R.; Bastos, I.; Oliveira, L. B.;

    2013-01-01

    This paper describes a fully-passive discrete-time switched-capacitor RF downconverter with an on-chip oscillator, that combines quadrature mixing and harmonic rejection, designed in a 130 nm digital CMOS technology. By using MOS capacitors (varactors) to perform parametric amplification, it is...

  8. New Perspectives on Assessing Amplification Effects

    OpenAIRE

    Souza, Pamela E.; Tremblay, Kelly L.

    2006-01-01

    Clinicians have long been aware of the range of performance variability with hearing aids. Despite improvements in technology, there remain many instances of well-selected and appropriately fitted hearing aids whereby the user reports minimal improvement in speech understanding. This review presents a multistage framework for understanding how a hearing aid affects performance. Six stages are considered: (1) acoustic content of the signal, (2) modification of the signal by the hearing aid, (3...

  9. Radioactive wastes and the social amplification of risk

    International Nuclear Information System (INIS)

    A significant problem in radioactive waste facility siting is that apparent small risks or minor risks events produce substantial public concern and social impacts. The reasons for this difference in public health and societal impacts is not well understood. This paper explores the issues involved in the social amplification of risk, using the risk associated with site characterization as the example. Noteworthy as sources of amplification are the information flow associated with risks and risk events including the large volume of information, the extent of dispute, and misinformation and rumor. Such information passes through the mass media and interpersonal networks. The major mechanisms involved in risk amplifications are discussed and their likely impacts on society described

  10. Discovery of a photoresponse amplification mechanism in compensated PN junctions

    International Nuclear Information System (INIS)

    We report the experimental evidence of uncovering a photoresponse amplification mechanism in heavily doped, partially compensated silicon p-n junctions under very low bias voltage. We show that the observed photocurrent gain occurs at a bias that is more than an order of magnitude below the threshold voltage for conventional impact ionization. Moreover, contrary to the case of avalanche detectors and p-i-n diodes, the amplified photoresponse is enhanced rather than suppressed with increasing temperature. These distinctive characteristics lead us to hypothesize that the inelastic scattering between energetic electrons (holes) and the ionized impurities in the depletion and charge neutral regions of the p-n junction in a cyclic manner plays a significant role in the amplification process. Such an internal signal amplification mechanism, which occurs at much lower bias than impact ionization and favors room temperature over cryogenic temperature, makes it promising for practical device applications

  11. Amplification of spin waves by the spin Seebeck effect

    Science.gov (United States)

    Padrón-Hernández, E.; Azevedo, A.; Rezende, S. M.

    2012-04-01

    We observe amplification of spin-wave packets propagating along a film of single-crystal yttrium iron garnet (YIG) subject to a transverse temperature gradient. The spin waves are excited and detected with standard techniques used to study volume or surface magnetostatic waves in the 1-2 GHz frequency range. Amplification gains larger than 20 are observed in a YIG film heated by a current of 20 mA in a Pt layer in a simple YIG/Pt bilayer. The amplification is attributed to the action of a spin-transfer thermal torque acting on the magnetization that opposes the relaxation and which is created by spin currents generated through the spin Seebeck effect. The experimental data are interpreted with a spin-wave model.

  12. Chemical amplification of magnetic field effects relevant to avian magnetoreception

    Science.gov (United States)

    Kattnig, Daniel R.; Evans, Emrys W.; Déjean, Victoire; Dodson, Charlotte A.; Wallace, Mark I.; MacKenzie, Stuart R.; Timmel, Christiane R.; Hore, P. J.

    2016-04-01

    Magnetic fields as weak as the Earth's can change the yields of radical pair reactions even though the energies involved are orders of magnitude smaller than the thermal energy, kBT, at room temperature. Proposed as the source of the light-dependent magnetic compass in migratory birds, the radical pair mechanism is thought to operate in cryptochrome flavoproteins in the retina. Here we demonstrate that the primary magnetic field effect on flavin photoreactions can be amplified chemically by slow radical termination reactions under conditions of continuous photoexcitation. The nature and origin of the amplification are revealed by studies of the intermolecular flavin-tryptophan and flavin-ascorbic acid photocycles and the closely related intramolecular flavin-tryptophan radical pair in cryptochrome. Amplification factors of up to 5.6 were observed for magnetic fields weaker than 1 mT. Substantial chemical amplification could have a significant impact on the viability of a cryptochrome-based magnetic compass sensor.

  13. 微柱凝胶技术检测血型不规则抗体的临床应用%The clinical application of irregular antibody screening by microtube gel technology

    Institute of Scientific and Technical Information of China (English)

    宁芳; 粟明丽; 邓梅英

    2014-01-01

    目的:分析微柱凝胶技术对输血患者进行血型不规则抗体的筛查情况及临床应用。方法对2010年1月~2013年12月于桂林医学院附属医院输血患者29208例进行不规则抗体检测,统计分析阳性结果,鉴定阳性抗体的特异性。结果29208例患者中,检出不规则抗体阳性者90例,阳性率为0.31%。特异性抗体以Rh血型系统居多,抗-D抗体占2.22%、抗-E抗体占21.11%、抗-Ec抗体占11.11%;MNSs系统抗-Mur抗体11例(12.22%)、抗-M抗体7例(7.78%);Lewis系统抗-Lea抗体占8.89%;冷抗体占7.78%。非特异性抗体占13.33%。结论输血前对患者血液进行血型不规则抗体筛查并鉴定其特异性,输注不含相应抗原的血液,避免溶血性输血反应的发生,对确保输血安全有效有重要的临床意义。%Objective To analyze the situation and clinical application of microtube gel technology (MGT) in the irreg-ular antibody screening of patients before blood transfusion. Methods 29 208 patients from January 2010 to December 2013 in Affiliated Hospital of Guilin Medical University were screened for irregular antibody. The results were statisti-cal analyzed to identify the specificity of positive antibody. Results Among 29 208 patients, there were 90 cases with irregular antibody, the positive rate was 0.31%. Rh blood type system accounted for the most part of the specific anti-bodies: 2.22% for anti-D antibody, 21.11% of anti-E antibody and 11.11% of anti-Ec antibody. 11 cases of Anti-Mur of MNSs system accounted for 12.22% of the total and 7 cases of anti-M antibody accounted for 7.78%. 8.89% was for Anti-Lea antibody in Lewis system and 7.78% for cold antibody. And the non-specific antibodies accounted for 13.33%. Conclusion Irregular antibody should be screened and its specificity should also be identified before transfu-sion. To transfuse the blood without the corresponding antibodies can prevent transfusional hemolytic reaction, which is

  14. 核酸检测技术在安徽血液中心血液筛检中的应用分析%Application of nucleic acid testing(NET)technology for blood screening in Anhui blood center

    Institute of Scientific and Technical Information of China (English)

    吕蓉; 盛琪琪; 赵阳; 刘忠

    2014-01-01

    目的:探讨核酸检测(NAT)技术用于血液筛查的意义。方法采用实时荧光定量PCR和转录介导扩增(TMA)两种方法分别对我站298份及6737份无偿献血者标本进行单人份病毒核酸检测(ID-NAT),并将两种核酸检测方法的结果与ELASA检测结果进行对比分析。结果两种方法均存在相当比例的ELASA(+)、NAT(-)结果,德国GFE核酸检测试剂HBV、HCV阳性检出率低于美国诺华的ID-TMA检测试剂。经TMA-NAT检测发现本地区2次ELASA血清学方法进行血液病毒筛查HBV的残余风险为万分之4.8。本次研究没有发现HCV和HIV的血清学漏检。诺华ID-NAT核酸检测试剂存在一定的假阳性。结论核酸检测对于降低输血传播传染病的风险起到了非常重要的作用;诺华TIGRIS核酸检测体系适用于献血者血液病毒的筛查。%Objective To investigate the signification of nucleic acid testing (NAT)technology in blood screening.Methods The 298 and 6737 blood donors'samples were detected with individual donation NAT(ID-NAT)by using real-time PCR and TMA,respectively. The results from two nucleic acid testing were analyzed compared with those from ELISA.Results Both methods contained a considerable proportion of results in ELASA(+)and NAT(-).The positive detection rate of the GFE NAT reagents in HBV and HCV was lower than the detection reagents of Novartis ID-TMA.Through TMA-NAT detection we find that the residual rate was 4.8 in a million by using twice serolo-gy method of ELASA which was used to screen the blood of HBV in our area.Undetected samples between HCV and HIV were not found by using serology method in this research.There was a false positive in the detection reagents of Novartis ID-NAT.Conclusion NAT could play an important role in decreasing the risk of blood transfusion.Novartis TIGRIS system of NAT is appropriate for screening the virus of the do-nors'blood .

