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Sample records for techniques molecular beacon

  1. Quantum Dot Molecular Beacons for DNA Detection

    Science.gov (United States)

    Cady, Nathaniel C.

    Molecular beacons have become an important fluorescent probe for sequence-specific DNA detection. To improve the sensitivity and robustness of molecular beacon assays, fluorescent semiconductor quantum dots (QDs) are now being used as the fluorescent moiety for molecular beacon synthesis. Multiple linkage strategies can be used for attaching molecular beacon DNA to QDs, and multiple quenchers, including gold particles, can be used for fluorescence quenching. Covalent attachment of QDs to DNA can be achieved through amide linkage, and affinity-based attachment can be achieved with streptavidin-biotin linkage. We have shown that these linkage strategies can be used to successfully create quantum dot molecular beacons that can be used in DNA detection assays with high specificity.

  2. New frontiers of molecular beacons: signal amplification and nanomachines

    DEFF Research Database (Denmark)

    Della Vedova, Paolo

    2013-01-01

    by two complementary strands (stem), conjugated respectively with a fluorophore and a quencher. Upon hybridization with complementary target, the stem bonds break, parting the fluorophore from the quencher and resulting in a detectable signal. This thesis is divided in two major sections. The first...... section gives initially an overview of the molecular beacon technology usability and working principle. Later on the mechanism of molecular beacon’s internalization by SLO treatment was theoretically and experimentally investigated to determine optimal transfection condition and actual cell loading....... Finally the problem of signal generation by molecular beacons was tackled by developing two new methods. It was demonstrated that by carefully design of interacting beacons with a new geometrical configuration, it is possible to induce among them both a linear and an avalanche reaction which improve...

  3. Caged molecular beacons: controlling nucleic acid hybridization with light.

    Science.gov (United States)

    Wang, Chunming; Zhu, Zhi; Song, Yanling; Lin, Hui; Yang, Chaoyong James; Tan, Weihong

    2011-05-28

    We have constructed a novel class of light-activatable caged molecular beacons (cMBs) that are caged by locking two stems with a photo-labile biomolecular interaction or covalent bond. With the cMBs, the nucleic acid hybridization process can be easily controlled with light, which offers the possibility for a high spatiotemporal resolution study of intracellular mRNAs. © The Royal Society of Chemistry 2011

  4. Detection of Toxoplasma gondii with a DNA molecular beacon probe

    Science.gov (United States)

    Zhou, Cun; Xu, Shichao; Yang, Juan; Zhang, Jimei; Dai, Zhao; Zheng, Guo; Sun, Bo; Sun, Shuqing; Feng, Teilin; Zi, Yan; Liang, Chu; Luo, Hao

    2009-07-01

    Toxoplasma gondii is a kind of microscopic parasite that may infect humans, and there are increasing concerns on the early detection of latent Toxoplasma gondii infection in recent years. This research highlights a new type of molecular beacon (MB) fluorescent probe for Toxoplasma DNA testing. We combined high-efficiency fluorescent inorganic core-shell quantum dots-CdTe/ZnS (as fluorescent energy donor) and BHQ-2 (energy acceptor) to the single-strand DNA of Toxoplasma gondii, and a molecular beacon sensing system based on fluorescence resonance energy transfer (FRET) was achieved. Core-shell quantum dots CdTe/ZnS was firstly prepared in aqueous solution, and the influencing factor of its fluorescent properties, including CdTe/Na2S/Zn(CH3COO)2 (v/v), dependence of reaction time, temperature, and pH, is investigated systematically. The synthesized quantum dots and molecular beacon were characterized by transmission electron microscopy (TEM), ultraviolet-visible spectrophotometer (UV-vis), fluorescent spectrophotometer (FS), respectively. The TEM results showed that CdTe/ZnS core-shell quantum dots is ~11nm in size, and the quantum dots is water-soluble well. The sensing ability of target DNA of assembled MB was investigated, and results showed that the target Toxoplasma gonddi DNA can be successfully detected by measuring the change of fluorescence intensity. The results showed that the current sensing probe will be a useful and convenient tool in Toxoplasma gondii early detection.

  5. High-throughput SNP genotyping: combining tag SNPs and molecular beacons

    CSIR Research Space (South Africa)

    Barreiro, LB

    2009-10-01

    Full Text Available In the last decade, molecular beacons have emerged to become a widely used tool in the multiplex typing of single nucleotide polymorphisms (SNPs). Improvements in detection technologies in instrumentation and chemistries to label these probes have...

  6. Molecular beacon biosensors for DNA/RNA analysis

    Science.gov (United States)

    Fang, Xiaohong; Schuster, Sheldon; Liu, Xiaojing; Correll, Tiffany; Zhang, Peng; Tapec, Ruby; Santra, Swadeshmukul; Qhobosheanne, Monde; Lou, Jane H.; Tan, Weihong

    2000-03-01

    We have developed a variety of novel DNA biosensors using a new class of oligonucleotide probe, molecular beacon (MB). MB has the fluorescence signal transduction mechanism built within the molecules. It can report the presence of specific nucleic acids with high sensitivity and excellent selectivity. Biotinylated MBs have been designed and synthesized for immobilization onto silica surface through avidin-biotin binding. The effect of the avidin-biotin bridge on the MB hybridization has been studied. Our result shows that using streptavidin has less effect than using avidin in MB hybridization. Two kinds of fiber optical DNA sensors have been prepared and characterized: a fiber optic evanescent wave sensor and a submicrometer optical fiber sensor. The sensors are rapid,stable, highly selective, reproducible and regenerable. They have been applied to detect specific DNA and mRNA sequences and to the study of the DNA hybridization kinetics. Silica nanoparticles have also been used for MB immobilization in order to prepare a large quantity of nanometer sized DNA/RNA biosensors.

  7. Analytical performance of molecular beacons on surface immobilized gold nanoparticles of varying size and density.

    Science.gov (United States)

    Uddayasankar, Uvaraj; Krull, Ulrich J

    2013-11-25

    The high quenching efficiency of metal nanoparticles has facilitated its use as quenchers in molecular beacons. To optimize this system, a good understanding of the many factors that influence molecular beacon performance is required. In this study, molecular beacon performance was evaluated as a function of gold nanoparticle size and its immobilization characteristics. Gold nanoparticles of 4 nm, 15 nm and 87 nm diameter, were immobilized onto glass slides. Each size regime offered distinctive optical properties for fluorescence quenching of molecular dyes that were conjugated to oligonucleotides that were immobilized to the gold nanoparticles. Rigid double stranded DNA was used as a model to place fluorophores at different distances from the gold nanoparticles. The effect of particle size and also the immobilization density of nanoparticles was evaluated. The 4 nm and 87 nm gold nanoparticles offered the highest sensitivity in terms of the change in fluorescence intensity as a function of distance (3-fold improvement for Cy5). The optical properties of the molecular fluorophore was of significance, with Cy5 offering higher contrast ratios than Cy3 due to the red-shifted emission spectrum relative to the plasmon peak. A high density of gold nanoparticles reduced contrast ratios, indicating preference for a monolayer of immobilized nanoparticles when considering analytical performance. Molecular beacon probes were then used in place of the double stranded oligonucleotides. There was a strong dependence of molecular beacon performance on the length of a linker used for attachment to the nanoparticle surface. The optimal optical performance was obtained with 4 nm gold nanoparticles that were immobilized as monolayers of low density (5.7×10(11)particles cm(-2)) on glass surfaces. These nanoparticle surfaces offered a 2-fold improvement in analytical performance of the molecular beacons when compared to other nanoparticle sizes investigated. The principles developed

  8. Molecular beacon anchored onto a graphene oxide substrate

    Science.gov (United States)

    Darbandi, Arash; Datta, Debopam; Patel, Krunal; Lin, Gary; Stroscio, Michael A.; Dutta, Mitra

    2017-09-01

    In this article, we report a graphene oxide-based nanosensor incorporating semiconductor quantum dots linked to DNA-aptamers that functions as a ‘turn-off’ fluorescent nanosensor for detection of low concentrations of analytes. A specific demonstration of this turn-off aptasensor is presented for the case of the detection of mercury (II) ions. In this system, ensembles of aptamer-based quantum-dot sensors are anchored onto graphene oxide (GO) flakes which provide a platform for analyte detection in the vicinity of GO. Herein, the operation of this ensemble-based nanosensor is demonstrated for mercury ions, which upon addition of mercury, quenching of the emission intensity from the quantum dots is observed due to resonance energy transfer between quantum dots and the gold nanoparticle connected via a mercury target aptamer. A key result is that the usually dominant effect of quenching of the quantum dot due to close proximity to the GO can be reduced to negligible levels by using a linker molecule in conjunctions with the aptamer-based nanosensor. The effect of ionic concentration of the background matrix on the emission intensity was also investigated. The sensor system is found to be highly selective towards mercury and exhibits a linear behavior (r 2 > 0.99) in the nanomolar concentration range. The detection limit of the sensor towards mercury with no GO present was found to be 16.5 nM. With GO attached to molecular beacon via 14 base, 35 base, and 51 base long linker DNA, the detection limit was found to be 38.4 nM, 9.45 nM, and 11.38 nM; respectively.

  9. Non-linear molecular pattern classification using molecular beacons with multiple targets.

    Science.gov (United States)

    Lee, In-Hee; Lee, Seung Hwan; Park, Tai Hyun; Zhang, Byoung-Tak

    2013-12-01

    In vitro pattern classification has been highlighted as an important future application of DNA computing. Previous work has demonstrated the feasibility of linear classifiers using DNA-based molecular computing. However, complex tasks require non-linear classification capability. Here we design a molecular beacon that can interact with multiple targets and experimentally shows that its fluorescent signals form a complex radial-basis function, enabling it to be used as a building block for non-linear molecular classification in vitro. The proposed method was successfully applied to solving artificial and real-world classification problems: XOR and microRNA expression patterns. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  10. Toxoplasma gondii DNA detection with a magnetic molecular beacon probe

    Science.gov (United States)

    Xu, Shichao; Yao, Cuicui; Wei, Shuoming; Zhang, Jimei; Dai, Zhao; Zheng, Guo; Sun, Bo; Han, Qing; Hu, Fei; Zhou, Hongming

    2008-12-01

    Toxoplasma Gondii infection is widespread in humans worldwide and reported infection rates range from 3%-70%, depending on the populations or geographic areas, and it has been recognized as a potential food safety hazard in our daily life. A magnetic molecular beacon probe (mMBP), based on theory of fluorescence resonance energy transfer (FRET), was currently reported to detect Toxoplasma Gondii DNA. Nano-sized Fe3O4 were primarily prepared by coprecipitation method in aqueous phase with NaOH as precipitator, and was used as magnetic core. The qualified coreshell magnetic quantum dots (mQDs), i.e. CdTe(symbol)Fe3O4, were then achieved by layer-by-layer method when mol ratio of Fe3O4/CdTe is 1/3, pH at 6.0, 30 °C, and reactant solution was refluxed for 30 min, the size of mQDs were determined to be 12-15 nm via transmission electron microscopy (TEM). Over 70% overlap between emission spectrum of mQDs and absorbance spectrum of BHQ-2 was observed, this result suggests the synthesized mQDs and BHQ-2 can be utilized as energy donor and energy acceptor, respectively. The sensing probe was fabricated and a stem-loop Toxoplasma Gondii DNA oligonucleotide was labeled with mQDs at the 5' end and BHQ-2 at 3' end, respectively. Target Toxoplasma gondii DNA was detected under conditions of 37 °C, hybridization for 2h, at pH8.0 in Tris-HCl buffer. About 30% recovery of fluorescence intensity was observed via fluorescence spectrum (FS) after the Toxoplasma gondii DNA was added, which suggested that the Toxoplasma Gondii DNA was successfully detected. Specificity investigation of the mMBP indicated that relative low recovery of fluorescence intensity was obtained when the target DNA with one-base pair mismatch was added, this result indicated the high specificity of the sensing probe. Our research simultaneously indicated that mMBP can be conveniently separated from the unhybridized stem-loop DNA and target DNA, which will be meaningful in DNA sensing and purification process.

  11. Visual detection of multidrug resistance gene in living cell using the molecular beacon imaging

    Science.gov (United States)

    Zhou, Qiumei; Ma, Yi; Gu, Yueqing

    2014-09-01

    A major problem in cancer treatment is the development of resistance to chemotherapeutic agents in tumor cells. Detection of effective prognostic biomarkers and targets are of crucial importance to the management of individualized therapies. However, quantitative analysis of the drug resistance gene had been difficult because of technical limitations. In this study, we designed and used a special hairpin deoxyribonucleic acid (DNA), which served as a beacon for detecting human drug resistance indicater. Upon hybridizing with the target mRNA, the hairpin DNA modified gold nanoparticle beacons (hDAuNP beacons) release the fluorophores attached at 5'end of the oligonucleotide sequence. The fluorescence properties of the beacon before and after the hybridization with the complementary DNA were confirmed in vitro. The hDAuNP beacons could be taken up by living cells with low inherent cytotoxicity and higher stability. hDAuNP beacon imaged by confocal laser scanning microscopy to detect the resistance gene expression. The detected fluorescence in MCF7and MCF7/ADR cells correlates with the specific drug resistance gene expression, which is consistent with the result from Q-PCR. Thus, this approach overcame many of the challenges of previous techniques by creating highly sensitive and effective intracellular probes for monitoring gene expression.

  12. Proteomics in reproductive biology: beacon for unraveling the molecular complexities.

    Science.gov (United States)

    Upadhyay, Rahul D; Balasinor, N H; Kumar, Anita V; Sachdeva, Geetanjali; Parte, Priyanka; Dumasia, Kushaan

    2013-01-01

    Proteomics, an interface of rapidly evolving advances in physics and biology, is rapidly developing and expanding its potential applications to molecular and cellular biology. Application of proteomics tools has contributed towards identification of relevant protein biomarkers that can potentially change the strategies for early diagnosis and treatment of several diseases. The emergence of powerful mass spectrometry-based proteomics technique has added a new dimension to the field of medical research in liver, heart diseases and certain forms of cancer. Most proteomics tools are also being used to study physiological and pathological events related to reproductive biology. There have been attempts to generate the proteomes of testes, sperm, seminal fluid, epididymis, oocyte, and endometrium from reproductive disease patients. Here, we have reviewed proteomics based investigations in humans over the last decade, which focus on delineating the mechanism underlying various reproductive events such as spermatogenesis, oogenesis, endometriosis, polycystic ovary syndrome, embryo development. The challenge is to harness new technologies like 2-DE, DIGE, MALDI-MS, SELDI-MS, MUDPIT, LC-MS etc., to a greater extent to develop widely applicable clinical tools in understanding molecular aspects of reproduction both in health and disease. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Surface-attached molecular beacons light the way for DNA sequencing

    Czech Academy of Sciences Publication Activity Database

    Paleček, Emil

    2004-01-01

    Roč. 22, č. 2 (2004), s. 55-58 ISSN 0167-7799 R&D Projects: GA AV ČR IBS5004355; GA ČR GA204/03/0566 Institutional research plan: CEZ:AV0Z5004920 Keywords : molecular beacon * DNA stem-loop structure * DNA sensors Subject RIV: BO - Biophysics Impact factor: 8.606, year: 2004

  14. A Biofunctional Molecular Beacon for Detecting Single Base Mutations in Cancer Cells

    Directory of Open Access Journals (Sweden)

    Haiyan Dong

    2016-01-01

    Full Text Available The development of a convenient and sensitive biosensing system to detect specific DNA sequences is an important issue in the field of genetic disease therapy. As a classic DNA detection technique, molecular beacon (MB is often used in the biosensing system. However, it has intrinsic drawbacks, including high assay cost, complicated chemical modification, and operational complexity. In this study, we developed a simple and cost-effective label-free multifunctional MB (LMMB by integrating elements of polymerization primer, template, target recognition, and G-quadruplex into one entity to detect target DNA. The core technique was accomplished by introducing a G-hairpin that features fragments of both G-quadruplex and target DNA recognition in the G-hairpin stem. Hybridization between LMMB and target DNA triggered conformational change between the G-hairpin and the common C-hairpin, resulting in significant SYBR-green signal amplification. The hybridization continues to the isothermal circular strand-displacement polymerization and accumulation of the double-stranded fragments, causing the uninterrupted extension of the LMMB without a need of chemical modification and other assistant DNA sequences. The novel and programmable LMMB could detect target DNA with sensitivity at 250 pmol/l with a linear range from 2 to 100 nmol/l and the relative standard deviation of 7.98%. The LMMB could sense a single base mutation from the normal DNA, and polymerase chain reaction (PCR amplicons of the mutant-type cell line from the wild-type one. The total time required for preparation and assaying was only 25 minutes. Apparently, the LMMB shows great potential for detecting DNA and its mutations in biosamples, and therefore it opens up a new prospect for genetic disease therapy.

  15. A novel strategy for human papillomavirus detection and genotyping with SybrGreen and molecular beacon polymerase chain reaction.

    Science.gov (United States)

    Szuhai, K; Sandhaus, E; Kolkman-Uljee, S M; Lemaître, M; Truffert, J C; Dirks, R W; Tanke, H J; Fleuren, G J; Schuuring, E; Raap, A K

    2001-11-01

    Human papillomaviruses (HPVs) play an important role in the pathogenesis of cervical cancer. For identification of the large number of different HPV types found in (pre)malignant lesions, a robust methodology is needed that combines general HPV detection with HPV genotyping. We have developed for formaldehyde-fixed samples a strategy that, in a homogeneous, real-time fluorescence polymerase chain reaction (PCR)-based assay, accomplishes general HPV detection by SybrGreen reporting of HPV-DNA amplicons, and genotyping of seven prevalent HPV types (HPV-6, -11, -16, -18, -31, -33, -45) by real-time molecular beacon PCR. The false-positive rate of the HPV SybrGreen-PCR was 4%, making it well suited as a prescreening, general HPV detection technology. The type specificity of the seven selected HPV molecular beacons was 100% and double infections were readily identified. The multiplexing capacity of the HPV molecular beacon PCR was analyzed and up to three differently labeled molecular beacons could be used in one PCR reaction without observing cross talk. The inherent quantitation capacities of real-time fluorescence PCR allowed the determination of average HPV copy number per cell. We conclude that the HPV SybrGreen-PCR in combination with the HPV molecular beacon PCR provides a robust, sensitive, and quantitative general HPV detection and genotyping methodology.

  16. Enzymatic Amplification of DNA/RNA Hybrid Molecular Beacon Signaling in Nucleic Acid Detection

    OpenAIRE

    Jacroux, Thomas; Rieck, Daniel C.; Cui, Rong; Ouyang, Yexin; Dong, Wen-Ji

    2012-01-01

    A rapid assay operable under isothermal or non-isothermal conditions is described wherein the sensitivity of a typical molecular beacon (MB) system is improved by utilizing thermostable RNase H to enzymatically cleave an MB comprised of a DNA stem and RNA loop (R/D-MB). Upon hybridization of the R/D-MB to target DNA, there was a modest increase in fluorescence intensity (~5.7x above background) due to an opening of the probe and concomitant reduction in the Förster resonance energy transfer e...

  17. A quencher-free molecular beacon design based on pyrene excimer fluorescence using pyrene-labeled UNA (unlocked nucleic acid)

    DEFF Research Database (Denmark)

    Karlsen, Kasper Kannegård; Okholm, Anders Hauge; Kjems, Jørgen

    2013-01-01

    A quencher-free molecular beacon capable of generating pyrene excimer fluorescence has been constructed using strategically positioned pyrene-UNA monomers. Hybridization of a fully complementary RNA target was accompanied by a pyrene excimer emission increase of more than 900%, and detection of R...... in living cells was demonstrated....

  18. Tracking neuronal marker expression inside living differentiating cells using molecular beacons

    DEFF Research Database (Denmark)

    Ilieva, Mirolyuba; Della Vedova, Paolo; Hansen, Ole

    2013-01-01

    Monitoring gene expression is an important tool for elucidating mechanisms of cellular function. In order to monitor gene expression during nerve cell development, molecular beacon (MB) probes targeting markers representing different stages of neuronal differentiation were designed and synthesized...... transfection. The cells will then each contain about 60,000 MBs. Gene expression was detected at different time points using fluorescence microscopy. Nestin and NeuN mRNA were expressed in approximately 35% of the LUHMES cells grown in growth medium, and in 80-90% of cells after differentiation. MAP2...... and tyrosine hydroxylase mRNAs were expressed 2 and 3 days post induction of differentiation, respectively. Oct 4 was not detected with MB in these cells and signal was not increased over time suggesting that MB are generally stable inside the cells. The gene expression changes measured using MBs were...

  19. Theranostic Properties of a Survivin-Directed Molecular Beacon in Human Melanoma Cells

    Science.gov (United States)

    Carpi, Sara; Fogli, Stefano; Giannetti, Ambra; Adinolfi, Barbara; Tombelli, Sara; Da Pozzo, Eleonora; Vanni, Alessia; Martinotti, Enrica; Martini, Claudia; Breschi, Maria Cristina; Pellegrino, Mario

    2014-01-01

    Survivin is an inhibitor of apoptosis overexpressed in different types of tumors and undetectable in most terminally differentiated normal tissues. In the current study, we sought to evaluate the in vitro theranostic properties of a molecular beacon-oligodeoxynucleotide (MB) that targets survivin mRNA. We used laser scanning confocal microscopy to study MB delivery in living cells and real-time PCR and western blot to assess selective survivin-targeting in human malignant melanoma cells. We further assess the pro-apoptotic effect of MB by measuring internucleosomal DNA fragmentation, dissipation of mitochondrial membrane potential (MMP) and changes in nuclear morphology. Transfection of MB into A375 and 501 Mel cells generated high signal intensity from the cytoplasm, while no signal was detected in the extracellular environment and in survivin-negative cells (i.e., human melanocytes and monocytes). MB time dependently decreased survivin mRNA and protein expression in melanoma cells with the maximum effect reached at 72 h. Treatment of melanoma cells with MB induced apoptosis by significant changes in MMP, accumulation of histone-complexed DNA fragments in the cytoplasm and nuclear condensation. MB also enhanced the pro-apoptotic effect of standard chemotherapeutic drugs tested at clinically relevant concentrations. The MB tested in the current study conjugates the ability of imaging with the pharmacological silencing activity against survivin mRNA in human melanoma cells and may represent an innovative approach for cancer diagnosis and treatment. PMID:25501971

  20. Quantification of Salmonella Typhi in water and sediments by molecular-beacon based qPCR.

    Science.gov (United States)

    Rani, Neetika; Vajpayee, Poornima; Bhatti, Saurabh; Singh, Smriti; Shanker, Rishi; Gupta, Kailash Chand

    2014-10-01

    A molecular-beacon based qPCR assay targeting staG gene was designed for specific detection and quantification of S. Typhi and validated against water and sediment samples collected from the river Ganga, Yamuna and their confluence on two days during Mahakumbha mela 2012-2013 (a) 18 December, 2012: before six major religious holy dips (Makar Sankranti, Paush Poornima, Mauni Amavasya, Basant Panchami, Maghi Poornima and Mahashivratri) (b) 10 February, 2013: after the holy dip was taken by over 3,00,00,000 devotees led by ascetics of Hindu sects at Sangam on 'Mauni Amavasya' (the most auspicious day of ritualistic mass bathing). The assay could detect linearly lowest 1 genomic equivalent per qPCR and is highly sensitive and selective for S. Typhi detection in presence of non specific DNA from other bacterial strains including S. Paratyphi A and S. Typhimurium. It has been observed that water and sediment samples exhibit S. Typhi. The mass holy dip by devotees significantly affected the water and sediment quality by enhancing the number of S. Typhi in the study area. The qPCR developed in the study might be helpful in planning the intervention and prevention strategies for control of enteric fever outbreaks in endemic regions. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. A molecular beacon microarray based on a quantum dot label for detecting single nucleotide polymorphisms.

    Science.gov (United States)

    Guo, Qingsheng; Bai, Zhixiong; Liu, Yuqian; Sun, Qingjiang

    2016-03-15

    In this work, we report the application of streptavidin-coated quantum dot (strAV-QD) in molecular beacon (MB) microarray assays by using the strAV-QD to label the immobilized MB, avoiding target labeling and meanwhile obviating the use of amplification. The MBs are stem-loop structured oligodeoxynucleotides, modified with a thiol and a biotin at two terminals of the stem. With the strAV-QD labeling an "opened" MB rather than a "closed" MB via streptavidin-biotin reaction, a sensitive and specific detection of label-free target DNA sequence is demonstrated by the MB microarray, with a signal-to-background ratio of 8. The immobilized MBs can be perfectly regenerated, allowing the reuse of the microarray. The MB microarray also is able to detect single nucleotide polymorphisms, exhibiting genotype-dependent fluorescence signals. It is demonstrated that the MB microarray can perform as a 4-to-2 encoder, compressing the genotype information into two outputs. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. The use of nanocrystal quantum dot as fluorophore reporters in molecular beacon-based assays

    Science.gov (United States)

    Adegoke, Oluwasesan; Park, Enoch Y.

    2016-12-01

    The utilization of molecular beacon (MB) biosensor probes to detect nucleic acid targets has received enormous interest within the scientific community. This interest has been stimulated by the operational qualities of MB-based probes with respect to their unique sensitivity and specificity. The design of MB biosensors entails not only optimizing the sequence of the loop to hybridize with the nucleic acid target or optimization of the length of the stem to tune the sensitivity but also the selection of the appropriate fluorophore reporter to generate the signal transduction read-out upon hybridization of the probe with the target sequence. Traditional organic fluorescent dyes are mostly used for signal reporting in MB assays but their optical properties in comparison to semiconductor fluorescent quantum dot (Qdot) nanocrystals are at a disadvantage. This review highlights the progress made in exploiting Qdot as fluorophore reporters in MB-based assays with the aim of instigating further development in the field of Qdot-MB technology. The development reported to date indicates that unparalleled fluorescence signal reporting in MB-based assays can be achieved using well-constructed Qdot fluorophores.

  3. Electrochemical molecular beacon biosensor for sequence-specific recognition of double-stranded DNA.

    Science.gov (United States)

    Miao, Xiangmin; Guo, Xiaoting; Xiao, Zhiyou; Ling, Liansheng

    2014-09-15

    Direct recognition of double-stranded DNA (dsDNA) was crucial to disease diagnosis and gene therapy, because DNA in its natural state is double stranded. Here, a novel sensor for the sequence-specific recognition of dsDNA was developed based on the structure change of ferrocene (Fc) redox probe modified molecular beacon (MB). For constructing such a sensor, gold nanoparticles (AuNPs) were initially electrochemical-deposited onto glass carbon electrode (GCE) surface to immobilize thiolated MB in their folded states with Au-S bond. Hybridization of MB with target dsDNA induced the formation of parallel triplex DNA and opened the stem-loop structure of it, which resulted in the redox probe (Fc) away from the electrode and triggered the decrease of current signals. Under optimal conditions, dsDNA detection could be realized in the range from 350 pM to 25 nM, with a detection limit of 275 pM. Moreover, the proposed method has good sequence-specificity for target dsDNA compared with single base pair mismatch and two base pairs mismatches. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Chitosan Combined with Molecular Beacon for Mir-155 Detection and Imaging in Lung Cancer

    Directory of Open Access Journals (Sweden)

    Hai-Zhen Zhu

    2014-09-01

    Full Text Available Lung cancer is the major cause of cancer-related deaths worldwide, thus developing effective methods for its early diagnosis is urgently needed. In recent years, microRNAs (miRNAs, miR have been reported to play important roles in carcinogenesis and have become potential biomarkers for cancer diagnosis and treatment. Molecular beacon (MB technology is a universal technology to detect DNA/RNA expression in living cells. As a natural polymers, chitosan (CS nanoparticles could be used as a carrier for safe delivery of nucleic acid. In this study, we developed a probe using nanoparticles of miR-155 MB self assembled with CS (CS-miR-155 MB to image the expression of miR-155 in cancer cells. Hybridization assay showed that the locked nucleic acid (LAN modified miR-155 MB could target miR-155 effectively and sensitively. The miR-155 MB self-assembly with CS nanoparticles formed stable complexes at the proper weight ratio. The CS nanoparticles showed higher fluorescence intensity and transfection efficiency than the lipid-based formulation transfection agent by confocal microscopy and flow cytometry analysis. The CS-MB complexes were found to be easily synthesized and exhibited strong enzymatic stability, efficient cellular uptake, high target selectivity and biocompatibility. The CS-MB complexes can also be applied in other cancers just by simply changing for a targeted miRNA highly expressed in those cancer cells. Therefore, it is a promising vehicle used for detecting miRNA expression in living cells.

  5. Hybridization Efficiency of Molecular Beacons Bound to Gold Nanowires: Effect of Surface Coverage and Target Length

    Science.gov (United States)

    2010-01-01

    Surface-bound nucleic acid probes designed to adopt specific secondary structures are becoming increasingly important in a range of biosensing applications but remain less well characterized than traditional single-stranded probes, which are typically designed to avoid secondary structure. We report the hybridization efficiency for surface-immobilized hairpin DNA probes. Our probes are molecular beacons, carrying a 3′ dye moiety and a 5′ thiol for attachment to gold nanowires, which serve as both scaffolds for probe attachment and quenchers. Hybridization efficiency was dependent on probe surface coverage, reaching a maximum of ∼90% at intermediate coverages of (1−2) × 1012 probes/cm2 and dropping to ≤20% at higher or lower coverages. Fluorescence intensity did not track with the number of target molecules bound, and was highest for high probe coverage despite the lower bound targets per square centimeter. Backfilling with short thiolated oligoethylene glycol spacers increased hybridization efficiency at low hairpin probe coverages (∼(3−4) × 1011 probes/cm2), but not at higher probe coverages (1 × 1012/cm2). We also evaluated the effect of target length by adding up to 50 nonhybridizing nucleotides to the 3′ or 5′ end of the complementary target sequence. Additional nucleotides on the 3′ end of the complementary target sequence (i.e., the end near the nanowire surface) had a much greater impact on hybridization efficiency as compared to nucleotides added to the 5′ end. This work provides guidance in designing sensors in which surface-bound probes designed to adopt secondary structures are used to detect target sequences from solution. PMID:21038880

  6. Photodynamic Molecular Beacons: An Image-Guided Therapeutic Approach to Breast Cancer Vertebral Metastases

    Science.gov (United States)

    2012-03-01

    spinal metastases are predominantly osteolytic (bone destructive), which is associated with an increase in osteo- clast activity.1 Metastasis disrupts...0.001). The distributions and shape of the cells are largely homogeneous after incubation with the beacons, suggesting minimal toxicity (SI Figure S3

  7. A tumor mRNA-mediated bi-photosensitizer molecular beacon as an efficient imaging and photosensitizing agent.

    Science.gov (United States)

    Gao, Yuan; Qiao, Guangming; Zhuo, Linhai; Li, Na; Liu, Ying; Tang, Bo

    2011-05-14

    A bi-photosensitizer molecular beacon (bi-PS MB) is assembled by coupling two PS molecules, respectively, onto the opposite ends of a single MB. The MB can be triggered by a tumor marker-survivin mRNA. Fluorescence and cytotoxic (1)O(2) generation occur effectively in breast cancer cells, but not in normal cells. Compared with a single-PS MB, a bi-PS MB exhibits much-enhanced properties in the signal-to-background ratio and (1)O(2) generation simultaneously. © The Royal Society of Chemistry 2011

  8. A multiplex protein-free lateral flow assay for detection of microRNAs based on unmodified molecular beacons.

    Science.gov (United States)

    Javani, Atefeh; Javadi-Zarnaghi, Fatemeh; Rasaee, Mohammad Javad

    2017-11-15

    Lateral flow assays (LFAs) have promising potentials for point-of-care applications. Recently, many LFAs have been reported that are based on hybridization of oligonucleotide strands. Mostly, biotinylated capture DNAs are immobilized on the surface of a nitrocellulose membrane via streptavidin interactions. During the assay, stable colorful complexes get formed that are visible by naked eyes. Here, we present an inexpensive and unique design of LFA that applies unmodified oligonucleotides at capture lines. The presented LFA do not utilize streptavidin or any other affinity protein. We employ structural switch of molecular beacons (MB) in combination with base stacking hybridization (BSH) phenomenon. The unique design of the reported LFA provided high selectivity for target oligonucleotides. We validated potential applications of the system for detection of DNA mimics of two microRNAs in multiplex assays. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. In vitro RNA release from a human rhinovirus monitored by means of a molecular beacon and chip electrophoresis.

    Science.gov (United States)

    Weiss, Victor U; Bliem, Christina; Gösler, Irene; Fedosyuk, Sofiya; Kratzmeier, Martin; Blaas, Dieter; Allmaier, Günter

    2016-06-01

    Liquid-phase electrophoresis either in the classical capillary format or miniaturized (chip CE) is a valuable tool for quality control of virus preparations and for targeting questions related to conformational changes of viruses during infection. We present an in vitro assay to follow the release of the RNA genome from a human rhinovirus (common cold virus) by using a molecular beacon (MB) and chip CE. The MB, a probe that becomes fluorescent upon hybridization to a complementary sequence, was designed to bind close to the 3' end of the viral genome. Addition of Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), a well-known additive for reduction of bleaching and blinking of fluorophores in fluorescence microscopy, to the background electrolyte increased the sensitivity of our chip CE set-up. Hence, a fast, sensitive and straightforward method for the detection of viral RNA is introduced. Additionally, challenges of our assay will be discussed. In particular, we found that (i) desalting of virus preparations prior to analysis increased the recorded signal and (ii) the MB-RNA complex signal decreased with the time of virus storage at -70 °C. This suggests that 3'-proximal sequences of the viral RNA, if not the whole genome, underwent degradation during storage and/or freezing and thawing. In summary, we demonstrate, for two independent virus batches, that chip electrophoresis can be used to monitor MB hybridization to RNA released upon incubation of the native virus at 56 °C. Graphical Abstract Schematic of the study strategy: RNA released from HRV-A2 is detected by chip electrophoresis through the increase in fluorescence after genom complexation to a cognate molecular beacon.

  10. [Molecular techniques in mycology].

    Science.gov (United States)

    Rodríguez-Tudela, Juan Luis; Cuesta, Isabel; Gómez-López, Alicia; Alastruey-Izquierdo, Ana; Bernal-Martínez, Leticia; Cuenca-Estrella, Manuel

    2008-11-01

    An increasing number of molecular techniques for the diagnosis of fungal infections have been developed in the last few years, due to the growing prevalence of mycoses and the length of time required for diagnosis when classical microbiological methods are used. These methods are designed to resolve the following aspects of mycological diagnosis: a) Identification of fungi to species level by means of sequencing relevant taxonomic targets; b) early clinical diagnosis of invasive fungal infections; c) detection of molecular mechanisms of resistance to antifungal agents; and d) molecular typing of fungi. Currently, these methods are restricted to highly developed laboratories. However, some of these techniques will probably be available in daily clinical practice in the near future.

  11. Determination of mutated genes in the presence of wild-type DNA by using molecular beacons as probe

    Science.gov (United States)

    Zhang, Yonghua; Ai, Junjie; Gu, Qiaorong; Gao, Qiang; Qi, Honglan; Zhang, Chengxiao

    2017-03-01

    Low-abundance mutations in the presence of wild-type DNA can be determined using molecular beacon (MB) as probe. A MB is generally used as DNA probe because it can distinguish single-base mismatched target DNA from fully matched target DNA. However, the probe can not determine low-abundance mutations in the presence of wild-type DNA. In this study, this limitation is addressed by enhancing the stability of unpaired base-containing dsDNA with a hydrogen-bonding ligand, which was added after hybridization of the MB to the target DNA. The ligand formed hydrogen bonds with unpaired bases and stabilized the unpaired base-containing dsDNA if target DNA is mutated one. As a result, more MBs were opened by the mutant genes in the presence of the ligand and a further increase in the fluorescence intensity was obtained. By contrast, fluorescence intensity did not change if target DNA is wild-type one. Consequent increase in the fluorescence intensity of the MB was regarded as a signal derived from mutant genes. The proposed method was applied in synthetic template systems to determine point mutation in DNA obtained from PCR analysis. The method also allows rapid and simple discrimination of a signal if it is originated in the presence of mutant gene or alternatively by a lower concentration of wild gene.

  12. Molecular detection of Phytophthora ramorum by real-time PCR using Taqman, SYBR Green and molecular beacons with three genes

    Science.gov (United States)

    G.J. Bilodeau; C.A. Lévesque; A.W.A.M. De Cock; C. Duchaine; G. Kristjansson; R.C. Hamelin

    2006-01-01

    Sudden oak death, caused by Phytophthora ramorum, is a severe disease that can affect numerous species of trees and shrubs. This pathogen has been spread via nursery stock, and quarantine measures are currently in place to prevent further spread. Molecular assays have been developed to rapidly detect and identify P. ramorum, but...

  13. SOX2 and OCT4 mRNA-Expressing Cells, Detected by Molecular Beacons, Localize to the Center of Neurospheres during Differentiation

    DEFF Research Database (Denmark)

    Ilieva, Mirolyuba; Dufva, Martin

    2013-01-01

    image analysis every day for seven days showed that the OCT4 and SOX2 mRNA-expressing cells clustered in the centre of the neurospheres cultured in differentiation medium. By contrast, cells at the periphery of the differentiating spheres developed neurite outgrowths and expressed the tyrosine...... hydroxylase protein, indicating terminal differentiation. Neurospheres cultured in growth medium contained OCT4 and SOX2-positive cells distributed throughout the entire sphere, and no differentiating neurones. Gene expression of SOX2 and OCT4 mRNA detected by MBs correlated well with gene and protein......Neurospheres are used as in vitro assay to measure the properties of neural stem cells. To investigate the molecular and phenotypic heterogeneity of neurospheres, molecular beacons (MBs) targeted against the stem cell markers OCT4 and SOX2 were designed, and synthesized with a 2'-O-methyl RNA...

  14. Auditory evacuation beacons

    NARCIS (Netherlands)

    Wijngaarden, S.J. van; Bronkhorst, A.W.; Boer, L.C.

    2005-01-01

    Auditory evacuation beacons can be used to guide people to safe exits, even when vision is totally obscured by smoke. Conventional beacons make use of modulated noise signals. Controlled evacuation experiments show that such signals require explicit instructions and are often misunderstood. A new

  15. Continuous monitoring of restriction endonuclease cleavage activity by universal molecular beacon light quenching coupled with real-time polymerase chain reaction.

    Science.gov (United States)

    Li, Xiaomin; Song, Chen; Zhao, Meiping; Li, Yuanzong

    2008-10-01

    We describe a method for sensitive monitoring of restriction endonuclease kinetics and activity by use of a universal molecular beacon (U-MB) coupled with real-time polymerase chain reaction (PCR). The method is used to monitor the progress of DNA cleavage in a sealed reaction tube and offers more accurate and high-throughput detection. The template has a universal tail hybridized with the U-MB and the remaining sequence is complementary to one of the restriction endonuclease digestion products. The U-MB is replaced by the extension of digested product and the fluorescence quenches. With this concept, one universal fluorescence probe can be used in different enzyme analytical systems. In the work described here, homogenous assays were performed with the restriction endonucleases AluI, EcoRI, XhoI, and SacI at smoothly controlled temperature. Cleavage efficiencies were determined, and the potential applications of this method were discussed. Furthermore, the AluI and EcoRI cleavage reactions were monitored online at varying substrate concentrations at the molecular level, and K(m), V(max), and K(cat) values were calculated. The results suggest that U-MB monitoring of restriction endonuclease assays based on real-time PCR will be very useful for high-throughput, sensitive, and precise assays for enzyme activity screening and evolutionary biotechnology analysis.

  16. SOX2 and OCT4 mRNA-expressing cells, detected by molecular beacons, localize to the center of neurospheres during differentiation.

    Directory of Open Access Journals (Sweden)

    Mirolyuba Ilieva

    Full Text Available Neurospheres are used as in vitro assay to measure the properties of neural stem cells. To investigate the molecular and phenotypic heterogeneity of neurospheres, molecular beacons (MBs targeted against the stem cell markers OCT4 and SOX2 were designed, and synthesized with a 2'-O-methyl RNA backbone. OCT4 and SOX2 MBs were transfected into human embryonic mesencephalon derived cells, which spontaneously form neurospheres when grown on poly-L-ornitine/fibronectin matrix and medium complemented with bFGF. OCT4 and SOX2 gene expression were tracked in individual cell using the MBs. Quantitative image analysis every day for seven days showed that the OCT4 and SOX2 mRNA-expressing cells clustered in the centre of the neurospheres cultured in differentiation medium. By contrast, cells at the periphery of the differentiating spheres developed neurite outgrowths and expressed the tyrosine hydroxylase protein, indicating terminal differentiation. Neurospheres cultured in growth medium contained OCT4 and SOX2-positive cells distributed throughout the entire sphere, and no differentiating neurones. Gene expression of SOX2 and OCT4 mRNA detected by MBs correlated well with gene and protein expression measured by qRT-PCR and immunostaining, respectively. These experimental data support the theoretical model that stem cells cluster in the centre of neurospheres, and demonstrate the use of MBs for the spatial localization of specific gene-expressing cells within heterogeneous cell populations.

  17. Rapid genetic typing of diarrheagenic Escherichia coli using a two-tube modified molecular beacon based multiplex real-time PCR assay and its clinical application.

    Science.gov (United States)

    Chen, Qingliang; Shi, Xiaolu; Li, Yinghui; Jiang, Yixiang; Lin, Yiman; Qiu, Yaqun; Li, Qingge; Hu, Qinghua

    2014-07-15

    Diarrheagenic Escherichia coli (DEC), including Enterotoxigenic E.coli (ETEC), Enteroaggregative E.coli (EAEC), Enteropathogenic E.coli (EPEC), Enterohemolysin E.coli (EHEC) and Enteroinvasive E.coli (EIEC) causes diarrhea or hemolytic uremic syndromes among infants and travelers around the world. A rapid, reliable and repeatable method is urgent for identifying DEC so as to provide the reference for responding to diarrheal disease outbreak and the treatment of the diarrheal patients associated with DEC. In this study, specific primers and modified molecular beacon probes of nine specific virulence genes, whose 5'end were added with homo tail sequence, were designed; and a two-tube modified molecular beacon based multiplex real-time PCR (rtPCR) assay for the identification of five Escherichia coli pathotypes, including ETEC, EAEC, EPEC, EHEC and EIEC was developed and optimized. Totally 102 bacterial strains, including 52 reference bacterial strains and 50 clinical strains were detected to confirm whether the target genes selected were specific. Then detection limits of the assay were tested. Lastly, the assay was applied to the detection of 11860 clinical samples to evaluate the specificity and sensitivity of the developed assay compared with the conventional PCR. The target genes were 100% specific as assessed on 102 bacterial strains since no cross-reactions were observed. The detection limits ranged from 88 CFU/mL (EHEC) to 880 CFU/mL (EPEC). Compared with the conventional PCR, the specificity and sensitivity of the multiplex rtPCR was 100% and over 99%, respectively. The coefficient of variation (CV) for each target gene ranged from 0.45% to 1.53%. 171 positive clinical samples were mostly identified as ETEC (n = 111, 64.9%) and EPEC (n = 38, 22.2%), which were the dominating pathotypes of DEC strains. The developed multiplex rtPCR assay for the identification of DEC was high sensitive and specific and could be applied to the rapid identification of

  18. The G-BHQ synergistic effect: Improved double quenching molecular beacons based on guanine and Black Hole Quencher for sensitive simultaneous detection of two DNAs.

    Science.gov (United States)

    Xiang, Dongshan; Li, Fengquan; Wu, Chenyi; Shi, Boan; Zhai, Kun

    2017-11-01

    We designed two double quenching molecular beacons (MBs) with simple structure based on guanine (G base) and Black Hole Quencher (BHQ), and developed a new analytical method for sensitive simultaneous detection of two DNAs by synchronous fluorescence analysis. In this analytical method, carboxyl fluorescein (FAM) and tetramethyl-6-carboxyrhodamine (TAMRA) were respectively selected as fluorophore of two MBs, Black Hole Quencher 1 (BHQ-1) and Black Hole Quencher 2 (BHQ-2) were respectively selected as organic quencher, and three continuous nucleotides with G base were connected to organic quencher (BHQ-1 and BHQ-2). In the presence of target DNAs, the two MBs hybridize with the corresponding target DNAs, the fluorophores are separated from organic quenchers and G bases, leading to recovery of fluorescence of FAM and TAMRA. Under a certain conditions, the fluorescence intensities of FAM and TAMRA all exhibited good linear dependence on their concentration of target DNAs (T1 and T2) in the range from 4 × 10 -10 to 4 × 10 -8 molL -1 (M). The detection limit (3σ, n = 13) of T1 was 3 × 10 -10 M and that of T2 was 2×10 -10 M, respectively. Compared with the existing analysis methods for multiplex DNA with MBs, this proposed method based on double quenching MBs is not only low fluorescence background, short analytical time and low detection cost, but also easy synthesis and good stability of MB probes. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Real-time PCR with molecular beacons provides a highly accurate assay for detection of Tay-Sachs alleles in single cells.

    Science.gov (United States)

    Rice, John E; Sanchez, J Aquiles; Pierce, Kenneth E; Wangh, Lawrence J

    2002-12-01

    The results presented here provide the first single-cell genetic assay for Tay-Sachs disease based on real-time PCR. Individual lymphoblasts were lysed with an optimized lysis buffer and assayed using one pair of primers that amplifies both the wild type and 1278 + TATC Tay-Sachs alleles. The resulting amplicons were detected in real time with two molecular beacons each with a different colored fluorochrome. The kinetics of amplicon accumulation generate objective criteria by which to evaluate the validity of each reaction. The assay had an overall utility of 95%, based on the detection of at least one signal in 235 of the 248 attempted tests and an efficiency of 97%, as 7 of the 235 samples were excluded from further analysis for objective quantitative reasons. The accuracy of the assay was 99.1%, because 228 of 230 samples gave signals consistent with the genotype of the cells. Only two of the 135 heterozygous samples were allele drop-outs, a rate far lower than previously reported for single-cell Tay-Sachs assays using conventional methods of PCR. Copyright 2002 John Wiley & Sons, Ltd.

  20. A modified molecular beacons-based multiplex real-time PCR assay for simultaneous detection of eight foodborne pathogens in a single reaction and its application.

    Science.gov (United States)

    Hu, Qinghua; Lyu, Dongyue; Shi, Xiaolu; Jiang, Yixiang; Lin, Yiman; Li, Yinghui; Qiu, Yaqun; He, Lianhua; Zhang, Ran; Li, Qingge

    2014-03-01

    Foodborne disease outbreaks are often caused by one of the major pathogens. Early identification of the causal pathogen is crucial for disease control and prevention. We describe a real-time polymerase chain reaction (rtPCR) assay that can identify, in a single reaction, up to eight common foodborne bacterial pathogens, including Salmonella enterica subsp. enterica, Listeria monocytogenes, Escherichia coli O157, Vibrio parahaemolyticus, V. vulnificus, Campylobacter jejuni, Enterobacter sakazakii, and Shigella spp. This multiplex rtPCR assay takes advantage of modified molecular beacons and the multicolor combinational probe coding strategy to discriminate each pathogen and the homo-tag assisted non-dimer (HAND) system to prevent dimer formation. The detection limits of the assay ranged from 1.3×10(3) colony-forming units (CFU)/g stool (L. monocytogenes) to 1.6×10(4) CFU/g stool (Shigella spp.). The target genes were 100% specific as assessed on 986 reference strains covering 41 species since no cross-reactions were observed. The assay was applied to the detection of foodborne pathogens in 11,167 clinical samples and the results were compared with culture methods for further validation. The sensitivity and specificity of the rtPCR were 100% and 99%, respectively. When performed in a 96-well rtPCR system, more than 90 samples could be analyzed within 3 h. Given the high accuracy, sensitivity, specificity, and short turn-around time, the established assay could be used for the rapid and reliable identification of the causative pathogens responsible for a certain foodborne disease outbreak and rapid screening of these major foodborne pathogens in laboratory-based surveillance of outpatient clinical samples or even food samples.

  1. Robot-Beacon Distributed Range-Only SLAM for Resource-Constrained Operation.

    Science.gov (United States)

    Torres-González, Arturo; Martínez-de Dios, Jose Ramiro; Ollero, Anibal

    2017-04-20

    This work deals with robot-sensor network cooperation where sensor nodes (beacons) are used as landmarks for Range-Only (RO) Simultaneous Localization and Mapping (SLAM). Most existing RO-SLAM techniques consider beacons as passive devices disregarding the sensing, computational and communication capabilities with which they are actually endowed. SLAM is a resource-demanding task. Besides the technological constraints of the robot and beacons, many applications impose further resource consumption limitations. This paper presents a scalable distributed RO-SLAM scheme for resource-constrained operation. It is capable of exploiting robot-beacon cooperation in order to improve SLAM accuracy while meeting a given resource consumption bound expressed as the maximum number of measurements that are integrated in SLAM per iteration. The proposed scheme combines a Sparse Extended Information Filter (SEIF) SLAM method, in which each beacon gathers and integrates robot-beacon and inter-beacon measurements, and a distributed information-driven measurement allocation tool that dynamically selects the measurements that are integrated in SLAM, balancing uncertainty improvement and resource consumption. The scheme adopts a robot-beacon distributed approach in which each beacon participates in the selection, gathering and integration in SLAM of robot-beacon and inter-beacon measurements, resulting in significant estimation accuracies, resource-consumption efficiency and scalability. It has been integrated in an octorotor Unmanned Aerial System (UAS) and evaluated in 3D SLAM outdoor experiments. The experimental results obtained show its performance and robustness and evidence its advantages over existing methods.

  2. Applications of Molecular Diagnostic Techniques for Infectious ...

    African Journals Online (AJOL)

    Molecular diagnostic techniques involve a variety of techniques that explore the use of nucleic acid molecules for the identification of a particular pathogenic organism. These techniques include nucleic acid-based typing system, nucleic acid analysis without amplification, polymerase chain reaction (PCR) and other nucleic ...

  3. Introduction to basic molecular biologic techniques for molecular imaging researches

    International Nuclear Information System (INIS)

    Kang, Joo Hyun

    2004-01-01

    Molecular imaging is a rapidly growing field due to the advances in molecular biology and imaging technologies. With the introduction of imaging reporter genes into the cell, diverse cellular processes can be monitored, quantified and imaged non-invasively in vivo. These processes include the gene expression, protein-protein interactions, signal transduction pathways, and monitoring of cells such as cancer cells, immune cells, and stem cells. In the near future, molecular imaging analysis will allow us to observe the incipience and progression of the disease. These will make us easier to give a diagnosis in the early stage of intractable diseases such as cancer, neuro-degenerative disease, and immunological disorders. Additionally, molecular imaging method will be a valuable tool for the real-time evaluation of cells in molecular biology and the basic biological studies. As newer and more powerful molecular imaging tools become available, it will be necessary to corporate clinicians, molecular biologists and biochemists for the planning, interpretation, and application of these techniques to their fullest potential. In order for such a multidisciplinary team to be effective, it is essential that a common understanding of basic biochemical and molecular biologic techniques is achieved. Basic molecular techniques for molecular imaging methods are presented in this paper

  4. Improvement of Leukemia diagnose with molecular techniques

    International Nuclear Information System (INIS)

    Campos Rudin, M.E.

    1997-01-01

    The objective of this study was to contribute with new techniques to the clinical diagnosis and to the monitoring of mycloid chronic leukemias in Costa Rica. The same one achieved to determine that is viable to apply radioactive and non reactive methodologies, for the molecular detection of the Philadelphia chromosome.It also found that the application of techniques of cellular biology, helps to classify better the mycloide leukemias and the chronic mycloproliferatives and miclodisplaced disorders. (S. Grainger) [es

  5. Use of molecular techniques in bioremediation.

    Science.gov (United States)

    Płaza, G; Ulfig, K; Hazen, T C; Brigmon, R L

    2001-01-01

    In a practical sense, biotechnology is concerned with the production of commercial products generated by biological processes. More formally, biotechnology may be defined as "the application of scientific and engineering principles to the processing of material by biological agents to provide goods and services" (Cantor, 2000). From a historical perspective, biotechnology dates back to the time when yeast was first used for beer or wine fermentation, and bacteria were used to make yogurt. In 1972, the birth of recombinant DNA technology moved biotechnology to new heights and led to the establishment of a new industry. Progress in biotechnology has been truly remarkable. Within four years of the discovery of recombinant DNA technology, genetically modified organisms (GMOs) were making human insulin, interferon, and human growth hormone. Now, recombinant DNA technology and its products--GMOs are widely used in environmental biotechnology (Glick and Pasternak, 1988; Cowan, 2000). Bioremediation is one of the most rapidly growing areas of environmental biotechnology. Use of bioremediation for environmental clean up is popular due to low costs and its public acceptability. Indeed, bioremediation stands to benefit greatly and advance even more rapidly with the adoption of molecular techniques developed originally for other areas of biotechnology. The 1990s was the decade of molecular microbial ecology (time of using molecular techniques in environmental biotechnology). Adoption of these molecular techniques made scientists realize that microbial populations in the natural environments are much more diverse than previously thought using traditional culture methods. Using molecular ecological methods, such as direct DNA isolation from environmental samples, denaturing gradient gel electrophoresis (DGGE), PCR methods, nucleic acid hybridization etc., we can now study microbial consortia relevant to pollutant degradation in the environment. These techniques promise to

  6. Improvement of molecular techniques: A multidisciplinar vision

    Directory of Open Access Journals (Sweden)

    Bruno do Amaral Crispim

    2016-08-01

    Full Text Available The advances in molecular technologies since the discovery of the PCR (Polymerase Chain Reaction and their association with the use of molecular markers, allowed a rapid progress in the development of technologies and equipment able to generate and analyze data on a large scale, revolutionizing research that until recently was only based on single marker, like the analysis of Single Nucleotide Polymorphism (SNP, and nowadays with the genomic era is already possible in a few hours genotyping millions or even thousands of SNPs. This evolution has allowed improvements in research to the knowledge of genomes creating expectations and real possibilities of application of these techniques in various fields, from medicine to animal production. These new technologies of molecular analysis of DNA variability determining points of interest in chromosomes, which are technically called as molecular markers. These markers can be used in various applications, including paternity test, construction of genetic maps, mapping of quantitative inheritance of characteristics, isolation of genes, marker-assisted selection and characterization of the genetic diversity of different species. The improvement of sequencing and bioinformatics technologies were crucial to studies with characteristics of interest using high-density genetic information. The SNP genotyping panels stimulated researches in the human area, especially in studies of cancer and exoma, and also in agribusiness, aiming the search for superior genotypes for domestic plants and animals. The differential use of the panels is the possibility to seek complex characteristics, once the wide distribution of markers favors through the linkage disequilibrium, the identification of genomic regions associated with expression phenotypes in study. Therefore, this advance has become essential for greater accuracy and speed in molecular diagnostics, increasing the accuracy in the selection of individuals with

  7. Molecular Technique to Understand Deep Microbial Diversity

    Science.gov (United States)

    Vaishampayan, Parag A.; Venkateswaran, Kasthuri J.

    2012-01-01

    Current sequencing-based and DNA microarray techniques to study microbial diversity are based on an initial PCR (polymerase chain reaction) amplification step. However, a number of factors are known to bias PCR amplification and jeopardize the true representation of bacterial diversity. PCR amplification of the minor template appears to be suppressed by the exponential amplification of the more abundant template. It is widely acknowledged among environmental molecular microbiologists that genetic biosignatures identified from an environment only represent the most dominant populations. The technological bottleneck has overlooked the presence of the less abundant minority population, and underestimated their role in the ecosystem maintenance. To generate PCR amplicons for subsequent diversity analysis, bacterial l6S rRNA genes are amplified by PCR using universal primers. Two distinct PCR regimes are employed in parallel: one using normal and the other using biotinlabeled universal primers. PCR products obtained with biotin-labeled primers are mixed with streptavidin-labeled magnetic beads and selectively captured in the presence of a magnetic field. Less-abundant DNA templates that fail to amplify in this first round of PCR amplification are subjected to a second round of PCR using normal universal primers. These PCR products are then subjected to downstream diversity analyses such as conventional cloning and sequencing. A second round of PCR amplified the minority population and completed the deep diversity picture of the environmental sample.

  8. The ANTARES optical beacon system

    Science.gov (United States)

    Ageron, M.; Aguilar, J. A.; Albert, A.; Ameli, F.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardellier-Desages, F.; Aslanides, E.; Aubert, J.-J.; Auer, R.; Barbarito, E.; Basa, S.; Battaglieri, M.; Becherini, Y.; Beltramelli, J.; Bertin, V.; Bigi, A.; Billault, M.; Blaes, R.; de Botton, N.; Bouwhuis, M. C.; Bradbury, S. M.; Bruijn, R.; Brunner, J.; Burgio, G. F.; Busto, J.; Cafagna, F.; Caillat, L.; Calzas, A.; Capone, A.; Caponetto, L.; Carmona, E.; Carr, J.; Cartwright, S. L.; Castel, D.; Castorina, E.; Cavasinni, V.; Cecchini, S.; Ceres, A.; Charvis, P.; Chauchot, P.; Chiarusi, T.; Circella, M.; Colnard, C.; Compère, C.; Coniglione, R.; Cottini, N.; Coyle, P.; Cuneo, S.; Cussatlegras, A.-S.; Damy, G.; van Dantzig, R.; de Bonis, G.; de Marzo, C.; de Vita, R.; Dekeyser, I.; Delagnes, E.; Denans, D.; Deschamps, A.; Destelle, J.-J.; Dinkespieler, B.; Distefano, C.; Donzaud, C.; Drogou, J.-F.; Druillole, F.; Durand, D.; Ernenwein, J.-P.; Escoffier, S.; Falchini, E.; Favard, S.; Fehr, F.; Feinstein, F.; Ferry, S.; Fiorello, C.; Flaminio, V.; Fratini, K.; Fuda, J.-L.; Galeotti, S.; Gallone, J.-M.; Giacomelli, G.; Girard, N.; Gojak, C.; Goret, Ph.; Graf, K.; Hallewell, G.; Harakeh, M. N.; Hartmann, B.; Heijboer, A.; Heine, E.; Hello, Y.; Hernández-Rey, J. J.; Hößl, J.; Hoffman, C.; Hogenbirk, J.; Hubbard, J. R.; Jaquet, M.; Jaspers, M.; de Jong, M.; Jouvenot, F.; Kalantar-Nayestanaki, N.; Kappes, A.; Karg, T.; Katz, U.; Keller, P.; Kok, E.; Kok, H.; Kooijman, P.; Kopper, C.; Korolkova, E. V.; Kouchner, A.; Kretschmer, W.; Kruijer, A.; Kuch, S.; Kudryavstev, V. A.; Lagier, P.; Lahmann, R.; Lamanna, G.; Lamare, P.; Lambard, G.; Languillat, J.-C.; Laschinsky, H.; Lavalle, J.; Le Guen, Y.; Le Provost, H.; Le van Suu, A.; Lefèvre, D.; Legou, T.; Lelaizant, G.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Louis, F.; Lucarelli, F.; Lyashuk, V.; Marcelin, M.; Margiotta, A.; Masullo, R.; Mazéas, F.; Mazure, A.; McMillan, J. E.; Megna, R.; Melissas, M.; Migneco, E.; Milovanovic, A.; Mongelli, M.; Montaruli, T.; Morganti, M.; Moscoso, L.; Musumeci, M.; Naumann-Godo, M.; Naumann, C.; Niess, V.; Noble, T.; Olivetto, C.; Ostasch, R.; Palanque-Delabrouille, N.; Payre, P.; Peek, H.; Perez, A.; Petta, C.; Piattelli, P.; Pillet, R.; Pineau, J.-P.; Poinsignon, J.; Popa, V.; Pradier, T.; Racca, C.; Randazzo, N.; van Randwijk, J.; Real, D.; van Rens, B.; Réthoré, F.; Rewiersma, P.; Riccobene, G.; Rigaud, V.; Ripani, M.; Roca, V.; Roda, C.; Rolin, J. F.; Rose, H. J.; Rostovtsev, A.; Roux, J.; Ruppi, M.; Russo, G. V.; Rusydi, G.; Salesa, F.; Salomon, K.; Sapienza, P.; Schmitt, F.; Schuller, J.-P.; Shanidze, R.; Sokalski, I.; Spona, T.; Spurio, M.; van der Steenhoven, G.; Stolarczyk, T.; Streeb, K.; Sulak, L.; Taiuti, M.; Tamburini, C.; Tao, C.; Terreni, G.; Thompson, L. F.; Urbano, F.; Valdy, P.; Valente, V.; Vallage, B.; Vaudaine, G.; Venekamp, G.; Verlaat, B.; Vernin, P.; de Vries-Uiterweerd, G.; van Wijk, R.; Wijnker, G.; de Witt Huberts, P.; Wobbe, G.; de Wolf, E.; Yao, A.-F.; Zaborov, D.; Zaccone, H.; Zornoza, J. D.; Zúñiga, J.

    2007-08-01

    ANTARES is a neutrino telescope being deployed in the Mediterranean Sea. It consists of a three-dimensional array of photomultiplier tubes that can detect the Cherenkov light induced by charged particles produced in the interactions of neutrinos with the surrounding medium. High angular resolution can be achieved, in particular, when a muon is produced, provided that the Cherenkov photons are detected with sufficient timing precision. Considerations of the intrinsic time uncertainties stemming from the transit time spread in the photomultiplier tubes and the mechanism of transmission of light in sea water lead to the conclusion that a relative time accuracy of the order of 0.5 ns is desirable. Accordingly, different time calibration systems have been developed for the ANTARES telescope. In this article, a system based on Optical Beacons, a set of external and well-controlled pulsed light sources located throughout the detector, is described. This calibration system takes into account the optical properties of sea water, which is used as the detection volume of the ANTARES telescope. The design, tests, construction and first results of the two types of beacons, LED and laser-based, are presented.

  9. A Measurement Study of BLE iBeacon and Geometric Adjustment Scheme for Indoor Location-Based Mobile Applications

    Directory of Open Access Journals (Sweden)

    Jeongyeup Paek

    2016-01-01

    Full Text Available Bluetooth Low Energy (BLE and the iBeacons have recently gained large interest for enabling various proximity-based application services. Given the ubiquitously deployed nature of Bluetooth devices including mobile smartphones, using BLE and iBeacon technologies seemed to be a promising future to come. This work started off with the belief that this was true: iBeacons could provide us with the accuracy in proximity and distance estimation to enable and simplify the development of many previously difficult applications. However, our empirical studies with three different iBeacon devices from various vendors and two types of smartphone platforms prove that this is not the case. Signal strength readings vary significantly over different iBeacon vendors, mobile platforms, environmental or deployment factors, and usage scenarios. This variability in signal strength naturally complicates the process of extracting an accurate location/proximity estimation in real environments. Our lessons on the limitations of iBeacon technique lead us to design a simple class attendance checking application by performing a simple form of geometric adjustments to compensate for the natural variations in beacon signal strength readings. We believe that the negative observations made in this work can provide future researchers with a reference on how well of a performance to expect from iBeacon devices as they enter their system design phases.

  10. An Adaptive Scheme for Robot Localization and Mapping with Dynamically Configurable Inter-Beacon Range Measurements

    Directory of Open Access Journals (Sweden)

    Arturo Torres-González

    2014-04-01

    Full Text Available This work is motivated by robot-sensor network cooperation techniques where sensor nodes (beacons are used as landmarks for range-only (RO simultaneous localization and mapping (SLAM. This paper presents a RO-SLAM scheme that actuates over the measurement gathering process using mechanisms that dynamically modify the rate and variety of measurements that are integrated in the SLAM filter. It includes a measurement gathering module that can be configured to collect direct robot-beacon and inter-beacon measurements with different inter-beacon depth levels and at different rates. It also includes a supervision module that monitors the SLAM performance and dynamically selects the measurement gathering configuration balancing SLAM accuracy and resource consumption. The proposed scheme has been applied to an extended Kalman filter SLAM with auxiliary particle filters for beacon initialization (PF-EKF SLAM and validated with experiments performed in the CONET Integrated Testbed. It achieved lower map and robot errors (34% and 14%, respectively than traditional methods with a lower computational burden (16% and similar beacon energy consumption.

  11. Rapid molecular technique to distinguish Fusarium species

    CSIR Research Space (South Africa)

    Lodolo, EJ

    1993-03-01

    Full Text Available The nuclear DNA (nDNA) of different isolates of three closely related, toxin-producing Fusarium species, F. moniliforme, F. nygamai and F. napiforme, was compared to ascertain the sensitivity of a molecular method to distinguish these three species...

  12. Molecular biology techniques and applications for ocean sensing

    Directory of Open Access Journals (Sweden)

    J. P. Zehr

    2009-05-01

    Full Text Available The study of marine microorganisms using molecular biological techniques is now widespread in the ocean sciences. These techniques target nucleic acids which record the evolutionary history of microbes, and encode for processes which are active in the ocean today. Molecular techniques can form the basis of remote instrumentation sensing technologies for marine microbial diversity and ecological function. Here we review some of the most commonly used molecular biological techniques. These techniques include the polymerase chain reaction (PCR and reverse-transcriptase PCR, quantitative PCR, whole assemblage "fingerprinting" approaches (based on nucleic acid sequence or length heterogeneity, oligonucleotide microarrays, and high-throughput shotgun sequencing of whole genomes and gene transcripts, which can be used to answer biological, ecological, evolutionary and biogeochemical questions in the ocean sciences. Moreover, molecular biological approaches may be deployed on ocean sensor platforms and hold promise for tracking of organisms or processes of interest in near-real time.

  13. Molecular biology techniques and applications for ocean sensing

    Science.gov (United States)

    Zehr, J. P.; Hewson, I.; Moisander, P.

    2009-05-01

    The study of marine microorganisms using molecular biological techniques is now widespread in the ocean sciences. These techniques target nucleic acids which record the evolutionary history of microbes, and encode for processes which are active in the ocean today. Molecular techniques can form the basis of remote instrumentation sensing technologies for marine microbial diversity and ecological function. Here we review some of the most commonly used molecular biological techniques. These techniques include the polymerase chain reaction (PCR) and reverse-transcriptase PCR, quantitative PCR, whole assemblage "fingerprinting" approaches (based on nucleic acid sequence or length heterogeneity), oligonucleotide microarrays, and high-throughput shotgun sequencing of whole genomes and gene transcripts, which can be used to answer biological, ecological, evolutionary and biogeochemical questions in the ocean sciences. Moreover, molecular biological approaches may be deployed on ocean sensor platforms and hold promise for tracking of organisms or processes of interest in near-real time.

  14. Molecular techniques in phytoplankton research: from allozyme electrophoresis to genomics

    NARCIS (Netherlands)

    De Bruin, A.; Ibelings, B.W.; Van Donk, E.

    2003-01-01

    Molecular techniques have become a valuable tool in phytoplankton studies over the past decades. The appropriate choice of a technique from an increasing array of methods can be rather complex, because different techniques are suitable for different questions or problems in ecology and evolution.

  15. Contention Window Analysis for Beaconing in VANETs

    OpenAIRE

    Reinders, René; van Eenennaam, Martijn; Karagiannis, Georgios; Heijenk, Geert

    2011-01-01

    The recently standardised IEEE 802.11p Wireless Access in Vehicular Environment (WAVE) protocol is envisioned to be used for Vehicle-to-Vehicle and Vehicle-to-Infrastructure communications. We provide an analysis of 802.11p’s performance when used for the exchange of small status messages known as beacons. These beacons enable vehicles to establish a Cooperative Awareness from which many applications can draw their inputs. Applications have been proposed to increase safety, efficiency and com...

  16. Multiple beacons for supporting lunar landing navigation

    Science.gov (United States)

    Theil, Stephan; Bora, Leonardo

    2018-02-01

    The exploration and potential future exploitation of solar system bodies requires technologies for precise and safe landings. Current navigation systems for landing probes are relying on a combination of inertial and optical sensor measurements to determine the current flight state with respect to the target body and the desired landing site. With a future transition from single exploration missions to more frequent first exploration and then exploitation missions, the implementation and operation of these missions changes, since it can be expected that a ground infrastructure on the target body is available in the vicinity of the landing site. In a previous paper, the impact of a single ground-based beacon on the navigation performance was investigated depending on the type of radiometric measurements and on the location of the beacon with respect to the landing site. This paper extends this investigation on options for ground-based multiple beacons supporting the on-board navigation system. It analyzes the impact on the achievable navigation accuracy. For that purpose, the paper introduces briefly the existing navigation architecture based on optical navigation and its extension with radiometric measurements. The same scenario of lunar landing as in the previous paper is simulated. The results are analyzed and discussed. They show a single beacon at a large distance along the landing trajectory and multiple beacons close to the landing site can improve the navigation performance. The results show how large the landing area can be increased where a sufficient navigation performance is achieved using the beacons.

  17. Deep sea AUV navigation using multiple acoustic beacons

    Science.gov (United States)

    Ji, Da-xiong; Song, Wei; Zhao, Hong-yu; Liu, Jian

    2016-04-01

    Navigation is a critical requirement for the operation of Autonomous Underwater Vehicles (AUVs). To estimate the vehicle position, we present an algorithm using an extended Kalman filter (EKF) to integrate dead-reckoning position with acoustic ranges from multiple beacons pre-deployed in the operating environment. Owing to high latency, variable sound speed multipath transmissions and unreliability in acoustic measurements, outlier recognition techniques are proposed as well. The navigation algorithm has been tested by the recorded data of deep sea AUV during field operations in a variety of environments. Our results show the improved performance over prior techniques based on position computation.

  18. Beach Advisory and Closing Online Notification (BEACON) system

    Data.gov (United States)

    U.S. Environmental Protection Agency — Beach Advisory and Closing Online Notification system (BEACON) is a colletion of state and local data reported to EPA about beach closings and advisories. BEACON is...

  19. A Brief Review of Molecular Techniques to Assess Plant Diversity

    Directory of Open Access Journals (Sweden)

    Ibrahim A. Arif

    2010-05-01

    Full Text Available Massive loss of valuable plant species in the past centuries and its adverse impact on environmental and socioeconomic values has triggered the conservation of plant resources. Appropriate identification and characterization of plant materials is essential for the successful conservation of plant resources and to ensure their sustainable use. Molecular tools developed in the past few years provide easy, less laborious means for assigning known and unknown plant taxa. These techniques answer many new evolutionary and taxonomic questions, which were not previously possible with only phenotypic methods. Molecular techniques such as DNA barcoding, random amplified polymorphic DNA (RAPD, amplified fragment length polymorphism (AFLP, microsatellites and single nucleotide polymorphisms (SNP have recently been used for plant diversity studies. Each technique has its own advantages and limitations. These techniques differ in their resolving power to detect genetic differences, type of data they generate and their applicability to particular taxonomic levels. This review presents a basic description of different molecular techniques that can be utilized for DNA fingerprinting and molecular diversity analysis of plant species.

