WorldWideScience

Sample records for replicate gel spots

  1. Matching Two-dimensional Gel Electrophoresis' Spots

    DEFF Research Database (Denmark)

    Dos Anjos, António; AL-Tam, Faroq; Shahbazkia, Hamid Reza

    2012-01-01

    This paper describes an approach for matching Two-Dimensional Electrophoresis (2-DE) gels' spots, involving the use of image registration. The number of false positive matches produced by the proposed approach is small, when compared to academic and commercial state-of-the-art approaches. This ar......This paper describes an approach for matching Two-Dimensional Electrophoresis (2-DE) gels' spots, involving the use of image registration. The number of false positive matches produced by the proposed approach is small, when compared to academic and commercial state-of-the-art approaches...

  2. Liquid Crystal Gel Reduces Age Spots by Promoting Skin Turnover

    Directory of Open Access Journals (Sweden)

    Mina Musashi

    2014-07-01

    Full Text Available Studies have shown that liquid crystals structurally resembling the intercellular lipids in the stratum corneum can beneficially affect the skin when applied topically by stimulating the skin’s natural regenerative functions and accelerating epidermal turnover. In the present study, the effects of applying low concentrations of a liquid crystal gel of our own creation were evaluated using epidermal thickening in mouse skin as an assay for effective stimulation of epidermal turnover. A liquid crystal gel was also applied topically to human facial skin, and analysis was conducted using before-and-after photographs of age spots, measurements of L* values that reflect degree of skin pigmentation, single-layer samples of the stratum corneum obtained via tape-stripping, and measurements of trans-epidermal water loss that reflect the status of the skin’s barrier function. The results suggested that cost-effective creams containing as low as 5% liquid crystal gel might be effective and safely sold as skin care products targeting age spots and other problems relating to uneven skin pigmentation.

  3. Comparative fluorescence two-dimensional gel electrophoresis using a gel strip sandwich assembly for the simultaneous on-gel generation of a reference protein spot grid.

    Science.gov (United States)

    Ackermann, Doreen; Wang, Weiqun; Streipert, Benjamin; Geib, Birgit; Grün, Lothar; König, Simone

    2012-05-01

    The comparison of proteins separated on 2DE is difficult due to gel-to-gel variability. Here, a method named comparative fluorescence gel electrophoresis (CoFGE) is presented, which allows the generation of an artificial protein grid in parallel to the separation of an analytical sample on the same gel. Different fluorescent stains are used to distinguish sample and marker on the gel. The technology combines elements of 1DE and 2DE. Special gel combs with V-shaped wells are placed in a stacking gel above the pI strip. Proteins separated on the pI strip are electrophoresed at the same time as marker proteins (commercially available purified protein of different molecular weight) placed in V-wells. In that way, grids providing approximately 100 nodes as landmarks for the determination of protein spot coordinates are generated. Data analysis is possible with commercial 2DE software capable of warping. The method improves comparability of 2DE protein gels, because they are generated in combination with regular in-gel anchor points formed by protein standards. This was shown here for two comparative experiments with three gels each using Escherichia coli lysate. For a set of 47 well-defined samples spots, the deviation of the coordinates was improved from 7% to less than 1% applying warping using the marker grid. Conclusively, as long as the same protein markers, the same size of pI-strips and the same technology are used, gel matching is reproducibly possible. This is an important advancement for projects involving comparison of 2DE-gels produced over several years and in different laboratories. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Liquid Crystal Gel Reduces Age Spots by Promoting Skin Turnover

    OpenAIRE

    Mina Musashi; Ariella Coler-Reilly; Teruaki Nagasawa; Yoshiki Kubota; Satomi Kato; Yoko Yamaguchi

    2014-01-01

    Studies have shown that liquid crystals structurally resembling the intercellular lipids in the stratum corneum can beneficially affect the skin when applied topically by stimulating the skin’s natural regenerative functions and accelerating epidermal turnover. In the present study, the effects of applying low concentrations of a liquid crystal gel of our own creation were evaluated using epidermal thickening in mouse skin as an assay for effective stimulation of epidermal turnover. A liquid ...

  5. On the quantitative Amido Black B staining of protein spots in agar gel at low local protein concentrations

    NARCIS (Netherlands)

    Jansen, M.T.

    1962-01-01

    Protein spots in agar gel of identical protein content but different in surface area are found to bind different amounts of dye upon staining with Amido Black B. The lower the protein concentration within the agar gel, the more the Amido Black B content of the spot falls short of the value expected

  6. New algorithmic approaches to protein spot detection and pattern matching in two-dimensional electrophoresis gel databases.

    Science.gov (United States)

    Pleissner, K P; Hoffmann, F; Kriegel, K; Wenk, C; Wegner, S; Sahlström, A; Oswald, H; Alt, H; Fleck, E

    1999-01-01

    Protein spot identification in two-dimensional electrophoresis gels can be supported by the comparison of gel images accessible in different World Wide Web two-dimensional electrophoresis (2-DE) gel protein databases. The comparison may be performed either by visual cross-matching between gel images or by automatic recognition of similar protein spot patterns. A prerequisite for the automatic point pattern matching approach is the detection of protein spots yielding the x(s),y(s) coordinates and integrated spot intensities i(s). For this purpose an algorithm is developed based on a combination of hierarchical watershed transformation and feature extraction methods. This approach reduces the strong over-segmentation of spot regions normally produced by watershed transformation. Measures for the ellipticity and curvature are determined as features of spot regions. The resulting spot lists containing x(s),y(s),i(s)-triplets are calculated for a source as well as for a target gel image accessible in 2-DE gel protein databases. After spot detection a matching procedure is applied. Both the matching of a local pattern vs. a full 2-DE gel image and the global matching between full images are discussed. Preset slope and length tolerances of pattern edges serve as matching criteria. The local matching algorithm relies on a data structure derived from the incremental Delaunay triangulation of a point set and a two-step hashing technique. For the incremental construction of triangles the spot intensities are considered in decreasing order. The algorithm needs neither landmarks nor an a priori image alignment. A graphical user interface for spot detection and gel matching is written in the Java programming language for the Internet. The software package called CAROL (http://gelmatching.inf.fu-berlin.de) is realized in a client-server architecture.

  7. Deposition of sol-gel sensor spots by nanoimprint lithography and hemi-wicking

    DEFF Research Database (Denmark)

    Mikkelsen, Morten Bo Lindholm; Marie, Rodolphe; Hansen, Jan H.

    2011-01-01

    We present a method for homogeneous deposition of sol-gel sensor materials, which enable fabrication of sensor spots for optical pH and oxygen measurements inside plastic containers. A periodic pattern of posts is imprinted into a polycarbonate substrate and, using the principle of hemi-wicking, ......We present a method for homogeneous deposition of sol-gel sensor materials, which enable fabrication of sensor spots for optical pH and oxygen measurements inside plastic containers. A periodic pattern of posts is imprinted into a polycarbonate substrate and, using the principle of hemi......-wicking, a deposited droplet spreads, guided by the posts, to automatically fill the imprinted structure, not being sensitive to alignment as long as it is deposited inside the patterned area. Hemi-wicking is an effective method to immobilize a low viscosity liquid material in well-defined spots on a surface, when...... conventional methods such as screen- or stamp-printing do not work. On length scales of the order of the microstructure period, surface tension will govern the shape of the liquid-air interface, and the liquid will climb up the pillars to keep a fixed contact angle with the sidewalls. The surface to volume...

  8. Melon necrotic spot virus Replication Occurs in Association with Altered Mitochondria.

    Science.gov (United States)

    Gómez-Aix, Cristina; García-García, María; Aranda, Miguel A; Sánchez-Pina, María Amelia

    2015-04-01

    Melon necrotic spot virus (MNSV) (genus Carmovirus, family Tombusviridae) is a single-stranded, positive-sense RNA virus that has become an experimental model for the analysis of cell-to-cell virus movement and translation of uncapped viral RNAs, whereas little is known about its replication. Analysis of the cytopathology after MNSV infection showed the specific presence of modified organelles that resemble mitochondria. Immunolocalization of the glycine decarboxylase complex (GDC) P protein in these organelles confirmed their mitochondrial origin. In situ hybridization and immunolocalization experiments showed the specific localization of positive-sense viral RNA, capsid protein (CP), and double-stranded (ds)RNA in these organelles meaning that replication of the virus takes place in association with them. The three-dimensional reconstructions of the altered mitochondria showed the presence of large, interconnected, internal dilations which appeared to be linked to the outside cytoplasmic environment through pores and/or complex structures, and with lipid bodies. Transient expression of MNSV p29 revealed that its specific target is mitochondria. Our data document the extensive reorganization of host mitochondria induced by MNSV, which provides a protected environment to viral replication, and show that the MNSV p29 protein is the primary determinant of this effect in the host.

  9. Sol-gel replicated optics made from single point diamond turned masters exhibit fractal surface roughness

    Energy Technology Data Exchange (ETDEWEB)

    Bernacki, B.E.; Miller, A.C. Jr.; Evans, B.M. III [Oak Ridge National Lab., TN (United States); Moreshead, W.V.; Nogues, J.L.R. [GELTECH, Inc., Alachua, FL (United States)

    1996-05-01

    Deterministic optics manufacturing, notably single point diamond turning (SPDT) has matured such that the current generation of machines is capable of producing refractive and reflective optics for the visible wavelength region that are quite acceptable for many applications. However, spiral tool marks are still produced that result in unwanted diffractive scattering from grating-like features having a spatial frequency determined by the machine feed, tool radius, and other influences such as vibration and material removal effects. Such regular artifacts are the characteristic of deterministic manufacturing methods such as SPDT. The authors present some initial findings suggesting that fractal, or non-deterministic surfaces can be produced by SPDT through sol-gel replication. The key is the large isotropic shrinkage that occurs through monolithic sol-gel replication (a factor of 2.5) that results in all features, including tooling marks, being reduced by that amount. The large shrinkage itself would be a laudable-enough feature of the replication process. However, by an as-yet-not understood manner, the replication process itself seems to alter the roughness character of the replicated surface such that it appears to be fractal when analyzed using contact profilometry and the power spectrum approach.

  10. Horizontal comparative fluorescence two-dimensional gel electrophoresis for improved spot coordinate detection.

    Science.gov (United States)

    Hanneken, Marina; König, Simone

    2014-04-01

    Vertical comparative 2D fluorescence gel electrophoresis (CoFGE) has recently been shown to increase the reproducibility of coordinate assignment for protein spots, in particular in singular experiments, which cannot be investigated using DIGE. The method applies a standardized marker grid formed by a set of purified proteins to the sample proteome in a conglomerate of 1DE, 2DE, and DIGE. Here, improvements are demonstrated by transferring CoFGE to horizontal 2DE. These include the elimination of the protein modification by residual acrylamide monomer unavoidable in vertical CoFGE, reduced buffer volumes, and highly efficient laboratory procedures. Spot patterns are well defined and can be easily analyzed using commercially available warping algorithms. With horizontal CoFGE also a correction for changes in pI was introduced using a third fluorescent dye. Horizontal CoFGE holds high promises in comparative proteomics. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Statistical Analysis of Microarray Data with Replicated Spots: A Case Study with Synechococcus WH8102

    Directory of Open Access Journals (Sweden)

    E. V. Thomas

    2009-01-01

    Full Text Available Until recently microarray experiments often involved relatively few arrays with only a single representation of each gene on each array. A complete genome microarray with multiple spots per gene (spread out spatially across the array was developed in order to compare the gene expression of a marine cyanobacterium and a knockout mutant strain in a defined artificial seawater medium. Statistical methods were developed for analysis in the special situation of this case study where there is gene replication within an array and where relatively few arrays are used, which can be the case with current array technology. Due in part to the replication within an array, it was possible to detect very small changes in the levels of expression between the wild type and mutant strains. One interesting biological outcome of this experiment is the indication of the extent to which the phosphorus regulatory system of this cyanobacterium affects the expression of multiple genes beyond those strictly involved in phosphorus acquisition.

  12. Crayfish hematopoietic tissue cells but not hemocytes are permissive for white spot syndrome virus replication.

    Science.gov (United States)

    Wu, Junjun; Li, Fang; Huang, Jiajun; Xu, Limei; Yang, Feng

    2015-03-01

    Hemocytes are the major immune cells of crustaceans which are believed to be essential for the pathogenesis of white spot syndrome virus (WSSV) infection. Crayfish hemocytes and hematopoietic tissue (HPT) cells have been found to be susceptible to WSSV infection, but the procedure of WSSV infection to both cell types has not yet been carefully investigated. In this study, we analyzed the infection and proliferation of WSSV in crayfish hemocytes as well as HPT cells in detail through transmission electronic microscopy (TEM). The results showed that WSSV could enter both hemocytes and HPT cells through endocytosis, but the production of progeny virus was only achieved in HPT cells. Further investigation demonstrated that although WSSV could transcribe its genes in both cell types, viral genome replication and structural protein expression were unsuccessful in hemocytes, which may be responsible for the failure of progeny production. Therefore, we propose that both hemocytes and HPT cells are susceptible to WSSV infection but only HPT cells are permissive to WSSV replication. These findings will extend our knowledge of the interaction between WSSV and the host immune system.

  13. Hijacking of host calreticulin is required for the white spot syndrome virus replication cycle.

    Science.gov (United States)

    Watthanasurorot, Apiruck; Guo, Enen; Tharntada, Sirinit; Lo, Chu-Fang; Söderhäll, Kenneth; Söderhäll, Irene

    2014-07-01

    We have previously shown that multifunctional calreticulin (CRT), which resides in the endoplasmic reticulum (ER) and is involved in ER-associated protein processing, responds to infection with white spot syndrome virus (WSSV) by increasing mRNA and protein expression and by forming a complex with gC1qR and thereby delaying apoptosis. Here, we show that CRT can directly interact with WSSV structural proteins, including VP15 and VP28, during an early stage of virus infection. The binding of VP28 with CRT does not promote WSSV entry, and CRT-VP15 interaction was detected in the viral genome in virally infected host cells and thus may have an effect on WSSV replication. Moreover, CRT was detected in the viral envelope of purified WSSV virions. CRT was also found to be of high importance for proper oligomerization of the viral structural proteins VP26 and VP28, and when CRT glycosylation was blocked with tunicamycin, a significant decrease in both viral replication and assembly was detected. Together, these findings suggest that CRT confers several advantages to WSSV, from the initial steps of WSSV infection to the assembly of virions. Therefore, CRT is required as a "vital factor" and is hijacked by WSSV for its replication cycle. Importance: White spot syndrome virus (WSSV) is a double-stranded DNA virus and the cause of a serious disease in a wide range of crustaceans that often leads to high mortality rates. We have previously shown that the protein calreticulin (CRT), which resides in the endoplasmic reticulum (ER) of the cell, is important in the host response to the virus. In this report, we show that the virus uses this host protein to enter the cell and to make the host produce new viral structural proteins. Through its interaction with two viral proteins, the virus "hijacks" host calreticulin and uses it for its own needs. These findings provide new insight into the interaction between a large DNA virus and the host protein CRT and may help in understanding

  14. Using a cross-model loadings plot to identify protein spots causing 2-DE gels to become outliers in PCA

    DEFF Research Database (Denmark)

    Kristiansen, Luise Cederkvist; Jacobsen, Susanne; Jessen, Flemming

    2010-01-01

    The multivariate method PCA is an exploratory tool often used to get an overview of multivariate data, such as the quantified spot volumes of digitized 2-DE gels. PCA can reveal hidden structures present in the data, and thus enables identification of potential outliers and clustering. Based on P...

  15. In vitro white spot syndrome virus (WSSV) replication in explants of the heart of freshwater crab, Paratelphusa hydrodomous.

    Science.gov (United States)

    Nathiga Nambi, K S; Abdul Majeed, S; Sundar Raj, N; Taju, G; Madan, N; Vimal, S; Sahul Hameed, A S

    2012-08-01

    Explants from different organs of freshwater crab, Paratelphusa hydrodomous were prepared to establish an in vitro system for replication of white spot syndrome virus (WSSV) of shrimp. Heart explants were maintained for 53 days without any morphological changes in EX-CELL™ 405 medium with and without serum whereas the explants of eye muscle, gill, shell membrane and appendage muscle died within 15 days of culture period. The heart explants on different days of culture were exposed to WSSV for 10 days to study the viral replication. The infection of WSSV in explants of the heart was confirmed by PCR, RT-PCR, Western blot, histology, immunohistochemistry, bioassay and transmission electron microscopy. The WSSV was quantified by real-time PCR and indirect ELISA. The WSSV inoculum prepared from the heart explants of crab caused significant mortality in Penaeus monodon in challenge experiments and the results indicate that the WSSV which replicated in the heart explants of freshwater crab maintains its infectivity as in marine shrimp. The results indicate that the heart explants of P. hydrodomous would be a good alternative to whole animals for production of WSSV.