  15. Screening for colorectal cancer.

    Science.gov (United States)

    He, Jin; Efron, Jonathan E

    2011-01-01

    March is national colorectal cancer awareness month. It is estimated that as many as 60% of colorectal cancer deaths could be prevented if all men and women aged 50 years or older were screened routinely. In 2000, Katie Couric's televised colonoscopy led to a 20% increase in screening colonoscopies across America, a stunning rise called the "Katie Couric Effect". This event demonstrated how celebrity endorsement affects health behavior. Currently, discussion is ongoing about the optimal strategy for CRC screening, particularly the costs of screening colonoscopy. The current CRC screening guidelines are summarized in Table 2. Debates over the optimum CRC screening test continue in the face of evidence that 22 million Americans aged 50 to 75 years are not screened for CRC by any modality and 25,000 of those lives may have been saved if they had been screened for CRC. It is clear that improving screening rates and reducing disparities in underscreened communities and population subgroups could further reduce colorectal cancer morbidity and mortality. National Institutes of Health consensus identified the following priority areas to enhance the use and quality of colorectal cancer screening: Eliminate financial barriers to colorectal cancer screening and appropriate follow-up of positive results of colorectal cancer screening. Develop systems to ensure the high quality of colorectal cancer screening programs. Conduct studies to determine the comparative effectiveness of the various colorectal cancer screening methods in usual practice settings. Encouraging population adherence to screening tests and allowing patients to select the tests they prefer may do more good (as long as they choose something) than whatever procedure is chosen by the medical profession as the preferred test. PMID:21954677

  16. Screening vs. signaling in technology licensing

    OpenAIRE

    Manel Antelo

    2010-01-01

    A patent holder owning a two-period lasting innovation is unable to push it into the market, so it is licensed to a downstream user with production capabilities to market it. The production cost of this firm can be low or high, but the patent holder has only a prior on this fact

  17. Novel degenerate PCR method for whole genome amplification applied to Peru Margin (ODP Leg 201 subsurface samples

    Directory of Open Access Journals (Sweden)

    Amanda eMartino

    2012-01-01

    Full Text Available A degenerate PCR-based method of whole-genome amplification, designed to work fluidly with 454 sequencing technology, was developed and tested for use on deep marine subsurface DNA samples. The method, which we have called Random Amplification Metagenomic PCR (RAMP, involves the use of specific primers from Roche 454 amplicon sequencing, modified by the addition of a degenerate region at the 3’ end. It utilizes a PCR reaction, which resulted in no amplification from blanks, even after 50 cycles of PCR. After efforts to optimize experimental conditions, the method was tested with DNA extracted from cultured E. coli cells, and genome coverage was estimated after sequencing on three different occasions. Coverage did not vary greatly with the different experimental conditions tested, and was around 62% with a sequencing effort equivalent to a theoretical genome coverage of 14.10X. The GC content of the sequenced amplification product was within 2% of the predicted values for this strain of E. coli. The method was also applied to DNA extracted from marine subsurface samples from ODP Leg 201 site 1229 (Peru Margin, and results of a taxonomic analysis revealed microbial communities dominated by Proteobacteria, Chloroflexi, Firmicutes, Euryarchaeota, and Crenarchaeota, among others. These results were similar to those obtained previously for those samples; however, variations in the proportions of taxa show that community analysis can be sensitive to both the amplification technique used and the method of assigning sequences to taxonomic groups. Overall, we find that RAMP represents a valid methodology for amplifying metagenomes from low biomass samples.

  18. Methods for microbial DNA extraction from soil for PCR amplification.

    Science.gov (United States)

    Yeates, C; Gillings, M R; Davison, A D; Altavilla, N; Veal, D A

    1998-05-14

    Amplification of DNA from soil is often inhibited by co-purified contaminants. A rapid, inexpensive, large-scale DNA extraction method involving minimal purification has been developed that is applicable to various soil types (1). DNA is also suitable for PCR amplification using various DNA targets. DNA was extracted from 100g of soil using direct lysis with glass beads and SDS followed by potassium acetate precipitation, polyethylene glycol precipitation, phenol extraction and isopropanol precipitation. This method was compared to other DNA extraction methods with regard to DNA purity and size. PMID:12734590

  19. Raman amplification in the broken-wave regime

    CERN Document Server

    Farmer, John P

    2015-01-01

    In regimes far beyond the wavebreaking theshold of Raman amplification, we show that significant amplifcation can occur after the onset of wavebreaking, before phase mixing destroys the coupling between pump and probe. The amplification efficiency in this regime is therefore strongly dependent on the energy-transfer rate when wavebreaking occurs, and is, as such, sensitive to both the probe amplitude and profile. In order to access the higher-efficiency broken-wave regime, a short, intense probe is required. Parameter scans show the marked difference in behaviour compared to below wavebreaking, where longer, more energetic pulses lead to improved efficiencies.

  20. Methods for microbial DNA extraction from soil for PCR amplification

    Directory of Open Access Journals (Sweden)

    Yeates C

    1998-01-01

    Full Text Available Amplification of DNA from soil is often inhibited by co-purified contaminants. A rapid, inexpensive, large-scale DNA extraction method involving minimal purification has been developed that is applicable to various soil types (1. DNA is also suitable for PCR amplification using various DNA targets. DNA was extracted from 100g of soil using direct lysis with glass beads and SDS followed by potassium acetate precipitation, polyethylene glycol precipitation, phenol extraction and isopropanol precipitation. This method was compared to other DNA extraction methods with regard to DNA purity and size.

  1. Symmetry between absorption and amplification in disordered media

    International Nuclear Information System (INIS)

    We address the issue of whether amplification, like absorption, suppresses wave transmission at large gain, as has been claimed in previous studies of wave propagation in active random media. A closer examination reveals that the paradoxical symmetry between absorption and amplification is an artifact of unphysical solutions from the time-independent wave equation. Solutions from the time-dependent equation demonstrate clearly that when gain is above the threshold, the amplitude of both the transmitted and the reflected wave actually increases with time, apparently without bound. The implications of the current finding is discussed. copyright 1999 The American Physical Society

  2. Influence of environmental noise on the weak value amplification

    Science.gov (United States)

    Zhu, Xuannmin; Zhang, Yu-Xiang

    2016-08-01

    Quantum systems are always disturbed by environmental noise. We have investigated the influence of the environmental noise on the amplification in weak measurements. Three typical quantum noise processes are discussed in this article. The maximum expectation values of the observables of the measuring device decrease sharply with the strength of the depolarizing and phase damping channels, while the amplification effect of weak measurement is immune to the amplitude damping noise. To obtain significantly amplified signals, we must ensure that the preselection quantum systems are kept away from the depolarizing and phase damping processes.

  3. Ultra-broad bandwidth parametric amplification at degeneracy.

    Science.gov (United States)

    Limpert, J; Aguergaray, C; Montant, S; Manek-Hönninger, I; Petit, S; Descamps, D; Cormier, E; Salin, F

    2005-09-19

    We report on a novel approach of ultra-broad bandwidth parametric amplification around degeneracy. A bandwidth of up to 400 nm centered around 800 nm is amplified in a BBO crystal by using chirped pump pulses with a bandwitdth as broad as 10 nm. A supercontinuum signal is generated in a microstructured fiber, having to first order a quadratic chirp, which is necessary to ensure temporal overlap of the interacting waves over this broad bandwidth. Furthermore, we discuss the potential of this approach for an octave-spanning parametric amplification. PMID:19498762

  4. Influence of environmental noise on the weak value amplification

    Science.gov (United States)

    Zhu, Xuannmin; Zhang, Yu-Xiang

    2016-05-01

    Quantum systems are always disturbed by environmental noise. We have investigated the influence of the environmental noise on the amplification in weak measurements. Three typical quantum noise processes are discussed in this article. The maximum expectation values of the observables of the measuring device decrease sharply with the strength of the depolarizing and phase damping channels, while the amplification effect of weak measurement is immune to the amplitude damping noise. To obtain significantly amplified signals, we must ensure that the preselection quantum systems are kept away from the depolarizing and phase damping processes.

  5. Femtosecond pulse amplification in cladding-pumped fibers

    OpenAIRE

    Minelly, J. D.; Galvanauskas, A.; Fermann, M. E.; Harter, D.; Caplen, J.E.; Chen, Z.J.; Payne, D. N.

    1995-01-01

    Femtosecond pulse amplification in a cladding-pumped fiber amplifier is demonstrated for the first time to our knowledge. Using a cladding-pumped erbium-doped fiber power amplifier and a passively mode-locked fiber seed oscillator in conjunction with an all-fiber chirped-pulse amplification system, we obtain 380-fs near-bandwidth-limited pulses with an average power of 260 mW. The pulse repetition rate is varied between 5 and 50 MHz, and pulse energies as high as 20 nJ are generated.

  6. Divided-pulse amplification to the joule level.

    Science.gov (United States)

    Webb, Benjamin; Azim, Ahmad; Bodnar, Nathan; Chini, Michael; Shah, Lawrence; Richardson, Martin

    2016-07-01

    Divided-pulse amplification (DPA) has proven to be a valuable tool in scaling the peak power of diode-pumped ytterbium-doped amplifiers to beyond the single-pulse threshold for parasitic nonlinear effects. DPA enables the amplification of picosecond pulses in solid-state amplifiers with limited bandwidth beyond the single-pulse damage threshold. In this Letter, we demonstrate DPA of picosecond pulses in a flashlamp-pumped Nd:YAG amplifier for the first time, to the best of our knowledge, yielding a combined pulse energy of 167 mJ. PMID:27367113

  7. Development of a loop-mediated isothermal amplification assay for the detection of Streptococcus agalactiae in bovine milk.