  20. A Brief Review of Molecular Techniques to Assess Plant Diversity

    Science.gov (United States)

    Arif, Ibrahim A.; Bakir, Mohammad A.; Khan, Haseeb A.; Al Farhan, Ahmad H.; Al Homaidan, Ali A.; Bahkali, Ali H.; Sadoon, Mohammad Al; Shobrak, Mohammad

    2010-01-01

    Massive loss of valuable plant species in the past centuries and its adverse impact on environmental and socioeconomic values has triggered the conservation of plant resources. Appropriate identification and characterization of plant materials is essential for the successful conservation of plant resources and to ensure their sustainable use. Molecular tools developed in the past few years provide easy, less laborious means for assigning known and unknown plant taxa. These techniques answer many new evolutionary and taxonomic questions, which were not previously possible with only phenotypic methods. Molecular techniques such as DNA barcoding, random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), microsatellites and single nucleotide polymorphisms (SNP) have recently been used for plant diversity studies. Each technique has its own advantages and limitations. These techniques differ in their resolving power to detect genetic differences, type of data they generate and their applicability to particular taxonomic levels. This review presents a basic description of different molecular techniques that can be utilized for DNA fingerprinting and molecular diversity analysis of plant species. PMID:20559503

  1. Multialkali photocathodes grown by molecular beam epitaxy technique

    Science.gov (United States)

    Dubovoi, I. A.; Chernikov, A. S.; Prokhorov, Alexander M.; Schelev, Mikhail Y.; Ushakov, Victor N.

    1991-04-01

    A new technique of bialkali photocathodes growth by molecular beam epitaxy (MI3E) has been developed. The photocathode film was deposited onto the substrate from molecular beams produced by simultaneously operating molecular sources of Sb, Na and K. Thus suggested procedure is noticeably differed from the classical one. Growth rate was about 1 A/sec and complete cycle of photocathode fabrication was 15-20 minutes. A special ultra high vacuum (UHV) chamber for MBE of multialkali photocathodes has been designed. The chamber is a part of UHV system consisting of an analysis vessel supplied with Auger and ESCA electron spectrometer and low energy electron diffractometer (LEED), the MBE chamber itself and a chamber for cold sealing of photocathodes with device body through indium ring. The system gives a possibility to carry out investigations of multialkali photocathode physics and to produce commercial devices. Developed technique can be used for fabrication of vacuum devices including streak tubes.

  2. Técnicas moleculares aplicadas à microbiologia de alimentos = Molecular techniques applied to food microbiology

    Directory of Open Access Journals (Sweden)

    Eliezer Ávila Gandra

    2008-01-01

    Full Text Available A partir da década de 80, as técnicas moleculares começaram a ser utilizadas como uma alternativa aos métodos fenotípicos, tradicionalmente, utilizados em microbiologia de alimentos. Foi acelerada esta substituição com advento da descoberta da reação em cadeia da polimerase (polymerase chain reaction – PCR. Este artigo tem por objetivo revisar as principais técnicas moleculares utilizadas como ferramentas na microbiologia de alimentos, desde as, inicialmente, desenvolvidas, como a análise do perfil plasmidial, até as mais contemporâneas como o PCR em tempo real, discutindo as características, vantagens e desvantagens destas técnicas, avaliando a potencialidade destas para suprir as limitações das técnicas tradicionais.Beginning in the 1980s, molecular techniques became an alternative to the traditionally used phenotypic methods in food microbiology. With the advent of the polymerase chain reaction technique, this substitution was speed up. This article had as objective to review the main molecular techniques used as tools in food microbiology, from plasmidial profile analysis to contemporary techniques such as the real-time PCR. The characteristics, advantages anddisadvantages of these techniques are discussed, by evaluating the potential of these techniques to overcome the limitations of traditional techniques.

  3. APPLICATIONS OF MOLECULAR DISTILLATION TECHNIQUE IN FOOD PRODUCTS

    Directory of Open Access Journals (Sweden)

    O. Ketenoglu

    2015-09-01

    Full Text Available There are several separation techniques -including conventional distillation- for extracting heat sensitive compounds from food products. However, some compounds may have high boiling points at which other compounds might be adversely affected. Vacuum application is also needed for such kinds of foods. Molecular distillation is an advanced vacuum distillation method performed by short-path evaporators. Distance between evaporator and condenser is extremely reduced which results in minimized pressure drop. Heat sensitive material meets heat for a shorttime under high vacuum, thus low or no decomposition occurs. This review aims to discuss the basics and uses of molecular distillation in foods.

  4. Moment techniques in atomic and molecular scattering theory

    International Nuclear Information System (INIS)

    Reinhardt, W.P.

    1980-01-01

    Moment techniques have recently been shown to be useful in ab initio calculation of atomic and molecular continuum processes. We illustrate these methods in a discussion of the photoeffect in hydrogen (H) and H - , and in a discussion of e + -H scattering. As further illustrations of the utility of moments in non-relativistic scattering we consider their use in extracting information from classical trajectory treatments of molecular collisions, and their phenomenological application in correlating experimental data via the information theory approach of Bernstein and Levine

  5. Molecular biology - Part I: Techniques, terminology, and concepts

    International Nuclear Information System (INIS)

    Brown, J. Martin

    1996-01-01

    Purpose/Objective: One of the barriers to understanding modern molecular biology is the lack of a clear understanding of the relevant terminology, techniques, and concepts. This refresher course is intended to address these deficiencies starting from a basic level. The lecture will cover many of the common uses of recombinant DNA, including gene cloning and manipulation. The goal is to enable the nonspecialist to increase his or her understanding of molecular biology in order to more fully enjoy reading current publications and/or listening seminars. Radiation biologists trying to understand a little more molecular biology should also benefit. The following concepts will be among those explained and illustrated: restriction endonucleases, gel electrophoresis, gene cloning, use of vectors such as plasmids, bacteriophage, cosmids and viruses, cDNA and genomic libraries, Southern, Northern, and Western blotting, fluorescent in situ hybridization, polymerase chain reaction (PCR), gel retardation, and reporter gene assays

  6. Double-edge molecular technique for Doppler lidar wind measurement

    Science.gov (United States)

    Flesia, Cristina; Korb, C. L.

    1998-08-01

    The double-edge lidar technique for measuring the wind based upon using molecular backscatter is described. The technique uses two high spectral resolution edge filters which are located in the wings of the Rayleigh-Brillouin profile. This doubles the signal change per unit Doppler shift, the sensitivity, and gives nearly a factor of two improvement in measurement accuracy relative to the single edge technique. The use of a crossover region is described where the sensitivity of a molecular and aerosol-based measurement are equal. This desensitizes the molecular measurement to the effects of aerosol scattering over a frequency range of plus or minus 100 m/s. We give methods for correcting for short- term, shot to shot, frequency jitter and drift using a laser reference frequency measurement and methods for long-term frequency correction using a servo control system. The effects of Rayleigh-Brillouin scattering on the measurement are shown to be significant and are included in the analysis. Simulations for a conical scanning satellite-based lidar at 355 nm show an accuracy of 2 - 3 m/s for altitudes of 2 to 15 km for a 1 km vertical resolution, a satellite altitude of 400 km and a 200 km X 200 km spatial resolution. Results for recent wind measurements, which show an accuracy of 1 m/s up to an altitude of 10 km, are given.

  7. Molecular Diode Studies Based on a Highly Sensitive Molecular Measurement Technique.

    Science.gov (United States)

    Iwane, Madoka; Fujii, Shintaro; Kiguchi, Manabu

    2017-04-26

    In 1974, molecular electronics pioneers Mark Ratner and Arieh Aviram predicted that a single molecule could act as a diode, in which electronic current can be rectified. The electronic rectification property of the diode is one of basic functions of electronic components and since then, the molecular diode has been investigated as a first single-molecule device that would have a practical application. In this review, we first describe the experimental fabrication and electronic characterization techniques of molecular diodes consisting of a small number of molecules or a single molecule. Then, two main mechanisms of the rectification property of the molecular diode are discussed. Finally, representative results for the molecular diode are reviewed and a brief outlook on crucial issues that need to be addressed in future research is discussed.

  8. Application of molecular techniques to crop mutation breeding in Vietnam

    Energy Technology Data Exchange (ETDEWEB)

    Tran Duy Quy [Agricultural Genetics Institute, Tuliem, Hanoi (Viet Nam)

    2002-02-01

    The molecular markers have been effectively applied in mutation breeding, recently. The studies have been mainly looked for the differences at genome structure level between original variety and mutant lines. Many genes have been identified and tagged with various kinds of molecular markers. Studies on gene tagging can provide the information on the number of genes controlling characters and the map location of those genes. The mapped genes have been used to pyramid into crops via marker aided selection (MAS). Many genes were cloned from different creatures, some genes controlling good agronomic traits. In Vietnam, many crops have been released and popularly grown by the farmers, via mutation breeding. However, almost all of the mutation breeding varieties only selected based on morphological parameters which much depended on the environmental conditions, plant physiological status and stage of gene expression. In order to resolve the limitations when using traditional methods, we have planned to apply the molecular techniques to characterize the mutant genotypes obtained in mutation breeding. In this study, we carried out to analyze mutant genotypes of soybean, green pea and map TGMS gene in mutant rice line using molecular techniques. Three markers were mainly used to comprise RFLP, AFLP, and RAPD. RFLP and AFLP markers were used to map TGMS gene that located in genome of the TGMS-1 mutant rice line, and RAPD markers helped to analyze the mutant genome of soybean and green pea lines. Based on the result of study, we concluded that the TGMS gene located on chromosome 2. Application of molecular markers to crop breeding is a necessary and effective approach in Vietnam. (M. Suetake)

  9. The isolated Leptospira Spp. Identification by molecular biological techniques

    Directory of Open Access Journals (Sweden)

    Duangjai Suwancharoen

    2017-01-01

    Full Text Available Leptospirosis is a zoonotic disease caused by the bacteria of Leptospira spp. Identification of this bacterium relies on serotyping and genotyping. Data base for animal causative serovars in Thailand is limited. As the unknown serovars are found in the laboratory, they need to be sent overseas for referent identification. To reduce the cost, this research intended to develop a leptospiral identification method which is user–friendly and able to classify efficiently. Ten Leptospira isolations were cultured from urine samples. They were identified by three molecular biological techniques, including Pulsed-Field Gel Electrophoresis (PFGE, Variable Number Tandem Repeat (VNTR and Multilocus Sequence Typing (MLST. These methods were developed and compared to find the most suitable one for leptospiral identification. VNTR was found to be inappropriate since it could not identify the agents and it did not show the PCR product. PFGE and MLST gave the same results of the unknown 1 and 2 which were L.weilii sv Samin st Samin. Unknown 4 showed different results by each technique. Unknown 5 to 10 were likely to be L.meyeri sv Ranarum st ICF and Leptonema illini sv Illini st 3055 by PFGE but MLST could not identify the serovar. However, molecular biological technique for Leptospira identification should be done by several methods in order to confirm the result of each other.

  10. Toolbox of Molecular Techniques for Studying Leptospira Spp.

    Science.gov (United States)

    Picardeau, Mathieu

    2017-08-29

    This chapter covers the progress made in the Leptospira field since the application of mutagenesis techniques and how they have allowed the study of virulence factors and, more generally, the biology of Leptospira. The last decade has seen advances in our ability to perform molecular genetic analysis of Leptospira. Major achievements include the generation of large collections of mutant strains and the construction of replicative plasmids, enabling complementation of mutations. However, there are still no practical tools for routine genetic manipulation of pathogenic Leptospira strains, slowing down advances in pathogenesis research. This review summarizes the status of the molecular genetic toolbox for Leptospira species and highlights new challenges in the nascent field of Leptospira genetics.

  11. Double-Edge Molecular Technique for Doppler Lidar Wind Measurement

    Science.gov (United States)

    Flesia, Cristina; Korb, C. Laurence

    1998-01-01

    The double-edge lidar technique for measuring the wind using molecular backscatter is described. Two high spectral resolution edge filters are located in the wings of the Rayleigh-Brillouin profile. This doubles the signal change per unit Doppler shift, the sensitivity, and gives nearly a factor of two improvement in measurement accuracy. The use of a crossover region is described where the sensitivity of a molecular and aerosol-based measurement are equal. This desensitizes the molecular measurement to the effects of aerosol scattering over a frequency range of +/- 100 m/s. We give methods for correcting for short-term frequency jitter and drift using a laser reference frequency measurement and methods for long-term frequency correction using a servo control system. The effects of Rayleigh-Brillouin scattering on the measurement are shown to be significant and are included in the analysis. Simulations for a conical scanning satellite-based lidar at 355 nm show an accuracy of 2-3 m/s for altitudes of 2 to 15 km for a 1 km vertical resolution, a satellite altitude of 400 km and a 200 km x 200 km spatial resolution. Results of ground based wind measurements are presented.

  12. Determining Locations by Use of Networks of Passive Beacons

    Science.gov (United States)

    Okino, Clayton; Gray, Andrew; Jennings, Esther

    2009-01-01

    Networks of passive radio beacons spanning moderate-sized terrain areas have been proposed to aid navigation of small robotic aircraft that would be used to explore Saturn s moon Titan. Such networks could also be used on Earth to aid navigation of robotic aircraft, land vehicles, or vessels engaged in exploration or reconnaissance in situations or locations (e.g., underwater locations) in which Global Positioning System (GPS) signals are unreliable or unavailable. Prior to use, it would be necessary to pre-position the beacons at known locations that would be determined by use of one or more precise independent global navigation system(s). Thereafter, while navigating over the area spanned by a given network of passive beacons, an exploratory robot would use the beacons to determine its position precisely relative to the known beacon positions (see figure). If it were necessary for the robot to explore multiple, separated terrain areas spanned by different networks of beacons, the robot could use a long-haul, relatively coarse global navigation system for the lower-precision position determination needed during transit between such areas. The proposed method of precise determination of position of an exploratory robot relative to the positions of passive radio beacons is based partly on the principles of radar and partly on the principles of radio-frequency identification (RFID) tags. The robot would transmit radar-like signals that would be modified and reflected by the passive beacons. The distance to each beacon would be determined from the roundtrip propagation time and/or round-trip phase shift of the signal returning from that beacon. Signals returned from different beacons could be distinguished by means of their RFID characteristics. Alternatively or in addition, the antenna of each beacon could be designed to radiate in a unique pattern that could be identified by the navigation system. Also, alternatively or in addition, sets of identical beacons could

  13. Molecular genetic techniques for gene manipulation in Candida albicans

    Science.gov (United States)

    Xu, Qiu-Rong; Yan, Lan; Lv, Quan-Zhen; Zhou, Mi; Sui, Xue; Cao, Yong-Bing; Jiang, Yuan-Ying

    2014-01-01

    Candida albicans is one of the most common fungal pathogen in humans due to its high frequency as an opportunistic and pathogenic fungus causing superficial as well as invasive infections in immunocompromised patients. An understanding of gene function in C. albicans is necessary to study the molecular basis of its pathogenesis, virulence and drug resistance. Several manipulation techniques have been used for investigation of gene function in C. albicans, including gene disruption, controlled gene expression, protein tagging, gene reintegration, and overexpression. In this review, the main cassettes containing selectable markers used for gene manipulation in C. albicans are summarized; the advantages and limitations of these cassettes are discussed concerning the influences on the target gene expression and the virulence of the mutant strains. PMID:24759671

  14. 78 FR 75392 - American Beacon Funds, et al.; Notice of Application

    Science.gov (United States)

    2013-12-11

    ... Asset Management LLC; (b) American Beacon Balanced Fund--the Manager, Barrow, Hanley, Mewhinney... Beacon Funds, et al.; Notice of Application December 5, 2013. AGENCY: Securities and Exchange Commission...) (order). Applicants: American Beacon Funds and American Beacon Select Funds (collectively, the ``Trusts...

  15. Molecular techniques to interrogate and edit the Chlamydomonas nuclear genome.

    Science.gov (United States)

    Jinkerson, Robert E; Jonikas, Martin C

    2015-05-01

    The success of the green alga Chlamydomonas reinhardtii as a model organism is to a large extent due to the wide range of molecular techniques that are available for its characterization. Here, we review some of the techniques currently used to modify and interrogate the C. reinhardtii nuclear genome and explore several technologies under development. Nuclear mutants can be generated with ultraviolet (UV) light and chemical mutagens, or by insertional mutagenesis. Nuclear transformation methods include biolistic delivery, agitation with glass beads, and electroporation. Transforming DNA integrates into the genome at random sites, and multiple strategies exist for mapping insertion sites. A limited number of studies have demonstrated targeted modification of the nuclear genome by approaches such as zinc-finger nucleases and homologous recombination. RNA interference is widely used to knock down expression levels of nuclear genes. A wide assortment of transgenes has been successfully expressed in the Chlamydomonas nuclear genome, including transformation markers, fluorescent proteins, reporter genes, epitope tagged proteins, and even therapeutic proteins. Optimized expression constructs and strains help transgene expression. Emerging technologies such as the CRISPR/Cas9 system, high-throughput mutant identification, and a whole-genome knockout library are being developed for this organism. We discuss how these advances will propel future investigations. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  16. Do rufous hummingbirds (Selasphorus rufus) use visual beacons?

    Science.gov (United States)

    Hurly, T Andrew; Franz, Simone; Healy, Susan D

    2010-03-01

    Animals are often assumed to use highly conspicuous features of a goal to head directly to that goal ('beaconing'). In the field it is generally assumed that flowers serve as beacons to guide pollinators. Artificial hummingbird feeders are coloured red to serve a similar function. However, anecdotal reports suggest that hummingbirds return to feeder locations in the absence of the feeder (and thus the beacon). Here we test these reports for the first time in the field, using the natural territories of hummingbirds and manipulating flowers on a scale that is ecologically relevant to the birds. We compared the predictions from two distinct hypotheses as to how hummingbirds might use the visual features of rewards: the distant beacon hypothesis and the local cue hypothesis. In two field experiments, we found no evidence that rufous hummingbirds used a distant visual beacon to guide them to a rewarded location. In no case did birds abandon their approach to the goal location from a distance; rather they demonstrated remarkable accuracy of navigation by approaching to within about 70 cm of a rewarded flower's original location. Proximity varied depending on the size of the training flower: birds flew closer to a previously rewarded location if it had been previously signalled with a small beacon. Additionally, when provided with a beacon at a new location, birds did not fly directly to the new beacon. Taken together, we believe these data demonstrate that these hummingbirds depend little on visual characteristics to beacon to rewarded locations, but rather that they encode surrounding landmarks in order to reach the goal and then use the visual features of the goal as confirmation that they have arrived at the correct location.

  17. Determination of molecular parameters by electron collisions and laser techniques

    International Nuclear Information System (INIS)

    Colon, C.

    1989-01-01

    In this work a general procedure to study diatomic molecules in intermediate coupling scheme has been developed. This study allows to obtain expressions to calculate molecular line strengths and rotational transition intensities. These results are used in a numerical program to synthetize vibrational and rotational band spectra of any diatomic molecule. With this technique the experimental spectra of the first negative system of N 2 + and the fist positive system of N 2 are reproduced theoretically and it is possible to deduce its electronic transition moments values by comparison. Also the method has been applied to compare the synthetized bands with the experimental spectra of the B O u + -- x 1 Σ g + system of Au 2 and the A 2 Σ--- x 2 π system of OH. From these comparison band intensities and electronic moments can be deduced. The branching ratio method to measure the relative spectral response in the 1100-1560 A o =wavelength range of a vacuum uv monochromator has been used. Relative intensity of rotational lines with origine in a common upper vibrational-rotational level of Warner and Lyman systems of H 2 , have been measured. Also in this work, the deexcitation of the B 3 π + (0 + u ), v'=14 level of I 2 after pulsed laser excitation has been studied. The quenching cross sections by collisions with I 2 , H 2 , CO 2 and CH 4 have been determin-ed. (Author)

  18. Analysis of Downs syndrome with molecular techniques for future diagnoses

    Directory of Open Access Journals (Sweden)

    May Salem Al-Nbaheen

    2018-03-01

    Full Text Available Down syndrome (DS is a genetic disorder appeared due to the presence of trisomy in chromosome 21 in the G-group of the acrocentric region. DS is also known as non-Mendelian inheritance, due to the lack of Mendel’s laws. The disorder in children is identified through clinical symptoms and chromosomal analysis and till now there are no biochemical and molecular analyses. Presently, whole exome sequencing (WES has largely contributed in identifying the new disease-causing genes and represented a significant breakthrough in the field of human genetics and this technique uses high throughput sequencing technologies to determine the arrangement of DNA base pairs specifying the protein coding regions of an individual’s genome. Apart from this next generation sequencing and whole genome sequencing also contribute for identifying the disease marker. From this review, the suggestion was to perform the WES is DS children to identify the marker region. Keywords: Downs syndrome, Exome sequencing, Chromosomal analysis, Genes, Genetics

  19. Pedestrian hybrid beacon guide : recommendations and case study.

    Science.gov (United States)

    2014-01-01

    A pedestrian hybrid beacon (PHB) is a traffic control : device similar to a European pedestrian signal : (PELICAN) that was imported to the US and adapted by : engineers in Arizona to increase motorists awareness of : pedestrian crossings at uncon...

  20. A heuristic evaluation of the Facebook's advertising tool beacon

    OpenAIRE

    Jamal, A; Cole, M

    2009-01-01

    Interface usability is critical to the successful adoption of information systems. The aim of this study is to evaluate interface of Facebook's advertising tool Beacon by using privacy heuristics [4]. Beacon represents an interesting case study because of the negative media and user backlash it received. The findings of heuristic evaluation suggest violation of privacy heuristics [4]. Here, analysis identified concerns about user choice and consent, integrity and security of data, and awarene...

  1. Separation techniques for high-molecular-mass proteins.

    Science.gov (United States)

    Oh-Ishi, Masamichi; Maeda, Tadakazu

    2002-05-05

    Many high-molecular-mass (HMM) proteins (MW>100 kDa) are known to be involved in cytoskeleton, defence and immunity, transcription and translation in higher eukaryotic organisms. Even in the post-genomic era, purification of HMM protein is the first important step to analyze protein composition in a tissue or a cell (proteomics), to determine protein tertiary structure (structural biology), and to investigate protein function (functional genomics). To separate a HMM protein from a protein mixture, ions, chaotropes (urea and thiourea), detergents and protease inhibitors in extraction media and buffer solutions either for liquid chromatography or for gel electrophoresis should be carefully chosen, since HMM proteins tend to be aggregates under denatured condition and their long polypeptide chains are easily attacked by intrinsic proteases during separation procedure. Among many liquid chromatography techniques, affinity chromatography either with sequence-specific DNA for transcription factor, or with monoclonal antibody specific for myosin heavy chain has been used for preparative isolation of the respective HMM proteins. Though SDS-PAGE could analyze the size and the quantity of megadalton proteins, the resolution of HMM proteins is relatively poor. A newly developed pulse SDS-PAGE would be able to raise the resolution of HMM proteins compared with the conventional SDS-PAGE. The 2-DE method is not particularly suitable in analyzing HMM proteins larger than 200 kDa. However, a 2-DE method that uses an agarose IEF gel in the first dimension (agarose 2-DE) has been shown to produce significant improvements in 2-DE separation of HMM proteins larger than 150 kDa and up to 500 kDa.

  2. Molecular Genetics Techniques to Develop New Treatments for Brain Cancers

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Jacob; Fathallan-Shaykh, Hassan

    2006-09-22

    The objectives of this report are: (1) to devise novel molecular gene therapies for malignant brain tumors, (2) advance our understanding of the immune system in the central nervous system; and (3) apply genomics to find molecular probes to diagnose brain tumors, predict prognosis, biological behavior and their response to treatment.

  3. Molecular techniques: An overview of methods for the detection of ...

    African Journals Online (AJOL)

    Several DNA molecular markers are now available for use in surveillance and investigation of food-borne outbreaks that were previously difficult to detect. The results from several sources of literature indicate substantially different degrees of sensitivities between conventional detection methods and molecular-based ...

  4. Assessment of Knowledge of Participants on Basic Molecular Biology Techniques after 5-Day Intensive Molecular Biology Training Workshops in Nigeria

    Science.gov (United States)

    Yisau, J. I.; Adagbada, A. O.; Bamidele, T.; Fowora, M.; Brai, B. I. C.; Adebesin, O.; Bamidele, M.; Fesobi, T.; Nwaokorie, F. O.; Ajayi, A.; Smith, S. I.

    2017-01-01

    The deployment of molecular biology techniques for diagnosis and research in Nigeria is faced with a number of challenges, including the cost of equipment and reagents coupled with the dearth of personnel skilled in the procedures and handling of equipment. Short molecular biology training workshops were conducted at the Nigerian Institute of…

  5. Molecular Dynamics: from basic techniques to applications (A Molecular Dynamics Primer)

    Science.gov (United States)

    Hernández, E. R.

    2008-11-01

    It is now 50 years since the first papers describing the use of Molecular Dynamics (MD) were published by Alder and Wainright, and since then, together with Monte Carlo (MC) techniques, MD has become an essential tool in the theoretical study of materials properties at finite temperatures. In its early days, MD was used in combination with simple yet general models, such as hard spheres or Lennard-Jones models of liquids, systems which, though simple, were nevertheless not amenable to an analytical statistical mechanical treatment. Nowadays, however, MD is most frequently used in combination with rather sophisticated models, ranging all the way between empirical force fields to first-principles methods, with the aim of describing as accurately as possible any given material. From a computational aid in statistical mechanics and many-body physics, MD has evolved to become a widely used tool in physical chemistry, condensed matter physics, biology, geology and materials science. The aim of this course is to describe the basic algorithms of MD, and to provide attendees with the necessary theoretical background in order to enable them to use MD simulations in their research work. Also, examples of the use of MD in different scientific disciplines will be provided, with the aim of illustrating the the many possibilities and the wide spread use of MD simulation techniques in scientific research today.

  6. Practical Fingerprinting Localization for Indoor Positioning System by Using Beacons

    Directory of Open Access Journals (Sweden)

    Santosh Subedi

    2017-01-01

    Full Text Available Recent developments in the fields of smartphones and wireless communication technologies such as beacons, Wi-Fi, and ultra-wideband have made it possible to realize indoor positioning system (IPS with a few meters of accuracy. In this paper, an improvement over traditional fingerprinting localization is proposed by combining it with weighted centroid localization (WCL. The proposed localization method reduces the total number of fingerprint reference points over the localization space, thus minimizing both the time required for reading radio frequency signals and the number of reference points needed during the fingerprinting learning process, which eventually makes the process less time-consuming. The proposed positioning has two major steps of operation. In the first step, we have realized fingerprinting that utilizes lightly populated reference points (RPs and WCL individually. Using the location estimated at the first step, WCL is run again for the final location estimation. The proposed localization technique reduces the number of required fingerprint RPs by more than 40% compared to normal fingerprinting localization method with a similar localization estimation error.

  7. Element selective detection of molecular species applying chromatographic techniques and diode laser atomic absorption spectrometry.

    Science.gov (United States)

    Kunze, K; Zybin, A; Koch, J; Franzke, J; Miclea, M; Niemax, K

    2004-12-01

    Tunable diode laser atomic absorption spectroscopy (DLAAS) combined with separation techniques and atomization in plasmas and flames is presented as a powerful method for analysis of molecular species. The analytical figures of merit of the technique are demonstrated by the measurement of Cr(VI) and Mn compounds, as well as molecular species including halogen atoms, hydrogen, carbon and sulfur.

  8. Multiple systems for spatial learning: dead reckoning and beacon homing in rats.

    Science.gov (United States)

    Shettleworth, Sara J; Sutton, Jennifer E

    2005-04-01

    Rats homed with food in a large lighted arena. Without visual cues, they used dead reckoning. When a beacon indicated the home, rats could also use the beacon. Homing did not differ in 2 groups of rats, 1 provided with the beacon and 1 without it; tests without the beacon gave no evidence that beacon learning overshadowed dead reckoning (Experiment 1). When the beacon was at the home for 1 group and in random locations for another, there was again no evidence of cue competition (Experiment 2). Dead reckoning experience did not block acquisition of beacon homing (Experiment 3). Beacon learning and dead reckoning do not compete for predictive value but acquire information in parallel and are used hierarchically.

  9. Using current molecular techniques for rapid differentiation of ...

    African Journals Online (AJOL)

    Typhoid fever is responsible for the deaths of many people annually. However, conventional and timeconsuming detection methods for Salmonella Typhi still dominate. By using a molecular based approach, it was possible to identify Salmonella Typhi by amplifying two specific genes (viaB and tyv) and by using RFLP ...

  10. Molecular biology techniques for loss of heterozygosity detection: the glioma example

    Directory of Open Access Journals (Sweden)

    Tiago D. P. Ramos

    2015-06-01

    Full Text Available ABSTRACT In recent years, many oncology institutions have implemented the use of molecular approaches to assess and manage cancer patients. One commonly observed type of genetic alteration in cancer is the loss of heterozygosity (LOH. In the clinical setting, this molecular genetic marker is an important tool for disease prognosis, diagnosis and treatment. For example, the loss of 1p/19q is a classical molecular marker for oligodendroglioma assessment. In addition, this marker is associated with a favorable prognosis and chemosensitivity in oligodendroglial tumors. Interpretation of the clinical significance of molecular markers requires that health professionals and biomedical scientists understand the basic theoretical fundamentals of molecular diagnostic techniques. Although there are different methodologies to assess LOH, including high-performance techniques, this review aims to describe the polymerase chain reaction (PCR-based LOH assays and fluorescence in situ hybridization (FISH, which are the molecular techniques most used for evaluation of 1p/19q status in pathology laboratories.

  11. Beacon communities' public health initiatives: a case study analysis.

    Science.gov (United States)

    Massoudi, Barbara L; Marcial, Laura H; Haque, Saira; Bailey, Robert; Chester, Kelley; Cunningham, Shellery; Riley, Amanda; Soper, Paula

    2014-01-01

    The Beacon Communities for Public Health (BCPH) project was launched in 2011 to gain a better understanding of the range of activities currently being conducted in population- and public health by the Beacon Communities. The project highlighted the successes and challenges of these efforts with the aim of sharing this information broadly among the public health community. The Beacon Community Program, designed to showcase technology-enabled, community-based initiatives to improve outcomes, focused on: building and strengthening health information technology (IT) infrastructure and exchange capabilities; translating investments in health IT to measureable improvements in cost, quality, and population health; and, developing innovative approaches to performance measurement, technology, and care delivery. Four multimethod case studies were conducted based on a modified sociotechnical framework to learn more about public health initiative implementation and use in the Beacon Communities. Our methodological approach included using document review and semistructured key informant interviews. NACCHO Model Practice Program criteria were used to select the public health initiatives included in the case studies. Despite differences among the case studies, common barriers and facilitators were found to be present in all areas of the sociotechnical framework application including structure, people, technology, tasks, overarching considerations, and sustainability. Overall, there were many more facilitators (range = 7-14) present for each Beacon compared to barriers (range = 4-6). Four influential promising practices were identified through the work: forging strong and sustainable partnerships; ensuring a good task-technology fit and a flexible and iterative design; fostering technology acceptance; and, providing education and demonstrating value. A common weakness was the lack of a framework or model for the Beacon Communities evaluation work. Sharing a framework or approach

  12. BEACON: automated tool for Bacterial GEnome Annotation ComparisON.

    Science.gov (United States)

    Kalkatawi, Manal; Alam, Intikhab; Bajic, Vladimir B

    2015-08-18

    Genome annotation is one way of summarizing the existing knowledge about genomic characteristics of an organism. There has been an increased interest during the last several decades in computer-based structural and functional genome annotation. Many methods for this purpose have been developed for eukaryotes and prokaryotes. Our study focuses on comparison of functional annotations of prokaryotic genomes. To the best of our knowledge there is no fully automated system for detailed comparison of functional genome annotations generated by different annotation methods (AMs). The presence of many AMs and development of new ones introduce needs to: a/ compare different annotations for a single genome, and b/ generate annotation by combining individual ones. To address these issues we developed an Automated Tool for Bacterial GEnome Annotation ComparisON (BEACON) that benefits both AM developers and annotation analysers. BEACON provides detailed comparison of gene function annotations of prokaryotic genomes obtained by different AMs and generates extended annotations through combination of individual ones. For the illustration of BEACON's utility, we provide a comparison analysis of multiple different annotations generated for four genomes and show on these examples that the extended annotation can increase the number of genes annotated by putative functions up to 27%, while the number of genes without any function assignment is reduced. We developed BEACON, a fast tool for an automated and a systematic comparison of different annotations of single genomes. The extended annotation assigns putative functions to many genes with unknown functions. BEACON is available under GNU General Public License version 3.0 and is accessible at: http://www.cbrc.kaust.edu.sa/BEACON/ .

  13. Determining the stereochemical structures of molecular ions by ''Coulomb-explosion'' techniques with fast (MeV) molecular ion beams

    International Nuclear Information System (INIS)

    Gemmell, D.S.

    1980-01-01

    Recent studies on the dissociation of fast (MeV) molecular ion beams in thin foils suggest a novel alternative approach to the determination of molecular ion structures. In this article we review some recent high-resolution studies on the interactions of fast molecular ion beams with solid and gaseous targets and indicate how such studies may be applied to the problem of determining molecular ion structures. The main features of the Coulomb explosion of fast-moving molecular ion projectiles and the manner in which Coulomb-explosion techniques may be applied to the problem (difficult to attack by more conventional means) of determining the stereochemical structures of molecular ions has been described in this paper. Examples have been given of early experiments designed to elicit structure information. The techniques are still in their infancy, and it is to be expected that as both the technology and the analysis are refined, the method will make valuable contributions to the determination of molecular ion structures

  14. Assessment of knowledge of participants on basic molecular biology techniques after 5-day intensive molecular biology training workshops in Nigeria.

    Science.gov (United States)

    Yisau, J I; Adagbada, A O; Bamidele, T; Fowora, M; Brai, B I C; Adebesin, O; Bamidele, M; Fesobi, T; Nwaokorie, F O; Ajayi, A; Smith, S I

    2017-07-08

    The deployment of molecular biology techniques for diagnosis and research in Nigeria is faced with a number of challenges, including the cost of equipment and reagents coupled with the dearth of personnel skilled in the procedures and handling of equipment. Short molecular biology training workshops were conducted at the Nigerian Institute of Medical Research (NIMR), to improve the knowledge and skills of laboratory personnel and academics in health, research, and educational facilities. Five-day molecular biology workshops were conducted annually between 2011 and 2014, with participants drawn from health, research facilities, and the academia. The courses consisted of theoretical and practical sessions. The impact of the workshops on knowledge and skill acquisition was evaluated by pre- and post-tests which consisted of 25 multiple choice and other questions. Sixty-five participants took part in the workshops. The mean knowledge of molecular biology as evaluated by the pre- and post-test assessments were 8.4 (95% CI 7.6-9.1) and 13.0 (95 CI 11.9-14.1), respectively. The mean post-test score was significantly greater than the mean pre-test score (p biology workshop significantly increased the knowledge and skills of participants in molecular biology techniques. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(4):313-317, 2017. © 2017 The International Union of Biochemistry and Molecular Biology.

  15. Molecular characterization of water buffalo meat by proteomic techniques

    Directory of Open Access Journals (Sweden)

    L. Chianese

    2010-02-01

    Full Text Available Buffalo breeding in Campania is aimed at milk production as the starting material for the production of Mozzarella di Bufala DOP, but it does not take into account the possibility of meat production. Buffalo meat, given its low content in fat and cholesterol, represents a good alternative to bovine meat from the dietetic standpoint. One of most interesting aspects of buffalo meat is its utilization either directly or to prepare other products. Development of these products however requires suitable technological approaches based on molecular characterization, so that product evaluation and development may be carried out on rational basis.

  16. Molecular imaging with optics: primer and case for near-infrared fluorescence techniques in personalized medicine

    Science.gov (United States)

    Sevick-Muraca, Eva M.; Rasmussen, John C.

    2010-01-01

    We compare and contrast the development of optical molecular imaging techniques with nuclear medicine with a didactic emphasis for initiating readers into the field of molecular imaging. The nuclear imaging techniques of gamma scintigraphy, single-photon emission computed tomography, and positron emission tomography are first briefly reviewed. The molecular optical imaging techniques of bioluminescence and fluorescence using gene reporter/probes and gene reporters are described prior to introducing the governing factors of autofluorescence and excitation light leakage. The use of dual-labeled, near-infrared excitable and radio-labeled agents are described with comparative measurements between planar fluorescence and nuclear molecular imaging. The concept of time-independent and -dependent measurements is described with emphasis on integrating time-dependent measurements made in the frequency domain for 3-D tomography. Finally, we comment on the challenges and progress for translating near-infrared (NIR) molecular imaging agents for personalized medicine. PMID:19021311

  17. Laboratory techniques in plant molecular biology taught with UniformMu insertion alleles of maize

    Science.gov (United States)

    An undergraduate course - Laboratory Techniques in Plant Molecular Biology - was organized around our research application of UniformMu insertion alleles to investigate mitochondrial functions in plant reproduction. The course objectives were to develop students’ laboratory, record keeping, bioinfor...

  18. Early Detection of Breast Cancer Using Molecular Beacons

    Science.gov (United States)

    2008-01-01

    DCIS tissues (Figure 6). Therefore, in addition to three tumor markers that were originally proposed for this study, we added HIF-1α and uPAR as...Ambrosini, G., Adida , C., and Altieri, D. C. (1997) Nat. Med. 3, 917–921 17. Tanaka, K., Iwamoto, S., Gon, G., Nohara, T., Iwamoto,M., andTanigawa, N...lab will only be given the ID number of each sample. All research results will be recorded using the ID numbers. The original experimental records

  19. Early Detection of Breast Cancer Using Molecular Beacons

    National Research Council Canada - National Science Library

    Yang, Lily

    2004-01-01

    .... We also developed a procedure to detect both survivin and cyclin Dl gene expression simultaneously in single cancer cells, which increases the sensitivity and specificity of detection of cancer cells...

  20. Studies of molecular dynamics with neutron scattering techniques. Part of a coordinated programme on neutron scattering techniques

    International Nuclear Information System (INIS)

    Vinhas, L.A.

    1980-05-01

    Molecular dynamics was studied in samples of tert-butanol, cyclohexanol and methanol, using neutron inelastic and quasi-elastic techniques. The frequency spectra of cyclohexanol in crystalline phase were interpreted by assigning individual energy peaks to hindered rotation of molecules, lattice vibration, hydrogen bond stretching and ring bending modes. Neutron quasi-elastic scattering measurements permitted the testing of models for molecular diffusion as a function of temperature. The interpretation of neutron incoherent inelastic scattering on methanol indicated the different modes of molecular dynamics in this material; individual inelastic peaks in the spectra could be assigned to vibrations of crystalline lattice, stretching of hydrogen bond and vibrational and torsional modes of CH 3 OH molecule. The results of the experimental work on tertbutanol indicate two distinct modes of motion in this material: individual molecular librations are superposed to a cooperative rotation diffusion which occurs both in solid and in liquid state

  1. Application of molecular techniques in the study of Staphylococcus aureus clonal evolution - A Review

    Directory of Open Access Journals (Sweden)

    Adriana Marcos Vivoni

    2005-11-01

    Full Text Available Staphylococcus aureus is an important agent of healthcare-associated and community-acquired infections. A major characteristic of this microorganism is the ability to develop resistance to antimicrobial agents. Several molecular techniques have been applied for the characterization of S. aureus in epidemiological studies. In the present review, we discuss the application of molecular techniques for typing S. aureus strains and describe the nomenclature and evolution of epidemic clones of this important pathogen.

  2. Using "Pseudomonas Putida xylE" Gene to Teach Molecular Cloning Techniques for Undergraduates

    Science.gov (United States)

    Dong, Xu; Xin, Yi; Ye, Li; Ma, Yufang

    2009-01-01

    We have developed and implemented a serial experiment in molecular cloning laboratory course for undergraduate students majored in biotechnology. "Pseudomonas putida xylE" gene, encoding catechol 2, 3-dioxygenase, was manipulated to learn molecular biology techniques. The integration of cloning, expression, and enzyme assay gave students…

  3. Diagnosis of active tuberculosis disease: From microscopy to molecular techniques

    Directory of Open Access Journals (Sweden)

    Adam J. Caulfield

    2016-08-01

    Full Text Available Methods used for the laboratory diagnosis of tuberculosis are continually evolving in order to achieve more rapid, less expensive, and accurate results. Acid-fast staining and culture for mycobacteria remain at the core of any diagnostic algorithm. Following growth in culture, molecular technologies such as nucleic acid hybridization probes, MALDI-TOF MS, and DNA sequencing may be used for definitive species identification. Nucleic acid amplification methods allow for the direct detection of Mycobacterium tuberculosis complex within respiratory specimens without relying on culture growth, leading to more rapid diagnoses and appropriate patient care. Keywords: Acid-fast staining, Sputum processing, Tuberculosis culture, MALDI-TOF, Sequencing, GeneXpert MTB/RIF assay

  4. Polymicrobial chronic endophthalmitis diagnosed by culture and molecular technique.

    Science.gov (United States)

    Mukherjee, A; Pramanik, S; Das, D; Roy, R; Therese, K L

    2014-01-01

    Accurate etiological diagnosis is the key to prevention of ocular morbidity in endophthalmitis cases. A 66 year old male was suffering from chronic endophthalmitis post-cataract surgery. Polymerase chain reaction examination on anterior chamber fluid was positive for Propionibacterium acnes but negative for the panfungal genome. He was advised vitrectomy with intravitreal injections. Polymerase chain reaction of vitreous aspirate was positive for P.acnes as well as panfungal genome. The vitreous sample also grew yeast in culture which was identified as Candida pseudotropicalis. Patient was treated on an alternate day regimen of intravitreal Vancomycin and Amphotericin B in the post-operative period. There was improvement in vision at final follow up. Chronic endophthalmitis can have polymicrobial etiology which will require appropriate diagnostic and therapeutic strategies. The role of molecular testing is vital in these cases as growth in culture is often negative.

  5. [Etiologic diagnosis in meningitis and encephalitis molecular biology techniques].

    Science.gov (United States)

    Conca, Natalia; Santolaya, María Elena; Farfan, Mauricio J; Cofré, Fernanda; Vergara, Alejandra; Salazar, Liliana; Torres, Juan Pablo

    2016-01-01

    The aetiological study of infections of the central nervous system has traditionally been performed using bacterial cultures and, more recently, using polymerase chain reaction (PCR) for herpes simplex virus (HSV). Bacterial cultures may not have good performance, especially in the context of patients who have received antibiotics prior to sampling, and a request for HSV only by PCR reduces the information to only one aetiological agent. The aim of this study is to determine the infectious causes of meningitis and encephalitis, using traditional microbiology and molecular biology to improve the aetiological diagnosis of these diseases. A prospective study was conducted on 19 patients with suspected meningitis, admitted to the Luis Calvo Mackenna Hospital in Santiago, Chile, from March 1, 2011 to March 30, 2012. After obtaining informed consent, the CSF samples underwent cytochemical study, conventional culture, multiplex PCR for the major producing bacterial meningitis (N. meningitidis, S. pneumoniae, H. influenzae), real-time single PCR for HSV-1 and 2, VZV, EBV, CMV, HHV-6 and enterovirus. Clinical and epidemiological data were also collected from the clinical records. Of the 19 patients analysed, 2 were diagnosed by conventional methods and 7 by adding molecular biology (increase to 37%). Three patients had meningitis due to S. pneumoniae, one due to Enterobacter cloacae, 2 patients meningoencephalitis HSV-1, and one VZV meningitis. The addition of PCR to conventional diagnostic methods in CNS infections increases the probability of finding the causal agent. This allows a more adequate, timely and rational management of the disease. Copyright © 2014. Publicado por Elsevier España, S.L.U.

  6. On the Efficiency of Secure Beaconing in VANETs

    NARCIS (Netherlands)

    Schoch, Elmar; Kargl, Frank

    Direct inter-vehicle communication enables numerous safety applications like intersection collision warning. Beacons - periodic one-hop link-layer broadcast messages containing, e.g., location, heading, and speed - are the basis for many such applications. For security, current work often requires

  7. Tumor functional and molecular imaging utilizing ultrasound and ultrasound-mediated optical techniques.

    Science.gov (United States)

    Yuan, Baohong; Rychak, Joshua

    2013-02-01

    Tumor functional and molecular imaging has significantly contributed to cancer preclinical research and clinical applications. Among typical imaging modalities, ultrasonic and optical techniques are two commonly used methods; both share several common features such as cost efficiency, absence of ionizing radiation, relatively inexpensive contrast agents, and comparable maximum-imaging depth. Ultrasonic and optical techniques are also complementary in imaging resolution, molecular sensitivity, and imaging space (vascular and extravascular). The marriage between ultrasonic and optical techniques takes advantages of both techniques. This review introduces tumor functional and molecular imaging using microbubble-based ultrasound and ultrasound-mediated optical imaging techniques. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  8. The BEACON on-line core monitoring system. Functional upgrades and applications

    International Nuclear Information System (INIS)

    Boyd, W.A.; Miller, R.W.

    1997-01-01

    The BEACON TM core monitor system has been in commercial operation since 1989 and was licensed by the USNRC for on-line core power distribution and thermal power limit monitoring in 1994. Since that time BEACON has been installed at 17 plants. Each of these customers has a different perspective on the use of data from BEACON and a different approach on the application of BEACON to support their plant operations. To support these varied needs and approaches the BEACON system has been divided into three operational levels to better match the system functions to the customer needs and approaches to system integration. Based on customer feedback, the BEACON system was upgraded in some areas and streamlined in other areas to better support the needs of each customer. The three operational levels of the BEACON system, the major product upgrades and system evolution that has taken place to support the needs and applications of our customers are discussed. (authors)

  9. Smartphone-Based Indoor Localization with Bluetooth Low Energy Beacons.

    Science.gov (United States)

    Zhuang, Yuan; Yang, Jun; Li, You; Qi, Longning; El-Sheimy, Naser

    2016-04-26

    Indoor wireless localization using Bluetooth Low Energy (BLE) beacons has attracted considerable attention after the release of the BLE protocol. In this paper, we propose an algorithm that uses the combination of channel-separate polynomial regression model (PRM), channel-separate fingerprinting (FP), outlier detection and extended Kalman filtering (EKF) for smartphone-based indoor localization with BLE beacons. The proposed algorithm uses FP and PRM to estimate the target's location and the distances between the target and BLE beacons respectively. We compare the performance of distance estimation that uses separate PRM for three advertisement channels (i.e., the separate strategy) with that use an aggregate PRM generated through the combination of information from all channels (i.e., the aggregate strategy). The performance of FP-based location estimation results of the separate strategy and the aggregate strategy are also compared. It was found that the separate strategy can provide higher accuracy; thus, it is preferred to adopt PRM and FP for each BLE advertisement channel separately. Furthermore, to enhance the robustness of the algorithm, a two-level outlier detection mechanism is designed. Distance and location estimates obtained from PRM and FP are passed to the first outlier detection to generate improved distance estimates for the EKF. After the EKF process, the second outlier detection algorithm based on statistical testing is further performed to remove the outliers. The proposed algorithm was evaluated by various field experiments. Results show that the proposed algorithm achieved the accuracy of <2.56 m at 90% of the time with dense deployment of BLE beacons (1 beacon per 9 m), which performs 35.82% better than <3.99 m from the Propagation Model (PM) + EKF algorithm and 15.77% more accurate than <3.04 m from the FP + EKF algorithm. With sparse deployment (1 beacon per 18 m), the proposed algorithm achieves the accuracies of <3.88 m at 90% of the

  10. Smartphone-Based Indoor Localization with Bluetooth Low Energy Beacons

    Directory of Open Access Journals (Sweden)

    Yuan Zhuang

    2016-04-01

    Full Text Available Indoor wireless localization using Bluetooth Low Energy (BLE beacons has attracted considerable attention after the release of the BLE protocol. In this paper, we propose an algorithm that uses the combination of channel-separate polynomial regression model (PRM, channel-separate fingerprinting (FP, outlier detection and extended Kalman filtering (EKF for smartphone-based indoor localization with BLE beacons. The proposed algorithm uses FP and PRM to estimate the target’s location and the distances between the target and BLE beacons respectively. We compare the performance of distance estimation that uses separate PRM for three advertisement channels (i.e., the separate strategy with that use an aggregate PRM generated through the combination of information from all channels (i.e., the aggregate strategy. The performance of FP-based location estimation results of the separate strategy and the aggregate strategy are also compared. It was found that the separate strategy can provide higher accuracy; thus, it is preferred to adopt PRM and FP for each BLE advertisement channel separately. Furthermore, to enhance the robustness of the algorithm, a two-level outlier detection mechanism is designed. Distance and location estimates obtained from PRM and FP are passed to the first outlier detection to generate improved distance estimates for the EKF. After the EKF process, the second outlier detection algorithm based on statistical testing is further performed to remove the outliers. The proposed algorithm was evaluated by various field experiments. Results show that the proposed algorithm achieved the accuracy of <2.56 m at 90% of the time with dense deployment of BLE beacons (1 beacon per 9 m, which performs 35.82% better than <3.99 m from the Propagation Model (PM + EKF algorithm and 15.77% more accurate than <3.04 m from the FP + EKF algorithm. With sparse deployment (1 beacon per 18 m, the proposed algorithm achieves the accuracies of <3.88 m at

  11. Techniques for studying protein trafficking and molecular motors in neurons.

    Science.gov (United States)

    Feng, Shanxi; Arnold, Don B

    2016-09-01

    This review focused on techniques that facilitated the visualization of protein trafficking. In the mid-1990s the cloning of GFP allowed fluorescently tagged proteins to be expressed in cells and then visualized in real time. This advance allowed a glimpse, for the first time, of the complex system within cells for distributing proteins. It quickly became apparent, however, that time-lapse sequences of exogenously expressed GFP-labeled proteins can be difficult to interpret. Reasons for this include the relatively low signal that comes from moving proteins and high background rates from stationary proteins and other sources, as well as the difficulty of identifying the origins and destinations of specific vesicular carriers. In this review a range of techniques that have overcome these issues to varying degrees was reviewed and the insights into protein trafficking that they have enabled were discussed. Concentration will be on neurons, as they are highly polarized and, thus, their trafficking systems tend to be accessible for study. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Detecting Molecular Properties by Various Laser-Based Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hsin, Tse-Ming [Iowa State Univ., Ames, IA (United States)

    2007-01-01

    Four different laser-based techniques were applied to study physical and chemical characteristics of biomolecules and dye molecules. These techniques are liole burning spectroscopy, single molecule spectroscopy, time-resolved coherent anti-Stokes Raman spectroscopy and laser-induced fluorescence microscopy. Results from hole burning and single molecule spectroscopy suggested that two antenna states (C708 & C714) of photosystem I from cyanobacterium Synechocystis PCC 6803 are connected by effective energy transfer and the corresponding energy transfer time is ~6 ps. In addition, results from hole burning spectroscopy indicated that the chlorophyll dimer of the C714 state has a large distribution of the dimer geometry. Direct observation of vibrational peaks and evolution of coumarin 153 in the electronic excited state was demonstrated by using the fs/ps CARS, a variation of time-resolved coherent anti-Stokes Raman spectroscopy. In three different solvents, methanol, acetonitrile, and butanol, a vibration peak related to the stretch of the carbonyl group exhibits different relaxation dynamics. Laser-induced fluorescence microscopy, along with the biomimetic containers-liposomes, allows the measurement of the enzymatic activity of individual alkaline phosphatase from bovine intestinal mucosa without potential interferences from glass surfaces. The result showed a wide distribution of the enzyme reactivity. Protein structural variation is one of the major reasons that are responsible for this highly heterogeneous behavior.

  13. BEACON: automated tool for Bacterial GEnome Annotation ComparisON

    KAUST Repository

    Kalkatawi, Manal M.

    2015-08-18

    Background Genome annotation is one way of summarizing the existing knowledge about genomic characteristics of an organism. There has been an increased interest during the last several decades in computer-based structural and functional genome annotation. Many methods for this purpose have been developed for eukaryotes and prokaryotes. Our study focuses on comparison of functional annotations of prokaryotic genomes. To the best of our knowledge there is no fully automated system for detailed comparison of functional genome annotations generated by different annotation methods (AMs). Results The presence of many AMs and development of new ones introduce needs to: a/ compare different annotations for a single genome, and b/ generate annotation by combining individual ones. To address these issues we developed an Automated Tool for Bacterial GEnome Annotation ComparisON (BEACON) that benefits both AM developers and annotation analysers. BEACON provides detailed comparison of gene function annotations of prokaryotic genomes obtained by different AMs and generates extended annotations through combination of individual ones. For the illustration of BEACON’s utility, we provide a comparison analysis of multiple different annotations generated for four genomes and show on these examples that the extended annotation can increase the number of genes annotated by putative functions up to 27 %, while the number of genes without any function assignment is reduced. Conclusions We developed BEACON, a fast tool for an automated and a systematic comparison of different annotations of single genomes. The extended annotation assigns putative functions to many genes with unknown functions. BEACON is available under GNU General Public License version 3.0 and is accessible at: http://www.cbrc.kaust.edu.sa/BEACON/

  14. A comparison of the techniques for the study of molecular motion in crystals

    International Nuclear Information System (INIS)

    Powles, J.G.

    1976-01-01

    An informal review is presented of the nature of molecular motion in molecular crystals. Particular attention is paid to the various methods of experimental measurement, especially with regard to the actual information about molecular motion which can be obtained and to the 'selectivity' of the different techniques. The latter include: self-diffusion by tracer and nuclear spin relaxation in a field gradient; dielectric and infra-red absorption; slow-neutron sacttering; Rayleigh and Raman scattering; nuclear magnetic spin relaxation; and computer simulation techniques. (orig.) [de

  15. Detection of multidrug resistance using molecular nuclear technique

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Tae; Ahn, Byeong Cheol [School of Medicine, Kyungpook National Univ., Daegu (Korea, Republic of)

    2004-04-01

    Although the outcome of cancer patients after cytotoxic chemotherapy is related diverse mechanisms, multidrug resistance (MDR) for chemotherapeutic drugs due to cellular P-glycoprotein (Pgp) or multidrug-resistance associated protein (MRP) is most important factor in the chemotherapy failure to cancer. A large number of pharmacologic compounds, including verapamil, quinidine, tamoxifen, cyclosporin A and quinolone derivatives have been reported to overcome MDR. Single photon emission computed tomography (SPECT) and positron emission tomography (PET) are available for the detection of Pgp and MRP-mediated transporter. {sup 99}m-Tc-MIBI and other {sup 99}m-Tc-radiopharmaceuticals are substrates for Pgp and MRP, and have been used in clinical studies for tumor imaging, and to visualize blockade of Pgp-mediated transport after modulation of Pgp pump. Colchicine, verapamil and daunorubicin labeled with {sup 11}C have been evaluated for the quantification of Pgp-mediated transport with PET in vivo and reported to be feasible substrates with which to image Pgp function in tumors. Leukotrienes are specific substrates for MRP and N-({sup 11}C)acetyl-leukotriene E4 provides an opportunity to study MRP function non-invasively in vivo. SPECT and PET pharmaceuticals have successfully used to evaluate pharmacologic effects of MDR modulators. Imaging of MDR and reversal of MDR with bioluminescence in a living animal is also evaluated for future clinical trial. We have described recent advances in molecular imaging of MDR and reviewed recent publications regarding feasibility of SPECT and PET imaging to study the functionality of MDR transporters in vivo.

  16. Status of biotechnology with emphasis on molecular techniques for mutation breeding in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Lapade, A.G.; Nazarea, T.Y.; Veluz, A.M.S.; Marbella, L.J.; Nato, A.Q.; Coloma, C.B. Jr.; Asencion, A.B. [Philippine Nuclear Research Institute, Commonwealth Avenue, Quezon (Philippines)

    2002-02-01

    This paper summarizes the status of biotechnology with emphasis on molecular techniques for plant breeding in the Philippines. Several molecular and in-vitro culture techniques are integrated in plant breeding for crop improvement at PNRI, UPLB, IRRI and PhilRice. At IRRI, PCR techniques, RFLP and RAPD, PCR techniques, RFLP and RAPD were developed to establish high density molecular maps, determine breadth and diversity of germplasm and characterize alien introgression. The molecular maps have identified DNA sequence of resistance genes of HYVs and NPTs to abiotic and biotic stresses, the major achievement is the development of high density molecular maps in rice with at least 2000 markers. The biotechnology program at PhilRice for varietal improvement includes: (1) utilization of molecular marker technology such gene mapping of desired traits in rice, analysis of genetic relationships of germplasm materials and breeding lines through DNA fingerprinting and genetic diversity studies and development and application of marker aided selection for disease resistance (RTD and BLB); (2) application of in-vitro techniques in the development of lines with tolerance to adverse conditions; (3) molecular cloning of important genes for RTD resistance; (4) genetic transformation for male sterility and resistance to sheath blight and stem borers; and (5) transfer of disease resistance from wild species to cultivated varieties. In IPB, molecular markers:microsatellites or SSR, AFLP and RGA are being used for mapping and diversity studies in coconut, mango, banana, mungbean, corn and tomato. Mutation breeding at PNRI using gamma radiation has resulted in the development of crop varieties with desirable traits. The use of AFLP coupled to PCR is being used to study polymorphism in plant variants of radiation-induced mutants of rice, pineapple and ornamentals. (author)

  17. Molecular detection of drug resistance in microbes by isotopic techniques: The IAEA experience

    International Nuclear Information System (INIS)

    Dar, L.; Boussaha, A.; Padhy, A.K.; Khan, B.

    2003-01-01

    The International Atomic Energy Agency (IAEA) supports various programmes on the uses of radionuclide techniques in the management of human communicable diseases. An important issue, being addressed through several technology transfer projects, is the detection of drug resistance in microbes by radioisotope based molecular-biology diagnostic procedures. The techniques employed include dot blot hybridisation with P-32 labelled oligonucleotide probes to detect point mutations, associated with drug resistance, in microbial genes amplified by the polymerase chain reaction (PCR). Molecular methods have been used for the detection of drug resistance in the malarial parasite, Plasmodium falciparum, and in Mycobacterium tuberculosis. Radioisotope based molecular-biology methods have been demonstrated to have comparative advantages in being sensitive, specific, cost-effective, and suitable for application to large-scale molecular surveillance for drug resistance. (author)

  18. Molecular Detection of Antimicrobial Resistance

    Science.gov (United States)

    Fluit, Ad C.; Visser, Maarten R.; Schmitz, Franz-Josef

    2001-01-01

    The determination of antimicrobial susceptibility of a clinical isolate, especially with increasing resistance, is often crucial for the optimal antimicrobial therapy of infected patients. Nucleic acid-based assays for the detection of resistance may offer advantages over phenotypic assays. Examples are the detection of the methicillin resistance-encoding mecA gene in staphylococci, rifampin resistance in Mycobacterium tuberculosis, and the spread of resistance determinants across the globe. However, molecular assays for the detection of resistance have a number of limitations. New resistance mechanisms may be missed, and in some cases the number of different genes makes generating an assay too costly to compete with phenotypic assays. In addition, proper quality control for molecular assays poses a problem for many laboratories, and this results in questionable results at best. The development of new molecular techniques, e.g., PCR using molecular beacons and DNA chips, expands the possibilities for monitoring resistance. Although molecular techniques for the detection of antimicrobial resistance clearly are winning a place in routine diagnostics, phenotypic assays are still the method of choice for most resistance determinations. In this review, we describe the applications of molecular techniques for the detection of antimicrobial resistance and the current state of the art. PMID:11585788

  19. A Partnership Training Program in Breast Cancer Research Using Molecular Imaging Techniques

    Science.gov (United States)

    2008-07-01

    behavior of calcium, stimulates bone formation and has been used in the treatment of post menopausal osteoporosis . There have been several reports on anti...using molecular imaging techniques. 2. Offer molecular imaging and breast cancer- related lectures, seminars, workshops, and laboratory internships. 3...bioluminescence assay system was related to the number of viable cells over a wide range (102 to 105 cells per well). The decrease in luminescence was

  20. A Partnership Training Program in Breast Cancer Research Using Molecular Imaging Techniques

    Science.gov (United States)

    2007-07-01

    tiny calcium deposits that 82 indicate changes within the breast possibly point- 83 ing to cancer . Microcalcifications especially are 84 usually...NUMBER A Partnership Training Program in Breast Cancer Research Using Molecular Imaging Techniques 5b. GRANT NUMBER W81XWH-05-1-0291 5c. PROGRAM...assistant were further trained in molecular imaging of breast cancer through seminars and workshops, and are currently conducting two research projects

  1. The role and future of in-vitro isotopic techniques in molecular biology

    International Nuclear Information System (INIS)

    Dar, L.; Khan, B.K.

    2004-01-01

    In this review we discuss isotopic in-vitro molecular biology techniques, and their advantages and applications. Isotopic methods have helped to shape molecular biology since its early days. Despite the availability of non-isotopic alternatives, isotopic methods continue to be used in molecular biology due to certain advantages, especially related to sensitivity and cost-effectiveness. Numerous techniques involving the use of isotopes help in the characterization of genes, including the detection of single nucleotide polymorphisms (SNPs) or mutations. Other isotopic molecular methods are utilized to study the phenotypic expression of gene sequences and their mutation. Emerging branches of molecular biology like functional genomics and proteomics are extremely important for exploiting the rapidly growing data derived from whole genomic sequencing of human and microbial genomes. Recent molecular biology applications like the high-throughput array techniques are relevant in the context of both structural and functional genomics. In proteomics, stable isotope based technology has found applications in the analysis of protein structure and interactions. (author)

  2. Performance of MAC protocols in beaconing Mobile Adhoc Multibroadcast Networks

    OpenAIRE

    Rico García, Cristina; Lehner, Andreas; Robertson, Patrick; Strang, Thomas

    2010-01-01

    The investigation of infrastructureless safety applications in dierent transportation systems is a hot research topic. The nodes in thevnetwork are designed to advertise to the rest of the nodes informationabout the current traffic situation by means of short beacon messages containing speed, direction, positions and other relevant safety information. The scheduling should be organized by the MAC layer so that the transmitted messages arrive successfully as soon as possible at the recei...

  3. Nanomechanical DNA origami 'single-molecule beacons' directly imaged by atomic force microscopy

    Science.gov (United States)

    Kuzuya, Akinori; Sakai, Yusuke; Yamazaki, Takahiro; Xu, Yan; Komiyama, Makoto

    2011-01-01

    DNA origami involves the folding of long single-stranded DNA into designed structures with the aid of short staple strands; such structures may enable the development of useful nanomechanical DNA devices. Here we develop versatile sensing systems for a variety of chemical and biological targets at molecular resolution. We have designed functional nanomechanical DNA origami devices that can be used as 'single-molecule beacons', and function as pinching devices. Using 'DNA origami pliers' and 'DNA origami forceps', which consist of two levers ~170 nm long connected at a fulcrum, various single-molecule inorganic and organic targets ranging from metal ions to proteins can be visually detected using atomic force microscopy by a shape transition of the origami devices. Any detection mechanism suitable for the target of interest, pinching, zipping or unzipping, can be chosen and used orthogonally with differently shaped origami devices in the same mixture using a single platform. PMID:21863016

  4. Contemporary nucleic acid-based molecular techniques for detection, identification, and characterization of Bifidobacterium.

    Science.gov (United States)

    Mianzhi, Yao; Shah, Nagendra P

    2017-03-24

    Bifidobacteria are one of the most important bacterial groups found in the gastrointestinal tract of humans. Medical and food industry researchers have focused on bifidobacteria because of their health-promoting properties. Researchers have historically relied on classic phenotypic approaches (culture and biochemical tests) for detection and identification of bifidobacteria. Those approaches still have values for the identification and detection of some bifidobacterial species, but they are often labor-intensive and time-consuming and can be problematic in differentiating closely related species. Rapid, accurate, and reliable methods for detection, identification, and characterization of bifidobacteria in a mixed bacterial population have become a major challenge. The advent of nucleic acid-based molecular techniques has significantly advanced isolation and detection of bifidobacteria. Diverse nucleic acid-based molecular techniques have been employed, including hybridization, target amplification, and fingerprinting. Certain techniques enable the detection, characterization, and identification at genus-, species-, and strains-levels, whereas others allow typing of species or strains of bifidobacteria. In this review, an overview of methodological principle, technique complexity, and application of various nucleic acid-based molecular techniques for detection, identification, and characterization of bifidobacteria is presented. Advantages and limitations of each technique are discussed, and significant findings based on particular techniques are also highlighted.

  5. Studies of Phase Transformation in Molecular Crystals Using the Positron Annihilation Technique

    DEFF Research Database (Denmark)

    Eldrup, Morten Mostgaard; Lightbody, David; Sherwood, John N.

    1980-01-01

    An examination has been made of the brittle/plastic phase transformation in the molecular crystals cyclohexane, DL-camphene and succinonitrile using the positron annihilation technique. In each material, the transition is characterized by a distinct increase in ortho-positronium lifetime. The inf......An examination has been made of the brittle/plastic phase transformation in the molecular crystals cyclohexane, DL-camphene and succinonitrile using the positron annihilation technique. In each material, the transition is characterized by a distinct increase in ortho-positronium lifetime...

  6. Adapting Mobile Beacon-Assisted Localization in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Wei Dong

    2009-04-01

    Full Text Available The ability to automatically locate sensor nodes is essential in many Wireless Sensor Network (WSN applications. To reduce the number of beacons, many mobile-assisted approaches have been proposed. Current mobile-assisted approaches for localization require special hardware or belong to centralized localization algorithms involving some deterministic approaches due to the fact that they explicitly consider the impreciseness of location estimates. In this paper, we first propose a range-free, distributed and probabilistic Mobile Beacon-assisted Localization (MBL approach for static WSNs. Then, we propose another approach based on MBL, called Adapting MBL (A-MBL, to increase the efficiency and accuracy of MBL by adapting the size of sample sets and the parameter of the dynamic model during the estimation process. Evaluation results show that the accuracy of MBL and A-MBL outperform both Mobile and Static sensor network Localization (MSL and Arrival and Departure Overlap (ADO when both of them use only a single mobile beacon for localization in static WSNs.

  7. Adapting mobile beacon-assisted localization in wireless sensor networks.

    Science.gov (United States)

    Teng, Guodong; Zheng, Kougen; Dong, Wei

    2009-01-01

    The ability to automatically locate sensor nodes is essential in many Wireless Sensor Network (WSN) applications. To reduce the number of beacons, many mobile-assisted approaches have been proposed. Current mobile-assisted approaches for localization require special hardware or belong to centralized localization algorithms involving some deterministic approaches due to the fact that they explicitly consider the impreciseness of location estimates. In this paper, we first propose a range-free, distributed and probabilistic Mobile Beacon-assisted Localization (MBL) approach for static WSNs. Then, we propose another approach based on MBL, called Adapting MBL (A-MBL), to increase the efficiency and accuracy of MBL by adapting the size of sample sets and the parameter of the dynamic model during the estimation process. Evaluation results show that the accuracy of MBL and A-MBL outperform both Mobile and Static sensor network Localization (MSL) and Arrival and Departure Overlap (ADO) when both of them use only a single mobile beacon for localization in static WSNs.

  8. Current status of molecular biological techniques for plant breeding in the Republic of Korea

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Seong-Han; Lee, Si-Myung; Park, Bum-Seok; Yun, In-Sun; Goo, Doe-Hoe; Kim, Seok-Dong [Rural Development Administration, National Institute of Agricultural Science and Technology, Suwon (Korea)

    2002-02-01

    Classical plant breeding has played an important role in developing new varieties in current agriculture. For decades, the technique of cross-pollination has been popular for breeding in cereal and horticultural crops to introduce special traits. However, recently the molecular techniques get widely accepted as an alternative tool in both introducing a useful trait for developing the new cultivars and investigating the characteristics of a trait in plant, like the identification of a gene. Using the advanced molecular technique, several genetically modified (GM) crops (e.g., Roundup Ready Soybean, YieldGard, LibertyLink etc.) became commercially cultivated and appeared in the global market since 1996. The GM crops, commercially available at the moment, could be regarded as successful achievements in history of crop breeding conferring the specific gene into economically valuable crops to make them better. Along with such achievements, on the other hand these new crops have also caused the controversial debate on the safety of GM crops as human consumption and environmental release as well. Nevertheless, molecular techniques are widespread and popular in both investigating the basic science of plant biology and breeding new varieties compared to their conventional counterparts. Thus, the Department of Bioresources at the National Institute of Agricultural Science and Technology (NIAST) has been using the molecular biological techniques as a complimentary tool for the improvement of crop varieties for almost two decades. (author)

  9. An Analysis of the Optimal Placement of Beacon in Bluetooth-INS Indoor Localization

    OpenAIRE

    Zhao, Xinyu; Ruan, Ling; Zhang, Ling; Long, Yi; Cheng, Fei

    2018-01-01

    The placement of Bluetooth beacon has immediate impact on the accuracy and stability of indoor positioning. Affected by the shelter of building and human, Bluetooth shows uncertain spatial transmission characteristics. Therefore, the scientific deployment of the beacon nodes is closely related to the indoor space environment. In the study of positioning technology using Bluetooth, some scholars have discussed the deployment of Bluetooth beacon in different scenarios. In the principle of avoid...

  10. Comparison of classical and molecular techniques for the determination of microbial biodiversity in Mediterranean crop soils

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, A.; Lopez-Pineiro, A.; Ramirez, M.

    2009-07-01

    Soil microbe ecology has lately become increasingly important in the study of soil microbe populations. direct extraction of soil bacteria DNA allows PCR and DGGE analyses for the microorganism identification of these complex samples, avoiding the need for time-consuming culture-dependent techniques. The aim of the present study was to compare the two techniques (culture-dependent and molecular culture-independent) in four different plots of maize (Zea mays L.) crop under irrigation in south-western Spain. (Author)

  11. Application of nonlinear optical techniques for the investigation of molecular properties and collisional processes

    International Nuclear Information System (INIS)

    Bischel, W.K.

    1975-09-01

    Molecular collisional processes were studied by using two different nonlinear optical techniques utilizing CO 2 lasers. The first study used the techniques of saturation spectroscopy to study the momentum transfer in one direction which occurs when CO 2 collides with itself, H 2 , Ne, NH 3 , and CH 3 F. Average CO 2 velocity changes determined from these experiments were typically 1 / 10 the thermal velocity or less. A theoretical model was also developed to explain the experimental observations of CO 2 with foreign gas perturbers. Generally good agreement between this model and the data was obtained. The second technique utilized the high-resolution capabilities of Doppler-free two-photon absorption (DFTPA) for the study of molecular properties and collisional processes in the two molecules CH 3 F and NH 3 . The first observation of DFTPA in molecular systems using two fixed-frequency CO 2 optical fields in combination with molecular Stark tuning is reported. The pressure broadening coefficient and the pressure shift of the O → ν 3 transition were measured; broadening coefficients for the foreign gas perturbers of He and CF 3 I were determined. A self-broadening coefficient of the O → 2ν 2 transition was also measured; foreign gas broadening coefficients for the collision partners H 2 , D 2 , He, Ne, and Xe were determined. Spectroscopic information was also obtained about these two molecular systems. (62 figures, 33 tables, 182 references) (U.S.)

  12. Use of molecular biology techniques in the detection of fraud meat in ...

    African Journals Online (AJOL)

    Microsoft

    2015-02-04

    Feb 4, 2015 ... Use of molecular biology techniques in the detection of fraud meat in the Egyptian market ... Nowadays consumers are increasingly aware of their health and are looking for more comprehensive information on the safety of the foods they consume. (Verbeke and Ward, 2006). In spite of the food labeling.

  13. Molecular techniques for the identification and detection of microorganisms relevant for the food industry

    NARCIS (Netherlands)

    Klijn, N.