  16. A gC1qR prevents white spot syndrome virus replication in the freshwater crayfish Pacifastacus leniusculus.

    Science.gov (United States)

    Watthanasurorot, Apiruck; Jiravanichpaisal, Pikul; Söderhäll, Irene; Söderhäll, Kenneth

    2010-10-01

    The gC1qR/p32 protein is a multiple receptor for several proteins and pathogens. We cloned a gC1qR homologue in a crustacean, Pacifastacus leniusculus, and analyzed the expression of P. leniusculus C1qR (PlgC1qR) in various tissues. The gC1qR/p32 transcript was significantly enhanced by white spot syndrome virus (WSSV) infection 6 h after viral infection both in vitro in a hematopoietic tissue cell culture (Hpt) and in vivo compared to appropriate controls. Moreover, PlgC1qR silencing in both the Hpt cell culture and live crayfish enhanced the WSSV replication. In addition, by making a recombinant PlgC1qR protein we could show that if this recombinant protein was injected in a crayfish, Pacifastacus leniusculus, followed by injection of WSSV, this significantly reduced viral replication in vivo. Furthermore, if the recombinant PlgC1qR was incubated with Hpt cells and then WSSV was added, this also reduced viral replication. These experiments clearly demonstrate that recombinant PlgC1qR reduce WSSV replication both in vivo and in vitro. The results from a far-Western overlay and glutathione S-transferase pull-down assays showed that PlgC1qR could bind to VP15, VP26, and VP28. Altogether, these results demonstrate a role for PlgC1qR in antiviral activity against WSSV.

  17. Control of White Spot Lesion Adjacent to Orthodontic Bracket with Use of Fluoride Varnish or Chlorhexidine Gel

    Directory of Open Access Journals (Sweden)

    Manuel Restrepo

    2015-01-01

    Full Text Available The aims of this study were to compare the effectiveness of fluoride varnish and chlorhexidine gel in controlling white spot lesions (WSLs adjacent to orthodontic brackets and to compare the ability of Quantitative Light-Induced Fluorescence (QLF to measure mineral uptake with that of transverse microradiography (TMR. Thirty premolars with artificially induced WSLs were randomly assigned to three groups: (1 two applications of 5% NaF-varnish (F, with one-week interval, (2 two applications of 2% chlorhexidine gel (CHX, with one-week interval, and (3 control (CO, no treatment. QLF was used to measure changes in fluorescence before and after caries induction, 1 week after each application and 1, 2, and 3 months after the last application of F or CHX. TMR was performed to quantify lesion depth and mineral content after caries induction to evaluate the effects of F, CHX, and CO 3 months after the last application of agents. The data were analyzed by repeated measures ANOVA and Tukey’s test. All treatments increased the mineral content during the experimental period; however, F induced faster remineralization than CHX. The correlation between QLF and TMR was significantly moderate. Two applications of fluoride varnish or 2% chlorhexidine gel at one-week intervals were effective in controlling WSLs.

  18. Control of white spot lesion adjacent to orthodontic bracket with use of fluoride varnish or chlorhexidine gel.

    Science.gov (United States)

    Restrepo, Manuel; Bussaneli, Diego G; Jeremias, Fabiano; Cordeiro, Rita C L; Magalhães, Ana C; Palomari Spolidorio, Denise M; Santos-Pinto, Lourdes

    2015-01-01

    The aims of this study were to compare the effectiveness of fluoride varnish and chlorhexidine gel in controlling white spot lesions (WSLs) adjacent to orthodontic brackets and to compare the ability of Quantitative Light-Induced Fluorescence (QLF) to measure mineral uptake with that of transverse microradiography (TMR). Thirty premolars with artificially induced WSLs were randomly assigned to three groups: (1) two applications of 5% NaF-varnish (F), with one-week interval, (2) two applications of 2% chlorhexidine gel (CHX), with one-week interval, and (3) control (CO), no treatment. QLF was used to measure changes in fluorescence before and after caries induction, 1 week after each application and 1, 2, and 3 months after the last application of F or CHX. TMR was performed to quantify lesion depth and mineral content after caries induction to evaluate the effects of F, CHX, and CO 3 months after the last application of agents. The data were analyzed by repeated measures ANOVA and Tukey's test. All treatments increased the mineral content during the experimental period; however, F induced faster remineralization than CHX. The correlation between QLF and TMR was significantly moderate. Two applications of fluoride varnish or 2% chlorhexidine gel at one-week intervals were effective in controlling WSLs.

  19. Cost-effective fabrication of waveguides for PLCs by replication in UV-curable sol-gel material

    Science.gov (United States)

    Gimkiewicz, Christiane; Thiele, Hans D.; Zschokke, Christian; Mahmud-Skender, Sanida; Westenhofer, Susanne; Gale, Michael T.

    2004-08-01

    A new wafer-scale replication process for fabricating buried ridge waveguides for telecom/datacom applications using an uv-curable sol-gel material is proposed. Spin coating of the core material on the replication mould is used to form the waveguide cores with a smooth thin layer. The spin parameters allow an accurate control of the thickness and homogeneity. The bottom-cladding is uv-cast between a substrate and the mould, which is covered by the spun core layer. The ridge waveguide cores are demoulded and buried under a top cladding. This process allows the stacking of several layers of waveguides on top of each other to form two-dimensional waveguide arrays. A specially adapted SUSS mask aligner is used to control the cladding thickness between individual waveguide layers and to align them. A waveguide loss comparable to lithographically fabricated waveguides has been achieved.

  20. Virus replication cycle of white spot syndrome virus in secondary cell cultures from the lymphoid organ of Litopenaeus vannamei.

    Science.gov (United States)

    Li, Wenfeng; Desmarets, Lowiese M B; De Gryse, Gaëtan M A; Theuns, Sebastiaan; Van Tuan, Vo; Van Thuong, Khuong; Bossier, Peter; Nauwynck, Hans J

    2015-09-01

    The replication cycle of white spot syndrome virus (WSSV) was investigated in secondary cell cultures from the lymphoid organ of Litopenaeus vannamei. The secondary cells formed a confluent monolayer at 24 h post-reseeding, and this monolayer could be maintained for 10 days with a viability of 90 %. Binding of WSSV to cells reached a maximum (73 ± 3 % of cells and 4.84 ± 0.2 virus particles per virus-binding cell) at 120 min at 4 °C. WSSV entered cells by endocytosis. The co-localization of WSSV and early endosomes was observed starting from 30 min post-inoculation (p.i.). Double indirect immunofluorescence staining showed that all cell-bound WSSV particles entered these cells in the period between 0 and 60 min p.i. and that the uncoating of WSSV occurred in the same period. After 1 h inoculation at 27 °C, the WSSV nucleocapsid protein VP664 and envelope protein VP28 started to be synthesized in the cytoplasm from 1 and 3 h p.i., and were transported into nuclei from 3 and 6 h p.i., respectively. The percentage of cells that were VP664- and VP28-positive in their nuclei peaked (50 ± 4 %) at 12 h p.i. Quantitative PCR showed that WSSV DNA started to be synthesized from 6 h p.i. In vivo titration of the supernatants showed that the progeny WSSV were released from 12 h p.i. and peaked at 18 h p.i. In conclusion, the secondary cell cultures from the lymphoid organ were proven to be ideal for examination of the replication cycle of WSSV.

  1. 2D-gel spot detection and segmentation based on modified image-aware grow-cut and regional intensity information.

    Science.gov (United States)

    Kostopoulou, E; Katsigiannis, S; Maroulis, D

    2015-10-01

    Proteomics, the study of proteomes, has been increasingly utilized in a wide variety of biological problems. The Two-Dimensional Gel Electrophoresis (2D-PAGE) technique is a powerful proteomics technique aiming at separation of the complex protein mixtures. Spot detection and segmentation are fundamental components of 2D-gel image analysis but remain arduous and difficult tasks. Several software packages and academic approaches are available for 2D-gel image spot detection and segmentation. Each one has its respective advantages and disadvantages and achieves a different level of success in dealing with the challenges of 2D-gel image analysis. A common characteristic of the available methods is their dependency on user intervention in order to achieve optimal results, a process that can lead to subjective and non-reproducible results. In this work, the authors propose a novel spot detection and segmentation methodology for 2D-gel images. This work introduces a novel spot detection and spot segmentation methodology that is based on a multi-thresholding scheme applied on overlapping regions of the image, a custom grow-cut algorithm, a region growing scheme and morphological operators. The performance of the proposed methodology is evaluated on real as well as synthetic 2D-gel images using well established statistical measures, including precision, sensitivity, and their weighted measure, F-measure, as well as volumetric overlap, volumetric error and volumetric overlap error. Experimental results show that the proposed methodology outperforms state-of-the-art software packages and methods proposed in the literature and results in more plausible spot boundaries and more accurate segmentation. The proposed method achieved the highest F-measure (94.8%) for spot detection and the lowest volumetric overlap error (8.3%) for the segmentation process. Evaluation against state-of-the-art 2D-gel image analysis software packages and techniques proposed in the literature

  2. Control of White Spot Lesions with Use of Fluoride Varnish or Chlorhexidine Gel During Orthodontic Treatment A Randomized Clinical Trial.

    Science.gov (United States)

    Restrepo, M; Bussaneli, D G; Jeremias, F; Cordeiro, R C L; Raveli, D B; Magalhães, A C; Candolo, C; Santos-Pinto, L

    2016-01-01

    To compare the effectiveness of fluoride varnish and 2% chlorhexidine gel for controlling active white spot lesions (WSLs) adjacent to orthodontic brackets. Thirty-five orthodontic patients (17.2 ± 2.3 years old) presenting 60 WSLs adjacent to orthodontic brackets were enrolled in this randomized, blind, 3-armed and controlled clinical trial. The patients were randomly allocated to 1 of 3 arms: (1) two applications of 5% NaF varnish- F, with one-week interval, (2) two applications of 2% chlorhexidine gel-CHX, with one-week interval and (3) usual home care-control (CO). The WSLs were scored by using a DIAGNOdent pen. An independent examiner scored the surfaces using Nyvad criteria for caries assessment. A total of thirty patients presenting 51 lesions completed the study. All treatments reduced the fluorescence values during the experimental period; however, F induced faster remineralization than CHX. After 3 months, 70.58 % were inactive considering all groups. DIAGNOdent pen and Nyvad presented a significant correlation. After 3 months of treatment, F, CHX and CO were capable of controlling the WSLs adjacent to the orthodontic brackets. However, the treatment with F was capable of controlling the progression of the WSLs in a shorter period of time.

  3. Determining degradation and synthesis rates of arabidopsis proteins using the kinetics of progressive 15N labeling of two-dimensional gel-separated protein spots.

    Science.gov (United States)

    Li, Lei; Nelson, Clark J; Solheim, Cory; Whelan, James; Millar, A Harvey

    2012-06-01

    The growth and development of plant tissues is associated with an ordered succession of cellular processes that are reflected in the appearance and disappearance of proteins. The control of the kinetics of protein turnover is central to how plants can rapidly and specifically alter protein abundance and thus molecular function in response to environmental or developmental cues. However, the processes of turnover are largely hidden during periods of apparent steady-state protein abundance, and even when proteins accumulate it is unclear whether enhanced synthesis or decreased degradation is responsible. We have used a (15)N labeling strategy with inorganic nitrogen sources coupled to a two-dimensional fluorescence difference gel electrophoresis and mass spectrometry analysis of two-dimensional IEF/SDS-PAGE gel spots to define the rate of protein synthesis (K(S)) and degradation (K(D)) of Arabidopsis cell culture proteins. Through analysis of MALDI-TOF/TOF mass spectra from 120 protein spots, we were able to quantify K(S) and K(D) for 84 proteins across six functional groups and observe over 65-fold variation in protein degradation rates. K(S) and K(D) correlate with functional roles of the proteins in the cell and the time in the cell culture cycle. This approach is based on progressive (15)N labeling that is innocuous for the plant cells and, because it can be used to target analysis of proteins through the use of specific gel spots, it has broad applicability.

  4. Interaction between Kazal serine proteinase inhibitor SPIPm2 and viral protein WSV477 reduces the replication of white spot syndrome virus.

    Science.gov (United States)

    Ponprateep, Sirikwan; Phiwsaiya, Kornsunee; Tassanakajon, Anchalee; Rimphanitchayakit, Vichien

    2013-09-01

    White spot syndrome (WSS) is a viral disease caused by white spot syndrome virus (WSSV) which leads to severe mortality in cultured penaeid shrimp. In response to WSSV infection in Penaeus monodon, a Kazal serine proteinase inhibitor SPIPm2, normally stored in the granules of granular and semi-granular hemocytes is up-regulated and found to deter the viral replication. By using yeast two-hybrid screening, we have identified a viral target protein, namely WSV477. Instead of being a proteinase, the WSV477 was reported to be a Cys2/Cys2-type zinc finger regulatory protein having ATP/GTP-binding activity. In vitro pull down assay confirmed the protein-protein interaction between rSPIPm2 and rWSV477. Confocal laser scanning microscopy demonstrated that the SPIPm2 and WSV477 were co-localized in the cytoplasm of shrimp hemocytes. Using RNA interference, the silencing of WSV477 resulted in down-regulated of viral late gene VP28, the same result obtained with SPIPm2. In this instance, the SPIPm2 does not function as proteinase inhibitor but inhibit the regulatory function of WSV477.

  5. Hepatitis B virus core protein with hot-spot mutations inhibit MxA gene transcription but has no effect on inhibition of virus replication by interferon α.

    Science.gov (United States)

    Zhijian, Yu; Zhen, Huang; Fan, Zhang; Jin, Yang; Qiwen, Deng; Zhongming, Zeng

    2010-10-20

    It has been reported that hepatitis B virus (HBV) core protein (HBc) can inhibit the transcription of human interferon-induced MxA gene. In this study, we investigated whether HBc protein mutations at hot spots (L60V, S87G and I97L) could still inhibit MxA transcription and the potential significance of this inhibition in virus replication in vitro. Our data indicated that the IFN-induced MxA mRNA expression level and MxA promoter activity was significantly down-regulated by mutant protein of HBc(I97L), compared to WT and the other two mutated HBc proteins(L60V or S87G). However, in Huh7 cells stably expressing WT or the mutated HBc proteins (L60V, S87G or I97L), IFN-α could inhibit the extra- and intracellular HBV DNA level and HBsAg secretion to a similar level compared to that in cells transfected with control plasmids. In conclusion, HBc protein with I97L mutation may play an special role in suppressing the transcription of MxA gene. Moreover, the inhibitory effect on MxA gene transcription by the WT or mutated HBc proteins (L60V, S87G and I97L) has no impact on inhibition of HBV replication by IFN-α in Huh7 cells. The clinical significance of the inhibitory effect of MxA gene transcription by HBc protein requires further study.

  6. Development of primary cell cultures from mud crab, Scylla serrata, and their potential as an in vitro model for the replication of white spot syndrome virus.

    Science.gov (United States)

    Deepika, A; Makesh, M; Rajendran, K V

    2014-01-01

    Primary cell cultures were developed from haemocytes and testis of Scylla serrata. Haemocytes were collected from live animals and cultured in double-strength L-15 medium (2× L-15) prepared in crab saline, supplemented with 5% foetal bovine serum and antibiotic-antimycotic solution (penicillin 100 U/mL, streptomycin 100 μg/mL and amphotericin B 0.25 μg/mL) with osmolality adjusted to 894 mOsm/kg. The haemocytes adhered within 2 h after seeding and showed proliferation up to 72 h. The disaggregated testis tissue fragments were seeded in 3× L-15 supplemented with non-essential amino acid mixture, lipid concentrate and antibiotic-antimycotic solution, with osmolality adjusted to 1,035 mOsm/kg with crab saline. Cells from the testis could be subcultured and maintained up to 21 d as suspension culture. Different dilutions of white spot syndrome virus (WSSV) inoculum (known virus copy number) prepared from infected Penaeus monodon were inoculated in the cultured cells, and the cytopathic effects like detachment, rounding of cells and clear areas of depleted cells were observed after 48 h in haemocyte cultures. However, WSSV-exposed testis cells did not show any obvious change until 72 h post-infection. WSSV was detected in both haemocyte and testis cultures at different time-points of infection by conventional and real-time PCR using WSSV-specific primers. The transcripts of WSSV were found to be much higher in haemocytes than in testis culture. The virus harvested from the cultured haemocytes after three passages could infect healthy P. monodon. The present study showed that mud crab haemocyte culture can support WSSV replication, and it can be used as an in vitro tool for WSSV replication.