    Science.gov (United States)

    Bosward, Katrina L; House, John K; Deveridge, Amber; Mathews, Karen; Sheehy, Paul A

    2016-03-01

    Streptococcus agalactiae is a well-characterized bovine mastitis pathogen that is known to be highly contagious and capable of spreading rapidly in affected dairy herds. Loop-mediated isothermal amplification (LAMP) is a novel molecular diagnostic method that has the capability to provide rapid, cost-effective screening for pathogens to support on-farm disease control and eradication programs. In the current study, a LAMP test was developed to detect S. agalactiae in milk. The assay was validated on a bank of existing clinical mastitis milk samples that had previously been identified as S. agalactiae positive via traditional microbiological culture techniques and PCR. The LAMP assay was conducted on bacterial colonies and DNA extracted from milk in tube- and plate-based formats using multiple detection platforms. The 1-h assay conducted at 64 °C exhibited repeatability (coefficient of variation) of 2.07% (tube) and 8.3% (plate), sensitivity to ~20 pg of extracted DNA/reaction, and specificity against a panel of known bacterial mastitis pathogens. Of the 109 known S. agalactiae isolates assessed by LAMP directly from bacterial cells in culture, 108 were identified as positive, in accordance with PCR analysis. The LAMP analysis from the corresponding milk samples indicated that 104 of these milks exhibited a positive amplification curve. Although exhibiting some limitations, this assay provides an opportunity for rapid screening of milk samples to facilitate on-farm management of this pathogen. PMID:26778303

  8. Image analysis in high-content screening.

    Science.gov (United States)

    Niederlein, Antje; Meyenhofer, Felix; White, Daniel; Bickle, Marc

    2009-11-01

    The field of High Content Screening (HCS) has evolved from a technology used exclusively by the pharmaceutical industry for secondary drug screening, to a technology used for primary drug screening and basic research in academia. The size and the complexity of the screens have been steadily increasing. This is reflected in the fact that the major challenges facing the field at the present are data mining and data storage due to the large amount of data generated during HCS. On the one hand, technological progress of fully automated image acquisition platforms, and on the other hand advances in the field of automated image analysis have made this technology more powerful and more accessible to less specialized users. Image analysis solutions for many biological problems exist and more are being developed to increase both the quality and the quantity of data extracted from the images acquired during the screens. We highlight in this review some of the major challenges facing automatic high throughput image analysis and present some of the software solutions available on the market or from academic open source solutions. PMID:19531001

  9. The Macromolecular Route to Chiral Amplification.

    Science.gov (United States)

    Green; Park; Sato; Teramoto; Lifson; Selinger; Selinger

    1999-11-01

    Cooperative phenomena, described by one-dimensional statistical physical methods, are observed between the enantiomeric characteristics of monomeric materials and the polymers they produce. The effect of minute energies associated with this amplified chirality, although currently not interpretable, can be easily measured. Nonlinear relationships between enantiomeric excess or enantiomeric content and polymer properties may offer the possibility of developing chiral catalysts and chiral chromatographic materials in which the burden of large enantiomeric excess or content may be considerably alleviated. New approaches to information and sensor technology may become possible. PMID:10556885

  10. Transistors under stress: Mechanical stress affects amplification

    OpenAIRE

    L. Hartmann

    2002-01-01

    Practically every modern Intel Pentium processor main board features a temperature sensor developed at Delft University of Technology. The sensor detects when the processor starts to become too hot, and switches on a fan to cool it down. As soon as the temperature drops to an acceptable level, the fan is switched off. The temperature sensor was developed by Dr. Anton Bakker, who in April 2000 was awarded his doctorate for his research on this subject (see also Delft Outlook 97.1), and subsequ...

  11. PKS and NRPS gene clusters from microbial symbiont cells of marine sponges by whole genome amplification.

    Science.gov (United States)

    Siegl, Alexander; Hentschel, Ute

    2010-08-01

    Whole genome amplification (WGA) approaches provide genomic information on single microbial cells and hold great promise for the field of environmental microbiology. Here, the microbial consortia of the marine sponge Aplysina aerophoba were sorted by fluorescence-activated cell sorting (FACS) and then subjected to WGA. A cosmid library was constructed from the WGA product of a sample containing two bacterial cells, one a member of the candidate phylum Poribacteria and one of a sponge-specific clade of Chloroflexi. Library screening led to the genomic characterization of three cosmid clones, encoding a polyketide synthase (PKS), a non-ribosomal peptide synthetase (NRPS) and the Chloroflexi 16S rRNA gene. PCR screening of WGA products from additional, FACS-sorted single bacterial symbiont cells supports the assignment of the Sup-PKS gene to the Poribacteria and the novel NRPS gene to the Chloroflexi. This promising single-cell genomics approach has permitted cloning of entire gene clusters from single microbial cells of known phylogenetic origin and thus provides a sought-after link between phylogeny and function. PMID:23766222

  12. Risks of Cervical Cancer Screening

    Science.gov (United States)

    ... Treatment Cervical Cancer Prevention Cervical Cancer Screening Research Cervical Cancer Screening (PDQ®)–Patient Version What is screening? Screening ... These are called diagnostic tests . General Information About Cervical Cancer Key Points Cervical cancer is a disease in ...

  13. The Development of Screen Literacy and Predictions for the Future

    OpenAIRE

    Erol DURAN; DOLAYLAR ÖZKUL, İncinur

    2015-01-01

    The screens, encountered in all areas of our lives, has led to changes interms of reading environment. From an early age accustomed to reading on paper an wrting to screen, was replaced by reading from screen and wrting to screen. This study aims to explain the development of the screen, which will continue to exist with a major development in emerging and changing technology in the future and are intended to provide estimates of the future. In this study, the data collected by scanning the l...

  14. New Front End Technology

    Energy Technology Data Exchange (ETDEWEB)

    Pennington, D; Jovanovic, I; Comaskey, B J

    2001-02-01

    The next generation of Petawatt class lasers will require the development of new laser technology. Optical parametric chirped pulse amplification (OPCPA) holds a potential to increase the peak power level to >10 PW with existing grating technology through ultrashort pulses. Furthermore, by utilizing a new type of front-end system based on optical parametric amplification, pulses can be produced with substantially higher contrast than with Ti:sapphire regenerative amplifier technology. We performed extensive study of OPCPA using a single crystal-based OPA. We developed a replacement for Ti:sapphire regenerative amplifier for high peak power lasers based on OPCPA, with an output of 30 mJ, at 10 Hz repetition rate and 16.5 nm spectral bandwidth. We developed a 3D numerical model for OPCPA and we performed a theoretical study of influences of pump laser beam quality on optical parametric amplification. Our results indicate that OPCPA represents a valid replacement for Ti:sapphire in the front end of high energy short pulse lasers.

  15. Highly efficient amplification of chronic wasting disease agent by protein misfolding cyclic amplification with beads (PMCAb.

    Directory of Open Access Journals (Sweden)

    Chad J Johnson

    Full Text Available Protein misfolding cyclic amplification (PMCA has emerged as an important technique for detecting low levels of pathogenic prion protein in biological samples. The method exploits the ability of the pathogenic prion protein to convert the normal prion protein to a proteinase K-resistant conformation. Inclusion of Teflon® beads in the PMCA reaction (PMCAb has been previously shown to increase the sensitivity and robustness of detection for the 263 K and SSLOW strains of hamster-adapted prions. Here, we demonstrate that PMCAb with saponin dramatically increases the sensitivity of detection for chronic wasting disease (CWD agent without compromising the specificity of the assay (i.e., no false positive results. Addition of Teflon® beads increased the robustness of the PMCA reaction, resulting in a decrease in the variability of PMCA results. Three rounds of serial PMCAb allowed detection of CWD agent from a 6.7 × 10(-13 dilution of 10% brain homogenate (1.3 fg of source brain. Titration of the same brain homogenate in transgenic mice expressing cervid prion protein (Tg(CerPrP1536(+/- mice allowed detection of CWD agent from the 10(-6 dilution of 10% brain homogenate. PMCAb is, thus, more sensitive than bioassay in transgenic mice by a factor exceeding 10(5. Additionally, we are able to amplify CWD agent from brain tissue and lymph nodes of CWD-positive white-tailed deer having Prnp alleles associated with reduced disease susceptibility.