    1996-01-01

    The research described in this thesis concerns the development and application in food microbiology of molecular identification and detection techniques based on 16S rRNA sequences. The technologies developed were applied to study the microbial ecology of two groups of bacteria, namely

  14. Molecular tagging techniques and their applications to the study of complex thermal flow phenomena

    Science.gov (United States)

    Chen, Fang; Li, Haixing; Hu, Hui

    2015-08-01

    This review article reports the recent progress in the development of a new group of molecule-based flow diagnostic techniques, which include molecular tagging velocimetry (MTV) and molecular tagging thermometry (MTT), for both qualitative flow visualization of thermally induced flow structures and quantitative whole-field measurements of flow velocity and temperature distributions. The MTV and MTT techniques can also be easily combined to result in a so-called molecular tagging velocimetry and thermometry (MTV&T) technique, which is capble of achieving simultaneous measurements of flow velocity and temperature distribution in fluid flows. Instead of using tiny particles, the molecular tagging techniques (MTV, MTT, and MTV&T) use phosphorescent molecules, which can be turned into long-lasting glowing marks upon excitation by photons of appropriate wavelength, as the tracers for the flow velocity and temperature measurements. The unique attraction and implementation of the molecular tagging techniques are demonstrated by three application examples, which include: (1) to quantify the unsteady heat transfer process from a heated cylinder to the surrounding fluid flow in order to examine the thermal effects on the wake instabilities behind the heated cylinder operating in mixed and forced heat convection regimes, (2) to reveal the time evolution of unsteady heat transfer and phase changing process inside micro-sized, icing water droplets in order to elucidate the underlying physics pertinent to aircraft icing phenomena, and (3) to achieve simultaneous droplet size, velocity and temperature measurements of "in-flight" droplets to characterize the dynamic and thermodynamic behaviors of flying droplets in spray flows.

  15. Weak beacon detection for air-to-ground optical wireless link establishment.

    Science.gov (United States)

    Han, Yaoqiang; Dang, Anhong; Tang, Junxiong; Guo, Hong

    2010-02-01

    In an air-to-ground free-space optical communication system, strong background interference seriously affects the beacon detection, which makes it difficult to establish the optical link. In this paper, we propose a correlation beacon detection scheme under strong background interference conditions. As opposed to traditional beacon detection schemes, the beacon is modulated by an m-sequence at the transmitting terminal with a digital differential matched filter (DDMF) array introduced at the receiving end to detect the modulated beacon. This scheme is capable of suppressing both strong interference and noise by correlation reception of the received image sequence. In addition, the DDMF array enables each pixel of the image sensor to have its own DDMF of the same structure to process its received image sequence in parallel, thus it makes fast beacon detection possible. Theoretical analysis and an outdoor experiment have been demonstrated and show that the proposed scheme can realize fast and effective beacon detection under strong background interference conditions. Consequently, the required beacon transmission power can also be reduced dramatically.

  16. Beacon- and Schema-Based Method for Recognizing Algorithms from Students' Source Code

    Science.gov (United States)

    Taherkhani, Ahmad; Malmi, Lauri

    2013-01-01

    In this paper, we present a method for recognizing algorithms from students programming submissions coded in Java. The method is based on the concept of "programming schemas" and "beacons". Schemas are high-level programming knowledge with detailed knowledge abstracted out, and beacons are statements that imply specific…

  17. Crowdsourcing for Context: Regarding Privacy in Beacon Encounters via Contextual Integrity

    Directory of Open Access Journals (Sweden)

    Bello-Ogunu Emmanuel

    2016-07-01

    Full Text Available Research shows that context is important to the privacy perceptions associated with technology. With Bluetooth Low Energy beacons, one of the latest technologies for providing proximity and indoor tracking, the current identifiers that characterize a beacon are not sufficient for ordinary users to make informed privacy decisions about the location information that could be shared. One solution would be to have standardized category and privacy labels, produced by beacon providers or an independent third-party. An alternative solution is to find an approach driven by users, for users. In this paper, we propose a novel crowdsourcing based approach to introduce elements of context in beacon encounters.We demonstrate the effectiveness of this approach through a user study, where participants use a crowd-based mobile app designed to collect beacon category and privacy information as a scavenger hunt game. Results show that our approach was effective in helping users label beacons according to the specific context of a given beacon encounter, as well as the privacy perceptions associated with it. This labeling was done with an accuracy of 92%, and with an acceptance rate of 82% of all recommended crowd labels. Lastly, we conclusively show how crowdsourcing for context can be used towards a user-centric framework for privacy management during beacon encounters.

  18. Determination of BEACON Coupling Coefficients using data from Xenon transient

    International Nuclear Information System (INIS)

    Bozic, M.; Kurincic, B.

    2007-01-01

    NEK uses BEACO TM code (BEACO TM - Westinghouse Best Estimate Analyzer for Core Operating Nuclear) for core monitoring, analysis and core behaviour prediction. Coupling Coefficients determine relationship between core response and excore instrumentation. Measured power distribution using incore moveable detectors during Xenon transient with sufficient power axial offset change is the most important data for further analysis. Classic methodology and BEACO TM Conservative methodology using established Coupling Coefficients are compared on NPP Krsko case. BEACON TM Conservative methodology with predefined Coupling Coefficients is used as a surveillance tool for verification of relationship between core and excore instrumentation during power operation. (author)

  19. The tick (Acari: Ixodidae) fauna of Herald's Beacon Islet, Australia.

    Science.gov (United States)

    Kwak, Mackenzie L; Mintram, Kate

    2017-01-01

    A rare opportunity to travel to Herald's Beacon Islet with permission from the Australian government to collect ticks allowed for a survey of the tick fauna of the island to be undertaken for the first time. The avian fauna of the island, which serve as hosts, was also recorded and includes one new species record for the island. The seabird soft tick Ornithodoros capensis Neumann and the seabird hard tick Amblyomma loculosum Neumann were found to be present on the island. Images of the ticks present on the island are presented along with morphological characters for their identification.

  20. Australian endemic pest tephritids: genetic, molecular and microbial tools for improved Sterile Insect Technique

    OpenAIRE

    Raphael, Kathryn A; Shearman, Deborah CA; Gilchrist, A Stuart; Sved, John A; Morrow, Jennifer L; Sherwin, William B; Riegler, Markus; Frommer, Marianne

    2014-01-01

    Among Australian endemic tephritid fruit flies, the sibling species Bactrocera tryoni and Bactrocera neohumeralis have been serious horticultural pests since the introduction of horticulture in the nineteenth century. More recently, Bactrocera jarvisi has also been declared a pest in northern Australia. After several decades of genetic research there is now a range of classical and molecular genetic tools that can be used to develop improved Sterile Insect Technique (SIT) strains for control ...

  1. Phosphate-solubilizing bacteria as inoculants for agriculture: use of updated molecular techniques in their study

    OpenAIRE

    Igual , José; Valverde , Angel; Cervantes , Emilio; Velázquez , Encarna

    2001-01-01

    International audience; The use of phosphate-solubilizing bacteria (PSB) as inoculants simultaneously increases P uptake by the plant and crop yield. A method to isolate efficient strains, an overview of some updated molecular techniques useful in their characterization (16S rRNA sequencing, LMW RNA profiles, TP-RADP and rep-PCR fingerprinting) and a method for obtaining strain-specific DNA probes will be briefly explained. These methodologies are not time-consuming and, in general, do not re...

  2. [Molecular classification of breast cancer patients obtained through the technique of chromogenic in situ hybridization (CISH)].

    Science.gov (United States)

    Fernández, Angel; Reigosa, Aldo

    2013-12-01

    Breast cancer is a heterogeneous disease composed of a growing number of biological subtypes, with substantial variability of the disease progression within each category. The aim of this research was to classify the samples object of study according to the molecular classes of breast cancer: luminal A, luminal B, HER2 and triple negative, as a result of the state of HER2 amplification obtained by the technique of chromogenic in situ hybridization (CISH). The sample consisted of 200 biopsies fixed in 10% formalin, processed by standard techniques up to paraffin embedding, corresponding to patients diagnosed with invasive ductal carcinoma of the breast. These biopsies were obtained from patients from private practice and the Institute of Oncology "Dr. Miguel Pérez Carreño", for immunohistochemistry (IHC) of hormone receptors and HER2 made in the Hospital Metropolitano del Norte, Valencia, Venezuela. The molecular classification of the patient's tumors considering the expression of estrogen and progesterone receptors by IHC and HER2 amplification by CISH, allowed those cases originally classified as unknown, since they had an indeterminate (2+) outcome for HER2 expression by IHC, to be grouped into the different molecular classes. Also, this classification permitted that some cases, initially considered as belonging to a molecular class, were assigned to another class, after the revaluation of the HER2 status by CISH.

  3. Bio-functions and molecular carbohydrate structure association study in forage with different source origins revealed using non-destructive vibrational molecular spectroscopy techniques.

    Science.gov (United States)

    Ji, Cuiying; Zhang, Xuewei; Yan, Xiaogang; Mostafizar Rahman, M; Prates, Luciana L; Yu, Peiqiang

    2017-08-05

    The objectives of this study were to: 1) investigate forage carbohydrate molecular structure profiles; 2) bio-functions in terms of CHO rumen degradation characteristics and hourly effective degradation ratio of N to OM (HED N/OM ), and 3) quantify interactive association between molecular structures, bio-functions and nutrient availability. The vibrational molecular spectroscopy was applied to investigate the structure feature on a molecular basis. Two sourced-origin alfalfa forages were used as modeled forages. The results showed that the carbohydrate molecular structure profiles were highly linked to the bio-functions in terms of rumen degradation characteristics and hourly effective degradation ratio. The molecular spectroscopic technique can be used to detect forage carbohydrate structure features on a molecular basis and can be used to study interactive association between forage molecular structure and bio-functions. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Bio-functions and molecular carbohydrate structure association study in forage with different source origins revealed using non-destructive vibrational molecular spectroscopy techniques

    Science.gov (United States)

    Ji, Cuiying; Zhang, Xuewei; Yan, Xiaogang; Mostafizar Rahman, M.; Prates, Luciana L.; Yu, Peiqiang

    2017-08-01

    The objectives of this study were to: 1) investigate forage carbohydrate molecular structure profiles; 2) bio-functions in terms of CHO rumen degradation characteristics and hourly effective degradation ratio of N to OM (HEDN/OM), and 3) quantify interactive association between molecular structures, bio-functions and nutrient availability. The vibrational molecular spectroscopy was applied to investigate the structure feature on a molecular basis. Two sourced-origin alfalfa forages were used as modeled forages. The results showed that the carbohydrate molecular structure profiles were highly linked to the bio-functions in terms of rumen degradation characteristics and hourly effective degradation ratio. The molecular spectroscopic technique can be used to detect forage carbohydrate structure features on a molecular basis and can be used to study interactive association between forage molecular structure and bio-functions.

  5. Design and implementation of Bluetooth beacon in mobile payment system

    Science.gov (United States)

    Han, Tiantian; Ding, Lei

    2017-08-01

    The current line of payment means, mainly in the following ways, cash payment, credit card payment, WeChat Alipay sweep payment. There are many inconvenience in Cash payment, large amounts of cash inconvenience to carry, count the money to spend time and effort, true and false banknotes difficult to distinguish, ticket settlement easy to go wrong. Credit card payment is relatively time-consuming, and WeChat Alipay sweep payment need to sweep. Therefore, the design of a convenient, fast payment to meet the line to pay the demand is particularly important. Based on the characteristics of BLE Bluetooth wireless communication technology, this paper designs a kind of payment method based on Bluetooth beacon. Through the Bluetooth beacon broadcast consumption, consumers only need to open the relevant APP in the Android client, and you can get Bluetooth via mobile phone Bluetooth the amount of consumption of the standard broadcast, in accordance with the corresponding payment platform to complete the payment process, which pay less time to improve the efficiency of payment.

  6. Experience of molecular monitoring techniques in upstream oil and gas operations

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Anthony F.; Anfindsen, Hilde; Liengen, Turid; Molid, Solfrid [Statoil ASA (Denmark)

    2011-07-01

    For a numbers of years, molecular monitoring tools have been used in upstream oil and gas operations but the results have given only limited added value. This paper discusses the various techniques available for upstream molecular monitoring which provides scope for identification of microbial influenced problems. The methodology, which consists of analyzing solid samples using traditional as well as molecular techniques, is detailed. Two cases were studied with the objective of determining if microbial contamination was contributing to the problem. The first case was a study of amorphous deposits in production wells and mainly iron sulphide was found. The second study was of amorphous deposits in water injection wells and the analysis showed typical components of drilling and completion fluids with some organic material. Two more cases, corrosion of tubing in a water injection well and flow line corrosion, are discussed and the results are given. From the study, it can be concluded that failure can be due to several factors, chemical and biological.

  7. Use of molecular marker techniques in seed testing by Brazilian seed companies

    Directory of Open Access Journals (Sweden)

    Della Vecchia P.T.

    1998-01-01

    Full Text Available Seed market is becoming global and globalization is growing very fast. To compete favourably in this new global seed world, quality and cost are and will be certanly the key issues. High seed quality can only be obtained by a thorough control of the entire seed production process, step by step from planning to final delivery. That requires science, technology, expertise, experience, good management and certanly, the most important, an absolute and unconditional commitment with quality. Seed testing for quality assurance is one important step in the process of production of high quality seed. In the late years a considerable amount of research has been published, particularly on the use of some Polymerase Chain Reaction DNA based new technologies (RAPD, microsatelites, AFLP for genetic purity determinations in seed testing. As far as we know, no Brazilian seed company is using, on regular basis, RAPD or other molecular marker techniques in the determination of genetic purity in seed testing. Most of these are using morphological or physiological traits expressed by seed, seedling or mature plant and/or electrophoresis of seed or seedling proteins/isoenzymes for that purpose. Main reasons for that are: DNA molecular marker techniques are relatively new; lack of specialized personnel to run DNA molecular marker assays on routine basis; higher cost/sample when compared to proteins/isoenzymes electrophoresis.

  8. Theory of the double-edge molecular technique for Doppler lidar wind measurement.

    Science.gov (United States)

    Flesia, C; Korb, C L

    1999-01-20

    The theory of the double-edge lidar technique for measuring the wind with molecular backscatter is described. Two high-spectral-resolution edge filters are located in the wings of the Rayleigh-Brillouin profile. This doubles the signal change per unit Doppler shift, the sensitivity, and improves measurement accuracy relative to the single-edge technique by nearly a factor of 2. The use of a crossover region where the sensitivity of a molecular- and an aerosol-based measurement is equal is described. Use of this region desensitizes the molecular measurement to the effects of aerosol scattering over a velocity range of +/-100 m/s. We give methods for correcting short-term, shot-to-shot, frequency jitter and drift with a laser reference frequency measurement and methods for long-term frequency correction with a servo control system. The effects of Rayleigh-Brillouin scattering on the measurement are shown to be significant and are included in the analysis. Simulations for a conical scanning satellite-based lidar at 355 nm show an accuracy of 2-3 m/s for altitudes of 2-15 km for a 1-km vertical resolution, a satellite altitude of 400 km, and a 200 km x 200 km spatial resolution.

  9. Theory of the Double-Edge Molecular Technique for Doppler Lidar Wind Measurement

    Science.gov (United States)

    Flesia, Cristina; Korb, C. Laurence

    1999-01-01

    The theory of the double-edge lidar technique for measuring the wind with molecular backscatter is described. Two high-spectral-resolution edge filters are located in the wings of the Rayleigh Brillouin profile. This doubles the signal change per unit Doppler shift, the sensitivity, and improves measurement accuracy relative to the single-edge technique by nearly a factor of 2. The use of a crossover region where the sensitivity of a molecular- and an aerosol-based measurement is equal is described. Use of this region desensitizes the molecular measurement to the effects of aerosol scattering over a velocity range of 100 m s. We give methods for correcting short-term, shot-to-shot, frequency jitter and drift with a laser reference frequency measurement and methods for long-term frequency correction with a servo control system. The effects of Rayleigh Brillouin scattering on the measurement are shown to be significant and are included in the analysis. Simulations for a conical scanning satellite-based lidar at 355 nm show an accuracy of 2 3 m s for altitudes of 2 15 km for a 1-km vertical resolution, a satellite altitude of 400 km, and a 200 km 200 km spatial resolution.

  10. Pedestrian and motorists' actions at pedestrian hybrid beacon sites: findings from a pilot study.

    Science.gov (United States)

    Pulugurtha, Srinivas S; Self, Debbie R

    2015-01-01

    This paper focuses on an analysis of pedestrian and motorists' actions at sites with pedestrian hybrid beacons and assesses their effectiveness in improving the safety of pedestrians. Descriptive and statistical analyses (one-tail two-sample T-test and two-proportion Z-test) were conducted using field data collected during morning and evening peak hours at three study sites in the city of Charlotte, NC, before and after the installation of pedestrian hybrid beacons. Further, an analysis was conducted to assess the change in pedestrian and motorists' actions over time (before the installation; 1 month, 3 months, 6 months, and 12 months after the installation). Results showed an increase in average traffic speed at one of the pedestrian hybrid beacon sites while no specific trends were observed at the other two pedestrian hybrid beacon sites. A decrease in the number of motorists not yielding to pedestrians, pedestrians trapped in the middle of the street, and pedestrian-vehicle conflicts were observed at all the three pedestrian hybrid beacon sites. The installation of pedestrian hybrid beacons did not have a negative effect on pedestrian actions at two out of the three sites. Improvements seem to be relatively more consistent 3 months after the installation of the pedestrian hybrid beacon.

  11. Atmospheric Beacons of Life from Exoplanets Around G and K Stars

    Science.gov (United States)

    Airapetian, Vladimir S.; Jackman, Charles H.; Mlynczak, Martin; Danchi, William; Hunt, Linda

    2017-01-01

    The current explosion in detection and characterization of thousands of extrasolar planets from the Kepler mission, the Hubble Space Telescope, and large ground-based telescopes opens a new era in searches for Earth-analog exoplanets with conditions suitable for sustaining life. As more Earth-sized exoplanets are detected in the near future, we will soon have an opportunity to identify habitale worlds. Which atmospheric biosignature gases from habitable planets can be detected with our current capabilities? The detection of the common biosignatures from nitrogen-oxygen rich terrestrial-type exoplanets including molecular oxygen (O2), ozone (O3), water vapor (H2O), carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) requires days of integration time with largest space telescopes, and thus are very challenging for current instruments. In this paper we propose to use the powerful emission from rotational-vibrational bands of nitric oxide, hydroxyl and molecular oxygen as signatures of nitrogen, oxygen, and water rich atmospheres of terrestrial type exoplanets "highlighted" by the magnetic activity from young G and K main-sequence stars. The signals from these fundamental chemical prerequisites of life we call atmospheric "beacons of life" create a unique opportunity to perform direct imaging observations of Earth-sized exoplanets with high signal-to-noise and low spectral resolution with the upcoming NASA missions.

  12. Advanced molecular diagnostic techniques for detection of food-borne pathogens: Current applications and future challenges.

    Science.gov (United States)

    Umesha, S; Manukumar, H M

    2018-01-02

    The elimination of disease-causing microbes from the food supply is a primary goal and this review deals with the overall techniques available for detection of food-borne pathogens. Now-a-days conventional methods are replaced by advanced methods like Biosensors, Nucleic Acid-based Tests (NAT), and different PCR-based techniques used in molecular biology to identify specific pathogens. Bacillus cereus, Staphylococcus aureus, Proteus vulgaris, Escherichia coli, Campylobacter, Listeria monocytogenes, Salmonella spp., Aspergillus spp., Fusarium spp., Penicillium spp., and pathogens are detected in contaminated food items that cause always diseases in human in any one or the other way. Identification of food-borne pathogens in a short period of time is still a challenge to the scientific field in general and food technology in particular. The low level of food contamination by major pathogens requires specific sensitive detection platforms and the present area of hot research looking forward to new nanomolecular techniques for nanomaterials, make them suitable for the development of assays with high sensitivity, response time, and portability. With the sound of these, we attempt to highlight a comprehensive overview about food-borne pathogen detection by rapid, sensitive, accurate, and cost affordable in situ analytical methods from conventional methods to recent molecular approaches for advanced food and microbiology research.

  13. Nanotools and molecular techniques to rapidly identify and fight bacterial infections.

    Science.gov (United States)

    Dinarelli, S; Girasole, M; Kasas, S; Longo, G

    2017-07-01

    Reducing the emergence and spread of antibiotic-resistant bacteria is one of the major healthcare issues of our century. In addition to the increased mortality, infections caused by multi-resistant bacteria drastically enhance the healthcare costs, mainly because of the longer duration of illness and treatment. While in the last 20years, bacterial identification has been revolutionized by the introduction of new molecular techniques, the current phenotypic techniques to determine the susceptibilities of common Gram-positive and Gram-negative bacteria require at least two days from collection of clinical samples. Therefore, there is an urgent need for the development of new technologies to determine rapidly drug susceptibility in bacteria and to achieve faster diagnoses. These techniques would also lead to a better understanding of the mechanisms that lead to the insurgence of the resistance, greatly helping the quest for new antibacterial systems and drugs. In this review, we describe some of the tools most currently used in clinical and microbiological research to study bacteria and to address the challenge of infections. We discuss the most interesting advancements in the molecular susceptibility testing systems, with a particular focus on the many applications of the MALDI-TOF MS system. In the field of the phenotypic characterization protocols, we detail some of the most promising semi-automated commercial systems and we focus on some emerging developments in the field of nanomechanical sensors, which constitute a step towards the development of rapid and affordable point-of-care testing devices and techniques. While there is still no innovative technique that is capable of completely substituting for the conventional protocols and clinical practices, many exciting new experimental setups and tools could constitute the basis of the standard testing package of future microbiological tests. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Tight Bounds for Beacon-Based Coverage in Simple Rectilinear Polygons

    KAUST Repository

    Bae, Sang Won

    2016-03-21

    We establish tight bounds for beacon-based coverage problems. In particular, we show that $$\\\\lfloor \\\\frac{n}{6} \\ floor $$⌊n6⌋ beacons are always sufficient and sometimes necessary to cover a simple rectilinear polygon P with n vertices. When P is monotone and rectilinear, we prove that this bound becomes $$\\\\lfloor \\\\frac{n+4}{8} \\ floor $$⌊n+48⌋. We also present an optimal linear-time algorithm for computing the beacon kernel of P.

  15. Detecting and Preventing Beacon Replay Attacks in Receiver-Initiated MAC Protocols for Energy Efficient WSNs

    DEFF Research Database (Denmark)

    Di Mauro, Alessio; Fafoutis, Xenofon; Mödersheim, Sebastian Alexander

    2013-01-01

    nodes, pretending to have a fake identity within the network. To prevent this attack we propose RAP, a challenge-response authentication protocol that is able to detect and prevent the beacon replay attack. The effectiveness of the protocol is formally verified using OFMC and ProVerif. Furthermore, we......In receiver-initiated MAC protocols for Wireless Sensor Networks (WSNs), communication is initiated by the receiver of the data through beacons containing the receiver's identity. In this paper, we consider the case of a network intruder that captures and replays such beacons towards legitimate...

  16. Spectroscopic and molecular docking techniques study of the interaction between oxymetholone and human serum albumin

    Energy Technology Data Exchange (ETDEWEB)

    Madrakian, Tayyebeh, E-mail: madrakian@basu.ac.ir; Bagheri, Habibollah; Afkhami, Abbas; Soleimani, Mohammad

    2014-11-15

    In this study, the binding of oxymetholone (OXM), a doping drug, to human serum albumin (HSA) was explored at pH 7.40 by spectroscopic methods including spectrofluorimetry, three dimensional excitation–emission matrix (3D EEM), UV–vis absorption, resonance rayleigh scattering (RRS) and molecular docking. The fluorescence results showed that there was a considerable quenching of the intrinsic fluorescence of HSA upon binding to OXM by static quenching mechanism. The Stern–Volmer quenching constants (K{sub SV}) between OXM and HSA at three different temperatures 295, 303, 308 K, were obtained as 4.63×10{sup 4}, 3.05×10{sup 4} and 1.49×10{sup 4} L mol{sup −1}, respectively. Furthermore this interaction was confirmed by UV–vis spectrophotometric and RRS techniques. The binding site number, n, apparent binding constant, K{sub b}, and corresponding thermodynamic parameters (ΔS, ΔH and ΔG) were measured at different temperatures. The Van der Waals and hydrogen-bond forces were found to stabilize OXM–HSA complex. The distance (r) between the donor and acceptor was obtained from Förster's theory of fluorescence resonance energy transfer (FRET) and found to be 1.67 nm. The 3D EEM showed that OXM slightly changes the secondary structure of HSA. Furthermore, the molecular docking was employed for identification of drug binding sites and interaction of OXM with amino acid residues. - Highlights: • The binding of OXM as a doping drug with HSA was studied by different techniques. • The binding constant of HSA–OXM was calculated. • The binding site of OXM on HSA was characterized with molecular docking. • The thermodynamic parameters were calculated according to fluorescence technique.

  17. Applied Protein and Molecular Techniques for Characterization of B Cell Neoplasms in Horses

    Science.gov (United States)

    Badial, Peres R.; Tallmadge, Rebecca L.; Miller, Steven; Stokol, Tracy; Richards, Kristy; Borges, Alexandre S.

    2015-01-01

    Mature B cell neoplasms cover a spectrum of diseases involving lymphoid tissues (lymphoma) or blood (leukemia), with an overlap between these two presentations. Previous studies describing equine lymphoid neoplasias have not included analyses of clonality using molecular techniques. The objective of this study was to use molecular techniques to advance the classification of B cell lymphoproliferative diseases in five adult equine patients with a rare condition of monoclonal gammopathy, B cell leukemia, and concurrent lymphadenopathy (lymphoma/leukemia). The B cell neoplasms were phenotypically characterized by gene and cell surface molecule expression, secreted immunoglobulin (Ig) isotype concentrations, Ig heavy-chain variable (IGHV) region domain sequencing, and spectratyping. All five patients had hyperglobulinemia due to IgG1 or IgG4/7 monoclonal gammopathy. Peripheral blood leukocyte immunophenotyping revealed high proportions of IgG1- or IgG4/7-positive cells and relative T cell lymphopenia. Most leukemic cells lacked the surface B cell markers CD19 and CD21. IGHG1 or IGHG4/7 gene expression was consistent with surface protein expression, and secreted isotype and Ig spectratyping revealed one dominant monoclonal peak. The mRNA expression of the B cell-associated developmental genes EBF1, PAX5, and CD19 was high compared to that of the plasma cell-associated marker CD38. Sequence analysis of the IGHV domain of leukemic cells revealed mutated Igs. In conclusion, the protein and molecular techniques used in this study identified neoplastic cells compatible with a developmental transition between B cell and plasma cell stages, and they can be used for the classification of equine B cell lymphoproliferative disease. PMID:26311245

  18. Nanosecond and femtosecond mass spectroscopic analysis of a molecular beam produced by the spray-jet technique

    International Nuclear Information System (INIS)

    Yamada, Toshiki; Shinohara, Hidenori; Kamikado, Toshiya; Okuno, Yoshishige; Suzuki, Hitoshi; Mashiko, Shinro; Yokoyama, Shiyoshi

    2008-01-01

    The spray-jet molecular beam apparatus enabled us to produce a molecular beam of non-volatile molecules under high vacuum from a sprayed mist of sample solutions. The apparatus has been used in spectroscopic studies and as a means of molecular beam deposition. We analyzed the molecular beam, consisting of non-volatile, solvent, and carrier-gas molecules, by using femtosecond- and nanosecond- laser mass spectroscopy. The information thus obtained provided insight into the molecular beam produced by the spray-jet technique

  19. A comparison of reactor and linac techniques for neutron diffraction studies of molecular liquids

    International Nuclear Information System (INIS)

    Dore, J.C.; Clarke, J.H.

    1976-01-01

    A comparison is made of the experimental measurement of slow neutron diffraction from molecular liquids using a reactor (steady state) and a linac (pulsed) neutron source. Consideration is given to relative intensities, resolution and sample configuration for the two methods over a wide range of momentum transfer values. Possible errors in the liquid structure factor, Ssub(m)(Q), are examined in terms of established procedures for 'experimental' (absorption and multiple scattering) and 'analytic' (Placzek) corrections. The complementary nature of the two methods is emphasized and the implications for further development of the linac technique are examined. (Auth.)

  20. Seamless Guidance System Combining GPS, BLE Beacon, and NFC Technologies

    Directory of Open Access Journals (Sweden)

    Rung-Shiang Cheng

    2016-01-01

    Full Text Available Users rely increasingly on Location-Based Services (LBS and automated navigation/guidance systems nowadays. However, while such services are easily implemented in outdoor environments using Global Positioning System (GPS technology, a requirement still exists for accurate localization and guidance schemes in indoor settings. Accordingly, the present study proposes a system based on GPS, Bluetooth Low Energy (BLE beacons, and Near Field Communication (NFC technology. Through establishing graphic information and the design of algorithm, this study develops a guidance system for indoors and outdoors on smart phones, wishing to give user perfect smart life through this system. The proposed system is implemented on a smart phone and evaluated on a student campus environment. The experimental results confirm the ability of the proposed app to switch automatically from an outdoor mode to an indoor mode and to guide the user to requested target destination via the shortest possible route.

  1. Gender identification of Grasshopper Sparrows comparing behavioral, morphological, and molecular techniques

    Science.gov (United States)

    Ammer, F.K.; Wood, P.B.; McPherson, R.J.

    2008-01-01

    Correct gender identification in monomorphic species is often difficult especially if males and females do not display obvious behavioral and breeding differences. We compared gender specific morphology and behavior with recently developed DNA techniques for gender identification in the monomorphic Grasshopper Sparrow (Ammodramus savannarum). Gender was ascertained with DNA in 213 individuals using the 2550F/2718R primer set and 3% agarose gel electrophoresis. Field observations using behavior and breeding characteristics to identify gender matched DNA analyses with 100% accuracy for adult males and females. Gender was identified with DNA for all captured juveniles that did not display gender specific traits or behaviors in the field. The molecular techniques used offered a high level of accuracy and may be useful in studies of dispersal mechanisms and winter assemblage composition in monomorphic species.

  2. Application of Molecular Cytogenetic Technique for Rapid Prenatal Diagnosis of Aneuploidies in Iranian Population

    Directory of Open Access Journals (Sweden)

    Habib Nasiri

    2009-06-01

    Full Text Available Objective: Classic cell culture and karyotyping is routinely used for prenatal detection of different chromosomal abnormalities. Molecular cytogenetic techniques have also recently been developed and used for this purpose. Quantitative florescence PCR using short tandem repeat (STR markers has more potential for high throughput diagnosis. Marker heterozygosity in short tandem repeats (STR is of critical importance in the clinical applicablity of this method. Materials and Methods: Different STR markers on chromosomes 13, 18, 21, X and Y  were analysed from  amniotic samples to detect related disorders such as Down, Edward, Patau,  Klinefelter sundromes , as well as sex chromosomes numerical abnormalities . Results: In our population some markers (D18S976, DXS6854, D21S11, and D21S1411 showed alleles with sizes out of expected ranges. But others occupied narrower range of predicted distribution. Most markers have enough heterozygosity (66.3-94.7 to be used for prenatal diagnosis. Furthermore, results obtained from full karyotype for all samples were in concordance with results of molecular cytogenetic testing. Conclusion: It is concluded that, in urgent situations, if proper markers used, molecular cytogenetic testing (QF-PCR could be a useful method for rapid prenatal diagnosis (PND in populations with high rate of consanguinity such as Iran.  

  3. [Application of molecular epidemiology techniques in the study of food poisoning caused by Staphylococcus aureus].

    Science.gov (United States)

    Montserrat, I; March, F; de Simón, M; Llovet, T; Ferrer, M D; Coll, P; Prats, G

    1994-10-01

    The use of molecular epidemiology techniques has provided better knowledge as to the clonal organization of bacterian populations and thus allows better follow up of epidemics. An alimentary toxiinfection in a Barcelona school produced by Staphylococcus aureus was analyzed by the combination of epidemiologic, phenotype and genotype markers with the aim of determining the source of the alimentary contamination. Nine strains of Staphylococcus aureus isolated in 6 food manipulators and 3 patients were studied with the following markers: biotype, antibiotype, phagotype, plasmid profile, polymorphism of the size of the restriction fragments of total DNA and ribotype. Epidemiologic study of the strains analyzed showed that both the phenotype markers and the plasmid profile are thecniques of little discriminatory value. The only clearly discriminatory technique used was ribotyping which defined 3 clones in the 9 strains of Staphylococcus aureus studied. Molecular study of isolated strains of Staphylococcus aureus was able to identify the causal origin of the alimentary toxiinfection in one of the 6 food manipulators studied.

  4. Multi-kW Uplink Fiber-Laser Beacon with Agile Signal Format Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Uplink Laser Beacons for deep-space communication, can benefit greatly from migration to the 1010-1030nm wavelengths, via use of Silicon-APDs on the spacecraft...

  5. Multi-kW Uplink Fiber-Laser Beacon with Agile Signal Format Project

    Data.gov (United States)

    National Aeronautics and Space Administration —  Laser beacons with scalable powers are needed for ground to deep-space optical communication uplinks. They serve as absolute reference for tracking of...

  6. Evaluation of light-emitting diode beacon light fixtures : final report.

    Science.gov (United States)

    2009-12-01

    Rotating beacons containing filament light sources have long been used on highway maintenance trucks : to indicate the presence of the truck to other drivers. Because of advances in light-emitting diode (LED) : technologies, flashing lights containin...

  7. Optimal placement of range-only beacons for mobile robot localisation

    CSIR Research Space (South Africa)

    Burke, Michael G

    2011-11-01

    Full Text Available -only Beacons for Mobile Robot Localisation Michael Burke Mobile Intelligent Autonomous Systems Council for Scientific and Industrial Research Pretoria, South Africa Email: michaelburke@ieee.org Nico Bos Dept. Electrical, Electronic and Computer...

  8. NPP Grassland: Beacon Hill, U.K., 1972-1993, R1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains two ASCII text files, one providing productivity measurements for a chalk grassland on Beacon Hill, West Sussex, U.K. (50.92 N, -0.85 W) and...

  9. Multi-kW Uplink Fiber-Laser Beacon with Agile Signal Format, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration —  Laser beacons with scalable powers are needed for ground to deep-space optical communication uplinks. They serve as absolute reference for tracking of spacecraft...

  10. Multi-kW Uplink Fiber-Laser Beacon with Agile Signal Format, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Uplink Laser Beacons for deep-space communication, can benefit greatly from migration to the 1010-1030nm wavelengths, via use of Silicon-APDs on the spacecraft...

  11. 76 FR 65216 - Beacon Medical Services, LLC, Aurora, CO; Notice of Negative Determination Regarding Application...

    Science.gov (United States)

    2011-10-20

    ... coders'' at Beacon Medical Services, LLC, Aurora, Colorado, states that ``our jobs were outsourced to... shift in production by such workers' firm or subdivision to a foreign country of articles like or...

  12. Bluetooth Low Energy Beacon Performance and Utility in a Car Location Memory Aid Setting

    OpenAIRE

    Sætre, Karsten Andre Skogstad

    2018-01-01

    This project explores the usefulness and performance of BLE Bluetooth beacons. This is done through an experiment conducted in cooperation with a fellow student. The results reveal weaknesses in performance, but also potential. Within the constraints of those weaknesses I construct a memory aid prototype Android application, CaRemember, as a proof of concept in order to demonstrate a potentially useful use case that make use of BLE Bluetooth beacons.

  13. Quick acquisition and recognition method for the beacon in deep space optical communications.

    Science.gov (United States)

    Wang, Qiang; Liu, Yuefei; Ma, Jing; Tan, Liying; Yu, Siyuan; Li, Changjiang

    2016-12-01

    In deep space optical communications, it is very difficult to acquire the beacon given the long communication distance. Acquisition efficiency is essential for establishing and holding the optical communication link. Here we proposed a quick acquisition and recognition method for the beacon in deep optical communications based on the characteristics of the deep optical link. To identify the beacon from the background light efficiently, we utilized the maximum similarity between the collecting image and the reference image for accurate recognition and acquisition of the beacon in the area of uncertainty. First, the collecting image and the reference image were processed by Fourier-Mellin. Second, image sampling and image matching were applied for the accurate positioning of the beacon. Finally, the field programmable gate array (FPGA)-based system was used to verify and realize this method. The experimental results showed that the acquisition time for the beacon was as fast as 8.1s. Future application of this method in the system design of deep optical communication will be beneficial.

  14. Accelerated Adoption of Advanced Health Information Technology in Beacon Community Health Centers.

    Science.gov (United States)

    Jones, Emily; Wittie, Michael

    2015-01-01

    To complement national and state-level HITECH Act programs, 17 Beacon communities were funded to fuel community-wide use of health information technology to improve quality. Health centers in Beacon communities received supplemental funding. This article explores the association between participation in the Beacon program and the adoption of electronic health records. Using the 2010-2012 Uniform Data System, trends in health information technology adoption among health centers located within and outside of Beacon communities were explored using differences in mean t tests and multivariate logistic regression. Electronic health record adoption was widespread and rapidly growing in all health centers, especially quality improvement functionalities: structured data capture, order and results management, and clinical decision support. Adoption lagged for functionalities supporting patient engagement, performance measurement, care coordination, and public health. The use of advanced functionalities such as care coordination grew faster in Beacon health centers, and Beacon health centers had 1.7 times higher odds of adopting health records with basic safety and quality functionalities in 2010-2012. Three factors likely underlie these findings: technical assistance, community-wide activation supporting health information exchange, and the layering of financial incentives. Additional technical assistance and community-wide activation is needed to support the use of functionalities that are currently lagging. © Copyright 2015 by the American Board of Family Medicine.

  15. [The use of molecular biology techniques in the articles published in Revista Médica de Chile].

    Science.gov (United States)

    Herskovic, V; Jacard, M; Reyes, H

    2000-04-01

    Molecular biology is a new branch of biological sciences, with novel laboratory techniques that are being progressively applied into biomedical and clinical research and, furthermore, into medical practice. To evaluate the use of molecular biology techniques in Chilean biomedical and clinical research and its evolution in the recent decade. All papers published as research articles, clinical experiences or case reports, in Revista Médica de Chile, during two time periods: 1987-1989 and 1997-1999, were reviewed to find out whether molecular biology techniques had been used or not. This journal publishes roughly 40% of papers generated in Chile, in biomedical or clinical topics, while another 15% appears in foreign journals. Among 341 papers published in 1987-1989, 57 (16.7%) had used one or more molecular biology techniques; in contrast, among 318 papers published in 1997-1999, 91 (28.8%) had used them (p molecular biology techniques were research articles. Immunology, genetics, endocrinology, hematology, hepatology and rheumatology were the specialties providing a greater number and proportion of papers using molecular biology techniques. Chilean universities were the main institutions sponsoring these articles and FONDECYT (the Chilean Government Research Granting Office) was the main source of funding. The University of Chile (State-owned) provided most centers where these publications had been generated, followed by the Pontifical Catholic University of Chile. Molecular biology techniques have been rapidly and progressively incorporated as research tools in biomedicine and clinical medicine, in Chile. At the present time, these techniques are predominantly used in research conducted in University settings and funded by Governmental research grants.

  16. Role of Artificial Intelligence Techniques (Automatic Classifiers) in Molecular Imaging Modalities in Neurodegenerative Diseases.

    Science.gov (United States)

    Cascianelli, Silvia; Scialpi, Michele; Amici, Serena; Forini, Nevio; Minestrini, Matteo; Fravolini, Mario Luca; Sinzinger, Helmut; Schillaci, Orazio; Palumbo, Barbara

    2017-01-01

    Artificial Intelligence (AI) is a very active Computer Science research field aiming to develop systems that mimic human intelligence and is helpful in many human activities, including Medicine. In this review we presented some examples of the exploiting of AI techniques, in particular automatic classifiers such as Artificial Neural Network (ANN), Support Vector Machine (SVM), Classification Tree (ClT) and ensemble methods like Random Forest (RF), able to analyze findings obtained by positron emission tomography (PET) or single-photon emission tomography (SPECT) scans of patients with Neurodegenerative Diseases, in particular Alzheimer's Disease. We also focused our attention on techniques applied in order to preprocess data and reduce their dimensionality via feature selection or projection in a more representative domain (Principal Component Analysis - PCA - or Partial Least Squares - PLS - are examples of such methods); this is a crucial step while dealing with medical data, since it is necessary to compress patient information and retain only the most useful in order to discriminate subjects into normal and pathological classes. Main literature papers on the application of these techniques to classify patients with neurodegenerative disease extracting data from molecular imaging modalities are reported, showing that the increasing development of computer aided diagnosis systems is very promising to contribute to the diagnostic process.

  17. Molecular Techniques for the Detection of Organisms in Aquatic Environments, with Emphasis on Harmful Algal Bloom Species.

    Science.gov (United States)

    Medlin, Linda K; Orozco, Jahir

    2017-05-22

    Molecular techniques to detect organisms in aquatic ecosystems are being gradually considered as an attractive alternative to standard laboratory methods. They offer faster and more accurate means of detecting and monitoring species, with respect to their traditional homologues based on culture and microscopic counting. Molecular techniques are particularly attractive when multiple species need to be detected and/or are in very low abundance. This paper reviews molecular techniques based on whole cells, such as microscope-based enumeration and Fluorescence In-Situ Hybridization (FISH) and molecular cell-free formats, such as sandwich hybridization assay (SHA), biosensors, microarrays, quantitative polymerase chain reaction (qPCR) and real time PCR (RT-PCR). Those that combine one or several laboratory functions into a single integrated system (lab-on-a-chip) and techniques that generate a much higher throughput data, such as next-generation systems (NGS), were also reviewed. We also included some other approaches that enhance the performance of molecular techniques. For instance, nano-bioengineered probes and platforms, pre-concentration and magnetic separation systems, and solid-phase hybridization offer highly pre-concentration capabilities. Isothermal amplification and hybridization chain reaction (HCR) improve hybridization and amplification techniques. Finally, we presented a study case of field remote sensing of harmful algal blooms (HABs), the only example of real time monitoring, and close the discussion with future directions and concluding remarks.

  18. Synthesis and Bioconjugation of Gold Nanoparticles as Potential Molecular Probes for Light-Based Imaging Techniques

    Directory of Open Access Journals (Sweden)

    Raja Gopal Rayavarapu

    2007-01-01

    Full Text Available We have synthesized and characterized gold nanoparticles (spheres and rods with optical extinction bands within the “optical imaging window.” The intense plasmon resonant driven absorption and scattering peaks of these nanoparticles make them suitable as contrast agents for optical imaging techniques. Further, we have conjugated these gold nanoparticles to a mouse monoclonal antibody specific to HER2 overexpressing SKBR3 breast carcinoma cells. The bioconjugation protocol uses noncovalent modes of binding based on a combination of electrostatic and hydrophobic interactions of the antibody and the gold surface. We discuss various aspects of the synthesis and bioconjugation protocols and the characterization results of the functionalized nanoparticles. Some proposed applications of these potential molecular probes in the field of biomedical imaging are also discussed.

  19. Advanced microscopic and histochemical techniques: diagnostic tools in the molecular era of myology

    Directory of Open Access Journals (Sweden)

    G Meola

    2009-06-01

    Full Text Available Over the past two centuries, myology (i.e. the basic and clinical science of muscle and muscle disease has passed through 3 stages of development: the classical period, the modern stage and the molecular era. The classical period spans the last part of nineteenth century and the earlier part of the twentieth century. During this time, several major muscle disease were clinically and pathologically characterized, including Duchenne muscular dystrophy (DMD, myotonic dystrophy (DM and facioscapulohumeral dystrophy (FSHD. The modern stage in the second half of the twentieth century is characterized by the adaptation of histo and cytochemical techniques to the study of muscle biopsies. These tools improved the diagnostic accuracy and made possible the identification of new changes and structures (Engel and Cunningham, 1963; Scarlato, 1975.

  20. Electrical characterization of ensemble of GaN nanowires grown by the molecular beam epitaxy technique

    International Nuclear Information System (INIS)

    Kolkovsky, Vl.; Zytkiewicz, Z. R.; Sobanska, M.; Klosek, K.

    2013-01-01

    High quality Schottky contacts are formed on GaN nanowires (NWs) structures grown by the molecular beam epitaxy technique on Si(111) substrate. The current-voltage characteristics show the rectification ratio of about 10 3 and the leakage current of about 10 −4 A/cm 2 at room temperature. From the capacitance-voltage measurements the free carrier concentration in GaN NWs is determined as about 10 16 cm −3 . Two deep levels (H200 and E280) are found in the structures containing GaN NWs. H200 is attributed to an extended defect located at the interface between the substrate and SiN x or near the sidewalls at the bottom of the NWs whereas E280 is tentatively assigned to a gallium-vacancy- or nitrogen interstitials-related defect

  1. Vibrio parahaemolyticus: a review on the pathogenesis, prevalence, and advance molecular identification techniques

    Science.gov (United States)

    Letchumanan, Vengadesh; Chan, Kok-Gan; Lee, Learn-Han

    2014-01-01

    Vibrio parahaemolyticus is a Gram-negative halophilic bacterium that is found in estuarine, marine and coastal environments. V. parahaemolyticus is the leading causal agent of human acute gastroenteritis following the consumption of raw, undercooked, or mishandled marine products. In rare cases, V. parahaemolyticus causes wound infection, ear infection or septicaemia in individuals with pre-existing medical conditions. V. parahaemolyticus has two hemolysins virulence factors that are thermostable direct hemolysin (tdh)-a pore-forming protein that contributes to the invasiveness of the bacterium in humans, and TDH-related hemolysin (trh), which plays a similar role as tdh in the disease pathogenesis. In addition, the bacterium is also encodes for adhesions and type III secretion systems (T3SS1 and T3SS2) to ensure its survival in the environment. This review aims at discussing the V. parahaemolyticus growth and characteristics, pathogenesis, prevalence and advances in molecular identification techniques. PMID:25566219

  2. Pyrite: A blender plugin for visualizing molecular dynamics simulations using industry-standard rendering techniques.

    Science.gov (United States)

    Rajendiran, Nivedita; Durrant, Jacob D

    2018-05-05

    Molecular dynamics (MD) simulations provide critical insights into many biological mechanisms. Programs such as VMD, Chimera, and PyMOL can produce impressive simulation visualizations, but they lack many advanced rendering algorithms common in the film and video-game industries. In contrast, the modeling program Blender includes such algorithms but cannot import MD-simulation data. MD trajectories often require many gigabytes of memory/disk space, complicating Blender import. We present Pyrite, a Blender plugin that overcomes these limitations. Pyrite allows researchers to visualize MD simulations within Blender, with full access to Blender's cutting-edge rendering techniques. We expect Pyrite-generated images to appeal to students and non-specialists alike. A copy of the plugin is available at http://durrantlab.com/pyrite/, released under the terms of the GNU General Public License Version 3. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  3. Molecular techniques to distinguish morphologically similar Hydrilla verticillata, Egeria densa, Elodea nuttallii, and Elodea canadensis

    Science.gov (United States)

    Rybicki, Nancy B.; Kirshtein, Julie D.; Voytek, Mary A.

    2013-01-01

    The four submerged aquatic species, hydrilla (Hydrilla verticillata [monoecious and dioecious]), Brazilian waterweed (Egeria densa), Canadian waterweed (Elodea canadensis), and western waterweed (Elodea nuttallii), are difficult to positively identify because of their morphological similarity to each other, resulting in possible misidentification. This limits our ability to understand their past and present distribution, which is important in aquatic plant management. We investigated a molecular technique to identify these species, which are problematic because of their invasive nature on multiple continents. Approximately 100 samples of these species, ranging in age from 40-yr-old herbarium samples to recently collected plants, were collected from regions across the United States. The distribution and range of the samples collected in this research were compared to those reported in the literature. We confirmed information on the current wide distribution of both hydrilla biotypes in the United States and discovered that hydrilla had actually invaded the waterways near Washington, DC 6 yr earlier than originally reported. In addition, we found evidence of the confusion, dating back to the 1980s, between Canadian waterweed and western waterweed in the mid-Atlantic region of the United States. Canadian waterweed was previously reported as common and western waterweed as rare; however, our samples indicate the opposite is true. This information indicates there is a need for investigators to anticipate the spread of hydrilla populations to northern U.S. waterways, where it will compete with existing plant species, including Canadian and western waterweeds. Our ability to confirm distribution and pace of spread of invasive and noninvasive species will improve with increased application of molecular techniques.

  4. Application of molecular techniques for the assessment of microorganism diversity on cultural heritage objects.

    Science.gov (United States)

    Otlewska, Anna; Adamiak, Justyna; Gutarowska, Beata

    2014-01-01

    As a result of their unpredictable ability to adapt to varying environmental conditions, microorganisms inhabit different types of biological niches on Earth. Owing to the key role of microorganisms in many biogeochemical processes, trends in modern microbiology emphasize the need to know and understand the structure and function of complex microbial communities. This is particularly important if the strategy relates to microbial communities that cause biodeterioration of materials that constitute our cultural heritage. Until recently, the detection and identification of microorganisms inhabiting objects of cultural value was based only on cultivation-dependent methods. In spite of many advantages, these methods provide limited information because they identify only viable organisms capable of growth under standard laboratory conditions. However, in order to carry out proper conservation and renovation, it is necessary to know the complete composition of microbial communities and their activity. This paper presents and characterizes modern techniques such as genetic fingerprinting and clone library construction for the assessment of microbial diversity based on molecular biology. Molecular methods represent a favourable alternative to culture-dependent methods and make it possible to assess the biodiversity of microorganisms inhabiting technical materials and cultural heritage objects.

  5. Exploration of disulfiram dealings with calf thymus DNA using spectroscopic, electrochemical and molecular docking techniques

    International Nuclear Information System (INIS)

    Subastri, A.; Durga, A.; Harikrishna, K.; Sureshkumar, M.; Jeevaratnam, K.; Girish, K.S.; Thirunavukkarasu, C.

    2016-01-01

    Disulfiram (C 10 H 20 N 2 S 4 ) is an acetaldehyde dehydrogenase inhibitor used in the treatment of chronic alcoholism and it has also been subjected to the clinical trial for cancer in recent times. However, there is no report on the binding effect of this emerging drug with DNA. Hence, the present investigation was taken up to study the binding effect of disulfiram on DNA under physiological conditions. UV–vis absorption spectroscopy, fluorescence emission spectroscopy, circular dichroism spectroscopy, cyclic voltammetry and molecular docking techniques were employed to determine the interaction mode of disulfiram with DNA. Further, DNA cleavage property of disulfiram was carried out by using agarose gel electrophoresis. The UV–vis absorption, emission and cyclic voltammetry measurements revealed that disulfiram showed the intercalative mode of interaction with DNA. The circular dichroism study exhibited structural changes of partial transition from B-conformation to A-conformation in DNA upon addition of disulfiram. Molecular docking study of disulfiram with DNA depicted intercalative mode of binding by formation of hydrogen and hydrophobic interaction along with docking score of −3.07 kcal/mol. The DNA cleavage study revealed that low concentration of disulfiram (50 µM) protected the DNA from oxidative damage sequentially, while high concentration of disulfiram (100 µM) showed less protective activity. Conversely, it caused DNA damage in the presence of hydroxyl radical oxidative system. Hence, the results obtained from the present investigations provide detailed discernment into DNA interaction effects of disulfiram.

  6. Evaluation of growth conditions and DNA extraction techniques used in the molecular analysis of dermatophytes.

    Science.gov (United States)

    Gnat, S; Nowakiewicz, A; Ziółkowska, G; Trościańczyk, A; Majer-Dziedzic, B; Zięba, P

    2017-05-01

    Recent molecular methods for diagnosis of superficial mycoses have determined the need for a rapid and easy method of extracting DNA. The aim of study was to determine growth conditions and techniques of DNA extraction for Microsporum canis, Trichophyton mentagrophytes and T. verrucosum. Samples were prepared of each of the DNA extraction methods (phenol-chloroform, CTAB and four different kits) for all of the incubation periods (4, 7 and 10 days) of the cultures on the solid and in the liquid medium. The highest DNA concentrations were obtained using the phenol-chloroform method. The concentration of DNA extracted with the CTAB method accounted for 62·21%, for kits it corresponded from 35·53 to 15·41%. The analysis of the DNA weight yield revealed the highest isolation efficiency of the phenol-chloroform method, 1 mg of mycelium yielded 223·8 μg DNA. Lower DNA yield (by 39·32%) was obtained with the CTAB method; in the case of kits by 68·46-85·32%. In most of the techniques, the DNA yield on the solid medium was higher. In summary, the highest DNA yield was noted in the 7-day cultures and extraction with the phenol-chloroform method. Importantly, the type of culture was not relevant for the diagnostic result. Most mycoses are caused by fungi that reside in nature. The severity of the infection depends on the pathogenic attributes, socioeconomic factors and local environmental conditions. Recent diagnosis increasingly relies on not only the clinical features. Molecular identifications have determined the need for a rapid and easy method of extracting DNA. Usually two factors have to be considered: maximize the DNA yield and ensure that the extracted DNA is susceptible to enzymatic reactions. These data suggest that phenol-chloroform methods and a 7-day culture period may be useful for validation and constitute the first step of molecular diagnosis of dermatophytes. © 2017 The Society for Applied Microbiology.

  7. Nuclear science fights malaria. Radiation and molecular techniques can play targeted roles

    International Nuclear Information System (INIS)

    Groth, Steffen; Khan, Baldip; Robinson, Alan; Hendrichs, Jorge

    2001-01-01

    Malaria is the most important insect transmitted disease. Globally there are 300 to 500 million clinical cases of malaria a year. They result in two million deaths per year (one every 30 seconds), more than 90% of which occur in sub-Saharan Africa. More than 90% of those affected are children less than five years old. The economic impact of the disease is felt disproportionately by poor families who may spend a fourth of their annual income on prevention and control measures. The causative agents are parasites of the genus Plasmodium and they are transmitted only by female mosquitoes of the genus Anopheles. Among key strategies to control malaria are the surveillance of anti-malarial drug efficacy through monitoring the levels of drug resistance, and the reduction of mosquito populations. Nuclear techniques can play important roles in these efforts to combat malaria. This article reports on IAEA activities associated with drug-resistant malaria and describes how molecular methods making use of radioactive isotopes can provide a great advantage in the diagnosis of resistance. The article further presents the IAEA's plans for initiating a research programme to assess the feasibility of developing the Sterile Insect Technique (SIT) as a complementary method to control the vector of malaria

  8. Identification of Viable Helicobacter pylori in Drinking Water Supplies by Cultural and Molecular Techniques.

    Science.gov (United States)

    Santiago, Paula; Moreno, Yolanda; Ferrús, M Antonía

    2015-08-01

    Helicobacter pylori is one of the most common causes of chronic bacterial infection in humans, directly related to peptic ulcer and gastric cancer. It has been suggested that H. pylori can be acquired through different transmission routes, including water. In this study, culture and qPCR were used to detect and identify the presence of H. pylori in drinking water. Furthermore, the combined techniques PMA-qPCR and DVC-FISH were applied for detection of viable cells of H. pylori. Among 24 drinking water samples, 16 samples were positive for the presence of H. pylori, but viable cells were only detected in six samples. Characteristic colonies, covered by a mass of bacterial unspecific growth, were observed on selective agar plates from an only sample, after enrichment. The mixed culture was submitted to DVC-FISH and qPCR analysis, followed by sequencing of the amplicons. Molecular techniques confirmed the growth of H. pylori on the agar plate. Our results demonstrate for the first time that H. pylori can survive and be potentially infective in drinking water, showing that water distribution systems could be a potential route for H. pylori transmission. © 2015 John Wiley & Sons Ltd.

  9. Exploration of the speleotherapeutic potential through the cellular and molecular biology techniques

    Directory of Open Access Journals (Sweden)

    Munteanu Constantin

    2011-02-01

    Full Text Available Objective: Exploring the speleotherapy effects on morphology and physiology of dermal and pulmonary fibroblast obtained from Wistar rats tissue in normal conditions and after induction of experimental “astma” awareness with ovalbumin. Materials and methods: Before initiation of dermal and pulmonary fibroblast cultures, 60 of Wistar rats 75-100 g were divided into two groups: control and sensitized with ovalalbumin. 10 animals of each group were sent to Cacica and Dej salt mines and maintained in a speleotherapy regime. Another 10 animals in each group were monitored separately in INRMFB Biobase . Dermal and pulmonary fibroblast cultures were initiated by enzymatic techniques from appropriate tissue taken of each group Wistar rats. Morphological monitoring was done by phase contast microscopy; biochemical and molecular changes of cultures obtained from animals treated speleothropic compared to control, was experimental establised by electrophoresis and Western Blotting techniques.Results: Experimental data revealed the expression of several proteins after the speleotherapeutic treatment. These data were analysed compared with control, using a specific software.Conclusions: Speleotherapeutic treatment of Wistar rats caused significant differences in morphology and protein expression of dermal and pulmonary fibroblatst grown in the laboratory. These differences support the protective effects of speleotherapy compared with data obtained from animals untreated and sensitized with ovalbumin, having induced experimental asthma status.

  10. Electrochemical microfluidic chip based on molecular imprinting technique applied for therapeutic drug monitoring.

    Science.gov (United States)

    Liu, Jiang; Zhang, Yu; Jiang, Min; Tian, Liping; Sun, Shiguo; Zhao, Na; Zhao, Feilang; Li, Yingchun

    2017-05-15

    In this work, a novel electrochemical detection platform was established by integrating molecularly imprinting technique with microfluidic chip and applied for trace measurement of three therapeutic drugs. The chip foundation is acrylic panel with designed grooves. In the detection cell of the chip, a Pt wire is used as the counter electrode and reference electrode, and a Au-Ag alloy microwire (NPAMW) with 3D nanoporous surface modified with electro-polymerized molecularly imprinted polymer (MIP) film as the working electrode. Detailed characterization of the chip and the working electrode was performed, and the properties were explored by cyclic voltammetry and electrochemical impedance spectroscopy. Two methods, respectively based on electrochemical catalysis and MIP/gate effect were employed for detecting warfarin sodium by using the prepared chip. The linearity of electrochemical catalysis method was in the range of 5×10 -6 -4×10 -4 M, which fails to meet clinical testing demand. By contrast, the linearity of gate effect was 2×10 -11 -4×10 -9 M with remarkably low detection limit of 8×10 -12 M (S/N=3), which is able to satisfy clinical assay. Then the system was applied for 24-h monitoring of drug concentration in plasma after administration of warfarin sodium in rabbit, and the corresponding pharmacokinetic parameters were obtained. In addition, the microfluidic chip was successfully adopted to analyze cyclophosphamide and carbamazepine, implying its good versatile ability. It is expected that this novel electrochemical microfluidic chip can act as a promising format for point-of-care testing via monitoring different analytes sensitively and conveniently. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Exploration of disulfiram dealings with calf thymus DNA using spectroscopic, electrochemical and molecular docking techniques

    Energy Technology Data Exchange (ETDEWEB)

    Subastri, A.; Durga, A. [Department of Biochemistry and Molecular Biology, Pondicherry University, Puducherry 605014 (India); Harikrishna, K.; Sureshkumar, M. [Centre for Bioinformatics, Pondicherry University, Puducherry 605014 (India); Jeevaratnam, K. [Department of Biochemistry and Molecular Biology, Pondicherry University, Puducherry 605014 (India); Girish, K.S. [Department of Studies & Research in Biochemistry, Tumkur University, Tumkur, Karnataka (India); Thirunavukkarasu, C., E-mail: tchinnasamy@hotmail.com [Department of Biochemistry and Molecular Biology, Pondicherry University, Puducherry 605014 (India)

    2016-02-15

    Disulfiram (C{sub 10}H{sub 20}N{sub 2}S{sub 4}) is an acetaldehyde dehydrogenase inhibitor used in the treatment of chronic alcoholism and it has also been subjected to the clinical trial for cancer in recent times. However, there is no report on the binding effect of this emerging drug with DNA. Hence, the present investigation was taken up to study the binding effect of disulfiram on DNA under physiological conditions. UV–vis absorption spectroscopy, fluorescence emission spectroscopy, circular dichroism spectroscopy, cyclic voltammetry and molecular docking techniques were employed to determine the interaction mode of disulfiram with DNA. Further, DNA cleavage property of disulfiram was carried out by using agarose gel electrophoresis. The UV–vis absorption, emission and cyclic voltammetry measurements revealed that disulfiram showed the intercalative mode of interaction with DNA. The circular dichroism study exhibited structural changes of partial transition from B-conformation to A-conformation in DNA upon addition of disulfiram. Molecular docking study of disulfiram with DNA depicted intercalative mode of binding by formation of hydrogen and hydrophobic interaction along with docking score of −3.07 kcal/mol. The DNA cleavage study revealed that low concentration of disulfiram (50 µM) protected the DNA from oxidative damage sequentially, while high concentration of disulfiram (100 µM) showed less protective activity. Conversely, it caused DNA damage in the presence of hydroxyl radical oxidative system. Hence, the results obtained from the present investigations provide detailed discernment into DNA interaction effects of disulfiram.

  12. BBUNS: Bluetooth Beacon-Based Underground Navigation System to Support Mine Haulage Operations

    Directory of Open Access Journals (Sweden)

    Jieun Baek

    2017-11-01

    Full Text Available A Bluetooth beacon-based underground navigation system (BBUNS was developed to identify the optimal haul road in an underground mine, track the locations of dump trucks, and display this information on mobile devices. A three-dimensional (3-D geographic information system (GIS database of the haul roads in an underground mine was constructed, and the travel time for each section was calculated. A GIS database was also constructed for 50 Bluetooth beacons that were installed along the haul roads. An Android-based BBUNS application was developed to visualize the current location of each dump truck and the optimal haul road to the destination on mobile devices, using the Bluetooth beacon system that was installed in the underground mine. Whenever the BBUNS recognized all of the Bluetooth beacons installed in the underground mine, it could provide the dump truck drivers with information on the current location and the two-dimensional (2-D and 3-D haul road properties. The operating time of each dump truck and the time spent on each unit task could be analyzed using recorded data on the times when Bluetooth beacon signals were recognized by the BBUNS. The underground mine navigation system that was developed in this study can contribute to the improvement of haul operation efficiency and productivity.

  13. Adaptive Beaconing in Mobility Aware Clustering Based MAC Protocol for Safety Message Dissemination in VANET

    Directory of Open Access Journals (Sweden)

    Nishu Gupta

    2017-01-01

    Full Text Available Majority of research contributions in wireless access in vehicular environment (WAVE/IEEE 802.11p standard focus on life critical safety-related applications. These applications require regular status update of vehicle’s position referred to as beaconing. Periodic beaconing in vehicle to vehicle communication leads to severe network congestion in the communication channel. The condition worsens under high vehicular density where it impacts reliability and upper bound latency of safety messages. In this paper, WAVE compliant enhancement to the existing IEEE 802.11p protocol is presented which targets prioritized delivery of safety messages while simultaneously provisioning the dissemination of nonsafety messages. Proposed scheme relies on dynamic generation of beacons to mitigate channel congestion and inefficient bandwidth utilization by reducing transmission frequency of beacons. Through the use of clustering mechanism, different beaconing frequencies and different data transmission rates are assigned to prioritize vehicular mobility. Through extensive simulation results, the performance of the proposed approach is evaluated in terms of a wide range of quality of service (QoS parameters for two different transmission ranges. Results show that the proposed protocol provides significant enhancement and stability of the clustered topology in vehicular ad hoc network over existing standard and other protocols with similar applications.

  14. Biomechanical testing of new meniscal repair techniques containing ultra high-molecular weight polyethylene suture.

    Science.gov (United States)

    Barber, F Alan; Herbert, Morley A; Schroeder, F Alexander; Aziz-Jacobo, Jorge; Sutker, Michael J

    2009-09-01

    To evaluate the biomechanical characteristics of current meniscal repair techniques containing ultra high-molecular weight polyethylene (UHMWPE) suture with and without cyclic loading. Vertical longitudinal cuts made in porcine menisci were secured with a single repair device. Noncycled and cycled (500 cycles) biomechanical tests were performed on the following groups: group 1, No. 2-0 Mersilene vertical suture (Ethicon, Somerville, NJ); group 2, No. 2-0 Orthocord vertical suture (DePuy Mitek, Westwood, MA); group 3, No. 0 Ultrabraid vertical suture (Smith & Nephew Endoscopy, Andover, MA); group 4, No. 2-0 FiberWire vertical suture (Arthrex, Naples, FL); group 5, vertically oriented mattress suture by use of an Ultra FasT-Fix device (Smith & Nephew Endoscopy) with No. 0 Ultrabraid; group 6, vertically oriented mattress suture by use of a RapidLoc A2 device (DePuy Mitek) with No. 2-0 Orthocord suture; group 7, vertically oriented stitch by use of a MaxFire device with MaxBraid PE suture (Biomet Sports Medicine, Warsaw, IN); and group 8, an obliquely oriented stitch of No. 0 UHMWPE suture inserted by use of a CrossFix device (Cayenne Medical, Scottsdale, AZ). Endpoints were failure loads, failure modes, stiffness, and cyclic displacement. Mean single-pull loads were calculated for Ultra FasT-Fix (121 N), FiberWire (110 N), MaxFire (130 N), Mersilene (84 N), Orthocord (124 N), RapidLoc A2 (86 N), CrossFix (77 N), and Ultrabraid (109 N). After 500 cyclic loads, the Orthocord (222 N) repair was stronger than the others: Ultra FasT-Fix (110 N), FiberWire (117 N), MaxFire (132 N), Mersilene (89 N), RapidLoc A2 (108 N), CrossFix (95 N), and Ultrabraid (126 N) (P Fix, RapidLoc A2, and MaxFire) were comparable to the isolated UHMWPE-containing suture repairs on single-failure load testing. UHMWPE-containing suture repairs are stronger than braided polyester suture repairs, but pure UHMWPE suture (Ultrabraid) elongated more during cycling. Orthocord suture is significantly

  15. Molecular basis of structural make-up of feeds in relation to nutrient absorption in ruminants, revealed with advanced molecular spectroscopy: A review on techniques and models

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, Md. Mostafizar [Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; Yu, Peiqiang [Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

    2017-01-31

    Progress in ruminant feed research is no more feasible only based on wet chemical analysis, which is merely able to provide information on chemical composition of feeds regardless of their digestive features and nutritive value in ruminants. Studying internal structural make-up of functional groups/feed nutrients is often vital for understanding the digestive behaviors and nutritive values of feeds in ruminant because the intrinsic structure of feed nutrients is more related to its overall absorption. In this article, the detail information on the recent developments in molecular spectroscopic techniques to reveal microstructural information of feed nutrients and the use of nutrition models in regards to ruminant feed research was reviewed. The emphasis of this review was on (1) the technological progress in the use of molecular spectroscopic techniques in ruminant feed research; (2) revealing spectral analysis of functional groups of biomolecules/feed nutrients; (3) the use of advanced nutrition models for better prediction of nutrient availability in ruminant systems; and (4) the application of these molecular techniques and combination of nutrient models in cereals, co-products and pulse crop research. The information described in this article will promote better insight in the progress of research on molecular structural make-up of feed nutrients in ruminants.

  16. Perlecan domain V therapy for stroke: a beacon of hope?

    Science.gov (United States)

    Bix, Gregory J

    2013-03-20

    The sad reality is that in the year 2012, people are still dying or suffering from the extreme morbidity of ischemic stroke. This tragedy is only compounded by the graveyard full of once promising new therapies. While it is indeed true that the overall mortality from stroke has declined in the United States, perhaps due to increased awareness of stroke symptoms by both the lay public and physicians, it is clear that better therapies are needed. In this regard, progress has been tremendously slowed by the simple fact that experimental models of stroke and the animals that they typically employ, rats and mice, do not adequately represent human stroke. Furthermore, the neuroprotective therapeutic approach, in which potential treatments are administered with the hope of preventing the spread of dying neurons that accompanies a stroke, typically fail for a number of reasons such as there is simply more brain matter to protect in a human than there is in a rodent! For this reason, there has been somewhat of a shift in stroke research away from neuroprotection and toward a neurorepair approach. This too may be problematic in that agents that might foster brain repair could be acutely deleterious or neurotoxic and vice versa, making the timing of treatment administration after stroke critical. Therefore, in our efforts to discover a new stroke therapy, we decided to focus on identifying brain repair elements that were (1) endogenously and actively generated in response to stroke in both human and experimental animal brains, (2) present acutely and chronically after ischemic stroke, suggesting that they could have a role in acute neuroprotection and chronic neurorepair, and (3) able to be administered peripherally and reach the site of stroke brain injury. In this review, I will discuss the evidence that suggests that perlecan domain V may be just that substance, a potential beacon of hope for stroke patients.

  17. A Partnership Training Program in Breast Cancer Research Using Molecular Imaging Techniques

    National Research Council Canada - National Science Library

    Wang, Paul C

    2006-01-01

    In the first year of this training grant, five faculty members from different departments at the Howard University were trained in molecular imaging with the faculty at the In Vivo Cellular Molecular...

  18. Comparison of the detection of periodontal pathogens in bacteraemia after tooth brushing by culture and molecular techniques

    OpenAIRE

    Mar?n, Mar?a-Jose; Figuero, Elena; Gonz?lez, Itziar; O?Connor, Ana; Diz, Pedro; ?lvarez, Maximiliano; Herrera, David; Sanz, Mariano

    2016-01-01

    Background The prevalence and amounts of periodontal pathogens detected in bacteraemia samples after tooth brushing-induced by means of four diagnostic technique, three based on culture and one in a molecular-based technique, have been compared in this study. Material and Methods Blood samples were collected from thirty-six subjects with different periodontal status (17 were healthy, 10 with gingivitis and 9 with periodontitis) at baseline and 2 minutes after tooth brushing. Each sample was a...

  19. Molecular and microscopic techniques for detection of Sarcocystis neurona sporocysts in fecal samples.

    Science.gov (United States)

    Elsheikha, Hany M; Murphy, Alice J; Trembley, Sarah J; Mansfield, Linda S; Ghanam, Mohammad S; el-Garhy, Manal F

    2006-08-01

    Diagnosis of Sarcocystis sp. in the definitive host is generally by microscopic detection of the sporocysts in feces. This method is insensitive and cannot differentiate between species because sporocysts lack specific staining criteria. The hypothesis suggested that molecular techniques provide better alternatives to classical detection of Sarcocystis sporocysts. The sensitivity of two PCR assays was compared to one another and to microscopic examination by conventional fecal flotation and Diamant-Fuchsin staining procedures for detection of sporocysts spiked into mice feces. PCR1 assay using LSM1 & LSM2 primers that amplified 496 bp of the ssurRNA gene was more sensitive than the PCR2 method using JNB25 and JD396 primers that amplified 334 bp of a RAPD-derived marker. PCRI gave positive results with 200 microl of fecal suspension spiked with as little as 5 sporocysts compared to 75 sporocysts detected by JNB25 & JD396 primers. PCRI was more sensitive than conventional microscopy. PCR1 or PCR2 followed by sequencing or RFLP analysis not only detected Sarcocystis sporocysts in feces but also enabled to ascertain the genotype of the species as S. neurona.