  7. Effect of multiple infections with white spot syndrome virus and Vibrio anguillarum on Pacific white shrimp Litopenaeus vannamei (L.): mortality and viral replication.

    Science.gov (United States)

    Jang, I K; Qiao, G; Kim, S-K

    2014-10-01

    Multiple infections are commonly found in practical shrimp culture and may cause more serious consequences than infections by one pathogen only. Therefore, this study was conducted to evaluate the effect of multiple infections with white spot syndrome virus (WSSV) and Vibrio anguillarum on Pacific white shrimp Litopenaeus vannamei (L.), mortality, WSSV replication in vivo and host immune response. In the WSSV single-infection group (WSSV load, 2 × 10(2) copies μL(-1)), mean cumulative mortality was 29.2%. In the V. anguillarum single-infection group, cumulative mortality was 12.5% when shrimp were challenged by 10(5) CFU mL(-1) of bacteria. In the co- and super-infection groups, 37.5% and 50% cumulative mortalities, respectively, were observed at a lower bacterial concentration of 10(3) CFU mL(-1), suggesting that shrimp with multiple infections died earlier and more frequently than singly infected shrimp. WSSV load after injection was tracked over time by TaqMan quantitative PCR. WSSV load increased more rapidly in the multiple-infection groups than in the single-infection group. Additionally, mRNA expression of the genes encoding prophenoloxidase 1 and 2, which are closely involved in innate immunity in shrimp, was down-regulated more extensively in multiple-infection groups than in single-infection groups, as indicated by quantitative reverse-transcription PCR.

  8. Replication of butterfly wing and natural lotus leaf structures by nanoimprint on silica sol-gel films

    Energy Technology Data Exchange (ETDEWEB)

    Saison, Tamar; Peroz, Christophe; Chauveau, Vanessa; Sondergard, Elin; Arribart, Herve [Unite mixte CNRS/Saint Gobain Saint Gobain Recherche, BP135, 93303 Aubervilliers (France); Berthier, Serge [Institut des Nanosciences de Paris, UMR 7588, CNRS, Universite Pierre et Marie Curie-Paris 6, 140 rue Lourmel, 75015 Paris (France)], E-mail: cperoz@lbl.gov

    2008-12-01

    An original and low cost method for the fabrication of patterned surfaces bioinspired from butterfly wings and lotus leaves is presented. Silica-based sol-gel films are thermally imprinted from elastomeric molds to produce stable structures with superhydrophobicity values as high as 160 deg. water contact angle. The biomimetic surfaces are demonstrated to be tuned from superhydrophobic to superhydrophilic by annealing between 200 deg. C and 500 deg. C.

  9. Replication of butterfly wing and natural lotus leaf structures by nanoimprint on silica sol-gel films.

    Science.gov (United States)

    Saison, Tamar; Peroz, Christophe; Chauveau, Vanessa; Berthier, Serge; Sondergard, Elin; Arribart, Hervé

    2008-12-01

    An original and low cost method for the fabrication of patterned surfaces bioinspired from butterfly wings and lotus leaves is presented. Silica-based sol-gel films are thermally imprinted from elastomeric molds to produce stable structures with superhydrophobicity values as high as 160 degrees water contact angle. The biomimetic surfaces are demonstrated to be tuned from superhydrophobic to superhydrophilic by annealing between 200 degrees C and 500 degrees C.

  10. Formation of replicating saponite from a gel in the presence of oxalate: implications for the formation of clay minerals in carbonaceous chondrites and the origin of life

    Science.gov (United States)

    Schumann, Dirk; Hartman, Hyman; Eberl, Dennis D.; Sears, S. Kelly; Hesse, Reinhard; Vali, Hojatollah

    2012-01-01

    The potential role of clay minerals in the abiotic origin of life has been the subject of ongoing debate for the past several decades. At issue are the clay minerals found in a class of meteorites known as carbonaceous chondrites. These clay minerals are the product of aqueous alteration of anhydrous mineral phases, such as olivine and orthopyroxene, that are often present in the chondrules. Moreover, there is a strong correlation in the occurrence of clay minerals and the presence of polar organic molecules. It has been shown in laboratory experiments at low temperature and ambient pressure that polar organic molecules, such as the oxalate found in meteorites, can catalyze the crystallization of clay minerals. In this study, we show that oxalate is a robust catalyst in the crystallization of saponite, an Al- and Mg-rich, trioctahedral 2:1 layer silicate, from a silicate gel at 60°C and ambient pressure. High-resolution transmission electron microscopy analysis of the saponite treated with octadecylammonium (n(C)=18) cations revealed the presence of 2:1 layer structures that have variable interlayer charge. The crystallization of these differently charged 2:1 layer silicates most likely occurred independently. The fact that 2:1 layer silicates with variable charge formed in the same gel has implications for our understanding of the origin of life, as these 2:1 clay minerals most likely replicate by a mechanism of template-catalyzed polymerization and transmit the charge distribution from layer to layer. If polar organic molecules like oxalate can catalyze the formation of clay-mineral crystals, which in turn promote clay microenvironments and provide abundant adsorption sites for other organic molecules present in solution, the interaction among these adsorbed molecules could lead to the polymerization of more complex organic molecules like RNA from nucleotides on early Earth.

  11. Formation of replicating saponite from a gel in the presence of oxalate: implications for the formation of clay minerals in carbonaceous chondrites and the origin of life.

    Science.gov (United States)

    Schumann, Dirk; Hartman, Hyman; Eberl, Dennis D; Sears, S Kelly; Hesse, Reinhard; Vali, Hojatollah

    2012-06-01

    The potential role of clay minerals in the abiotic origin of life has been the subject of ongoing debate for the past several decades. At issue are the clay minerals found in a class of meteorites known as carbonaceous chondrites. These clay minerals are the product of aqueous alteration of anhydrous mineral phases, such as olivine and orthopyroxene, that are often present in the chondrules. Moreover, there is a strong correlation in the occurrence of clay minerals and the presence of polar organic molecules. It has been shown in laboratory experiments at low temperature and ambient pressure that polar organic molecules, such as the oxalate found in meteorites, can catalyze the crystallization of clay minerals. In this study, we show that oxalate is a robust catalyst in the crystallization of saponite, an Al- and Mg-rich, trioctahedral 2:1 layer silicate, from a silicate gel at 60°C and ambient pressure. High-resolution transmission electron microscopy analysis of the saponite treated with octadecylammonium (n(C)=18) cations revealed the presence of 2:1 layer structures that have variable interlayer charge. The crystallization of these differently charged 2:1 layer silicates most likely occurred independently. The fact that 2:1 layer silicates with variable charge formed in the same gel has implications for our understanding of the origin of life, as these 2:1 clay minerals most likely replicate by a mechanism of template-catalyzed polymerization and transmit the charge distribution from layer to layer. If polar organic molecules like oxalate can catalyze the formation of clay-mineral crystals, which in turn promote clay microenvironments and provide abundant adsorption sites for other organic molecules present in solution, the interaction among these adsorbed molecules could lead to the polymerization of more complex organic molecules like RNA from nucleotides on early Earth.

  12. Shrimp miR-10a Is Co-opted by White Spot Syndrome Virus to Increase Viral Gene Expression and Viral Replication

    Science.gov (United States)

    Huang, Jiun-Yan; Kang, Shih-Ting; Chen, I-Tung; Chang, Li-Kwan; Lin, Shih-Shun; Kou, Guang-Hsiung; Chu, Chia-Ying; Lo, Chu-Fang

    2017-01-01

    Members of the microRNA miR-10 family are highly conserved and play many important roles in diverse biological mechanisms, including immune-related responses and cancer-related processes in certain types of cancer. In this study, we found the most highly upregulated shrimp microRNA from Penaeus vannamei during white spot syndrome virus (WSSV) infection was miR-10a. After confirming the expression level of miR-10a by northern blot and quantitative RT-PCR, an in vivo experiment showed that the viral copy number was decreased in miR-10a-inhibited shrimp. We found that miR-10a targeted the 5′ untranslated region (UTR) of at least three viral genes (vp26, vp28, and wssv102), and plasmids that were controlled by the 5′ UTR of these genes produced enhanced luciferase signals in transfected SF9 cells. These results suggest a previously unreported role for shrimp miR-10a and even a new type of host–virus interaction, whereby a co-opts the key cellular regulator miR-10a to globally enhance the translation of viral proteins. PMID:28932224

  13. Comparative Two-Dimensional Fluorescence Gel Electrophoresis.

    Science.gov (United States)

    Ackermann, Doreen; König, Simone

    2018-01-01

    Two-dimensional comparative fluorescence gel electrophoresis (CoFGE) uses an internal standard to increase the reproducibility of coordinate assignment for protein spots visualized on 2D polyacrylamide gels. This is particularly important for samples, which need to be compared without the availability of replicates and thus cannot be studied using differential gel electrophoresis (DIGE). CoFGE corrects for gel-to-gel variability by co-running with the sample proteome a standardized marker grid of 80-100 nodes, which is formed by a set of purified proteins. Differentiation of reference and analyte is possible by the use of two fluorescent dyes. Variations in the y-dimension (molecular weight) are corrected by the marker grid. For the optional control of the x-dimension (pI), azo dyes can be used. Experiments are possible in both vertical and horizontal (h) electrophoresis devices, but hCoFGE is much easier to perform. For data analysis, commercial software capable of warping can be adapted.

  14. Analysis of branched DNA replication and recombination intermediates from prokaryotic cells by two-dimensional (2D) native-native agarose gel electrophoresis.

    Science.gov (United States)

    Robinson, Nicholas P

    2013-01-01

    Branched DNA molecules are generated by the essential processes of replication and recombination. Owing to their distinctive extended shapes, these intermediates migrate differently from linear double-stranded DNA under certain electrophoretic conditions. However, these branched species exist in the cell at much low abundance than the bulk linear DNA. Consequently, branched molecules cannot be visualized by conventional electrophoresis and ethidium bromide staining. Two-dimensional native-native agarose electrophoresis has therefore been developed as a method to facilitate the separation and visualization of branched replication and recombination intermediates. A wide variety of studies have employed this technique to examine branched molecules in eukaryotic, archaeal, and bacterial cells, providing valuable insights into how DNA is duplicated and repaired in all three domains of life.

  15. Single-cell gel electrophoresis assay in the ten spotted live-bearer fish, Cnesterodon decemmaculatus (Jenyns, 1842), as bioassay for agrochemical-induced genotoxicity.

    Science.gov (United States)

    Vera-Candioti, Josefina; Soloneski, Sonia; Larramendy, Marcelo L

    2013-12-01

    The ability of two 48 percent chlorpyrifos-based insecticides (Lorsban* 48E® and CPF Zamba®), two 50 percent pirimicarb-based insecticides (Aficida® and Patton Flow®), and two 48 percent glyphosate-based herbicides (Panzer® and Credit®) to induce DNA single-strand breaks in peripheral blood erythrocytes of Cnesterodon decemmaculatus (Jenyns, 1842) (Pisces, Poeciliidae) exposed under laboratory conditions was evaluated by the single-cell gel electrophoresis (SCGE) assay. In those fish exposed to Lorsban* 48E®, CPF Zamba®, Aficida®, Patton Flow®, Credit®, and Panzer®, a significant increase of the genetic damage was observed for all formulations regardless of the harvesting time. This genotoxic effect was achieved by an enhancement of Type II-IV comets and a concomitant decrease of Type 0-I comets over control values. A regression analysis revealed that the damage varied as a negative function of the exposure time in those Lorsban* 48E®- and Aficida®-treated fish. On the other hand, a positive correlation between damage increase and exposure time was achieved after Patton Flow® and Credit® treatment. Finally, no correlation was observed between increase in the genetic damage and exposure time after treatment with CPF Zamba® or Panzer®. These results highlight that all agrochemicals inflict primary genotoxic damage at the DNA level at sublethal concentrations, regardless of the exposure time of the aquatic organisms under study, at least within a period of 96 h of treatment.

  16. c-Jun N-terminal kinases 3 (JNK3) from orange-spotted grouper, Epinephelus coioides, inhibiting the replication of Singapore grouper iridovirus (SGIV) and SGIV-induced apoptosis.

    Science.gov (United States)

    Guo, Minglan; Wei, Jingguang; Zhou, Yongcan; Qin, Qiwei

    2016-12-01

    C-Jun N-terminal kinases (JNKs), a subgroup of serine-threonine protein kinases that activated by phosphorylation, are involve in physiological and pathophysiological processes. JNK3 is one of JNK proteins involved in JNK3 signaling transduction. In the present study, two JNK3 isoforms, Ec-JNK3 X1 and Ec-JNK3 X2, were cloned from orange-spotted grouper, Epinephelus coioides. Both Ec-JNK3 X1 and Ec-JNK3 X2 were mainly expressed in liver, gill, skin, brain and muscle of juvenile grouper. The relative expression of Ec-JNK3 X2 mRNA was much higher in muscle and gill than that of Ec-JNK3 X1. Isoform-specific immune response to challenges was revealed by the expression profiles in vivo. Immunofluorescence staining indicated that JNK3 was localized in the cytoplasm of grouper spleen (GS) cells and shown immune response to SGIV infection in vitro. Over-expressing Ec-JNK3 X1 and/or Ec-JNK3 X2 inhibited the SGIV infection and replication and the SGIV-induced apoptosis. To achieve the antiviral and anti-apoptosis activities, JNK3 promoted the activation of genes ISRE and type I IFN in the antiviral IFN signaling pathway, and inhibited the activation of transcription factors NF-κB and p53 relating to apoptosis, respectively. Ec-JNK3 X2 showed stronger activities in antivirus and anti-apoptosis than that of Ec-JNK3 X1. Our results not only define the characterization of JNK3 but also reveal new immune functions and the molecular mechanisms of JNK3 on iridoviruses infection and the virus-induced apoptosis.

  17. Liver spots

    Science.gov (United States)

    Liver spots are changes in skin color that occur in older skin. The coloring may be due to aging, exposure to the sun or other sources of ultraviolet light, or causes that are not known. Liver spots are very common after age 40. They occur ...

  18. Spotted inflation

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Tomohiro, E-mail: matsuda@sit.ac.jp [Laboratory of Physics, Saitama Institute of Technology, Fusaiji, Okabe-machi, Saitama 369-0293 (Japan)

    2010-11-01

    We describe new scenarios for generating curvature perturbations when inflaton (curvaton) has significant interactions. We consider a ''spot'', which arises from interactions associated with an enhanced symmetric point (ESP) on the trajectory. Our first example uses the spot to induce a gap in the field equation. We observe that the gap in the field equation may cause generation of curvature perturbation if it does not appear simultaneous in space. The mechanism is similar to the scenario of inhomogeneous phase transition. Then we observe that the spot interactions may initiate warm inflation in the cold Universe. Creation of cosmological perturbation is discussed in relation to the inflaton dynamics and the modulation associated with the spot interactions.

  19. SPOT Program

    Science.gov (United States)

    Smith, Jason T.; Welsh, Sam J.; Farinetti, Antonio L.; Wegner, Tim; Blakeslee, James; Deboeck, Toni F.; Dyer, Daniel; Corley, Bryan M.; Ollivierre, Jarmaine; Kramer, Leonard; Zimmerman, Patrick L.; Khatri, Reshma

    2010-01-01

    A Spacecraft Position Optimal Tracking (SPOT) program was developed to process Global Positioning System (GPS) data, sent via telemetry from a spacecraft, to generate accurate navigation estimates of the vehicle position and velocity (state vector) using a Kalman filter. This program uses the GPS onboard receiver measurements to sequentially calculate the vehicle state vectors and provide this information to ground flight controllers. It is the first real-time ground-based shuttle navigation application using onboard sensors. The program is compact, portable, self-contained, and can run on a variety of UNIX or Linux computers. The program has a modular objec-toriented design that supports application-specific plugins such as data corruption remediation pre-processing and remote graphics display. The Kalman filter is extensible to additional sensor types or force models. The Kalman filter design is also strong against data dropouts because it uses physical models from state and covariance propagation in the absence of data. The design of this program separates the functionalities of SPOT into six different executable processes. This allows for the individual processes to be connected in an a la carte manner, making the feature set and executable complexity of SPOT adaptable to the needs of the user. Also, these processes need not be executed on the same workstation. This allows for communications between SPOT processes executing on the same Local Area Network (LAN). Thus, SPOT can be executed in a distributed sense with the capability for a team of flight controllers to efficiently share the same trajectory information currently being computed by the program. SPOT is used in the Mission Control Center (MCC) for Space Shuttle Program (SSP) and International Space Station Program (ISSP) operations, and can also be used as a post -flight analysis tool. It is primarily used for situational awareness, and for contingency situations.