  16. Lung Cancer Screening Update.

    Science.gov (United States)

    Ruchalski, Kathleen L; Brown, Kathleen

    2016-07-01

    Since the release of the US Preventive Services Task Force and Centers for Medicare and Medicaid Services recommendations for lung cancer screening, low-dose chest computed tomography screening has moved from the research arena to clinical practice. Lung cancer screening programs must reach beyond image acquisition and interpretation and engage in a multidisciplinary effort of clinical shared decision-making, standardization of imaging and nodule management, smoking cessation, and patient follow-up. Standardization of radiologic reports and nodule management will systematize patient care, provide quality assurance, further reduce harm, and contain health care costs. Although the National Lung Screening Trial results and eligibility criteria of a heavy smoking history are the foundation for the standard guidelines for low-dose chest computed tomography screening in the United States, currently only 27% of patients diagnosed with lung cancer would meet US lung cancer screening recommendations. Current and future efforts must be directed to better delineate those patients who would most benefit from screening and to ensure that the benefits of screening reach all socioeconomic strata and racial and ethnic minorities. Further optimization of lung cancer screening program design and patient eligibility will assure that lung cancer screening benefits will outweigh the potential risks to our patients. PMID:27306387

  17. Experimental observation of sub-terahertz backward-wave amplification in a multi-level microfabricated slow-wave circuit

    Energy Technology Data Exchange (ETDEWEB)

    Baik, Chan-Wook, E-mail: cw.baik@samsung.com; Ahn, Ho Young; Kim, Yongsung; Lee, Jooho; Hong, Seogwoo; Lee, Sang Hun; Choi, Jun Hee; Kim, Sunil; Kim, Jong Min; Hwang, Sungwoo [Samsung Advanced Institute of Technology, Suwon 443-803 (Korea, Republic of); Jeon, So-Yeon; Yu, SeGi [Department of Physics, Hankuk University of Foreign Studies, Yongin 449-791 (Korea, Republic of); Collins, George; Read, Michael E.; Lawrence Ives, R. [Calabazas Creek Research, Inc., San Mateo, California 94404-1010 (United States)

    2015-11-09

    In our earlier paper dealing with dispersion retrieval from ultra-deep, reactive-ion-etched, slow-wave circuits on silicon substrates, it was proposed that splitting high-aspect-ratio circuits into multilevels enabled precise characterization in sub-terahertz frequency regime. This achievement prompted us to investigate beam-wave interaction through a vacuum-sealed integration with a 15-kV, 85-mA, thermionic, electron gun. Our experimental study demonstrates sub-terahertz, backward-wave amplification driven by an external oscillator. The measured output shows a frequency downshift, as well as power amplification, from beam loading even with low beam perveance. This offers a promising opportunity for the development of terahertz radiation sources, based on silicon technologies.

  18. Screening in liver disease.

    Science.gov (United States)

    Del Poggio, Paolo; Mazzoleni, Marzio

    2006-09-01

    A disease is suitable for screening if it is common, if the target population can be identified and reached and if both a good screening test and an effective therapy are available. Of the most common liver diseases only viral hepatitis and genetic hemochromatosis partially satisfy these conditions. Hepatitis C is common, the screening test is good and the therapy eliminates the virus in half of the cases, but problems arise in the definition of the target population. In fact generalized population screening is not endorsed by international guidelines, although some recommend screening immigrants from high prevalence countries. Opportunistic screening (case finding) of individuals with classic risk factors, such as transfusion before 1992 and drug addiction, is the most frequently used strategy, but there is disagreement whether prison inmates, individuals with a history of promiscuous or traumatic sex and health care workers should be screened. In a real practice setting the performance of opportunistic screening by general practitioners is low but can be ameliorated by training programs. Screening targeted to segments of the population or mass campaigns are expensive and therefore interventions should be aimed to improve opportunistic screening and the detection skills of general practitioners. Regarding genetic hemochromatosis there is insufficient evidence for population screening, but individual physicians can decide to screen racial groups with a high prevalence of the disease, such as people in early middle age and of northern European origin. In the other cases opportunistic screening of high risk individuals should be performed, with a high level of suspicion in case of unexplained liver disease, diabetes, juvenile artropathy, sexual dysfunction and skin pigmentation. PMID:16981254

  19. Screening in liver disease

    Institute of Scientific and Technical Information of China (English)

    Paolo Del Poggio; Marzio Mazzoleni

    2006-01-01

    A disease is suitable for screening if it is common, if the target population can be identified and reached and if both a good screening test and an effective therapy are available. Of the most common liver diseases only viral hepatitis and genetic hemochromatosis partially satisfy these conditions. Hepatitis C is common, the screening test is good and the therapy eliminates the virus in half of the cases, but problems arise in the definition of the target population. In fact generalized population screening is not endorsed by international guidelines,although some recommend screening immigrants from high prevalence countries. Opportunistic screening (case finding) of individuals with classic risk factors,such as transfusion before 1992 and drug addiction,is the most frequently used strategy, but there is disagreement whether prison inmates, individuals with a history of promiscuous or traumatic sex and health care workers should be screened. In a real practice setting the performance of opportunistic screening by general practitioners is low but can be ameliorated by training programs. Screening targeted to segments of the population or mass campaigns are expensive and therefore interventions should be aimed to improve opportunistic screening and the detection skills of general practitioners. Regarding genetic hemochromatosis there is insufficient evidence for population screening, but individual physicians can decide to screen racial groups with a high prevalence of the disease, such as people in early middle age and of northern European origin. In the other cases opportunistic screening of high risk individuals should be performed, with a high level of suspicion in case of unexplained liver disease, diabetes, juvenile artropathy, sexual dysfunction and skin pigmentation.

  20. Subtyping of Streptococcus uberis by DNA amplification fingerprinting.

    OpenAIRE

    Jayarao, B. M.; Bassam, B J; Caetano-Anollés, G; Gresshoff, P M; Oliver, S P

    1992-01-01

    Total DNA of Streptococcus uberis from cows with mastitis was analyzed by DNA amplification fingerprinting (DAF) and compared with restriction endonuclease fingerprinting (REF). DAF grouped 22 strains into 15 distinct patterns, while REF grouped them into 12 patterns. These results suggest that DAF is a useful technique for subtyping strains of S. uberis.

  1. Soft x-ray amplification in an ablative capillary discharge

    International Nuclear Information System (INIS)

    Soft x-ray amplification in CVI 18.2 nm line is observed in an ablative UHMW-PE capillary discharge. The gain coefficient is measured to be 1.9 cm-1. The electron density is about 2 x 1019 cm-3. This indicates that capillary discharge pumping device can be a source for a compact soft x-ray laser. (author)

  2. Direct Extraction and Amplification of DNA from Soil.

    Science.gov (United States)

    Trevors, Jack T.; Leung, K.

    1998-01-01

    Presents an exercise that describes the direct extraction and purification of DNA from a small soil sample. Also discusses the subsequent amplification of a 343-bp Tn7 transposate A gene fragment (tnsA) from a strain of Pseudomonas aureofaciens 3732RNL11. Contains 21 references. (DDR)

  3. Resonant amplification of quantum fluctuations in a spinor gas

    DEFF Research Database (Denmark)

    Topic, O.; Scherer, M.; Gebreyesus, G.;

    2010-01-01

    Bose-Einstein condensates of atoms with non-zero spin are known to constitute an ideal system to investigate fundamental properties of magnetic superfluids. More recently it was realized that they also provide the fascinating opportunity to investigate the macroscopic amplification of quantum and...

  4. Reversible Gating of Plasmonic Coupling for Optical Signal Amplification.

    Science.gov (United States)

    Khoury, Christopher G; Fales, Andrew M; Vo-Dinh, Tuan

    2016-07-20

    Amplification of optical signals is useful for a wide variety of applications, ranging from data signal transmission to chemical sensing and biomedical diagnostics. One such application in chemical sensing is surface-enhanced Raman scattering (SERS), an important technique for increasing the Raman signal using the plasmonic effect of enhanced electromagnetic fields associated with metallic nanostructures. One of the most important limitations of SERS-based amplification is the difficulty to reproducibly control the SERS signal. Here, we describe the design and implementation of a unique hybrid system capable of producing reversible gating of plasmonic coupling for Raman signal amplification. The hybrid system is composed of two subsystems: (1) colloidal magneto-plasmonic nanoparticles for SERS enhancement and (2) a micromagnet substrate with an externally applied magnetic field to modulate the colloidal nanoparticles. For this proof of concept demonstration, the nanoparticles were labeled with a Raman-active dye, and it was shown that the detected SERS signal could be reproducibly modulated by controlling the externally applied magnetic field. The developed system provides a simple, robust, inexpensive, and reusable device for SERS signal modulation. These properties will open up new possibilities for optical signal amplification and gating as well for high-throughput, reproducible SERS detection. PMID:27347606

  5. Four-quadrant flyback converter for direct audio power amplification

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2005-01-01

    This paper presents a bidirectional, four-quadrant flyback converter for use in direct audio power amplification. When compared to the standard Class-D switching audio power amplifier with a separate power supply, the proposed four-quadrant flyback converter provides simple solution with better...