  20. External Quality Assessment for the Detection of Chlamydia trachomatis in Urine Using Molecular Techniques in Belgium

    Directory of Open Access Journals (Sweden)

    Bernard China

    2015-01-01

    Full Text Available Chlamydia trachomatis is a major cause of sexually transmitted bacterial disease worldwide. C. trachomatis is an intracellular bacterium and its growth in vitro requires cell culture facilities. The diagnosis is based on antigen detection and more recently on molecular nucleic acid amplification techniques (NAAT that are considered fast, sensitive, and specific. In Belgium, External Quality Assessment (EQA for the detection of C. trachomatis in urine by NAAT was introduced in 2008. From January 2008 to June 2012, nine surveys were organized. Fifty-eight laboratories participated in at least one survey. The EQA panels included positive and negative samples. The overall accuracy was 75.4%, the overall specificity was 97.6%, and the overall sensitivity was 71.4%. Two major issues were observed: the low sensitivity (45.3% for the detection of low concentration samples and the incapacity of several methods to detect the Swedish variant of C. trachomatis. The reassuring point was that the overall proficiency of the Belgian laboratories tended to improve over time.

  1. Ex vivo irradiation of human blood to determine DNA damage using molecular techniques

    International Nuclear Information System (INIS)

    Montes, Angel; Agapito, Juan

    2014-01-01

    Biological dosimetry is the assessment of absorbed dose in individuals exposed to ionizing radiation from blood samples based on the radiation induced damage in cellular DNA. The aim of this study was to determine the damage in the DNA through the assessment of an experimental ex vivo assay using irradiated samples of human blood cells. For this purpose, blood samples were irradiated at low doses (<100 mGy) considering the following parameters: blood volume (3mL), temperature (37 °C) and incubation time (0.5, 2, 4, 8 and 24 h). Dose values were: 0, 12.5, 25 and 50 mGy using Cesium -137 gamma rays at 662 keV and a dose rate of 38.46 mGy/h. The qualitative damage in the genomic DNA was determined using agarose gel electrophoresis and polymerase chain reaction (PCR) for the p53 gene in a sequence of 133 pb of exon 7, related to the protein that acts in the cell repair process. The results of the qualitative analysis showed no degradation of genomic DNA; also an increase in the DNA concentration was observed up to the fourth hour of incubation, finding maximum values for all doses in the two samples. As a conclusion, the effects of ionizing radiation at doses used in this experiment do not generate a detectable damage, by means of molecular techniques such as those used in the present study. (authors).

  2. New understanding of rhizosphere processes enabled by advances in molecular and spatially resolved techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hess, Nancy J.; Paša-Tolić, Ljiljana; Bailey, Vanessa L.; Dohnalkova, Alice C.

    2017-06-01

    Understanding the role played by microorganisms within soil systems is challenged by the unique intersection of physics, chemistry, mineralogy and biology in fostering habitat for soil microbial communities. To address these challenges will require observations across multiple spatial and temporal scales to capture the dynamics and emergent behavior from complex and interdependent processes. The heterogeneity and complexity of the rhizosphere require advanced techniques that press the simultaneous frontiers of spatial resolution, analyte sensitivity and specificity, reproducibility, large dynamic range, and high throughput. Fortunately many exciting technical advancements are now available to inform and guide the development of new hypotheses. The aim of this Special issue is to provide a holistic view of the rhizosphere in the perspective of modern molecular biology methodologies that enabled a highly-focused, detailed view on the processes in the rhizosphere, including numerous, strong and complex interactions between plant roots, soil constituents and microorganisms. We discuss the current rhizosphere research challenges and knowledge gaps, as well as perspectives and approaches using newly available state-of-the-art toolboxes. These new approaches and methodologies allow the study of rhizosphere processes and properties, and rhizosphere as a central component of ecosystems and biogeochemical cycles.

  3. Detection of human filarial parasite Brugia malayi in dogs by histochemical staining and molecular techniques.

    Science.gov (United States)

    Ambily, V R; Pillai, Usha Narayana; Arun, R; Pramod, S; Jayakumar, K M

    2011-09-27

    Human filariasis caused by Brugia malayi is still a public health problem in many countries of Asia including India, Indonesia, Malaysia and Thailand. The World Health Organization (WHO) has targeted to eliminate filariasis by the year 2020 by Mass annual single dose Diethylcarbamazine Administration (MDA). Results of the MDA programme after the first phase was less satisfactory than expected. Malayan filariasis caused by B. malayi is endemic in the south of Thailand where domestic cat serves as the major reservoir host. There is no report about the occurrence of B. malayi in dogs. The present work was carried out to find out the incidence of microfilariasis in dogs and also to detect the presence of human filarial infection in dogs, if any. One hundred dogs above 6 months of age presented to the veterinary college Hospital, Mannuthy, Kerala, with clinical signs suggestive of microfilariasis - fever, anorexia, conjunctivitis, limb and scrotal oedema - were screened for microfilariae by wet film examination. Positive cases were subjected to Giemsa staining, histochemical staining and molecular techniques. Results of the study showed that 80% of dogs had microfilariasis; out of which 20% had sheathed microfilaria. Giemsa and histochemical staining character, PCR and sequencing confirmed it as B. malayi. High prevalence of B. malayi in dogs in this study emphasized the possible role of dogs in transmission of human filariasis. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Efficient Beacon Collision Resolution Procedure for IEEE 802.15.4 /Zigbee Wireless Personal Area Networks

    Directory of Open Access Journals (Sweden)

    Bassam A. Zafar

    2017-04-01

    Full Text Available While IEEE 802.15.4/Zigbee is a promising technology for Wireless Personal Area Networks, several transmission problems are not yet resolved. In particular, the problem of beacon transmission interferences is causing the device connection loss to the network. In order to resolve this problem, we present a new distributed and reactive procedure for beacon collision resolution. It is an extension of the alignment procedure to reorganize randomly the beacon transmission time when a collision has occurred. The detail of the proposed procedure will be fully described and analyzed. The performance of our approach is performed by simulations. The results show that our approach reduces the collision probability and the device disconnections consequently.

  5. Preliminary Observations of Ionospheric Structures using Ground Receivers and the COSMIC Radio Beacon

    Science.gov (United States)

    Garner, T. W.; Gaussiran, T. L., II; Bust, G. S.

    2006-11-01

    With the launch of the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) satellite constellation, a new era has begun for low-Earth-orbiting (LEO) satellite beacon research has begun. Each COSMIC satellite carries a radio beacon that can emit at 1066, 400, and 150 MHz. Coherent Ionospheric Doppler Receivers (CIDR) deployed at mid-latitudes observe the electron content and phase scintillation in the 400 and 150 MHz channels. In addition to high (Alaska and Greenland) and low (Peru) latitude systems, CIDRs are deployed in Austin, Texas, a chain across southern New York, Millstone Hill, and Wallops Island. This study presents preliminary observations of different ionospheric structures using CIDR receivers and the COSMIC radio beacon.

  6. Clinical and molecular analyses of Beckwith-Wiedemann syndrome: Comparison between spontaneous conception and assisted reproduction techniques.

    Science.gov (United States)

    Tenorio, Jair; Romanelli, Valeria; Martin-Trujillo, Alex; Fernández, García-Moya; Segovia, Mabel; Perandones, Claudia; Pérez Jurado, Luis A; Esteller, Manel; Fraga, Mario; Arias, Pedro; Gordo, Gema; Dapía, Irene; Mena, Rocío; Palomares, María; Pérez de Nanclares, Guiomar; Nevado, Julián; García-Miñaur, Sixto; Santos-Simarro, Fernando; Martinez-Glez, Víctor; Vallespín, Elena; Monk, David; Lapunzina, Pablo

    2016-10-01

    Beckwith-Wiedemann syndrome (BWS) is an overgrowth syndrome characterized by an excessive prenatal and postnatal growth, macrosomia, macroglossia, and hemihyperplasia. The molecular basis of this syndrome is complex and heterogeneous, involving genes located at 11p15.5. BWS is correlated with assisted reproductive techniques. BWS in individuals born following assisted reproductive techniques has been found to occur four to nine times higher compared to children with to BWS born after spontaneous conception. Here, we report a series of 187 patients with to BWS born either after assisted reproductive techniques or conceived naturally. Eighty-eight percent of BWS patients born via assisted reproductive techniques had hypomethylation of KCNQ1OT1:TSS-DMR in comparison with 49% for patients with BWS conceived naturally. None of the patients with BWS born via assisted reproductive techniques had hypermethylation of H19/IGF2:IG-DMR, neither CDKN1 C mutations nor patUPD11. We did not find differences in the frequency of multi-locus imprinting disturbances between groups. Patients with BWS born via assisted reproductive techniques had an increased frequency of advanced bone age, congenital heart disease, and decreased frequency of earlobe anomalies but these differences may be explained by the different molecular background compared to those with BWS and spontaneous fertilization. We conclude there is a correlation of the molecular etiology of BWS with the type of conception. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Time-Resolved Nucleic Acid Hybridization Beacons Utilizing Unimolecular and Toehold-Mediated Strand Displacement Designs.

    Science.gov (United States)

    Massey, Melissa; Ancona, Mario G; Medintz, Igor L; Algar, W Russ

    2015-12-01

    Nucleic acid hybridization probes are sought after for numerous assay and imaging applications. These probes are often limited by the properties of fluorescent dyes, prompting the development of new probes where dyes are paired with novel or nontraditional luminescent materials. Luminescent terbium complexes are an example of such a material, and these complexes offer several unique spectroscopic advantages. Here, we demonstrate two nonstem-loop designs for light-up nucleic acid hybridization beacons that utilize time-resolved Förster resonance energy transfer (TR-FRET) between a luminescent Lumi4-Tb cryptate (Tb) donor and a fluorescent reporter dye, where time-resolved emission from the dye provides an analytical signal. Both designs are based on probe oligonucleotides that are labeled at their opposite termini with Tb and a fluorescent reporter dye. In one design, a probe is partially blocked with a quencher dye-labeled oligonucleotide, and target hybridization is signaled through toehold-mediated strand displacement and loss of a competitive FRET pathway. In the other design, the intrinsic folding properties of an unblocked probe are utilized in combination with a temporal mechanism for signaling target hybridization. This temporal mechanism is based on a recently elucidated "sweet spot" for TR-FRET measurements and exploits distance control over FRET efficiencies to shift the Tb lifetime within or outside the time-gated detection window for measurements. Both the blocked and unblocked beacons offer nanomolar (femtomole) detection limits, response times on the order of minutes, multiplexing through the use of different reporter dyes, and detection in complex matrices such as serum and blood. The blocked beacons offer better mismatch selectivity, whereas the unblocked beacons are simpler in design. The temporal mechanism of signaling utilized with the unblocked beacons also plays a significant role with the blocked beacons and represents a new and effective

  8. Results from the northern New Mexico satellite-beacon radio interferometer

    International Nuclear Information System (INIS)

    Carlos, R.; Jacobson, A.; Massey, R.; Wu, G.

    1994-01-01

    An interferometer described in the Boston, 1992, meeting of the Beacon Satellite Symposium has been in full operation for over a year now. It consists of four autonomous stations; three are in a triangle 70 km on a side and one is in the center. The stations receive the VHF beacons from two geosynchronous satellites, GOES-2 and ATS-3. The phases of the beacons are tracked at each station by referring them to an extremely stable rubidium oscillator. The studies of the two satellites are virtually separate experiments. The received phase of the beacon is retarded by the increased Total-Electron-Content of the dense regions of waves in the ionosphere. By comparing the phase history at four spatially separated stations, the authors can determine the two-dimensional propagation vector of the waves. This array is optimal for wavelengths of 70--300 km (periods of 300--3,000 seconds). Since the measurement is of the phase of the signal rather than the difference between the O-mode and X-mode phases, and since the beacons are in the VHF rather than in the L-band of GPS beacons, the array is very sensitive. It has a noise level of 10 13 electrons/m 2 , or 10 -4 of the normal daytime TEC. This has been verified by operating two stations in the same location, so that they saw the same ionosphere. The first interesting results from a year's study is that the authors do not see the same TID's when looking at the two satellites. One conclusion they draw is that they do not see evidence of ionospheric winds

  9. Theoretical analysis and experimental study of constraint boundary conditions for acquiring the beacon in satellite-ground laser communications

    Science.gov (United States)

    Yu, Siyuan; Wu, Feng; Wang, Qiang; Tan, Liying; Ma, Jing

    2017-11-01

    Acquisition and recognition for the beacon is the core technology of establishing the satellite optical link. In order to acquire the beacon correctly, the beacon image should be recognized firstly, excluding the influence of the background light. In this processing, many factors will influence the recognition precision of the beacon. This paper studies the constraint boundary conditions for acquiring the beacon from the perspective of theory and experiment, and as satellite-ground laser communications, an approach for obtaining the adaptive segmentation method is also proposed. Finally, the long distance laser communication experiment (11.16 km) verifies the validity of this method and the tracking error with the method is the least compared with the traditional approaches. The method helps to greatly improve the tracking precision in the satellite-ground laser communications.

  10. Image analysis, methanogenic activity measurements, and molecular biological techniques to monitor granular sludge from EGSB reactors fed with oleic acid

    NARCIS (Netherlands)

    Pereira, M.A.; Roest, de K.; Stams, A.J.M.; Akkermans, A.D.L.; Amaral, A.L.; Pons, M.N.; Ferreira, E.C.; Mota, M.; Alves, M.

    2003-01-01

    Morphological changes in anaerobic granular sludge fed with increasing loads of oleic acid were quantified by image analysis. The combination of this technique with data on-the accumulation of adsorbed long chain fatty acid and with the molecular characterization of microbial community gave insight

  11. Fundamentals of quality assessment of molecular amplification methods in clinical diagnostics. International Federation of Clinical Chemistry Scientific Division Committee on Molecular Biology Techniques.

    Science.gov (United States)

    Neumaier, M; Braun, A; Wagener, C

    1998-01-01

    The increasing interest in molecular biology diagnostics is a result of the tremendous gain of scientific knowledge in genetics, made possible especially since the introduction of amplification techniques. High expectations have been placed on genetic testing, and the number of laboratories now using the relevant technology is rapidly increasing--resulting in an obvious need for standardization and definition of laboratory organization. This communication is an effort towards that end. We address aspects that should be considered when structuring a new molecular diagnostic laboratory, and we discuss individual preanalytical and analytical procedures, from sampling to evaluation of assay results. In addition, different means of controlling contamination are discussed. Because the methodology is in constant change, no general standards can be defined. Accordingly, this publication is intended to serve as a recommendation for good laboratory practice and internal quality control and as a guide to troubleshooting, primarily in amplification techniques.

  12. Identification of microorganisms involved in nitrogen removal from wastewater treatment systems by means of molecular biology techniques

    International Nuclear Information System (INIS)

    Figueroa, M.; Alonso-Gutierrez, J.; Campos, J. L.; Mendez, R.; Mosquera-Corral, A.

    2010-01-01

    The identification of the main bacteria populations present in the granular biomass from a biological reactor treating wastewater has been performed by applying two different molecular biology techniques. By means of the DGGE technique five different genera of heterotrophic bacteria (Thiothrix, Thauera, Cloroflexi, Comamonas y Zoogloea) and one of ammonia oxidizing bacteria (Nitrosomanas) were identified. The FISH technique, based on microscopy, allowed the in situ visualization and quantification of those microorganisms. Special attention was paid to filamentous bacteria distribution (Thiothrix and Cloroflexi) which could exert a structural function in aerobic granular sludge. (Author) 26 refs.

  13. Improvement of the inlet system for the spray-jet technique for use in spectroscopic studies and molecular deposition

    International Nuclear Information System (INIS)

    Yamada, Toshiki; Shinohara, Hidenori; Mashiko, Shinro

    2006-01-01

    We previously developed a molecular beam apparatus with a spray-jet technique in order to produce a molecular beam of non-volatile molecules in vacuum from the sprayed mist of a sample solution. The apparatus is for use in spectroscopic studies or a means of molecular deposition. The spray-jet inlet system consisted of an ultrasonic nebulizer, an inlet chamber and a pulsed nozzle. In the present paper, further improvements to the spray-jet inlet system are reported. The main improvement is the introduction of a pneumatic nebulizer to replace the previous ultrasonic nebulizer. The efficiency of molecular beam generation was evaluated on the basis of the signal intensity of the resonantly enhanced multiphoton ionization time-of-flight mass (REMPI-TOFMS) spectra for a Rhodamine B/methanol solution and the amount of sample consumed. The introduction of the pneumatic nebulizer increased the efficiency by a factor of 20

  14. Functional characterisation of metal(loid) processes in planta through the integration of synchrotron techniques and plant molecular biology.

    Science.gov (United States)

    Donner, Erica; Punshon, Tracy; Guerinot, Mary Lou; Lombi, Enzo

    2012-04-01

    Functional characterisation of the genes regulating metal(loid) homeostasis in plants is a major focus for phytoremediation, crop biofortification and food security research. Recent advances in X-ray focussing optics and fluorescence detection have greatly improved the potential to use synchrotron techniques in plant science research. With use of methods such as micro X-ray fluorescence mapping, micro computed tomography and micro X-ray absorption near edge spectroscopy, metal(loids) can be imaged in vivo in hydrated plant tissues at submicron resolution, and laterally resolved metal(loid) speciation can also be determined under physiologically relevant conditions. This article focuses on the benefits of combining molecular biology and synchrotron-based techniques. By using molecular techniques to probe the location of gene expression and protein production in combination with laterally resolved synchrotron techniques, one can effectively and efficiently assign functional information to specific genes. A review of the state of the art in this field is presented, together with examples as to how synchrotron-based methods can be combined with molecular techniques to facilitate functional characterisation of genes in planta. The article concludes with a summary of the technical challenges still remaining for synchrotron-based hard X-ray plant science research, particularly those relating to subcellular level research.

  15. Molecular Technique to Reduce PCR Bias for Deeper Understanding of Microbial Diversity

    Science.gov (United States)

    Vaishampayan, Parag A.; Venkateswaran, Kasthuri J.

    2012-01-01

    Current planetary protection policies require that spacecraft targeted to sensitive solar system bodies be assembled and readied for launch in controlled cleanroom environments. A better understanding of the distribution and frequency at which high-risk contaminant microbes are encountered on spacecraft surfaces would significantly aid in assessing the threat of forward contamination. However, despite a growing understanding of the diverse microbial populations present in cleanrooms, less abundant microbial populations are probably not adequately taken into account due to technological limitations. This novel approach encompasses a wide spectrum of microbial species and will represent the true picture of spacecraft cleanroom-associated microbial diversity. All of the current microbial diversity assessment techniques are based on an initial PCR amplification step. However, a number of factors are known to bias PCR amplification and jeopardize the true representation of bacterial diversity. PCR amplification of a minor template appears to be suppressed by the amplification of a more abundant template. It is widely acknowledged among environmental molecular microbiologists that genetic biosignatures identified from an environment only represent the most dominant populations. The technological bottleneck overlooks the presence of the less abundant minority population and may underestimate their role in the ecosystem maintenance. DNA intercalating agents such as propidium monoazide (PMA) covalently bind with DNA molecules upon photolysis using visible light, and make it unavailable for DNA polymerase enzyme during polymerase chain reaction (PCR). Environmental DNA samples will be treated with suboptimum PMA concentration, enough to intercalate with 90 99% of the total DNA. The probability of PMA binding with DNA from abundant bacterial species will be much higher than binding with DNA from less abundant species. This will increase the relative DNA concentration of

  16. Australian endemic pest tephritids: genetic, molecular and microbial tools for improved Sterile Insect Technique.

    Science.gov (United States)

    Raphael, Kathryn A; Shearman, Deborah C A; Gilchrist, A Stuart; Sved, John A; Morrow, Jennifer L; Sherwin, William B; Riegler, Markus; Frommer, Marianne

    2014-01-01

    Among Australian endemic tephritid fruit flies, the sibling species Bactrocera tryoni and Bactrocera neohumeralis have been serious horticultural pests since the introduction of horticulture in the nineteenth century. More recently, Bactrocera jarvisi has also been declared a pest in northern Australia. After several decades of genetic research there is now a range of classical and molecular genetic tools that can be used to develop improved Sterile Insect Technique (SIT) strains for control of these pests. Four-way crossing strategies have the potential to overcome the problem of inbreeding in mass-reared strains of B. tryoni. The ability to produce hybrids between B. tryoni and the other two species in the laboratory has proved useful for the development of genetically marked strains. The identification of Y-chromosome markers in B. jarvisi means that male and female embryos can be distinguished in any strain that carries a B. jarvisi Y chromosome. This has enabled the study of homologues of the sex-determination genes during development of B jarvisi and B. tryoni, which is necessary for the generation of genetic-sexing strains. Germ-line transformation has been established and a draft genome sequence for B. tryoni released. Transcriptomes from various species, tissues and developmental stages, to aid in identification of manipulation targets for improving SIT, have been assembled and are in the pipeline. Broad analyses of the microbiome have revealed a metagenome that is highly variable within and across species and defined by the environment. More specific analyses detected Wolbachia at low prevalence in the tropics but absent in temperate regions, suggesting a possible role for this endosymbiont in future control strategies.

  17. A comparative study of conventional and molecular techniques in diagnosis of campylobacter gastroenteritis in children.

    Science.gov (United States)

    Ghosh, Roumi; Uppal, Beena; Aggarwal, Prabhav; Chakravarti, Anita; Jha, Arun Kumar; Dubey, A P

    2014-01-01

    Campylobacter species are a significant cause of gastroenteritis among children worldwide. Conventional methods for detection of Campylobacter spp. based on cultural isolation and biochemical tests are cumbersome and time consuming. Because of their superior sensitivity and cost effectiveness, molecular methods are often used for identification of the pathogens. To evaluate different diagnostic methods for identification of Campylobacter. Faecal samples were collected from 585 children (age ≤ 12 years) with acute diarrhoea admitted in a tertiary-care hospital, excluding children already on antimicrobial therapy. All samples were examined by four methods: Grams' staining, culture methods, Enzyme-Immuno Assay, and Polymerase Chain Reaction (PCR). After Grams' staining, samples were inoculated on modified charcoal cefoperazone deoxycholate agar. ProSpecT™ Microplate Assay® and PCR assay using cadF gene was done for detection of Campylobacter specific antigen and DNA, respectively, in faecal samples. McNemar's test was used to compare the results wherever applicable. 197 cases (33.67%) were found to be positive for Campylobacter by at least one method. But only 121 (20.78%) out of the 585 stool specimens tested fulfilled the positivity criteria, i.e., positive either by culture or by any two tests among other three. Culture had very low sensitivity (37.19%), whereas PCR had the highest (96.69%) sensitivity but lowest positive predictive value (86.03%). Rapid Grams' staining technique (sensitivity 63.64%) was found to be better than culture. Detection by PCR and ELISA was significantly better than by culture on selective media and Grams' staining (pdetection rates of Campylobacter in children with diarrhoea. However, enzyme-immuno assay with high accuracy has the advantage of applicability in resource-poor settings.

  18. Geologic map of the Beacon Rock quadrangle, Skamania County, Washington

    Science.gov (United States)

    Evarts, Russell C.; Fleck, Robert J.

    2017-06-06

    The Beacon Rock 7.5′ quadrangle is located approximately 50 km east of Portland, Oregon, on the north side of the Columbia River Gorge, a scenic canyon carved through the axis of the Cascade Range by the Columbia River. Although approximately 75,000 people live within the gorge, much of the region remains little developed and is encompassed by the 292,500-acre Columbia River Gorge National Scenic Area, managed by a consortium of government agencies “to pro­tect and provide for the enhancement of the scenic, cultural, recreational and natural resources of the Gorge and to protect and support the economy of the Columbia River Gorge area.” As the only low-elevation corridor through the Cascade Range, the gorge is a critical regional transportation and utilities corridor (Wang and Chaker, 2004). Major state and national highways and rail lines run along both shores of the Columbia River, which also provides important water access to ports in the agricultural interior of the Pacific Northwest. Transmission lines carry power from hydroelectric facilities in the gorge and farther east to the growing urban areas of western Oregon and Washington, and natural-gas pipelines transect the corridor (Wang and Chaker, 2004). These lifelines are highly vulnerable to disruption by earthquakes, landslides, and floods. A major purpose of the work described here is to identify and map geologic hazards, such as faults and landslide-prone areas, to provide more accurate assessments of the risks associated with these features.The steep canyon walls of the map area reveal exten­sive outcrops of Miocene flood-basalt flows of the Columbia River Basalt Group capped by fluvial deposits of the ances­tral Columbia River, Pliocene lavas erupted from the axis of the Cascade arc to the east, and volcanic rocks erupted from numerous local vents. The Columbia River Basalt Group unconformably rests on a sequence of late Oligocene and early Miocene rocks of the ancestral Cascade volcanic arc

  19. The technologist's role in nuclear medicine in development of centellographic techniques, x-ray guides surgery and molecular techniques

    International Nuclear Information System (INIS)

    Alvarez, Bettina; Juri, Cecilia; Manrique, Gonzalo; Andruskevicius, Patricia; Canepa, Jorge; Coppe, Fatima; Cuervo, Aurora; Lopez, Andrea; Gonzalez, Mirta; Guissoli, Patricia; Rodriguez, Sergio

    2006-01-01

    In our center the Technician in Nuclear Medicine participates in the development and evaluation of Nuclear Medicine and Molecular Biology linked methodologies, with the strategy of the sentinel lymph node (SLN). The aim of the present work is to validate nuclear and molecular methods, using known clinical and prognostic illness parameters. We included prospectively 40 patients with clinically localized melanoma, with an average of 3.6 mm (status: 0.5-15.0 mm) Breslow thickness. The middle age of the patients was 54.2 years (status: 24-82 years), 25 females and 15 males. The tracer used was 99mTc labeled albumin nanocolloid, doing a lymphoscintigraphy 16-18 hours before the surgery, with a total dose of 111-185 MBq. Sequential images were acquired every 5 minutes in a gamma camera during an hour post injection or until drainage was visualized. Once a SLN was located, we did an orthogonal view to locate the nodals in the three-dimensional space. The nodal territories identified by means of lymphoscintigraphy were explored surgically employing an intraoperative gamma probe. Nodal and adjacent tissue radioactivity was measured in vivo and verified ex vivo after the resection. A relation of counts node/background bigger than 2 in vivo and bigger than 10 ex vivo was established in order to consider a node SLN. The SLNs were analyzed by means of histopathology and in 14 patients the expression was studied also using RT-PCR, employing TIR, MART-1 and MIA as markers, in a single-step protocol with 35 cycles of amplification. The experiments were done in duplicates and they included positive and negative control panels. SLN was identified in 38/39 surgical patients (97.4 %), each patient presenting an average of 1.3 nodal. Nodal metastasis were diagnosed by histopathology in 9 patients (24 %). A significant correlation was stated between the metastasis commitment of the SLN and the illness relapsing (p=0.019) during the follow up of 40.8 months (status: 6.7-94.6 months

  20. The Effects of a Rectangular Rapid-Flashing Beacon on Vehicle Speed

    Science.gov (United States)

    VanWagner, Michelle; Van Houten, Ron; Betts, Brian

    2011-01-01

    In 2008, nearly 31% of vehicle fatalities were related to failure to adhere to safe vehicle speeds (National Highway Traffic Safety Administration [NHTSA], 2009). The current study evaluated the effect of a rectangular rapid-flashing beacon (RRFB) triggered by excessive speed on vehicle speed using a combined alternating treatments and reversal…

  1. A Beacon Transmission Power Control Algorithm Based on Wireless Channel Load Forecasting in VANETs.

    Science.gov (United States)

    Mo, Yuanfu; Yu, Dexin; Song, Jun; Zheng, Kun; Guo, Yajuan

    2015-01-01

    In a vehicular ad hoc network (VANET), the periodic exchange of single-hop status information broadcasts (beacon frames) produces channel loading, which causes channel congestion and induces information conflict problems. To guarantee fairness in beacon transmissions from each node and maximum network connectivity, adjustment of the beacon transmission power is an effective method for reducing and preventing channel congestion. In this study, the primary factors that influence wireless channel loading are selected to construct the KF-BCLF, which is a channel load forecasting algorithm based on a recursive Kalman filter and employs multiple regression equation. By pre-adjusting the transmission power based on the forecasted channel load, the channel load was kept within a predefined range; therefore, channel congestion was prevented. Based on this method, the CLF-BTPC, which is a transmission power control algorithm, is proposed. To verify KF-BCLF algorithm, a traffic survey method that involved the collection of floating car data along a major traffic road in Changchun City is employed. By comparing this forecast with the measured channel loads, the proposed KF-BCLF algorithm was proven to be effective. In addition, the CLF-BTPC algorithm is verified by simulating a section of eight-lane highway and a signal-controlled urban intersection. The results of the two verification process indicate that this distributed CLF-BTPC algorithm can effectively control channel load, prevent channel congestion, and enhance the stability and robustness of wireless beacon transmission in a vehicular network.

  2. A Beacon Transmission Power Control Algorithm Based on Wireless Channel Load Forecasting in VANETs.

    Directory of Open Access Journals (Sweden)

    Yuanfu Mo

    Full Text Available In a vehicular ad hoc network (VANET, the periodic exchange of single-hop status information broadcasts (beacon frames produces channel loading, which causes channel congestion and induces information conflict problems. To guarantee fairness in beacon transmissions from each node and maximum network connectivity, adjustment of the beacon transmission power is an effective method for reducing and preventing channel congestion. In this study, the primary factors that influence wireless channel loading are selected to construct the KF-BCLF, which is a channel load forecasting algorithm based on a recursive Kalman filter and employs multiple regression equation. By pre-adjusting the transmission power based on the forecasted channel load, the channel load was kept within a predefined range; therefore, channel congestion was prevented. Based on this method, the CLF-BTPC, which is a transmission power control algorithm, is proposed. To verify KF-BCLF algorithm, a traffic survey method that involved the collection of floating car data along a major traffic road in Changchun City is employed. By comparing this forecast with the measured channel loads, the proposed KF-BCLF algorithm was proven to be effective. In addition, the CLF-BTPC algorithm is verified by simulating a section of eight-lane highway and a signal-controlled urban intersection. The results of the two verification process indicate that this distributed CLF-BTPC algorithm can effectively control channel load, prevent channel congestion, and enhance the stability and robustness of wireless beacon transmission in a vehicular network.

  3. Scheduled MAC in Beacon Overlay Networks for Underwater Localization and Time-Synchronization

    NARCIS (Netherlands)

    van Kleunen, W.A.P.; Meratnia, Nirvana; Havinga, Paul J.M.

    2011-01-01

    In this article we introduce a MAC protocol designed for underwater localization and time-synchronisation. The MAC protocol assumes a network of static reference nodes and allows blind nodes to be localized by listening-only to the beacon messages. Such a system is known to be very scalable. We show

  4. The Roles of Beaconing and Dead Reckoning in Human Virtual Navigation

    Science.gov (United States)

    Bodily, Kent D.; Daniel, Thomas A.; Sturz, Bradley R.

    2012-01-01

    Beaconing is a process in which the distance between a visual landmark and current position is reduced in order to return to a location. In contrast, dead reckoning is a process in which vestibular, kinesthetic and/or optic flow cues are utilized to update speed of movement, elapsed time of movement, and direction of movement to return to a…

  5. Impacts of Fog Characteristics, Forward Illumination, and Warning Beacon Intensity Distribution on Roadway Hazard Visibility

    Directory of Open Access Journals (Sweden)

    John D. Bullough

    2016-01-01

    Full Text Available Warning beacons are critical for the safety of transportation, construction, and utility workers. These devices need to produce sufficient luminous intensity to be visible without creating glare to drivers. Published standards for the photometric performance of warning beacons do not address their performance in conditions of reduced visibility such as fog. Under such conditions light emitted in directions other than toward approaching drivers can create scattered light that makes workers and other hazards less visible. Simulations of visibility of hazards under varying conditions of fog density, forward vehicle lighting, warning beacon luminous intensity, and intensity distribution were performed to assess their impacts on visual performance by drivers. Each of these factors can influence the ability of drivers to detect and identify workers and hazards along the roadway in work zones. Based on the results, it would be reasonable to specify maximum limits on the luminous intensity of warning beacons in directions that are unlikely to be seen by drivers along the roadway, limits which are not included in published performance specifications.

  6. Beacon-Based Service Publishing Framework in Multiservice Wi-Fi Hotspots

    Directory of Open Access Journals (Sweden)

    Di Sorte Dario

    2007-01-01

    Full Text Available In an expected future multiaccess and multiservice IEEE 802.11 environment, the problem of providing users with useful service-related information to support a correct rapid network selection is expected to become a very important issue. A feasible short-term 802.11-tailored working solution, compliant with existing equipment, is to publish service information encoded within the SSID information element within beacon frames. This makes it possible for an operator to implement service publishing in 802.11 networks while waiting for a standardized mechanism. Also, this straightforward approach has allowed us to evaluate experimentally the performance of a beacon-based service publishing solution. In fact, the main focus of the paper is indeed to present a quantitative comparison of service discovery times between the legacy scenario, where the user is forced to associate and authenticate with a network point of access to check its service offer, and the enhanced scenario where the set of service-related information is broadcasted within beacons. These discovery times are obtained by processing the results of a measurement campaign performed in a multiaccess/service 802.11 environment. This analysis confirms the effectiveness of the beacon-based approach. We also show that the cost in terms of wireless bandwidth consumption of such solution is low.

  7. Analysis and Enhancement of IEEE 802.15.4e DSME Beacon Scheduling Model

    Directory of Open Access Journals (Sweden)

    Kwang-il Hwang

    2014-01-01

    Full Text Available In order to construct a successful Internet of things (IoT, reliable network construction and maintenance in a sensor domain should be supported. However, IEEE 802.15.4, which is the most representative wireless standard for IoT, still has problems in constructing a large-scale sensor network, such as beacon collision. To overcome some problems in IEEE 802.15.4, the 15.4e task group proposed various different modes of operation. Particularly, the IEEE 802.15.4e deterministic and synchronous multichannel extension (DSME mode presents a novel scheduling model to solve beacon collision problems. However, the DSME model specified in the 15.4e draft does not present a concrete design model but a conceptual abstract model. Therefore, in this paper we introduce a DSME beacon scheduling model and present a concrete design model. Furthermore, validity and performance of DSME are evaluated through experiments. Based on experiment results, we analyze the problems and limitations of DSME, present solutions step by step, and finally propose an enhanced DSME beacon scheduling model. Through additional experiments, we prove the performance superiority of enhanced DSME.

  8. Supplementary Material for: BEACON: automated tool for Bacterial GEnome Annotation ComparisON

    KAUST Repository

    Kalkatawi, Manal M.

    2015-01-01

    Abstract Background Genome annotation is one way of summarizing the existing knowledge about genomic characteristics of an organism. There has been an increased interest during the last several decades in computer-based structural and functional genome annotation. Many methods for this purpose have been developed for eukaryotes and prokaryotes. Our study focuses on comparison of functional annotations of prokaryotic genomes. To the best of our knowledge there is no fully automated system for detailed comparison of functional genome annotations generated by different annotation methods (AMs). Results The presence of many AMs and development of new ones introduce needs to: a/ compare different annotations for a single genome, and b/ generate annotation by combining individual ones. To address these issues we developed an Automated Tool for Bacterial GEnome Annotation ComparisON (BEACON) that benefits both AM developers and annotation analysers. BEACON provides detailed comparison of gene function annotations of prokaryotic genomes obtained by different AMs and generates extended annotations through combination of individual ones. For the illustration of BEACONâ s utility, we provide a comparison analysis of multiple different annotations generated for four genomes and show on these examples that the extended annotation can increase the number of genes annotated by putative functions up to 27 %, while the number of genes without any function assignment is reduced. Conclusions We developed BEACON, a fast tool for an automated and a systematic comparison of different annotations of single genomes. The extended annotation assigns putative functions to many genes with unknown functions. BEACON is available under GNU General Public License version 3.0 and is accessible at: http://www.cbrc.kaust.edu.sa/BEACON/ .

  9. Recent research in flaxseed (oil seed) on molecular structure and metabolic characteristics of protein, heat processing-induced effect and nutrition with advanced synchrotron-based molecular techniques.

    Science.gov (United States)

    Doiron, Kevin J; Yu, Peiqiang

    2017-01-02

    Advanced synchrotron radiation-based infrared microspectroscopy is able to reveal feed and food structure feature at cellular and molecular levels and simultaneously provides composition, structure, environment, and chemistry within intact tissue. However, to date, this advanced synchrotron-based technique is still seldom known to food and feed scientists. This article aims to provide detailed background for flaxseed (oil seed) protein research and then review recent progress and development in flaxseed research in ruminant nutrition in the areas of (1) dietary inclusion of flaxseed in rations; (2) heat processing effect; (3) assessing dietary protein; (4) synchrotron-based Fourier transform infrared microspectroscopy as a tool of nutritive evaluation within cellular and subcellular dimensions; (5) recent synchrotron applications in flaxseed research on a molecular basis. The information described in this paper gives better insight in flaxseed research progress and update.

  10. Image analysis, methanogenic activity measurements, and molecular biological techniques to monitor granular sludge from EGSB reactors fed with oleic acid

    OpenAIRE

    Pereira, M.A.; Roest, de, K.; Stams, A.J.M.; Akkermans, A.D.L.; Amaral, A.L.; Pons, M.N.; Ferreira, E.C.; Mota, M.; Alves, M.

    2003-01-01

    Morphological changes in anaerobic granular sludge fed with increasing loads of oleic acid were quantified by image analysis. The combination of this technique with data on-the accumulation of adsorbed long chain fatty acid and with the molecular characterization of microbial community gave insight into the mechanisms of sludge disintegration, flotation and washoutMorphological changes in anaerobic granular sludge fed with increasing loads of oleic acid were quantified by image analysis. The ...

  11. Techniques and instruments used for real-time analysis of atmospheric nanoscale molecular clusters: A review

    Directory of Open Access Journals (Sweden)

    Xue Li

    2015-11-01

    Full Text Available The extremely high concentrations of PM2.5 (particulate matter with an aerodynamic meter ≤ 2.5 μm during severe and persistent haze events in China have been closely related to the formation of secondary aerosols (SA. New particle formation (NPF is the critical initial step of SA formation. New particles are commonly formed from gas-phase precursors (e.g., SO2, volatile organic compounds via nucleation and initial growth, in which molecular clusters with a mobility diameter smaller than 3 nm (hereafter referred to nanoscale molecular clusters will be involved throughout the whole process. Recently, significant breakthroughs have been obtained on NPF studies, which are mostly attributed to the technical development in the real-time analysis of size-resolved number concentration and chemical composition of nanoscale molecular clusters. Regarding the detection of size-resolved number concentrations of nanoscale molecular clusters, both methods and instruments have been well built up; practical application in laboratory-scale experiments and field measurements have also been successfully demonstrated. In contrast, real-time analysis of chemical composition of nanoscale molecular clusters has still encountered the great challenges caused by the complex organic compositions of the clusters, and improvement of present analytical strategies is urgently required. The better understanding in NPF will not only benefit the atmospheric modeling and climate predictions but also the source control of SA.

  12. Detection of microbial diversity in endocarditis using cultivation-independent molecular techniques

    DEFF Research Database (Denmark)

    Wolff, Tine Y; Moser, Claus Ernst; Bundgaard, Henning

    2011-01-01

    Background: The aim of this study was to investigate whether the diagnosis of infective endocarditis (IE) could be improved using molecular tools in addition to standard microscopy and cultivation methods. Methods: Cultivation was performed on blood or tissue samples as recommended in the modified...... and all were monomicrobial. Molecular methods showed the presence of DNA from multiple bacterial species in 6 of the samples and indicated a larger variety of bacteria in the different samples than identified by cultivation. For 8 of the patients there was a good correlation between the results...

  13. Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy: An analytical technique to understand therapeutic responses at the molecular level.

    Science.gov (United States)

    Kalmodia, Sushma; Parameswaran, Sowmya; Yang, Wenrong; Barrow, Colin J; Krishnakumar, Subramanian

    2015-11-16

    Rapid monitoring of the response to treatment in cancer patients is essential to predict the outcome of the therapeutic regimen early in the course of the treatment. The conventional methods are laborious, time-consuming, subjective and lack the ability to study different biomolecules and their interactions, simultaneously. Since; mechanisms of cancer and its response to therapy is dependent on molecular interactions and not on single biomolecules, an assay capable of studying molecular interactions as a whole, is preferred. Fourier Transform Infrared (FTIR) spectroscopy has become a popular technique in the field of cancer therapy with an ability to elucidate molecular interactions. The aim of this study, was to explore the utility of the FTIR technique along with multivariate analysis to understand whether the method has the resolution to identify the differences in the mechanism of therapeutic response. Towards achieving the aim, we utilized the mouse xenograft model of retinoblastoma and nanoparticle mediated targeted therapy. The results indicate that the mechanism underlying the response differed between the treated and untreated group which can be elucidated by unique spectral signatures generated by each group. The study establishes the efficiency of non-invasive, label-free and rapid FTIR method in assessing the interactions of nanoparticles with cellular macromolecules towards monitoring the response to cancer therapeutics.

  14. Evaluation of molecular typing techniques to assign genetic diversity among Saccharomyces cerevisiae strains

    NARCIS (Netherlands)

    Baleiras Couto, M.M.; Eijsma, B.; Hofstra, H.; Huis in 't Veld, J.H.J.; Vossen, J.M.B.M. van der

    1996-01-01

    Discrimination of strains within the species Saccharomyces cerevisiae was demonstrated by the use of four different techniques to type 15 strains isolated from spoiled wine and beer. Random amplified polymorphic DNA with specific oligonucleotides and PCR fingerprinting with the microsatellite

  15. The molecular imaging approach to image infections and inflammation by nuclear medicine techniques

    NARCIS (Netherlands)

    Signore, Alberto; Glaudemans, Andor W. J. M.

    2011-01-01

    Inflammatory and infectious diseases are a heterogeneous class of diseases that may be divided into infections, acute inflammation and chronic inflammation. Radiological imaging techniques have, with the exception of functional MRI, high sensitivity but lack in specificity. Nuclear medicine

  16. Exploring Surface Analysis Techniques for the Detection of Molecular Contaminants on Spacecraft

    Science.gov (United States)

    Rutherford, Gugu N.; Seasly, Elaine; Thornblom, Mark; Baughman, James

    2016-01-01

    Molecular contamination is a known area of concern for spacecraft. To mitigate this risk, projects involving space flight hardware set requirements in a contamination control plan that establishes an allocation budget for the exposure of non-volatile residues (NVR) onto critical surfaces. The purpose of this work will focus on non-contact surface analysis and in situ monitoring to mitigate molecular contamination on space flight hardware. By using Scanning Electron Microscopy and Energy Dispersive Spectroscopy (SEM-EDS) with Raman Spectroscopy, an unlikely contaminant was identified on space flight hardware. Using traditional and surface analysis methods provided the broader view of the contamination sources allowing for best fit solutions to prevent any future exposure.

  17. Accuracy of molecular biology techniques for the diagnosis of Strongyloides stercoralis infection-A systematic review and meta-analysis.

    Science.gov (United States)

    Buonfrate, Dora; Requena-Mendez, Ana; Angheben, Andrea; Cinquini, Michela; Cruciani, Mario; Fittipaldo, Andrea; Giorli, Giovanni; Gobbi, Federico; Piubelli, Chiara; Bisoffi, Zeno

    2018-02-01

    Strongyloides stercoralis infection is a neglected tropical disease which can lead to severe symptoms and even death in immunosuppressed people. Unfortunately, its diagnosis is hampered by the lack of a gold standard, as the sensitivity of traditional parasitological tests (including microscopic examination of stool samples and coproculture) is low. Hence, alternative diagnostic methods, such as molecular biology techniques (mostly polymerase chain reaction, PCR) have been implemented. However, there are discrepancies in the reported accuracy of PCR. A systematic review with meta-analysis was conducted in order to evaluate the accuracy of PCR for the diagnosis of S. stercoralis infection. The protocol was registered with PROSPERO International Prospective Register of Systematic Reviews (record: CRD42016054298). Fourteen studies, 12 of which evaluating real-time PCR, were included in the analysis. The specificity of the techniques resulted high (ranging from 93 to 95%, according to the reference test(s) used). When all molecular techniques were compared to parasitological methods, the sensitivity of PCR was assessed at 71.8% (95% CI 52.2-85.5), that decreased to 61.8% (95% CI 42.0-78.4) when serology was added among the reference tests. Similarly, sensitivity of real-time PCR resulted 64.4% (95% CI 46.2-77.7) when compared to parasitological methods only, 56.5% (95% CI 39.2-72.4) including serology. PCR might not be suitable for screening purpose, whereas it might have a role as a confirmatory test.

  18. Comparison of the detection of periodontal pathogens in bacteraemia after tooth brushing by culture and molecular techniques.

    Science.gov (United States)

    Marín, M-J; Figuero, E; González, I; O'Connor, A; Diz, P; Álvarez, M; Herrera, D; Sanz, M

    2016-05-01

    The prevalence and amounts of periodontal pathogens detected in bacteraemia samples after tooth brushing-induced by means of four diagnostic technique, three based on culture and one in a molecular-based technique, have been compared in this study. Blood samples were collected from thirty-six subjects with different periodontal status (17 were healthy, 10 with gingivitis and 9 with periodontitis) at baseline and 2 minutes after tooth brushing. Each sample was analyzed by three culture-based methods [direct anaerobic culturing (DAC), hemo-culture (BACTEC), and lysis-centrifugation (LC)] and one molecular-based technique [quantitative polymerase chain reaction (qPCR)]. With culture any bacterial isolate was detected and quantified, while with qPCR only Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans were detected and quantified. Descriptive analyses, ANOVA and Chi-squared tests, were performed. Neither BACTEC nor qPCR detected any type of bacteria in the blood samples. Only LC (2.7%) and DAC (8.3%) detected bacteraemia, although not in the same patients. Fusobacterium nucleatum was the most frequently detected bacterial species. The disparity in the results when the same samples were analyzed with four different microbiological detection methods highlights the need for a proper validation of the methodology to detect periodontal pathogens in bacteraemia samples, mainly when the presence of periodontal pathogens in blood samples after tooth brushing was very seldom.

  19. Comparison of the detection of periodontal pathogens in bacteraemia after tooth brushing by culture and molecular techniques

    Science.gov (United States)

    Figuero, Elena; González, Itziar; O´Connor, Ana; Diz, Pedro; Álvarez, Maximiliano; Herrera, David; Sanz, Mariano

    2016-01-01

    Background The prevalence and amounts of periodontal pathogens detected in bacteraemia samples after tooth brushing-induced by means of four diagnostic technique, three based on culture and one in a molecular-based technique, have been compared in this study. Material and Methods Blood samples were collected from thirty-six subjects with different periodontal status (17 were healthy, 10 with gingivitis and 9 with periodontitis) at baseline and 2 minutes after tooth brushing. Each sample was analyzed by three culture-based methods [direct anaerobic culturing (DAC), hemo-culture (BACTEC), and lysis-centrifugation (LC)] and one molecular-based technique [quantitative polymerase chain reaction (qPCR)]. With culture any bacterial isolate was detected and quantified, while with qPCR only Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans were detected and quantified. Descriptive analyses, ANOVA and Chi-squared tests, were performed. Results Neither BACTEC nor qPCR detected any type of bacteria in the blood samples. Only LC (2.7%) and DAC (8.3%) detected bacteraemia, although not in the same patients. Fusobacterium nucleatum was the most frequently detected bacterial species. Conclusions The disparity in the results when the same samples were analyzed with four different microbiological detection methods highlights the need for a proper validation of the methodology to detect periodontal pathogens in bacteraemia samples, mainly when the presence of periodontal pathogens in blood samples after tooth brushing was very seldom. Key words:Bacteraemia, periodontitis, culture, PCR, tooth brushing. PMID:26946197

  20. Molecular Techniques for the Detection and Differentiation of Host and Parasitoid Species and the Implications for Fruit Fly Management.

    Science.gov (United States)

    Jenkins, Cheryl; Chapman, Toni A; Micallef, Jessica L; Reynolds, Olivia L

    2012-08-14

    Parasitoid detection and identification is a necessary step in the development and implementation of fruit fly biological control strategies employing parasitoid augmentive release. In recent years, DNA-based methods have been used to identify natural enemies of pest species where morphological differentiation is problematic. Molecular techniques also offer a considerable advantage over traditional morphological methods of fruit fly and parasitoid discrimination as well as within-host parasitoid identification, which currently relies on dissection of immature parasitoids from the host, or lengthy and labour-intensive rearing methods. Here we review recent research focusing on the use of molecular strategies for fruit fly and parasitoid detection and differentiation and discuss the implications of these studies on fruit fly management.

  1. Design of a K/Q-Band Beacon Receiver for the Alphasat TDP#5 Experiment

    Science.gov (United States)

    Morse, Jacquelynne R.

    2014-01-01

    This paper describes the design and performance of a coherent KQ-band (2040 GHz) beacon receiver developed at NASA Glenn Research Center (GRC) that will be installed at the Politecnico di Milano (POLIMI) for use in the Alphasat Technology Demonstration Payload 5 (TDP5) beacon experiment. The goal of this experiment is to characterize rain fade attenuation at 40 GHz to improve the performance of existing statistical rain attenuation models in the Q-band. The ground terminal developed by NASA GRC utilizes an FFT-based frequency estimation receiver capable of characterizing total path attenuation effects due to gaseous absorption, clouds, rain, and scintillation. The receiver system has been characterized in the lab and demonstrates a system dynamic range performance of better than 58 dB at 1 Hz and better than 48 dB at 10 Hz rates.

  2. Multi-Band Multi-Tone Tunable Millimeter-Wave Frequency Synthesizer For Satellite Beacon Transmitter

    Science.gov (United States)

    Simons, Rainee N.; Wintucky, Edwin G.

    2016-01-01

    This paper presents the design and test results of a multi-band multi-tone tunable millimeter-wave frequency synthesizer, based on a solid-state frequency comb generator. The intended application of the synthesizer is in a satellite beacon transmitter for radio wave propagation studies at K-band (18 to 26.5 GHz), Q-band (37 to 42 GHz), and E-band (71 to 76 GHz). In addition, the architecture for a compact beacon transmitter, which includes the multi-tone synthesizer, polarizer, horn antenna, and power/control electronics, has been investigated for a notional space-to-ground radio wave propagation experiment payload on a small satellite. The above studies would enable the design of robust high throughput multi-Gbps data rate future space-to-ground satellite communication links.

  3. Creation of a Library Tour Application for Mobile Equipment using iBeacon Technology

    Directory of Open Access Journals (Sweden)

    Jonathan Bradley

    2016-04-01

    Full Text Available We describe the design, development, and deployment of a library tour application utilizing Bluetooth Low Energy devices know as iBeacons. The tour application will serve as library orientation for incoming students. The students visit stations in the library with mobile equipment running a special tour app. When the app detects a beacon nearby, it automatically plays a video that describes the current location. After the tour, students are assessed according to the defined learning objectives. Special attention is given to issues encountered during development, deployment, content creation, and testing of this application that depend on functioning hardware, and the necessity of appointing a project manager to limit scope, define priorities, and create an actionable plan for the experiment.

  4. Nanosecond-level time synchronization of AERA using a beacon reference transmitter and commercial airplanes

    Science.gov (United States)

    Huege, Tim

    2017-03-01

    Radio detection of cosmic-ray air showers requires time synchronization of detectors on a nanosecond level, especially for advanced reconstruction algorithms based on the wavefront curvature and for interferometric analysis approaches. At the Auger Engineering Radio Array, the distributed, autonomous detector stations are time-synchronized via the Global Positioning System which, however, does not provide sufficient timing accuracy. We thus employ a dedicated beacon reference transmitter to correct for eventby-event clock drifts in our offline data analysis. In an independent cross-check of this "beacon correction" using radio pulses emitted by commercial airplanes, we have shown that the combined timing accuracy of the two methods is better than 2 nanoseconds.

  5. Nanosecond-level time synchronization of AERA using a beacon reference transmitter and commercial airplanes

    Directory of Open Access Journals (Sweden)

    Huege Tim

    2017-01-01

    Full Text Available Radio detection of cosmic-ray air showers requires time synchronization of detectors on a nanosecond level, especially for advanced reconstruction algorithms based on the wavefront curvature and for interferometric analysis approaches. At the Auger Engineering Radio Array, the distributed, autonomous detector stations are time-synchronized via the Global Positioning System which, however, does not provide sufficient timing accuracy. We thus employ a dedicated beacon reference transmitter to correct for eventby-event clock drifts in our offline data analysis. In an independent cross-check of this “beacon correction” using radio pulses emitted by commercial airplanes, we have shown that the combined timing accuracy of the two methods is better than 2 nanoseconds.

  6. Beaconing Performance in IEEE 802.11p Vehicular Networks: the Effect of Radio Channel Congestion

    OpenAIRE

    Librino, Francesco; Renda, Maria Elena; Santi, Paolo

    2013-01-01

    In this paper, we study the performance of the beaconing mechanism underlying active safety vehicular applications in presence of different levels of channel congestion. The importance of this study lies in the fact that channel congestion is considered a major factor influencing communication performance in vehicular networks, and that ours is the first investigation of the effects of congestion based on extensive, real-world measurements. The results of our study reveal that congestion has ...

  7. Time-Synchronized Beacons for Relative UAV Position Determination

    Data.gov (United States)

    National Aeronautics and Space Administration — Research is required to determine the optimal pulse length, pulse frequency, pulse power, and optical communications encoding technique to meet FAA and STMD...

  8. Fabrication of nanoscale gaps using a combination of self-assembled molecular and electron beam lithographic techniques

    International Nuclear Information System (INIS)

    Negishi, R.; Hasegawa, T.; Terabe, K.; Aono, M.; Ebihara, T.; Tanaka, H.; Ogawa, T.

    2006-01-01

    We have developed and tested a new method of fabricating nanogaps using a combination of self-assembled molecular and electron beam lithographic techniques. The method enables us to control the gap size with an accuracy of approximately 2 nm and designate the positions where the nanogaps should be formed with high-resolution patterning by using electron beam lithography. We have demonstrated the utility of the fabricated nanogaps by measuring a single electron tunneling phenomenon through dodecanethiol-coated Au nanoparticles placed in the fabricated nanogap

  9. Beacon: A three-dimensional structural analysis code for bowing history of fast breeder reactor cores

    International Nuclear Information System (INIS)

    Miki, K.

    1979-01-01

    The core elements of an LMFBR are bowed due to radial gradients of both temperature and neutron flux in the core. Since all hexagonal elements are multiply supported by adjacent elements or the restraint system, restraint forces and bending stresses are induced. In turn, these forces and stresses are relaxed by irradiation enhanced creep of the material. The analysis of the core bowing behavior requires a three-dimensional consideration of the mechanical interactions among the core elements, because the core consists of different kinds of elements and of fuel assemblies with various burnup histories. A new computational code BEACON has been developed for analyzing the bowing behavior of an LMFBR's core in three dimensions. To evaluate mechanical interactions among core elements, the code uses the analytical method of the earlier SHADOW code. BEACON analyzes the mechanical interactions in three directions, which form angles of 60 0 with one another. BEACON is applied to the 60 0 sector of a typical LMFBR's core for analyzing the bowing history during one equilibrium cycle. 120 core elements are treated, assuming the boundary condition of rotational symmetry. The application confirms that the code can be an effective tool for parametric studies as well as for detailed structural analysis of LMFBR's core. (orig.)

  10. Sparse Localization with a Mobile Beacon Based on LU Decomposition in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Chunhui Zhao

    2015-09-01

    Full Text Available Node localization is the core in wireless sensor network. It can be solved by powerful beacons, which are equipped with global positioning system devices to know their location information. In this article, we present a novel sparse localization approach with a mobile beacon based on LU decomposition. Our scheme firstly translates node localization problem into a 1-sparse vector recovery problem by establishing sparse localization model. Then, LU decomposition pre-processing is adopted to solve the problem that measurement matrix does not meet the re¬stricted isometry property. Later, the 1-sparse vector can be exactly recovered by compressive sensing. Finally, as the 1-sparse vector is approximate sparse, weighted Cen¬troid scheme is introduced to accurately locate the node. Simulation and analysis show that our scheme has better localization performance and lower requirement for the mobile beacon than MAP+GC, MAP-M, and MAP-MN schemes. In addition, the obstacles and DOI have little effect on the novel scheme, and it has great localization performance under low SNR, thus, the scheme proposed is robust.

  11. A Microfluidic Love-Wave Biosensing Device for PSA Detection Based on an Aptamer Beacon Probe.

    Science.gov (United States)

    Zhang, Feng; Li, Shuangming; Cao, Kang; Wang, Pengjuan; Su, Yan; Zhu, Xinhua; Wan, Ying

    2015-06-11

    A label-free and selective aptamer beacon-based Love-wave biosensing device was developed for prostate specific antigen (PSA) detection. The device consists of the following parts: LiTaO3 substrate with SiO2 film as wave guide layer, two set of inter-digital transducers (IDT), gold film for immobilization of the biorecongniton layer and a polydimethylsiloxane (PDMS) microfluidic channels. DNA aptamer, or "artificial antibody", was used as the specific biorecognition probe for PSA capture. Some nucleotides were added to the 3'-end of the aptamer to form a duplex with the 3'-end, turning the aptamer into an aptamer-beacon. Taking advantage of the selective target-induced assembly changes arising from the "aptamer beacon", highly selective and specific detection of PSA was achieved. Furthermore, PDMS microfluidic channels were designed and fabricated to realize automated quantitative sample injection. After optimization of the experimental conditions, the established device showed good performance for PSA detection between 10 ng/mL to 1 μg/mL, with a detection limit of 10 ng/mL. The proposed sensor might be a promising alternative for point of care diagnostics.

  12. Recent advances in molecular techniques to study microbial communities in food-associated matrices and processes

    NARCIS (Netherlands)

    Justé, A.; Thomma, B.P.H.J.; Lievens, B.

    2008-01-01

    In the last two decades major changes have occurred in how microbial ecologists study microbial communities. Limitations associated with traditional culture-based methods have pushed for the development of culture-independent techniques, which are primarily based on the analysis of nucleic acids.

  13. Growth of CdTe on Si(100) surface by ionized cluster beam technique: Experimental and molecular dynamics simulation

    Energy Technology Data Exchange (ETDEWEB)

    Araghi, Houshang, E-mail: araghi@aut.ac.ir [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Zabihi, Zabiholah [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Nayebi, Payman [Department of Physics, College of Technical and Engineering, Saveh Branch, Islamic Azad University, Saveh (Iran, Islamic Republic of); Ehsani, Mohammad Mahdi [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2016-10-15

    II–VI semiconductor CdTe was grown on the Si(100) substrate surface by the ionized cluster beam (ICB) technique. In the ICB method, when vapors of solid materials such as CdTe were ejected through a nozzle of a heated crucible into a vacuum region, nanoclusters were created by an adiabatic expansion phenomenon. The clusters thus obtained were partially ionized by electron bombardment and then accelerated onto the silicon substrate at 473 K by high potentials. The cluster size was determined using a retarding field energy analyzer. The results of X-ray diffraction measurements indicate the cubic zinc blende (ZB) crystalline structure of the CdTe thin film on the silicon substrate. The CdTe thin film prepared by the ICB method had high crystalline quality. The microscopic processes involved in the ICB deposition technique, such as impact and coalescence processes, have been studied in detail by molecular dynamics (MD) simulation.

  14. In vitro DNA binding studies of lenalidomide using spectroscopic in combination with molecular docking techniques

    Science.gov (United States)

    Xu, Liang; Hu, Yan-Xi; Li, Yan-Cheng; Zhang, Li; Ai, Hai-Xin; Liu, Yu-Feng; Liu, Hong-Sheng

    2018-02-01

    In the present work, the binding interaction between lenalidomide (LEN) and calf thymus DNA (ct-DNA) was systematically studied by using fluorescence, ultraviolet-visible (UV-vis) absorption, circular dichroism (CD) spectroscopies under imitated physiological conditions (pH = 7.4) coupled with molecular docking. It was found that LEN was bound to ct-DNA with high binding affinity (Ka = 2.308 × 105 M-1 at 283 K) through groove binding as evidenced by a slight decrease in the absorption intensity in combination with CD spectra. Thermodynamic parameters (ΔG 0 and ΔS interaction. Furthermore, competitive binding experiments with ethidium bromide and 4‧, 6-dia-midino-2-phenylindoleas probes showed that LEN could preferentially bind in the minor groove of double-stranded DNA. The average lifetime of LEN was calculated to be 7.645 ns. The φ of LEN was measured as 0.09 and non-radiation energy transfer between LEN and DNA had occurred. The results of the molecular docking were consistent with the experimental results. This study explored the potential applicability of the spectroscopic properties of LEN and also investigated its interactions with relevant biological targets. In addition, it will provide some theoretical references for the deep research of simultaneous administration of LEN with other drugs.

  15. Molecular diagnosis of fragile X syndrome using methylation sensitive techniques in a cohort of patients with intellectual disability.

    Science.gov (United States)

    Chaudhary, Adeel G; Hussein, Ibtessam R; Abuzenadah, Adel; Gari, Mamdouh; Bassiouni, Randa; Sogaty, Samira; Lary, Sahira; Al-Quaiti, Maha; Al Balwi, Mohammed; Al Qahtani, Mohammed

    2014-04-01

    Fragile X syndrome, the most common form of inherited intellectual disability, is caused by expansion of CGG trinucleotide repeat at the 5' untranslated region of the FMR1 gene at Xq27. In affected individuals, the CGG repeat expansion leads to hypermethylation and the gene is transcriptionally inactive. Our aim was to identify fragile X syndrome among children with intellectual disability in Saudi Arabia. The study included 63 patients (53 males, 10 females) presented with intellectual disability, 29 normal subjects, and 23 other family members. DNA samples from six patients previously diagnosed with fragile X syndrome by Southern blot technique were used as positive controls. The method was based on bisulfite treatment of DNA followed by two different techniques. The first technique applied polymerase chain reaction amplification using one set of primers specific for amplifying methylated CpG dinucleotide region; another set designed to amplify the unmethylated CGG repeats. The second technique used the methylation-specific melting curve analysis for detection of methylation status of the FMR1 promoter region. Molecular testing using methylation sensitive polymerase chain reaction had shown amplified products in all normal subjects using unmethylated but not methylated primers indicating normal alleles, whereas amplified products were obtained using methylated polymerase chain reaction primers in fragile X syndrome-positive samples and in 9 of 53 males, indicating affected individuals. Molecular testing using melting curve analysis has shown a single low melting peak in all normal males and in (44/53) patients indicating unmethylated FMR1 gene, whereas high melting peak indicating methylated gene was observed in the fragile X syndrome-positive samples and in 9 of 53 patients. We found 100% concordance between results of both techniques and the results of Southern blot analysis. Three samples have shown both methylated and unmethylated alleles, indicating possible

  16. Molecular Photocrystallography:A Study of Metastable and Transient Species by Non-Ambient Crystallographic Techniques

    OpenAIRE

    Hatcher, L E

    2014-01-01

    This thesis describes the synthesis and crystallisation of a selection of known and novel transition-metal – nitrite complexes and their detailed study using non-ambient X-ray diffraction techniques. These coordination compounds are specifically investigated for their ability to undergo nitro – nitrito linkage isomerisation in the single-crystal, with conversion between isomers achieved on either thermal- or photoactivation. The lifetime of the excited-state isomer is strongly dependent on th...

  17. Biological, serological and molecular techniques to xanthomonas axonopodis pv. Ci tri Asymptomatic detection

    International Nuclear Information System (INIS)

    Peyrou, M.; Del Campo, R.; Russi, P.; Mara, H.; Rigamonti, N.; Larrechart, L.; Perez, E.

    2012-01-01

    Xanthomonas axonopodis pv. ci tri (X ac) produces citrus canker disease in all citrus commercial species. The bacteria can be disseminated through vegetative propagation material in asymptomatic form. To optimize bacteria detection techniques applicable to asymptomatic citrus plant tissue routine analysis, ELISA, Immunofluorescence, Pcr, qRT P CR and host plant inoculation (bioassay) diagnostic techniques were compared. Tests were made from decimal dilutions between 108 uf6.ml-1 and 102 ufc.mL-1 using a pure culture of 49b strain.The detection level obtained was 1.8 x 102 ufc.mL-1 using Inmunofluorescence; 1.8x104 ufc.mL-1 with indirect ELISA, 1.8 x 103 ufc.mL-1 by means of PCR; 10 ufc.mL-1 through of qRT P CR and 230 ufc.mL-1 in sour orange inoculated plants. The experiment was repeated at least three times for each technique. Considering this result, and taking into account that sensitivity, practicity and cost, are important when a great number of plants need to be tested, the PCR and inoculation in host plants were those that met the best characteristics to be evaluated in asymptomatic plant material

  18. Random sampling technique for ultra-fast computations of molecular opacities for exoplanet atmospheres

    Science.gov (United States)

    Min, M.

    2017-10-01

    Context. Opacities of molecules in exoplanet atmospheres rely on increasingly detailed line-lists for these molecules. The line lists available today contain for many species up to several billions of lines. Computation of the spectral line profile created by pressure and temperature broadening, the Voigt profile, of all of these lines is becoming a computational challenge. Aims: We aim to create a method to compute the Voigt profile in a way that automatically focusses the computation time into the strongest lines, while still maintaining the continuum contribution of the high number of weaker lines. Methods: Here, we outline a statistical line sampling technique that samples the Voigt profile quickly and with high accuracy. The number of samples is adjusted to the strength of the line and the local spectral line density. This automatically provides high accuracy line shapes for strong lines or lines that are spectrally isolated. The line sampling technique automatically preserves the integrated line opacity for all lines, thereby also providing the continuum opacity created by the large number of weak lines at very low computational cost. Results: The line sampling technique is tested for accuracy when computing line spectra and correlated-k tables. Extremely fast computations ( 3.5 × 105 lines per second per core on a standard current day desktop computer) with high accuracy (≤1% almost everywhere) are obtained. A detailed recipe on how to perform the computations is given.

  19. Comparison of mapped and measured total ionospheric electron content using global positioning system and beacon satellite observations

    International Nuclear Information System (INIS)

    Lanyi, G.E.; Roth, T.

    1988-01-01

    Total ionospheric electron contents (TEC) were measured by global positioning system (GPS) dual-frequency receivers developed by the Jet Propulsion Laboratory. The measurements included P-code (precise ranging code) and carrier phase data for six GPS satellites during multiple five-hour observing sessions. A set of these GPS TEC measurements were mapped from the GPS lines of sight to the line of sight of a Faraday beacon satellite by statistically fitting the TEC data to a simple model of the ionosphere. The mapped GPS TEC values were compared with the Faraday rotation measurements. Because GPS transmitter offsets are different for each satellite and because some GPS receiver offsets were uncalibrated, the sums of the satellite and receiver offsets were estimated simultaneously with the TEC in a least squares procedure. The accuracy of this estimation procedure is evaluated indicating that the error of the GPS-determined line of sight TEC can be at or below 1 x 10 to the 16th el/sq cm. Consequently, the current level of accuracy is comparable to the Faraday rotation technique; however, GPS provides superior sky coverage. 15 references

  20. Preliminary physiological characteristics of thermotolerant Saccharomyces cerevisiae clinical isolates identified by molecular biology techniques.

    Science.gov (United States)

    Siedlarz, P; Sroka, M; Dyląg, M; Nawrot, U; Gonchar, M; Kus-Liśkiewicz, M

    2016-03-01

    The aim of the study was a molecular identification and physiological characteristic of the five Saccharomyces cerevisiae strains isolated from patients. The tested isolates were compared with control strains (which are of laboratory or commercial origin). The relation of the isolates to baker's yeast S. cerevisiae was studied using species-specific primers in PCR analysis of the ITS-26S region of DNA. Five isolates were genetically identified as the yeast belonging to the genus S. cerevisiae. The effects of temperature and carbon sources on the growth of the yeast strains were analysed. A quantitative characterization of growth kinetics approve that some tested isolates are thermotolerant and are able to grow at range 37-39°C. Among them, one representative is characterized by the highest specific growth rate (0·637 h(-1) ). In conclusions, some strains are defined as potential candidates to use in the biotechnology due to a higher growth rate at elevated temperatures. Screening for further evaluation of biotechnological significance of the tested isolates will be done (e.g. ethanol and trehalose production at higher temperatures). The physiological characterization and confirmation of species identification by molecular methods for yeasts important in the context of biotechnology industry were demonstrated. Thermotolerant microbial strains are required in various industrial applications, for improving productivity and for decreasing the risk of undesirable contaminations when higher temperatures are used. It is important to search for such strains in extreme environments or exotic niches. In this paper, new thermotolerant strains were identified belonging to the Saccharomyces cerevisiae, but differed from typical bakers' yeast, essentially by their growth rate at higher temperature. The described yeast strains are promising for using in biotechnological industry, especially, for production of ethanol and other products at higher temperatures. © 2015 The

  1. Inferring divergence times within pikas (Ochotona spp.) using mtDNA and relaxed molecular dating techniques.

    Science.gov (United States)

    Lanier, Hayley C; Olson, Link E

    2009-10-01

    Although several studies have recently addressed phylogenetic relationships among Asian pikas (Ochotona spp.), the North American species have been relatively neglected and their monophyly generally unquestioned or assumed. Given the high degree of intraspecific diversity in pelage and call structure, the recent identification of previously unrecognized species of pika in Asia, and the increasing evidence for multiple trans-Beringian dispersals in several small mammal lineages, the monophyly of North American pikas warrants reexamination. In addition, previous studies have applied an externally calibrated rate to examine the timing of diversification within the genus. This method has been increasingly shown to return results that, at the very least, are overly narrow in their confidence intervals, and at the worst can be entirely spurious. For this study we combined GenBank sequences from the mitochondrial genes cyt b and ND4 with newly generated sequence data from O. hyperborea and O. collaris to investigate the origin of the North American lineages and the timing of phylogenetic diversification within the genus Ochotona. Specifically, we address three goals (1) summarize and reanalyze the molecular evidence for relationships within the genus using statistically supported models of evolution; (2) add additional sequences from O. collaris and O. hyperborea to rigorously test the monophyly of North American pikas; (3) examine the timing of the diversification within the genus using relaxed molecular clock methods. We found no evidence of multiple trans-Beringian dispersals into North America, thereby supporting the traditional hypothesis of a single invasion of North America. We also provide evidence that the major splits within the genus occurred in the Miocene, and the Nearctic pikas diverged sometime before the Pleistocene.

  2. Molecular detection and variability of Strawberry vein banding virus

    Czech Academy of Sciences Publication Activity Database

    Hanzlíková-Vašková, Dana; Špak, Josef

    2004-01-01

    Roč. 656, - (2004), 33-38 ISSN 0567-7572 Grant - others:EU EU QLR5-1999-1553 Institutional research plan: CEZ:AV0Z5051902 Keywords : AmpliDet RNA * caulimovirus * molecular beacon * nucleic acid sequence based amplification * PCR, SVBV * CaM Subject RIV: EE - Microbiology, Virology

  3. Withania somnifera: Advances and Implementation of Molecular and Tissue Culture Techniques to Enhance Its Application

    Directory of Open Access Journals (Sweden)

    Vibha Pandey

    2017-08-01

    Full Text Available Withania somnifera, commonly known as Ashwagandha an important medicinal plant largely used in Ayurvedic and indigenous medicine for over 3,000 years. Being a medicinal plant, dried powder, crude extract as well as purified metabolies of the plant has shown promising therapeutic properties. Withanolides are the principal metabolites, responsible for the medicinal properties of the plant. Availability and amount of particular withanolides differ with tissue type and chemotype and its importance leads to identification characterization of several genes/ enzymes related to withanolide biosynthetic pathway. The modulation in withanolides can be achieved by controlling the environmental conditions like, different tissue culture techniques, altered media compositions, use of elicitors, etc. Among all the in vitro techniques, hairy root culture proved its importance at industrial scale, which also gets benefits due to more accumulation (amount and number of withanolides in roots tissues of W. somnifera. Use of media compostion and elicitors further enhances the amount of withanolides in hairy roots. Another important modern day technique used for accumulation of desired secondary metabolites is modulating the gene expression by altering environmental conditions (use of different media composition, elicitors, etc. or through genetic enginnering. Knowing the significance of the gene and the key enzymatic step of the pathway, modulation in withanolide contents can be achieved upto required amount in therapeutic industry. To accomplish maximum productivity through genetic enginnering different means of Withania transformation methods have been developed to obtain maximum transformation efficiency. These standardized transformation procedues have been used to overexpress/silence desired gene in W. somnifera to understand the outcome and succeed with enhanced metabolic production for the ultimate benefit of human race.