  20. TV spots' impact.

    Science.gov (United States)

    El-bakly, S

    1994-09-01

    The Information, Education and Communication (IEC) Center of the State Information Service was established in 1979 for the purpose of providing information to the people on the population issue. The Ministry of Information has accorded the State Information Service free TV and radio air time for family planning dramas and spots. In the early years information campaigns were organized to make people aware of the population problem by slogans, songs, and cartoons. Around 1984 misconceptions about family planning and contraceptives were attacked through a number of TV and radio spots. A few years later 21 spots on specific contraceptive methods were broadcast which were aired for three years over 3000 times. They were extremely successful. The impact of these TV spots was one of the major reasons why the contraceptive prevalence rate increased from 30% in 1984 to 38% in 1988 and 47% in 1992. Spots were also broadcast about the social implications of large families. The TV soap opera "And The Nile Flows On", with the family planning message interwoven into it, was very well received by the target audience. A program entitled "Wedding of the Month" features couples who know family planning well. The most successful radio program is a 15-20 minute long quiz show for residents of the villages where the Select Villages Project is being implemented. The State Information Service has 60 local information centers in the 26 governorates of Egypt that make plans for the family planning campaign. In 1992 the Minya Initiative, a family planning project was implemented in the Minya Governorate. As a result, the contraceptive prevalence rate rose from 22% to 30% over 18 months. A new project, the Select Village Project, was developed in 1993 that replicates the Minya Initiative on the village level in other governorates. This new project that was implemented in sixteen governorates.

  1. Database Replication

    CERN Document Server

    Kemme, Bettina

    2010-01-01

    Database replication is widely used for fault-tolerance, scalability and performance. The failure of one database replica does not stop the system from working as available replicas can take over the tasks of the failed replica. Scalability can be achieved by distributing the load across all replicas, and adding new replicas should the load increase. Finally, database replication can provide fast local access, even if clients are geographically distributed clients, if data copies are located close to clients. Despite its advantages, replication is not a straightforward technique to apply, and

  2. Mongolian spots

    Directory of Open Access Journals (Sweden)

    Divya Gupta

    2013-01-01

    Full Text Available Mongolian spots (MS are birthmarks that are present at birth and their most common location is sacrococcygeal or lumbar area. Lesions may be single or multiple and usually involve < 5% total body surface area. They are macular and round, oval or irregular in shape. The color varies from blue to greenish, gray, black or a combination of any of the above. The size varies from few to more than 20 centimetres. Pigmentation is most intense at the age of one year and gradually fades thereafter. It is rarely seen after the age of 6 years. Aberrant MS over occiput, temple, mandibular area, shoulders and limbs may be confused with other dermal melanocytoses and bruises secondary to child abuse, thus necessitating documentation at birth. Although regarded as benign, recent data suggest that MS may be associated with inborn errors of metabolism and neurocristopathies. Mongolian spots usually resolve by early childhood and hence no treatment is generally needed if they are located in the sacral area. However, sometimes it may be required for extrasacral lesions for cosmesis.

  3. Explorative data analysis of two-dimensional electrophoresis gels

    DEFF Research Database (Denmark)

    Schultz, J.; Gottlieb, D.M.; Petersen, Marianne Kjerstine

    2004-01-01

    Methods for classification of two-dimensional (2-DE) electrophoresis gels based on multivariate data analysis are demonstrated. Two-dimensional gels of ten wheat varieties are analyzed and it is demonstrated how to classify the wheat varieties in two qualities and a method for initial screening...... of gels is presented. First, an approach is demonstrated in which no prior knowledge of the separated proteins is used. Alignment of the gels followed by a simple transformation of data makes it possible to analyze the gels in an automated explorative manner by principal component analysis, to determine...... if the gels should be further analyzed. A more detailed approach is done by analyzing spot volume lists by principal components analysis and partial least square regression. The use of spot volume data offers a mean to investigate the spot pattern and link the classified protein patterns to distinct spots...

  4. Spot table - RPD | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available ended gel image of the spot. Mass Spectrometry Accession No. Accession No. of homologous protein by Mascot Analysis. Mass Spectrometr...y Homologous Protein Definition of homologous protein by Mascot Analysis. Mass Spectrometry

  5. Rocky Mountain Spotted Fever

    Science.gov (United States)

    ... facebook share with twitter share with linkedin Rocky Mountain Spotted Fever Rocky Mountain spotted fever is a ... New Mexico. Why Is the Study of Rocky Mountain Spotted Fever a Priority for NIAID? Tickborne diseases ...

  6. Are 'hot spots' hot spots?

    Science.gov (United States)

    Foulger, Gillian R.

    2012-07-01

    The term 'hot spot' emerged in the 1960s from speculations that Hawaii might have its origins in an unusually hot source region in the mantle. It subsequently became widely used to refer to volcanic regions considered to be anomalous in the then-new plate tectonic paradigm. It carried with it the implication that volcanism (a) is emplaced by a single, spatially restricted, mongenetic melt-delivery system, assumed to be a mantle plume, and (b) that the source is unusually hot. This model has tended to be assumed a priori to be correct. Nevertheless, there are many geological ways of testing it, and a great deal of work has recently been done to do so. Two fundamental problems challenge this work. First is the difficulty of deciding a 'normal' mantle temperature against which to compare estimates. This is usually taken to be the source temperature of mid-ocean ridge basalts (MORBs). However, Earth's surface conduction layer is ˜200 km thick, and such a norm is not appropriate if the lavas under investigation formed deeper than the 40-50 km source depth of MORB. Second, methods for estimating temperature suffer from ambiguity of interpretation with composition and partial melt, controversy regarding how they should be applied, lack of repeatability between studies using the same data, and insufficient precision to detect the 200-300 °C temperature variations postulated. Available methods include multiple seismological and petrological approaches, modelling bathymetry and topography, and measuring heat flow. Investigations have been carried out in many areas postulated to represent either (hot) plume heads or (hotter) tails. These include sections of the mid-ocean spreading ridge postulated to include ridge-centred plumes, the North Atlantic Igneous Province, Iceland, Hawaii, oceanic plateaus, and high-standing continental areas such as the Hoggar swell. Most volcanic regions that may reasonably be considered anomalous in the simple plate-tectonic paradigm have been

  7. Rocky Mountain spotted fever

    Science.gov (United States)

    ... Mountain spotted fever is caused by the bacteria Rickettsia rickettsii (R. Rickettsii) , which is carried by ticks. ... Saunders; 2014:chap 212. Walker DH, Blaton LS. Rickettsia rickettsii and other spotted fever group rickettsiae (Rocky ...

  8. Replicative Intermediates of Human Papillomavirus Type 11 in Laryngeal Papillomas: Site of Replication Initiation and Direction of Replication

    Science.gov (United States)

    Auborn, K. J.; Little, R. D.; Platt, T. H. K.; Vaccariello, M. A.; Schildkraut, C. L.

    1994-07-01

    We have examined the structures of replication intermediates from the human papillomavirus type 11 genome in DNA extracted from papilloma lesions (laryngeal papillomas). The sites of replication initiation and termination utilized in vivo were mapped by using neutral/neutral and neutral/alkaline two-dimensional agarose gel electrophoresis methods. Initiation of replication was detected in or very close to the upstream regulatory region (URR; the noncoding, regulatory sequences upstream of the open reading frames in the papillomavirus genome). We also show that replication forks proceed bidirectionally from the origin and converge 180circ opposite the URR. These results demonstrate the feasibility of analysis of replication of viral genomes directly from infected tissue.

  9. New Approach for Segmentation and Quantification of Two-Dimensional Gel Electrophoresis Images

    DEFF Research Database (Denmark)

    Anjo, Antonio dos; Laurell Blom Møller, Anders; Ersbøll, Bjarne Kjær;

    2011-01-01

    Motivation: Detection of protein spots in two-dimensional gel electrophoresis images (2-DE) is a very complex task and current approaches addressing this problem still suffer from significant shortcomings. When quantifying a spot, most of the current software applications include a lot of backgro......Motivation: Detection of protein spots in two-dimensional gel electrophoresis images (2-DE) is a very complex task and current approaches addressing this problem still suffer from significant shortcomings. When quantifying a spot, most of the current software applications include a lot....... Results: Five sections from different gels are used to test the performance of the presented method concerning the detection of protein spots, and three gel sections are used to test the quantification of sixty protein spots. Comparisons with a state-of-the-art commercial software and an academic state...

  10. Archaeal DNA replication.

    Science.gov (United States)

    Kelman, Lori M; Kelman, Zvi

    2014-01-01

    DNA replication is essential for all life forms. Although the process is fundamentally conserved in the three domains of life, bioinformatic, biochemical, structural, and genetic studies have demonstrated that the process and the proteins involved in archaeal DNA replication are more similar to those in eukaryal DNA replication than in bacterial DNA replication, but have some archaeal-specific features. The archaeal replication system, however, is not monolithic, and there are some differences in the replication process between different species. In this review, the current knowledge of the mechanisms governing DNA replication in Archaea is summarized. The general features of the replication process as well as some of the differences are discussed.

  11. Replicative intermediates of maize streak virus found during leaf development.

    Science.gov (United States)

    Erdmann, Julia B; Shepherd, Dionne N; Martin, Darren P; Varsani, Arvind; Rybicki, Edward P; Jeske, Holger

    2010-04-01

    Geminiviruses of the genera Begomovirus and Curtovirus utilize three replication modes: complementary-strand replication (CSR), rolling-circle replication (RCR) and recombination-dependent replication (RDR). Using two-dimensional gel electrophoresis, we now show for the first time that maize streak virus (MSV), the type member of the most divergent geminivirus genus, Mastrevirus, does the same. Although mastreviruses have fewer regulatory genes than other geminiviruses and uniquely express their replication-associated protein (Rep) from a spliced transcript, the replicative intermediates of CSR, RCR and RDR could be detected unequivocally within infected maize tissues. All replicative intermediates accumulated early and, to varying degrees, were already present in the shoot apex and leaves at different maturation stages. Relative to other replicative intermediates, those associated with RCR increased in prevalence during leaf maturation. Interestingly, in addition to RCR-associated DNA forms seen in other geminiviruses, MSV also apparently uses dimeric open circular DNA as a template for RCR.

  12. Two-Dimensional Gel Electrophoresis Image Analysis via Dedicated Software Packages.

    Science.gov (United States)

    Maurer, Martin H

    2016-01-01

    Analyzing two-dimensional gel electrophoretic images is supported by a number of freely and commercially available software. Although the respective program is highly specific, all the programs follow certain standardized algorithms. General steps are: (1) detecting and separating individual spots, (2) subtracting background, (3) creating a reference gel and (4) matching the spots to the reference gel, (5) modifying the reference gel, (6) normalizing the gel measurements for comparison, (7) calibrating for isoelectric point and molecular weight markers, and moreover, (8) constructing a database containing the measurement results and (9) comparing data by statistical and bioinformatic methods.

  13. Thermoresponsive Gels

    Directory of Open Access Journals (Sweden)

    M. Joan Taylor

    2017-01-01

    Full Text Available Thermoresponsive gelling materials constructed from natural and synthetic polymers can be used to provide triggered action and therefore customised products such as drug delivery and regenerative medicine types as well as for other industries. Some materials give Arrhenius-type viscosity changes based on coil to globule transitions. Others produce more counterintuitive responses to temperature change because of agglomeration induced by enthalpic or entropic drivers. Extensive covalent crosslinking superimposes complexity of response and the upper and lower critical solution temperatures can translate to critical volume temperatures for these swellable but insoluble gels. Their structure and volume response confer advantages for actuation though they lack robustness. Dynamic covalent bonding has created an intermediate category where shape moulding and self-healing variants are useful for several platforms. Developing synthesis methodology—for example, Reversible Addition Fragmentation chain Transfer (RAFT and Atomic Transfer Radical Polymerisation (ATRP—provides an almost infinite range of materials that can be used for many of these gelling systems. For those that self-assemble into micelle systems that can gel, the upper and lower critical solution temperatures (UCST and LCST are analogous to those for simpler dispersible polymers. However, the tuned hydrophobic-hydrophilic balance plus the introduction of additional pH-sensitivity and, for instance, thermochromic response, open the potential for coupled mechanisms to create complex drug targeting effects at the cellular level.

  14. Proteome analysis of barley seeds: Identification of major proteins from two-dimensional gels (pl 4-7)

    DEFF Research Database (Denmark)

    Østergaard, O.; Finnie, Christine; Laugesen, S.;

    2004-01-01

    -soluble proteins in extracts of mature barley (Hordeum vulgare) seeds and to follow their fate during germination. About 1200 and 600 spots of p/ 4-7 were detected on 2-D gels by silver staining and colloidal Coomassie Brilliant Blue staining, respectively. About 300 spots were selected for in-gel digestion...

  15. Spot Matching of 2-DE Images Using Distance, Intensity, and Pattern Information.

    Science.gov (United States)

    Xin, Hua-Mei; Zhu, Yuemin

    2016-01-01

    The analysis of a large number of two-dimensional gel electrophoresis (2-DE) images requires developing automatic methods. In such analyses, spot matching plays a fundamental role, in particular for the identification of proteins. We describe a simple and accurate method which allows to automatically and accurately match spots in 2-DE images. The method consists of simultaneously exploiting the distance between the spots, their intensity, and the pattern formed by their spatial configuration.

  16. Spotted Seal Distribution Map

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains GIS layers that depict the known spatial distributions (i.e., ranges) and reported breeding areas of spotted seals (Phoca largha). It was...

  17. Mononucleosis spot test

    Science.gov (United States)

    Monospot test; Heterophile antibody test; Heterophile agglutination test; Paul-Bunnell test; Forssman antibody test ... The mononucleosis spot test is done when symptoms of mononucleosis are ... Fatigue Fever Large spleen (possibly) Sore throat Tender ...

  18. An algorithm for automatic evaluation of the spot quality in two-color DNA microarray experiments

    Directory of Open Access Journals (Sweden)

    Barillot Emmanuel

    2005-12-01

    Full Text Available Abstract Background Although DNA microarray technologies are very powerful for the simultaneous quantitative characterization of thousands of genes, the quality of the obtained experimental data is often far from ideal. The measured microarrays images represent a regular collection of spots, and the intensity of light at each spot is proportional to the DNA copy number or to the expression level of the gene whose DNA clone is spotted. Spot quality control is an essential part of microarray image analysis, which must be carried out at the level of individual spot identification. The problem is difficult to formalize due to the diversity of instrumental and biological factors that can influence the result. Results For each spot we estimate the ratio of measured fluorescence intensities revealing differential gene expression or change in DNA copy numbers between the test and control samples. We also define a set of quality characteristics and a model for combining these characteristics into an overall spot quality value. We have developed a training procedure to evaluate the contribution of each individual characteristic in the overall quality. This procedure uses information available from replicated spots, located in the same array or over a set of replicated arrays. It is assumed that unspoiled replicated spots must have very close ratios, whereas poor spots yield greater diversity in the obtained ratio estimates. Conclusion The developed procedure provides an automatic tool to quantify spot quality and to identify different types of spot deficiency occurring in DNA microarray technology. Quality values assigned to each spot can be used either to eliminate spots or to weight contribution of each ratio estimate in follow-up analysis procedures.