  6. Loss of KLF14 triggers centrosome amplification and tumorigenesis.

    Science.gov (United States)

    Fan, Guangjian; Sun, Lianhui; Shan, Peipei; Zhang, Xianying; Huan, Jinliang; Zhang, Xiaohong; Li, Dali; Wang, Tingting; Wei, Tingting; Zhang, Xiaohong; Gu, Xiaoyang; Yao, Liangfang; Xuan, Yang; Hou, Zhaoyuan; Cui, Yongping; Cao, Liu; Li, Xiaotao; Zhang, Shengping; Wang, Chuangui

    2015-01-01

    Centrosome amplification is frequent in cancer, but the underlying mechanisms remain unclear. Here we report that disruption of the Kruppel-like factor 14 (KLF14) gene in mice causes centrosome amplification, aneuploidy and spontaneous tumorigenesis. Molecularly, KLF14 functions as a transcriptional repressor of Plk4, a polo-like kinase whose overexpression induces centrosome overduplication. Transient knockdown of KLF14 is sufficient to induce Plk4-directed centrosome amplification. Clinically, KLF14 transcription is significantly downregulated, whereas Plk4 transcription is upregulated in multiple types of cancers, and there exists an inverse correlation between KLF14 and Plk4 protein expression in human breast and colon cancers. Moreover, KLF14 depletion promotes AOM/DSS-induced colon tumorigenesis. Our findings reveal that KLF14 reduction serves as a mechanism leading to centrosome amplification and tumorigenesis. On the other hand, forced expression of KLF14 leads to mitotic catastrophe. Collectively, our findings identify KLF14 as a tumour suppressor and highlight its potential as biomarker and therapeutic target for cancer. PMID:26439168

  7. Transient amplification limits noise suppression in biochemical networks

    Science.gov (United States)

    Dixon, John; Lindemann, Anika; McCoy, Jonathan H.

    2016-01-01

    Cell physiology is orchestrated, on a molecular level, through complex networks of biochemical reactions. The propagation of random fluctuations through these networks can significantly impact cell behavior, raising challenging questions about how network design shapes the cell's ability to suppress or exploit these fluctuations. Here, drawing on insights from statistical physics, fluid dynamics, and systems biology, we explore how transient amplification phenomena arising from network connectivity naturally limit a biochemical system's ability to suppress small fluctuations around steady-state behaviors. We find that even a simple system consisting of two variables linked by a single interaction is capable of amplifying small fluctuations orders of magnitude beyond the levels predicted by linear stability theory. We also find that adding additional interactions can promote further amplification, even when these interactions implement classic design strategies known to suppress fluctuations. These results establish that transient amplification is an essential factor determining baseline noise levels in stable intracellular networks. Significantly, our analysis is not bound to specific systems or interaction mechanisms: we find that noise amplification is an emergent phenomenon found near steady states in any network containing sufficiently strong interactions, regardless of its form or function.

  8. Development of an electronic system for signals amplification

    International Nuclear Information System (INIS)

    This paper presents the obtained results with a spectrometer for electromagnetic radiation whose detector, a Si PIN type diode, was directly coupled to a signal amplification system developed in this project for scientific initiation. The linearity conditions and the gain operational limits, constituted of two stages of amplification based on the employment of devices from AMTEK A225 and A206, were determined using a precision pulse generator. The obtained results shown that the developed system is stable and linear in the gain range of 50-150. The spectrometric response of the electronic system coupled to the Siemens SFH-00206 type diode, were studied in view of the register of the 59.5 keV gamma ray spectra proceeding from 241Am as function of the reversal polarization voltage. The influence pf the voltage and the electronic contribution in the energy resolution of the registered spectra under room temperature (22 degree Celsius) had also investigated considering the more adequate value of the coupling capacitance of the amplification system diode. Up to the present. the best energy resolution (FWHM = 4.85 keV) of the 59.5 keV line was obtained for the condition of the detector polarization at 16 V. This result proves that the signal amplification system developed coupled to the SFH00206 diode, besides the low cost, excellent operational condition for the detection and spectrometry or low energy electromagnetic radiation

  9. Utilization of non-linear converters for audio amplification

    DEFF Research Database (Denmark)

    Iversen, Niels Elkjær; Birch, Thomas; Knott, Arnold

    2012-01-01

    . The introduction of non-linear converters for audio amplification defeats this limitation. A Cuk converter, designed to deliver an AC peak output voltage twice the supply voltage, is presented in this paper. A 3V prototype has been developed to prove the concept. The prototype shows that it is...

  10. Touch/Screen

    Directory of Open Access Journals (Sweden)

    Daniel Ross

    2015-12-01

    Full Text Available In 2004 Bernard Stiegler posed “the tragic question of cinema” as that of the germ of regres-­‐‑ sion to television and pornography it has always contained, just as in 1944 Adorno and Hork-­‐‑ heimer argued that Enlightenment reason has always contained a germ of regression making possible a prostitution of theory leading only to the threat of fascism. If comparable threats attend Stiegler’s cinematic question, then this implies the need for an account of this potential for regression, that is, an account of the relationship between desire, technology and knowledge. Tracing the aporias of the origin of desire and trauma in psychoanalysis is one crucial way to pursue this account. Exiting these aporias depends on recognizing that the origin of desire has for human beings always been technical, and hence that the instruments of desire form its conditions and condition its forms. By thus analysing the staging of desire and the setting of fantasy it becomes possible to reflect, for example, on what it means that for Genet fascism was theatre, that for Syberberg Hitler was cinema, and that for Stiegler the new prostitution of the tele-­‐‑visual graphic is digital and algorithmic. Hence arises the potentially tragic question of the possibility or otherwise, in the age of the ubiquitous screen, of a new cinematic invention and a new cinematic practice.

  11. TPR-MET oncogenic rearrangement: Detection by polymerase chain reaction amplification of the transcript and expression in human tumor cells lines

    International Nuclear Information System (INIS)

    Activation of the MET protooncogene by a rearrangement involving the fusion of TPR and MET specific gene sequences has been observed in a human osteosarcoma cell line (HOS) treated in vitro with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). No information has been available about the possible occurrence of this rearrangement in human tumors. To facilitate rapid screening of human cell lines and tumor samples for this specific gene rearrangement; the authors developed a sensitive detection method based on polymerase chain reaction (PCR) amplification of TPR-MET mRNA. cDNA was generated from cellular transcripts by using one of the PCR primers, which was then used as a template for PCR amplification of a 205-base-pair region carrying the breakpoint. An end-labeled internal probe was hybridized in solution to an aliquot of the PCR product for detecting amplification. Cells could be directly screened by the assay without prior isolation of RNA. A 205-base-pair DNA fragment characteristic of the TRP-MET rearrangement was detected in cell lines previously known to contain this altered sequence. The rearrangement was also detected at very low levels in the parental (nontransformed) cell line, HOS TE-85. A preliminary survey of cell lines derived from a variety of human tumors indicates that TPR-MET rearrangement occurred and was expressed at very low frequencies by cells from 7 of 14 tumors of nonhematopoietic origin

  12. A novel method, digital genome scanning detects KRAS gene amplification in gastric cancers: involvement of overexpressed wild-type KRAS in downstream signaling and cancer cell growth

    Directory of Open Access Journals (Sweden)

    Yanagihara Kazuyoshi

    2009-06-01

    Full Text Available Abstract Background Gastric cancer is the third most common malignancy affecting the general population worldwide. Aberrant activation of KRAS is a key factor in the development of many types of tumor, however, oncogenic mutations of KRAS are infrequent in gastric cancer. We have developed a novel quantitative method of analysis of DNA copy number, termed digital genome scanning (DGS, which is based on the enumeration of short restriction fragments, and does not involve PCR or hybridization. In the current study, we used DGS to survey copy-number alterations in gastric cancer cells. Methods DGS of gastric cancer cell lines was performed using the sequences of 5000 to 15000 restriction fragments. We screened 20 gastric cancer cell lines and 86 primary gastric tumors for KRAS amplification by quantitative PCR, and investigated KRAS amplification at the DNA, mRNA and protein levels by mutational analysis, real-time PCR, immunoblot analysis, GTP-RAS pull-down assay and immunohistochemical analysis. The effect of KRAS knock-down on the activation of p44/42 MAP kinase and AKT and on cell growth were examined by immunoblot and colorimetric assay, respectively. Results DGS analysis of the HSC45 gastric cancer cell line revealed the amplification of a 500-kb region on chromosome 12p12.1, which contains the KRAS gene locus. Amplification of the KRAS locus was detected in 15% (3/20 of gastric cancer cell lines (8–18-fold amplification and 4.7% (4/86 of primary gastric tumors (8–50-fold amplification. KRAS mutations were identified in two of the three cell lines in which KRAS was amplified, but were not detected in any of the primary tumors. Overexpression of KRAS protein correlated directly with increased KRAS copy number. The level of GTP-bound KRAS was elevated following serum stimulation in cells with amplified wild-type KRAS, but not in cells with amplified mutant KRAS. Knock-down of KRAS in gastric cancer cells that carried amplified wild

  13. A novel method, digital genome scanning detects KRAS gene amplification in gastric cancers: involvement of overexpressed wild-type KRAS in downstream signaling and cancer cell growth

    International Nuclear Information System (INIS)