  4. Withania somnifera: Advances and Implementation of Molecular and Tissue Culture Techniques to Enhance Its Application

    Science.gov (United States)

    Pandey, Vibha; Ansari, Waquar Akhter; Misra, Pratibha; Atri, Neelam

    2017-01-01

    Withania somnifera, commonly known as Ashwagandha an important medicinal plant largely used in Ayurvedic and indigenous medicine for over 3,000 years. Being a medicinal plant, dried powder, crude extract as well as purified metabolies of the plant has shown promising therapeutic properties. Withanolides are the principal metabolites, responsible for the medicinal properties of the plant. Availability and amount of particular withanolides differ with tissue type and chemotype and its importance leads to identification characterization of several genes/ enzymes related to withanolide biosynthetic pathway. The modulation in withanolides can be achieved by controlling the environmental conditions like, different tissue culture techniques, altered media compositions, use of elicitors, etc. Among all the in vitro techniques, hairy root culture proved its importance at industrial scale, which also gets benefits due to more accumulation (amount and number) of withanolides in roots tissues of W. somnifera. Use of media compostion and elicitors further enhances the amount of withanolides in hairy roots. Another important modern day technique used for accumulation of desired secondary metabolites is modulating the gene expression by altering environmental conditions (use of different media composition, elicitors, etc.) or through genetic enginnering. Knowing the significance of the gene and the key enzymatic step of the pathway, modulation in withanolide contents can be achieved upto required amount in therapeutic industry. To accomplish maximum productivity through genetic enginnering different means of Withania transformation methods have been developed to obtain maximum transformation efficiency. These standardized transformation procedues have been used to overexpress/silence desired gene in W. somnifera to understand the outcome and succeed with enhanced metabolic production for the ultimate benefit of human race. PMID:28848589

  5. Molecular beacon nanosensors for live cell detection and tracking differentiation and reprogramming

    DEFF Research Database (Denmark)

    Ilieva, Mirolyuba

    2013-01-01

    High-sensitive and high-affinity methods to measure gene expression inside living cells have proven to be invaluable in regards to understanding fundamental processes such as cell differentiation, reprogramming, regeneration and cancer genesis. One tool for transcription visualization on single...

  6. Phospholipid Membrane Protection by Sugar Molecules during Dehydration—Insights into Molecular Mechanisms Using Scattering Techniques

    Directory of Open Access Journals (Sweden)

    Ben Kent

    2013-04-01

    Full Text Available Scattering techniques have played a key role in our understanding of the structure and function of phospholipid membranes. These techniques have been applied widely to study how different molecules (e.g., cholesterol can affect phospholipid membrane structure. However, there has been much less attention paid to the effects of molecules that remain in the aqueous phase. One important example is the role played by small solutes, particularly sugars, in protecting phospholipid membranes during drying or slow freezing. In this paper, we present new results and a general methodology, which illustrate how contrast variation small angle neutron scattering (SANS and synchrotron-based X-ray scattering (small angle (SAXS and wide angle (WAXS can be used to quantitatively understand the interactions between solutes and phospholipids. Specifically, we show the assignment of lipid phases with synchrotron SAXS and explain how SANS reveals the exclusion of sugars from the aqueous region in the particular example of hexagonal II phases formed by phospholipids.

  7. Risk organ preservation technique in reirradiation. Injection of native type high molecular weight hyaluronate

    International Nuclear Information System (INIS)

    Kishi, Kazushi; Noda, Yasutaka; Tanaka, Kayo

    2012-01-01

    We developed a practical method of brachytherapy effective for reirradiation, using hyaluronate gel injection to separate the target to be intensively. We intended curative reirradiation with preserving organs at risk. Native-type high molecular weight hyaluronate that has an ideal biologic property to reduce inflammation via inhibitory activity to CD44 and other inflammation receptors was injected to create space during radiotherapy. Rectum, small intestines, skin, and various normal organs are effectively separated and thus eradicative re-irradiation was carried out in safe. We reviewed 55 patients who required the method. There were no complications related to the procedure. Prescribed dose to 100% of the planning target volume (PTV) was 77.93 Gy (range 54-92) equivalent at alpha/beta ratio of 3, with much higher subvolume effect, and the saving effects were enhanced at 3.35 times in the average of those without gel injection. In conclusion, the interventional brachytherapy with hyaluronate gel injection provided 3.35 times safer dose-escalated and eradicative treatment in reirradiation. (author)

  8. Implementation of Molecular Gradients for Local Hybrid Density Functionals Using Seminumerical Integration Techniques.

    Science.gov (United States)

    Klawohn, Sascha; Bahmann, Hilke; Kaupp, Martin

    2016-09-13

    We present the first implementation of the derivative of the local hybrid exchange-correlation energy with respect to the displacement of nuclei in a Gaussian-type atomic basis set. This extends a recent efficient implementation of local hybrid functionals for self-consistent Kohn-Sham and linear-response TDDFT calculations into the TURBOMOLE program package. In contrast to seminumerical schemes for global exact-exchange admixtures and to the related SCF and TDDFT implementations of local hybrid functionals, additional analytical integrals have to be evaluated at each grid point in the case of molecular gradients. The overall efficiency of the present scheme is improved through prescreening with the density matrix (P-junctions), as well as with spherical overlap estimates (S-junctions). Comparative timings for structure optimizations with local vs global hybrid functionals are discussed while gauging the accuracy for S- and P-junctions using varying thresholds. Local hybrids are furthermore assessed for structure optimization and harmonic vibrational frequency calculations (using numerical second derivatives) of a selection of test systems, comparing with experimental data and some widely used density functionals.

  9. Performance of parasitological and molecular techniques for the diagnosis and surveillance of gambiense sleeping sickness.

    Directory of Open Access Journals (Sweden)

    Dieudonné Mumba Ngoyi

    2014-06-01

    Full Text Available Recently, improvements have been made to diagnostics for gambiense sleeping sickness control but their performance remains poorly documented and may depend on specimen processing prior to examination. In a prospective study in the Democratic Republic of the Congo, we compared the diagnostic performance of several parasite detection techniques, immune trypanolysis and of m18S PCR on whole blood stored in a stabilisation buffer or dried on filter paper.Individuals with CATT whole blood (WB titer ≥1∶4 or with clinical signs indicative for sleeping sickness were examined for presence of trypanosomes in lymph node aspirate (LNA and/or in blood. Blood was examined with Capillary Centrifugation Technique (CTC, mini-Anion Exchange Centrifugation Technique (mAECT and mAECT on buffy coat (BC. PCR was performed on whole blood (i stored in guanidine hydrochloride EDTA (GE stabilisation buffer and (ii dried on filter paper, and repeatability and reproducibility were assessed. Immune trypanolysis (TL was performed on plasma.A total of 237 persons were included. Among 143 parasitologically confirmed cases, 85.3% had a CATT-WB titre of ≥1/8, 39.2% were positive in LNA, 47.5% in CTC, 80.4% in mAECT-WB, 90.9% in mAECT-BC, 95.1% in TL and up to 89.5% in PCR on GE-stabilised blood. PCR on GE-stabilised blood showed highest repeatability (87.8% and inter-laboratory reproducibility (86.9%. Of the 94 non-confirmed suspects, respectively 39.4% and 23.4% were TL or PCR positive. Suboptimal specificity of PCR and TL was also suggested by latent class analysis.The combination of LNA examination with mAECT-BC offered excellent diagnostic sensitivity. For PCR, storage of blood in stabilisation buffer is to be preferred over filter paper. TL as well as PCR are useful for remote diagnosis but are not more sensitive than mAECT-BC. For TL and PCR, the specificity, and thus usefulness for management of non-confirmed suspects remain to be determined.

  10. Molecular techniques for the personalised management of patients with chronic myeloid leukaemia.

    Science.gov (United States)

    Alikian, Mary; Gale, Robert Peter; Apperley, Jane F; Foroni, Letizia

    2017-03-01

    Chronic myeloid leukemia (CML) is the paradigm for targeted cancer therapy. RT-qPCR is the gold standard for monitoring response to tyrosine kinase-inhibitor (TKI) therapy based on the reduction of blood or bone marrow BCR-ABL1 . Some patients with CML and very low or undetectable levels of BCR-ABL1 transcripts can stop TKI-therapy without CML recurrence. However, about 60 percent of patients discontinuing TKI-therapy have rapid leukaemia recurrence. This has increased the need for more sensitive and specific techniques to measure residual CML cells. The clinical challenge is to determine when it is safe to stop TKI-therapy. In this review we describe and critically evaluate the current state of CML clinical management, different technologies used to monitor measurable residual disease (MRD) focus on comparingRT-qPCR and new methods entering clinical practice. We discuss advantages and disadvantages of new methods.

  11. A nonlinear OPC technique for laser beam control in turbulent atmosphere

    Science.gov (United States)

    Markov, V.; Khizhnyak, A.; Sprangle, P.; Ting, A.; DeSandre, L.; Hafizi, B.

    2013-05-01

    A viable beam control technique is critical for effective laser beam transmission through turbulent atmosphere. Most of the established approaches require information on the impact of perturbations on wavefront propagated waves. Such information can be acquired by measuring the characteristics of the target-scattered light arriving from a small, preferably diffraction-limited, beacon. This paper discusses an innovative beam control approach that can support formation of a tight laser beacon in deep turbulence conditions. The technique employs Brillouin enhanced fourwave mixing (BEFWM) to generate a localized beacon spot on a remote image-resolved target. Formation of the tight beacon doesn't require a wavefront sensor, AO system, or predictive feedback algorithm. Unlike conventional adaptive optics methods which allow wavefront conjugation, the proposed total field conjugation technique is critical for beam control in the presence of strong turbulence and can be achieved by using this non-linear BEFWM technique. The phase information retrieved from the established beacon beam can then be used in conjunction with an AO system to propagate laser beams in deep turbulence.

  12. Novel technique for spatially resolved imaging of molecular bond orientations using x-ray birefringence

    Energy Technology Data Exchange (ETDEWEB)

    Sutter, John P., E-mail: john.sutter@diamond.ac.uk; Dolbnya, Igor P.; Collins, Stephen P. [Diamond Light Source Ltd, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 0DE (United Kingdom); Harris, Kenneth D. M., E-mail: HarrisKDM@cardiff.ac.uk; Edwards-Gau, Gregory R.; Kariuki, Benson M. [School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT (United Kingdom); Palmer, Benjamin A. [Department of Structural Biology, Weizmann Institute of Science, 234 Herzl St., Rehovot 7610001 (Israel)

    2016-07-27

    Birefringence has been observed in anisotropic materials transmitting linearly polarized X-ray beams tuned close to an absorption edge of a specific element in the material. Synchrotron bending magnets provide X-ray beams of sufficiently high brightness and cross section for spatially resolved measurements of birefringence. The recently developed X-ray Birefringence Imaging (XBI) technique has been successfully applied for the first time using the versatile test beamline B16 at Diamond Light Source. Orientational distributions of the C–Br bonds of brominated “guest” molecules within crystalline “host” tunnel structures (in thiourea or urea inclusion compounds) have been studied using linearly polarized incident X-rays near the Br K-edge. Imaging of domain structures, changes in C–Br bond orientations associated with order-disorder phase transitions, and the effects of dynamic averaging of C–Br bond orientations have been demonstrated. The XBI setup uses a vertically deflecting high-resolution double-crystal monochromator upstream from the sample and a horizontally deflecting single-crystal polarization analyzer downstream, with a Bragg angle as close as possible to 45°. In this way, the ellipticity and rotation angle of the polarization of the beam transmitted through the sample is measured as in polarizing optical microscopy. The theoretical instrumental background calculated from the elliptical polarization of the bending-magnet X-rays, the imperfect polarization discrimination of the analyzer, and the correlation between vertical position and photon energy introduced by the monochromator agrees well with experimental observations. The background is calculated analytically because the region of X-ray phase space selected by this setup is sampled inefficiently by standard methods.

  13. Investigation of three flavonoids binding to bovine serum albumin using molecular fluorescence technique

    International Nuclear Information System (INIS)

    Bi Shuyun; Yan Lili; Pang Bo; Wang Yu

    2012-01-01

    The three flavonoids including naringenin, hesperetin and apigenin binding to bovine serum albumin (BSA) at pH 7.4 was studied by fluorescence quenching, synchronous fluorescence and UV-vis absorption spectroscopic techniques. The results obtained revealed that naringenin, hesperetin and apigenin strongly quenched the intrinsic fluorescence of BSA. The Stern-Volmer curves suggested that these quenching processes were all static quenching processes. At 291 K, the value and the order of the binding constant were K A n aringenin) =4.08x10 4 A(hesperetin) =5.40x10 4 ∼K A(apigenin) =5.32x10 4 L mol -1 . The main binding force between the flavonoid and BSA was hydrophobic and electrostatic force. According to the Foerster theory of non-radiation energy transfer, the binding distances (r 0 ) were obtained as 3.36, 3.47 and 3.30 nm for naringenin-BSA, hesperetin-BSA and apigenin-BSA, respectively. The effect of some common ions such as Fe 3+ , Cu 2+ , Mg 2+ , Mn 2+ , Zn 2+ and Ca 2+ on the binding was also studied in detail. The competition binding was also performed. The apparent binding constant (K' A ) obtained suggested that one flavonoid had an obvious effect on the binding of another flavonoid to protein when they coexisted in BSA solution. - Highlights: → Quenchings of BSA fluorescence by the flavonoids was all static quenchings. → Synchronous fluorescence was applied to study the structural change of BSA. → Binding constant, binding site and binding force were determined. → Competition binding experiments were performed. → One flavonoid had an obvious effect on the binding of another one to BSA.

  14. A brief review on molecular, genetic and imaging techniques for HCV fibrosis evaluation

    Directory of Open Access Journals (Sweden)

    Sumrin Aleena

    2011-02-01

    Full Text Available Abstract Background Chronic HCV is one of the major causes of morbidity and mortality in the present day world. The assessment of disease progression not only provides useful information for diagnosis and therapeutic supervision judgment but also for monitoring disease. Different invasive and non invasive methods are applied to diagnose the disease from initial to end stage (mild fibrosis to cirrhosis. Although, liver biopsy is still considered as gold standard to identify liver histological stages, an assessment of the disease development based on non-invasive clinical findings is also emerging and this may replace the need of biopsy in near future. This review gives brief insight on non-invasive methods currently available for predicting liver fibrosis in HCV with their current pros and cons to make easier for a clinician to choose better marker to assess liver fibrosis in HCV infected patients. Methods More than 200 studies regarding invasive and noninvasive markers available for HCV liver disease diagnosis were thoroughly reviewed. We examined year wise results of these markers based on their sensitivity, specificity, PPV, NPV and AUROCs. Results We found that in all non-invasive serum markers for HCV, FibroTest, Forn's Index, Fibrometer and HepaScore have high five-year predictive value but with low AUROCs (0.60~0.85 and are not comparable to liver biopsy (AUROC = 0.97. Even though from its beginning, Fibroscan is proved to be best with high AUROCs (> 0.90 in all studies, no single noninvasive marker is able to differentiate all fibrosis stages from end stage cirrhosis. Meanwhile, specific genetic markers may not only discriminate fibrotic and cirrhotic liver but also differentiate individual fibrosis stages. Conclusions There is a need of marker which accurately determines the stage based on simplest routine laboratory test. Genetic marker in combination of imaging technique may be the better non invasive diagnostic method in future.

  15. Size-exclusion chromatography (HPLC-SEC) technique optimization by simplex method to estimate molecular weight distribution of agave fructans.

    Science.gov (United States)

    Moreno-Vilet, Lorena; Bostyn, Stéphane; Flores-Montaño, Jose-Luis; Camacho-Ruiz, Rosa-María

    2017-12-15

    Agave fructans are increasingly important in food industry and nutrition sciences as a potential ingredient of functional food, thus practical analysis tools to characterize them are needed. In view of the importance of the molecular weight on the functional properties of agave fructans, this study has the purpose to optimize a method to determine their molecular weight distribution by HPLC-SEC for industrial application. The optimization was carried out using a simplex method. The optimum conditions obtained were at column temperature of 61.7°C using tri-distilled water without salt, adjusted pH of 5.4 and a flow rate of 0.36mL/min. The exclusion range is from 1 to 49 of polymerization degree (180-7966Da). This proposed method represents an accurate and fast alternative to standard methods involving multiple-detection or hydrolysis of fructans. The industrial applications of this technique might be for quality control, study of fractionation processes and determination of purity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Study on the interaction of tussilagone with human serum albumin (HSA) by spectroscopic and molecular docking techniques

    Science.gov (United States)

    Xu, Liang; Hu, Yan-Xi; Li, Yan-Cheng; Zhang, Li; Ai, Hai-Xin; Liu, Hong-Sheng; Liu, Yu-Feng; Sang, Yu-Li

    2017-12-01

    Tussilagone is a sesquiterpenoid which exhibits a variety of pharmacological activities. The interaction of tussilagone with human serum albumin (HSA) was investigated using fluorescence spectroscopy, UV-vis absorption, fluorescence probe experiments, synchronous fluorescence, circular dichroism (CD) spectra, three-dimensional spectra and molecular docking techniques under simulative physiological conditions. The results clarified that the fluorescence quenching of HSA by tussilagone was a static quenching process as a result of HSA-tussilagone (1:1) complex. Tussilagone spontaneously bound to HSA in site I (subdomain IIA), which was primarily driven by hydrophobic forces and hydrogen bonds (ΔH° = -13.89 kJ mol-1, ΔS° = 16.39 J mol-1 K-1). The binding constant was calculated to be 2.182 × 103 L mol-1 and the binding distance was estimated to be 2.07 nm at 291 K, showing the occurrence of fluorescence energy transfer. The results of CD, synchronous and three-dimensional fluorescence spectra all revealed that tussilagone induced the conformational changes of HSA. Meanwhile, the study of molecular docking also indicated that tussilagone could bind to the site I of HSA mainly by hydrophobic and hydrogen bond interactions.

  17. Interaction of an antiepileptic drug, lamotrigine with human serum albumin (HSA): Application of spectroscopic techniques and molecular modeling methods.

    Science.gov (United States)

    Poureshghi, Fatemeh; Ghandforoushan, Parisa; Safarnejad, Azam; Soltani, Somaieh

    2017-01-01

    Lamotrigine (an epileptic drug) interaction with human serum albumin (HSA) was investigated by fluorescence, UV-Vis, FTIR, CD spectroscopic techniques, and molecular modeling methods. Binding constant (K b ) of 5.74×10 3 and number of binding site of 0.97 showed that there is a slight interaction between lamotrigine and HSA. Thermodynamic studies was constructed using the flourimetric titrations in three different temperatures and the resulted data used to calculate the parameters using Vant Hoff equation. Decreased Stern Volmer quenching constant by enhanced temperature revealed the static quenching mechanism. Negative standard enthalpy (ΔH) and standard entropy (ΔS) changes indicated that van der Waals interactions and hydrogen bonds were dominant forces which facilitate the binding of Lamotrigine to HSA, the results were confirmed by molecular docking studies which showed no hydrogen binding. The FRET studies showed that there is a possibility of energy transfer between Trp214 and lamotrigine. Also the binding of lamotrigine to HSA in the studied concentrations was not as much as many other drugs, but the secondary structure of the HSA was significantly changed following the interaction in a way that α-helix percentage was reduced from 67% to 57% after the addition of lamotrigine in the molar ratio of 4:1 to HSA. According to the docking studies, lamotrigine binds to IB site preferably. Copyright © 2016. Published by Elsevier B.V.

  18. Dead Reckoning Localization Technique for Mobile Wireless Sensor Networks

    OpenAIRE

    Rashid, Haroon; Turuk, Ashok Kumar

    2015-01-01

    Full paper at: http://arxiv.org/pdf/1504.06797.pdfThis paper shows how a mobile node can be localized with less than three beacon nodes. It uses a technique known as dead-reckoning for localization of nodes at specific intervals

  19. Recent research on inherent molecular structure, physiochemical properties, and bio-functions of food and feed-type Avena sativa oats and processing-induced changes revealed with molecular microspectroscopic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Prates, Luciana Louzada [Department of Animal and Poultry Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; Yu, Peiqiang [Department of Animal and Poultry Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

    2017-05-16

    Avena sativa oat is a cereal widely used as human food and livestock feed. However, the low metabolized energy and the rapid rumen degradations of protein and starch have limited the use of A. sativa oat grains. To overcome this disadvantage, new A. sativa oat varieties have been developed. Additionally, heat-related processing has been performed to decrease the degradation rate and improve the absorption of amino acids in the small intestine. The nutritive value is reflected by both chemical composition and inherent molecular structure conformation. However, the traditional wet chemical analysis is not able to detect the inherent molecular structures within an intact tissue. The advanced synchrotron-radiation and globar-based molecular microspectroscopy have been developed recently and applied to study internal molecular structures and the processing induced structure changes in A. sativa oats and reveal how molecular structure changes in relation to nutrient availability. This review aimed to obtain the recent information regarding physiochemical properties, molecular structures, metabolic characteristics of protein, and the heat-induced changes in new A. sativa oat varieties. The use of the advanced vibrational molecular spectroscopy was emphasized, synchrotron- and globar-based (micro)spectroscopy, to reveal the inherent structure of A. sativa oats at cellular and molecular levels and to reveal the heat processing effect on the degradation characteristics and the protein molecular structure in A. sativa oats. The relationship between nutrient availability and protein molecular inherent structure was also presented. Information described in this review gives better insight in the physiochemical properties, molecular structure, and the heat-induced changes in A. sativa oat detected with advanced molecular spectroscopic techniques in combinination with conventional nutrition study techniques.

  20. Decentralized Single-beacon Acoustic Navigation: Combined Communication and Navigation for Underwater Vehicles

    Science.gov (United States)

    2010-06-01

    navigation beacons. When the modem is in synchronous navigation ( SNV ) mode, as described in [39], the modem’s clock can be synchronized to a PPS signal using...In SNV mode, all transmitted messages are initiated by the modem within ± 10 µs of the rising edge of the PPS signal [39]. 3.3.2 PPSBoard The PPSBoard...reference for use subsea that can be synchronized to a GPS timing signal. In addition to supplying a PPS signal to the Micro- Modem to enable its SNV

  1. Optical Measurement of a Compressible Shear Layer Using a Laser-Induced Air Breakdown Beacon (Preprint)

    Science.gov (United States)

    2009-12-01

    Comrol Unil’ersity of NOire Dame. Notre Dame. IN. 46556 David Goorskei, Matthew R. Whiteley4 MZA Associates Corporation, Dayton. OH. 45459 David...Cavalieri s, and Eric J. Jumper6 Cenler for Flow Physics and Comrol University of NOire Dame. Noire Dame. IN. 46556 The aero-optic aberrations due to...wave fronts. th3t limit the ability of the beacon system to detect aero-optic aberrations that ha\\’e an amplitude below the noi5e level. Figure 3

  2. A mobile indoor positioning system based on iBeacon technology.

    Science.gov (United States)

    Lin, Xin-Yu; Ho, Te-Wei; Fang, Cheng-Chung; Yen, Zui-Shen; Yang, Bey-Jing; Lai, Feipei

    2015-01-01

    To increase the efficiency in the emergency room, the goal of this research is to implement a mobile-based indoor positioning system using mobile applications (APP) with the iBeacon solution based on the Bluetooth Low Energy (BLE) technology. We use the Received Signal Strength (RSS) based localization method to estimate the patients' locations. Our positioning algorithm achieves 97.22% (95% Confidence Interval = 95.90% - 98.55%) accuracy of classification. As the result, our mechanism is reliable enough to satisfy the need for medical staff to track the locations of their patients.

  3. The Southeastern Minnesota Beacon Project for Community-driven Health Information Technology: Origins, Achievements, and Legacy.

    Science.gov (United States)

    Chute, Christopher G; Hart, Lacey A; Alexander, Alex K; Jensen, Daniel W

    2014-01-01

    The Southeastern (SE) Minnesota Beacon organized all the health care providers, county public health organizations, and school districts in the deployment and integration of health information exchange (HIE) and targeted health communication around childhood asthma and diabetes. The community cooperated to establish a clinical data repository for all residents in the 11-county region. Through this community of practice approach that involved traditional and nontraditional providers, the SE Minnesota Beacon was able to realize unique applications of this technology. This manuscript overviews the associated organization and infrastructure of this community collaboration. The Office of the National Coordinator for Health Information Technology (ONC), as part of the American Recovery and Reinvestment Act of 2009 (ARRA) stimulus, established 17 projects throughout the United States targeting the introduction and meaningful use of health information technology (HIT). These 17 communities were intended to serve as an example of what could be accomplished. The SE Minnesota Beacon is one of these communities. The community ultimately opted for peer-to-peer HIE, using Nationwide Health Information Network (NwHIN) Connect software. The clinical data repository was established using the infrastructure developed by the Regenstrief Institute, which operated as a trusted third party. As an extension to HIE, the consortium of county public health departments created a patient data portal for use by school nurses and parents. Childhood asthma was addressed by creating, exchanging, and maintaining an "asthma action plan" for each affected child, shared throughout the community, including through the patient portal. Diabetes management introduced patient treatment decision tools and patient quality of life measures, facilitating care. Influenza vaccination was enhanced by large-scale community reporting in partnership with the state vaccination registry. The methodology and

  4. Perancangan Prototipe Receiver Beacon Black Box Locator Acoustic 37,5 kHz Pingers

    Directory of Open Access Journals (Sweden)

    RUSTAMAJI RUSTAMAJI

    2016-02-01

    Full Text Available ABSTRAK Ketika suatu pesawat terbang mengalami kecelakaan terjatuh ke dalam air, maka lokasi keberadaannya dapat dideteksi oleh alat yang disebut receiver beacon black box locator acoustic (pingers receiver. Pingers receiver berfungsi untuk menerima sinyal dengan frekuensi 37,5 kHz ± 1 kHz dari pingers transmitter atau Underwater Locator Beacon (ULB yang berada pada black box pesawat. Dalam penelitian ini dibuat perancangan pingers receiver yang tersusun dari rangkaian Band Pass Filter (BPF, detektor selubung, penguat audio, dan loud speaker. Frekuensi sinyal 37,5 kHz ± 1 kHz yang dikirim oleh pingers transmitter akan diterima oleh pingers receiver, dimana tahap pertama melewati rangkaian Band Pass Filter (BPF selanjutnya sinyal akan dideteksi oleh detektor selubung untuk mengambil kembali sinyal informasi yang berupa sinyal pulsa dengan lebar pulsa 10 milidetik dan interval 1 detik sebagai sinyal pingers yang nantinya mampu didengar oleh telinga manusia. Berdasarkan perancangan yang telah dibuat, output sinyal yang dihasilkan oleh prototipe pingers receiver tersebut memiliki lebar pulsa 14 milidetik dengan interval 1 detik. Kata kunci: pingers receiver, band pass filter (BPF, detektor selubung, loud speaker. ABSTRACT When an aircraft caught in an accident and crashes into the water, its location can be detected using a device called a receiver beacon black box locator acoustic (pingers receiver. The pingers receiver functioned as a reciever signal with 37,5 kHz ± 1 kHz frequency from trnasmitter pingers or Underwater Locator Beacon (ULB which is on air plane black blox. In this research made design pingers receiver composed of a series of  Band Pass Filter (BPF, envelope detector, audio amplifier, and loud speaker. The signal of 37,5 kHz ± 1 kHz  frequency sent by pingers transmitter will bereceived by pingers receiver, after which the signal will be processed by the Band Pass Filter (BPF circuit before being detected by envelope detector

  5. Diphtheria in the Republic of Georgia: Use of Molecular Typing Techniques for Characterization of Corynebacterium diphtheriae Strains

    Science.gov (United States)

    Sulakvelidze, Alexander; Kekelidze, Merab; Gomelauri, Tsaro; Deng, Yingkang; Khetsuriani, Nino; Kobaidze, Ketino; De Zoysa, Aruni; Efstratiou, Androulla; Morris, J. Glenn; Imnadze, Paata

    1999-01-01

    Sixty-six Corynebacterium diphtheriae strains (62 of the gravis biotype and 4 of the mitis biotype) isolated during the Georgian diphtheria epidemic of 1993 to 1998 and 13 non-Georgian C. diphtheriae strains (10 Russian and 3 reference isolates) were characterized by (i) biotyping, (ii) toxigenicity testing with the Elek assay and PCR, (iii) the randomly amplified polymorphic DNA (RAPD) technique, and (iv) pulsed-field gel electrophoresis (PFGE). Fifteen selected strains were ribotyped. Six RAPD types and 15 PFGE patterns were identified among all strains examined, and 12 ribotypes were found among the 15 strains that were ribotyped. The Georgian epidemic apparently was caused by one major clonal group of C. diphtheriae (PFGE type A, ribotype R1), which was identical to the predominant epidemic strain(s) isolated during the concurrent diphtheria epidemic in Russia. A dendrogram based on the PFGE patterns revealed profound differences between the minor (nonpredominant) epidemic strains found in Georgia and Russia. The methodologies for RAPD typing, ribotyping, and PFGE typing of C. diphtheriae strains were improved to enable rapid and convenient molecular typing of the strains. The RAPD technique was adequate for biotype differentiation; however, PFGE and ribotyping were better (and equal to each other) at discriminating between epidemiologically related and unrelated isolates. PMID:10488190

  6. Preliminary Statistics from the NASA Alphasat Beacon Receiver in Milan, Italy

    Science.gov (United States)

    Nessel, James; Zemba, Michael; Morse, Jacquelynne; Luini, Lorenzo; Riva, Carlo

    2015-01-01

    NASA Glenn Research Center (GRC) and the Politecnico di Milano (POLIMI) have initiated a joint propagation campaign within the framework of the Alphasat propagation experiment to characterize rain attenuation, scintillation, and gaseous absorption effects of the atmosphere in the 40 gigahertz band. NASA GRC has developed and installed a K/Q-band (20/40 gigahertz) beacon receiver at the POLIMI campus in Milan, Italy, which receives the 20/40 gigahertz signals broadcast from the Alphasat Aldo Paraboni TDP no. 5 beacon payload. The primary goal of these measurements is to develop a physical model to improve predictions of communications systems performance within the Q-band. Herein, we provide an overview of the design and data calibration procedure, and present 6 months of preliminary statistics of the NASA propagation terminal, which has been installed and operating in Milan since May 2014. The Q-band receiver has demonstrated a dynamic range of 40 decibels at an 8-hertz sampling rate. A weather station with an optical disdrometer is also installed to characterize rain drop size distribution for correlation with physical based models.

  7. Secure Utilization of Beacons and UAVs in Emergency Response Systems for Building Fire Hazard.

    Science.gov (United States)

    Seo, Seung-Hyun; Choi, Jung-In; Song, Jinseok

    2017-09-25

    An intelligent emergency system for hazard monitoring and building evacuation is a very important application area in Internet of Things (IoT) technology. Through the use of smart sensors, such a system can provide more vital and reliable information to first-responders and also reduce the incidents of false alarms. Several smart monitoring and warning systems do already exist, though they exhibit key weaknesses such as a limited monitoring coverage and security, which have not yet been sufficiently addressed. In this paper, we propose a monitoring and emergency response method for buildings by utilizing beacons and Unmanned Aerial Vehicles (UAVs) on an IoT security platform. In order to demonstrate the practicability of our method, we also implement a proof of concept prototype, which we call the UAV-EMOR (UAV-assisted Emergency Monitoring and Response) system. Our UAV-EMOR system provides the following novel features: (1) secure communications between UAVs, smart sensors, the control server and a smartphone app for security managers; (2) enhanced coordination between smart sensors and indoor/outdoor UAVs to expand real-time monitoring coverage; and (3) beacon-aided rescue and building evacuation.

  8. A Two-Layer Method for Sedentary Behaviors Classification Using Smartphone and Bluetooth Beacons.

    Science.gov (United States)

    Cerón, Jesús D; López, Diego M; Hofmann, Christian

    2017-01-01

    Among the factors that outline the health of populations, person's lifestyle is the more important one. This work focuses on the caracterization and prevention of sedentary lifestyles. A sedentary behavior is defined as "any waking behavior characterized by an energy expenditure of 1.5 METs (Metabolic Equivalent) or less while in a sitting or reclining posture". To propose a method for sedentary behaviors classification using a smartphone and Bluetooth beacons considering different types of classification models: personal, hybrid or impersonal. Following the CRISP-DM methodology, a method based on a two-layer approach for the classification of sedentary behaviors is proposed. Using data collected from a smartphones' accelerometer, gyroscope and barometer; the first layer classifies between performing a sedentary behavior and not. The second layer of the method classifies the specific sedentary activity performed using only the smartphone's accelerometer and barometer data, but adding indoor location data, using Bluetooth Low Energy (BLE) beacons. To improve the precision of the classification, both layers implemented the Random Forest algorithm and the personal model. This study presents the first available method for the automatic classification of specific sedentary behaviors. The layered classification approach has the potential to improve processing, memory and energy consumption of mobile devices and wearables used.

  9. A Microfluidic Love-Wave Biosensing Device for PSA Detection Based on an Aptamer Beacon Probe

    Directory of Open Access Journals (Sweden)

    Feng Zhang

    2015-06-01

    Full Text Available A label-free and selective aptamer beacon-based Love-wave biosensing device was developed for prostate specific antigen (PSA detection. The device consists of the following parts: LiTaO3 substrate with SiO2 film as wave guide layer, two set of inter-digital transducers (IDT, gold film for immobilization of the biorecongniton layer and a polydimethylsiloxane (PDMS microfluidic channels. DNA aptamer, or “artificial antibody”, was used as the specific biorecognition probe for PSA capture. Some nucleotides were added to the 3'-end of the aptamer to form a duplex with the 3'-end, turning the aptamer into an aptamer-beacon. Taking advantage of the selective target-induced assembly changes arising from the “aptamer beacon”, highly selective and specific detection of PSA was achieved. Furthermore, PDMS microfluidic channels were designed and fabricated to realize automated quantitative sample injection. After optimization of the experimental conditions, the established device showed good performance for PSA detection between 10 ng/mL to 1 μg/mL, with a detection limit of 10 ng/mL. The proposed sensor might be a promising alternative for point of care diagnostics.

  10. Eutectic-based wafer-level-packaging technique for piezoresistive MEMS accelerometers and bond characterization using molecular dynamics simulations

    Science.gov (United States)

    Aono, T.; Kazama, A.; Okada, R.; Iwasaki, T.; Isono, Y.

    2018-03-01

    We developed a eutectic-based wafer-level-packaging (WLP) technique for piezoresistive micro-electromechanical systems (MEMS) accelerometers on the basis of molecular dynamics analyses and shear tests of WLP accelerometers. The bonding conditions were experimentally and analytically determined to realize a high shear strength without solder material atoms diffusing to adhesion layers. Molecular dynamics (MD) simulations and energy dispersive x-ray (EDX) spectrometry done after the shear tests clarified the eutectic reaction of the solder materials used in this research. Energy relaxation calculations in MD showed that the diffusion of solder material atoms into the adhesive layer was promoted at a higher temperature. Tensile creep MD simulations also suggested that the local potential energy in a solder material model determined the fracture points of the model. These numerical results were supported by the shear tests and EDX analyses for WLP accelerometers. Consequently, a bonding load of 9.8 kN and temperature of 300 °C were found to be rational conditions because the shear strength was sufficient to endure the polishing process after the WLP process and there was little diffusion of solder material atoms to the adhesion layer. Also, eutectic-bonding-based WLP was effective for controlling the attenuation of the accelerometers by determining the thickness of electroplated solder materials that played the role of a cavity between the accelerometers and lids. If the gap distance between the two was less than 6.2 µm, the signal gains for x- and z-axis acceleration were less than 20 dB even at the resonance frequency due to air-damping.

  11. Probing the interactions of bromchlorbuterol-HCl and phenylethanolamine A with HSA by multi-spectroscopic and molecular docking technique

    International Nuclear Information System (INIS)

    Bi, Shuyun; Zhao, Tingting; Zhou, Huifeng; Wang, Yu; Li, Zhihong

    2016-01-01

    Highlights: • Molecular docking showed that BCB/PEA was bound at sub-domain IIA of HSA. • Fluorescence lifetimes indicated that the quenching was a static quenching. • CD spectra showed that BCB/PEA changed the conformation of HSA. • The competitive binding between site markers and BCB/PEA was studied. • The mutual influence on the two drugs binding HSA was studied. - Abstract: Using fluorescence quenching, fluorescence lifetime, (UV + vis) absorption, circular dichroism (CD) and molecular docking technique, the interactions of human serum albumin (HSA) with bromchlorbuterol-HCl (BCB) and phenylethanolamine A (PEA) were investigated. The quenching rate constants and binding constants for BCB/PEA with HSA were determined at T = (292.15, 302.15 and 312.15) K respectively, which were all decreased with the increase of the temperature, showing not a dynamic quenching. The fluorescence lifetime of HSA with BCB/PEA had changed little compared to that of HSA alone (τ 0 ), further confirming that BCB/PEA quenching of intrinsic fluorescence of HSA is a static quenching. The effects of K + , Ca 2+ , Cu 2+ , Zn 2+ and Fe 3+ on the binding were studied. The analysis of the thermodynamic parameters for BCB/(PEA + HSA) showed that BCB/PEA could bind to HSA via hydrophobic force. The binding distances were determined as 2.90 and 4.11 nm for (BCB + HSA) and (PEA + HSA) based on the Förster’s non-radiative energy transfer theory (FRET). Synchronous fluorescence and CD spectra indicated that the conformation of HSA was changed by BCB/PEA. The competitive studies for the drug with site marker suggested that both BCB and PEA were bound at Sudlow’s sites I (sub-domain IIA, also known as indometacin binding site) in HSA, and the results of the study of molecular docking also leads to the same conclusion. The competitive binding experiments for the two drugs were also performed, which further indicates that PEA and BCB could share the same binding site, and PEA has a much

  12. Molecular techniques in mycobacteriology

    NARCIS (Netherlands)

    Hermans, J.

    1997-01-01

    The bacterial genus Mycobacterium belongs to the group of Grain-positive bacteria and holds many species, displaying a broad spectrum of properties. About one third is pathogenic to humans or animals, the rest of the mycobacterial species being relatively harmless soil-

  13. Molecular techniques in fisheries

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, U.

    stream_size 2 stream_content_type text/plain stream_name Genetic_Biotechnol_Tool_Aquacult_Fish_1998_60.pdf.txt stream_source_info Genetic_Biotechnol_Tool_Aquacult_Fish_1998_60.pdf.txt Content-Encoding ISO-8859-1 Content-Type text...

  14. Towards mosquito sterile insect technique programmes: exploring genetic, molecular, mechanical and behavioural methods of sex separation in mosquitoes.

    Science.gov (United States)

    Gilles, Jeremie R L; Schetelig, Marc F; Scolari, Francesca; Marec, František; Capurro, Margareth L; Franz, Gerald; Bourtzis, Kostas

    2014-04-01

    When considering a mosquito release programme, one of the first issues to be addressed is how to eliminate/separate the females. The greatest number of options might eventually be available for those who can use transgenic mosquitoes, but the inherent characteristics of the target species may also provide possibilities for interim measures until more efficient methods can be developed. Differences in intrinsic size, in behaviour and in development rate between females and males are often available and useful for sexing. Efficient species-specific systems for eliminating females at the embryo stage have been developed, but most have since been discarded due to lack of use. Ideal systems specifically kill female embryos using some treatment that can be manipulated during production. Such killing systems are far more efficient than using intrinsic sexual differences, but they systems require selectable genetic markers and sex-linkage created by rare random chromosomal rearrangements. While intrinsic sexual differences should not be considered as long-term candidates for the development of robust and efficient sexing approaches, in the absence of these, the accessibility and integration of less efficient systems can provide a stop-gap measure that allows rapid start up with a minimum of investment. The International Atomic Energy Agency is funding over a 5 year period (2013-2018) a new Coordinated Research Project on "Exploring Genetic, Molecular, Mechanical and Behavioural Methods of Sex Separation in Mosquitoes" to network researchers and to address the critical need of genetic sexing strains for the implementation of the sterile insect technique (using radiation-sterilised or transgenic male mosquitoes) and for insect incompatibility technique programmes against disease-transmitting mosquitoes. Copyright © 2013 International Atomic Energy Agency. Published by Elsevier B.V. All rights reserved.

  15. Evaluation of randomly amplified polymorphic DNA and pulsed field gel electrophoresis techniques for molecular typing of Dermatophilus congolensis.

    Science.gov (United States)

    Larrasa, José; García-Sánchez, Alfredo; Ambrose, Nicholas C; Parra, Alberto; Alonso, Juan M; Rey, Joaquín M; Hermoso-de-Mendoza, Miguel; Hermoso-de-Mendoza, Javier

    2004-11-01

    This study aimed to evaluate molecular typing methods useful for standardization of strains in experimental work on dermatophilosis. Fifty Dermatophilus congolensis isolates, collected from sheep, cattle, horse and a deer, were analyzed by randomly amplified polymorphic DNA (RAPD) method using twenty-one different primers, and the results were compared with those obtained by typing with a pulsed field gel electrophoresis (PFGE) method using the restriction digest enzyme Sse8387I. The typeability, reproducibility and discriminatory power of RAPD and Sse8387I-PFGE typing were calculated. Both typing methods were highly reproducible. Of the two techniques, Sse8387I-PFGE was the least discriminating (Dice Index (DI), 0.663) and could not distinguish between epidemiologically related isolates, whereas RAPD showed an excellent discriminatory power (DI, 0.7694-0.9722). Overall, the degree of correlation between RAPD and PFGE typing was significantly high (r, 0.8822). We conclude that the DNA profiles generated by either RAPD or PFGE can be used to differentiate epidemiologically unrelated isolates. The results of this study strongly suggest that at least two independent primers are used for RAPD typing in order to improve its discriminatory power, and that PFGE is used for confirmation of RAPD results.

  16. Molecular characterization of fossil organic matter in Glyptostrobus europaeus remains from the Orawa basin (Poland). Comparison of pyrolytic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Almendros, G.; Dorado, J.; Gonzalez-Vila, F.J.; Martin, F.; Sanz, J.; Alvarez-Ramis, C.; Stuchlik, L. [CSIC, Madrid (Spain). Centro de Ciencias Medioambientales

    1999-05-01

    Pyrolytic methods (standard Curie-point pyrolysis and pyrolysis in the presence of tetramethylammonium hydroxide (TMAH), followed by gas chromatography-mass spectrometry), were used to analyze the organic composition of Glyptostrobus (Taxodiaceae) remains from the Miocene deposits of Lipnica Mala (Poland), consisting of branches with their leaves. The pyrolytic analysis revealed a series of aromatic compounds with a large proportion of guaiacyl-type lignin markers (including intact C{sub 3}-methoxyphenols), and small quantities of polycyclic aromatic hydrocarbons. The alkyl compounds included fatty acid series where the C{sub 14}-C{sub 18} homologues dominated as well as additional amounts of alkanes and alkenes (maximum ca. C{sub 21}). The results suggest that lignin as well as protective epicuticular lipid polymers (including cutin and other long chain-based polyalkyl structures) selectively show the greatest degree of molecular preservation in the Glyptostrobus remains. The comparison between pyrolytic methods shows that the lignin-derived aromatic assemblages predominate in the chromatograms after conventional pyrolysis whereas thermochemolysis with TMAH leads to an `aliphatic enhancement`. This latter technique was found to be the best for analysis of the lipid signature in fossil samples with condensed polymethylene networks. 44 refs., 3 figs., 2 tabs.

  17. Combined spectroscopic and molecular docking techniques to study interaction of Zn (II) DiAmsar with serum albumins

    Energy Technology Data Exchange (ETDEWEB)

    Bardajee, Ghasem Rezanejade, E-mail: rezanejad@pnu.ac.ir; Hooshyar, Zari; Shafagh, Pegah; Ghiasvand, Samira; Kakavand, Nahaleh

    2014-12-15

    Zinc (II) diamine-sarcophagine (Zn (II) DiAmsar) as a water soluble hexadentate ligand was synthesized and characterized by nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR) and UV–visible (UV–vis) spectroscopy. The bindings of Zn (II) DiAmsar with human serum albumin (HSA) and bovine serum albumin (BSA) were investigated under the simulative physiological conditions. To study this binding, the fluorescence spectra in combination with FT-IR, UV–vis, cyclic voltammetry (CV), and molecular docking techniques were used in the present work. The results indicate that Zn (II) DiAmsar quenched effectively the intrinsic fluorescence of HSA and BSA via a static quenching process. The fluorescence quenching data was also used to determine binding sites and binding constants at different temperatures. The calculated thermodynamic parameters (∆G°, ∆H°, and ∆S°) suggest that the binding process occurs spontaneously by involving hydrogen bond and van der Waals interactions. The distance between HSA (or BSA) as a donor and Zn (II) DiAmsar as an acceptor was obtained according to fluorescence resonance energy transfer (FRET). In addition, the docking results revealed the possible binding sites and assess the microenvironment around the bounded Zn (II) DiAmsar.

  18. A new technique to improve the mechanical and biological performance of ultra high molecular weight polyethylene using a nylon coating.

    Science.gov (United States)

    Firouzi, Dariush; Youssef, Aya; Amer, Momen; Srouji, Rami; Amleh, Asma; Foucher, Daniel A; Bougherara, Habiba

    2014-04-01

    A new patent pending technique is proposed in this study to improve the mechanical and biological performance of ultra high molecular weight polyethylene (UHMWPE), i.e., to uniformly coat nylon onto the UHMWPE fiber (Firouzi et al., 2012). Mechanical tests were performed on neat and new nylon coated UHMWPE fibers to examine the tensile strength and creep resistance of the samples at different temperatures. Cytotoxicity and osteolysis induced by wear debris of the materials were investigated using (MTT) assay, and RT-PCR for tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6) osteolysis markers. Mechanical test results showed substantial improvement in maximum creep time, maximum breaking force, and toughness values of Nylon 6,6 and Nylon 6,12 coated UHMWPE fibers between average 15% and 60% at 25, 50, and 70°C. Furthermore, cytotoxicity studies have demonstrated significant improvement in cell viability using the nylon coated UHMWPE over the neat one (72.4% vs 54.8%) for 48h and (80.7 vs 5%) for 72h (PNylon 6,6 coated UHMWPE (2.5 fold increase for TNFα at 48h, and three fold increase for IL-6 at 72h (Pnylon could be used as a novel material in clinical applications with lower cytotoxicity, less wear debris-induced osteolysis, and superior mechanical properties compared to neat UHMWPE. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Study On Application Of Molecular Techniques (RAPD-PCR And RAMP-PCR) To Detect Mutation In Rice Breeding

    International Nuclear Information System (INIS)

    Hoang Thi My Linh; Phan, D. T. Son; Nguyen Thi Vang; Nguyen, T. T. Hien; Le XuanTham

    2007-01-01

    The project was carried out in 2007 with the purpose of consideration for using the two simple and inexpensive molecular techniques to estimate changes in DNA of rice mutant after gamma irradiation. Three rice cultivars: Basmati370, Tam Thom (TT1), IR64 and three gamma irradiated mutants BDS, TDS and VND 95-20 respectively, were used. Suitable DNA extraction procedure was obtained. PCR optimization was conducted on three important factors including: amount of MgCl 2 , DNA concentration and annealing temperature. 2.5 mM of MgCl 2 for RAPD-PCR and 3.75 mM for RAMP-PCR were found the best. 40 ng DNA provided a good amplification for RAMP-PCR; this figure was 50 ng for RAPD-PCR. Annealing temperatures were determined at 36 o C for RAPD primer and at 55±3 o C for Microsatellite primer. Final results showed that, both RAPD-PCR and RAMP-PCR could detect changes in DNA of rice mutants after gamma irradiation compared to their parents. Percentage of DNA changes determined by RAPD-PCR and RAMP-PCR on Basmati370 and its mutant BDS were 11.49% and 21.2% respectively; These on TT1 and TDS were 8.98% and 15.4%; and on IR64 and VND 95-20 were 3.45% and 4.95%. (author)

  20. Semi-Empirical Validation of the Cross-Band Relative Absorption Technique for the Measurement of Molecular Mixing Ratios

    Science.gov (United States)

    Pliutau, Denis; Prasad, Narasimha S

    2013-01-01

    Studies were performed to carry out semi-empirical validation of a new measurement approach we propose for molecular mixing ratios determination. The approach is based on relative measurements in bands of O2 and other molecules and as such may be best described as cross band relative absorption (CoBRA). . The current validation studies rely upon well verified and established theoretical and experimental databases, satellite data assimilations and modeling codes such as HITRAN, line-by-line radiative transfer model (LBLRTM), and the modern-era retrospective analysis for research and applications (MERRA). The approach holds promise for atmospheric mixing ratio measurements of CO2 and a variety of other molecules currently under investigation for several future satellite lidar missions. One of the advantages of the method is a significant reduction of the temperature sensitivity uncertainties which is illustrated with application to the ASCENDS mission for the measurement of CO2 mixing ratios (XCO2). Additional advantages of the method include the possibility to closely match cross-band weighting function combinations which is harder to achieve using conventional differential absorption techniques and the potential for additional corrections for water vapor and other interferences without using the data from numerical weather prediction (NWP) models.

  1. Measurements of Tilt and Focus for Sodium Beacon Adaptive Optics on the Starfire 3.5 Meter Telescope

    Science.gov (United States)

    2010-09-01

    beacon and natural guide star operation. This approach, and a more complicated approach, are described in detail by Link and Foucault [3]. They show these...Astronomical Telescopes and Instrumentation Conference, Glasgow, Scotland, 21–25 June 2004. 3. Link D. and Foucault B., "Investigation of focus control

  2. Impact of IEEE 1609.4 channel switching on the IEEE 802.11p beaconing performance

    NARCIS (Netherlands)

    van Eenennaam, Martijn; van de Venis, Anne; Karagiannis, Georgios

    2012-01-01

    The IEEE 802.11p Wireless Access in Vehicular Environment (WAVE) protocol can only transmit packets on one channel. To support multi-channel operations, channel switching procedures have been proposed in IEEE 1609.4. This paper provides an analysis of the beaconing performance of IEEE 802.11p when

  3. 75 FR 20364 - Public Buildings Service; Key Largo Beacon Annex Site; Key Largo, FL; Transfer of Property

    Science.gov (United States)

    2010-04-19

    ... GENERAL SERVICES ADMINISTRATION [Wildlife Order 187; 4-D-FL-1218] Public Buildings Service; Key Largo Beacon Annex Site; Key Largo, FL; Transfer of Property Pursuant to section 2 of Public Law 537, 80th Congress, approved May 19, 1948 (16 U.S.C. 667c), notice is hereby given that: 1. The General...

  4. Design and Practical Evaluation of a Family of Lightweight Protocols for Heterogeneous Sensing through BLE Beacons in IoT Telemetry Applications.

    Science.gov (United States)

    Hernández-Rojas, Dixys L; Fernández-Caramés, Tiago M; Fraga-Lamas, Paula; Escudero, Carlos J

    2017-12-27

    The Internet of Things (IoT) involves a wide variety of heterogeneous technologies and resource-constrained devices that interact with each other. Due to such constraints, IoT devices usually require lightweight protocols that optimize the use of resources and energy consumption. Among the different commercial IoT devices, Bluetooth and Bluetooth Low Energy (BLE)-based beacons, which broadcast periodically certain data packets to notify their presence, have experienced a remarkable growth, specially due to their application in indoor positioning systems. This article proposes a family of protocols named Lightweight Protocol for Sensors (LP4S) that provides fast responses and enables plug-and-play mechanisms that allow IoT telemetry systems to discover new nodes and to describe and auto-register the sensors and actuators connected to a beacon. Thus, three protocols are defined depending on the beacon hardware characteristics: LP4S-6 (for resource-constraint beacons), LP4S-X (for more powerful beacons) and LP4S-J (for beacons able to run complex firmware). In order to demonstrate the capabilities of the designed protocols, the most restrictive (LP4S-6) is tested after implementing it for a telemetry application in a beacon based on Eddystone (Google's open beacon format). Thus, the beacon specification is extended in order to increase its ability to manage unlimited sensors in a telemetry system without interfering in its normal operation with Eddystone frames. The performed experiments show the feasibility of the proposed solution and its superiority, in terms of latency and energy consumption, with respect to approaches based on Generic Attribute Profile (GATT) when multiple users connect to a mote or in scenarios where latency is not a restriction, but where low-energy consumption is essential.

  5. Design and Practical Evaluation of a Family of Lightweight Protocols for Heterogeneous Sensing through BLE Beacons in IoT Telemetry Applications

    Directory of Open Access Journals (Sweden)

    Dixys L. Hernández-Rojas

    2017-12-01

    Full Text Available The Internet of Things (IoT involves a wide variety of heterogeneous technologies and resource-constrained devices that interact with each other. Due to such constraints, IoT devices usually require lightweight protocols that optimize the use of resources and energy consumption. Among the different commercial IoT devices, Bluetooth and Bluetooth Low Energy (BLE-based beacons, which broadcast periodically certain data packets to notify their presence, have experienced a remarkable growth, specially due to their application in indoor positioning systems. This article proposes a family of protocols named Lightweight Protocol for Sensors (LP4S that provides fast responses and enables plug-and-play mechanisms that allow IoT telemetry systems to discover new nodes and to describe and auto-register the sensors and actuators connected to a beacon. Thus, three protocols are defined depending on the beacon hardware characteristics: LP4S-6 (for resource-constraint beacons, LP4S-X (for more powerful beacons and LP4S-J (for beacons able to run complex firmware. In order to demonstrate the capabilities of the designed protocols, the most restrictive (LP4S-6 is tested after implementing it for a telemetry application in a beacon based on Eddystone (Google’s open beacon format. Thus, the beacon specification is extended in order to increase its ability to manage unlimited sensors in a telemetry system without interfering in its normal operation with Eddystone frames. The performed experiments show the feasibility of the proposed solution and its superiority, in terms of latency and energy consumption, with respect to approaches based on Generic Attribute Profile (GATT when multiple users connect to a mote or in scenarios where latency is not a restriction, but where low-energy consumption is essential.

  6. ENVIROSUITE: USING STATE-OF-THE-ART SYNCHROTRON TECHNIQUES TO UNDERSTAND ENVIRONMENTAL REMEDIATION SCIENCE ISSUES AT THE MOLECULAR LEVEL

    International Nuclear Information System (INIS)

    FITTS, J.P.; KALB, P.D.; FRANCIS, A.J.; FUHRMANN, M.; DODGE, C.J.; GILLOW, J.B.

    2004-01-01

    Although DOE's Environmental Management program has made steady progress in cleaning up environmental legacies throughout the DOE complex, there are still significant remediation issues that remain to be solved. For example, DOE faces difficult challenges related to potential mobilization of radionuclides (e.g., actinides) and other hazardous contaminants in soils, removal and final treatment of high-level waste and residuals from leaking tanks, and the long-term stewardship of remediated sites and engineered disposal facilities, to name just a few. In some cases, new technologies and technology applications will be required based on current engineering expertise. In others, however, basic scientific research is needed to understand the mechanisms of how contaminants behave under specific conditions and how they interact with the environment, from which new engineering solutions can emerge. At Brookhaven National Laboratory (BNL) and Stony Brook University, scientists have teamed to use state-of-the-art synchrotron techniques to help understand the basic interactions of contaminants in the environment. Much of this work is conducted at the BNL National Synchrotron Light Source (NSLS), which is a user facility that provides high energy X-ray and ultraviolet photon beams to facilitate the examination of contaminants and materials at the molecular level. These studies allow us to determine how chemical speciation and structure control important parameters such as solubility, which in turn drive critical performance characteristics such as leaching. In one study for example, we are examining the effects of microbial activity on actinide contaminants under conditions anticipated at the Waste Isolation Pilot Plant. One possible outcome of this research is the identification of specific microbes that can trap uranium or other contaminants within the intracellular structure and help mitigate mobility. In another study, we are exploring the interaction of contaminants with

  7. Field and laboratory comparative evaluation of rapid malaria diagnostic tests versus traditional and molecular techniques in India

    Directory of Open Access Journals (Sweden)

    Bharti Praveen K

    2010-07-01

    Full Text Available Abstract Background Malaria presents a diagnostic challenge in most tropical countries. Microscopy remains the gold standard for diagnosing malaria infections in clinical practice and research. However, microscopy is labour intensive, requires significant skills and time, which causes therapeutic delays. The objective of obtaining result quickly from the examination of blood samples from patients with suspected malaria is now made possible with the introduction of rapid malaria diagnostic tests (RDTs. Several RDTs are available, which are fast, reliable and simple to use and can detect Plasmodium falciparum and non-falciparum infections or both. A study was conducted in tribal areas of central India to measure the overall performance of several RDTs for diagnosis of P. falciparum and non-falciparum infections in comparison with traditional and molecular techniques. Such data will be used to guide procurement decisions of policy makers and programme managers. Methods Five commercially available RDTs were tested simultaneously in field in parallel with peripheral blood smears in outbreak-affected areas. The evaluation is designed to provide comparative data on the performance of each RDT. In addition, molecular method i.e. polymerase chain reaction (PCR was also carried out to compare all three methods. Results A total of 372 patients with a clinical suspicion of malaria from Bajag Primary Health Centre (PHC of district Dindori and Satanwada PHC of district Shivpuri attending the field clinics of Regional Medical Research Centre were included in the study. The analysis revealed that the First Response Malaria Antigen pLDH/HRP2 combo test was 94.7% sensitive (95% CI 89.5-97.7 and 69.9% specific (95% CI 63.6-75.6 for P. falciparum. However, for non-falciparum infections (Plasmodium vivax the test was 84.2% sensitive (95% CI 72.1-92.5 and 96.5% specific (95% CI 93.8-98.2. The Parascreen represented a good alternative. All other RDTs were relatively

  8. Iris colour as an indicator of age feature in female Brazilian tanagers (Passeriformes: Emberizidae confirmed by a molecular sexing technique

    Directory of Open Access Journals (Sweden)

    Denise Monnerat Nogueira

    2008-12-01

    Full Text Available The Brazilian tanager, Ramphocelus bresilius is an endemic species from Brazil that is sexually dimorphic in adult plumage. Young males are similar to adult and young females until their second year. Adults and young females are not distinguishable in plumage. We tested whether iris colour can be used to separate adult females from immature females. We used for the first time the molecular sexing technique based on CHD-genes to confirm the sex of the individuals classified as "female plumage with red iris", and to identify the sex of individuals classified as "female plumage and brown iris". The adult males were used as a positive control. DNA samples from 190 individuals were analysed. The sizes of the PCR products were identified as 350 base pairs (bp for CHD-Z and 388 bp for CHD-W. We confirmed that adult females have a red iris and the young females a brown iris. We could also separate young males and females which present the same iris colour and plumage. Although there are indications that the iris colour can be used by birds to identify the adults in co-operative breeding species such as the Brazilian tanager, more behavioural data are required to understand the role of iris coloration in this species. Rev. Biol. Trop. 56 (4: 1629-1633. Epub 2008 December 12.El ave Ramphocelus bresilius es una especie endémica de Brasil con dimorfismo sexual en el plumaje del adulto. Los machos jóvenes son similares a las hembras adultas y jóvenes hasta el segundo año de vida. Adultos y hembras jóvenes son indistinguibles por el plumaje. Evaluamos si el color del iris puede ser utilizado para distinguir hembras adultas de hembras inmaduras. Utilizamos por primera vez la técnica molecular de identificación de sexos basada en los genes CHD para confirmar el género de individuos clasificados como plumaje femenino con iris rojo, y para identificar el sexo de los individuos clasificados como plumaje femenino e iris marrón. Usamos machos adultos como

  9. Studying the interaction between three synthesized heterocyclic sulfonamide compounds with hemoglobin by spectroscopy and molecular modeling techniques.

    Science.gov (United States)

    Naeeminejad, Samane; Assaran Darban, Reza; Beigoli, Sima; Saberi, Mohammad Reza; Chamani, Jamshidkhan

    2017-11-01

    The interaction between synthesized heterocyclic benzene sulfonamide compounds, N-(7-benzyl-56-biphenyl-2m-tolyl-7H-pyrrolo[23-d]pyrimidine-4-yl)-benzene sulfonamide (HBS 1 ), N-(7-benzyl-56-biphenyl-2-m-tolyl-7H-pyrrolo[23-d] pyrimidine-4-yl)-4-methyl- benzene sulfonamide (HBS 2 ), and N-(7-benzyl-56-biphenyl-2-m-tolyl-7H-pyrrolo[23-d]pyrimidine-4-yl)-4-chloro-benzene sulfonamide (HBS 3 ) with Hb was studied by fluorescence quenching, zeta potentional, circular dichroism, and molecular modeling techniques. The fluorescence spectroscopy experiments were performed in order to study the conformational changes, possibly due to a discrete reorganization of Trp residues during binding between HBS derivatives and Hb. The variation of the K SV value suggested that hydrophobic and electrostatic interactions were the predominant intermolecular forces stabilizing the complex. The K SV1 ans K SV2 values of HBS derivatives with Hb are .6 × 10 13 and 3 × 10 13  M -1 for Hb-HBS 1 , 1 × 10 13 and 4 × 10 13  M -1 for Hb-HBS 2 , .9 × 10 13 , and 6 × 10 13  M -1 for Hb-HBS 3 , respectively. The molecular distances between Hb and HBS derivatives in binary and ternary systems were estimated according to Förster's theory of dipole-dipole non-radiation energy transfer. The quantitative analysis data of circular dichroism spectra demonstrated that the binding of the three HBS derivatives to Hb induced conformational changes in Hb. Changes in the zeta potential of the Hb-HBS derivatives complexes demonstrated a hydrophobic adsorption of the anionic ligand onto the surface of Hb as well as both electrostatic and hydrophobic adsorption in the case of the complex. The modeling data thus confirmed the experimental results. This study is expected to provide important insight into the interaction of Hb with three HBS derivatives to use in various toxicological and therapeutic processes.

  10. Identification of microorganisms involved in nitrogen removal from wastewater treatment systems by means of molecular biology techniques; Identificacion de microorganismos implicados en la eliminacion de nitrogeno en sistemas de tratamiento de aguas residuales mediante tecnicas de biologia molecular

    Energy Technology Data Exchange (ETDEWEB)

    Figueroa, M.; Alonso-Gutierrez, J.; Campos, J. L.; Mendez, R.; Mosquera-Corral, A.

    2010-07-01

    The identification of the main bacteria populations present in the granular biomass from a biological reactor treating wastewater has been performed by applying two different molecular biology techniques. By means of the DGGE technique five different genera of heterotrophic bacteria (Thiothrix, Thauera, Cloroflexi, Comamanas y Zoogloea) and one of ammonia oxidizing bacteria (Nitrosomanas) were identified. The FISH technique, based on microscopy, allowed the in situ visualization and quantification of those microorganisms. Special attention was paid to filamentous bacteria distribution (Thiothrix and Cloroflexi) which could exert a structural function in aerobic granular sludge. (Author) 26 refs.

  11. Using non-invasive molecular spectroscopic techniques to detect unique aspects of protein Amide functional groups and chemical properties of modeled forage from different sourced-origins

    Science.gov (United States)

    Ji, Cuiying; Zhang, Xuewei; Yu, Peiqiang

    2016-03-01

    The non-invasive molecular spectroscopic technique-FT/IR is capable to detect the molecular structure spectral features that are associated with biological, nutritional and biodegradation functions. However, to date, few researches have been conducted to use these non-invasive molecular spectroscopic techniques to study forage internal protein structures associated with biodegradation and biological functions. The objectives of this study were to detect unique aspects and association of protein Amide functional groups in terms of protein Amide I and II spectral profiles and chemical properties in the alfalfa forage (Medicago sativa L.) from different sourced-origins. In this study, alfalfa hay with two different origins was used as modeled forage for molecular structure and chemical property study. In each forage origin, five to seven sources were analyzed. The molecular spectral profiles were determined using FT/IR non-invasive molecular spectroscopy. The parameters of protein spectral profiles included functional groups of Amide I, Amide II and Amide I to II ratio. The results show that the modeled forage Amide I and Amide II were centered at 1653 cm- 1 and 1545 cm- 1, respectively. The Amide I spectral height and area intensities were from 0.02 to 0.03 and 2.67 to 3.36 AI, respectively. The Amide II spectral height and area intensities were from 0.01 to 0.02 and 0.71 to 0.93 AI, respectively. The Amide I to II spectral peak height and area ratios were from 1.86 to 1.88 and 3.68 to 3.79, respectively. Our results show that the non-invasive molecular spectroscopic techniques are capable to detect forage internal protein structure features which are associated with forage chemical properties.

  12. Widespread, Juvenile Alteration of the Ferrar Dolerite in Beacon Valley, Antarctica

    Science.gov (United States)

    Salvatore, M. R.; Mustard, J. F.; Head, J. W.; Cooper, R. F.; Marchant, D. R.

    2011-12-01

    The hyper-arid and hypo-thermal conditions that are pervasive throughout the McMurdo Dry Valleys (MDV) result in slow, immature chemical alteration that is often shadowed by physical erosion and mass wasting processes. Beacon Valley is an exception to this model in that its surface is extremely stable and has been for at least several million years. This stability allows for chemical alteration to progress in the absence of extensive physical erosion. We have collected fourteen Ferrar Dolerite samples from the floor of central Beacon Valley and have analyzed them to assess the range and extent of chemical and mineralogical variations between the unaltered interiors and their altered surfaces. Surface rocks from Beacon Valley, Antarctica, exhibit a distinct red/brown weathering/alteration rind relative to their dark grey interiors as a result of in situ chemical alteration. The rind is readily visible in broken and cut rocks and is typically 0.5-10 mm in thickness. It shows a gradational transition to the unaltered interiors. Reflectance and emission spectroscopy both show distinct disparity between unaltered rock interiors and their corresponding surfaces related to the alteration rind. Interestingly, spectroscopic signatures of primary minerals are clearly present showing that the alteration process does not completely mask the primary rock constituents from remote sensing. Visible-near infrared spectra show distinct ferric absorptions between 0.3 and 1.0 μm indicating a significant increase in ferric iron. Emission spectroscopy shows distinct absorptions related to poorly crystalline alteration products suggesting a breakdown in mineral structure in the optically active zone. EPMA analyses and BSE imagery of the dolerite surfaces and the transition between altered and unaltered regions, however, do not show any obvious chemical or mineralogical variability. This result is supported by flux fusion and ICP-AES analyses that show no substantial chemical variations

  13. Model-Based Localization and Tracking Using Bluetooth Low-Energy Beacons

    Directory of Open Access Journals (Sweden)

    F. Serhan Daniş

    2017-10-01

    Full Text Available We introduce a high precision localization and tracking method that makes use of cheap Bluetooth low-energy (BLE beacons only. We track the position of a moving sensor by integrating highly unreliable and noisy BLE observations streaming from multiple locations. A novel aspect of our approach is the development of an observation model, specifically tailored for received signal strength indicator (RSSI fingerprints: a combination based on the optimal transport model of Wasserstein distance. The tracking results of the entire system are compared with alternative baseline estimation methods, such as nearest neighboring fingerprints and an artificial neural network. Our results show that highly accurate estimation from noisy Bluetooth data is practically feasible with an observation model based on Wasserstein distance interpolation combined with the sequential Monte Carlo (SMC method for tracking.

  14. Model-Based Localization and Tracking Using Bluetooth Low-Energy Beacons.

    Science.gov (United States)

    Daniş, F Serhan; Cemgil, Ali Taylan

    2017-10-29

    We introduce a high precision localization and tracking method that makes use of cheap Bluetooth low-energy (BLE) beacons only. We track the position of a moving sensor by integrating highly unreliable and noisy BLE observations streaming from multiple locations. A novel aspect of our approach is the development of an observation model, specifically tailored for received signal strength indicator (RSSI) fingerprints: a combination based on the optimal transport model of Wasserstein distance. The tracking results of the entire system are compared with alternative baseline estimation methods, such as nearest neighboring fingerprints and an artificial neural network. Our results show that highly accurate estimation from noisy Bluetooth data is practically feasible with an observation model based on Wasserstein distance interpolation combined with the sequential Monte Carlo (SMC) method for tracking.

  15. Efficiency of rep-PCR fingerprinting as a useful technique for molecular typing of plant pathogenic fungal species: Botryosphaeriaceae species as a case study.

    Science.gov (United States)

    Abdollahzadeh, Jafar; Zolfaghari, Sajedeh

    2014-12-01

    Progress in molecular biology and the advent of rapid and accurate molecular techniques have contributed to precise and rapid detection and differentiation of microbial pathogens. Identification of the Botryosphaeriaceae species based on morphology has been problematic over time. In this study, we used rep-PCR technique as a molecular tool for typing and differentiation of the Botryosphaeriaceae species, well-known and cosmopolitan fungal pathogens on woody plants. Three primer sets BOX, ERIC and REP were used to differentiate 27 species belong to eight genera. The majority of them were examined in terms of typing and differentiation using molecular methods for the first time. All the primer sets were able to generate species-specific DNA fingerprints from all the tested strains, with two exceptions in the genera Diplodia and Spencermartinsia. Despite the deficiency of each primer sets to separate a few species, cluster analysis of combined data sets indicated the ability of rep-PCR technique to separate 26 out of 27 examined species in highly supported clusters corresponded to the species recognized based on DNA sequence data. Our findings revealed the efficiency of rep-PCR for detection and differentiation of the Botryosphaeriaceae species, especially cryptic species with the same ITS sequences and similar morphology. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  16. MO-FG-BRA-06: Electromagnetic Beacon Insertion in Lung Cancer Patients and Resultant Surrogacy Errors for Dynamic MLC Tumour Tracking

    International Nuclear Information System (INIS)

    Hardcastle, N; Booth, J; Caillet, V; Haddad, C; Crasta, C; O’Brien, R; Keall, P; Szymura, K

    2016-01-01

    Purpose: To assess endo-bronchial electromagnetic beacon insertion and to quantify the geometric accuracy of using beacons as a surrogate for tumour motion in real-time multileaf collimator (MLC) tracking of lung tumours. Methods: The LIGHT SABR trial is a world-first clinical trial in which the MLC leaves move with lung tumours in real time on a standard linear accelerator. Tracking is performed based on implanted electromagnetic beacons (CalypsoTM, Varian Medical Systems, USA) as a surrogate for tumour motion. Five patients have been treated and have each had three beacons implanted endo-bronchially under fluoroscopic guidance. The centre of mass (C.O.M) has been used to adapt the MLC in real-time. The geometric error in using the beacon C.O.M as a surrogate for tumour motion was measured by measuring the tumour and beacon C.O.M in all phases of the respiratory cycle of a 4DCT. The surrogacy error was defined as the difference in beacon and tumour C.O.M relative to the reference phase (maximum exhale). Results: All five patients have had three beacons successfully implanted with no migration between simulation and end of treatment. Beacon placement relative to tumour C.O.M varied from 14 to 74 mm and in one patient spanned two lobes. Surrogacy error was measured in each patient on the simulation 4DCT and ranged from 0 to 3 mm. Surrogacy error as measured on 4DCT was subject to artefacts in mid-ventilation phases. Surrogacy error was a function of breathing phase and was typically larger at maximum inhale. Conclusion: Beacon placement and thus surrogacy error is a major component of geometric uncertainty in MLC tracking of lung tumours. Surrogacy error must be measured on each patient and incorporated into margin calculation. Reduction of surrogacy error is limited by airway anatomy, however should be taken into consideration when performing beacon insertion and planning. This research is funded by Varian Medical Systems via a collaborative research agreement.