  19. Low-cost two-dimensional gel densitometry.

    Science.gov (United States)

    Levenson, R M; Maytin, E V; Young, D A

    1986-11-01

    A major obstacle to full utilization of the powerful technique of two-dimensional (2-D) gel electrophoresis is the expense and complexity of quantifying the results. Using an analog-to-digital converter already present in the widely available Commodore 64 or Commodore 128 microcomputer, we have developed a 2-D gel densitometer (GELSCAN) which adds only $20.00 to the cost of the Commodore system (currently around $700.00). The system is designed to work with autoradiograms of 2-D gels. Spots of interest are identified visually and then positioned manually over a light source. A pinhole photoelectric sensor mounted in a hand-held, Plexiglas holder, or "mouse," is briefly rubbed over each spot. Maximum density of the spot is determined and its value is converted to counts per minute via an internal calibration curve which corrects for the nonlinear response of film to radiation. Local spot backgrounds can be subtracted and values can be normalized between gels to adjust for variation in amount of radioactivity applied or in exposure time. Reproducibility is excellent and the technique has some practical as well as theoretical advantages over other more complicated approaches to 2-D gel densitometry. In addition, the GELSCAN system can also be used for scanning individual bands in 1-D gels, quantitation of "dot-blot" autoradiograms and other tasks involving transmission densitometry.

  20. Multivariate data analysis of two-dimensional gel electrophoresis protein patterns from few samples

    DEFF Research Database (Denmark)

    Jensen, Kristina Nedenskov; Jessen, Flemming; Jørgensen, Bo

    2008-01-01

    One application of 2D gel electrophoresis is to reveal differences in protein pattern between two or more groups of individuals, attributable to their group membership. Multivariate data analytical methods are useful in pinpointing the spots relevant for discrimination by focusing not only...... on single spot differences, but on the covariance structure between proteins. However, their outcome is dependent on data scaling, and they may fail in producing valid multivariate models due to the much higher number of "irrelevant" spots present in the gels. The case where only few gels are available...

  1. Analysis of tomato spotted wilt virus genome transcription

    NARCIS (Netherlands)

    Knippenberg, van I.C.

    2005-01-01

    Tomato spotted wilt virus (TSWV) is the type species of the genus Tospovirus within the Bunyaviridae, a family of segmented negative strand RNA viruses. Although much ground has been covered in the past two decades, many questions concerning the mechanism of replication and transcription of this

  2. Analysis of tomato spotted wilt virus genome transcription

    NARCIS (Netherlands)

    Knippenberg, van I.C.

    2005-01-01

    Tomato spotted wilt virus (TSWV) is the type species of the genus Tospovirus within the Bunyaviridae, a family of segmented negative strand RNA viruses. Although much ground has been covered in the past two decades, many questions concerning the mechanism of replication and transcription of this imp

  3. Replication Restart in Bacteria.

    Science.gov (United States)

    Michel, Bénédicte; Sandler, Steven J

    2017-07-01

    In bacteria, replication forks assembled at a replication origin travel to the terminus, often a few megabases away. They may encounter obstacles that trigger replisome disassembly, rendering replication restart from abandoned forks crucial for cell viability. During the past 25 years, the genes that encode replication restart proteins have been identified and genetically characterized. In parallel, the enzymes were purified and analyzed in vitro, where they can catalyze replication initiation in a sequence-independent manner from fork-like DNA structures. This work also revealed a close link between replication and homologous recombination, as replication restart from recombination intermediates is an essential step of DNA double-strand break repair in bacteria and, conversely, arrested replication forks can be acted upon by recombination proteins and converted into various recombination substrates. In this review, we summarize this intense period of research that led to the characterization of the ubiquitous replication restart protein PriA and its partners, to the definition of several replication restart pathways in vivo, and to the description of tight links between replication and homologous recombination, responsible for the importance of replication restart in the maintenance of genome stability. Copyright © 2017 American Society for Microbiology.

  4. Replication intermediate analysis confirms that chromosomal replication origin initiates from an unusual intergenic region in Caulobacter crescentus.

    Science.gov (United States)

    Brassinga, A K; Marczynski, G T

    2001-11-01

    The alpha-proteobacterium Caulobacter crescentus possesses a developmental cell cycle that restricts chromosome replication to a stalked cell type. The proposed C.crescentus chromosome replication origin (Cori) lies between hemE and RP001, an unusual intergenic region not previously associated with bacterial replication origins, although a similar genomic arrangement is also present at the putative replication origin in the related bacterium Rickettsia prowazekii. The cloned Cori supports autonomous plasmid replication selectively in the stalked cell type implying that replication of the entire chromosome also initiates between hemE and RP001. To confirm this location, we applied the 2-D (N/N) agarose gel electrophoresis technique to resolve and identify chromosome replication intermediates throughout a 30 kb region spanning Cori. Replication initiation in Cori was uniquely characterized by an 'origin bubble and Y-arc' pattern and this observation was supported by simple replication fork 'Y-arc' patterns that characterized the regions flanking Cori. These replication forks originated bi-directionally from within Cori as determined by the fork direction assay. Therefore, chromosomal replication initiates from the unusual hemE/RP001 intergenic region that we propose represents a new class of replication origins.

  5. Proteomic Analyses of the Shrimp White Spot Syndrome Virus

    Institute of Scientific and Technical Information of China (English)

    Yan-wei TAN; Zheng-li SHI

    2008-01-01

    White spot syndrome virus (WSSV), a unique member within the virus family Nimaviridae, is the most notorious aquatic virus infecting shrimp and other crustaceans and has caused enormous economic losses in the shrimp farming industry worldwide. Therefore, a comprehensive understanding of WSSV morphogenesis, structural proteins, and replication is essential for developing prevention measures of this serious parasite. The viral genome is approximately 300kb and contains more than 180 open reading frames (ORF). However, most of proteins encoded by these ORF have not been characterized. Due to the importance of WSSV structural proteins in the composition of the virion structure, infection process and interaction with host cells, knowledge of structural proteins is essential to understanding WSSV entry and infection as well as for exploring effective prevention measures. This review article summarizes mainly current investigations on WSSV structural proteins including the relative quantities, localization, function and protein-protein interactions. Traditional proteomic studies of 1D or 2D gel electrophoresis separations and mass spectrometry (MS) followed by database searches have identified a total of 39 structural proteins. Shotgun proteomics and iTRAQ were initiated to identify more structural proteins. To date, it is estimated that WSSV is assembled by at least 59 structural proteins, among them 35 are defined as the envelope fraction (including tegument proteins) and 9 as nucleocapsid proteins. Furthermore, the interaction within several major structural proteins has also been investigated. This identitification and characterization of WSSV protein components should help in the understanding of the viral assembly process and elucidate the roles of several major structural proteins.

  6. Formation of Anisotropic Block Copolymer Gels

    Science.gov (United States)

    Liaw, Chya Yan; Shull, Kenneth; Henderson, Kevin; Joester, Derk

    2011-03-01

    Anisotropic, fibrillar gels are important in a variety of processes. Biomineralization is one example, where the mineralization process often occurs within a matrix of collagen or chitin fibers that trap the mineral precursors and direct the mineralization process. We wish to replicate this type of behavior within block copolymer gels. Particularly, we are interested in employing gels composed of cylindrical micelles, which are anisotropic and closely mimic biological fibers. Micelle geometry is controlled in our system by manipulating the ratio of molecular weights of the two blocks and by controlling the detailed thermal processing history of the copolymer solutions. Small-Angle X-ray Scattering and Dynamic Light Scattering are used to determine the temperature dependence of the gel formation process. Initial experiments are based on a thermally-reversible alcohol-soluble system, that can be subsequently converted to a water soluble system by hydrolysis of a poly(t-butyl methacrylate) block to a poly (methacrylic acid) block. MRSEC.

  7. Analysis of Two-Dimensional Electrophoresis Gel Images

    DEFF Research Database (Denmark)

    Pedersen, Lars

    2002-01-01

    This thesis describes and proposes solutions to some of the currently most important problems in pattern recognition and image analysis of two-dimensional gel electrophoresis (2DGE) images. 2DGE is the leading technique to separate individual proteins in biological samples with many biological...... the methods developed in the literature specifically for matching protein spot patterns, the focus is on a method based on neighbourhood relations. These methods are applied to a range of 2DGE protein spot data in a comparative study. The point pattern matching requires segmentation of the gel images...... and since the correct image segmentation can be difficult, a new alternative approach, exploiting prior knowledge from a reference gel about the protein locations to segment an incoming gel image, is proposed....

  8. Stronger multilayer acrylic dielectric elastomer actuators with silicone gel coatings

    Science.gov (United States)

    Lau, Gih-Keong; La, Thanh-Giang; Sheng-Wei Foong, Ervin; Shrestha, Milan

    2016-12-01

    Multilayer dielectric elastomer actuators (DEA) perform worst off than single-layer DEAs due to higher susceptibility to electro-thermal breakdown. This paper presents a hot-spot model to predict the electro-thermal breakdown field of DEAs and its dependence on thermal insulation. To inhibit the electrothermal breakdown, silicone gel coating was applied as barrier coating to multilayer acrylic DEA. The gel coating helps suppress the electro-thermally induced puncturing of DEA membrane at the hot spot. As a result, the gel-coated DEAs, in either a single layer or a multilayer stack, can produce 30% more isometric stress change as compared to those none-coated. These gel-coated acrylic DEAs show great potential to make stronger artificial muscles.

  9. DNA replication and cancer

    DEFF Research Database (Denmark)

    Boyer, Anne-Sophie; Walter, David; Sørensen, Claus Storgaard

    2016-01-01

    A dividing cell has to duplicate its DNA precisely once during the cell cycle to preserve genome integrity avoiding the accumulation of genetic aberrations that promote diseases such as cancer. A large number of endogenous impacts can challenge DNA replication and cells harbor a battery of pathways...... causing DNA replication stress and genome instability. Further, we describe cellular and systemic responses to these insults with a focus on DNA replication restart pathways. Finally, we discuss the therapeutic potential of exploiting intrinsic replicative stress in cancer cells for targeted therapy....

  10. SpotADAPT

    DEFF Research Database (Denmark)

    Kaulakiene, Dalia; Thomsen, Christian; Pedersen, Torben Bach

    2015-01-01

    Having constantly increasing amounts of data, the analysis of it is often entrusted for a MapReduce framework. The execution of an analytical workload can be cheapened by adopting cloud computing resources, and in particular by using spot instances (cheap, fluctuating price instances) offered by ...

  11. Arc spot grouping: An entanglement of arc spot cells

    Energy Technology Data Exchange (ETDEWEB)

    Kajita, Shin, E-mail: kajita.shin@nagoya-u.jp [EcoTopia Science Institute, Nagoya University, Nagoya 464-8603 (Japan); Hwangbo, Dogyun; Ohno, Noriyasu [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); Tsventoukh, Mikhail M. [Lebedev Physical Institute, Russian Academy of Sciences, Moscow 119991 (Russian Federation); Barengolts, Sergey A. [Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow 119991 (Russian Federation)

    2014-12-21

    In recent experiments, clear transitions in velocity and trail width of an arc spot initiated on nanostructured tungsten were observed on the boundary of the thick and thin nanostructured layer regions. The velocity of arc spot was significantly decreased on the thick nanostructured region. It was suggested that the grouping decreased the velocity of arc spot. In this study, we try to explain the phenomena using a simple random walk model that has properties of directionality and self-avoidance. And grouping feature was added by installing an attractive force between spot cells with dealing with multi-spots. It was revealed that an entanglement of arc spot cells decreased the spot velocity, and spot cells tend to stamp at the same location many times.

  12. Impact of replicate types on proteomic expression analysis.

    Science.gov (United States)

    Karp, Natasha A; Spencer, Matthew; Lindsay, Helen; O'Dell, Kevin; Lilley, Kathryn S

    2005-01-01

    In expression proteomics, the samples utilized within an experimental design may include technical, biological, or pooled replicates. This manuscript discusses various experimental designs and the conclusions that can be drawn from them. Specifically, it addresses the impact of mixing replicate types on the statistical analysis which can be performed. This study focuses on difference gel electrophoresis (DiGE), but the issues are equally applicable to all quantitative methodologies assessing relative changes in protein expression.

  13. Diced electrophoresis gel assay for screening enzymes with specified activities.

    Science.gov (United States)

    Komatsu, Toru; Hanaoka, Kenjiro; Adibekian, Alexander; Yoshioka, Kentaro; Terai, Takuya; Ueno, Tasuku; Kawaguchi, Mitsuyasu; Cravatt, Benjamin F; Nagano, Tetsuo

    2013-04-24

    We have established the diced electrophoresis gel (DEG) assay as a proteome-wide screening tool to identify enzymes with activities of interest using turnover-based fluorescent substrates. The method utilizes the combination of native polyacrylamide gel electrophoresis (PAGE) with a multiwell-plate-based fluorometric assay to find protein spots with the specified activity. By developing fluorescent substrates that mimic the structure of neutrophil chemoattractants, we could identify enzymes involved in metabolic inactivation of the chemoattractants.

  14. Optimization of Large Gel 2D Electrophoresis for Proteomic Studies of Skeletal Muscle

    Science.gov (United States)

    Reed, Patrick W.; Densmore, Allison; Bloch, Robert J.

    2013-01-01

    We describe improved methods for large format, 2-dimensional gel electrophoresis (2-DE) that improve protein solubility and recovery, minimize proteolysis, and reduce the loss of resolution due to contaminants and manipulations of the gels, and thus enhance quantitative analysis of protein spots. Key modifications are: (i) the use of 7M urea + 2 M thiourea, instead of 9M urea, in sample preparation and in the tops of the gel tubes; (ii) standardized deionization of all solutions containing urea with a mixed bed ion exchange resin and removal of urea from the electrode solutions; and (iii) use of a new gel tank and cooling device that eliminate the need to run two separating gels in the SDS dimension. These changes make 2D-GE analysis more reproducible and sensitive, with minimal artifacts. Application of this method to the soluble fraction of muscle tissues reliably resolves ~1800 protein spots in adult human skeletal muscle and over 2800 spots in myotubes. PMID:22589104

  15. Replicating animal mitochondrial DNA

    Directory of Open Access Journals (Sweden)

    Emily A. McKinney

    2013-01-01

    Full Text Available The field of mitochondrial DNA (mtDNA replication has been experiencing incredible progress in recent years, and yet little is certain about the mechanism(s used by animal cells to replicate this plasmid-like genome. The long-standing strand-displacement model of mammalian mtDNA replication (for which single-stranded DNA intermediates are a hallmark has been intensively challenged by a new set of data, which suggests that replication proceeds via coupled leading-and lagging-strand synthesis (resembling bacterial genome replication and/or via long stretches of RNA intermediates laid on the mtDNA lagging-strand (the so called RITOLS. The set of proteins required for mtDNA replication is small and includes the catalytic and accessory subunits of DNA polymerase y, the mtDNA helicase Twinkle, the mitochondrial single-stranded DNA-binding protein, and the mitochondrial RNA polymerase (which most likely functions as the mtDNA primase. Mutations in the genes coding for the first three proteins are associated with human diseases and premature aging, justifying the research interest in the genetic, biochemical and structural properties of the mtDNA replication machinery. Here we summarize these properties and discuss the current models of mtDNA replication in animal cells.

  16. Poisson Spot with Magnetic Levitation

    Science.gov (United States)

    Hoover, Matthew; Everhart, Michael; D'Arruda, Jose

    2010-01-01

    In this paper we describe a unique method for obtaining the famous Poisson spot without adding obstacles to the light path, which could interfere with the effect. A Poisson spot is the interference effect from parallel rays of light diffracting around a solid spherical object, creating a bright spot in the center of the shadow.

  17. Great Red Spot (GRS)

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    A huge permanent anticyclone in Jupiter's southern hemisphere, visible as a reddish oval at just over 20 °S. The earliest unequivocal observation was by Heinrich Schwabe in 1831 (the often-quoted sighting by Robert Hooke in 1664 now seems to have been of a similar but different spot). The GRS became a striking feature around 1880, when it developed a deep red coloration. It was also prominent in ...

  18. Supramolecular Gel-Templated In Situ Synthesis and Assembly of CdS Quantum Dots Gels

    Science.gov (United States)

    Zhu, Lili; He, Jie; Wang, Xiaoliang; Li, Dawei; He, Haibing; Ren, Lianbing; Jiang, Biwang; Wang, Yong; Teng, Chao; Xue, Gi; Tao, Huchun

    2017-01-01

    Although many studies have attempted to develop strategies for spontaneously organizing nanoparticles (NPs) into three-dimensional (3D) geometries, it remains a fascinating challenge. In this study, a method for in situ synthesis and self-assembly of a CdS quantum dots (QDs) gel using a Cd supramolecular gel as a scaffold was demonstrated. During the QDs formation process, the Cd ions that constituted the Cd gels served as the precursors of the CdS QDs, and the oleic acid (OA) that ligated with the Cd in the supramolecular gels was capped on the surface of the CdS QDs in the form of carboxylate. The OA-stabilized CdS QDs were in situ synthesized in the entangled self-assembled fibrillar networks (SAFIN) of the Cd gels through reactions between the gelator and H2S. As a result, the QDs exactly replicated the framework of the SAFIN in the CdS QD gels instead of simply assembling along the SAFIN of the supramolecular gels. Moreover, the CdS QDs showed extraordinary sensitivity in the fluorescence detection of IO4 - anions. The facile one-step method developed here is a new approach to assembling nanostructured materials into 3D architectures and has general implications for the design of low molecular mass gelators to bring desired functionality to the developed supramolecular gels.