    Gastric cancer is the third most common malignancy affecting the general population worldwide. Aberrant activation of KRAS is a key factor in the development of many types of tumor, however, oncogenic mutations of KRAS are infrequent in gastric cancer. We have developed a novel quantitative method of analysis of DNA copy number, termed digital genome scanning (DGS), which is based on the enumeration of short restriction fragments, and does not involve PCR or hybridization. In the current study, we used DGS to survey copy-number alterations in gastric cancer cells. DGS of gastric cancer cell lines was performed using the sequences of 5000 to 15000 restriction fragments. We screened 20 gastric cancer cell lines and 86 primary gastric tumors for KRAS amplification by quantitative PCR, and investigated KRAS amplification at the DNA, mRNA and protein levels by mutational analysis, real-time PCR, immunoblot analysis, GTP-RAS pull-down assay and immunohistochemical analysis. The effect of KRAS knock-down on the activation of p44/42 MAP kinase and AKT and on cell growth were examined by immunoblot and colorimetric assay, respectively. DGS analysis of the HSC45 gastric cancer cell line revealed the amplification of a 500-kb region on chromosome 12p12.1, which contains the KRAS gene locus. Amplification of the KRAS locus was detected in 15% (3/20) of gastric cancer cell lines (8–18-fold amplification) and 4.7% (4/86) of primary gastric tumors (8–50-fold amplification). KRAS mutations were identified in two of the three cell lines in which KRAS was amplified, but were not detected in any of the primary tumors. Overexpression of KRAS protein correlated directly with increased KRAS copy number. The level of GTP-bound KRAS was elevated following serum stimulation in cells with amplified wild-type KRAS, but not in cells with amplified mutant KRAS. Knock-down of KRAS in gastric cancer cells that carried amplified wild-type KRAS resulted in the inhibition of cell growth and

  14. Bacteriophage Amplification-Coupled Detection and Identification of Bacterial Pathogens

    Science.gov (United States)

    Cox, Christopher R.; Voorhees, Kent J.

    Current methods of species-specific bacterial detection and identification are complex, time-consuming, and often require expensive specialized equipment and highly trained personnel. Numerous biochemical and genotypic identification methods have been applied to bacterial characterization, but all rely on tedious microbiological culturing practices and/or costly sequencing protocols which render them impractical for deployment as rapid, cost-effective point-of-care or field detection and identification methods. With a view towards addressing these shortcomings, we have exploited the evolutionarily conserved interactions between a bacteriophage (phage) and its bacterial host to develop species-specific detection methods. Phage amplification-coupled matrix assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF-MS) was utilized to rapidly detect phage propagation resulting from species-specific in vitro bacterial infection. This novel signal amplification method allowed for bacterial detection and identification in as little as 2 h, and when combined with disulfide bond reduction methods developed in our laboratory to enhance MALDI-TOF-MS resolution, was observed to lower the limit of detection by several orders of magnitude over conventional spectroscopy and phage typing methods. Phage amplification has been combined with lateral flow immunochromatography (LFI) to develop rapid, easy-to-operate, portable, species-specific point-of-care (POC) detection devices. Prototype LFI detectors have been developed and characterized for Yersinia pestis and Bacillus anthracis, the etiologic agents of plague and anthrax, respectively. Comparable sensitivity and rapidity was observed when phage amplification was adapted to a species-specific handheld LFI detector, thus allowing for rapid, simple, POC bacterial detection and identification while eliminating the need for bacterial culturing or DNA isolation and amplification techniques.

  15. New perspectives on microbial community distortion after whole-genome amplification

    Science.gov (United States)

    Whole-genome amplification (WGA) has become an important tool to explore the genomic information of microorganisms in an environmental sample with limited biomass, however potential selective biases during the amplification processes are poorly understood. Here, we describe the e...

  16. Tissue donation and virus safety: more nucleic acid amplification testing is needed.

    Science.gov (United States)

    Pruss, A; Caspari, G; Krüger, D H; Blümel, J; Nübling, C M; Gürtler, L; Gerlich, W H

    2010-10-01

    In tissue and organ transplantation, it is of great importance to avoid the transmission of blood-borne viruses to the recipient. While serologic testing for anti-human immunodeficiency virus (HIV)-1 and -2, anti-hepatitis C virus (HCV), hepatitis B surface antigen (HBsAg), anti-hepatitis B core antigen (HBc), and Treponema pallidum infection is mandatory, there is until now in most countries no explicit demand for nucleic acid amplification testing (NAT) to detect HIV, hepatitis B virus (HBV), and HCV infection. After a review of reports in the literature on viral transmission events, tissue-specific issues, and manufacturing and inactivation procedures, we evaluated the significance of HIV, HCV, and HBV detection using NAT  in  donors of various types of tissues and compared our results with the experiences of blood banking organizations. There is a significant risk of HIV, HCV, and HBV transmission by musculoskeletal tissues because of their high blood content and the high donor-recipient ratio. If no effective virus inactivation procedure for musculoskeletal tissue is applied, donors should be screened using NAT  for  HIV, HCV, and HBV. Serologically screened cardiovascular tissue carries a very low risk of HIV, HCV, or HBV transmission. Nevertheless, because effective virus inactivation is impossible (retention of tissue morphology) and the donor-recipient ratio may be as high as 1:10, we concluded that NAT  should be performed for HIV, HCV, and HBV as an additional safety measure. Although cornea allografts carry the lowest risk of transmitting HIV, HCV, and HBV  owing to corneal physiology, morphology, and the epidemiology of corneal diseases, NAT  for  HCV should still be performed. If the NAT  screening of a donor for HIV, HCV, and HBV is negative, quarantine storage of the donor tissue seems dispensable. In view of numerous synergistic effects with transfusion medicine, it would be advantageous for tissue banks to cooperate with blood

  17. Diabetes Screening Among Immigrants

    OpenAIRE

    Creatore, Maria I.; Gillian L Booth; Manuel, Douglas G.; Moineddin, Rahim; Glazier, Richard H.

    2012-01-01

    OBJECTIVE To examine diabetes screening, predictors of screening, and the burden of undiagnosed diabetes in the immigrant population and whether these estimates differ by ethnicity. RESEARCH DESIGN AND METHODS A population-based retrospective cohort linking administrative health data to immigration files was used to follow the entire diabetes-free population aged 40 years and up in Ontario, Canada (N = 3,484,222) for 3 years (2004–2007) to determine whether individuals were screened for diabe...

  18. In-bead screening

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to screening of one-bead-one-compound (OBOC) combinatorial libraries which is useful for the discovery of compounds displaying molecular interactions with a biological or a physicochemical system, such as substrates and inhibitors of enzymes and the like. The invention...... provides a method for screening a library of compounds for their interaction with a physico- chemical or biological system and a corresponding kit for performing the method of screening a one-bead-one-compound library of compounds....

  19. The Kondo Screening Cloud

    OpenAIRE

    Affleck, Ian

    2001-01-01

    Renormalization group theory of the Kondo effect predicts that an impurity spin is screened by a conduction electron spread over a large distance of order >.1 to 1 micron. This review has the following sections: 1. The Kondo effect and the screening cloud, 2. Non-observation of the Kondo cloud in conventional experiments, 3. Kondo effect in transmission through a quantum dot, 4. Observing the screening cloud in persistent current experiments, 5. Side-coupled quantum dot, 6. Conclusions

  20. Nuclemeter: A Reaction-Diffusion Column for Quantifying Nucleic Acids Undergoing Enzymatic Amplification

    Science.gov (United States)

    Bau, Haim; Liu, Changchun; Killawala, Chitvan; Sadik, Mohamed; Mauk, Michael

    2014-11-01

    Real-time amplification and quantification of specific nucleic acid sequences plays a major role in many medical and biotechnological applications. In the case of infectious diseases, quantification of the pathogen-load in patient specimens is critical to assessing disease progression, effectiveness of drug therapy, and emergence of drug-resistance. Typically, nucleic acid quantification requires sophisticated and expensive instruments, such as real-time PCR machines, which are not appropriate for on-site use and for low resource settings. We describe a simple, low-cost, reactiondiffusion based method for end-point quantification of target nucleic acids undergoing enzymatic amplification. The number of target molecules is inferred from the position of the reaction-diffusion front, analogous to reading temperature in a mercury thermometer. We model the process with the Fisher Kolmogoroff Petrovskii Piscounoff (FKPP) Equation and compare theoretical predictions with experimental observations. The proposed method is suitable for nucleic acid quantification at the point of care, compatible with multiplexing and high-throughput processing, and can function instrument-free. C.L. was supported by NIH/NIAID K25AI099160; M.S. was supported by the Pennsylvania Ben Franklin Technology Development Authority; C.K. and H.B. were funded, in part, by NIH/NIAID 1R41AI104418-01A1.