  17. Investigation of the Lobular Carcinoma in Situ, Using Molecular Genetic Techniques, for the Involvement of Novel Genes

    National Research Council Canada - National Science Library

    Mastracci, Teresa L; Andrulis, Irene L

    2005-01-01

    .... Our study proposes to investigate LN lesions, lacking any adjacent invasive carcinoma, for alterations in and expression of known and novel genes/proteins with the goal of characterizing a molecular genetic profile...

  18. Dengue virus type 4 in Niterói, Rio de Janeiro: the role of molecular techniques in laboratory diagnosis and entomological surveillance.

    Science.gov (United States)

    Castro, Márcia Gonçalves de; Nogueira, Rita Maria Ribeiro; Filippis, Ana Maria Bispo de; Ferreira, Anielly Alves; Lima, Monique da Rocha Queiroz; Faria, Nieli Rodrigues da Costa; Nogueira, Fernanda de Bruycker; Simões, Jaqueline Bastos Santos; Nunes, Priscila Conrado Guerra; Sampaio, Simone Alves; Lourenço-de-Oliveira, Ricardo; Santos, Flávia Barreto dos

    2012-11-01

    In Niterói, state of Rio de Janeiro, dengue virus type 4 (DENV-4) was isolated for the first time in March 2011. We analysed the laboratory findings of the first cases and evaluated the use of molecular techniques for the detection of DENV-4 in Aedes aegypti that were field-caught. Conventional reverse transcriptase-polymerase chain reaction (RT-PCR) and Simplexa™ Dengue real-time RT-PCR confirmed DENV-4 infection in all cases. Additionally, DENV-4 was confirmed in a female Ae. aegypti with 1.08 x 10(3) copies/mL of virus, as determined by quantitative real-time RT-PCR. This is the first time the Simplexa™ Dengue real-time assay has been used for the classification of cases of infection and for entomological investigations. The use of these molecular techniques was shown to be important for the surveillance of dengue in humans and vectors.

  19. Design of a K/Q-Band Beacon Receiver for the Alphasat Technology Demonstration Payload (TDP) #5 Experiment

    Science.gov (United States)

    Morse, Jacquelynne R.

    2014-01-01

    This paper describes the design and performance of a coherent KQ-band (2040 GHz) beacon receiver developed at NASA Glenn Research Center (GRC) that will be installed at the Politecnico di Milano (POLIMI) for use in the Alphasat Technology Demonstration Payload 5 (TDP5) beacon experiment. The goal of this experiment is to characterize rain fade attenuation at 40 GHz to improve the performance of existing statistical rain attenuation models in the Q-band. The ground terminal developed by NASA GRC utilizes an FFT-based frequency estimation receiver capable of characterizing total path attenuation effects due to gaseous absorption, clouds, rain, and scintillation. The receiver system has been characterized in the lab and demonstrates a system dynamic range performance of better than 58 dB at 1 Hz and better than 48 dB at 10 Hz rates.

  20. Quality control of reared parasitoids:preliminary study on the application of RAPD Molecular Marker technique to the model Opius concolor.

    OpenAIRE

    SFEIR, Thérèse

    2003-01-01

    The evaluation of field efficiency of reared Opius concolor released to control the olive fly, in the presence of indigenous populations interfering with release results becomes unreliable. RAPD (Random Amplified Polymorphic DNA) molecular marker technique was proposed to differentiate between indigenous and reared populations.Indigenous samples were collected from several regions in Puglia-Basilicata-Sardinia. Reared populations were brought from the insectarium of Cagliari-Sardinia .The ini...

  1. Image analysis, methanogenic activity measurements, and molecular biological techniques to monitor granular sludge from an EGSB reactor fed with oleic acid

    OpenAIRE

    Pereira, M. A.; Roest, K.; Stams, Alfons Johannes Maria; Akkermans, A. D. L.; Amaral, A. L.; Pons, M. N.; Ferreira, E. C.; Mota, M.; Alves, M. M.

    2003-01-01

    Morphological changes in anaerobic granular sludge fed with increasing loads of oleic acid were quantified by image analysis. The combination of this technique with data on the accumulation of adsorbed long chain fatty acid and with the molecular characterization of microbial community gave insight into the mechanisms of sludge disintegration, flotation and washout. It was found that the bacterial domain was more affected than the archaeal domain during this process. However, no acetoclastic ...

  2. Aspect Determination Using a Beacon with a Spiral Wave Front: Modeling and Performance Analysis in Operational Environments

    Science.gov (United States)

    2014-12-19

    the NSWC PCD Acoustic Test Facility in FY10 and at the Navy’s Dodge Pond facility operated by the Naval Undersea Warfare Center–Division Newport...minima shown in Fig. 15. The choice of minima will depend on the signal processing requirements of the beacon receiver, either mini - mizing the phase...surface it is also moving over these rods, leading to variation in amplitude. To mini - mize these effects, a sliding average is applied to the data

  3. 3M™ Molecular detection system versus MALDI-TOF mass spectrometry and molecular techniques for the identification of Escherichia coli 0157:H7, Salmonella spp. &Listeria spp.

    Science.gov (United States)

    Loff, Marché; Mare, Louise; de Kwaadsteniet, Michele; Khan, Wesaal

    2014-06-01

    The aim of this study was to compare standard selective plating, conventional PCR (16S rRNA and species specific primers), MALDI-TOF MS and the 3M™ Molecular Detection System for the routine detection of the pathogens Listeria, Salmonella and Escherichia coli 0157:H7 in wastewater and river water samples. MALDI-TOF MS was able to positively identify 20/21 (95%) of the E. coli isolates obtained at genus and species level, while 16S rRNA sequencing only correctly identified 6/21 (28%) as E. coli strains. None of the presumptive positive Listeria spp. and Salmonella spp. isolates obtained by culturing on selective media were positively identified by MALDI-TOF and 16S rRNA analysis. The species-specific E. coli 0157:H7 PCR described in this present study, was not able to detect any E. coli 0157:H7 strains in the wastewater and river water samples analysed. However, E. coli strains, Listeria spp., L. monocytogenes and Salmonella spp. were detected using species specific PCR. Escherichia coli 0157:H7, Listeria spp. and Salmonella spp. were also sporadically detected throughout the sampling period in the wastewater and river water samples analysed by the 3M™ Molecular Detection System. MALDI-TOF MS, which is a simple, accurate and cost-effective detection method, efficiently identified the culturable organisms, while in the current study both species specific PCR (Listeria spp. and Salmonella spp.) and 3M™ Molecular Detection System could be utilised for the direct routine analysis of pathogens in water sources. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. A case study of pediatric asthma alerts from the beacon community program in cincinnati: technology is just the first step.

    Science.gov (United States)

    Trudnak, Tara; Mansour, Mona; Mandel, Keith; Sauers, Hadley; Pandzik, Gerry; Donisi, Carl; Fairbrother, Gerry

    2014-01-01

    The Beacon Community in Cincinnati, Ohio was an innovative, community-wide initiative to use technology to transform care. One important feature was the development of regional alerts to notify practices when patients were hospitalized or seen in the emergency department. The purpose of this paper is to describe the way in which technology engages the improvement process, and to describe the early stages of learning how to use technology to enhance quality improvement. We interviewed key Beacon leaders as well as providers and office staff in selected practices. We also collected preliminary data from practices that reflected handling of alerts, including the number of asthma related alerts received and followed up. Regional alerts, supplied by the community-wide health information exchange, were a significant addition to the quality improvement effort in that they enabled practices to identify and follow up with additional children at risk. An important finding was the substantial effort at the practice level to integrate technology into ongoing patient care. Developing the technology for community wide alerts represented a significant endeavor in the Cincinnati Beacon Community. However, the technology was just the first step. Despite extra effort and time required on the part of individual practices, they reported that the value of having alerts was high. Hospital and ED visits represent some of the most costly aspects of care, and an efficient process for intervening with children using these costly services was seen as of significant value.

  5. Application of the rotating ring-disc-electrode technique to water oxidation by surface-bound molecular catalysts.

    Science.gov (United States)

    Concepcion, Javier J; Binstead, Robert A; Alibabaei, Leila; Meyer, Thomas J

    2013-10-07

    We report here the application of a simple hydrodynamic technique, linear sweep voltammetry with a modified rotating-ring-disc electrode, for the study of water oxidation catalysis. With this technique, we have been able to reliably obtain turnover frequencies, overpotentials, Faradaic conversion efficiencies, and mechanistic information from single samples of surface-bound metal complex catalysts.

  6. Learning from health information exchange technical architecture and implementation in seven beacon communities.

    Science.gov (United States)

    McCarthy, Douglas B; Propp, Karen; Cohen, Alexander; Sabharwal, Raj; Schachter, Abigail A; Rein, Alison L

    2014-01-01

    As health care providers adopt and make "meaningful use" of health information technology (health IT), communities and delivery systems must set up the infrastructure to facilitate health information exchange (HIE) between providers and numerous other stakeholders who have a role in supporting health and care. By facilitating better communication and coordination between providers, HIE has the potential to improve clinical decision-making and continuity of care, while reducing unnecessary use of services. When implemented as part of a broader strategy for health care delivery system and payment reform, HIE capability also can enable the use of analytic tools needed for population health management, patient engagement in care, and continuous learning and improvement. The diverse experiences of seven communities that participated in the three-year federal Beacon Community Program offer practical insight into factors influencing the technical architecture of exchange infrastructure and its role in supporting improved care, reduced cost, and a healthier population. The case studies also document challenges faced by the communities, such as significant time and resources required to harmonize variations in the interpretation of data standards. Findings indicate that their progress developing community-based HIE strategies, while driven by local needs and objectives, is also influenced by broader legal, policy, and market conditions.

  7. Space Weather Operation at KASI With Van Allen Probes Beacon Signals

    Science.gov (United States)

    Lee, Jongkil; Kim, Kyung-Chan; Giuseppe, Romeo; Ukhorskiy, Sasha; Sibeck, David; Kessel, Ramona; Mauk, Barry; Giles, Barbara; Gu, Bon-Jun; Lee, Hyesook; Park, Young-Deuk; Lee, Jaejin

    2018-02-01

    The Van Allen Probes (VAPs) are the only modern National Aeronautics and Space Administration (NASA) spacecraft broadcasting real-time data on the Earth's radiation belts for space weather operations. Since 2012, the Korea Astronomy and Space Science Institute (KASI) has contributed to the receipt of these data via a 7 m satellite-tracking antenna and used these beacon data for space weather operations. An approximately 15 min period is required from measurement to acquisition of Level-1 data. In this paper, we demonstrate the use of VAP data for monitoring space weather conditions at geostationary orbit (GEO) by highlighting the Saint Patrick's Day storm of 2015. During that storm, Probe-A observed a significant increase in the relativistic electron flux at 3 RE. Those electrons diffused outward resulting in a large increase of the electron flux >2 MeV at GEO, which potentially threatened satellite operations. Based on this study, we conclude that the combination of VAP data and National Oceanic and Atmospheric Administration-Geostationary Operational Environmental Satellite (NOAA-GOES) data can provide improved space environment information to geostationary satellite operators. In addition, the findings obtained indicate that more data-receiving sites would be necessary and data connections improved if this or a similar system were to be used as an operational data service.

  8. The keys to governance and stakeholder engagement: the southeast michigan beacon community case study.

    Science.gov (United States)

    Des Jardins, Terrisca R

    2014-01-01

    Community-based health information exchanges (HIEs) and efforts to consolidate and house data are growing, given the advent of Accountable Care Organizations (ACOs) under the Affordable Care Act and other similar population health focused initiatives. The Southeast Michigan Beacon Community (SEMBC) can be looked to as one case study that offers lessons learned, insights on challenges faced and accompanying workarounds related to governance and stakeholder engagement. The SEMBC case study employs an established Data Warehouse Governance Framework to identify and explain the necessary governance and stakeholder engagement components, particularly as they relate to community-wide data sharing and data warehouses or repositories. Perhaps the biggest lesson learned through the SEMBC experience is that community-based work is hard. It requires a great deal of community leadership, collaboration and resources. SEMBC found that organizational structure and guiding principles needed to be continually revisited and nurtured in order to build the relationships and trust needed among stakeholder organizations. SEMBC also found that risks and risk mitigation tactics presented challenges and opportunities at the outset and through the duration of the three year pilot period. Other communities across the country embarking on similar efforts need to consider realistic expectations about community data sharing infrastructures and the accompanying and necessary governance and stakeholder engagement fundamentals.

  9. The Inversion of Ionospheric/plasmaspheric Electron Density From GPS Beacon Observations

    Science.gov (United States)

    Zou, Y. H.; Xu, J. S.; Ma, S. Y.

    It is a space-time 4-D tomography to reconstruct ionospheric/ plasmaspheric elec- tron density, Ne, from ground-based GPS beacon measurements. The mathematical foundation of such inversion is studied in this paper and some simulation results of reconstruction for GPS network observation are presented. Assuming reasonably a power law dependence of NE on time with an index number of 1-3 during one ob- servational time of GPS (60-90min.), 4-D inversion in consideration is reduced to a 3-D cone-beam tomography with incomplete projections. To see clearly the effects of the incompleteness on the quality of reconstruction for 3-D condition, we deduced theoretically the formulae of 3-D parallel-beam tomography. After establishing the mathematical basis, we adopt linear temporal dependence of NE and voxel elemental functions to perform simulation of NE reconstruction with the help of IRI90 model. Reasonable time-dependent 3-D images of ionosphere/ plasmasphere electron density distributions are obtained when taking proper layout of the GPS network and allowing variable resolutions in vertical.

  10. Outage Probability Analysis in Power-Beacon Assisted Energy Harvesting Cognitive Relay Wireless Networks

    Directory of Open Access Journals (Sweden)

    Ngoc Phuc Le

    2017-01-01

    Full Text Available We study the performance of the secondary relay system in a power-beacon (PB assisted energy harvesting cognitive relay wireless network. In our system model, a secondary source node and a relay node first harvest energy from distributed PBs. Then, the source node transmits its data to the destination node with the help of the relay node. Also, fading coefficients of the links from the PBs to the source node and relay node are assumed independent but not necessarily identically distributed (i.n.i.d Nakagami-m random variables. We derive exact expressions for the power outage probability and the channel outage probability. Based on that, we analyze the total outage probability of the secondary relay system. Asymptotic analysis is also performed, which provides insights into the system behavior. Moreover, we evaluate impacts of the primary network on the performance of the secondary network with respect to the tolerant interference threshold at the primary receiver as well as the interference introduced by the primary transmitter at the secondary source and relay nodes. Simulation results are provided to validate the analysis.

  11. Alimentary tract bacteria isolated and identified with API-20E and molecular cloning techniques from Australian tropical fruit flies, Bactrocera cacuminata and B. tryoni.

    Science.gov (United States)

    Thaochan, N; Drew, R A I; Hughes, J M; Vijaysegaran, S; Chinajariyawong, A

    2010-01-01

    Bacteria were isolated from the crop and midgut of field collected Bactrocera cacuminata (Hering) and Bactrocera tryoni (Froggatt) (Diptera: Tephritidae). Two methods were used, firstly isolation onto two types of bacteriological culture media (PYEA and TSA) and identification using the API-20E diagnostic kit, and secondly, analysis of samples using the 16S rRNA gene molecular diagnostic method. Using the API-20E method, 10 genera and 17 species of bacteria in the family Enterobacteriaceae were identified from cultures growing on the nutrient agar. The dominant species in both the crop and midgut were Citrobacter freundii, Enterobacter cloacae and Klebsiella oxytoca. Providencia rettgeri, Klebsiella pneumoniae ssp ozaenae and Serratia marcescens were isolated from B. tryoni only. Using the molecular cloning technique that is based on 16S rRNA gene sequences, five bacteria classes were dignosed — Alpha-, Beta-, Gamma- and Delta- Proteobacteria and Firmicutes — including five families, Leuconostocaceae, Enterococcaceae, Acetobacteriaceae, Comamonadaceae and Enterobacteriaceae. The bacteria affiliated with Firmicutes were found mainly in the crop while the Gammaproteobacteria, especially the family Enterobacteriaceae, was dominant in the midgut. This paper presents results from the first known application of molecular cloning techniques to study bacteria within tephritid species and the first record of Firmicutes bacteria in these flies.

  12. Molecular Biology: Conference on Genetic Engineering Techniques (2nd) Held in London (United Kingdom) on 20-21 November 1986.

    Science.gov (United States)

    1987-05-27

    A181 T5 MOLECULAR BIOLOGY CONFERENCE O GENETIC ENGINEERING 1/ TECNIQUES (2ND) HEL (U) OFFICE OF NAVAL RESEARCH LONDON (ENGLAND) C F ZOMZELY-NEURATH...represented both genetic diseases. For example, Hunting- academic and industrial organizations in ton’s Chorea, Cystic Fibrosis , and a 1:1 ratio...be cloned in available vicinity of the Huntington’s Chorea and vectors or easily analyzed by standard Cystic Fibrosis mutations in human, and 3

  13. Towards mosquito sterile insect technique programmes: Exploring genetic, molecular, mechanical and behavioural methods of sex separation in mosquitoes

    Czech Academy of Sciences Publication Activity Database

    Gilles, J. R. L.; Schetelig, M. F.; Scolari, F.; Marec, František; Capurro, M.L.; Franz, G.; Bourtzis, K.

    132S, č. 1 (2014), S178-S187 ISSN 0001-706X R&D Projects: GA ČR GA523/09/2106 Grant - others:Deutsche Forschungsgemeinschalft(DE) SCHE 1833/1 Institutional support: RVO:60077344 Keywords : female elimination * vector control * genetic sexing strains (GSS) Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.270, year: 2014 http://www.sciencedirect.com/science/article/pii/S0001706X13002209?via=ihub

  14. Nanomechanical molecular devices made of DNA origami.

    Science.gov (United States)

    Kuzuya, Akinori; Ohya, Yuichi

    2014-06-17

    CONSPECTUS: Eight years have passed since the striking debut of the DNA origami technique ( Rothemund, P. W. K. Nature 2006 , 440 , 297 - 302 ), in which long single-stranded DNA is folded into a designed nanostructure, in either 2D or 3D, with the aid of many short staple strands. The number of proposals for new design principles for DNA origami structures seems to have already reached a peak. It is apparent that DNA origami study is now entering the second phase of creating practical applications. The development of functional nanomechanical molecular devices using the DNA origami technique is one such application attracting significant interest from researchers in the field. Nanomechanical DNA origami devices, which maintain the characteristics of DNA origami structures, have various advantages over conventional DNA nanomachines. Comparatively high assembly yield, relatively large size visible via atomic force microscopy (AFM) or transmission electron microscopy (TEM), and the capability to assemble multiple functional groups with precision using multiple staple strands are some of the advantages of the DNA origami technique for constructing sophisticated molecular devices. This Account describes the recent developments of such nanomechanical DNA origami devices and reviews the emerging target of DNA origami studies. First, simple "dynamic" DNA origami structures with transformation capability, such as DNA origami boxes and a DNA origami hatch with structure control, are briefly summarized. More elaborate nanomechanical DNA origami devices are then reviewed. The first example describes DNA origami pinching devices that can be used as "single-molecule" beacons to detect a variety of biorelated molecules, from metal ions at the size of a few tens of atomic mass number units to relatively gigantic proteins with a molecular mass greater than a hundred kilodaltons, all on a single platform. Clamshell-like DNA nanorobots equipped with logic gates can discriminate

  15. Sensorial, biochemical and molecular changes in Raboso Piave grape berries applying "Double Maturation Raisonnée" and late harvest techniques.

    Science.gov (United States)

    Corso, Massimiliano; Ziliotto, Fiorenza; Rizzini, Fabio M; Teo, Gianni; Cargnello, Giovanni; Bonghi, Claudio

    2013-07-01

    At ripening, Vitis vinifera cv Raboso Piave grapes have high acidity, which results in an astringent wine that is not easy to drink. To overcome this limitation, several researches have attempted to alter the polyphenols profile mainly by applying different harvest techniques. The aim of this work was to investigate sensorial, biochemical, and molecular changes in Raboso Piave grape berries subjected to delayed harvests as Late Harvest (LH) and "Double Maturation Raisonnée" (DMR) techniques. At the molecular level, a microarray study was conducted comparing Traditional Harvest berries (TH) to LH and DMR ones. Gene ontology enrichment analysis pointed out that LH and DMR techniques affected metabolism of acids, sugars and polyphenols. A Principal Component Analysis, performed on transcriptomic data, pointed out that malate catabolism as well as some branches of flavonoids biosynthesis are significantly affected by DMR. In DMR grape berries, the flavonol and catechin accumulations were induced and depressed, respectively. In parallel, the transcription of flavonol synthase and leucoanthocyanidin-reductase 2, the main genes responsible for flavonol and catechin biosynthesis, were similarly induced and down-regulated. These changes resulted in a brighter colored wine with lower astringency. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  16. Complex polarimetric and spectral techniques in diagnostics of blood plasma of patients with ovarian cancer as a preliminary stage molecular genetic screening

    Science.gov (United States)

    Grzegorzewski, B.; Peresunko, O. P.; Yermolenko, S. B.

    2018-01-01

    This work is devoted to the substantiation and selection of patients with ovarian cancer (OC) for the purpose of conducting expensive molecular genetic studies on genotyping. As diagnostic methods have been used ultraviolet spectrometry samples of blood plasma in the liquid state, infrared spectroscopy middle range (2,5 - 25 microns) dry residue of plasma polarization and laser diagnostic technique of thin histological sections of biological tissues. Obtained results showed that the use of spectrophotometry in the range of 1000-3000 cm-1 allowed to establish quantitative parameters of the plasma absorption rate of blood of patients in the third group in different ranges, which would allow in the future to conduct an express analysis of the patient's condition (procedure screening) for further molecular-genetic typing on BRCA I and II.

  17. Image analysis, methanogenic activity measurements, and molecular biological techniques to monitor granular sludge from an EGSB reactor fed with oleic acid.

    Science.gov (United States)

    Pereira, M A; Roest, K; Stams, A J M; Akkermans, A D L; Amaral, A L; Pons, M N; Ferreira, E C; Mota, M; Alves, M M

    2003-01-01

    Morphological changes in anaerobic granular sludge fed with increasing loads of oleic acid were quantified by image analysis. The combination of this technique with data on the accumulation of adsorbed long chain fatty acid and with the molecular characterization of microbial community gave insight into the mechanisms of sludge disintegration, flotation and washout. It was found that the bacterial domain was more affected than the archaeal domain during this process. However, no acetoclastic activity and onlya residual hydrogenotrophic activity were detected in the sludge at the end of the operation.

  18. New PCR test for detection of Candida glabrata based on the molecular target chosen by the RAPD technique.

    Science.gov (United States)

    Olchawa, Anna; Krawczyk, Beata; Brillowska-Dabrowska, Anna

    2013-01-01

    Rapid, reliable diagnosis is a necessary condition for the successful treatment of infections. Such diagnostic assays are continually being developed. The paper presents a method for selecting the molecular target for PCR-based diagnostics based on the comparison of RAPD patterns. A sequence encoding Candida glabrata CBS138 hypothetical protein was selected. The limit of detection for PCR and real-time PCR reactions with DNA extracted from blood samples spiked with Candida glabrata was estimated at 1 CFU/ml. The application of the assays developed in this study would thus seem to be promising as a complementary method in the diagnostics of C. glabrata infections.

  19. An evaluation of the PCR-RFLP technique to aid molecular-based monitoring of felids and canids in India

    Directory of Open Access Journals (Sweden)

    Home Chandrima

    2010-06-01

    Full Text Available Abstract Background The order Carnivora is well represented in India, with 58 of the 250 species found globally, occurring here. However, small carnivores figure very poorly in research and conservation policies in India. This is mainly due to the dearth of tested and standardized techniques that are both cost effective and conducive to small carnivore studies in the field. In this paper we present a non-invasive genetic technique standardized for the study of Indian felids and canids with the use of PCR amplification and restriction enzyme digestion of scat collected in the field. Findings Using existing sequences of felids and canids from GenBank, we designed primers from the 16S rRNA region of the mitochondrial genome and tested these on ten species of felids and five canids. We selected restriction enzymes that would cut the selected region differentially for various species within each family. We produced a restriction digestion profile for the potential differentiation of species based on fragment patterns. To test our technique, we used felid PCR primers on scats collected from various habitats in India, representing varied environmental conditions. Amplification success with field collected scats was 52%, while 86% of the products used for restriction digestion could be accurately assigned to species. We verified this through sequencing. A comparison of costs across the various techniques currently used for scat assignment showed that this technique was the most practical and cost effective. Conclusions The species-specific key developed in this paper provides a means for detailed investigations in the future that focus on elusive carnivores in India and this approach provides a model for other studies in areas of Asia where many small carnivores co-occur.

  20. Experimental Analysis of Sublimation Dynamics for Buried Glacier Ice in Beacon Valley, Antarctica

    Science.gov (United States)

    Ehrenfeucht, S.; Dennis, D. P.; Marchant, D. R.

    2017-12-01

    The age of the oldest known buried ice in Beacon Valley, McMurdo Dry Valleys (MDV) Antarctica is a topic of active debate due to its implications for the stability of the East Antarctic Ice Sheet. Published age estimates range from as young as 300 ka to as old as 8.1 Ma. In the upland MDV, ablation occurs predominantly via sublimation. The relict ice in question (ancient ice from Taylor Glacier) lies buried beneath a thin ( 30-70 cm) layer of sublimation till, which forms as a lag deposit as underlying debris-rich ice sublimes. As the ice sublimates, the debris held within the ice accumulates slowly on the surface, creating a porous boundary between the buried-ice surface and the atmosphere, which in turn influences gas exchange between the ice and the atmosphere. Additionally, englacial debris adds several salt species that are ultimately concentrated on the ice surface. It is well documented the rate of ice sublimation varies as a function of overlying till thickness. However, the rate-limiting dynamics under varying environmental conditions, including the threshold thicknesses at which sublimation is strongly retarded, are not yet defined. To better understand the relationships between sublimation rate, till thickness, and long-term surface evolution, we build on previous studies by Lamp and Marchant (2017) and evaluate the role of till thickness as a control on ice loss in an environmental chamber capable of replicating the extreme cold desert conditions observed in the MDV. Previous work has shown that this relationship exhibits exponential decay behavior, with sublimation rate significantly dampened under less than 10 cm of till. In our experiments we pay particular attention to the effect of the first several cm of till in order to quantify the dynamics that govern the transition from bare ice to debris-covered ice. We also examine this transition for various forms of glacier ice, including ice with various salt species.

  1. Analysis of a SNP linked to lactase persistence: An exercise for teaching molecular biology techniques to undergraduates.

    Science.gov (United States)

    Schultheis, Patrick J; Bowling, Bethany V

    2011-01-01

    Recent experimental evidence indicates that the ability of adults to tolerate milk, cheese, and other lactose-containing dairy products is an autosomal dominant trait that co-evolved with dairy farming in Central Europe about 7,500 years ago. Among persons of European descent, this trait is strongly associated with a C to T substitution at a polymorphic site 13,910 bp upstream of the lactase gene. This mutation results in the persistent expression of lactase into adulthood enabling individuals carrying a T(-13,910) allele to digest lactose as adults. In this report, we describe a laboratory exercise for an undergraduate molecular biology course in which students determine their own genotype at the -13,910 polymorphic site and correlate this with their ability to tolerate dairy products. The exercise is used as a tool to teach basic molecular biology procedures such as agarose gel electrophoresis, PCR1, and DNA sequencing. Students are actively engaged in the learning process, not only by analyzing their own DNA but also by applying their knowledge and skills to answer an authentic question. The exercise is also integrated with lecture material on the control of gene expression at the transcriptional level, in particular, how transcription factors can influence the activity of a promoter by binding to cis-acting DNA regulatory elements located within the proximal promoter of a gene or distant enhancer regions. Copyright © 2010 Wiley Periodicals, Inc.

  2. Detecting the dormant: a review of recent advances in molecular techniques for assessing the viability of bacterial endospores.

    Science.gov (United States)

    Mohapatra, Bidyut R; La Duc, Myron T

    2013-09-01

    Due to their contribution to gastrointestinal and pulmonary disease, their ability to produce various deadly exotoxins, and their resistance to extreme temperature, pressure, radiation, and common chemical disinfecting agents, bacterial endospores of the Firmicutes phylum are a major concern for public and environmental health. In addition, the hardy and dormant nature of endospores renders them a particularly significant threat to the integrity of robotic extraterrestrial life-detection investigations. To prevent the contamination of critical surfaces with seemingly ubiquitous bacterial endospores, clean rooms maintained at exceedingly stringent cleanliness levels (i.e., fewer than 100,000 airborne particles per ft(3)) are used for surgical procedures, pharmaceutical processing and packaging, and fabrication and assembly of medical devices and spacecraft components. However, numerous spore-forming bacterial species have been reported to withstand typical clean room bioreduction strategies (e.g., UV lights, maintained humidity, paucity of available nutrients), which highlights the need for rapid and reliable molecular methods for detecting, enumerating, and monitoring the incidence of viable endospores. Robust means of evaluating and tracking spore burden not only provide much needed information pertaining to endospore ecophysiology in different environmental niches but also empower decontamination and bioreduction strategies aimed at sustaining the reliability and integrity of clean room environments. An overview of recent molecular advances in detecting and enumerating viable endospores, as well as the expanding phylogenetic diversity of pathogenic and clean room-associated spore-forming bacteria, ensues.

  3. Extensive Evaluation of a Diffusion Denuder Technique for the Quantification of Atmospheric Stable and Radioactive Molecular Iodine

    DEFF Research Database (Denmark)

    Huang, Ru-Jin; Hou, Xiaolin; Hoffmann, Thorsten

    2010-01-01

    In this paper we present the evaluation and optimization of a new approach for the quantification of gaseous molecular iodine (I2) for laboratory- and field-based studies and its novel application for the measurement of radioactive molecular iodine. α-Cyclodextrin (α-CD) in combination with 129I......, and condition of release and derivatization of iodine, is extensively evaluated and optimized. The collection efficiency is larger than 98% and the limit of detection (LOD) obtained is 0.17 parts-per-trillion-by-volume (pptv) for a sampling duration of 30 min at 500 mL min−1. Furthermore, the potential use...... of this protocol for the determination of radioactive I2 at ultra trace level is also demonstrated when 129I− used in the coating is replaced by 127I− and a multiple denuder system is used. Using the present method we observed 25.7−108.6 pptv 127I2 at Mweenish Bay, Ireland and 108 molecule m−3 129I2 at Mainz...

  4. Comparison of molecular techniques with other methods for identification and enumeration of probiotics in fermented milk products.

    Science.gov (United States)

    Bagheripoor-Fallah, Niloofar; Mortazavian, Amir; Hosseini, Hedayat; Khoshgozaran-Abras, Sadegh; Rad, Aziz Homayouni

    2015-01-01

    Nowadays, an increasing attention is being given to fermented milk products including yogurt, kefir, buttermilk, and acidophilus milk. Fermented milks, especially the ones containing probiotics, are claimed to be useful for health of host (such as intestinal- and immune-associated diseases). Their healthful effects could be significantly enhanced by incorporating probiotic microorganisms; those have healthful advantages for host when consumed in an appropriate viable number in food products. Probiotic dairy products have stepped to the market and are being commercially produced under various brand names. In addition, these products are legislatively obliged to be labeled for the microorganisms contained. Therefore, identification and enumeration of their microorganisms are a cause of concern. Several culture-dependent methods have been introduced and used to identify the microorganisms, in which the researchers have experienced multiple difficulties. Thereby, molecular approaches were present as an alternative, offering advantages such as accuracy, sensitivity, specificity, and speed. This article reviews the molecular approaches employed for identification and enumeration of probiotics in fermented milk products.

  5. Interaction of Flavonoids from Woodwardia unigemmata with Bovine Serum Albumin (BSA): Application of Spectroscopic Techniques and Molecular Modeling Methods.

    Science.gov (United States)

    Ma, Rui; Pan, Hong; Shen, Tao; Li, Peng; Chen, Yanan; Li, Zhenyu; Di, Xiaxia; Wang, Shuqi

    2017-08-09

    Phytochemical investigation on the methanol extract of Woodwardia unigemmata resulted in the isolation of seven flavonoids, including one new flavonol acylglycoside ( 1 ). The structures of these compounds were elucidated on the basis of extensive spectroscopic analysis and comparison of literature data. The multidrug resistance (MDR) reversing activity was evaluated for the isolated compounds using doxorubicin-resistant K562/A02 cells model. Compound 6 showed comparable MDR reversing effect to verapamil. Furthermore, the interaction between compounds and bovine serum albumin (BSA) was investigated by spectroscopic methods, including steady-state fluorescence, synchronous fluorescence, circular dichroism (CD) spectroscopies, and molecular docking approach. The experimental results indicated that the seven flavonoids bind to BSA by static quenching mechanisms. The negative ΔH and ΔS values indicated that van der Waals interactions and hydrogen bonds contributed in the binding of compounds 2 - 6 to BSA. In the case of compounds 1 and 7 systems, the hydrophobic interactions play a major role. The binding of compounds to BSA causes slight changes in the secondary structure of BSA. There are two binding sites of compound 6 on BSA and site I is the main site according to the molecular docking studies and the site marker competitive binding assay.

  6. An overview of techniques for linking high-dimensional molecular data to time-to-event endpoints by risk prediction models.

    Science.gov (United States)

    Binder, Harald; Porzelius, Christine; Schumacher, Martin

    2011-03-01

    Analysis of molecular data promises identification of biomarkers for improving prognostic models, thus potentially enabling better patient management. For identifying such biomarkers, risk prediction models can be employed that link high-dimensional molecular covariate data to a clinical endpoint. In low-dimensional settings, a multitude of statistical techniques already exists for building such models, e.g. allowing for variable selection or for quantifying the added value of a new biomarker. We provide an overview of techniques for regularized estimation that transfer this toward high-dimensional settings, with a focus on models for time-to-event endpoints. Techniques for incorporating specific covariate structure are discussed, as well as techniques for dealing with more complex endpoints. Employing gene expression data from patients with diffuse large B-cell lymphoma, some typical modeling issues from low-dimensional settings are illustrated in a high-dimensional application. First, the performance of classical stepwise regression is compared to stage-wise regression, as implemented by a component-wise likelihood-based boosting approach. A second issues arises, when artificially transforming the response into a binary variable. The effects of the resulting loss of efficiency and potential bias in a high-dimensional setting are illustrated, and a link to competing risks models is provided. Finally, we discuss conditions for adequately quantifying the added value of high-dimensional gene expression measurements, both at the stage of model fitting and when performing evaluation. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Effects of irradiated pollen assisting pollination technique on seedset of lily's distant cross and early molecular identification of the hybrids

    International Nuclear Information System (INIS)

    Jia Yuehui; Zhang Kezhong; Li Wenxue; Zhang Fusuo

    2010-01-01

    The effects of the irradiated pollen assisting pollination technique on seedset of the lily' pollyanna' (female) x Lilium dauricum were investigated. A number of fruits and plump seeds were produced by using the normal stigma pollination, which indicated that the cross was a compatible cross. The application of 1000 and 2500Gy irradiated pollen assisting pollination increased the seedset obviously, which showed that this method could overcome the cross barriers effectively. More seedsets means that more excellent individuals might be selected from F 1 hybrids. 15 random F 1 individuals were selected for parentage identification by ISSR-PCR technique. Total 372 bands were generated from 6 primers' ISSR-PCR amplification, in which 114 bands were the male parent characteristic bands, 67 were the female parent characteristic bands, 65 were the parents common bands, and ISSR analysis showed that they were really hybrids. (authors)

  8. Changing techniques in crop plant classification: molecularization at the National Institute of Agricultural Botany during the 1980s.

    Science.gov (United States)

    Holmes, Matthew

    2017-04-01

    Modern methods of analysing biological materials, including protein and DNA sequencing, are increasingly the objects of historical study. Yet twentieth-century taxonomic techniques have been overlooked in one of their most important contexts: agricultural botany. This paper addresses this omission by harnessing unexamined archival material from the National Institute of Agricultural Botany (NIAB), a British plant science organization. During the 1980s the NIAB carried out three overlapping research programmes in crop identification and analysis: electrophoresis, near infrared spectroscopy (NIRS) and machine vision systems. For each of these three programmes, contemporary economic, statutory and scientific factors behind their uptake by the NIAB are discussed. This approach reveals significant links between taxonomic practice at the NIAB and historical questions around agricultural research, intellectual property and scientific values. Such links are of further importance given that the techniques developed by researchers at the NIAB during the 1980s remain part of crop classification guidelines issued by international bodies today.

  9. Fluorescence perturbation techniques to study mobility and molecular dynamics of proteins in live cells: FRAP, photoactivation, photoconversion, and FLIP.

    Science.gov (United States)

    Bancaud, Aurélien; Huet, Sébastien; Rabut, Gwénaël; Ellenberg, Jan

    2010-12-01

    The technique of fluorescence recovery after photobleaching (FRAP) was introduced in the mid-1970s to study the diffusion of biomolecules in living cells. For several years, it was used mainly by a small number of biophysicists who had developed their own photobleaching systems. Since the mid-1990s, FRAP has gained increasing popularity because of the conjunction of two factors: First, photobleaching techniques are easily implemented on confocal laser-scanning microscopes (CLSMs), and so FRAP has become available to anyone who has access to such equipment. Second, the advent of green fluorescent protein (GFP) has allowed easy fluorescent tagging of proteins and their observation in living cells. Thanks both to the versatility of modern CLSMs, which allow control of laser intensity at any point of the image, and to the development of new fluorescent probes, additional photoperturbation techniques have emerged during the last few years. After the photoperturbation event, one observes and then analyzes how the fluorescence distribution relaxes toward the steady state. Because the photochemical perturbation of suitable fluorophores is essentially irreversible, changes of fluorescence intensity in the perturbed and unperturbed regions are due to the exchange of tagged molecules between those regions. This article first discusses the materials required for performing FRAP experiments on a CLSM and the software for data analysis. It then describes general considerations on how to perform FRAP experiments as well as the necessary controls. Finally, different possible ways to analyze the data are presented.

  10. Characterisation of the yeast and mould biota in traditional white pickled cheeses by culture-dependent and independent molecular techniques.

    Science.gov (United States)

    Šuranská, Hana; Raspor, Peter; Uroić, Ksenija; Golić, Nataša; Kos, Blaženka; Mihajlović, Sanja; Begović, Jelena; Šušković, Jagoda; Topisirović, Ljubiša; Čadež, Neža

    2016-11-01

    Artisanal white pickled cheese of Western Serbia is a product of complex microbial community which detection by culture-dependent method only is hampered by its limitations. Thus, in the present study, we used a culture-independent, semi-quantitative technique based on construction of an internal transcribed spacer (ITS)-clone library from metagenomic DNA. This approach, based on direct DNA extraction followed by amplification of fungal internal transcribed regions (ITS) cloned into plasmid and restricted by endonucleases, revealed greater species richness in analysed cheeses and their by-products (17 species in total) compared to the more commonly used techniques of the culture-dependent method (8 species) and LSU-DGGE (10 species). The most frequently occurring yeast species which are commonly associated with cheeses production were Debaryomyces hansenii, Kluyveromyces lactis and Candida zeylanoides. On the other hand, Yarrowia lipolytica and Galactomyces geotrichum were detected only in one cheese sample. Moreover, some species, mainly moulds (Filobasidium globisporum, Cladosporium sp., Aspergillus sp. or Alternaria sp.) were identified only by culture-independent methods. The discrepancies between the techniques were confirmed by low correlation factor and by different indices of general biodiversity and dominance of species. The ITS-clone library approach provides the opportunity to analyse complex fungal communities associated with food products.

  11. Evaluation of parasitological and molecular techniques for the diagnosis and assessment of cure of schistosomiasis mansoni in a low transmission area.

    Science.gov (United States)

    Siqueira, Liliane Maria Vidal; Gomes, Luciana Inácia; Oliveira, Edward; Oliveira, Eduardo Ribeiro de; Oliveira, Áureo Almeida de; Enk, Martin Johannes; Carneiro, Nídia Figueiredo; Rabello, Ana; Coelho, Paulo Marcos Zech

    2015-04-01

    This study evaluated parasitological and molecular techniques for the diagnosis and assessment of cure of schistosomiasis mansoni. A population-based study was performed in 201 inhabitants from a low transmission locality named Pedra Preta, municipality of Montes Claros, state of Minas Gerais, Brazil. Four stool samples were analysed using two techniques, the Kato-Katz® (KK) technique (18 slides) and the TF-Test®, to establish the infection rate. The positivity rate of 18 KK slides of four stool samples was 28.9% (58/201) and the combined parasitological techniques (KK+TF-Test®) produced a 35.8% positivity rate (72/201). Furthermore, a polymerase chain reaction (PCR)-ELISA assay produced a positivity rate of 23.4% (47/201) using the first sample. All 72 patients with positive parasitological exams were treated with a single dose of Praziquantel® and these patients were followed-up 30, 90 and 180 days after treatment to establish the cure rate. Cure rates obtained by the analysis of 12 KK slides were 100%, 100% and 98.4% at 30, 90 and 180 days after treatment, respectively. PCR-ELISA revealed cure rates of 98.5%, 95.5% and 96.5%, respectively. The diagnostic and assessment of cure for schistosomiasis may require an increased number of KK slides or a test with higher sensitivity, such as PCR-ELISA, in situations of very low parasite load, such as after therapeutic interventions.

  12. Evidence for molecular antagonistic mechanism between mercury and selenium in rice (Oryza sativa L.): A combined study using 1, 2-dimensional electrophoresis and SR-XRF techniques.

    Science.gov (United States)

    Li, Yunyun; Li, Hong; Li, Yu-Feng; Zhao, Jiating; Guo, Jingxia; Wang, Ru; Li, Bai; Zhang, Zhiyong; Gao, Yuxi

    2017-10-16

    Mercury (Hg) is a hazardous chemical in the environment and can accumulate in the food chain. Selenium (Se) is a necessary element for human health and has antagonistic effects on Hg toxicity. In this work, we investigated the effect of Se on Hg containing and Hg-responsive proteins in rice using 1, 2-dimensional electrophoresis combined with SR-XRF techniques. Two weeks old rice seedlings were exposed to Hg and/or Se compounds. After 21days proteins in the rice roots were separated by electrophoresis and their metal contents were determined by X-ray fluorescence to identify Hg and Se responsive biomolecules. The results show that under Hg stress alone Hg is bound to proteins with molecular weights of 15-25kDa. With the addition of Se, a new Hg-containing protein band in the 55-70kDa range was also found, while the content of Hg in the 15-25kDa proteins decreased. Ten and nine new protein spots were identified after adding Se to inorganic Hg and methylmercury exposed roots, respectively. Adding Se regulates the abundance of proteins associated with carbohydrate and energy metabolism, stress response, cell cycle, and DNA replication indicating that these proteins mediate the antagonism of Se against Hg toxicity. This study helps us to better understand the molecular mechanism of Hg tolerance as well as the molecular antagonism between Hg and Se in rice plants. Copyright © 2017 Elsevier GmbH. All rights reserved.

  13. Shape and Size Characteristics of Bedload Transported During Winter Storm Events in the Cwm Treweryn Stream, Brecon Beacons, South Wales

    OpenAIRE

    WALSH, TUNCER DEMİR & RORY PETER DOMINIC

    2005-01-01

    Bedload transport in the Cwm Treweryn stream, a tributary of the Usk in the Brecon Beacons, South Wales, was investigated during a wet winter period in early 1995 using basket-type bedload traps and the tracing of painted clasts. The Cwm Treweryn is a typical mountain stream of the region with its gravel-bedload, flashy regime, high gradient and pool-riffle sequences. In particular, the study explored - for a range of categories of clast size - the nature of any influence of clast shape on be...

  14. Potential effects of the introduction of the discrete address beacon system data link on air/ground information transfer problems

    Science.gov (United States)

    Grayson, R. L.

    1981-01-01

    This study of Aviation Safety Reporting System reports suggests that benefits should accure from implementation of discrete address beacon system data link. The phase enhanced terminal information system service is expected to provide better terminal information than present systems by improving currency and accuracy. In the exchange of air traffic control messages, discrete address insures that only the intended recipient receives and acts on a specific message. Visual displays and printer copy of messages should mitigate many of the reported problems associated with voice communications. The problems that remain unaffected include error in addressing the intended recipient and messages whose content is wrong but are otherwise correct as to format and reasonableness.

  15. Microprobing the Molecular Spatial Distribution and Structural Architecture of Feed-type Sorghum Seed Tissue (Sorghum Bicolor L.) using the Synchrotron Radiation Infrared Microspectroscopy Technique

    Energy Technology Data Exchange (ETDEWEB)

    P Yu

    2011-12-31

    Sorghum seed (Sorghum bicolor L.) has unique degradation and fermentation behaviours compared with other cereal grains such as wheat, barley and corn. This may be related to its cell and cell-wall architecture. The advanced synchrotron radiation infrared microspectroscopy (SR-IMS) technique enables the study of cell or living cell biochemistry within cellular dimensions. The objective of this study was to use the SR-IMS imaging technique to microprobe molecular spatial distribution and cell architecture of the sorghum seed tissue comprehensively. High-density mapping was carried out using SR-IMS on beamline U2B at the National Synchrotron Light Source (Brookhaven National Laboratory, NY, USA). Molecular images were systematically recorded from the outside to the inside of the seed tissue under various chemical functional groups and their ratios [peaks at {approx}1725 (carbonyl C=O ester), 1650 (amide I), 1657 (protein secondary structure {alpha}-helix), 1628 (protein secondary structure {beta}-sheet), 1550 (amide II), 1515 (aromatic compounds of lignin), 1428, 1371, 1245 (cellulosic compounds in plant seed tissue), 1025 (non-structural CHO, starch granules), 1246 (cellulosic material), 1160 (CHO), 1150 (CHO), 1080 (CHO), 930 (CHO), 860 (CHO), 3350 (OH and NH stretching), 2960 (CH{sub 3} anti-symmetric), 2929 (CH{sub 2} anti-symmetric), 2877 (CH{sub 3} symmetric) and 2848 cm{sup -1} (CH{sub 2} asymmetric)]. The relative protein secondary structure {alpha}-helix to {beta}-sheet ratio image, protein amide I to starch granule ratio image, and anti-symmetric CH{sub 3} to CH{sub 2} ratio image were also investigated within the intact sorghum seed tissue. The results showed unique cell architecture, and the molecular spatial distribution and intensity in the sorghum seed tissue (which were analyzed through microprobe molecular imaging) were generated using SR-IMS. This imaging technique and methodology has high potential and could be used for scientists to develop

  16. Microprobing the molecular spatial distribution and structural architecture of feed-type sorghum seed tissue (Sorghum Bicolor L.) using the synchrotron radiation infrared microspectroscopy technique.

    Science.gov (United States)

    Yu, Peiqiang

    2011-09-01

    Sorghum seed (Sorghum bicolor L.) has unique degradation and fermentation behaviours compared with other cereal grains such as wheat, barley and corn. This may be related to its cell and cell-wall architecture. The advanced synchrotron radiation infrared microspectroscopy (SR-IMS) technique enables the study of cell or living cell biochemistry within cellular dimensions. The objective of this study was to use the SR-IMS imaging technique to microprobe molecular spatial distribution and cell architecture of the sorghum seed tissue comprehensively. High-density mapping was carried out using SR-IMS on beamline U2B at the National Synchrotron Light Source (Brookhaven National Laboratory, NY, USA). Molecular images were systematically recorded from the outside to the inside of the seed tissue under various chemical functional groups and their ratios [peaks at ∼1725 (carbonyl C=O ester), 1650 (amide I), 1657 (protein secondary structure α-helix), 1628 (protein secondary structure β-sheet), 1550 (amide II), 1515 (aromatic compounds of lignin), 1428, 1371, 1245 (cellulosic compounds in plant seed tissue), 1025 (non-structural CHO, starch granules), 1246 (cellulosic material), 1160 (CHO), 1150 (CHO), 1080 (CHO), 930 (CHO), 860 (CHO), 3350 (OH and NH stretching), 2960 (CH(3) anti-symmetric), 2929 (CH(2) anti-symmetric), 2877 (CH(3) symmetric) and 2848 cm(-1) (CH(2) asymmetric)]. The relative protein secondary structure α-helix to β-sheet ratio image, protein amide I to starch granule ratio image, and anti-symmetric CH(3) to CH(2) ratio image were also investigated within the intact sorghum seed tissue. The results showed unique cell architecture, and the molecular spatial distribution and intensity in the sorghum seed tissue (which were analyzed through microprobe molecular imaging) were generated using SR-IMS. This imaging technique and methodology has high potential and could be used for scientists to develop specific cereal grain varieties with targeted food and

  17. Preparation and evaluation of Exendin radio conjugates for detecting insulinomas and gastrinomas by molecular nuclear medicine techniques

    International Nuclear Information System (INIS)

    Medina G, V.

    2015-01-01

    The gastro-entero-pancreatic neuroendocrine tumors (GEP-NET) are named based on the secreted hormones. Among them, the insulinomas and gastrinomas represent a diagnostic challenge because of their slow metabolic rate, small size and anatomical location that have limited their detection in some imaging procedures. About 90% of insulinomas are benign and 10% are malignant. Benign insulinomas express the glucagon-like peptide-1 receptor (GLP-1R) and low levels of somatostatin receptors (SSTR), while malignant insulinomas over express SSTR or GLP-1R in low levels. A kit for the preparation of Lys 27 ( 99m Tc-EDDA/HYNIC)-Exendin(9-39)/ 99m Tc-EDDA/HYNIC-Tyr 3 -Octreotide was developed to detect 100% of gastrinomas and insulinomas. In order to reach this aim, the peptides were radiolabeled and characterized. Stability studies will be completed and the in vitro and in vivo behavior was evaluated. The Lys 27 ( 99m Tc-EDDA/HYNIC)-Exendin(9-39)/ 99m Tc-EDDA/HYNIC-Tyr 3 -Octreotide can be labeled with 99m Tc, obtaining high radiochemical purities (>94%), high stability in human serum and affinity to GLP-1 and SST-2 receptor. This new formulation showed properties suitable for use as a target-specific agent for molecular imaging of GLP-1R/SSTR positive tumors. In vivo micro-SPECT/CT images of Lys 27 ( 99m Tc-EDDA/HYNIC)-Exendin(9-39), 99m Tc-EDDA/HYNIC-Tyr 3 -Octreotide and of the pharmaceutical formulation Lys 27 ( 99m Tc-EDDA/HYNIC)-Exendin(9-39)/ 99m Tc-EDDA/HYNIC-Tyr 3 -Octreotide showed the main elimination pathways, and tumors higher uptake compared to the background tissues. The biodistribution and imaging studies demonstrated properties suitable for its use as a target-specific agent for the simultaneous molecular imaging of GLP-1R and SSTR. (Author)

  18. Simultaneous measurements of droplet size, flying velocity and transient temperature of in-flight droplets by using a molecular tagging technique

    Science.gov (United States)

    Li, Haixing; Chen, Fang; Hu, Hui

    2015-10-01

    In the present study, a molecular tagging technique is introduced to achieve simultaneous measurements of droplet size, flying velocity and transient temperature of in-flight liquid droplets in a spray flow. For the molecular tagging measurements, a pulsed laser is used to "tag" phosphorescent 1-BrNp·Mβ-CD·ROH triplex molecules premixed within liquid droplets. After the same laser excitation pulse, long-lived laser-induced phosphorescence is imaged at two successive times within the phosphorescence lifetime of the tagged phosphorescent triplex molecules. While the sizes of the droplets are determined quantitatively based on the acquired droplet images with a precalibrated scale ratio between the image plane and the object plane, the displacement vectors of the in-flight droplets between the two image acquisitions are used to estimate the flying velocities of the droplets. The simultaneous measurements of the transient temperatures of the in-flight droplets are achieved by taking advantage of the temperature dependence of phosphorescence lifetime, which is estimated from the intensity ratio of the acquired phosphorescence image pair of the inflight droplets. The feasibility and implementation of the molecular tagging technique are demonstrated by conducting simultaneous measurements of droplet size, flying velocity and transient temperature of micro-sized water droplets exhausted from a piezoelectric droplet generator into ambient air at different test conditions in order to characterize the dynamic and thermodynamic behaviors of the micro-sized in-flight droplets. The unsteady heat transfer process between the in-flight droplets and the ambient air is also analyzed theoretically by using a lumped capacitance method to predict the temperature changes of the in-flight water droplets along their flight trajectories. The measured temperature data are compared with the theoretical analysis results quantitatively, and the discrepancies between measurement results and

  19. Biomimetic polymers in analytical chemistry. Part 1: preparation and applications of MIP (Molecularly Imprinted Polymers) in extraction and separation techniques

    International Nuclear Information System (INIS)

    Tarley, Cesar Ricardo Teixeira; Sotomayor, Maria del Pilar Taboada; Kubota, Lauro Tatsuo

    2005-01-01

    MIPs are synthetic polymers that are used as biomimetic materials simulating the mechanism verified in natural entities such as antibodies and enzymes. Although MIPs have been successfully used as an outstanding tool for enhancing the selectivity or different analytical approaches, such as separation science and electrochemical and optical sensors, several parameters must be optimized during their synthesis. Therefore, the state-of-the-art of MIP production as well as the different polymerization methods are discussed. The potential selectivity of MIPs in the extraction and separation techniques focusing mainly on environmental, clinical and pharmaceutical samples as applications for analytical purposes is presented. (author)

  20. Formation and properties of epitaxial CdSe, ZnSe quantum dots. Conventional molecular beam epitaxy and related techniques

    Energy Technology Data Exchange (ETDEWEB)

    Mahapatra, Suddhasatta

    2008-01-16

    This thesis systematically investigates three such alternative approaches, along with conventional MBE, with emphasis on the formation-mechanism of QDs, and optimization of their morphological and optical attributes. it is shown here that no distinct 3D islands are formed in MBE growth of CdSe on ZnSe. While CdSe heteroepitaxy occurs in the multilayer-mode at T{sub G}=300 C, a reentrant recovery of the layer-by-layer mode is reported in this thesis, for growth at T{sub G}<{proportional_to}240 C. In the second variant technique, formation of large and distinct islands is demonstrated by deposition of amorphous selenium (a-Se) onto a 2D CdSe epilayer at room temperature and its subsequent desorption at a higher temperature (T{sub D}=230 C). The process steps of the third variant technique, developed in course of this work, are very similar to those of the previous one-the only alteration being the substitution of selenium with tellurium as the cap-forming-material. (orig.)

  1. Molecular Techniques Revealed Highly Diverse Microbial Communities in Natural Marine Biofilms on Polystyrene Dishes for Invertebrate Larval Settlement

    KAUST Repository

    Lee, On On

    2014-01-09

    Biofilm microbial communities play an important role in the larval settlement response of marine invertebrates. However, the underlying mechanism has yet to be resolved, mainly because of the uncertainties in characterizing members in the communities using traditional 16S rRNA gene-based molecular methods and in identifying the chemical signals involved. In this study, pyrosequencing was used to characterize the bacterial communities in intertidal and subtidal marine biofilms developed during two seasons. We revealed highly diverse biofilm bacterial communities that varied with season and tidal level. Over 3,000 operational taxonomic units with estimates of up to 8,000 species were recovered in a biofilm sample, which is by far the highest number recorded in subtropical marine biofilms. Nineteen phyla were found, of which Cyanobacteria and Proteobacteria were the most dominant one in the intertidal and subtidal biofilms, respectively. Apart from these, Actinobacteria, Bacteroidetes, and Planctomycetes were the major groups recovered in both intertidal and subtidal biofilms, although their relative abundance varied among samples. Full-length 16S rRNA gene clone libraries were constructed for the four biofilm samples and showed similar bacterial compositions at the phylum level to those revealed by pyrosequencing. Laboratory assays confirmed that cyrids of the barnacle Balanus amphitrite preferred to settle on the intertidal rather than subtidal biofilms. This preference was independent of the biofilm bacterial density or biomass but was probably related to the biofilm community structure, particularly, the Proteobacterial and Cyanobacterial groups. © 2014 Springer Science+Business Media New York.

  2. GaAsBi/GaAs multi-quantum well LED grown by molecular beam epitaxy using a two-substrate-temperature technique

    Science.gov (United States)

    Kisan Patil, Pallavi; Luna, Esperanza; Matsuda, Teruyoshi; Yamada, Kohki; Kamiya, Keisuke; Ishikawa, Fumitaro; Shimomura, Satoshi

    2017-03-01

    We report a GaAs0.96Bi0.04/GaAs multiple quantum well (MQW) light emitting diode (LED) grown by molecular beam epitaxy using a two-substrate-temperature (TST) technique. In particular, the QWs and the barriers in the intrinsic region were grown at the different temperatures of {T}{{GaAsBi}} = 350 °C and {T}{{GaAs}} = 550 ^\\circ {{C}}, respectively. Investigations of the microstructure using transmission electron microscopy (TEM) reveal homogeneous MQWs free of extended defects. Furthermore, the local determination of the Bi distribution profile across the MQWs region using TEM techniques confirm the uniform Bi distribution, while revealing a slightly chemically graded GaAs-on-GaAsBi interface due to Bi surface segregation. Despite this small broadening, we found that Bi segregation is significantly reduced (up to 18% reduction) compared to previous reports on Bi segregation in GaAsBi/GaAs MQWs. Hence, the TST procedure proves as a very efficient method to reduce Bi segregation and thus increase the quality of the layers and interfaces. These improvements positively reflect in the optical properties. Room temperature photoluminescence and electroluminescence (EL) at 1.23 μm emission wavelength are successfully demonstrated using TST MQWs containing less Bi content than in previous reports. Finally, LED fabricated using the present TST technique show current-voltage (I-V) curves with a forward voltage of 3.3 V at an injection current of 130 mA under 1.0 kA cm-2 current excitation. These results not only demonstrate that TST technique provides optical device quality GaAsBi/GaAs MQWs but highlight the relevance of TST-based growth techniques on the fabrication of future heterostructure devices based on dilute bismides.

  3. Formation and properties of epitaxial CdSe, ZnSe quantum dots. Conventional molecular beam epitaxy and related techniques

    International Nuclear Information System (INIS)

    Mahapatra, Suddhasatta

    2008-01-01

    This thesis systematically investigates three such alternative approaches, along with conventional MBE, with emphasis on the formation-mechanism of QDs, and optimization of their morphological and optical attributes. it is shown here that no distinct 3D islands are formed in MBE growth of CdSe on ZnSe. While CdSe heteroepitaxy occurs in the multilayer-mode at T G =300 C, a reentrant recovery of the layer-by-layer mode is reported in this thesis, for growth at T G D =230 C). The process steps of the third variant technique, developed in course of this work, are very similar to those of the previous one-the only alteration being the substitution of selenium with tellurium as the cap-forming-material. (orig.)

  4. A novel strategy for human papillomavirus detection and genotyping with SybrGreen and molecular beacon polymerase chain reaction

    NARCIS (Netherlands)

    Szuhai, K; Sandhaus, E; Kolkman-Uljee, SM; Lemaitre, M; Truffert, JC; Dirks, RW; Tanke, HJ; Fleuren, GJ; Schuuring, E; Raap, AK

    2001-01-01

    Human papillomaviruses (HPVs) play an important role in the pathogenesis of cervical cancer. For identification of the large number of different HPV types found in (pre)malignant lesions, a robust methodology is needed that combines general HPV detection with HPV genotyping. We have developed for

  5. A catalytic and dual recycling amplification ATP sensor based on target-driven allosteric structure switching of aptamer beacons.

    Science.gov (United States)

    Peng, Ying; Li, Daxiu; Yuan, Ruo; Xiang, Yun

    2018-05-15

    Abnormal concentrations of ATP are associated with many diseases and cancers, and quantitative detection of ATP is thus of great importance for disease diagnosis and prognosis. In the present work, we report a new dual recycling amplification sensor integrated with catalytic hairpin assembly (CHA) to achieve high sensitivity for fluorescent detection of ATP. The association of the target ATP with the aptamer beacons causes the allosteric structure switching of the aptamer beacons to expose the toehold regions, which hybridize with and unfold the fluorescently quenched hairpin signal probes (HP1) to recycle the target ATP and to trigger CHA between HP1 and the secondary hairpin probes (HP2) to form HP1/HP2 duplexes. Due to the recycling amplification, the presence of ATP leads to the formation of many HP1/HP2 duplexes, generating dramatically amplified fluorescent signals for sensitive detection of ATP. Under optimal experimental conditions, our sensor linearly responds to ATP in the range from 25 to 600nM with a calculated detection limit of 8.2nM. Furthermore, the sensor shows a high selectivity and can also be used to detect ATP in human serums to realize its application for real samples. With the distinct advantage of significant signal amplification without the involvement of any nanomaterial and enzyme, the developed sensor thus holds great potential for simple and sensitive detection of different small molecules and proteins. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Design and Analysis of A Beacon-Less Routing Protocol for Large Volume Content Dissemination in Vehicular Ad Hoc Networks.

    Science.gov (United States)

    Hu, Miao; Zhong, Zhangdui; Ni, Minming; Baiocchi, Andrea

    2016-11-01

    Large volume content dissemination is pursued by the growing number of high quality applications for Vehicular Ad hoc NETworks(VANETs), e.g., the live road surveillance service and the video-based overtaking assistant service. For the highly dynamical vehicular network topology, beacon-less routing protocols have been proven to be efficient in achieving a balance between the system performance and the control overhead. However, to the authors' best knowledge, the routing design for large volume content has not been well considered in the previous work, which will introduce new challenges, e.g., the enhanced connectivity requirement for a radio link. In this paper, a link Lifetime-aware Beacon-less Routing Protocol (LBRP) is designed for large volume content delivery in VANETs. Each vehicle makes the forwarding decision based on the message header information and its current state, including the speed and position information. A semi-Markov process analytical model is proposed to evaluate the expected delay in constructing one routing path for LBRP. Simulations show that the proposed LBRP scheme outperforms the traditional dissemination protocols in providing a low end-to-end delay. The analytical model is shown to exhibit a good match on the delay estimation with Monte Carlo simulations, as well.

  7. Molecular beams

    International Nuclear Information System (INIS)

    Ramsey, N.F.

    1985-01-01

    This book is a timeless and rather complete theoretical and experimental treatment of electric and magnetic resonance molecular-beam experiments for studying the radio frequency spectra of atoms and molecules. The theory of interactions of the nucleus with atomic and molecular fields is extensively presented. Measurements of atomic and nuclear magnetic moments, electric multipole moments, and atomic fine and hyperfine structure are detailed. Useful but somewhat outdated chapters on gas kinetics, molecular beam design, and experimental techniques are also included

  8. Diagnosis of Familial Wolf-Hirschhorn Syndrome due to a Paternal Cryptic Chromosomal Rearrangement by Conventional and Molecular Cytogenetic Techniques

    Directory of Open Access Journals (Sweden)

    Carlos A. Venegas-Vega

    2013-01-01

    Full Text Available The use of conventional cytogenetic techniques in combination with fluorescent in situ hybridization (FISH and single-nucleotide polymorphism (SNP microarrays is necessary for the identification of cryptic rearrangements in the diagnosis of chromosomal syndromes. We report two siblings, a boy of 9 years and 9 months of age and his 7-years- and 5-month-old sister, with the classic Wolf-Hirschhorn syndrome (WHS phenotype. Using high-resolution GTG- and NOR-banding karyotypes, as well as FISH analysis, we characterized a pure 4p deletion in both sibs and a balanced rearrangement in their father, consisting in an insertion of 4p material within a nucleolar organizing region of chromosome 15. Copy number variant (CNV analysis using SNP arrays showed that both siblings have a similar size of 4p deletion (~6.5 Mb. Our results strongly support the need for conventional cytogenetic and FISH analysis, as well as high-density microarray mapping for the optimal characterization of the genetic imbalance in patients with WHS; parents must always be studied for recognizing cryptic balanced chromosomal rearrangements for an adequate genetic counseling.

  9. Nanosecond pulsed electric field incorporation technique to predict molecular mechanisms of teratogenicity and developmental toxicity of estradiol-17β on medaka embryos.

    Science.gov (United States)

    Yamaguchi, Akemi; Ishibashi, Hiroshi; Kono, Susumu; Iida, Midori; Uchida, Masaya; Arizono, Koji; Tominaga, Nobuaki

    2018-05-01

    Herein, we propose using a nanosecond pulsed electric field (nsPEF) technique to assess teratogenicity and embryonic developmental toxicity of estradiol-17β (E 2 ) and predict the molecular mechanisms of teratogenicity and embryonic developmental defects caused by E 2 on medaka (Oryzias latipes). The 5 hour post-fertilization embryos were exposed to co-treatment with 10 μm E 2 and nsPEF for 2 hours and then continuously cultured under non-E 2 and nsPEF conditions until hatching. Results documented that the time to hatching of embryos was significantly delayed in comparison to the control group and that typical abnormal embryo development, such as the delay of blood vessel formation, was observed. For DNA microarray analysis, 6 day post-fertilization embryos that had been continuously cultured under the non-E 2 and nsPEF condition after 2 hour co-treatments were used. DNA microarray analysis identified 542 upregulated genes and one downregulated gene in the 6 day post-fertilization embryos. Furthermore, bioinformatic analyses using differentially expressed genes revealed that E 2 exposure affected various gene ontology terms, such as response to hormone stimulus. The network analysis also documented that the estrogen receptor α in the mitogen-activated protein kinase signaling pathway may be involved in regulating several transcription factors, such as FOX, AKT1 and epidermal growth factor receptor. These results suggest that our nsPEF technique is a powerful tool for assessing teratogenicity and embryonic developmental toxicity of E 2 and predict their molecular mechanisms in medaka embryos. Copyright © 2017 John Wiley & Sons, Ltd.

  10. A semester-long project for teaching basic techniques in molecular biology such as restriction fragment length polymorphism analysis to undergraduate and graduate students.

    Science.gov (United States)

    DiBartolomeis, Susan M

    2011-01-01

    Several reports on science education suggest that students at all levels learn better if they are immersed in a project that is long term, yielding results that require analysis and interpretation. I describe a 12-wk laboratory project suitable for upper-level undergraduates and first-year graduate students, in which the students molecularly locate and map a gene from Drosophila melanogaster called dusky and one of dusky's mutant alleles. The mapping strategy uses restriction fragment length polymorphism analysis; hence, students perform most of the basic techniques of molecular biology (DNA isolation, restriction enzyme digestion and mapping, plasmid vector subcloning, agarose and polyacrylamide gel electrophoresis, DNA labeling, and Southern hybridization) toward the single goal of characterizing dusky and the mutant allele dusky(73). Students work as individuals, pairs, or in groups of up to four students. Some exercises require multitasking and collaboration between groups. Finally, results from everyone in the class are required for the final analysis. Results of pre- and postquizzes and surveys indicate that student knowledge of appropriate topics and skills increased significantly, students felt more confident in the laboratory, and students found the laboratory project interesting and challenging. Former students report that the lab was useful in their careers.

  11. Investigation into the interaction of losartan with human serum albumin and glycated human serum albumin by spectroscopic and molecular dynamics simulation techniques: A comparison study.

    Science.gov (United States)

    Moeinpour, Farid; Mohseni-Shahri, Fatemeh S; Malaekeh-Nikouei, Bizhan; Nassirli, Hooriyeh

    2016-09-25

    The interaction between losartan and human serum albumin (HSA), as well as its glycated form (gHSA) was studied by multiple spectroscopic techniques and molecular dynamics simulation under physiological conditions. The binding information, including the binding constants, effective quenching constant and number of binding sites showed that the binding partiality of losartan to HSA was higher than to gHSA. The findings of three-dimensional fluorescence spectra demonstrated that the binding of losartan to HSA and gHSA would alter the protein conformation. The distances between Trp residue and the binding sites of the drug were evaluated on the basis of the Förster theory, and it was indicated that non-radiative energy transfer from HSA and gHSA to the losartan happened with a high possibility. According to molecular dynamics simulation, the protein secondary and tertiary structure changes were compared in HSA and gHSA for clarifying the obtained results. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. A Semester-Long Project for Teaching Basic Techniques in Molecular Biology Such as Restriction Fragment Length Polymorphism Analysis to Undergraduate and Graduate Students

    Science.gov (United States)

    DiBartolomeis, Susan M.

    2011-01-01

    Several reports on science education suggest that students at all levels learn better if they are immersed in a project that is long term, yielding results that require analysis and interpretation. I describe a 12-wk laboratory project suitable for upper-level undergraduates and first-year graduate students, in which the students molecularly locate and map a gene from Drosophila melanogaster called dusky and one of dusky's mutant alleles. The mapping strategy uses restriction fragment length polymorphism analysis; hence, students perform most of the basic techniques of molecular biology (DNA isolation, restriction enzyme digestion and mapping, plasmid vector subcloning, agarose and polyacrylamide gel electrophoresis, DNA labeling, and Southern hybridization) toward the single goal of characterizing dusky and the mutant allele dusky73. Students work as individuals, pairs, or in groups of up to four students. Some exercises require multitasking and collaboration between groups. Finally, results from everyone in the class are required for the final analysis. Results of pre- and postquizzes and surveys indicate that student knowledge of appropriate topics and skills increased significantly, students felt more confident in the laboratory, and students found the laboratory project interesting and challenging. Former students report that the lab was useful in their careers. PMID:21364104

  13. BEACON/MOD2A: a computer program for subcompartment analysis of nuclear reactor containment. A user's manual. [PWR

    Energy Technology Data Exchange (ETDEWEB)

    Wells, R. A.

    1979-03-01

    The BEACON code is a Best Estimate Advanced Containment code which being developed by EG and G, Idaho, Inc., at the Idaho National Engineering Laboratory. The program is designed to perform a best estimate analysis of the flow of a mixture of air, water, and steam in a nuclear reactor containment system under loss-of-coolant accident conditions. The code can simulate two-component, two-phase fluid flow in complex geometries using a combination of two-dimensional, one-dimensional, and lumped-parameter representations for the various parts of the system. The current version of BEACON, which is designated BEACON/MOD2A, contains mass and heat transfer models for wall film and for wall conduction. It is suitable for the evaluation of short term transients in PWR dry containment systems. This manual describes the models employed in BEACON/MOD2A and specifies code implementation requirements. It provides application information for input data preparation and for output data interpretation.