  19. El spot electoral negativo

    Directory of Open Access Journals (Sweden)

    Palma Peña-Jiménez

    2011-01-01

    Full Text Available l spot político tiene durante la campaña un objetivo final inequívoco: la consecución del voto favorable. Se dirige al cuerpo electoral a través de la televisión y de Internet, y presenta, en muchos casos, un planteamiento negativo, albergando mensajes destinados a la crítica frontal contra el adversario, más que a la exposición de propuestas propias. Este artículo se centra en el análisis del spot electoral negativo, en aquellas producciones audiovisuales construidas sin más causa que la reprobación del contrincante. Se trata de vídeos que, lejos de emplearse en difundir las potencialidades de la organización y las virtudes de su candidato –además de su programa electoral–, consumen su tiempo en descalificar al oponente mediante la transmisión de mensajes, muchas veces, ad hominem. Repasamos el planteamiento negativo del spot electoral desde su primera manifestación, que en España data de 1996, año de emisión del conocido como vídeo del dóberman, sin olvidar otros ejemplos que completan el objeto de estudio.

  20. Spot- Zombie Filtering System

    Directory of Open Access Journals (Sweden)

    Arathy Rajagopal

    2014-01-01

    Full Text Available A major security challenge on the Internet is the existence of the large number of compromised machines. Such machines have been increasingly used to launch various security attacks including spamming and spreading malware, DDoS, and identity theft. These compromised machines are called “Zombies”. In general E-mail applications and providers uses spam filters to filter the spam messages. Spam filtering is a technique for discriminating the genuine message from the spam messages. The attackers send the spam messages to the targeted machine by exalting the filters, which causes the increase in false positives and false negatives. We develop an effective spam zombie detection system named SPOT by monitoring outgoing messages of a network. SPOT focuses on the number of outgoing messages that are originated or forwarded by each computer on a network to identify the presence of Zombies. SPOT is designed based on a powerful statistical tool called Sequential Probability Ratio Test, which has bounded false positive and false negative error rates.

  1. Spot- Zombie Filtering System

    Directory of Open Access Journals (Sweden)

    Arathy Rajagopal

    2015-10-01

    Full Text Available A major security challenge on the Internet is the existence of the large number of compromised machines. Such machines have been increasingly used to launch various security attacks including spamming and spreading malware, DDoS, and identity theft. These compromised machines are called "Zombies". In general E-mail applications and providers uses spam filters to filter the spam messages. Spam filtering is a technique for discriminating the genuine message from the spam messages. The attackers send the spam messages to the targeted machine by exalting the filters, which causes the increase in false positives and false negatives. We develop an effective spam zombie detection system named SPOT by monitoring outgoing messages of a network. SPOT focuses on the number of outgoing messages that are originated or forwarded by each computer on a network to identify the presence of Zombies. SPOT is designed based on a powerful statistical tool called Sequential Probability Ratio Test, which has bounded false positive and false negative error rates.

  2. The Replication Recipe: What makes for a convincing replication?

    NARCIS (Netherlands)

    Brandt, M.J.; IJzerman, H.; Dijksterhuis, A.J.; Farach, F.J.; Geller, J.; Giner-Sorolla, R.; Grange, J.A.; Perugini, M.; Spies, J.R.; Veer, A. van 't

    2014-01-01

    Psychological scientists have recently started to reconsider the importance of close replications in building a cumulative knowledge base; however, there is no consensus about what constitutes a convincing close replication study. To facilitate convincing close replication attempts we have developed

  3. Hot-spot application of biocontrol agents to replace pesticides in large scale commercial rose farms in Kenya

    DEFF Research Database (Denmark)

    Gacheri, Catherine; Kigen, Thomas; Sigsgaard, Lene

    2015-01-01

    Rose (Rosa hybrida L.) is the most important ornamental crop in Kenya, with huge investments in pest management. We provide the first full-scale, replicated experiment comparing cost and yield of conventional two-spotted spider mite (Tetranychus urticae Koch) control with hot-spot applications of....... persimilis hot-spot treatments in commercial cut rose production, effectively reducing pest management costs with no loss in crop yield.......Rose (Rosa hybrida L.) is the most important ornamental crop in Kenya, with huge investments in pest management. We provide the first full-scale, replicated experiment comparing cost and yield of conventional two-spotted spider mite (Tetranychus urticae Koch) control with hot-spot applications...... of the predatory mite Phytoseiulus persimilis (Acari: Phytoseidae) in large commercial rose greenhouses. Hot-spot treatments replaced acaricides except at high infestations and the two treatments were applied in seven greenhouses each. With the conventional treatment, acaricides were applied when T. urticae...

  4. Cognitive sophistication does not attenuate the bias blind spot.

    Science.gov (United States)

    West, Richard F; Meserve, Russell J; Stanovich, Keith E

    2012-09-01

    The so-called bias blind spot arises when people report that thinking biases are more prevalent in others than in themselves. Bias turns out to be relatively easy to recognize in the behaviors of others, but often difficult to detect in one's own judgments. Most previous research on the bias blind spot has focused on bias in the social domain. In 2 studies, we found replicable bias blind spots with respect to many of the classic cognitive biases studied in the heuristics and biases literature (e.g., Tversky & Kahneman, 1974). Further, we found that none of these bias blind spots were attenuated by measures of cognitive sophistication such as cognitive ability or thinking dispositions related to bias. If anything, a larger bias blind spot was associated with higher cognitive ability. Additional analyses indicated that being free of the bias blind spot does not help a person avoid the actual classic cognitive biases. We discuss these findings in terms of a generic dual-process theory of cognition.

  5. Testosterone Nasal Gel

    Science.gov (United States)

    Testosterone nasal gel is used to treat symptoms of low testosterone in men who have hypogonadism (a condition in which the ... does not produce enough natural testosterone). Testosterone nasal gel is used only for men with low testosterone ...

  6. Modeling DNA Replication.

    Science.gov (United States)

    Bennett, Joan

    1998-01-01

    Recommends the use of a model of DNA made out of Velcro to help students visualize the steps of DNA replication. Includes a materials list, construction directions, and details of the demonstration using the model parts. (DDR)

  7. Eukaryotic DNA Replication Fork.

    Science.gov (United States)

    Burgers, Peter M J; Kunkel, Thomas A

    2017-06-20

    This review focuses on the biogenesis and composition of the eukaryotic DNA replication fork, with an emphasis on the enzymes that synthesize DNA and repair discontinuities on the lagging strand of the replication fork. Physical and genetic methodologies aimed at understanding these processes are discussed. The preponderance of evidence supports a model in which DNA polymerase ε (Pol ε) carries out the bulk of leading strand DNA synthesis at an undisturbed replication fork. DNA polymerases α and δ carry out the initiation of Okazaki fragment synthesis and its elongation and maturation, respectively. This review also discusses alternative proposals, including cellular processes during which alternative forks may be utilized, and new biochemical studies with purified proteins that are aimed at reconstituting leading and lagging strand DNA synthesis separately and as an integrated replication fork.

  8. [White spot lesions and orthodontic treatment. Prevention and treatment].

    Science.gov (United States)

    Morrier, Jean-Jacques

    2014-09-01

    Decalcification of the enamel surface adjacent to fixed orthodontic appliances, in the form of white spot lesions, is a common and frequent well-known side-effect of orthodontic treatment. Fixed appliances and the bonding materials increase the retention of biofilm and encourage the formation of white spot lesions. Management of these lesions begins with a good oral hygiene regime and needs to be associated with use of fluoride agents (fluoridated toothpaste, fluoride containing mouth rinse, gel, varnish, bonding materials, elastic ligature), CPP-ACP, antiseptics, LASER, tooth whitening, resin infiltration, micro-abrasion. The purpose of this review is to access the direct evidence regarding the prevention and management of white spot lesions during and after orthodontic treatment.

  9. Abiotic self-replication.

    Science.gov (United States)

    Meyer, Adam J; Ellefson, Jared W; Ellington, Andrew D

    2012-12-18

    The key to the origins of life is the replication of information. Linear polymers such as nucleic acids that both carry information and can be replicated are currently what we consider to be the basis of living systems. However, these two properties are not necessarily coupled. The ability to mutate in a discrete or quantized way, without frequent reversion, may be an additional requirement for Darwinian evolution, in which case the notion that Darwinian evolution defines life may be less of a tautology than previously thought. In this Account, we examine a variety of in vitro systems of increasing complexity, from simple chemical replicators up to complex systems based on in vitro transcription and translation. Comparing and contrasting these systems provides an interesting window onto the molecular origins of life. For nucleic acids, the story likely begins with simple chemical replication, perhaps of the form A + B → T, in which T serves as a template for the joining of A and B. Molecular variants capable of faster replication would come to dominate a population, and the development of cycles in which templates could foster one another's replication would have led to increasingly complex replicators and from thence to the initial genomes. The initial genomes may have been propagated by RNA replicases, ribozymes capable of joining oligonucleotides and eventually polymerizing mononucleotide substrates. As ribozymes were added to the genome to fill gaps in the chemistry necessary for replication, the backbone of a putative RNA world would have emerged. It is likely that such replicators would have been plagued by molecular parasites, which would have been passively replicated by the RNA world machinery without contributing to it. These molecular parasites would have been a major driver for the development of compartmentalization/cellularization, as more robust compartments could have outcompeted parasite-ridden compartments. The eventual outsourcing of metabolic

  10. Adenovirus DNA Replication

    OpenAIRE

    Hoeben, Rob C.; Uil, Taco G.

    2013-01-01

    Adenoviruses have attracted much attention as probes to study biological processes such as DNA replication, transcription, splicing, and cellular transformation. More recently these viruses have been used as gene-transfer vectors and oncolytic agents. On the other hand, adenoviruses are notorious pathogens in people with compromised immune functions. This article will briefly summarize the basic replication strategy of adenoviruses and the key proteins involved and will deal with the new deve...

  11. Hot-spot application of biocontrol agents to replace pesticides in large scale commercial rose farms in Kenya

    DEFF Research Database (Denmark)

    Gacheri, Catherine; Kigen, Thomas; Sigsgaard, Lene

    2015-01-01

    Rose (Rosa hybrida L.) is the most important ornamental crop in Kenya, with huge investments in pest management. We provide the first full-scale, replicated experiment comparing cost and yield of conventional two-spotted spider mite (Tetranychus urticae Koch) control with hot-spot applications....... persimilis hot-spot treatments in commercial cut rose production, effectively reducing pest management costs with no loss in crop yield....

  12. Extracting information from two-dimensional electrophoresis gels by partial least squares regression

    DEFF Research Database (Denmark)

    Jessen, Flemming; Lametsch, R.; Bendixen, E.;

    2002-01-01

    of all proteins/spots in the gels. In the present study it is demonstrated how information can be extracted by multivariate data analysis. The strategy is based on partial least squares regression followed by variable selection to find proteins that individually or in combination with other proteins vary......Two-dimensional gel electrophoresis (2-DE) produces large amounts of data and extraction of relevant information from these data demands a cautious and time consuming process of spot pattern matching between gels. The classical approach of data analysis is to detect protein markers that appear...

  13. Minichromosome replication in vitro: inhibition of re-replication by replicatively assembled nucleosomes.

    Science.gov (United States)

    Krude, T; Knippers, R

    1994-08-19

    Single-stranded circular DNA, containing the SV40 origin sequence, was used as a template for complementary DNA strand synthesis in cytosolic extracts from HeLa cells. In the presence of the replication-dependent chromatin assembly factor CAF-1, defined numbers of nucleosomes were assembled during complementary DNA strand synthesis. These minichromosomes were then induced to semiconservatively replicate by the addition of the SV40 initiator protein T antigen (re-replication). The results indicate that re-replication of minichromosomes appears to be inhibited by two independent mechanisms. One acts at the initiation of minichromosome re-replication, and the other affects replicative chain elongation. To directly demonstrate the inhibitory effect of replicatively assembled nucleosomes, two types of minichromosomes were prepared: (i) post-replicative minichromosomes were assembled in a reaction coupled to replication as above; (ii) pre-replicative minichromosomes were assembled independently of replication on double-stranded DNA. Both types of minichromosomes were used as templates for DNA replication under identical conditions. Replicative fork movement was found to be impeded only on post-replicative minichromosome templates. In contrast, pre-replicative minichromosomes allowed one unconstrained replication cycle, but re-replication was inhibited due to a block in fork movement. Thus, replicatively assembled chromatin may have a profound influence on the re-replication of DNA.

  14. Turbulent spots in hypervelocity flow

    Science.gov (United States)

    Jewell, Joseph S.; Leyva, Ivett A.; Shepherd, Joseph E.

    2017-04-01

    The turbulent spot propagation process in boundary layer flows of air, nitrogen, carbon dioxide, and air/carbon dioxide mixtures in thermochemical nonequilibrium at high enthalpy is investigated. Experiments are performed in a hypervelocity reflected shock tunnel with a 5-degree half-angle axisymmetric cone instrumented with flush-mounted fast-response coaxial thermocouples. Time-resolved and spatially demarcated heat transfer traces are used to track the propagation of turbulent bursts within the mean flow, and convection rates at approximately 91, 74, and 63% of the boundary layer edge velocity, respectively, are observed for the leading edge, peak, and trailing edge of the spots. A simple model constructed with these spot propagation parameters is used to infer spot generation rates from observed transition onset to completion distance. Spot generation rates in air and nitrogen are estimated to be approximately twice the spot generation rates in air/carbon dioxide mixtures.

  15. Investigating variation in replicability: A "Many Labs" replication project

    NARCIS (Netherlands)

    Klein, R.A.; Ratliff, K.A.; Vianello, M.; Adams, R.B.; Bahnik, S.; Bernstein, M.J.; Bocian, K.; Brandt, M.J.; Brooks, B.; Brumbaugh, C.C.; Cemalcilar, Z.; Chandler, J.; Cheong, W.; Davis, W.E.; Devos, T.; Eisner, M.; Frankowska, N.; Furrow, D.; Galliani, E.M.; Hasselman, F.W.; Hicks, J.A.; Hovermale, J.F.; Hunt, S.J.; Huntsinger, J.R.; IJzerman, H.; John, M.S.; Joy-Gaba, J.A.; Kappes, H.B.; Krueger, L.E.; Kurtz, J.; Levitan, C.A.; Mallett, R.K.; Morris, W.L.; Nelson, A.J.; Nier, J.A.; Packard, G.; Pilati, R.; Rutchick, A.M.; Schmidt, K.; Skorinko, J.L.M.; Smith, R.; Steiner, T.G.; Storbeck, J.; Van Swol, L.M.; Thompson, D.; Veer, A.E. van 't; Vaughn, L.A.; Vranka, M.; Wichman, A.L.; Woodzicka, J.A.; Nosek, B.A.

    2014-01-01

    Although replication is a central tenet of science, direct replications are rare in psychology. This research tested variation in the replicability of 13 classic and contemporary effects across 36 independent samples totaling 6,344 participants. In the aggregate, 10 effects replicated consistently.

  16. Hepatitis B virus replication

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Hepadnaviruses, including human hepatitis B virus (HBV), replicate through reverse transcription of an RNA intermediate, the pregenomic RNA (pgRNA). Despite this kinship to retroviruses, there are fundamental differences beyond the fact that hepadnavirions contain DNA instead of RNA. Most peculiar is the initiation of reverse transcription: it occurs by protein-priming, is strictly committed to using an RNA hairpin on the pgRNA,ε, as template, and depends on cellular chaperones;moreover, proper replication can apparently occur only in the specialized environment of intact nucleocapsids.This complexity has hampered an in-depth mechanistic understanding. The recent successful reconstitution in the test tube of active replication initiation complexes from purified components, for duck HBV (DHBV),now allows for the analysis of the biochemistry of hepadnaviral replication at the molecular level. Here we review the current state of knowledge at all steps of the hepadnaviral genome replication cycle, with emphasis on new insights that turned up by the use of such cellfree systems. At this time, they can, unfortunately,not be complemented by three-dimensional structural information on the involved components. However, at least for the s RNA element such information is emerging,raising expectations that combining biophysics with biochemistry and genetics will soon provide a powerful integrated approach for solving the many outstanding questions. The ultimate, though most challenging goal,will be to visualize the hepadnaviral reverse transcriptase in the act of synthesizing DNA, which will also have strong implications for drug development.