  1. Cross-subtype detection of HIV-1 using reverse transcription and recombinase polymerase amplification.

    Science.gov (United States)

    Lillis, Lorraine; Lehman, Dara A; Siverson, Joshua B; Weis, Julie; Cantera, Jason; Parker, Mathew; Piepenburg, Olaf; Overbaugh, Julie; Boyle, David S

    2016-04-01

    A low complexity diagnostic test that rapidly and reliably detects HIV infection in infants at the point of care could facilitate early treatment, improving outcomes. However, many infant HIV diagnostics can only be performed in laboratory settings. Recombinase polymerase amplification (RPA) is an isothermal amplification technology that can rapidly amplify proviral DNA from multiple subtypes of HIV-1 in under twenty minutes without complex equipment. In this study we added reverse transcription (RT) to RPA to allow detection of both HIV-1 RNA and DNA. We show that this RT-RPA HIV-1 assay has a limit of detection of 10-30 copies of an exact sequence matched DNA or RNA, respectively. In addition, at 100 copies of RNA or DNA, the assay detected 171 of 175 (97.7%) sequence variants that represent all the major subtypes and recombinant forms of HIV-1 Groups M and O. This data suggests that the application of RT-RPA for the combined detection of HIV-1 viral RNA and proviral DNA may prove a highly sensitive tool for rapid and accurate diagnosis of infant HIV. PMID:26821087

  2. GENOMIC PROFILING BY MULTIPLEX LIGATION - DEPENDENT PROBE AMPLIFICATION IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS

    Directory of Open Access Journals (Sweden)

    Georgiana-Emilia Grigore

    2013-11-01

    Full Text Available The clinical management of severe pathological conditions, such as B-cell chronic lymphocytic leukemia (B-CLL, is subject to continuous optimization and re-evaluation. Patients may fully benefit from rapid, standardized laboratory tools designed to facilitate their early stratification according to disease risk, stage and prognosis. Such technologies may also aid the clinician in selecting the therapeutic option with the greatest chances of success. The presence of specific genetic abnormalities are frequently associated with the clinical outcome of oncologic patients in general, and B-CLL patients in particular. In the current study, a group of 58 B-CLL patients were evaluated for the detection of gene copy number alterations (deletions or duplication/ amplifications within 45 distinct genetic targets, by means of a novel molecular methodology, Multiplex Ligation - Dependent Probe Amplification (MLPA. Simple or complex genetic defects were identified in 67% of cases, and the most common aberrations observed were: deletion of the short arm of chromosome 13 in 33% of cases, deletion of the long arm of chromosome 11 in 16% of cases, trisomy 12 in 16% of cases, and deletion of the short arm of chromosome 17 in 7% of cases. The main conclusion of the study presented here points towards MLPA as a potential key step of clinical management protocols in B-CLL, providing that it will be fully standardised for routine diagnosis.

  3. Non-local effect in Brillouin optical time-domain analyzer based on Raman amplification

    International Nuclear Information System (INIS)

    Compared with conventional Brillouin optical time-domain analyzer (BOTDA), the BOTDA based on Raman amplification allows longer sensing range, higher signal-to-noise ratio and higher measurement accuracy. However, the non-local effect induced by pump depletion significantly restricts the probe optical power injected to sensing fiber, thereby limiting the further extension for sensing distance. In this paper, the coupled equations including the interaction of probe light, Brillouin and Raman pumps are applied to the study on the non-local characteristics of BOTDA based on Raman amplification. The results show that, the system error induced by non-local effect worsens with increased powers of probe wave and Raman pump. The frequency-division-multiplexing (cascading the fibers with various Brillouin frequency shifts) and time-division-multiplexing (modulating both of the Brillouin pump and probe lights) technologies are efficient approaches to suppress the non-local effect, through shortening the effective interaction range between Brillouin pump and probe lights. (authors)

  4. Digital Droplet Multiple Displacement Amplification (ddMDA) for Whole Genome Sequencing of Limited DNA Samples

    OpenAIRE

    Minsoung Rhee; Yooli K Light; Meagher, Robert J.; Anup K. Singh

    2016-01-01

    Multiple displacement amplification (MDA) is a widely used technique for amplification of DNA from samples containing limited amounts of DNA (e.g., uncultivable microbes or clinical samples) before whole genome sequencing. Despite its advantages of high yield and fidelity, it suffers from high amplification bias and non-specific amplification when amplifying sub-nanogram of template DNA. Here, we present a microfluidic digital droplet MDA (ddMDA) technique where partitioning of the template D...

  5. Amplification of cylindrically polarized laser beams in single crystal fiber amplifiers

    OpenAIRE

    Piehler, Stefan; Délen, Xavier; Rumpel, Martin; Didierjean, Julien; Aubry, Nicolas; Graf, Thomas; Balembois, François; Georges, Patrick; Abdou Ahmed, Marwan

    2013-01-01

    Yb:YAG single crystal fiber (SCF) amplifiers have recently drawn much attention in the field of amplification of ultra-short pulses. In this paper, we report on the use of SCF amplifiers for the amplification of cylindrically polarized laser beams, as such beams offer promising properties for numerous applications. While the amplification of cylindrically polarized beams is challenging with other amplifier designs due to thermally induced depolarization, we demonstrate the amplification of 32...

  6. New perspectives on assessing amplification effects.

    Science.gov (United States)

    Souza, Pamela E; Tremblay, Kelly L

    2006-09-01

    Clinicians have long been aware of the range of performance variability with hearing aids. Despite improvements in technology, there remain many instances of well-selected and appropriately fitted hearing aids whereby the user reports minimal improvement in speech understanding. This review presents a multistage framework for understanding how a hearing aid affects performance. Six stages are considered: (1) acoustic content of the signal, (2) modification of the signal by the hearing aid, (3) interaction between sound at the output of the hearing aid and the listener's ear, (4) integrity of the auditory system, (5) coding of available acoustic cues by the listener's auditory system, and (6) correct identification of the speech sound. Within this framework, this review describes methodology and research on 2 new assessment techniques: acoustic analysis of speech measured at the output of the hearing aid and auditory evoked potentials recorded while the listener wears hearing aids. Acoustic analysis topics include the relationship between conventional probe microphone tests and probe microphone measurements using speech, appropriate procedures for such tests, and assessment of signal-processing effects on speech acoustics and recognition. Auditory evoked potential topics include an overview of physiologic measures of speech processing and the effect of hearing loss and hearing aids on cortical auditory evoked potential measurements in response to speech. Finally, the clinical utility of these procedures is discussed. PMID:16959734

  7. Breast cancer screening

    OpenAIRE

    Skrabanek, P

    1988-01-01

    Consensus is still lacking on guidelines for breast-cancer screening with mammography: who should be screened, how frequently at what age, to what benefits and at what risks. American, Dutch, Swedish and Italian studies spanning the 1960s to the 1980s reveal a benefit from screening (reduced mortality from breast cancer) that occurs unambiguously only in women 50 years of age and over. Physicians who choose to screen mammographically their over-49-year-old female patients must do so with the ...

  8. Colorectal cancer screening

    Directory of Open Access Journals (Sweden)

    Almeida Frederico Ferreira Novaes de

    2000-01-01

    Full Text Available Colorectal cancer (CRC is the third most common cancer in the world, and mortality has remained the same for the past 50 years, despite advances in diagnosis and treatment. Because significant numbers of patients present with advanced or incurable stages, patients with pre-malignant lesions (adenomatous polyps that occur as result of genetic inheritance or age should be screened, and patients with long-standing inflammatory bowel disease should undergo surveillance. There are different risk groups for CRC, as well as different screening strategies. It remains to be determined which screening protocol is the most cost-effective for each risk catagory. The objective of screening is to reduce morbidity and mortality in a target population. The purpose of this review is to analyze the results of the published CRC screening studies, with regard to the measured reduction of morbidity and mortality, due to CRC in the studied populations, following various screening procedures. The main screening techniques, used in combination or alone, include fecal occult blood tests, flexible sigmoidoscopy, and colonoscopy. Evidence from the published literature on screening methods for specific risk groups is scanty and frequently does not arise from controlled studies. Nevertheless, data from these studies, combined with recent advances in molecular genetics, certainly lead the way to greater efficacy and lower cost of CRC screening.

  9. ScreenOS Cookbook

    CERN Document Server

    Brunner, Stefan; Delcourt, David

    2008-01-01

    In the only book that completely covers ScreenOS, six key members of Juniper Network's ScreenOS development team help you troubleshoot secure networks using ScreenOS firewall appliances. Over 200 recipes address a wide range of security issues, provide step-by-step solutions, and include discussions of why the recipes work, so you can easily set up and keep ScreenOS systems on track. The easy-to-follow format enables you to find the topic and specific recipe you need right away.

  10. Mammography screening in Denmark

    DEFF Research Database (Denmark)

    Vejborg, Ilse; Mikkelsen, Ellen Margrethe; Garne, Jens Peter;

    2011-01-01

    Mammography screening is offered healthy women, and a high standard on professional and organizational level is mandatory not only in the screening programme but even in the diagnostic work-up and treatment. The main goal is to achieve a substantial reduction in disease specific mortality, but it...... is not possible to evaluate the effect on mortality until several years later, and continuously monitoring of the quality of all aspects of a screening programme is necessary. Based on other European guidelines, 11 quality indicators have been defined, and guidelines concerning organizational...... requirements for a Danish screening programme as well as recommendations for the radiographic and radiological work have been drawn up....