  14. Investigation on the Interaction between Cyclophosphamide and Lysozyme in the Presence of Three Different Kind of Cyclodextrins: Determination of the Binding Mechanism by Spectroscopic and Molecular Modeling Techniques

    Directory of Open Access Journals (Sweden)

    Jamshidkhan Chamani

    2013-01-01

    Full Text Available The interactions between cyclophosphamide (CYC and lysozyme (LYZ in the presence of different cyclodextrins (CDs were investigated by UV absorption, fluorescence spectroscopy, circular dichroism (CD, and molecular modeling techniques under imitated physiological conditions. The UV absorption results showed the formation of complexes between CYC and LYZ in the presence of different CDs. Fluorescence data show that CYC has a stronger quenching effect on LYZ, and the red shifts suggested that the microenvironment of Trp residues was changed and became more hydrophilic. The interaction of CYC with LYZ and quenching properties of the complexes caused strong static fluorescence quenching in binary and ternary systems. The binding affinities as well as the number of binding sites were obtained from interaction between CYC and LYZ in the presence of different CDs as binary and ternary systems by modified Stern-Volmer plots. The Resonance Light Scattering (RLS technique was utilized to investigate the effect of drug and CDs on conformational changes of LYZ as separate and simultaneous. The results suggested that the enhancement of RLS intensity was attributed to the formation of a complex between drug and protein in absence and presence of CDs. The effect of CYC and cyclodextrins on the conformation of LYZ was analyzed using synchronous fluorescence spectroscopy. Our results revealed that the fluorescence quenching of LYZ originated from the Trp and Tyr residues, and demonstrated conformational changes of LYZ with the addition of CYC and CDs. The molecular distances between the donor (LYZ and acceptor (CYC and CDs in binary and ternary systems were estimated according to Forster’s theory and showed static quenching for protein with CYC in the presence of CDs. The CD spectra indicated that the binding of the CYC induced secondary structural changes in LYZ in binary and ternary systems. Molecular modeling suggested the binding sites of CYC in the ternary

  15. Species detection using HyBeacon(®) probe technology: Working towards rapid onsite testing in non-human forensic and food authentication applications.

    Science.gov (United States)

    Dawnay, Nick; Hughes, Rebecca; Court, Denise Syndercombe; Duxbury, Nicola

    2016-01-01

    Identifying individual species or determining species' composition in an unknown sample is important for a variety of forensic applications. Food authentication, monitoring illegal trade in endangered species, forensic entomology, sexual assault case work and counter terrorism are just some of the fields that can require the detection of the biological species present. Traditional laboratory based approaches employ a wide variety of tools and technologies and exploit a number of different species specific traits including morphology, molecular differences and immuno-chemical analyses. A large number of these approaches require laboratory based apparatus and results can take a number of days to be returned to investigating authorities. Having a presumptive test for rapid identification could lead to savings in terms of cost and time and allow sample prioritisation if confirmatory testing in a laboratory is required later. This model study describes the development of an assay using a single HyBeacon(®) probe and melt curve analyses allowing rapid screening and authentication of food products labelled as Atlantic cod (Gadus morhua). Exploiting melt curve detection of species specific SNP sites on the COI gene the test allows detection of a target species (Atlantic cod) and closely related species which may be used as substitutes. The assay has been designed for use with the Field Portable ParaDNA system, a molecular detection platform for non-expert users. The entire process from sampling to result takes approximately 75min. Validation studies were performed on both single source genomic DNA, mixed genomic DNA and commercial samples. Data suggests the assay has a lower limit of detection of 31 pg DNA. The specificity of the assay to Atlantic cod was measured by testing highly processed food samples including frozen, defrosted and cooked fish fillets as well as fish fingers, battered fish fillet and fish pie. Ninety-six (92.7%) of all Atlantic cod food products

  16. Application of molecular cytogenetic techniques to clarify apparently balanced complex chromosomal rearrangements in two patients with an abnormal phenotype: case report

    Directory of Open Access Journals (Sweden)

    Rongen Michel A

    2009-07-01

    Full Text Available Abstract Background Complex chromosomal rearrangements (CCR are rare cytogenetic findings that are difficult to karyotype by conventional cytogenetic analysis partially because of the relative low resolution of this technique. High resolution genotyping is necessary in order to identify cryptic imbalances, for instance near the multiple breakpoints, to explain the abnormal phenotype in these patients. We applied several molecular techniques to elucidate the complexity of the CCRs of two adult patients with abnormal phenotypes. Results Multicolour fluorescence in situ hybridization (M-FISH showed that in patient 1 the chromosomes 1, 10, 15 and 18 were involved in the rearrangement whereas for patient 2 the chromosomes 5, 9, 11 and 13 were involved. A 250 k Nsp1 SNP-array analysis uncovered a deletion in chromosome region 10p13 for patient 1, harbouring 17 genes, while patient 2 showed no pathogenic gains or losses. Additional FISH analysis with locus specific BAC-probes was performed, leading to the identification of cryptic interstitial structural rearrangements in both patients. Conclusion Application of M-FISH and SNP-array analysis to apparently balanced CCRs is useful to delineate the complex chromosomal rearrangement in detail. However, it does not always identify cryptic imbalances as an explanation for the abnormal phenotype in patients with a CCR.

  17. Evaluating the potential of thermal read-out techniques combined with molecularly imprinted polymers for the sensing of low-weight organic molecules.

    Science.gov (United States)

    van Grinsven, B; Betlem, K; Cleij, T J; Banks, C E; Peeters, M

    2017-01-01

    In recent years, there has been a tremendous increase in the papers published on synthetic recognition elements. Molecularly imprinted polymers (MIPs), also referred to as "man-made mimics" of antibodies, are able to rebind their template molecules with high affinity. Advantages compared with those of natural receptors include their excellent thermal and chemical stability, low cost, and ease of the production process. However, their use in commercial biosensors is limited owing to the difficulty to incorporate MIPs into suitable sensing platforms and traditional detection techniques, such as chromatography, that require bulky and sophisticated equipment. In this review, we evaluate the potential to use MIPs combined with thermal read-out for the detection of low-weight organic molecules. We discuss thermal methods to study MIP-template complexation and to determine neurotransmitters concentrations. In particular, we highlight the heat-transfer method, a recent technique that is straightforward and low cost and requires minimal instrumentation. Until now, sample preparation involves a 2-step process, making it time-consuming, and measuring biological samples is difficult owing to the noise in the signal. Different sample preparation methods are discussed, and it will be demonstrated how this affects the thermal response. An outlook is given in novel methods that can simplify and speed up sample preparation. Finally, we show a novel thermal technique, which is based on the analysis of transport of thermal waves rather than evaluating the fixed heat-transfer resistance. Through applying the concept of thermal waves, signal-noise ratio is significantly increased, which results in lower detection limits and has potential for the study of biological samples. Copyright © 2016 John Wiley & Sons, Ltd.

  18. Introducing Thermal Wave Transport Analysis (TWTA): A Thermal Technique for Dopamine Detection by Screen-Printed Electrodes Functionalized with Molecularly Imprinted Polymer (MIP) Particles.

    Science.gov (United States)

    Peeters, Marloes M; van Grinsven, Bart; Foster, Christopher W; Cleij, Thomas J; Banks, Craig E

    2016-04-26

    A novel procedure is developed for producing bulk modified Molecularly Imprinted Polymer (MIP) screen-printed electrodes (SPEs), which involves the direct mixing of the polymer particles within the screen-printed ink. This allowed reduction of the sample preparation time from 45 min to 1 min, and resulted in higher reproducibility of the electrodes. The samples are measured with a novel detection method, namely, thermal wave transport analysis (TWTA), relying on the analysis of thermal waves through a functional interface. As a first proof-of-principle, MIPs for dopamine are developed and successfully incorporated within a bulk modified MIP SPE. The detection limits of dopamine within buffer solutions for the MIP SPEs are determined via three independent techniques. With cyclic voltammetry this was determined to be 4.7 × 10(-6) M, whereas by using the heat-transfer method (HTM) 0.35 × 10(-6) M was obtained, and with the novel TWTA concept 0.26 × 10(-6) M is possible. This TWTA technique is measured simultaneously with HTM and has the benefits of reducing measurement time to less than 5 min and increasing effect size by nearly a factor of two. The two thermal methods are able to enhance dopamine detection by one order of magnitude compared to the electrochemical method. In previous research, it was not possible to measure neurotransmitters in complex samples with HTM, but with the improved signal-to-noise of TWTA for the first time, spiked dopamine concentrations were determined in a relevant food sample. In summary, novel concepts are presented for both the sensor functionalization side by employing screen-printing technology, and on the sensing side, the novel TWTA thermal technique is reported. The developed bio-sensing platform is cost-effective and suitable for mass-production due to the nature of screen-printing technology, which makes it very interesting for neurotransmitter detection in clinical diagnostic applications.

  19. Gastroesophageal reflux in relation to adenocarcinomas of the esophagus: a pooled analysis from the Barrett's and Esophageal Adenocarcinoma Consortium (BEACON.

    Directory of Open Access Journals (Sweden)

    Michael B Cook

    Full Text Available Previous studies have evidenced an association between gastroesophageal reflux and esophageal adenocarcinoma (EA. It is unknown to what extent these associations vary by population, age, sex, body mass index, and cigarette smoking, or whether duration and frequency of symptoms interact in predicting risk. The Barrett's and Esophageal Adenocarcinoma Consortium (BEACON allowed an in-depth assessment of these issues.Detailed information on heartburn and regurgitation symptoms and covariates were available from five BEACON case-control studies of EA and esophagogastric junction adenocarcinoma (EGJA. We conducted single-study multivariable logistic regressions followed by random-effects meta-analysis. Stratified analyses, meta-regressions, and sensitivity analyses were also conducted.Five studies provided 1,128 EA cases, 1,229 EGJA cases, and 4,057 controls for analysis. All summary estimates indicated positive, significant associations between heartburn/regurgitation symptoms and EA. Increasing heartburn duration was associated with increasing EA risk; odds ratios were 2.80, 3.85, and 6.24 for symptom durations of <10 years, 10 to <20 years, and ≥20 years. Associations with EGJA were slighter weaker, but still statistically significant for those with the highest exposure. Both frequency and duration of heartburn/regurgitation symptoms were independently associated with higher risk. We observed similar strengths of associations when stratified by age, sex, cigarette smoking, and body mass index.This analysis indicates that the association between heartburn/regurgitation symptoms and EA is strong, increases with increased duration and/or frequency, and is consistent across major risk factors. Weaker associations for EGJA suggest that this cancer site has a dissimilar pathogenesis or represents a mixed population of patients.

  20. How a Beacon Community Program in New Orleans Helped Create a Better Health Care System by Building Relationships before Technology.

    Science.gov (United States)

    Khurshid, Anjum; Brown, Lisanne

    2014-01-01

    In the aftermath of Hurricane Katrina, much of New Orleans' healthcare infrastructure was destroyed. Initial federal funding after the storm expanded primary care services and helped set up medical homes for New Orleans' large uninsured and underinsured population. Following that, the Beacon Community in New Orleans, charged with improving health care through the use of technology, decided the best way to accomplish those goals was to build community partnerships and introduce technology improvements based on their input and on their terms. The purpose of this paper is to describe how those partnerships were wrought, including the innovative use of a conceptual framework, and how they are being sustained; how different technologies were and are being introduced; and what the results have been so far. Past successful community experiences, as well as a proven conceptual framework, were used to help establish community partnerships and governance structures, as well as to demonstrate their linkages. This paper represents a compilation of reports and information from key Beacon leaders, staff and providers and their firsthand experiences in setting up those structures, as well as their conclusions. The community partnerships proved extremely successful in not only devising successful ways to introduce new technology into healthcare settings, but in sustaining those changes by creating a governance structure that has enough fluidity to adapt to changing circumstances. Building and developing community partnerships takes time and effort; however, these relationships are necessary and essential to introducing and sustaining new technologies in a healthcare setting and should be a first step for any organization looking to accomplish such goals.

  1. Application of cytoplasmic Ca2+ fluorescence imaging techniques to study the molecular mechanisms of exercise-induced fatigue eliminated by Chinese medicine ginseng extract

    Science.gov (United States)

    Liu, Yi; Zhao, Yanping; Zhang, Heming; Liu, Songhao

    2009-11-01

    The exercise-induced fatigue eliminated by Chinese medicine offers advantages including good efficiency and smaller side-effects, however, the exact mechanisms have not been classified. A lot of literatures indicated the cytosolic free Ca2+ concentrations of skeletal muscle cells increased significantly during exercise-induced fatigue. This study is aimed to establish a rat skeletal muscle cell model of exercise-induced fatigue. We applied cytoplasmic Ca2+ fluorescence imaging techniques to study the molecular mechanisms of exercise-induced fatigue eliminated by Chinese medicine ginseng extract. In our research, the muscle tissues from the newborn 3 days rats were taken out and digested into cells. The cells were randomly divided into the ginseng extract group and the control group. The cells from the two groups were cultured in the medium respectively added 2mg/ml ginseng extract and 2mg/ml D-hanks solution. After differentiating into myotubes, the two groups of cells treated with a fluorescent probe Fluo-3 AM were put on the confocal microscope and the fluorescence intensity of cells pre- and post- stimulation with dexamethasone were detected. It was found that cytoplasmic Ca2+ concentrations of the two groups of cells both increased post-stimulation, however, the increasing amplitude of fluorescence intensity of the ginseng extract group was significantly lower than that of the control group. In conclusion, stimulating the cells with dexamethasone is a kind of workable cell models of exercise-induced fatigue, and the molecular mechanisms of exercise-induced fatigue eliminated by ginseng extract may be connected to regulatating cytosolic free Ca2+ concentrations.

  2. Use of Spectroscopic, Zeta Potential and Molecular Dynamic Techniques to Study the Interaction between Human Holo-Transferrin and Two Antagonist Drugs: Comparison of Binary and Ternary Systems

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Saberi

    2012-03-01

    Full Text Available For the first time, the binding of ropinirole hydrochloride (ROP and aspirin (ASA to human holo-transferrin (hTf has been investigated by spectroscopic approaches (fluorescence quenching, synchronous fluorescence, time-resolved fluorescence, three-dimensional fluorescence, UV-vis absorption, circular dichroism, resonance light scattering, as well as zeta potential and molecular modeling techniques, under simulated physiological conditions. Fluorescence analysis was used to estimate the effect of the ROP and ASA drugs on the fluorescence of hTf as well as to define the binding and quenching properties of binary and ternary complexes. The synchronized fluorescence and three-dimensional fluorescence spectra demonstrated some micro-environmental and conformational changes around the Trp and Tyr residues with a faint red shift. Thermodynamic analysis displayed the van der Waals forces and hydrogen bonds interactions are the major acting forces in stabilizing the complexes. Steady-state and time-resolved fluorescence data revealed that the fluorescence quenching of complexes are static mechanism. The effect of the drugs aggregating on the hTf resulted in an enhancement of the resonance light scattering (RLS intensity. The average binding distance between were computed according to the forster non-radiation energy transfer theory. The circular dichroism (CD spectral examinations indicated that the binding of the drugs induced a conformational change of hTf. Measurements of the zeta potential indicated that the combination of electrostatic and hydrophobic interactions between ROP, ASA and hTf formed micelle-like clusters. The molecular modeling confirmed the experimental results. This study is expected to provide important insight into the interaction of hTf with ROP and ASA to use in various toxicological and therapeutic processes.

  3. Implications of recent research on microstructure modifications, through heat-related processing and trait alteration to bio-functions, molecular thermal stability and mobility, metabolic characteristics and nutrition in cool-climate cereal grains and other types of seeds with advanced molecular techniques.

    Science.gov (United States)

    Ying, Yuguang; Zhang, Huihua; Yu, Peiqiang

    2018-02-16

    The cutting-edge synchrotron radiation based and globar-sourced vibrational infrared microspectroscopy have recently been developed. These novel techniques are able to reveal structure features at cellular and molecular levels with the tested tissues being intact. However, to date, the advanced techniques are unfamiliar or unknown to food and feed scientists and have not been used to study the molecular structure changes in cool-climate cereal grain seeds and other types of bio-oil and bioenergy seeds. This article aims to provide some recent research in cool-climate cereal grains and other types of seeds on molecular structures and metabolic characteristics of carbohydrate and protein, and implication of microstructure modification through heat-related processing and trait alteration to bio-functions, molecular thermal stability and mobility, and nutrition with advanced molecular techniques- synchrotron radiation based and globar-sourced vibrational infrared microspectroscopy in the areas of (1) Inherent microstructure of cereal grain seeds; (2) The nutritional values of cereal grains; (3) Impact and modification of heat-related processing to cereal grain; (4) Conventional nutrition evaluation methodology; (5) Synchrotron radiation-based and globar-sourced vibrational (micro)-spectroscopy for molecular structure study and molecular thermal stability and mobility, and (6) Recent molecular spectroscopic technique applications in research on raw, traits altered and processed cool-climate cereal grains and other types of seeds. The information described in this article gives better insights of research progress and update in cool-climate cereal grains and other seeds with advanced molecular techniques.

  4. Microbial and molecular techniques to evaluate and to implement in-situ biodegradation potential and activity at sites contaminated with aromatic and chlorinated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Karg, F. [HPC Envirotec / France and HPC AG (Germany); Henkler, Ch. [Planreal (Switzerland)

    2005-07-01

    Intrinsic bio-remediation harnesses the ability of indigenous microorganisms to degrade contaminants that are present in soil and groundwater. Over the past decade many environmental regulatory agencies especially in Europe have come to recognize the importance of these natural processes in contaminant attenuation. In order to use in-situ bio-remediation to clean up a site successfully it is necessary to investigate the indigenous microbial population and its potential activity to degrade the contaminants of concern (COCs). The evaluation of naturally-occurring degradative activity in initial screening of soil and groundwater samples using recently developed molecular and microbial methods may allow for the implementation of a contaminant reduction and management program without the need for fully engineered remediation intervention. Limited engineering approaches (nutrient delivery etc.) can be implemented to support naturally-occurring bio-restoration processes to achieve a controlled, dynamic attenuation of COCs. Techniques for monitoring pollutant-degrading microorganisms were previously limited to standard culturing techniques. More recently, techniques based upon detection of genetic elements and metabolic activities have been developed in collaboration with university partners Europe, especially in France. The modern techniques are more sensitive for monitoring microbial populations, metabolic activity and the genetic potential to degrade the COCs, and avoid the need for cultivation of microbes under artificial conditions in the laboratory. Especially the application of PCR-Tests (Polymerase Chain Reaction) are able to quantify the Genetic Potential of Pollutant Microbiological Degradation on a contaminated site. This enables to use very economic in-situ site rehabilitation strategies as for example (Dynamic Natural Attenuation). For this modern application of these new strategies PLANREAL created with HPC Envirotec and together with a French University

  5. Microbial and molecular techniques to evaluate and to implement in-situ biodegradation potential and activity at sites contaminated with aromatic and chlorinated hydrocarbons

    International Nuclear Information System (INIS)

    Karg, F.; Henkler, Ch.

    2005-01-01

    Intrinsic bio-remediation harnesses the ability of indigenous microorganisms to degrade contaminants that are present in soil and groundwater. Over the past decade many environmental regulatory agencies especially in Europe have come to recognize the importance of these natural processes in contaminant attenuation. In order to use in-situ bio-remediation to clean up a site successfully it is necessary to investigate the indigenous microbial population and its potential activity to degrade the contaminants of concern (COCs). The evaluation of naturally-occurring degradative activity in initial screening of soil and groundwater samples using recently developed molecular and microbial methods may allow for the implementation of a contaminant reduction and management program without the need for fully engineered remediation intervention. Limited engineering approaches (nutrient delivery etc.) can be implemented to support naturally-occurring bio-restoration processes to achieve a controlled, dynamic attenuation of COCs. Techniques for monitoring pollutant-degrading microorganisms were previously limited to standard culturing techniques. More recently, techniques based upon detection of genetic elements and metabolic activities have been developed in collaboration with university partners Europe, especially in France. The modern techniques are more sensitive for monitoring microbial populations, metabolic activity and the genetic potential to degrade the COCs, and avoid the need for cultivation of microbes under artificial conditions in the laboratory. Especially the application of PCR-Tests (Polymerase Chain Reaction) are able to quantify the Genetic Potential of Pollutant Microbiological Degradation on a contaminated site. This enables to use very economic in-situ site rehabilitation strategies as for example (Dynamic Natural Attenuation). For this modern application of these new strategies PLANREAL created with HPC Envirotec and together with a French University

  6. A Molecular Method to Discriminate between Mass-Reared Sterile and Wild Tsetse Flies during Eradication Programmes That Have a Sterile Insect Technique Component.

    Directory of Open Access Journals (Sweden)

    Soumaïla Pagabeleguem

    2016-02-01

    Full Text Available The Government of Senegal has embarked several years ago on a project that aims to eradicate Glossina palpalis gambiensis from the Niayes area. The removal of the animal trypanosomosis would allow the development more efficient livestock production systems. The project was implemented using an area-wide integrated pest management strategy including a sterile insect technique (SIT component. The released sterile male flies originated from a colony from Burkina Faso.Monitoring the efficacy of the sterile male releases requires the discrimination between wild and sterile male G. p. gambiensis that are sampled in monitoring traps. Before being released, sterile male flies were marked with a fluorescent dye powder. The marking was however not infallible with some sterile flies only slightly marked or some wild flies contaminated with a few dye particles in the monitoring traps. Trapped flies can also be damaged due to predation by ants, making it difficult to discriminate between wild and sterile males using a fluorescence camera and / or a fluorescence microscope. We developed a molecular technique based on the determination of cytochrome oxidase haplotypes of G. p. gambiensis to discriminate between wild and sterile males. DNA was isolated from the head of flies and a portion of the 5' end of the mitochondrial gene cytochrome oxidase I was amplified to be finally sequenced. Our results indicated that all the sterile males from the Burkina Faso colony displayed the same haplotype and systematically differed from wild male flies trapped in Senegal and Burkina Faso. This allowed 100% discrimination between sterile and wild male G. p. gambiensis.This tool might be useful for other tsetse control campaigns with a SIT component in the framework of the Pan-African Tsetse and Trypanosomosis Eradication Campaign (PATTEC and, more generally, for other vector or insect pest control programs.

  7. A conformational NMR analysis of methymycin aglycones: complete and unambiguous assignments of stereochemically diverse glycosylated methymycin analogs by 1D and 2D NMR techniques and molecular modeling.

    Science.gov (United States)

    Akhmedov, Novruz G; Gannett, Peter M; Wu, Bulan; Cummings, Matthew M; Train, Brian C

    2013-03-01

    The (1)H and (13)C NMR spectra of 10-deoxymethynolide (1), 8.9-dihydro-10-deoxymethynolide (2) and its glycosylated derivatives (3-9) were analyzed using gradient-selected NMR techniques, including 1D TOCSY, gCOSY, 1D NOESY (DPFGSENOE), NOESY, gHMBC, gHSQC and gHSQC-TOCSY. The NMR spectral parameters (chemical shifts and coupling constants) of 1-9 were determined by iterative analysis. For the first time, complete and unambiguous assignment of the (1)H NMR spectrum of 10-deoxymethynolide (1) has been achieved in CDCl(3), CD(3)OD and C(6)D(6) solvents. The (1)H NMR spectrum of 8,9-dihydro-10-deoxymethynolide (2) was recorded in CDCl(3), (CD(3))(2)CO and CD(3)OD solutions to determine the conformation. NMR-based conformational analysis of 1 and 2 in conjugation with molecular modeling concluded that the 12-membered ring of the macrolactones may predominantly exist in a single stable conformation in all solvents examined. In all cases, a change in solvent caused only small changes in chemical shifts and coupling constants, suggesting that all glycosylated methymycin analogs exist with similar conformations of the aglycone ring in solution. Copyright © 2013 John Wiley & Sons, Ltd.

  8. Pressure-induced metallization of condensed phase β-HMX under shock loadings via molecular dynamics simulations in conjunction with multi-scale shock technique.

    Science.gov (United States)

    Ge, Ni-Na; Wei, Yong-Kai; Zhao, Feng; Chen, Xiang-Rong; Ji, Guang-Fu

    2014-07-01

    The electronic structure and initial decomposition in high explosive HMX under conditions of shock loading are examined. The simulation is performed using quantum molecular dynamics in conjunction with multi-scale shock technique (MSST). A self-consistent charge density-functional tight-binding (SCC-DFTB) method is adapted. The results show that the N-N-C angle has a drastic change under shock wave compression along lattice vector b at shock velocity 11 km/s, which is the main reason that leads to an insulator-to-metal transition for the HMX system. The metallization pressure (about 130 GPa) of condensed-phase HMX is predicted firstly. We also detect the formation of several key products of condensed-phase HMX decomposition, such as NO2, NO, N2, N2O, H2O, CO, and CO2, and all of them have been observed in previous experimental studies. Moreover, the initial decomposition products include H2 due to the C-H bond breaking as a primary reaction pathway at extreme condition, which presents a new insight into the initial decomposition mechanism of HMX under shock loading at the atomistic level.

  9. Comprehensive Peptide Ion Structure Studies Using Ion Mobility Techniques: Part 1. An Advanced Protocol for Molecular Dynamics Simulations and Collision Cross-Section Calculation

    Science.gov (United States)

    Ghassabi Kondalaji, Samaneh; Khakinejad, Mahdiar; Tafreshian, Amirmahdi; J. Valentine, Stephen

    2017-05-01

    Collision cross-section (CCS) measurements with a linear drift tube have been utilized to study the gas-phase conformers of a model peptide (acetyl-PAAAAKAAAAKAAAAKAAAAK). Extensive molecular dynamics (MD) simulations have been conducted to derive an advanced protocol for the generation of a comprehensive pool of in-silico structures; both higher energy and more thermodynamically stable structures are included to provide an unbiased sampling of conformational space. MD simulations at 300 K are applied to the in-silico structures to more accurately describe the gas-phase transport properties of the ion conformers including their dynamics. Different methods used previously for trajectory method (TM) CCS calculation employing the Mobcal software [1] are evaluated. A new method for accurate CCS calculation is proposed based on clustering and data mining techniques. CCS values are calculated for all in-silico structures, and those with matching CCS values are chosen as candidate structures. With this approach, more than 300 candidate structures with significant structural variation are produced; although no final gas-phase structure is proposed here, in a second installment of this work, gas-phase hydrogen deuterium exchange data will be utilized as a second criterion to select among these structures as well as to propose relative populations for these ion conformers. Here the need to increase conformer diversity and accurate CCS calculation is demonstrated and the advanced methods are discussed.

  10. Anisotropic responses and initial decomposition of condensed-phase β-HMX under shock loadings via molecular dynamics simulations in conjunction with multiscale shock technique.

    Science.gov (United States)

    Ge, Ni-Na; Wei, Yong-Kai; Song, Zhen-Fei; Chen, Xiang-Rong; Ji, Guang-Fu; Zhao, Feng; Wei, Dong-Qing

    2014-07-24

    Molecular dynamics simulations in conjunction with multiscale shock technique (MSST) are performed to study the initial chemical processes and the anisotropy of shock sensitivity of the condensed-phase HMX under shock loadings applied along the a, b, and c lattice vectors. A self-consistent charge density-functional tight-binding (SCC-DFTB) method was employed. Our results show that there is a difference between lattice vector a (or c) and lattice vector b in the response to a shock wave velocity of 11 km/s, which is investigated through reaction temperature and relative sliding rate between adjacent slipping planes. The response along lattice vectors a and c are similar to each other, whose reaction temperature is up to 7000 K, but quite different along lattice vector b, whose reaction temperature is only up to 4000 K. When compared with shock wave propagation along the lattice vectors a (18 Å/ps) and c (21 Å/ps), the relative sliding rate between adjacent slipping planes along lattice vector b is only 0.2 Å/ps. Thus, the small relative sliding rate between adjacent slipping planes results in the temperature and energy under shock loading increasing at a slower rate, which is the main reason leading to less sensitivity under shock wave compression along lattice vector b. In addition, the C-H bond dissociation is the primary pathway for HMX decomposition in early stages under high shock loading from various directions. Compared with the observation for shock velocities V(imp) = 10 and 11 km/s, the homolytic cleavage of N-NO2 bond was obviously suppressed with increasing pressure.

  11. Exploring the multiscale signaling behavior of phototropin1 from Chlamydomonas reinhardtii using a full-residue space kinetic Monte Carlo molecular dynamics technique.

    Science.gov (United States)

    Peter, Emanuel; Dick, Bernhard; Stambolic, Ivan; Baeurle, Stephan A

    2014-09-01

    Devising analysis tools for elucidating the regulatory mechanism of complex enzymes has been a challenging task for many decades. It generally requires the determination of the structural-dynamical information of protein solvent systems far from equilibrium over multiple length and time scales, which is still difficult both theoretically and experimentally. To cope with the problem, we introduce a full-residue space multiscale simulation method based on a combination of the kinetic Monte Carlo and molecular dynamics techniques, in which the rates of the rate-determining processes are evaluated from a biomolecular forcefield on the fly during the simulation run by taking into account the full space of residues. To demonstrate its reliability and efficiency, we explore the light-induced functional behavior of the full-length phototropin1 from Chlamydomonas reinhardtii (Cr-phot1) and its various subdomains. Our results demonstrate that in the dark state the light oxygen voltage-2-Jα (LOV2-Jα) photoswitch inhibits the enzymatic activity of the kinase, whereas the LOV1-Jα photoswitch controls the dimerization with the LOV2 domain. This leads to the repulsion of the LOV1-LOV2 linker out of the interface region between both LOV domains, which results in a positively charged surface suitable for cell-membrane interaction. By contrast, in the light state, we observe that the distance between both LOV domains is increased and the LOV1-LOV2 linker forms a helix-turn-helix (HTH) motif, which enables gene control through nucleotide binding. Finally, we find that the kinase is activated through the disruption of the Jα-helix from the LOV2 domain, which is followed by a stretching of the activation loop (A-loop) and broadening of the catalytic cleft of the kinase. © 2014 Wiley Periodicals, Inc.

  12. Combining vibrational biomolecular spectroscopy with chemometric techniques for the study of response and sensitivity of molecular structures/functional groups mainly related to lipid biopolymer to various processing applications.

    Science.gov (United States)

    Yu, Gloria Qingyu; Yu, Peiqiang

    2015-09-01

    The objectives of this project were to (1) combine vibrational spectroscopy with chemometric multivariate techniques to determine the effect of processing applications on molecular structural changes of lipid biopolymer that mainly related to functional groups in green- and yellow-type Crop Development Centre (CDC) pea varieties [CDC strike (green-type) vs. CDC meadow (yellow-type)] that occurred during various processing applications; (2) relatively quantify the effect of processing applications on the antisymmetric CH3 ("CH3as") and CH2 ("CH2as") (ca. 2960 and 2923 cm(-1), respectively), symmetric CH3 ("CH3s") and CH2 ("CH2s") (ca. 2873 and 2954 cm(-1), respectively) functional groups and carbonyl C=O ester (ca. 1745 cm(-1)) spectral intensities as well as their ratios of antisymmetric CH3 to antisymmetric CH2 (ratio of CH3as to CH2as), ratios of symmetric CH3 to symmetric CH2 (ratio of CH3s to CH2s), and ratios of carbonyl C=O ester peak area to total CH peak area (ratio of C=O ester to CH); and (3) illustrate non-invasive techniques to detect the sensitivity of individual molecular functional group to the various processing applications in the recently developed different types of pea varieties. The hypothesis of this research was that processing applications modified the molecular structure profiles in the processed products as opposed to original unprocessed pea seeds. The results showed that the different processing methods had different impacts on lipid molecular functional groups. Different lipid functional groups had different sensitivity to various heat processing applications. These changes were detected by advanced molecular spectroscopy with chemometric techniques which may be highly related to lipid utilization and availability. The multivariate molecular spectral analyses, cluster analysis, and principal component analysis of original spectra (without spectral parameterization) are unable to fully distinguish the structural differences in the

  13. Efficacy and safety of QVA149 compared to the concurrent administration of its monocomponents indacaterol and glycopyrronium: the BEACON study

    Directory of Open Access Journals (Sweden)

    Dahl R

    2013-10-01

    Full Text Available Ronald Dahl,1 Dalal Jadayel,2 Vijay KT Alagappan,3 Hungta Chen,3 Donald Banerji31Department of Dermatology, Allergy Centre, Odense University Hospital, Odense, Denmark; 2Novartis Horsham Research Centre, Horsham, UK; 3Novartis Pharmaceuticals Corporation, East Hanover, NJ, USAIntroduction: The BEACON study evaluated the efficacy and safety of QVA149, a once-daily dual bronchodilator containing a fixed-dose combination of the long-acting β2-agonist (LABA indacaterol and long-acting muscarinic antagonist (LAMA glycopyrronium (NVA237, in development for the treatment of patients with chronic obstructive pulmonary disease (COPD, compared with the free-dose concurrent administration of indacaterol plus glycopyrronium (IND+GLY.Methods: In this multicenter, double-blind, parallel group study, patients with stage II or stage III COPD (Global initiative for chronic Obstructive Lung Disease [GOLD] 2010 were randomized (1:1 to once-daily QVA149 (110 µg indacaterol/50 µg glycopyrronium or concurrent administration of indacaterol (150 µg and glycopyrronium (50 µg via the Breezhaler® device (Novartis AG, Basel, Switzerland for 4 weeks. The primary endpoint was to evaluate the noninferiority of QVA149 as compared with concurrent administration of IND+GLY, for trough forced expiratory volume in 1 second (FEV1 after 4 weeks of treatment. The other assessments included FEV1 area under the curve from 0 to 4 hours (AUC0–4 hours at day 1 and week 4, symptom scores, rescue medication use, safety, and tolerability over the 4-week study period.Results: Of 193 patients randomized, 187 (96.9% completed the study. Trough FEV1 at week 4 for QVA149 and IND+GLY was 1.46 L ± 0.02 and 1.46 L ± 0.18, respectively. The FEV1 AUC0–4 hours at day 1 and week 4 were similar between the two treatment groups. Both treatment groups had a similar reduction in symptom scores and rescue medication use for the 4-week treatment period. Overall, 25.6% of patients in QVA149 group

  14. What Bacteria Are Living in My Food?: An Open-Ended Practical Series Involving Identification of Unknown Foodborne Bacteria Using Molecular Techniques

    Science.gov (United States)

    Prasad, Prascilla; Turner, Mark S.

    2011-01-01

    This open-ended practical series titled "Molecular Identification of Unknown Food Bacteria" which extended over a 6-week period was designed with the aims of giving students an opportunity to gain an understanding of naturally occurring food bacteria and skills in contemporary molecular methods using real food samples. The students first isolated…

  15. Development and optimisation of a novel three-way extraction technique based on a combination of Soxhlet extraction, membrane assisted solvent extraction and a molecularly imprinted polymer using sludge polycyclic aromatic hydrocarbons as model compounds.

    Science.gov (United States)

    Ncube, Somandla; Lekoto, Goitsemang; Cukrowska, Ewa; Chimuka, Luke

    2018-02-01

    A novel technique that integrates extraction and clean-up into a single step format is reported as part of the search for new sample preparation techniques in the analysis of persistent organic pollutants from complex samples. This was achieved by combining the extraction efficiency of the Soxhlet extractor, the selectivity of a size exclusion membrane and the specificity of a molecularly imprinted polymer for the extraction of polycyclic aromatic hydrocarbons from wastewater sludge followed by quantitation using gas chromatography with time-of-flight mass spectrometry. The approach is described as the Soxhlet extraction membrane-assisted solvent extraction molecularly imprinted polymer technique. This technique was optimised for various parameters such as extraction solvent, reflux time and membrane acceptor phase. The applicability of the developed technique was optimised using a wastewater sludge certified reference material and then tested on real wastewater sludge samples. The method detection limits ranged from 0.14 to 12.86 ng/g with relative standard deviation values for the extraction of the 16 US-EPA priority polycyclic aromatic hydrocarbons from wastewater sludge samples ranging from 0.78 to 18%. The extraction process was therefore reproducible and showed remarkable selectivity. The developed technique is a promising prospect that can be applied in the analysis of organic pollutants from complex solid samples. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Location-Enhanced Activity Recognition in Indoor Environments Using Off the Shelf Smart Watch Technology and BLE Beacons.

    Science.gov (United States)

    Filippoupolitis, Avgoustinos; Oliff, William; Takand, Babak; Loukas, George

    2017-05-27

    Activity recognition in indoor spaces benefits context awareness and improves the efficiency of applications related to personalised health monitoring, building energy management, security and safety. The majority of activity recognition frameworks, however, employ a network of specialised building sensors or a network of body-worn sensors. As this approach suffers with respect to practicality, we propose the use of commercial off-the-shelf devices. In this work, we design and evaluate an activity recognition system composed of a smart watch, which is enhanced with location information coming from Bluetooth Low Energy (BLE) beacons. We evaluate the performance of this approach for a variety of activities performed in an indoor laboratory environment, using four supervised machine learning algorithms. Our experimental results indicate that our location-enhanced activity recognition system is able to reach a classification accuracy ranging from 92% to 100%, while without location information classification accuracy it can drop to as low as 50% in some cases, depending on the window size chosen for data segmentation.

  17. Location-Enhanced Activity Recognition in Indoor Environments Using Off the Shelf Smart Watch Technology and BLE Beacons

    Directory of Open Access Journals (Sweden)

    Avgoustinos Filippoupolitis

    2017-05-01

    Full Text Available Activity recognition in indoor spaces benefits context awareness and improves the efficiency of applications related to personalised health monitoring, building energy management, security and safety. The majority of activity recognition frameworks, however, employ a network of specialised building sensors or a network of body-worn sensors. As this approach suffers with respect to practicality, we propose the use of commercial off-the-shelf devices. In this work, we design and evaluate an activity recognition system composed of a smart watch, which is enhanced with location information coming from Bluetooth Low Energy (BLE beacons. We evaluate the performance of this approach for a variety of activities performed in an indoor laboratory environment, using four supervised machine learning algorithms. Our experimental results indicate that our location-enhanced activity recognition system is able to reach a classification accuracy ranging from 92% to 100%, while without location information classification accuracy it can drop to as low as 50% in some cases, depending on the window size chosen for data segmentation.

  18. Meeting Report: ALTER-Net Workshop about the Application of Molecular Techniques to Study Biodiversity, Structure and Function of Planktonic Communities in Lakes at Blanes, Spain, February 15–16, 2007

    Czech Academy of Sciences Publication Activity Database

    Groben, R.; Hahn, M.W.; Horňák, Karel; Mergeay, J.; Šimek, Karel; Vrba, Jaroslav

    2007-01-01

    Roč. 158, č. 4 (2007), s. 417-421 ISSN 1434-4610 Grant - others:EU(XE) GOCE-CT-2003-505298 Institutional research plan: CEZ:AV0Z60170517 Source of funding: R - rámcový projekt EK Keywords : ALTER-Net * molecular techniques * biodiversity * planktonic communities * lakes Subject RIV: EH - Ecology, Behaviour Impact factor: 3.102, year: 2007

  19. Molecular modeling

    Directory of Open Access Journals (Sweden)

    Aarti Sharma

    2009-01-01

    Full Text Available The use of computational chemistry in the development of novel pharmaceuticals is becoming an increasingly important tool. In the past, drugs were simply screened for effectiveness. The recent advances in computing power and the exponential growth of the knowledge of protein structures have made it possible for organic compounds to be tailored to decrease the harmful side effects and increase the potency. This article provides a detailed description of the techniques employed in molecular modeling. Molecular modeling is a rapidly developing discipline, and has been supported by the dramatic improvements in computer hardware and software in recent years.

  20. Molecular fountain.

    Energy Technology Data Exchange (ETDEWEB)

    Strecker, Kevin E.; Chandler, David W.

    2009-09-01

    A molecular fountain directs slowly moving molecules against gravity to further slow them to translational energies that they can be trapped and studied. If the molecules are initially slow enough they will return some time later to the position from which they were launched. Because this round trip time can be on the order of a second a single molecule can be observed for times sufficient to perform Hz level spectroscopy. The goal of this LDRD proposal was to construct a novel Molecular Fountain apparatus capable of producing dilute samples of molecules at near zero temperatures in well-defined user-selectable, quantum states. The slowly moving molecules used in this research are produced by the previously developed Kinematic Cooling technique, which uses a crossed atomic and molecular beam apparatus to generate single rotational level molecular samples moving slowly in the laboratory reference frame. The Kinematic Cooling technique produces cold molecules from a supersonic molecular beam via single collisions with a supersonic atomic beam. A single collision of an atom with a molecule occurring at the correct energy and relative velocity can cause a small fraction of the molecules to move very slowly vertically against gravity in the laboratory. These slowly moving molecules are captured by an electrostatic hexapole guiding field that both orients and focuses the molecules. The molecules are focused into the ionization region of a time-of-flight mass spectrometer and are ionized by laser radiation. The new molecular fountain apparatus was built utilizing a new design for molecular beam apparatus that has allowed us to miniaturize the apparatus. This new design minimizes the volumes and surface area of the machine allowing smaller pumps to maintain the necessary background pressures needed for these experiments.

  1. Identificação de variantes somaclonais em bananeiras 'Prata Anã', utilizando técnicas moleculares e citogenéticas Identification of somaclonal variants in 'Prata Anã' banana using molecular and cytogenetic techniques

    Directory of Open Access Journals (Sweden)

    Nilson César Castanheira Guimarães

    2009-04-01

    generations to follow, or of epigenetic origin, in this case being a transitory variation due to the physiological stress suffered when the material is submitted to in vitro cultivation. A specific problem involving somaclonal variation in 'Prata Anã' banana was observed in Andradas, Minas Gerais, in plants originated from tissue culture. The main difficulty in the distinction between the normal and variant plants is the fact that the morphological characters that allow the separation of these two types are only visible and distinguishable when the plants are in their adult phase, which makes it impossible to eliminate the variant seedlings at the nursery stage. For the early distinction of the variants, molecular (RAPD - Random Amplified Polymorphic DNA and SSR - Simple Sequence Repeat and cytogenetic (chromosome counting and flow cytometry techniques were used. In the attempt to find polymorphic markers that distinguished the normal plants from the variants as well as the Prata cultivar from the Prata Anã cultivar, 103 RAPD primers, 11 combinations of two RAPD primers, and 33 pairs of SSR primers were used. Primer OPW-08 generated a polymorphic fragment that distinguished a variant from all of the other plants, proving that the variation does not occur uniformly in the genome of all variants, and that there is no return to Prata cultivar. Analyses with SSR markers and chromosome counting were not efficient in separating normal plants from variants or 'Prata' from 'Prata Anã'. Flow cytometry analyses showed an evident instability in the banana genome in terms of number of chromosomes, however, they were not efficient in identifying the somaclonal variants.

  2. Técnicas de caracterização para investigar interações no nível molecular em filmes de Langmuir e Langmuir-Blodgett (LB Characterization techniques to investigate molecular-level interactions in Langmuir and Langmuir-Blodgett (LB films

    Directory of Open Access Journals (Sweden)

    Marystela Ferreira

    2005-06-01

    Full Text Available This paper discusses fundamental concepts for the characterization of Langmuir monolayers and Langmuir-Blodgett (LB films, with emphasis on investigations of material properties at the molecular level. By way of illustration, results for phospholipid monolayers interacting with the drug dipyridamole are highlighted. These results were obtained with several techniques, including in situ grazing incidence X-ray diffraction, Fourier transform infrared (FTIR spectroscopy, fluorescence microscopy, in addition to surface pressure and surface potential isotherms. Also mentioned are the difficulties in producing Langmuir and LB films from macromolecules, and how molecular-level interactions in mixed polymer LB films can be exploited in sensors.

  3. Characterization of the molecular distribution of drugs in glassy solid dispersions at the nano-meter scale, using differential scanning calorimetry and gravimetric water vapour sorption techniques

    NARCIS (Netherlands)

    van Drooge, D J; Hinrichs, W L J; Visser, M R; Frijlink, H W

    2006-01-01

    The molecular distribution in fully amorphous solid dispersions consisting of poly(vinylpyrrolidone) (PVP)-diazepam and inulin-diazepam was studied. One glass transition temperature (T-g), as determined by temperature modulated differential scanning calorimetry (TMDSC), was observed in PVP-diazepam

  4. Physiological Monitoring of a Wrist-Worn Personal Locator Beacon User

    Directory of Open Access Journals (Sweden)

    Alejandro DE MIQUEL

    2016-11-01

    Full Text Available This paper presents the concept, developments and preliminary results of the Horizon 2020 project named SAT406M. The goal of this project is to develop an application based on a wrist-worn device, conceived to be a maritime application, and the use of European Global Navigation Satellite Systems, based on the Galileo Search and Rescue service, using its unique Return-Link-Message function, improving the mobility and safety of citizens. In particular for this paper, we focus on the development and the first testing and results of a physiological monitoring component included in the device. This component will provide the Search and Rescue services with additional information about the SAT406M user's physiological status once the distress alarm is triggered. The algorithm implemented uses some stochastic techniques to deduce the SAT406M user's physiological status, encoded in two bits, from sensor inputs. The results here presented, which are still preliminary results from an intermediate stage of the project, show a good accuracy in most of the cases. This makes us conclude that the algorithm has the potential to end up determining the SAT406M user's physiological status accurately enough, improving this way the user's safety.

  5. A Novel 3D Multilateration Sensor Using Distributed Ultrasonic Beacons for Indoor Navigation

    Directory of Open Access Journals (Sweden)

    Rohan Kapoor

    2016-10-01

    Full Text Available Navigation and guidance systems are a critical part of any autonomous vehicle. In this paper, a novel sensor grid using 40 KHz ultrasonic transmitters is presented for adoption in indoor 3D positioning applications. In the proposed technique, a vehicle measures the arrival time of incoming ultrasonic signals and calculates the position without broadcasting to the grid. This system allows for conducting silent or covert operations and can also be used for the simultaneous navigation of a large number of vehicles. The transmitters and receivers employed are first described. Transmission lobe patterns and receiver directionality determine the geometry of transmitter clusters. Range and accuracy of measurements dictate the number of sensors required to navigate in a given volume. Laboratory experiments were performed in which a small array of transmitters was set up and the sensor system was tested for position accuracy. The prototype system is shown to have a 1-sigma position error of about 16 cm, with errors between 7 and 11 cm in the local horizontal coordinates. This research work provides foundations for the future development of ultrasonic navigation sensors for a variety of autonomous vehicle applications.

  6. Cardiovascular molecular MR imaging

    OpenAIRE

    Lamb, H. J.; van der Meer, R. W.; de Roos, A.; Bax, J. J.

    2007-01-01

    Introduction Cardiovascular molecular imaging is a rapidly evolving field of research, aiming to image and quantify molecular and cellular targets in vivo. MR imaging has some inherent properties that make it very suitable for cardiovascular molecular imaging. Until now, only a limited number of studies have been published on cardiovascular molecular imaging using MR imaging. Review In the current review, MR techniques that have already shown potential are discussed. Metabolic MR imaging can ...

  7. A Semester-Long Project for Teaching Basic Techniques in Molecular Biology Such as Restriction Fragment Length Polymorphism Analysis to Undergraduate and Graduate Students

    OpenAIRE

    DiBartolomeis, Susan M.

    2011-01-01

    Several reports on science education suggest that students at all levels learn better if they are immersed in a project that is long term, yielding results that require analysis and interpretation. I describe a 12-wk laboratory project suitable for upper-level undergraduates and first-year graduate students, in which the students molecularly locate and map a gene from Drosophila melanogaster called dusky and one of dusky's mutant alleles. The mapping strategy uses restriction fragment length ...

  8. Alimentary Tract Bacteria Isolated and Identified with API-20E and Molecular Cloning Techniques from Australian Tropical Fruit Flies, Bactrocera cacuminata and B. tryoni

    OpenAIRE

    Thaochan, N.; Drew, R. A. I.; Hughes, J. M.; Vijaysegaran, S.; Chinajariyawong, A.

    2010-01-01

    Bacteria were isolated from the crop and midgut of field collected Bactrocera cacuminata (Hering) and Bactrocera tryoni (Froggatt) (Diptera: Tephritidae). Two methods were used, firstly isolation onto two types of bacteriological culture media (PYEA and TSA) and identification using the API-20E diagnostic kit, and secondly, analysis of samples using the 16S rRNA gene molecular diagnostic method. Using the API-20E method, 10 genera and 17 species of bacteria in the family Enterobacteriaceae we...

  9. Quantitative molecular and culture analyses of bacterial elimination in oval-shaped root canals by a single-file instrumentation technique.

    Science.gov (United States)

    Alves, F R F; Rôças, I N; Almeida, B M; Neves, M A S; Zoffoli, J; Siqueira, J F

    2012-09-01

    Bacterial reduction in oval-shaped root canals by a single-instrument technique was compared ex vivo with a conventional nickel-titanium rotary technique. Data obtained from two quantification methods, quantitative real-time polymerase chain reaction (qPCR) and culture, were also compared. Oval-shaped canals of extracted teeth contaminated with Enterococcus faecalis were instrumented using either a single Reciproc instrument or the BioRaCe instrument series. Bacteriological samples were taken before (S1) and after instrumentation (S2). Bacterial quantification was performed using qPCR and culture. Intragroup analysis showed that both protocols promoted a highly significant bacterial reduction (P 0.05). As for the quantification methods, qPCR revealed significantly higher counts of E. faecalis in S1 than culture (P 0.05). The single-file technique was comparable with the conventional technique in oval-shaped canals provided the width of apical preparation, volume of irrigants and duration of irrigation are kept similar. No significant difference was observed for qPCR and culture in post-instrumentation samples, indicating that both methods can be reliably used for studies of antibacterial effectiveness. © 2012 International Endodontic Journal.

  10. Beyond Blood Culture and Gram Stain Analysis: A Review of Molecular Techniques for the Early Detection of Bacteremia in Surgical Patients.

    Science.gov (United States)

    Scerbo, Michelle H; Kaplan, Heidi B; Dua, Anahita; Litwin, Douglas B; Ambrose, Catherine G; Moore, Laura J; Murray, Col Clinton K; Wade, Charles E; Holcomb, John B

    2016-06-01

    Sepsis from bacteremia occurs in 250,000 cases annually in the United States, has a mortality rate as high as 60%, and is associated with a poorer prognosis than localized infection. Because of these high figures, empiric antibiotic administration for patients with systemic inflammatory response syndrome (SIRS) and suspected infection is the second most common indication for antibiotic administration in intensive care units (ICU)s. However, overuse of empiric antibiotics contributes to the development of opportunistic infections, antibiotic resistance, and the increase in multi-drug-resistant bacterial strains. The current method of diagnosing and ruling out bacteremia is via blood culture (BC) and Gram stain (GS) analysis. Conventional and molecular methods for diagnosing bacteremia were reviewed and compared. The clinical implications, use, and current clinical trials of polymerase chain reaction (PCR)-based methods to detect bacterial pathogens in the blood stream were detailed. BC/GS has several disadvantages. These include: some bacteria do not grow in culture media; others do not GS appropriately; and cultures can require up to 5 d to guide or discontinue antibiotic treatment. PCR-based methods can be potentially applied to detect rapidly, accurately, and directly microbes in human blood samples. Compared with the conventional BC/GS, particular advantages to molecular methods (specifically, PCR-based methods) include faster results, leading to possible improved antibiotic stewardship when bacteremia is not present.

  11. The use of molecular biology techniques for the diagnosis and epidemiological study of foot-and-mouth disease virus in Thailand

    International Nuclear Information System (INIS)

    Linchongsubongkoch, W.; Janukit, T.; Romlumdoan, S.; Phusirimongkol, A.

    2000-01-01

    The detection of foot-and-mouth disease (FMD) virus from various kinds of field samples (tissue extract and cell culture isolate) was studied using the polymerase chain reaction (PCR) technique. The gene selected for diagnosis was the polymerase gene and an amplification target product of 454 bp in length was produced using AP5/AP6 primer sets. The PCR product was further examined by NcoI endonuclease digestion. The presence of the internal restriction site was confirmed by demonstration of two small fragments of 330 bp and 124 bp in length. Forty-nine samples that gave positive and negative results by ELISA typing and were positive by the PCR test were tested by NcoI digestion to confirm the results. About 10% of PCR products could not be confirmed by the method. Furthermore the FMD RNA polymerase gene could be detected by the PCR method in samples negative in both ELISA typing and the virus isolation test. A total of 23 samples were examined and compared after each stage of the testing process. At the end of the extraction for ELISA the amplification product band at 454 bp was detected in 74% of the negative tissue extract samples, and in 48% at the end of the virus isolation procedure. The PCR technique was shown to rapidly and sensitively detect FMD viral genome, when compared with virus titration by tissue culture infectious dose 50% (TCID 50 ) method. The PCR was about 10 times more sensitive than the virus titration technique in detection of virus. Therefore, the PCR technique can be used in conjunction with current procedures for FMD diagnosis, to support the routine standard ELISA typing and virus isolation test on clinical samples. The first step of the nucleotide sequencing technique was introduced with a view to study genomic differentiation of FMD outbreak viruses. The appropriate primer sets for each of the three endemic sero-types were optimized and used to detect the PCR products from field isolate viruses. The PCR products of FMDV type O, A and

  12. Aplicación de las técnicas de biología molecular en oncología oral Application of molecular biology techniques in oral cancer

    OpenAIRE

    M. López-Durán; J. Campo-Trapero; J. Cano-Sánchez; R. Díez-Pérez; A. Bascones-Martínez

    2010-01-01

    Este artículo de revisión se propone exponer las principales técnicas de biología molecular disponibles actualmente para los investigadores, en el campo del cáncer y precáncer oral, clasificadas según el tipo de material biológico del que se disponga para iniciar la investigación. Éste puede ser ADN, ARN o proteínas. La explicación de cada técnica comprenderá una breve sistemática del proceso, así como sus ventajas, inconvenientes y estado de actividad actual. Todo ello con la finalidad de es...

  13. Molecular Modelling

    Directory of Open Access Journals (Sweden)

    Aarti Sharma

    2009-12-01

    Full Text Available

    The use of computational chemistry in the development of novel pharmaceuticals is becoming an increasingly important
    tool. In the past, drugs were simply screened for effectiveness. The recent advances in computing power and
    the exponential growth of the knowledge of protein structures have made it possible for organic compounds to tailored to
    decrease harmful side effects and increase the potency. This article provides a detailed description of the techniques
    employed in molecular modeling. Molecular modelling is a rapidly developing discipline, and has been supported from
    the dramatic improvements in computer hardware and software in recent years.

  14. Intra-molecular mobility of charge carriers along oligogermane backbones studied by flash photolysis time-resolved microwave conductivity and transient optical spectroscopy techniques

    Energy Technology Data Exchange (ETDEWEB)

    Seki, Shu [Division of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)], E-mail: seki@chem.eng.osaka-u.ac.jp; Saeki, Akinori; Acharya, Anjali; Koizumi, Yoshiko; Tagawa, Seiichi [The Institute of Scientific and Industrial Research, Osaka University, 8-1, Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Mochida, Kunio [Department of Chemistry Faculty of Science, Gakusyuin University, 1-5-1 Mejiro, Tokyo 171-8588 (Japan)

    2008-10-15

    Time-resolved microwave conductivity (TRMC) measurement has been performed for fullerene-doped thin films of oligo (dimethylgermane) at different excitation energies to evaluate the intra-molecular mobility of holes along their Ge backbones. Photo-induced electron transfer reaction between oligogermane and fullerene has been observed in the solution with a variety of solvent polarity using transient optical spectroscopy (TOS). The transient spectrum at 391 nm can be attributed to the radical cation of the oligomer under an excitation at 532-nm light, whereas the same spectrum (391 nm) is the overlapping of absorptions of radical cations and neutral radicals of oligogermanes upon exposure of 355-nm light in polar solvent. A combined TRMC and TOS experiments on the solutions of oligomer confirms the conductive transients originate from the radical cations on the backbone chains.

  15. A molecular dynamics investigation of the surface tension of water nanodroplets and a new technique for local pressure determination through density correlation

    Science.gov (United States)

    Leong, Kai-Yang; Wang, Feng

    2018-04-01

    The surface tension of nanoscale droplets of water was studied with molecular dynamics simulations using the BLYPSP-4F water potential. The internal pressure of the droplet was measured using an empirical correlation between the pressure and density, established through a series of bulk simulations performed at pressures from 1 to 1000 bars. Such a procedure allows for reliable determination of internal pressure without the need to calculate the local virial. The surface tension, estimated with the Young-Laplace relation, shows good agreement with the Tolman equation with a Tolman length of -0.48 Å. The interface of a liquid water droplet is shown to be around 1.1-1.3 nm thick depending on radii. The fairly thick interface region puts a lower limit on the size of droplets that still have a bulk-like interior.

  16. Man Overboard Beacon

    National Research Council Canada - National Science Library

    Frank, Thomas A

    2005-01-01

    .... A battery powers the multiple indicators contained in the housing, which include a high intensity strobe light to provide a visual indication, an x-band radar patch antenna to transmit a radar signal...

  17. Beacons of Sound

    DEFF Research Database (Denmark)

    Knakkergaard, Martin

    2018-01-01

    The chapter discusses expectations and imaginations vis-à-vis the concert hall of the twenty-first century. It outlines some of the central historical implications of western culture’s haven for sounding music. Based on the author’s study of the Icelandic concert-house Harpa, the chapter considers...... how these implications, together with the prime mover’s visions, have been transformed as private investors and politicians took over. The chapter furthermore investigates the objectives regarding musical sound and the far-reaching demands concerning acoustics that modern concert halls are required...

  18. Opportunistic Beacon Networks

    NARCIS (Netherlands)

    Türkes, Okan

    2016-01-01

    Modern society is surrounded by an ample spectrum of personal mobile devices with short-range wireless communication support. This ubiquity creates an immense potential of new concepts for people-centric ad hoc networks that can be applied to every personal and social dimension of life. The last

  19. Preparation and evaluation of Exendin radio conjugates for detecting insulinomas and gastrinomas by molecular nuclear medicine techniques; Preparacion y evaluacion de radioconjugados de Exendin para la deteccion de insulinomas y gastrinomas por tecnicas de medicina nuclear molecular

    Energy Technology Data Exchange (ETDEWEB)

    Medina G, V.

    2015-07-01

    The gastro-entero-pancreatic neuroendocrine tumors (GEP-NET) are named based on the secreted hormones. Among them, the insulinomas and gastrinomas represent a diagnostic challenge because of their slow metabolic rate, small size and anatomical location that have limited their detection in some imaging procedures. About 90% of insulinomas are benign and 10% are malignant. Benign insulinomas express the glucagon-like peptide-1 receptor (GLP-1R) and low levels of somatostatin receptors (SSTR), while malignant insulinomas over express SSTR or GLP-1R in low levels. A kit for the preparation of Lys{sup 27} ({sup 99m}Tc-EDDA/HYNIC)-Exendin(9-39)/{sup 99m}Tc-EDDA/HYNIC-Tyr{sup 3}-Octreotide was developed to detect 100% of gastrinomas and insulinomas. In order to reach this aim, the peptides were radiolabeled and characterized. Stability studies will be completed and the in vitro and in vivo behavior was evaluated. The Lys{sup 27}({sup 99m}Tc-EDDA/HYNIC)-Exendin(9-39)/{sup 99m}Tc-EDDA/HYNIC-Tyr{sup 3}-Octreotide can be labeled with {sup 99m}Tc, obtaining high radiochemical purities (>94%), high stability in human serum and affinity to GLP-1 and SST-2 receptor. This new formulation showed properties suitable for use as a target-specific agent for molecular imaging of GLP-1R/SSTR positive tumors. In vivo micro-SPECT/CT images of Lys{sup 27}({sup 99m}Tc-EDDA/HYNIC)-Exendin(9-39), {sup 99m}Tc-EDDA/HYNIC-Tyr{sup 3}-Octreotide and of the pharmaceutical formulation Lys{sup 27}({sup 99m}Tc-EDDA/HYNIC)-Exendin(9-39)/{sup 99m}Tc-EDDA/HYNIC-Tyr{sup 3}-Octreotide showed the main elimination pathways, and tumors higher uptake compared to the background tissues. The biodistribution and imaging studies demonstrated properties suitable for its use as a target-specific agent for the simultaneous molecular imaging of GLP-1R and SSTR. (Author)

  20. Advanced analytical techniques

    International Nuclear Information System (INIS)

    Mrochek, J.E.; Shumate, S.E.; Genung, R.K.; Bahner, C.T.; Lee, N.E.; Dinsmore, S.R.

    1976-01-01

    The development of several new analytical techniques for use in clinical diagnosis and biomedical research is reported. These include: high-resolution liquid chromatographic systems for the early detection of pathological molecular constituents in physiologic body fluids; gradient elution chromatography for the analysis of protein-bound carbohydrates in blood serum samples, with emphasis on changes in sera from breast cancer patients; electrophoretic separation techniques coupled with staining of specific proteins in cellular isoenzymes for the monitoring of genetic mutations and abnormal molecular constituents in blood samples; and the development of a centrifugal elution chromatographic technique for the assay of specific proteins and immunoglobulins in human blood serum samples

  1. Principal component analysis coupled with artificial neural networks--a combined technique classifying small molecular structures using a concatenated spectral database.

    Science.gov (United States)

    Gosav, Steluţa; Praisler, Mirela; Birsa, Mihail Lucian

    2011-01-01

    In this paper we present several expert systems that predict the class identity of the modeled compounds, based on a preprocessed spectral database. The expert systems were built using Artificial Neural Networks (ANN) and are designed to predict if an unknown compound has the toxicological activity of amphetamines (stimulant and hallucinogen), or whether it is a nonamphetamine. In attempts to circumvent the laws controlling drugs of abuse, new chemical structures are very frequently introduced on the black market. They are obtained by slightly modifying the controlled molecular structures by adding or changing substituents at various positions on the banned molecules. As a result, no substance similar to those forming a prohibited class may be used nowadays, even if it has not been specifically listed. Therefore, reliable, fast and accessible systems capable of modeling and then identifying similarities at molecular level, are highly needed for epidemiological, clinical, and forensic purposes. In order to obtain the expert systems, we have preprocessed a concatenated spectral database, representing the GC-FTIR (gas chromatography-Fourier transform infrared spectrometry) and GC-MS (gas chromatography-mass spectrometry) spectra of 103 forensic compounds. The database was used as input for a Principal Component Analysis (PCA). The scores of the forensic compounds on the main principal components (PCs) were then used as inputs for the ANN systems. We have built eight PC-ANN systems (principal component analysis coupled with artificial neural network) with a different number of input variables: 15 PCs, 16 PCs, 17 PCs, 18 PCs, 19 PCs, 20 PCs, 21 PCs and 22 PCs. The best expert system was found to be the ANN network built with 18 PCs, which accounts for an explained variance of 77%. This expert system has the best sensitivity (a rate of classification C = 100% and a rate of true positives TP = 100%), as well as a good selectivity (a rate of true negatives TN = 92.77%). A

  2. Principal Component Analysis Coupled with Artificial Neural Networks—A Combined Technique Classifying Small Molecular Structures Using a Concatenated Spectral Database

    Directory of Open Access Journals (Sweden)

    Mihail Lucian Birsa

    2011-10-01

    Full Text Available In this paper we present several expert systems that predict the class identity of the modeled compounds, based on a preprocessed spectral database. The expert systems were built using Artificial Neural Networks (ANN and are designed to predict if an unknown compound has the toxicological activity of amphetamines (stimulant and hallucinogen, or whether it is a nonamphetamine. In attempts to circumvent the laws controlling drugs of abuse, new chemical structures are very frequently introduced on the black market. They are obtained by slightly modifying the controlled molecular structures by adding or changing substituents at various positions on the banned molecules. As a result, no substance similar to those forming a prohibited class may be used nowadays, even if it has not been specifically listed. Therefore, reliable, fast and accessible systems capable of modeling and then identifying similarities at molecular level, are highly needed for epidemiological, clinical, and forensic purposes. In order to obtain the expert systems, we have preprocessed a concatenated spectral database, representing the GC-FTIR (gas chromatography-Fourier transform infrared spectrometry and GC-MS (gas chromatography-mass spectrometry spectra of 103 forensic compounds. The database was used as input for a Principal Component Analysis (PCA. The scores of the forensic compounds on the main principal components (PCs were then used as inputs for the ANN systems. We have built eight PC-ANN systems (principal component analysis coupled with artificial neural network with a different number of input variables: 15 PCs, 16 PCs, 17 PCs, 18 PCs, 19 PCs, 20 PCs, 21 PCs and 22 PCs. The best expert system was found to be the ANN network built with 18 PCs, which accounts for an explained variance of 77%. This expert system has the best sensitivity (a rate of classification C = 100% and a rate of true positives TP = 100%, as well as a good selectivity (a rate of true negatives TN

  3. Determination of lead at nanogram level in water samples by resonance light scattering technique using tetrabutyl ammonium bromide as a molecular probe

    Directory of Open Access Journals (Sweden)

    Yanru Yun

    2012-12-01

    Full Text Available A novel method of chemistry applicable to the determination of trace lead in water samples based on the resonance light scattering (RLS technique has been developed. In dilute phosphoric acid medium, in the presence of a large excess of I-, Pb(II can form [PbI4]2-, which further reacts with tetrabutyl ammonium bromide (TBAB to form an ion-association compound. This results in significant enhancement of RLS intensity and the appearance of the corresponding RLS spectral characteristics. The maximum scattering peak of the system exists at 402 nm. Under optimum conditions, there is a linear relationship between the relative intensity of RLS and concentration of Pb(II in the range of 0.04–1.8 μg/mL for the system with a low detection limit of 0.74 ng/mL for Pb(II. Based on this fact, a simple, rapid, and sensitive method has been developed for the determination of Pb(II at nanogram level by RLS technique using a common spectrofluorimeter. This analytical system was successfully applied to determining trace amounts of Pb(II in water samples that agree well with the results by atomic absorbance spectrometry (AAS.DOI: http://dx.doi.org/10.4314/bcse.v26i1.1

  4. Selective Adsorption of Tetrahydropalmatine by a Molecularly ...

    African Journals Online (AJOL)

    NICO

    - ity of the MIP. KEYWORDS. Molecularly imprinted polymer, tetrahydropalmatine, selective adsorption, microcalorimetry, modified rosin. 1. Introduction. Molecular imprinting is a technique for preparing molecular imprinted polymers (MIP) that ...

  5. Evaluación de dos técnicas de subtipificación molecular para el estudio de Pasteurella multocida Evaluation of two techniques of molecular subtyping to study Pasteurella multocida

    Directory of Open Access Journals (Sweden)

    G. A. Leotta

    2006-12-01

    Full Text Available Se determinó la tipibilidad, la reproducibilidad y el poder discriminatorio de ERIC-PCR y ApaI-PFGE para establecer la relación genética de cepas de Pasteurella multocida. Se estudiaron 49 cepas de diferente origen, subespecie, biotipo, grupo capsular, serotipo somático y perfil de resistencia antimicrobiana. Por ERIC-PCR se establecieron 31 patrones, los que presentaron entre 10 y 14 bandas en un rango comprendido entre 0,2 y 1,2 kb. Por ApaI-PFGE se detectaron 37 patrones de restricción, los cuales presentaron entre 7 y 15 bandas bien definidas de 34 a 450 kb. La tipibilidad de ERIC-PCR fue del 100% (T=1 y la de ApaI-PFGE del 94% (T=0,94. La reproducibilidad de ambas técnicas fue del 100% (R=1; sin embargo, el poder discriminatorio de ERIC-PCR fue 93% (D=0,93 y el de ApaI-PFGE 98% (D=0,98. Mediante ambas técnicas fue posible agrupar las cepas con relación epidemiológica y diferenciar claramente las cepas no relacionadas. Se demostró el valor de ERIC-PCR y ApaI-PFGE para complementar estudios epidemiológicos, principalmente si las cepas en estudio son analizadas por ambas técnicas.Typeability, reproducibility, and discriminatory power of ERIC-PCR and ApaI-PFGE to establish the genetic relation of P. multocida strains were determined. Forty-nine strains of different source, biotype, capsular group, somatic serotype, and resistance to antimicrobials were studied. By ERIC-PCR, 31 patterns were defined with 10 to 14 bands in a rank of 0.2 and 1.2 kb. By ApaI-PFGE, 37 restriction patterns were established with 7 to 15 bands of 34 to 450 kb. Typeability was 100% (T=1 for ERIC-PCR, and 94% (T=0.94 for ApaI-PFGE. Reproducibility of both techniques was 100% (R=1. Discriminatory power was 93% (D=0.93 for ERIC-PCR, and 98% (D=0.98 for ApaI-PFGE. By using both techniques, epidemiologically related strains were grouped, and unrelated strains were clearly differentiated. The value of ERIC-PCR and ApaI-PFGE as complements to epidemiologic studies

  6. Review of Papillostrongylus Johnston & Mawson, 1939 (Nematoda: Strongyloidea) from wallabies and kangaroos (Marsupialia: Macropodidae) using morphological and molecular techniques, with the description of P. barbatus n. sp.

    Science.gov (United States)

    Chilton, N B; Huby-Chilton, F; Gasser, R B; Beveridge, I

    2002-02-01

    The strongyloid nematode genus Papillostrongylus Johnston & Mawson, 1939, from kangaroos and wallabies, is reviewed using morphological and molecular methods. P. labiatus Johnston & Mawson, 1939 is re-described from material from the type-host, the black-striped wallaby Macropus dorsalis, from eastern Queensland, Australia, in which it is a relatively common parasite. Additional records from M. parryi and Thylogale thetis are confirmed and considered to represent examples of host-switching. A geographically disjunct population of the nematode species occurs in M. bernardus and Petrogale brachyotis in Arnhem Land, Northern Territory, but assessment of its status requires additional material. Nematodes from M. rufus, M. giganteus, M. fuliginosus and M. robustus from inland regions of Australia, formerly attributed to P. labiatus, are here assigned to a new species, P. barbatus, distinguished by the presence of an external leaf-crown, larger size, by greater spicule length in the male and by a sinuous vagina in the female. Additional hosts of P. barbatus n. sp. are Petrogale assimilis and Pet. lateralis purpureicollis. Sequence analyses of the second internal transcribed spacer of ribosomal DNA (ITS-2) also showed that P. barbatus n. sp. differed at 40 (16.7%) of the 240 alignment positions when compared with P. labiatus. Most of these interspecific sequence differences occurred in loops or bulges of the predicted precursor rRNA secondary structure, or represented partial or total compenstory base pair changes in stems.

  7. Analysis of spin-Hamiltonian and molecular orbital coefficients of Cu2+ doped C8H11KO8 single crystal through EPR technique

    Science.gov (United States)

    Juliet sheela, K.; Krishnan, S. Radha; Shanmugam, V. M.; Subramanian, P.

    2018-04-01

    Electron paramagnetic resonance (EPR) studies have been investigated at X-band microwave frequency on Cu2+ ion incorporated into the single crystal of potassium succinate-succinic acid (KSSA) at room temperature. The angular variation of the EPR spectra has shown two magnetically in-equivalent Cu2+ sites in the KSSA single crystal system. The spin Hamiltonian parameters g and A are determined which reveals that the site I and site II occupied in rhombic and axial local field symmetry around the impurity ion. Among the two paramagnetic impurity ions, sites one occupies at substituitional position in the place of monovalent cation (K+) in the crystal whereas the other enters in its lattice interstitially by the correlation of EPR and crystal structure data. From the calculated principle values gxx, gyy, gzz and Axx, Ayy, Azz of both the sites, the admixture coefficients and molecular orbital coefficients were evaluated which gives the information of ground state wave function and types of bonding of impurity ions with the ligands.