  17. Transport Phenomena in Gel

    Directory of Open Access Journals (Sweden)

    Masayuki Tokita

    2016-05-01

    Full Text Available Gel becomes an important class of soft materials since it can be seen in a wide variety of the chemical and the biological systems. The unique properties of gel arise from the structure, namely, the three-dimensional polymer network that is swollen by a huge amount of solvent. Despite the small volume fraction of the polymer network, which is usually only a few percent or less, gel shows the typical properties that belong to solids such as the elasticity. Gel is, therefore, regarded as a dilute solid because its elasticity is much smaller than that of typical solids. Because of the diluted structure, small molecules can pass along the open space of the polymer network. In addition to the viscous resistance of gel fluid, however, the substance experiences resistance due to the polymer network of gel during the transport process. It is, therefore, of importance to study the diffusion of the small molecules in gel as well as the flow of gel fluid itself through the polymer network of gel. It may be natural to assume that the effects of the resistance due to the polymer network of gel depends strongly on the network structure. Therefore, detailed study on the transport processes in and through gel may open a new insight into the relationship between the structure and the transport properties of gel. The two typical transport processes in and through gel, that is, the diffusion of small molecules due to the thermal fluctuations and the flow of gel fluid that is caused by the mechanical pressure gradient will be reviewed.

  18. Spotting effect in microarray experiments

    Directory of Open Access Journals (Sweden)

    Mary-Huard Tristan

    2004-05-01

    Full Text Available Abstract Background Microarray data must be normalized because they suffer from multiple biases. We have identified a source of spatial experimental variability that significantly affects data obtained with Cy3/Cy5 spotted glass arrays. It yields a periodic pattern altering both signal (Cy3/Cy5 ratio and intensity across the array. Results Using the variogram, a geostatistical tool, we characterized the observed variability, called here the spotting effect because it most probably arises during steps in the array printing procedure. Conclusions The spotting effect is not appropriately corrected by current normalization methods, even by those addressing spatial variability. Importantly, the spotting effect may alter differential and clustering analysis.

  19. Psychology, replication & beyond.

    Science.gov (United States)

    Laws, Keith R

    2016-06-01

    Modern psychology is apparently in crisis and the prevailing view is that this partly reflects an inability to replicate past findings. If a crisis does exists, then it is some kind of 'chronic' crisis, as psychologists have been censuring themselves over replicability for decades. While the debate in psychology is not new, the lack of progress across the decades is disappointing. Recently though, we have seen a veritable surfeit of debate alongside multiple orchestrated and well-publicised replication initiatives. The spotlight is being shone on certain areas and although not everyone agrees on how we should interpret the outcomes, the debate is happening and impassioned. The issue of reproducibility occupies a central place in our whig history of psychology.

  20. Severity of banana leaf spot in an intercropping system in two cycles of banana Prata Ana

    OpenAIRE

    Valdeir Dias Gonçalves; Silvia Nietsche; Marlon Cristian Toledo Pereira; Manoel Xavier de Oliveira Júnior; Roberto Célio Antunes Júnior; Carlos Ruggiero

    2008-01-01

    Prata Ana is the most planted banana cultivar in northern Minas Gerais, Brazil. It is however susceptible to several pathogens. This study was carried out to evaluate the disease severity of banana leaf spot in the Prata Ana cv. in the first and second cycle under six different planting systems. The randomized block experimental design was used with six treatments and four replications. lit an evaluation of the severity of banana leaf spot, no disease symptoms were found on Thap Maeo and Caip...

  1. Sol-Gel Glasses

    Science.gov (United States)

    Mukherjee, S. P.

    1985-01-01

    Multicomponent homogeneous, ultrapure noncrystalline gels/gel derived glasses are promising batch materials for the containerless glass melting experiments in microgravity. Hence, ultrapure, homogeneous gel precursors could be used to: (1) investigate the effect of the container induced nucleation on the glass forming ability of marginally glass forming compositions; and (2) investigate the influence of gravity on the phase separation and coarsening behavior of gel derived glasses in the liquid-liquid immiscibility zone of the nonsilicate systems having a high density phase. The structure and crystallization behavior of gels in the SiO2-GeO2 as a function of gel chemistry and thermal treatment were investigated. As are the chemical principles involved in the distribution of a second network former in silica gel matrix being investigated. The procedures for synthesizing noncrystalline gels/gel-monoliths in the SiO2-GeO2, GeO2-PbO systems were developed. Preliminary investigations on the levitation and thermal treatment of germania silicate gel-monoliths in the Pressure Facility Acoustic Levitator were done.

  2. The SPOT satellite

    Science.gov (United States)

    Fouquet, J.-P.

    1981-03-01

    The background, objectives and data products of the French SPOT remote sensing satellite system are presented. The system, which was developed starting in 1978 with the subsequent participation of Sweden and Belgium, is based on a standard multimission platform with associated ground control station and a mission-specific payload, which includes two High-Resolution Visible range instruments allowing the acquisition of stereoscopic views from different orbits. Mission objectives include the definition of future remote sensing systems, the compilation of a cartographic and resources data base, the study of species discrimination and production forecasting based on frequent access and off-nadir viewing, the compilation of a stereoscopic data base, and platform and instrument qualification, for possible applications in cartography, geology and agriculture. Standard data products will be available at three levels of preprocessing: radiometric correction only, precision processing for vertical viewing, and cartographic quality processing.

  3. In vitro replication of cyanobacterial plasmids from Synechocystis PCC 6803.

    Science.gov (United States)

    Yang, X; Daniell, H; McFadden, B

    1994-09-01

    Little knowledge of DNA replication in cyanobacteria is available. In this study, we report the development and characterization of an in vitro system for studies of replication of the endogenous plasmids from the unicellular cyanobacterium Synechocystis 6803. This system (fraction III) was isolated at high salt concentrations and partially purified on a heparin-agarose column. DNA polymerases in Synechocystis 6803 appeared to be associated with membranes and could be released by the addition of ammonium sulfate to 20% saturation. DNA synthesis in fraction III was dependent on the addition of cyanobacterial plasmids isolated from the same strain. The in vitro replication products consist mostly of the supercoiled form of the plasmids. Unlike replication of many Escherichia coli plasmids, replication of cyanobacterial plasmids did not require added ATP, was not inhibited by omission of the ribonucleotides, and was insensitive to the RNA polymerase inhibitor rifampicin and the gyrase inhibitor novobiocin, but was inhibited by ethidium bromide. These data suggest that RNA may not be involved in the initiation of replication of cyanobacterial plasmids from Synechocystis 6803. In addition, intermediates of replication have been detected by two-dimensional gel electrophoresis. Density labeling experiments also indicate that cyanobacterial plasmid synthesis in vitro occurs by a semiconservative replication.

  4. The inter- and intra-operator variability in manual spot segmentation and its effect on spot quantitation in two-dimensional electrophoresis analysis.

    Science.gov (United States)

    Millioni, Renato; Sbrignadello, Stefano; Tura, Andrea; Iori, Elisabetta; Murphy, Ellen; Tessari, Paolo

    2010-05-01

    Separation of complex mixtures of proteins by 2-DE is a fundamental component of current proteomic technology. Quantitative analysis of the images generated by digitization of such gels is critical for identifying alterations in protein expression within a given biological system. Software packages are designed for this purpose. The accurate definition of protein spot boundaries, using a suitable method of image segmentation, is a key requirement for image analysis. It is often necessary for operators to intervene manually to correct mistakes in spot segmentation; therefore operator subjectivity and differences in ability can weaken the analysis. We estimated the error in spot quantification after manual spot segmentation, which was performed by different operators, using two different software packages. Our results clearly show that this operation was associated with significant inter- and intra-variability and an overestimation of subsequent spot intensity, especially when spots were weak. For comparative studies, we suggest separately analysing spots which have been manually segmented by imposing a requirement for at least a threefold difference in spot intensity in addition to use of statistical tests.

  5. DNA replication origins in archaea

    OpenAIRE

    Zhenfang eWu; Jingfang eLiu; Haibo eYang; Hua eXiang

    2014-01-01

    DNA replication initiation, which starts at specific chromosomal site (known as replication origins), is the key regulatory stage of chromosome replication. Archaea, the third domain of life, use a single or multiple origin(s) to initiate replication of their circular chromosomes. The basic structure of replication origins is conserved among archaea, typically including an AT-rich unwinding region flanked by several conserved repeats (origin recognition box, ORB) that are located adjacent to ...

  6. Justifications Shape Ethical Blind Spots

    NARCIS (Netherlands)

    Pittarello, Andrea; Leib, Margarita; Gordon-Hecker, Tom; Shalvi, Shaul

    2015-01-01

    To some extent, unethical behavior results from people's limited attention to ethical considerations, which results in an ethical blind spot. Here, we focus on the role of ambiguity in shaping people's ethical blind spots, which in turn lead to their ethical failures. We suggest that in ambiguous se

  7. Divide and conquer spot noise

    NARCIS (Netherlands)

    Leeuw, W.C. de; Liere, R. van

    1997-01-01

    The design and implementation of an interactive spot noise algorithm is presented. Spot noise is a technique which utilizes texture for the visualization of flow fields. Various design tradeoffs are discussed that allow an optimal implementation on a range of high end graphical workstations. Two app

  8. Black-spot poison ivy.

    Science.gov (United States)

    Schram, Sarah E; Willey, Andrea; Lee, Peter K; Bohjanen, Kimberly A; Warshaw, Erin M

    2008-01-01

    In black-spot poison ivy dermatitis, a black lacquerlike substance forms on the skin when poison ivy resin is exposed to air. Although the Toxicodendron group of plants is estimated to be the most common cause of allergic contact dermatitis in the United States, black-spot poison ivy dermatitis is relatively rare.

  9. Replication studies in longevity

    DEFF Research Database (Denmark)

    Varcasia, O; Garasto, S; Rizza, T

    2001-01-01

    In Danes we replicated the 3'APOB-VNTR gene/longevity association study previously carried out in Italians, by which the Small alleles (less than 35 repeats) had been identified as frailty alleles for longevity. In Danes, neither genotype nor allele frequencies differed between centenarians and 20...

  10. Replication-Fork Dynamics

    NARCIS (Netherlands)

    Duderstadt, Karl E.; Reyes-Lamothe, Rodrigo; van Oijen, Antoine M.; Sherratt, David J.

    2014-01-01

    The proliferation of all organisms depends on the coordination of enzymatic events within large multiprotein replisomes that duplicate chromosomes. Whereas the structure and function of many core replisome components have been clarified, the timing and order of molecular events during replication re

  11. Coronavirus Attachment and Replication

    Science.gov (United States)

    1988-03-28

    synthesis during RNA replication of vesicular stomatitis virus. J. Virol. 49:303-309. Pedersen, N.C. 1976a. Feline infectious peritonitis: Something old...receptors on intestinal brush border membranes from normal host species were developed for canine (CCV), feline (FIPV), porcine (TGEV), human (HCV...gastroenteritis receptor on pig BBMs ...... ................. ... 114 Feline infectious peritonitis virus receptor on cat BBMs ... .............. 117 Human

  12. Optimizing Human Bile Preparation for Two-Dimensional Gel Electrophoresis

    Directory of Open Access Journals (Sweden)

    Hao-Tsai Cheng

    2016-01-01

    Full Text Available Aims. Bile is an important body fluid which assists in the digestion of fat and excretion of endogenous and exogenous compounds. In the present study, an improved sample preparation for human bile was established. Methods and Material. The method involved acetone precipitation followed by protein extraction using commercially available 2D Clean-Up kit. The effectiveness was evaluated by 2-dimensional electrophoresis (2DE profiling quality, including number of protein spots and spot distribution. Results. The total protein of bile fluid in benign biliary disorders was 0.797 ± 0.465 μg/μL. The sample preparation method using acetone precipitation first followed by 2D Clean-Up kit protein extraction resulted in better quality of 2DE gel images in terms of resolution as compared with other sample preparation methods. Using this protocol, we obtained approximately 558 protein spots on the gel images and with better protein spots presentation of haptoglobin, serum albumin, serotransferrin, and transthyretin. Conclusions. Protein samples of bile prepared using acetone precipitation followed by 2D Clean-Up kit exhibited high protein resolution and significant protein profile. This optimized protein preparation protocol can effectively concentrate bile proteins, remove abundant proteins and debris, and yield clear presentation of nonabundant proteins and its isoforms on 2-dimensional electrophoresis gel images.

  13. Pulse Field Gel Electrophoresis.

    Science.gov (United States)

    Sharma-Kuinkel, Batu K; Rude, Thomas H; Fowler, Vance G

    2016-01-01

    Pulse Field Gel Electrophoresis (PFGE) is a powerful genotyping technique used for the separation of large DNA molecules (entire genomic DNA) after digesting it with unique restriction enzymes and applying to a gel matrix under the electric field that periodically changes direction. PFGE is a variation of agarose gel electrophoresis that permits analysis of bacterial DNA fragments over an order of magnitude larger than that with conventional restriction enzyme analysis. It provides a good representation of the entire bacterial chromosome in a single gel with a highly reproducible restriction profile, providing clearly distinct and well-resolved DNA fragments.

  14. CONFORMANCE IMPROVEMENT USING GELS

    Energy Technology Data Exchange (ETDEWEB)

    Randall S. Seright

    2003-09-01

    This report describes work performed during the second year of the project, ''Conformance Improvement Using Gels.'' The project has two objectives. The first objective is to identify gel compositions and conditions that substantially reduce flow through fractures that allow direct channeling between wells, while leaving secondary fractures open so that high fluid injection and production rates can be maintained. The second objective is to optimize treatments in fractured production wells, where the gel must reduce permeability to water much more than that to oil. Pore-level images from X-ray computed microtomography were re-examined for Berea sandstone and porous polyethylene. This analysis suggests that oil penetration through gel-filled pores occurs by a gel-dehydration mechanism, rather than a gel-ripping mechanism. This finding helps to explain why aqueous gels can reduce permeability to water more than to oil. We analyzed a Cr(III)-acetate-HPAM gel treatment in a production well in the Arbuckle formation. The availability of accurate pressure data before, during, and after the treatment was critical for the analysis. After the gel treatment, water productivity was fairly constant at about 20% of the pre-treatment value. However, oil productivity was stimulated by a factor of 18 immediately after the treatment. During the six months after the treatment, oil productivity gradually decreased to approach the pre-treatment value. To explain this behavior, we proposed that the fracture area open to oil flow was increased substantially by the gel treatment, followed by a gradual closing of the fractures during subsequent production. For a conventional Cr(III)-acetate-HPAM gel, the delay between gelant preparation and injection into a fracture impacts the placement, leakoff, and permeability reduction behavior. Formulations placed as partially formed gels showed relatively low pressure gradients during placement, and yet substantially reduced the

  15. Reversible Switching of Cooperating Replicators

    Science.gov (United States)

    Urtel, Georg C.; Rind, Thomas; Braun, Dieter

    2017-02-01

    How can molecules with short lifetimes preserve their information over millions of years? For evolution to occur, information-carrying molecules have to replicate before they degrade. Our experiments reveal a robust, reversible cooperation mechanism in oligonucleotide replication. Two inherently slow replicating hairpin molecules can transfer their information to fast crossbreed replicators that outgrow the hairpins. The reverse is also possible. When one replication initiation site is missing, single hairpins reemerge from the crossbreed. With this mechanism, interacting replicators can switch between the hairpin and crossbreed mode, revealing a flexible adaptation to different boundary conditions.

  16. Spot Welding of Honeycomb Structures

    Science.gov (United States)

    Cohal, V.

    2017-08-01

    Honeycomb structures are used to prepare meals water jet cutting machines for textile. These honeycomb structures are made of stainless steel sheet thickness of 0.1-0.2 mm. Corrugated sheet metal strips are between two gears with special tooth profile. Hexagonal cells for obtaining these strips are welded points between them. Spot welding device is three electrodes in the upper part, which carries three welding points across the width of the strip of corrugated sheet metal. Spot welding device filled with press and advance mechanisms. The paper presents the values of the regime for spot welding.