  11. Screening for colorectal cancer

    DEFF Research Database (Denmark)

    Nielsen, Hans J; Jakobsen, Karen V; Christensen, Ib J;

    2011-01-01

    Emerging results indicate that screening improves survival of patients with colorectal cancer. Therefore, screening programs are already implemented or are being considered for implementation in Asia, Europe and North America. At present, a great variety of screening methods are available including...... into improvements of screening for colorectal cancer includes blood-based biological markers, such as proteins, DNA and RNA in combination with various demographically and clinically parameters into a "risk assessment evaluation" (RAE) test. It is assumed that such a test may lead to higher acceptance among...... procedures for colorectal cancer. Therefore, results of present research, validating RAE tests, are awaited with interest....

  12. The influence of off-screen landmarks on user orientation

    OpenAIRE

    Korda, Amichai

    2014-01-01

    Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies. Maps displayed on hand held devices, such as smartphones; provide limited visibility due to their small screen display. In order to overcome display limitations, researchers have developed new techniques that point users to objects and landmarks located off-screen, which is known as an “off-screen interface”. Since this is a new type of map interface, there is l...

  13. Information management for entomology screening.

    Science.gov (United States)

    Curtis, Jane; Huesing, Joseph; Simpson, Robert; Elands, Jack

    2004-02-01

    The successful introduction of genetically modified (GM) crops has created a revolutionary transformation of the agricultural industry with GM crops currently planted on some 130 million acres. Historically, agricultural companies were involved in the discovery of conventional insecticide chemistries in processes that were very similar to those in the pharmaceutical industry. With the introduction of GM technologies, the process has radically changed. The new process is best described as the pharmaceutical equivalent of a very large-scale limited clinical trial conducted at the discovery stage. For example, unlike pharmaceutical screens, GM crop discovery screens frequently involve live insects challenged with complex protein containing soups. Furthermore, the nature of the potential avenues for discovery mandates that assay models also support protein engineering, proteomics, and genomics efforts. The range in sample demand ranges from ultra-low to high throughput. Finally, regulatory and good business stewardship demands that data integrity and tractability is in place, from discovery through varietal introduction, to manage the information generated in support of a commercialized GM plant variety. The authors describe their discovery workflow and detail how they have customized a commercially available database software package to achieve an optimum configuration for entomology screening. PMID:15006147

  14. 中美青少年科技竞赛筛选机制的比较研究%A Comparative Study on Screening Mechanism of the Youth Science and Technology Competitions in China and America

    Institute of Scientific and Technical Information of China (English)

    李冬晖; 胡咏梅

    2012-01-01

    CASTIC and APFS are two youth science and technology competitions of great importance in China. ISEF and STS ale. two important competitions in America. This paper makes a Sino-US comparative study of the screening mechanism. On the basis of the study, some suggestions have been put forward. (1) To simplify the assessment part of our competitions and improve the effectiveness of the overall quality assessment. (2) To refine evaluation criteria, extend assessment dimensions and set the dimensions' weights with the scientific method. (3) To expand the provincial assessor scope of CASTIC and share provincial assessors as soon as possible. (4) To strengthen the provincial assessor training to ensure the orderly and efficient conducting of assessment.%青少年科技创新大赛、"明天小小科学家"奖励活动是中国最具影响力的两个青少年科技赛事,英特尔国际科学与工程学大赛、美国科学人才选拔赛是美国的两大知名赛事。本研究从竞赛阶段类型、筛选形式、评审环节和评审标准4个角度,对以上竞赛的筛选机制进行了深入比较,并在此基础上提出如下建议:(1)简化竞赛的评审环节,提高综合素质考察环节的有效性;(2)细化评审标准,扩展评审维度,科学设定各维度权重;(3)扩大省赛评委的选择范围,实现各省评委的共享;(4)加强省赛评委的培训。

  15. Amplification of target-specific, ligation-dependent circular probe.

    Science.gov (United States)

    Zhang, D Y; Brandwein, M; Hsuih, T C; Li, H

    1998-05-12

    We describe a novel polymerase chain reaction (PCR)-based gene amplification method utilizing a circularizable oligodeoxyribonucleotide probe (C-probe). The C-probe contains two target complementary regions located at each terminus and an interposed generic PCR primer binding region. The hybridization of C-probe to a target brings two termini in direct apposition as the complementary regions of C-probe wind around the target to form a double helix. Subsequent ligation of the two termini results in a covalently linked C-probe that becomes 'locked on to' the target. The circular nature of the C-probe allows for the generation of a multimeric single-stranded DNA (ssDNA) via extension of the antisense primer by Taq DNA polymerase along the C-probe and displacement of downstream strand, analogous to 'rolling circle' replication of bacteriophage in vivo. This multimeric ssDNA then serves as a template for multiple sense primers to hybridize, extend, and displace downstream DNA, generating a large ramified (branching) DNA complex. Subsequent thermocycling denatures the dsDNA and initiates the next round of primer extension and ramification. This model results in significantly improved amplification kinetics (super-exponential) as compared to conventional PCR. Our results show that the C-probe was 1000 times more sensitive than the corresponding linear hemiprobes for detecting Epstein-Barr virus early RNA. The C-probe not only increases the power of amplification but also offers a means for decontaminating carryover amplicons. As the ligated C-probes possess no free termini, they are resistant to exonuclease digestion, whereas contaminated linear amplicons are susceptible to digestion. Treatment of the ligation reaction mixture with exonuclease prior to amplification eliminated the amplicon contaminant, which could also have been co-amplified with the same PCR primers; only the ligated C-probes were amplified. The combined advantages of the C-probe and thermocycling have a

  16. Construction Strategy for an Internal Amplification Control for Real-Time Diagnostic Assays Using Nucleic Acid Sequence-Based Amplification: Development and Clinical Application

    OpenAIRE

    Rodríguez-Lázaro, David; D'Agostino, Martin; Pla, Maria; Cook, Nigel

    2005-01-01

    An important analytical control in molecular amplification-based methods is an internal amplification control (IAC), which should be included in each reaction mixture. An IAC is a nontarget nucleic acid sequence which is coamplified simultaneously with the target sequence. With negative results for the target nucleic acid, the absence of an IAC signal indicates that amplification has failed. A general strategy for the construction of an IAC for inclusion in molecular beacon-based real-time nu...

  17. Risk of cancer radioinduced by mammographic screening

    International Nuclear Information System (INIS)

    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

  18. Optical touch screen based on waveguide sensing

    DEFF Research Database (Denmark)

    Pedersen, Henrik Chresten; Jakobsen, Michael Linde; Hanson, Steen Grüner;

    2011-01-01

    We disclose a simple, optical touch screen technique based on a planar injection molded polymer waveguide, a single laser, and a small linear detector array. The solution significantly reduces the complexity and cost as compared to existing optical touch technologies. Force detection of a touching...

  19. Quenching of Unincorporated Amplification Signal Reporters in Reverse-Transcription Loop-Mediated Isothermal Amplification Enabling Bright, Single-Step, Closed-Tube, and Multiplexed Detection of RNA Viruses.

    Science.gov (United States)

    Ball, Cameron S; Light, Yooli K; Koh, Chung-Yan; Wheeler, Sarah S; Coffey, Lark L; Meagher, Robert J

    2016-04-01

    Reverse-transcription-loop-mediated isothermal amplification (RT-LAMP) has frequently been proposed as an enabling technology for simplified diagnostic tests for RNA viruses. However, common detection techniques used for LAMP and RT-LAMP have drawbacks, including poor discrimination capability, inability to multiplex targets, high rates of false positives, and (in some cases) the requirement of opening reaction tubes postamplification. Here, we present a simple technique that allows closed-tube, target-specific detection, based on inclusion of a dye-labeled primer that is incorporated into a target-specific amplicon if the target is present. A short, complementary quencher hybridizes to unincorporated primer upon cooling down at the end of the reaction, thereby quenching fluorescence of any unincorporated primer. Our technique, which we term QUASR (for quenching of unincorporated amplification signal reporters, read "quasar"), does not significantly reduce the amplification efficiency or sensitivity of RT-LAMP. Equipped with a simple LED excitation source and a colored plastic gel filter, the naked eye or a camera can easily discriminate between positive and negative QUASR reactions, which produce a difference in signal of approximately 10:1 without background subtraction. We demonstrate that QUASR detection is compatible with complex sample matrices such as human blood, using a novel LAMP primer set for bacteriophage MS2 (a model RNA virus particle). Furthermore, we demonstrate single-tube duplex detection of West Nile virus (WNV) and chikungunya virus (CHIKV) RNA. PMID:26980448

  20. Influence of preparation technology for soil and harvest the size of the damage of potato tubers.

    OpenAIRE

    BÁRTA, Petr

    2014-01-01

    Comparison of technology without the use of soil preparation and screening technologies using the screening. In this work I examine the damage of potato tubers in the collection, the technologies used and the yield.