  8. Analysis of the Interaction of Dp44mT with Human Serum Albumin and Calf Thymus DNA Using Molecular Docking and Spectroscopic Techniques

    Directory of Open Access Journals (Sweden)

    Zhongjie Xu

    2016-06-01

    Full Text Available Di-2-pyridylketone-4,4,-dimethyl-3-thiosemicarbazone (Dp44mT exhibits significant antitumor activity. However, the mechanism of its pharmacological interaction with human serum albumin (HSA and DNA remains poorly understood. Here, we aimed to elucidate the interactions of Dp44mT with HSA and DNA using MTT assays, spectroscopic methods, and molecular docking analysis. Our results indicated that addition of HSA at a ratio of 1:1 did not alter the cytotoxicity of Dp44mT, but did affect the cytotoxicity of the Dp44mT-Cu complex. Data from fluorescence quenching and UV-VIS absorbance measurements demonstrated that Dp44mT could bind to HSA with a moderate affinity (Ka = approximately 104 M−1. CD spectra revealed that Dp44mT could slightly disrupt the secondary structure of HSA. Dp44mT could also interact with Ct-DNA, but had a moderate binding constant (KEB = approximately 104 M−1. Docking studies indicated that the IB site of HSA, but not the IIA and IIIA sites, could be favorable for Dp44mT and that binding of Dp44mT to HSA involved hydrogen bonds and hydrophobic force, consistent with thermodynamic results from spectral investigations. Thus, the moderate binding affinity of Dp44mT with HSA and DNA partially contributed to its antitumor activity and may be preferable in drug design approaches.

  9. Molecular basis of interactions between mitochondrial proteins and hydroxyapatite in the presence of Triton X-100, as revealed by proteomic and recombinant techniques.

    Science.gov (United States)

    Yamamoto, Takenori; Tamaki, Haruna; Katsuda, Chie; Nakatani, Kiwami; Terauchi, Satsuki; Terada, Hiroshi; Shinohara, Yasuo

    2013-08-02

    Hydroxyapatite chromatography is a very important step in the purification of voltage-dependent anion channels (VDACs) and several members of solute carrier family 25 (Slc25) from isolated mitochondria. In the presence of Triton X-100, VDACs and Slc25 members present a peculiar property, i.e., a lack of interaction with hydroxyapatite, resulting in their presence in the flow-through fraction of hydroxyapatite chromatography. This property has allowed selective isolation of VDACs and Slc25 members from a mixture of total mitochondrial proteins. However, the reason why only these few proteins are selectively obtained in the presence of Triton X-100 from the flow-though fraction of hydroxyapatite chromatography has not yet been adequately understood. In this study, when we examined the protein species in the flow-through fractions by proteomic analysis, VDAC isoforms, Slc25 members, and some other membrane proteins were identified. All the mitochondrial proteins had in common high hydrophobicity over their entire protein sequences. When the proteins were fused to soluble proteins, the fused proteins showed affinity for hydroxyapatite even in the presence of Triton X-100. Based on these results, we discussed the molecular basis of the interactions between proteins and hydroxyapatite in the presence of Triton X-100. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Molecular identification of peste des petits ruminants virus in wild goat and domestic small ruminants by real-time -PCR technique in Erbil-Iraq

    Directory of Open Access Journals (Sweden)

    E.P. Candlan

    2017-06-01

    Full Text Available In July 2010 outbreak was occurred in wild goat in Barzan, Sherwin mizzen and Mergasur in Kurdistan Region- Iraq. There were over 2700 deaths (both young and adult during the period of July 2010 to October 2011. Based on the clinical signs and post-mortem findings, the involvement of peste des petits ruminants virus (PPRV was suspected. This was confirmed by Real Time PCR technique using TaqMan®probes for the detection of Peste des petits ruminants. The results of Real-Time PCR for the 9 sample taken from 9 Wild goat there are 6 sample positive and 3 sample negative and 76 sample from domestic ruminants (sheep and goat 63 samples was negative for PPR. This result confirms the diagnosis domestic ruminants in the region are routinely vaccinated with an attenuated vaccine based on the ‘Nigeria/75/1’ strain of PPRV.

  11. Analysis of the condition of the SNAP 7-E acoustic beacon installation after 64 months at 2,650 fathoms. Final report Nov 1970--May 1971

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, J.F.

    1972-02-01

    An isotopic generator powered acoustic beacon installation was recovered after 64 months of exposure to the seawater and bottom sediments at 2,650 fathoms of depth in the Atlantic Ocean south of Bermuda. An analysis of the deterioration of the components of the installation showed that the basic steel support structure and the isotopic generator housing suffered only minimal attack. The lifetimes of these elements are projected to exceed ten years at this site. Stainless steel components of the installation were severely corroded and the use of stainless steel is not recommended. The bottom environment in this location was found to be a typical and similar installations at other sites would have significantly shorter lifetimes.

  12. Molecular Typing and Differentiation

    Science.gov (United States)

    In this chapter, general background and bench protocols are provided for a number of molecular typing techniques in common use today. Methods for the molecular typing and differentiation of microorganisms began to be widely adopted following the development of the polymerase chai...

  13. Sampling 4-chlorophenol in water by DGT technique with molecularly imprinted polymer as binding agent and nylon membrane as diffusive layer.

    Science.gov (United States)

    Dong, Jia; Fan, Hongtao; Sui, Dianpeng; Li, Liangchen; Sun, Ting

    2014-04-25

    For the first time, a diffusive gradients in thin films (DGT) device using molecularly imprinted polymer (MIP) as the binding agent and nylon membrane (NM) as the diffusive layer (NM-MIP-DGT) has been developed for sampling 4-chlorophenol (4-CP) in water. The MIP was prepared by precipitation polymerization with methacrylic acid as monomer and ethyleneglycoldimethacrylate as cross-linker. The diffusion coefficient of 4-CP through NM was obtained to be 0.788±0.040 μ cm(2) s(-1) by diffusion cell method. The ratio was 1.01±0.05 (mean±standard deviation) for the concentration of 4-CP sampled by NM-MIP-DGT and analyzed by HPLC method to the total concentration of 4-CP in the synthetic solution where free 4-CP species dominated. The results showed that NM-MIP-DGT could sample 4-CP in synthetic solution accurately. The performance of NM-MIP-DGT for sampling 4-CP was independent of pH in the range of 3-7 and ionic strength in the range of 0.0001-0.1 mol L(-1) NaCl solution. The concentration of free form of 4-CP sampled by NM-MIP-DGT decreased with the increasing concentration of dissolved organic carbon in different water samples due to the electrostatic interaction of natural organic compounds with 4-CP. 1.8 mg L(-1) of the free form of 4-CP was determined by HPLC which was sampled by NM-MIP-DGT in an intermediate untreated industrial effluent. The NM-MIP-DGT can be a potential passive tool for sampling the free form of 4-CP in water. Copyright © 2014. Published by Elsevier B.V.

  14. A Novel Algorithm for Determining the Contextual Characteristics of Movement Behaviors by Combining Accelerometer Features and Wireless Beacons: Development and Implementation.

    Science.gov (United States)

    Magistro, Daniele; Sessa, Salvatore; Kingsnorth, Andrew P; Loveday, Adam; Simeone, Alessandro; Zecca, Massimiliano; Esliger, Dale W

    2018-04-20

    Unfortunately, global efforts to promote "how much" physical activity people should be undertaking have been largely unsuccessful. Given the difficulty of achieving a sustained lifestyle behavior change, many scientists are reexamining their approaches. One such approach is to focus on understanding the context of the lifestyle behavior (ie, where, when, and with whom) with a view to identifying promising intervention targets. The aim of this study was to develop and implement an innovative algorithm to determine "where" physical activity occurs using proximity sensors coupled with a widely used physical activity monitor. A total of 19 Bluetooth beacons were placed in fixed locations within a multilevel, mixed-use building. In addition, 4 receiver-mode sensors were fitted to the wrists of a roving technician who moved throughout the building. The experiment was divided into 4 trials with different walking speeds and dwelling times. The data were analyzed using an original and innovative algorithm based on graph generation and Bayesian filters. Linear regression models revealed significant correlations between beacon-derived location and ground-truth tracking time, with intraclass correlations suggesting a high goodness of fit (R 2 =.9780). The algorithm reliably predicted indoor location, and the robustness of the algorithm improved with a longer dwelling time (>100 s; error location of an individual within an indoor environment. This novel implementation of "context sensing" will facilitate a wealth of new research questions on promoting healthy behavior change, the optimization of patient care, and efficient health care planning (eg, patient-clinician flow, patient-clinician interaction). ©Daniele Magistro, Salvatore Sessa, Andrew P Kingsnorth, Adam Loveday, Alessandro Simeone, Massimiliano Zecca, Dale W Esliger. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 20.04.2018.

  15. Molecular Beacon Enables Combination of Highly Processive and Highly Sensitive Rolling Circle Amplification Readouts for Detection of DNA-Modifying Enzymes

    DEFF Research Database (Denmark)

    Kristoffersen, Emil Laust; Gonzales, Maria; Stougaard, Magnus

    2015-01-01

    Here we present an optimized readout format for detection of the circularized products from a DNA-based sensor for measurement of DNA-modifying enzymes including DNA Topoisomerase I. The basic design of the DNA-sensor relies on the use of a substrate that can be circularized by the activity of DN...

  16. Near-Infrared Fluorescence Imaging Guided Therapy: Molecular Beacon-Based Photosensitizers Triggered by Breast Cancer-Specific mRNA

    Science.gov (United States)

    2007-05-01

    C.; Stephens, P.; Edkins, S.; Clegg, S.; Teague, J.; Woffendin, H.; Garnett, M. J.; Bottomley, W.; Davis, N.; Dicks, E.; Ewing, R.; Floyd , Y...Weissleder, R. Radiology, 1999, 213, 866-70. [98] Chen, J.; Tung, C. H.; Allport , J. R.; Chen, S.; Weissleder, R.; Huang, P. L. Circulation, 2005, 111

  17. Combining molecular and bioprocess techniques to produce poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) with controlled monomer composition by Burkholderia sacchari.

    Science.gov (United States)

    Mendonça, Thatiane T; Tavares, Rafaela R; Cespedes, Lucas G; Sánchez-Rodriguez, Ruben J; Schripsema, Jan; Taciro, Marilda K; Gomez, José G C; Silva, Luiziana F

    2017-05-01

    Biopolymers as polyhydroxyalkanoates (PHA) composed by different co-monomers 3-hydroxybutyrate and 3-hydroxyhexanoate [P(3HB-co-3HHx)] has attracted interest since its properties are similar to low density polyethylene. Burkholderia sacchari produces this copolymer with a very low 3HHx molar fraction, about 2 mol%. B. sacchari mutant (unable to produce polymer) was engineered to host PHA biosynthesis genes (phaPCJ) from Aeromonas sp. In addition, a two-step bioprocess to increase biopolymer production was developed. The combination of these techniques resulted in the production of P(3HB-co-3HHx) with 3HHx content up to 20 mol%. The PHA content was about 78% of dry biomass, resulting in PHA volumetric productivities around 0.45gl -1 h -1 . The P(3HB-co-3HHx) containing 20 mol% of 3HHx presented an elongation at brake of 945%, higher than reported before for this PHA composition. Here we have described an approach to increase 3HHx content into the copolymer, allowing the precise control of the 3HHx molar fractions. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Assessment of the sensitivity and specificity of serological (IFAT) and molecular (direct-PCR) techniques for diagnosis of leishmaniasis in lagomorphs using a Bayesian approach.

    Science.gov (United States)

    de la Cruz, María Luisa; Pérez, Andres; Domínguez, Mercedes; Moreno, Inmaculada; García, Nerea; Martínez, Irene; Navarro, Alejandro; Domínguez, Lucas; Álvarez, Julio

    2016-08-01

    Leishmaniasis, caused by Leishmania infantum , is a vector-borne zoonotic disease that is endemic to the Mediterranean basin. The potential of rabbits and hares to serve as competent reservoirs for the disease has recently been demonstrated, although assessment of the importance of their role on disease dynamics is hampered by the absence of quantitative knowledge on the accuracy of diagnostic techniques in these species. A Bayesian latent-class model was used here to estimate the sensitivity and specificity of the Immuno-fluorescence antibody test (IFAT) in serum and a Leishmania -nested PCR (Ln-PCR) in skin for samples collected from 217 rabbits and 70 hares from two different populations in the region of Madrid, Spain. A two-population model, assuming conditional independence between test results and incorporating prior information on the performance of the tests in other animal species obtained from the literature, was used. Two alternative cut-off values were assumed for the interpretation of the IFAT results: 1/50 for conservative and 1/25 for sensitive interpretation. Results suggest that sensitivity and specificity of the IFAT were around 70-80%, whereas the Ln-PCR was highly specific (96%) but had a limited sensitivity (28.9% applying the conservative interpretation and 21.3% with the sensitive one). Prevalence was higher in the rabbit population (50.5% and 72.6%, for the conservative and sensitive interpretation, respectively) than in hares (6.7% and 13.2%). Our results demonstrate that the IFAT may be a useful screening tool for diagnosis of leishmaniasis in rabbits and hares. These results will help to design and implement surveillance programmes in wild species, with the ultimate objective of early detecting and preventing incursions of the disease into domestic and human populations.

  19. The speciation and subtyping of campylobacter isolates from sewage plants and waste water from a connected poultry abattoir using molecular techniques.

    Science.gov (United States)

    Koenraad, P. M.; Ayling, R.; Hazeleger, W. C.; Rombouts, F. M.; Newell, D. G.

    1995-01-01

    In this study the distribution of phenotypes of campylobacter strains in sewage and surface waters was investigated by subtyping and by speciation of isolates from various aquatic environments. These environments included two municipal sewage plants (SPA and SPB) and waste water from a poultry abattoir (WWA). Both the sewage plants SPA and SPB collected domestic and industrial waste, and SPA received drain water from WWA. SPB received no waste water from any meat-processing plant. The isolates were speciated by PCR and subtyped by PCR/RFLP based on the flagellin PCR products. From all three reservoirs, no Campylobacter lari was isolated, and approximately 80% of the isolates could be identified as C. jejuni and the rest belonged to the C. coli species. The PCR/RFLP typing technique has a high discrimination level and was reproducible between two separate laboratories. The 182 isolates tested yielded 22 distinct Dde I profiles. The results indicate that strains with profiles found in poultry are also detectable in waste water presumed to be solely from domestic and human sources. In addition some strains were unique to the known poultry-related sources, suggesting that avian-specific strains, non-pathogenic to man, may exist in the environment. In contrast some strains were unique to human waste indicating the potential importance of non-poultry sources of infection. No seasonality was observed in the profile distribution. So, at least in the Netherlands, it is unlikely that infections caused by contaminated surface waters contribute to the seasonality of human campylobacteriosis. Images Fig. 1 PMID:8557080

  20. Molecular characterization of the rDNA-ITS sequence and a PCR diagnostic technique for Pileolaria terebinthi, the cause of pistachio rust

    Directory of Open Access Journals (Sweden)

    Hossein ALAEI

    2013-01-01

    Full Text Available Eleven samples of the most important pistachio rust (caused by Pileolaria terebinthi (DC. Cast.,, which causes disease on Beneh (Pistacia atlantica Desf. subsp. mutica (Fisch. & Mey. Rech. F and Kasoor (Pistacia khinjuk Stocks., were collected from herbarium specimens and pistachio fields at the Pistachio Research Institute in Rafsanjan, Iran. The complete sequences of ribosomal DNA internal transcribed spacers ITS1 and ITS2 (rDNA ITS from the samples were determined and analysed. In general, very little rDNA ITS sequence variation was observed between rDNA ITS sequences of P. terebinthi samples. The length of the PCR fragments was 621 bp (for ITS1F-ITS4 and 1177 bp (for ITS1F-rust1, and consisted of 67 bp at the 3 ́ end of 18S rDNA, 93 bp of ITS1 region, 154 bp of 5.8S rDNA, 246 bp of the ITS2 region, 57 bp (for ITS1F-ITS4 and 613 bp (for ITS1F-rust1 at the 5 ́ end of the 28S rDNA. Restriction fragment length polymorphisms (RFLPs of the rDNA-ITS region were used to identify Pileolaria terebinthi. Three strong bands of 105, 134 and 381 bp and five bands of 105, 134, 200, 301 and 437 bp are observed for the fragment of “ITS1F-ITS4” and “ITS1F-rust1”, respectively. A PCR-RFLP diagnostic technique provided effective identification of the species by a unique pattern with the specific restriction enzyme XapI (ApoI.

  1. Status of soil-transmitted helminth infections in schoolchildren in Laguna Province, the Philippines: Determined by parasitological and molecular diagnostic techniques.

    Science.gov (United States)

    Mationg, Mary Lorraine S; Gordon, Catherine A; Tallo, Veronica L; Olveda, Remigio M; Alday, Portia P; Reñosa, Mark Donald C; Bieri, Franziska A; Williams, Gail M; Clements, Archie C A; Steinmann, Peter; Halton, Kate; Li, Yuesheng; McManus, Donald P; Gray, Darren J

    2017-11-01

    Soil-transmitted helminths (STH) are the most common parasitic infections in impoverished communities, particularly among children. Current STH control is through school-based mass drug administration (MDA), which in the Philippines is done twice annually. As expected, MDA has decreased the intensity and prevalence of STH over time. As a result, the common Kato Katz (KK) thick smear method of detecting STH is less effective because it lacks sensitivity in low intensity infections, making it difficult to measure the impact of deworming programs. A cross-sectional study was carried out over a four-week period from October 27, 2014 until November 20, 2014 in Laguna province, the Philippines. Stool samples were collected from 263 schoolchildren, to determine the prevalence of STH and compare diagnostic accuracy of multiplex quantitative polymerase chain reaction (qPCR) with the KK. A large discrepancy in the prevalence between the two techniques was noted for the detection of at least one type of STH infection (33.8% by KK vs. 78.3% by qPCR), Ascaris lumbricoides (20.5% by KK vs. 60.8% by qPCR) and Trichuris trichiura (23.6% by KK vs. 38.8% by qPCR). Considering the combined results of both methods, the prevalence of at least one type of helminth infection, A. lumbricoides, and T. trichiura were 83.3%, 67.7%, and 53.6%, respectively. Sensitivity of the qPCR for detecting at least one type of STH infection, A. lumbricoides, and T. trichiura were 94.1%, 89.9%, and 72.3% respectively; whereas KK sensitivity was 40.6%, 30.3%, and 44.0%, respectively. The qPCR method also detected infections with Ancylostoma spp. (4.6%), Necator americanus (2.3%), and Strongyloides stercoralis (0.8%) that were missed by KK. qPCR may provide new and important diagnostic information to improve assessment of the effectiveness and impact of integrated control strategies particularly in areas where large-scale STH control has led to low prevalence and/or intensity of infection.

  2. MICROPATTERNING OF GOLD SUBSTRATES BASED ON POLY(PROPYLENE SULFIDE-BL-ETHYLENE GLYCOL), (PPS-PEG) BACKGROUND PASSIVATION AND THE MOLECULAR-ASSEMBLY PATTERNING BY LIFT-OFF (MAPL) TECHNIQUE.

    Science.gov (United States)

    Feller, L; Bearinger, J P; Wu, L; Hubbell, J A; Textor, M; Tosatti, S

    2008-07-01

    Poly(propylene sulfide-bl-ethylene glycol (PPS-PEG) is an amphiphilic block copolymer that spontaneously adsorbs onto gold from solution. This results in the formation of a stable polymeric layer that renders the surface protein resistant when an appropriate architecture is chosen. The established molecular assembly patterning by lift-off (MAPL) technique can convert a prestructured resist film into a pattern of biointeractive chemistry and a noninteractive background. Employing the MAPL technique, we produced a micron-scale PPS-PEG pattern on a gold substrate, and then characterized the patterned structure with Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) and Atomic Force Microscopy (AFM). Subsequent exposure of the PPS-PEG/gold pattern to protein adsorption (full human serum) was monitored in situ; SPR-imaging (i-SPR) shows a selective adsorption of proteins on gold, but not on PPS-PEG areas. Analysis shows a reduction of serum adsorption up to 93% on the PPS-PEG areas as compared to gold, in good agreement with previous analysis of homogenously adsorbed PPS-PEG on gold. MAPL patterning of PPS-PEG block copolymers is straightforward, versatile and reproducible, and may be incorporated into biosensor-based surface analysis methods.

  3. Analysis of the differentially expressed low molecular weight peptides in human serum via an N-terminal isotope labeling technique combining nano-liquid chromatography/matrix-assisted laser desorption/ionization mass spectrometry.

    Science.gov (United States)

    Leng, Jiapeng; Zhu, Dong; Wu, Duojiao; Zhu, Tongyu; Zhao, Ningwei; Guo, Yinlong

    2012-11-15

    Peptidomics analysis of human serum is challenging due to the low abundance of serum peptides and interference from the complex matrix. This study analyzed the differentially expressed (DE) low molecular weight peptides in human serum integrating a DMPITC-based N-terminal isotope labeling technique with nano-liquid chromatography and matrix-assisted laser desorption/ionization mass spectrometry (nano-LC/MALDI-MS). The workflow introduced a [d(6)]-4,6-dimethoxypyrimidine-2-isothiocyanate (DMPITC)-labeled mixture of aliquots from test samples as the internal standard. The spiked [d(0)]-DMPITC-labeled samples were separated by nano-LC then spotted on the MALDI target. Both quantitative and qualitative studies for serum peptides were achieved based on the isotope-labeled peaks. The DMPITC labeling technique combined with nano-LC/MALDI-MS not only minimized the errors in peptide quantitation, but also allowed convenient recognition of the labeled peptides due to the 6 Da mass difference. The data showed that the entire research procedure as well as the subsequent data analysis method were effective, reproducible, and sensitive for the analysis of DE serum peptides. This study successfully established a research model for DE serum peptides using DMPITC-based N-terminal isotope labeling and nano-LC/MALDI-MS. Application of the DMPITC-based N-terminal labeling technique is expected to provide a promising tool for the investigation of peptides in vivo, especially for the analysis of DE peptides under different biological conditions. Copyright © 2012 John Wiley & Sons, Ltd.

  4. Experimental techniques; Techniques experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Roussel-Chomaz, P. [GANIL CNRS/IN2P3, CEA/DSM, 14 - Caen (France)

    2007-07-01

    This lecture presents the experimental techniques, developed in the last 10 or 15 years, in order to perform a new class of experiments with exotic nuclei, where the reactions induced by these nuclei allow to get information on their structure. A brief review of the secondary beams production methods will be given, with some examples of facilities in operation or under project. The important developments performed recently on cryogenic targets will be presented. The different detection systems will be reviewed, both the beam detectors before the targets, and the many kind of detectors necessary to detect all outgoing particles after the reaction: magnetic spectrometer for the heavy fragment, detection systems for the target recoil nucleus, {gamma} detectors. Finally, several typical examples of experiments will be detailed, in order to illustrate the use of each detector either alone, or in coincidence with others. (author)

  5. Probing the interaction of human serum albumin with vitamin B2 (riboflavin) and L-Arginine (L-Arg) using multi-spectroscopic, molecular modeling and zeta potential techniques

    Energy Technology Data Exchange (ETDEWEB)

    Memarpoor-Yazdi, Mina [Department of Biology, Faculty of Sciences, Mashhad Branch, Islamic Azad University, Mashhad (Iran, Islamic Republic of); Mahaki, Hanie, E-mail: hanieh.mahaki@gmail.com [Department of Biology, Faculty of Sciences, Mashhad Branch, Islamic Azad University, Mashhad (Iran, Islamic Republic of)

    2013-04-15

    This study was designed to examine the interaction of Riboflavin (RB) and L-Arginine (L-Arg) with human serum albumin (HSA) using different spectroscopic, zeta potential and molecular modeling techniques under imitated physiological conditions. The resonance light scattering (RLS) method determined the critical aggregation concentration of RB on HSA in the presence and absence of L-Arg which confirmed the zeta potential results. The binding constants (K{sub a}) of HSA–RB were 2.5×10{sup 4} and 9.7×10{sup 3} M{sup −1}, respectively in binary and ternary system at the excitation wavelength of 280 nm, also were 7.5×10{sup 3} and 7.3×10{sup 3}, respectively in binary and ternary system at the excitation wavelength of 295 nm. Fluorescence spectroscopy demonstrated that in the presence of L-Arg, the binding constant of HSA–RB was increased. Static quenching was confirmed to results in the fluorescence quenching and FRET. The binding distances between HSA and RB in two- and three-component systems were estimated by the Forster theory which revealed that nonradiative energy transfer from HSA to RB occurred with a high probability. The effect of RB on the conformation of HSA was analyzed using synchronous fluorescence spectroscopy and circular dichroism (CD) in both systems. Docking studies demonstrated a reduction in the binding affinity between RB and HSA in the presence of L-Arg. -- Highlights: ► We studied the interaction of riboflavin with HSA in presence and absence of L-Arg. ► Molecular modeling and zeta-potential used to describe competitive interaction. ► We compared the binding mechanism of riboflavin (RB) to HSA in both systems. ► We determined critical aggregation concentration of RB on HSA in both systems. ► The binding site of RB on HSA in both systems has been determined.

  6. Probing the interaction of human serum albumin with vitamin B2 (riboflavin) and L-Arginine (L-Arg) using multi-spectroscopic, molecular modeling and zeta potential techniques

    International Nuclear Information System (INIS)

    Memarpoor-Yazdi, Mina; Mahaki, Hanie

    2013-01-01

    This study was designed to examine the interaction of Riboflavin (RB) and L-Arginine (L-Arg) with human serum albumin (HSA) using different spectroscopic, zeta potential and molecular modeling techniques under imitated physiological conditions. The resonance light scattering (RLS) method determined the critical aggregation concentration of RB on HSA in the presence and absence of L-Arg which confirmed the zeta potential results. The binding constants (K a ) of HSA–RB were 2.5×10 4 and 9.7×10 3 M −1 , respectively in binary and ternary system at the excitation wavelength of 280 nm, also were 7.5×10 3 and 7.3×10 3 , respectively in binary and ternary system at the excitation wavelength of 295 nm. Fluorescence spectroscopy demonstrated that in the presence of L-Arg, the binding constant of HSA–RB was increased. Static quenching was confirmed to results in the fluorescence quenching and FRET. The binding distances between HSA and RB in two- and three-component systems were estimated by the Forster theory which revealed that nonradiative energy transfer from HSA to RB occurred with a high probability. The effect of RB on the conformation of HSA was analyzed using synchronous fluorescence spectroscopy and circular dichroism (CD) in both systems. Docking studies demonstrated a reduction in the binding affinity between RB and HSA in the presence of L-Arg. -- Highlights: ► We studied the interaction of riboflavin with HSA in presence and absence of L-Arg. ► Molecular modeling and zeta-potential used to describe competitive interaction. ► We compared the binding mechanism of riboflavin (RB) to HSA in both systems. ► We determined critical aggregation concentration of RB on HSA in both systems. ► The binding site of RB on HSA in both systems has been determined

  7. Molecular diversity techniques for chemical databases

    Directory of Open Access Journals (Sweden)

    Peter Willett

    1996-01-01

    Full Text Available There is much current interest in computer-based methods for selecting structurally diverse subsets of chemical databases, e.g., for inclusion in biological screening programme or for the construction of combinatorial libraries. This paper summarises recent work in Sheffield on dissimilarity-based compound selection, which seeks to identify a maximally-dissimilar subset of the molecules in the database. More realistically, this approach seeks to identify a near maximally dissimilar subset, since the identification of the most dissimilar subset requires the use of a combinatorial algorithm that considers all possible subsets of a given dataset.

  8. Molecular techniques for characterisation of pathogens

    DEFF Research Database (Denmark)

    Kampmann, Marie-Louise

    Pathogens have always had a major interest to humans due to their central role in sickness and death. Influenza A annually kills at least 250,000 humans, and has been the cause of millions of further deaths during pandemic years in the past. Plague (Yersinia pestis) has been the cause of the Black...... Death that was leading to the desertion of whole cities, and as a result was for centuries one of the most feared events in human life. For both of these organisms we generally have situations with only very small amounts of pathogen nucleic acids available, usually because many interesting samples...... capture for the detection of Y. pestis in samples from the Justinian plague (600 AD) as an attempt to detect this pathogen as a cause of death in the victims....

  9. Molecular Technique Utilising Sputum For Detecting Wuchereria ...

    African Journals Online (AJOL)

    Background: Lymphatic filariasis is a tropical parasitic disease which has been identified for elimination by 2020 through mass drugs administration. There is a major problem in its diagnosis and sensitive surveillance methods for monitoring the disease elimination programs need to be sought. Objectives: To establish and ...

  10. Molecular techniques for characterisation of pathogens

    DEFF Research Database (Denmark)

    Kampmann, Marie-Louise

    Pathogens have always had a major interest to humans due to their central role in sickness and death. Influenza A annually kills at least 250,000 humans, and has been the cause of millions of further deaths during pandemic years in the past. Plague (Yersinia pestis) has been the cause of the Black...... capture for the detection of Y. pestis in samples from the Justinian plague (600 AD) as an attempt to detect this pathogen as a cause of death in the victims....

  11. Molecular sensors and molecular logic gates

    International Nuclear Information System (INIS)

    Georgiev, N.; Bojinov, V.

    2013-01-01

    Full text: The rapid grow of nanotechnology field extended the concept of a macroscopic device to the molecular level. Because of this reason the design and synthesis of (supra)-molecular species capable of mimicking the functions of macroscopic devices are currently of great interest. Molecular devices operate via electronic and/or nuclear rearrangements and, like macroscopic devices, need energy to operate and communicate between their elements. The energy needed to make a device work can be supplied as chemical energy, electrical energy, or light. Luminescence is one of the most useful techniques to monitor the operation of molecular-level devices. This fact determinates the synthesis of novel fluorescence compounds as a considerable and inseparable part of nanoscience development. Further miniaturization of semiconductors in electronic field reaches their limit. Therefore the design and construction of molecular systems capable of performing complex logic functions is of great scientific interest now. In semiconductor devices the logic gates work using binary logic, where the signals are encoded as 0 and 1 (low and high current). This process is executable on molecular level by several ways, but the most common are based on the optical properties of the molecule switches encoding the low and high concentrations of the input guest molecules and the output fluorescent intensities with binary 0 and 1 respectively. The first proposal to execute logic operations at the molecular level was made in 1988, but the field developed only five years later when the analogy between molecular switches and logic gates was experimentally demonstrated by de Silva. There are seven basic logic gates: AND, OR, XOR, NOT, NAND, NOR and XNOR and all of them were achieved by molecules, the fluorescence switching as well. key words: fluorescence, molecular sensors, molecular logic gates

  12. Separation techniques: Chromatography

    Science.gov (United States)

    Coskun, Ozlem

    2016-01-01

    Chromatography is an important biophysical technique that enables the separation, identification, and purification of the components of a mixture for qualitative and quantitative analysis. Proteins can be purified based on characteristics such as size and shape, total charge, hydrophobic groups present on the surface, and binding capacity with the stationary phase. Four separation techniques based on molecular characteristics and interaction type use mechanisms of ion exchange, surface adsorption, partition, and size exclusion. Other chromatography techniques are based on the stationary bed, including column, thin layer, and paper chromatography. Column chromatography is one of the most common methods of protein purification. PMID:28058406

  13. A novel enzyme-linked immunosorbent assay for detection of Escherichia coli O157:H7 using immunomagnetic and beacon gold nanoparticles

    Science.gov (United States)

    2014-01-01

    This paper presents a functional nanoparticle-enhanced enzyme-linked immunosorbent assay (FNP-ELISA) for detection of enterohemorrhagic Escherichia coli (EHEC) O157:H7. Immunomagnetic nanoparticles (IMMPs) conjugated with monoclonal anti-O157:H7 antibody were used to capture E. coli O157:H7. Beacon gold nanoparticles (B-GNPs) coated with polyclonal anti-O157:H7 and biotin single-stranded DNA (B-DNA) were then subjective to immunoreaction with E. coli O157:H7, which was followed by streptavidin-horseradish peroxidase (Strep-HRP) conjugated with B-GNPs based on a biotin-avidin system. The solutions containing E. coli O157:H7, IMMPs, B-GNPs, and Strep-HRP were collected for detecting color change. The signal was significantly amplified with detection limits of 68 CFU mL-1 in PBS and 6.8 × 102 to 6.8 × 103 CFU mL-1 in the food samples. The FNP-ELISA method developed in this study was two orders of magnitude more sensitive than immunomagnetic separation ELISA (IMS-ELISA) and four orders of magnitude more sensitive than C-ELISA. The entire detection process of E. coli O157:H7 lasted only 3 h, and thus FNP-ELISA is considered as a time-saving method. PMID:24864164

  14. Effect of a Dual Charge on the DNA-Conjugated Redox Probe on DNA Sensing by Short Hairpin Beacons Tethered to Gold Electrodes.

    Science.gov (United States)

    Kékedy-Nagy, László; Shipovskov, Stepan; Ferapontova, Elena E

    2016-08-16

    Charges of redox species can critically affect both the interfacial state of DNA and electrochemistry of DNA-conjugated redox labels and, as a result, the electroanalytical performance of those systems. Here, we show that the kinetics of electron transfer (ET) between the gold electrode and methylene blue (MB) label conjugated to a double-stranded (ds) DNA tethered to gold strongly depend on the charge of the MB molecule, and that affects the performance of genosensors exploiting MB-labeled hairpin DNA beacons. Positively charged MB binds to dsDNA via electrostatic and intercalative/groove binding, and this binding allows the DNA-mediated electrochemistry of MB intercalated into the duplex and, as a result, a complex mode of the electrochemical signal change upon hairpin hybridization to the target DNA, dominated by the "on-off" signal change mode at nanomolar levels of the analyzed DNA. When MB bears an additional carboxylic group, the negative charge provided by this group prevents intimate interactions between MB and DNA, and then the ET in duplexes is limited by the diffusion of the MB-conjugated dsDNA (the phenomenon first shown in Farjami , E. ; Clima , L. ; Gothelf , K. ; Ferapontova , E. E. Anal. Chem. 2011 , 83 , 1594 ) providing the robust "off-on" nanomolar DNA sensing. Those results can be extended to other intercalating redox probes and are of strategic importance for design and development of electrochemical hybridization sensors exploiting DNA nanoswitchable architectures.

  15. [New microbiological techniques].

    Science.gov (United States)

    Schubert, S; Wieser, A; Bonkat, G

    2017-06-01

    Microbiological diagnostic procedures have changed rapidly in recent years. This is especially true in the field of molecular diagnostics. Classical culture-based techniques are still the gold standard in many areas; however, they are already complemented by automated and also molecular techniques to guarantee faster and better quality results. The most commonly used techniques include real-time polymerase chain reaction (RT-PCR) based systems and nucleic acid hybridization. These procedures are used most powerfully from direct patient samples or in assays to detect the presence of nonculturable or fastidious organisms. Further techniques such as DNA sequencing are not yet used routinely for urological samples and can be considered experimental. However, in conjunction with dropping prices and further technical developments, these techniques promise to be used much more in the near future. Regarding bacterial identification from culture, mass spectrometry (MALDI-TOF MS) has become the technique of choice in recent years especially in Europe. It has tremendously shortened the time to result. This is now going to be extended to antibiotic susceptibility testing. This is of paramount importance in view of ever rising antimicrobial resistance rates. Techniques described in this review offer a faster and better microbiological diagnosis. Such continuous improvements are critical especially in times of cost pressure and rising antimicrobial resistance rates. It is in our interest to provide the best possible care for patients and in this regard a good and effective communication between the laboratory and the clinician is of vital importance.

  16. Molecular beam epitaxy

    CERN Document Server

    Pamplin, Brian R

    1980-01-01

    Molecular Beam Epitaxy introduces the reader to the use of molecular beam epitaxy (MBE) in the generation of III-V and IV-VI compounds and alloys and describes the semiconductor and integrated optics reasons for using the technique. Topics covered include semiconductor superlattices by MBE; design considerations for MBE systems; periodic doping structure in gallium arsenide (GaAs); nonstoichiometry and carrier concentration control in MBE of compound semiconductors; and MBE techniques for IV-VI optoelectronic devices. The use of MBE to fabricate integrated optical devices and to study semicond

  17. Magnetismo Molecular (Molecular Magentism)

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Mario S [Universidade Federal Fluminense, Brasil; Moreira Dos Santos, Antonio F [ORNL

    2010-07-01

    The new synthesis processes in chemistry open a new world of research, new and surprising materials never before found in nature can now be synthesized and, as a wonderful result, observed a series of physical phenomena never before imagined. Among these are many new materials the molecular magnets, the subject of this book and magnetic properties that are often reflections of the quantum behavior of these materials. Aside from the wonderful experience of exploring something new, the theoretical models that describe the behavior these magnetic materials are, in most cases, soluble analytically, which allows us to know in detail the physical mechanisms governing these materials. Still, the academic interest in parallel this subject, these materials have a number of properties that are promising to be used in technological devices, such as in computers quantum magnetic recording, magnetocaloric effect, spintronics and many other devices. This volume will journey through the world of molecular magnets, from the structural description of these materials to state of the art research.

  18. 14th international symposium on molecular beams

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This report discusses research being conducted with molecular beams. The general topic areas are as follows: Clusters I; reaction dynamics; atomic and molecular spectroscopy; clusters II; new techniques; photodissociation dynamics; and surfaces.

  19. 14th international symposium on molecular beams

    Energy Technology Data Exchange (ETDEWEB)

    1992-09-01

    This report discusses research being conducted with molecular beams. The general topic areas are as follows: Clusters I; reaction dynamics; atomic and molecular spectroscopy; clusters II; new techniques; photodissociation & dynamics; and surfaces.

  20. Understanding molecular simulation: from algorithms to applications

    NARCIS (Netherlands)

    Frenkel, D.; Smit, B.

    2002-01-01

    Second and revised edition Understanding Molecular Simulation: From Algorithms to Applications explains the physics behind the "recipes" of molecular simulation for materials science. Computer simulators are continuously confronted with questions concerning the choice of a particular technique

  1. 14th international symposium on molecular beams

    International Nuclear Information System (INIS)

    1992-01-01

    This report discusses research being conducted with molecular beams. The general topic areas are as follows: Clusters I; reaction dynamics; atomic and molecular spectroscopy; clusters II; new techniques; photodissociation ampersand dynamics; and surfaces

  2. Molecular biomethods handbook

    National Research Council Canada - National Science Library

    Walker, John M; Rapley, Ralph

    2008-01-01

    ... the reader to a selection of analytical and preparative techniques that we considered to be frequently used by research workers in the field of molecular biology. Clearly, within the constraints of a single volume we had to be selective in the techniques we described. Since the first edition was published, science has continued to move on apace. For example, the use of microarray technology is now commonplace, nanotechnology has entered the scientific literature, microfluidic technology has be...

  3. Molecular hematology

    National Research Council Canada - National Science Library

    Provan, Drew; Gribben, John

    2010-01-01

    ... The molecular basis of hemophilia, 219 Paul LF Giangrande 4 The genetics of acute myeloid leukemias, 42 Carolyn J Owen & Jude Fitzgibbon 19 The molecular basis of von Willebrand disease, 233 Luciano Baronc...

  4. Aplicación de una técnica de Cromatografía de Exclusión molecular para la purificación de ADN en plantas de Coffea sp. APPLICATION OF A TECHNIQUE OF MOLECULAR EXCLUSION CHROMATOGRAPHY FOR THE PURIFICATION OF DNA FROM Coffea sp. PLANTS

    Directory of Open Access Journals (Sweden)

    Ana María García Cepero

    2006-12-01

    Full Text Available Uno de los mayores inconvenientes en la extracción y purificación de biomoléculas a partir de plantas del género Coffea, es un alto contenido de polifenoles y compuestos tánicos. En el presente artículo se describe una metodología que permite obtener ADN de alta pureza. La extracción del ADN del homogeneizado de tejido foliar en siete genotipos de Coffea sp., se realizó mediante la técnica citada por Chaparro (1993 y su purificación se logró mediante cromatografía de exclusión molecular sobre una fase estacionaria de Sephacryl S-1000. Los resultados muestran que la alta eficiencia de separación de ARN degradado, proteínas, pigmentos y compuestos que absorben entre 220 y 300 nm, permiten obtener un ADN de alta pureza a juzgar por los datos espectrofotométricos y electroforéticos.One of the greatest difficulties in extracting and purifying biomolecules from plants in the genus Coffea is the high polyphenol and tannin contents. In this study a methodology is described that allows obtaining high purity DNA from leaf tissues of seven genotypes of Coffea sp. by means of the technique desribed by Chaparro (1993 and its further purification was achieved by molecular exclusion chromatography on Sephacryl S-1000 (Pharmacia. The results showed that the high separation efficiency of degraded RNA, proteins, pigments, and other compounds that absorb between 220 and 300 nm allowed obtaining high purity DNA as judged by the spectophometric and electroforetic data.

  5. Responses of Cell Renewal Systems to Long-term Low-Level Radiation Exposure: A Feasibility Study Applying Advanced Molecular Biology Techniques on Available Histological and Cytological Material of Exposed Animals and Men

    Energy Technology Data Exchange (ETDEWEB)

    Fliedner Theodor M.; Feinendegen Ludwig E.; Meineke Viktor; Fritz Thomas E.

    2005-02-28

    First results of this feasibility study showed that evaluation of the stored material of the chronically irradiated dogs with modern molecular biological techniques proved to be successful and extremely promising. Therefore an in deep analysis of at least part of the huge amount of remaining material is of outmost interest. The methods applied in this feasibility study were pathological evaluation with different staining methods, protein analysis by means of immunohistochemistry, strand break analysis with the TdT-assay, DNA- and RNA-analysis as well as genomic examination by gene array. Overall more than 50% of the investigated material could be used. In particular the results of an increased stimulation of the immune system within the dogs of the 3mSv group as both compared to the control and higher dose groups gives implications for the in depth study of the cellular events occurring in context with low dose radiation. Based on the findings of this study a further evaluation and statistically analysis of more material can help to identify promising biomarkers for low dose radiation. A systematic evaluation of a correlation of dose rates and strand breaks within the dog tissue might moreover help to explain mechanisms of tolerance to IR. One central problem is that most sequences for dog specific primers are not known yet. The discovery of the dog genome is still under progress. In this study the isolation of RNA within the dog tissue was successful. But up to now there are no gene arrays or gene chips commercially available, tested and adapted for canine tissue. The uncritical use of untested genomic test systems for canine tissue seems to be ineffective at the moment, time consuming and ineffective. Next steps in the investigation of genomic changes after IR within the stored dog tissue should be limited to quantitative RT-PCR of tested primer sequences for the dog. A collaboration with institutions working in the field of the discovery of the dog genome could

  6. Cardiovascular Molecular Imaging

    International Nuclear Information System (INIS)

    Lee, Kyung Han

    2009-01-01

    Molecular imaging strives to visualize processes in living subjects at the molecular level. Monitoring biochemical processes at this level will allow us to directly track biological processes and signaling events that lead to pathophysiological abnormalities, and help make personalized medicine a reality by allowing evaluation of therapeutic efficacies on an individual basis. Although most molecular imaging techniques emerged from the field of oncology, they have now gradually gained acceptance by the cardiovascular community. Hence, the availability of dedicated high-resolution small animal imaging systems and specific targeting imaging probes is now enhancing our understanding of cardiovascular diseases and expediting the development of newer therapies. Examples include imaging approaches to evaluate and track the progress of recent genetic and cellular therapies for treatment of myocardial ischemia. Other areas include in vivo monitoring of such key molecular processes as angiogenesis and apoptosis. Cardiovascular molecular imaging is already an important research tool in preclinical experiments. The challenge that lies ahead is to implement these techniques into the clinics so that they may help fulfill the promise of molecular therapies and personalized medicine, as well as to resolve disappointments and controversies surrounding the field

  7. MiRNA-Related SNPs and Risk of Esophageal Adenocarcinoma and Barrett's Esophagus: Post Genome-Wide Association Analysis in the BEACON Consortium.

    Directory of Open Access Journals (Sweden)

    Matthew F Buas

    Full Text Available Incidence of esophageal adenocarcinoma (EA has increased substantially in recent decades. Multiple risk factors have been identified for EA and its precursor, Barrett's esophagus (BE, such as reflux, European ancestry, male sex, obesity, and tobacco smoking, and several germline genetic variants were recently associated with disease risk. Using data from the Barrett's and Esophageal Adenocarcinoma Consortium (BEACON genome-wide association study (GWAS of 2,515 EA cases, 3,295 BE cases, and 3,207 controls, we examined single nucleotide polymorphisms (SNPs that potentially affect the biogenesis or biological activity of microRNAs (miRNAs, small non-coding RNAs implicated in post-transcriptional gene regulation, and deregulated in many cancers, including EA. Polymorphisms in three classes of genes were examined for association with risk of EA or BE: miRNA biogenesis genes (157 SNPs, 21 genes; miRNA gene loci (234 SNPs, 210 genes; and miRNA-targeted mRNAs (177 SNPs, 158 genes. Nominal associations (P0.50, and we did not find evidence for interactions between variants analyzed and two risk factors for EA/BE (smoking and obesity. This analysis provides the most extensive assessment to date of miRNA-related SNPs in relation to risk of EA and BE. While common genetic variants within components of the miRNA biogenesis core pathway appear unlikely to modulate susceptibility to EA or BE, further studies may be warranted to examine potential associations between unassessed variants in miRNA genes and targets with disease risk.

  8. BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service

    Directory of Open Access Journals (Sweden)

    Han Zou

    2016-02-01

    Full Text Available The location and contextual status (indoor or outdoor is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS for individuals. In addition, optimizations of building management systems (BMS, such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption.

  9. BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service.

    Science.gov (United States)

    Zou, Han; Jiang, Hao; Luo, Yiwen; Zhu, Jianjie; Lu, Xiaoxuan; Xie, Lihua

    2016-02-22

    The location and contextual status (indoor or outdoor) is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS) for individuals. In addition, optimizations of building management systems (BMS), such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO) detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS) easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption.

  10. Biophysics of molecular gastronomy.

    Science.gov (United States)

    Brenner, Michael P; Sörensen, Pia M

    2015-03-26

    Chefs and scientists exploring biophysical processes have given rise to molecular gastronomy. In this Commentary, we describe how a scientific understanding of recipes and techniques facilitates the development of new textures and expands the flavor palette. The new dishes that result engage our senses in unexpected ways. PAPERCLIP. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Molecular epidemiology of ascariasis

    DEFF Research Database (Denmark)

    Betson, Martha; Halstead, Fennella; Nejsum, Peter

      We are using molecular epidemiology techniques to study the population structure of Ascaris obtained from humans and pigs. Worms were obtained from human hosts on Zanzibar and in Uganda, Bangladesh, Guatemala and Nepal and Ascaris from pigs were collected from in Uganda, Tanzania, Denmark...

  12. Dismantling techniques

    International Nuclear Information System (INIS)

    Wiese, E.

    1998-01-01

    Most of the dismantling techniques used in a Decontamination and Dismantlement (D and D) project are taken from conventional demolition practices. Some modifications to the techniques are made to limit exposure to the workers or to lessen the spread of contamination to the work area. When working on a D and D project, it is best to keep the dismantling techniques and tools as simple as possible. The workers will be more efficient and safer using techniques that are familiar to them. Prior experience with the technique or use of mock-ups is the best way to keep workers safe and to keep the project on schedule

  13. Molecular ion photofragment spectroscopy

    International Nuclear Information System (INIS)

    Bustamente, S.W.

    1983-11-01

    A new molecular ion photofragment spectrometer is described which features a supersonic molecular beam ion source and a radio frequency octapole ion trap interaction region. This unique combination allows several techniques to be applied to the problem of detecting a photon absorption event of a molecular ion. In particular, it may be possible to obtain low resolution survey spectra of exotic molecular ions by using a direct vibrational predissociation process, or by using other more indirect detection methods. The use of the spectrometer is demonstrated by measuring the lifetime of the O 2 + ( 4 π/sub u/) metastable state which is found to consist of two main components: the 4 π/sub 5/2/ and 4 π/sub -1/2/ spin components having a long lifetime (approx. 129 ms) and the 4 π/sub 3/2/ and 4 π/sub 1/2/ spin components having a short lifetime (approx. 6 ms)

  14. Teaching Molecular Biology with Microcomputers.

    Science.gov (United States)

    Reiss, Rebecca; Jameson, David

    1984-01-01

    Describes a series of computer programs that use simulation and gaming techniques to present the basic principles of the central dogma of molecular genetics, mutation, and the genetic code. A history of discoveries in molecular biology is presented and the evolution of these computer assisted instructional programs is described. (MBR)

  15. Molecular pharmacognosy.

    Science.gov (United States)

    Huang, LuQi; Xiao, PeiGen; Guo, LanPing; Gao, WenYuan

    2010-06-01

    This article analyzes the background and significance of molecular pharmacognosy, including the molecular identification of medicinal raw materials, phylogenetic evolution of medicinal plants and animals, evaluation and preservation of germplasm resources for medicinal plants and animals, etiology of endangerment and protection of endangered medicinal plants and animals, biosynthesis and bioregulation of active components in medicinal plants, and characteristics and the molecular bases of top-geoherbs.

  16. Acquired Techniques

    DEFF Research Database (Denmark)

    Lunde Nielsen, Espen; Halse, Karianne

    2013-01-01

    Acquired Techniques - a Leap into the Archive, at Aarhus School of Architecture. In collaboration with Karianne Halse, James Martin and Mika K. Friis. Following the footsteps of past travelers this is a journey into tools and techniques of the architectural process. The workshop will focus upon...

  17. [Molecular breast imaging. An update].

    Science.gov (United States)

    Pinker, K; Helbich, T H; Magometschnigg, H; Fueger, B; Baltzer, P

    2014-03-01

    The aim of molecular imaging is to visualize and quantify biological, physiological and pathological processes at cellular and molecular levels. Molecular imaging using various techniques has recently become established in breast imaging. Currently molecular imaging techniques comprise multiparametric magnetic resonance imaging (MRI) using dynamic contrast-enhanced MRI (DCE-MRI), diffusion-weighted imaging (DWI), proton MR spectroscopy ((1)H-MRSI), nuclear imaging by breast-specific gamma imaging (BSGI), positron emission tomography (PET) and positron emission mammography (PEM) and combinations of techniques (e.g. PET-CT and multiparametric PET-MRI). Recently, novel techniques for molecular imaging of breast tumors, such as sodium imaging ((23)Na-MRI), phosphorus spectroscopy ((31)P-MRSI) and hyperpolarized MRI as well as specific radiotracers have been developed and are currently under investigation. It can be expected that molecular imaging of breast tumors will enable a simultaneous assessment of the multiple metabolic and molecular processes involved in cancer development and thus an improved detection, characterization, staging and monitoring of response to treatment will become possible.

  18. Description and analysis of assistance in science teaching reform: The reports of Maine's Beacon Center science facilitators and the teachers they help

    Science.gov (United States)

    Kesselheim, Craig

    This study describes the assistance relationship between teachers engaged in school-based science education reform and the full-time facilitators hired to provide their training and support. The model which supplied these facilitators to Maine's "Beacon Center" schools was unique in combining three important design factors: content expertise, the duration of their time on site, and the intensity of the assistance provided. Participant perceptions regarding the usefulness of facilitators' assistance were studied, as were the reported impacts of facilitators' assistance on science teaching practices. Participants in the study were three science facilitators and fourteen teachers. Interviewing was the primary method of data gathering, although daily logs from facilitators also provided essential information. Seven categories of assistance were indicated by participants. Among these were several which assisted teachers' efforts to deliver innovative practices in classroom science. Other categories included one which added to teachers' capacities and one which promoted and guided overall efforts. The seven categories occurred at all three sites, although there were unique patterns in the frequency with which each kind occurred at a site. Factors were described at each site which appear to have affected the forms of assistance which facilitators provided. Teacher perceptions of what made facilitator assistance useful were grouped into two broad categories. Assistance was most useful when it possessed a feature of immediate application or "implementability." Another perception of teachers' related to professional growth value of assistance, including such areas as confidence and content knowledge. Three impacts of facilitator assistance on teachers' practice were also reported in this study: More time spent on science; shifts in science teaching philosophy or instructional preferences; participation in systems-level changes in science teaching. The implications of this

  19. Molecular dynamics

    NARCIS (Netherlands)

    Bergstra, J.A.; Bethke, I.

    2002-01-01

    Molecular dynamics is a model for the structure and meaning of object based programming systems. In molecular dynamics the memory state of a system is modeled as a fluid consisting of a collection of molecules. Each molecule is a collection of atoms with bindings between them. A computation is

  20. Molecular Modeling

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 5. Molecular Modeling: A Powerful Tool for Drug Design and Molecular Docking. Rama Rao Nadendla. General Article Volume 9 Issue 5 May 2004 pp 51-60. Fulltext. Click here to view fulltext PDF. Permanent link:

  1. Molecular motors

    National Research Council Canada - National Science Library

    Schliwa, M

    2003-01-01

    ... and entitled Primitive Motile Systems in Cell Biology, the field has moved from the phenomenological to the mechanistic and from the largely structural to the primarily molecular. We have come to appreciate that at every level of complexity the cell operates through molecular machines. Some of these machines are single molecules that car...

  2. Self-Assembling Molecular Logic Gates Based on DNA Crossover Tiles.

    Science.gov (United States)

    Campbell, Eleanor A; Peterson, Evan; Kolpashchikov, Dmitry M

    2017-07-05

    DNA-based computational hardware has attracted ever-growing attention due to its potential to be useful in the analysis of complex mixtures of biological markers. Here we report the design of self-assembling logic gates that recognize DNA inputs and assemble into crossover tiles when the output signal is high; the crossover structures disassemble to form separate DNA stands when the output is low. The output signal can be conveniently detected by fluorescence using a molecular beacon probe as a reporter. AND, NOT, and OR logic gates were designed. We demonstrate that the gates can connect to each other to produce other logic functions. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Intensity techniques

    DEFF Research Database (Denmark)

    Jacobsen, Finn

    2008-01-01

    The Handbook of Signal Processing in Acoustics will compile the techniques and applications of signal processing as they are used in the many varied areas of Acoustics. The Handbook will emphasize the interdisciplinary nature of signal processing in acoustics. Each Section of the Handbook...... from different areas, will find the self-contained chapters accessible and will be interested in the similarities and differences between the approaches and techniques used in different areas of acoustics....

  4. Molecular approaches for the detection and identification of bifidobacteria and lactobacilli in the human gastrointestinal tract

    NARCIS (Netherlands)

    Satokari, R.M.; Vaughan, E.E.; Smidt, H.; Saarela, M.; Matto, J.; Vos, de W.M.

    2003-01-01

    In this review an overview of various molecular techniques and their application for the detection and identification of bifidobacteria and lactobacilli in the gastrointestinal (GI) tract is presented. The techniques include molecular typing techniques such as amplified ribosomal DNA restriction

  5. Molecular pathology and thyroid FNA.

    Science.gov (United States)

    Poller, D N; Glaysher, S

    2017-12-01

    This review summarises molecular pathological techniques applicable to thyroid FNA. The molecular pathology of thyroid tumours is now fairly well understood. Molecular methods may be used as a rule-in test for diagnosis of malignancy in thyroid nodules, eg BRAF V600E point mutation, use of a seven-gene mutational panel (BRAF V600E, RAS genes, RET/PTC or PAX8/PPARG rearrangement), or as a comprehensive multigene next-generation sequencing panel, eg ThyroSeq v2. Molecular methods can also be applied as rule-out tests for malignancy in thyroid nodules, eg Afirma or ThyroSeq v2 or as markers of prognosis, eg TERT promoter mutation or other gene mutations including BRAF V600E, TP53 and AKT1, and as tests for newly defined tumour entities such as non-invasive follicular thyroid neoplasm with papillary like nuclei, or as a molecular marker(s) for targeted therapies. This review describes practical examples of molecular techniques as applied to thyroid FNA in routine clinical practice and the value of molecular diagnostics in thyroid FNA. It describes the range of molecular abnormalities identified in thyroid nodules and thyroid cancers with some practical applications of molecular methods to diagnosis and prognosis of thyroid nodules and thyroid cancer. © 2017 John Wiley & Sons Ltd.

  6. Recent advances in ophthalmic molecular imaging

    NARCIS (Netherlands)

    Ramos de Carvalho, J Emanuel; Verbraak, Frank D; Aalders, Maurice C; van Noorden, Cornelis J; Schlingemann, Reinier O

    2014-01-01

    The aim of molecular imaging techniques is the visualization of molecular processes and functional changes in living animals and human patients before morphological changes occur at the cellular and tissue level. Ophthalmic molecular imaging is still in its infancy and has mainly been used in small

  7. Molecular imaging in oncology

    Energy Technology Data Exchange (ETDEWEB)

    Schober, Otmar; Riemann, Burkhard (eds.) [Universitaetsklinikum Muenster (Germany). Klinik fuer Nuklearmedizin

    2013-02-01

    Considers in detail all aspects of molecular imaging in oncology, ranging from basic research to clinical applications in the era of evidence-based medicine. Examines technological issues and probe design. Discusses preclinical studies in detail, with particular attention to multimodality imaging. Presents current clinical use of PET/CT, SPECT/CT, and optical imagingWritten by acknowledged experts. The impact of molecular imaging on diagnostics, therapy, and follow-up in oncology is increasing significantly. The process of molecular imaging includes key biotarget identification, design of specific molecular imaging probes, and their preclinical evaluation, e.g., in vivo using small animal studies. A multitude of such innovative molecular imaging probes have already entered clinical diagnostics in oncology. There is no doubt that in future the emphasis will be on multimodality imaging in which morphological, functional, and molecular imaging techniques are combined in a single clinical investigation that will optimize diagnostic processes. This handbook addresses all aspects of molecular imaging in oncology, ranging from basic research to clinical applications in the era of evidence-based medicine. The first section is devoted to technology and probe design, and examines a variety of PET and SPECT tracers as well as multimodality probes. Preclinical studies are then discussed in detail, with particular attention to multimodality imaging. In the third section, diverse clinical applications are presented, and the book closes by looking at future challenges. This handbook will be of value to all who are interested in the revolution in diagnostic oncology that is being brought about by molecular imaging.

  8. Molecular Descriptors

    Science.gov (United States)

    Consonni, Viviana; Todeschini, Roberto

    In the last decades, several scientific researches have been focused on studying how to encompass and convert - by a theoretical pathway - the information encoded in the molecular structure into one or more numbers used to establish quantitative relationships between structures and properties, biological activities, or other experimental properties. Molecular descriptors are formally mathematical representations of a molecule obtained by a well-specified algorithm applied to a defined molecular representation or a well-specified experimental procedure. They play a fundamental role in chemistry, pharmaceutical sciences, environmental protection policy, toxicology, ecotoxicology, health research, and quality control. Evidence of the interest of the scientific community in the molecular descriptors is provided by the huge number of descriptors proposed up today: more than 5000 descriptors derived from different theories and approaches are defined in the literature and most of them can be calculated by means of dedicated software applications. Molecular descriptors are of outstanding importance in the research fields of quantitative structure-activity relationships (QSARs) and quantitative structure-property relationships (QSPRs), where they are the independent chemical information used to predict the properties of interest. Along with the definition of appropriate molecular descriptors, the molecular structure representation and the mathematical tools for deriving and assessing models are other fundamental components of the QSAR/QSPR approach. The remarkable progress during the last few years in chemometrics and chemoinformatics has led to new strategies for finding mathematical meaningful relationships between the molecular structure and biological activities, physico-chemical, toxicological, and environmental properties of chemicals. Different approaches for deriving molecular descriptors here reviewed and some of the most relevant descriptors are presented in

  9. Molecular geometry

    CERN Document Server

    Rodger, Alison

    1995-01-01

    Molecular Geometry discusses topics relevant to the arrangement of atoms. The book is comprised of seven chapters that tackle several areas of molecular geometry. Chapter 1 reviews the definition and determination of molecular geometry, while Chapter 2 discusses the unified view of stereochemistry and stereochemical changes. Chapter 3 covers the geometry of molecules of second row atoms, and Chapter 4 deals with the main group elements beyond the second row. The book also talks about the complexes of transition metals and f-block elements, and then covers the organometallic compounds and trans

  10. Fundamental studies of molecular multiphoton ionization

    International Nuclear Information System (INIS)

    Miller, J.C.; Compton, R.N.

    1984-04-01

    For several years the authors have performed fundamental studies of molecular multiphoton ionization (MPI). We will present a potpourri of techniques and results chosen to illustrate the interesting complexities of molecular MPI. Techniques used include time-of-flight mass spectroscopy, photoelectron spectroscopy, supersonic expansion cooling of molecular beams, harmonic generation, two-color laser MPI, and polarization spectroscopy. Whenever possible the relevance of these results to resonance ionization spectroscopy schemes will be delineated. 23 references, 10 figures

  11. Comparative Ebulliometry: a Simple, Reliable Technique for Accurate Measurement of the Number Average Molecular Weight of Macromolecules. Preliminary Studies on Heavy Crude Fractions Ébulliométrie comparative : technique simple et fiable pour déterminer précisément la masse molaire moyenne en nombre des macromolécules. Etudes préliminaires sur des fractions lourdes de bruts

    Directory of Open Access Journals (Sweden)

    Behar E.

    2006-12-01

    Full Text Available This article is divided into two parts. In the first part, the authors present a comparison of the major techniques for the measurement of the molecular weight of macromolecules. The bibliographic results are gathered in several tables. In the second part, a comparative ebulliometer for the measurement of the number average molecular weight (Mn of heavy crude oil fractions is described. The high efficiency of the apparatus is demonstrated with a preliminary study of atmospheric distillation residues and resins. The measurement of molecular weights up to 2000 g/mol is possible in less than 4 hours with an uncertainty of about 2%. Cet article comprend deux parties. Dans la première, les auteurs présentent une comparaison entre les principales techniques de détermination de la masse molaire de macromolécules. Les résultats de l'étude bibliographique sont rassemblés dans plusieurs tableaux. La seconde partie décrit un ébulliomètre comparatif conçu pour la mesure de la masse molaire moyenne en nombre (Mn des fractions lourdes des bruts. Une illustration de l'efficacité de cet appareil est indiquée avec l'étude préliminaire de résidus de distillation atmosphérique et de résines. En particulier, la mesure de masses molaires pouvant atteindre 2000 g/mol est possible en moins de 4 heures avec une incertitude expérimentale de l'ordre de 2 %.

  12. Primer on molecular genetics

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-01

    This report is taken from the April 1992 draft of the DOE Human Genome 1991--1992 Program Report, which is expected to be published in May 1992. The primer is intended to be an introduction to basic principles of molecular genetics pertaining to the genome project. The material contained herein is not final and may be incomplete. Techniques of genetic mapping and DNA sequencing are described.

  13. Molecular Electronics

    DEFF Research Database (Denmark)

    Jennum, Karsten Stein

    This thesis includes the synthesis and characterisation of organic compounds designed for molecular electronics. The synthesised organic molecules are mainly based on two motifs, the obigo(phenyleneethynylenes) (OPE)s and tetrathiafulvalene (TTF) as shown below. These two scaffolds (OPE and TTF......) are chemically merged together to form cruciform-like structures that are an essential part of the thesis. The cruciform molecules were subjected to molecular conductance measurements to explore their capability towards single-crystal field-effect transistors (Part 1), molecular wires, and single electron...... transistors (Part 2). The synthetic protocols rely on stepwise Sonogashira coupling reactions. Conductivity studies on various OPE-based molecular wires reveal that mere OPE compounds have a higher electrical resistance compared to the cruciform based wires (up to 9 times higher). The most spectacular result...

  14. Molecular sciences

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    The research in molecular sciences summarized includes photochemistry, radiation chemistry, geophysics, electromechanics, heavy-element oxidizers , heavy element chemistry collisions, atoms, organic solids. A list of publications is included

  15. Modern techniques of surface science

    CERN Document Server

    Woodruff, D Phil

    2016-01-01

    This fully revised, updated and reorganised third edition provides a thorough introduction to the characterisation techniques used in surface science and nanoscience today. Each chapter brings together and compares the different techniques used to address a particular research question, including how to determine the surface composition, surface structure, surface electronic structure, surface microstructure at different length scales (down to sub-molecular), and the molecular character of adsorbates and their adsorption or reaction properties. Readers will easily understand the relative strengths and limitations of the techniques available to them and, ultimately, will be able to select the most suitable techniques for their own particular research purposes. This is an essential resource for researchers and practitioners performing materials analysis, and for senior undergraduate students looking to gain a clear understanding of the underlying principles and applications of the different characterisation tec...

  16. The ANTARES optical beacon system

    NARCIS (Netherlands)

    Ageron, M.; Aguilar, J. A.; Albert, A.; Ameli, F.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardellier-Desages, F.; Aslanides, E.; Aubert, J-J.; Auer, R.; Barbarito, E.; Basa, S.; Battaglieri, M.; Becherini, Y.; Beltramelli, J.; Bertin, V.; Bigi, A.; Billault, M.; Blaes, R.; de Botton, N.; Bradbury, S. M.; Bruijn, R.; Brunner, J.; Burgio, G. F.; Busto, J.; Cafagna, F.; Caillat, L.; Calzas, A.; Capone, A.; Caponetto, L.; Carmona, E.; Carr, J.; Cartwright, S. L.; Castel, D.; Castorina, E.; Cavasinni, V.; Cecchini, S.; Ceres, A.; Charvis, P.; Chauchot, P.; Chiarusi, T.; Circella, M.; Colnard, C.; Compere, C.; Coniglione, R.; Cottini, N.; Coyle, P.; Cuneo, S.; Cussatlegras, A-S.; Damy, G.; van Dantzig, R.; De Bonis, G.; De Marzo, C.; De Vita, R.; Dekeyser, I.; Delagnes, E.; Denans, D.; Deschamps, A.; Destelle, J-J.; Dinkespieler, B.; Distefano, C.; Donzaud, C.; Drogou, J-F.; Druillole, F.; Durand, D.; Ernenwein, J-P.; Escoffier, S.; Falchini, E.; Favard, S.; Fehr, F.; Feinstein, F.; Ferry, S.; Fiorello, C.; Flaminio, V.; Fratini, K.; Fuda, J-L.; Galeotti, S.; Gallone, J-M.; Giacomelli, G.; Girard, N.; Gojak, C.; Goret, Ph.; Graf, K.; Hallewell, G.; Harakeh, M. N.; Hartmann, B.; Heijboer, A.; Heine, E.; Hello, Y.; Hernandez-Rey, J. J.; Hoessl, J.; Hoffman, C.; Hogenbirk, J.; Hubbard, J. R.; Jaquet, M.; de Jong, M.; Jouvenot, F.; Kalantar-Nayestanaki, N.; Kappes, A.; Karg, T.; Katz, U.; Keller, P.; Kok, E.; Kok, H.; Kooijman, P.; Kopper, C.; Korolkova, E. V.; Kouchner, A.; Kretschmer, W.; Kruijer, A.; Kuch, S.; Kudryavstev, V. A.; Lagier, P.; Lahmann, R.; Lamanna, G.; Lamare, P.; Lambard, G.; Languillat, J-C.; Laschinsky, H.; Lavalle, J.; Le Guen, Y.; Le Provost, H.; Van Suu, A. Le; Lefevre, D.; Legou, T.; Lelaizant, G.; Lim, G.; Lo Presti, D.; Löhner, H.; Loucatos, S.; Louis, F.; Lucarelli, F.; Lyashuk, V.; Marcelin, M.; Margiotta, A.; Masullo, R.; Mazeas, F.; Mazure, A.; McMillan, J. E.; Megna, R.; Melissas, M.; Migneco, E.; Milovanovic, A.; Mongelli, M.; Montaruli, T.; Morganti, M.; Moscoso, L.; Musumeci, M.; Naumann-Godo, M.; Naumann, C.; Niess, V.; Noble, T.; Olivetto, C.; Ostasch, R.; Palanque-Delabrouille, N.; Payre, P.; Peek, H.; Perez, A.; Petta, C.; Piattelli, P.; Pillet, R.; Pineau, J-P.; Poinsignon, J.; Popa, V.; Pradier, T.; Racca, C.; Randazzo, N.; van Randwijk, J.; Real, D.; van Rens, B.; Rethore, F.; Rewiersma, P.; Riccobene, G.; Rigaud, V.; Ripani, M.; Roca, V.; Roda, C.; Rolin, J. F.; Rose, H. J.; Rostovtsev, A.; Roux, J.; Ruppi, M.; Russo, G. V.; Rusydi, G.; Salesa, F.; Salomon, K.; Sapienza, P.; Schmitt, F.; Schuller, J-P.; Shanidze, R.; Sokalski, I.; Spona, T.; Spurio, M.; van der Steenhoven, G.; Stolarczyk, T.; Streeb, K.; Sulak, L.; Taiuti, M.; Tamburini, C.; Tao, C.; Terreni, G.; Thompson, L. F.; Urbano, F.; Valdy, P.; Valente, V.; Vallage, B.; Vaudaine, G.; Venekamp, G.; Verlaat, B.; Vernin, P.; de Vries-Uiterweerd, G.; Wijnker, G.; Huberts, P. de Witt; Wobbe, G.; de Wolf, E.; Yao, A-F.; Zaborov, D.; Zaccone, H.; Zornoza, J. D.; Zuniga, J.; van Wijk, R.

    2007-01-01

    ANTARES is a neutrino telescope being deployed in the Mediterranean Sea. It consists of a three-dimensional array of photomultiplier tubes that can detect the Cherenkov light induced by charged particles produced in the interactions of neutrinos with the surrounding medium. High angular resolution

  17. Underwater Acoustic Beacon Location System

    Science.gov (United States)

    2016-12-23

    distance is the predicted detection range R based on consideration of Equations (1) and (2) together with the parameters for SL, NL, DI, DT and alpha ...R nvnv nvnv ia               cossin0 sincos0 0012 (12) [0091] Finally, the positions on the seafloor 500 in the array...numerical values of the beam pattern projected onto the seafloor are divided by the sum of all of the (non- zero ) numerical values projected onto the

  18. Beacons of the Experience Economy

    DEFF Research Database (Denmark)

    Delica, Kristian Nagel

    2014-01-01

    This essay outlines the boundaries among various interests in the library sector; among positions that prioritize libraries as aesthetically appealing junctions of the experience economy versus positions that prioritize the library as a community forum. The main emphasis is placed on developments...... in the Danish library sector with the additional inclusion of international examples....

  19. Preliminary results on application of the multiple-scattering technique to electron--molecule scattering and molecular photoionization: the PI/sub g/ resonance in e-N2 scattering

    International Nuclear Information System (INIS)

    Dehmer, J.L.; Dill, D.

    1974-01-01

    A prototype calculation of the well-known 2.5-eV shape resonance in e-N 2 scattering was performed to test the usefulness of the multiple-scattering method for electronic continuum molecular wavefunctions. The results of this demanding test are very encouraging. (U.S.)

  20. Radionuclide techniques

    International Nuclear Information System (INIS)

    Alazraki, N.

    1988-01-01

    During approximately 25 years of experience with bone scanning, broad expansions in the clinical impact of radionuclide imaging on disorders of bones, joints, and soft tissues have occurred. This increased impact had its groundwork laid by advances in radiopharmaceuticals and instruments that are used for bone imaging. The progression from /sup 85/Sr- to /sup 99m/Tc-labeled phosphate and phosphonate compounds, coupled with the advance from crude rectilinear scanning techniques to whole body scintillation imaging with large crystal cameras and sophisticated electronics, has encourage use of radionuclide techniques in the evaluation of muscoloskeletal diseases. Many clinical studies have documented the high degree of sensitivity of the bone scan compared with that of the radiograph in detecting osseous and articular abnormalities