  17. GelTouch

    DEFF Research Database (Denmark)

    Miruchna, Viktor; Walter, Robert; Lindlbauer, David

    2015-01-01

    We present GelTouch, a gel-based layer that can selectively transition between soft and stiff to provide tactile multi-touch feedback. It is flexible, transparent when not activated, and contains no mechanical, electromagnetic, or hydraulic components, resulting in a compact form factor (a 2mm thin...... touchscreen layer for our prototype). The activated areas can be morphed freely and continuously, without being limited to fixed, predefined shapes. GelTouch consists of a poly(N-isopropylacrylamide) gel layer which alters its viscoelasticity when activated by applying heat (>32 C). We present three different...... a tablet with 6x4 tactile areas, enabling a tactile numpad, slider, and thumbstick. We show that the gel is up to 25 times stiffer when activated and that users detect tactile features reliably (94.8%)....

  18. The latest advancements in proteomic two-dimensional gel electrophoresis analysis applied to biological samples.

    Science.gov (United States)

    Santucci, Laura; Bruschi, Maurizio; Ghiggeri, Gian Marco; Candiano, Giovanni

    2015-01-01

    Two-dimensional gel electrophoresis (2DE) is one of the fundamental approaches in proteomics for the separation and visualization of complex protein mixtures. Proteins can be analyzed by 2DE using isoelectric focusing (IEF) in the first dimension, combined to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the second dimension, gel staining (silver and Coomassie), image analysis, and 2DE gel database. High-resolution 2DE can resolve up to 5,000 different proteins simultaneously (∼2,000 proteins routinely), and detect and quantify <1 ng of protein per spot. Here, we describe the latest developments for a more complete analysis of biological fluids.

  19. Chromatin replication and epigenome maintenance

    DEFF Research Database (Denmark)

    Alabert, Constance; Groth, Anja

    2012-01-01

    initiates, whereas the replication process itself disrupts chromatin and challenges established patterns of genome regulation. Specialized replication-coupled mechanisms assemble new DNA into chromatin, but epigenome maintenance is a continuous process taking place throughout the cell cycle. If DNA...

  20. Chromatin replication and epigenome maintenance

    DEFF Research Database (Denmark)

    Alabert, Constance; Groth, Anja

    2012-01-01

    initiates, whereas the replication process itself disrupts chromatin and challenges established patterns of genome regulation. Specialized replication-coupled mechanisms assemble new DNA into chromatin, but epigenome maintenance is a continuous process taking place throughout the cell cycle. If DNA...

  1. Coulomb explosion of "hot spot"

    CERN Document Server

    Oreshkin, V I; Chaikovsky, S A; Artyomov, A P

    2016-01-01

    The study presented in this paper has shown that the generation of hard x rays and high-energy ions, which are detected in pinch implosion experiments, may be associated with the Coulomb explosion of the hot spot that is formed due to the outflow of the material from the pinch cross point. During the process of material outflow, the temperature of the hot spot plasma increases, and conditions arise for the plasma electrons to become continuously accelerated. The runaway of electrons from the hot spot region results in the buildup of positive space charge in this region followed by a Coulomb explosion. The conditions for the hot spot plasma electrons to become continuously accelerated have been revealed and estimates have been obtained for the kinetic energy of the ions generated by the Coulomb explosion.

  2. Initiation of adenovirus DNA replication.

    OpenAIRE

    Reiter, T; Fütterer, J; Weingärtner, B; Winnacker, E L

    1980-01-01

    In an attempt to study the mechanism of initiation of adenovirus DNA replication, an assay was developed to investigate the pattern of DNA synthesis in early replicative intermediates of adenovirus DNA. By using wild-type virus-infected cells, it was possible to place the origin of adenovirus type 2 DNA replication within the terminal 350 to 500 base pairs from either of the two molecular termini. In addition, a variety of parameters characteristic of adenovirus DNA replication were compared ...

  3. Chromatin replication and epigenome maintenance

    DEFF Research Database (Denmark)

    Alabert, Constance; Groth, Anja

    2012-01-01

    Stability and function of eukaryotic genomes are closely linked to chromatin structure and organization. During cell division the entire genome must be accurately replicated and the chromatin landscape reproduced on new DNA. Chromatin and nuclear structure influence where and when DNA replication...... initiates, whereas the replication process itself disrupts chromatin and challenges established patterns of genome regulation. Specialized replication-coupled mechanisms assemble new DNA into chromatin, but epigenome maintenance is a continuous process taking place throughout the cell cycle. If DNA...

  4. Combining high-throughput MALDI-TOF mass spectrometry and isoelectric focusing gel electrophoresis for virtual 2D gel-based proteomics.

    Science.gov (United States)

    Lohnes, Karen; Quebbemann, Neil R; Liu, Kate; Kobzeff, Fred; Loo, Joseph A; Ogorzalek Loo, Rachel R

    2016-07-15

    The virtual two-dimensional gel electrophoresis/mass spectrometry (virtual 2D gel/MS) technology combines the premier, high-resolution capabilities of 2D gel electrophoresis with the sensitivity and high mass accuracy of mass spectrometry (MS). Intact proteins separated by isoelectric focusing (IEF) gel electrophoresis are imaged from immobilized pH gradient (IPG) polyacrylamide gels (the first dimension of classic 2D-PAGE) by matrix-assisted laser desorption/ionization (MALDI) MS. Obtaining accurate intact masses from sub-picomole-level proteins embedded in 2D-PAGE gels or in IPG strips is desirable to elucidate how the protein of one spot identified as protein 'A' on a 2D gel differs from the protein of another spot identified as the same protein, whenever tryptic peptide maps fail to resolve the issue. This task, however, has been extremely challenging. Virtual 2D gel/MS provides access to these intact masses. Modifications to our matrix deposition procedure improve the reliability with which IPG gels can be prepared; the new procedure is described. Development of this MALDI MS imaging (MSI) method for high-throughput MS with integrated 'top-down' MS to elucidate protein isoforms from complex biological samples is described and it is demonstrated that a 4-cm IPG gel segment can now be imaged in approximately 5min. Gel-wide chemical and enzymatic methods with further interrogation by MALDI MS/MS provide identifications, sequence-related information, and post-translational/transcriptional modification information. The MSI-based virtual 2D gel/MS platform may potentially link the benefits of 'top-down' and 'bottom-up' proteomics.

  5. Replication Research and Special Education

    Science.gov (United States)

    Travers, Jason C.; Cook, Bryan G.; Therrien, William J.; Coyne, Michael D.

    2016-01-01

    Replicating previously reported empirical research is a necessary aspect of an evidence-based field of special education, but little formal investigation into the prevalence of replication research in the special education research literature has been conducted. Various factors may explain the lack of attention to replication of special education…

  6. Replication Research and Special Education

    Science.gov (United States)

    Travers, Jason C.; Cook, Bryan G.; Therrien, William J.; Coyne, Michael D.

    2016-01-01

    Replicating previously reported empirical research is a necessary aspect of an evidence-based field of special education, but little formal investigation into the prevalence of replication research in the special education research literature has been conducted. Various factors may explain the lack of attention to replication of special education…

  7. Replication data collection highlights value in diversity of replication attempts

    Science.gov (United States)

    DeSoto, K. Andrew; Schweinsberg, Martin

    2017-01-01

    Researchers agree that replicability and reproducibility are key aspects of science. A collection of Data Descriptors published in Scientific Data presents data obtained in the process of attempting to replicate previously published research. These new replication data describe published and unpublished projects. The different papers in this collection highlight the many ways that scientific replications can be conducted, and they reveal the benefits and challenges of crucial replication research. The organizers of this collection encourage scientists to reuse the data contained in the collection for their own work, and also believe that these replication examples can serve as educational resources for students, early-career researchers, and experienced scientists alike who are interested in learning more about the process of replication. PMID:28291224

  8. Transmission of white spot syndrome virus (WSSV) from Dendronereis spp. (Peters) (Nereididae) to penaeid shrimp

    NARCIS (Netherlands)

    Haryadi, D.; Verreth, J.A.J.; Verdegem, M.C.J.; Vlak, J.M.

    2015-01-01

    Dendronereis spp. (Peters) (Nereididae) is a common polychaete in shrimp ponds built on intertidal land and is natural food for shrimp in traditionally managed ponds in Indonesia. White spot syndrome virus (WSSV), an important viral pathogen of the shrimp, can replicate in this polychaete (Desrina e

  9. Analysis of the transcription initiation mechanism of tomato spotted wilt virus

    NARCIS (Netherlands)

    Duijsings, D.M.J.M.

    2001-01-01

    Genome replication and transcription of Tomato spotted wilt virus (TSWV, genus Tospovirus ) follows in most aspects the general rules for negative strand RNA viruses with segmented genomes. One common feature is the occurrence of "cap snatching" during transcription initiation. During this process,

  10. Anatomy of Mammalian Replication Domains

    Science.gov (United States)

    Takebayashi, Shin-ichiro; Ogata, Masato; Okumura, Katsuzumi

    2017-01-01

    Genetic information is faithfully copied by DNA replication through many rounds of cell division. In mammals, DNA is replicated in Mb-sized chromosomal units called “replication domains.” While genome-wide maps in multiple cell types and disease states have uncovered both dynamic and static properties of replication domains, we are still in the process of understanding the mechanisms that give rise to these properties. A better understanding of the molecular basis of replication domain regulation will bring new insights into chromosome structure and function. PMID:28350365

  11. Pharmacodynamic activity of Dapivirine and Maraviroc single entity and combination topical gels for HIV-1 prevention

    Science.gov (United States)

    Dezzutti, Charlene S.; Yandura, Sarah; Wang, Lin; Moncla, Bernard; Teeple, Elizabeth A.; Devlin, Brid; Nuttall, Jeremy; Brown, Elizabeth R.; Rohan, Lisa C.

    2015-01-01

    Purpose Dapivirine (DPV), a non-nucleoside reverse transcriptase inhibitor, and maraviroc (MVC), a CCR5 antagonist, were formulated into aqueous gels designed to prevent mucosal HIV transmission. Methods 0.05% DPV, 0.1% MVC, 0.05% DPV/0.1% MVC and placebo gels were evaluated for pH, viscosity, osmolality, and in vitro release. In vitro assays and mucosal tissues were used to evaluate anti-HIV activity. Viability (Lactobacilli only) and epithelial integrity in cell lines and mucosal tissues defined safety. Results The gels were acidic and viscous. DPV gel had an osmolality of 893 mOsm/kg while the other gels had an osmolality of <100 mOsm/kg. MVC release was similar from the single and combination gels (~5 μg/cm2/min1/2), while DPV release was 10-fold less from the single as compared to the combination gel (0.4331 μg/cm2/min1/2). Titrations of the gels showed 10-fold more drug was needed to protect ectocervical than colonic tissue. The combination gel showed ~10- and 100-fold improved activity as compared to DPV and MVC gel, respectively. All gels were safe. Conclusions The DPV/MVC gel showed a benefit blocking HIV infection of mucosal tissue compared to the single entity gels. Combination products with drugs affecting unique steps in the viral replication cycle would be advantageous for HIV prevention. PMID:26078001

  12. Spotting a fake[Telling natural and synthetic diamonds apart

    Energy Technology Data Exchange (ETDEWEB)

    Lawson, S. [Diamond Trading Company, Maidenhead, Berkshire (United Kingdom)]. E-mail: simon.lawson@dtc.com

    2006-06-15

    Diamonds are highly prized for their dazzling appearance and hardness, but would you be able to spot one that had been created in the laboratory? Simon Lawson describes how physics-based techniques can distinguish between natural and synthetic stones. For the last 50 years or so we have been able to make synthetic diamonds that replicate the superlative physical and chemical properties of natural diamonds, and these are used largely for industrial applications. But in the mind of the consumer, there is far more to a diamond than its hardness or brilliance. Research commissioned by the Diamond Trading Company (DTC) has shown that 94% of women surveyed prefer natural diamonds over synthetic ones as a symbol of love, possibly as a result of the immense age of natural stones. One of the key research activities at the DTC is therefore to ensure that synthetic diamonds can be spotted easily. (U.K.)

  13. Mechanically induced gel formation

    NARCIS (Netherlands)

    van Herpt, Jochem T.; Stuart, Marc C. A.; Browne, Wesley R.; Feringa, Ben L.

    2013-01-01

    Mechanical triggering of gelation of an organic solution by a carbazole-based bisurea organogelator is described. Both the duration of the mechanical stimulation and the gelator concentration control the gelation process and the characteristics of the gel obtained.

  14. Conformance Improvement Using Gels

    Energy Technology Data Exchange (ETDEWEB)

    Seright, Randall S.; Schrader, Richard; II Hagstrom, John; Wang, Ying; Al-Dahfeeri, Abdullah; Gary, Raven; Marin; Amaury; Lindquist, Brent

    2002-09-26

    This research project had two objectives. The first objective was to identify gel compositions and conditions that substantially reduce flow through fractures that allow direct channeling between wells, while leaving secondary fractures open so that high fluid injection and production rates can be maintained. The second objective was to optimize treatments in fractured production wells, where the gel must reduce permeability to water much more than that to oil.

  15. Crystallization from Gels

    Science.gov (United States)

    Narayana Kalkura, S.; Natarajan, Subramanian

    Among the various crystallization techniques, crystallization in gels has found wide applications in the fields of biomineralization and macromolecular crystallization in addition to crystallizing materials having nonlinear optical, ferroelectric, ferromagnetic, and other properties. Furthermore, by using this method it is possible to grow single crystals with very high perfection that are difficult to grow by other techniques. The gel method of crystallization provides an ideal technique to study crystal deposition diseases, which could lead to better understanding of their etiology. This chapter focuses on crystallization in gels of compounds that are responsible for crystal deposition diseases. The introduction is followed by a description of the various gels used, the mechanism of gelling, and the fascinating phenomenon of Liesegang ring formation, along with various gel growth techniques. The importance and scope of study on crystal deposition diseases and the need for crystal growth experiments using gel media are stressed. The various crystal deposition diseases, viz. (1) urolithiasis, (2) gout or arthritis, (3) cholelithiasis and atherosclerosis, and (4) pancreatitis and details regarding the constituents of the crystal deposits responsible for the pathological mineralization are discussed. Brief accounts of the theories of the formation of urinary stones and gallstones and the role of trace elements in urinary stone formation are also given. The crystallization in gels of (1) the urinary stone constituents, viz. calcium oxalate, calcium phosphates, uric acid, cystine, etc., (2) the constituents of the gallstones, viz. cholesterol, calcium carbonate, etc., (3) the major constituent of the pancreatic calculi, viz., calcium carbonate, and (4) cholic acid, a steroidal hormone are presented. The effect of various organic and inorganic ions, trace elements, and extracts from cereals, herbs, and fruits on the crystallization of major urinary stone and gallstone

  16. Preparation of chitosan gel

    Directory of Open Access Journals (Sweden)

    Lagerge S.

    2012-06-01

    Full Text Available Aerogel conditioning of the chitosan makes it possible to prepare porous solids of significant specific surface. The increase in the chitosan concentration or the degree of acetylation decreases the specific surface of the synthesized chitosan gel. Whereas drying with supercritical CO2 more effectively makes it possible to preserve the volume of the spheres of gel and to have a more significant specific surface in comparison with evaporative drying.

  17. Modeling inhomogeneous DNA replication kinetics.

    Directory of Open Access Journals (Sweden)

    Michel G Gauthier

    Full Text Available In eukaryotic organisms, DNA replication is initiated at a series of chromosomal locations called origins, where replication forks are assembled proceeding bidirectionally to replicate the genome. The distribution and firing rate of these origins, in conjunction with the velocity at which forks progress, dictate the program of the replication process. Previous attempts at modeling DNA replication in eukaryotes have focused on cases where the firing rate and the velocity of replication forks are homogeneous, or uniform, across the genome. However, it is now known that there are large variations in origin activity along the genome and variations in fork velocities can also take place. Here, we generalize previous approaches to modeling replication, to allow for arbitrary spatial variation of initiation rates and fork velocities. We derive rate equations for left- and right-moving forks and for replication probability over time that can be solved numerically to obtain the mean-field replication program. This method accurately reproduces the results of DNA replication simulation. We also successfully adapted our approach to the inverse problem of fitting measurements of DNA replication performed on single DNA molecules. Since such measurements are performed on specified portion of the genome, the examined DNA molecules may be replicated by forks that originate either within the studied molecule or outside of it. This problem was solved by using an effective flux of incoming replication forks at the model boundaries to represent the origin activity outside the studied region. Using this approach, we show that reliable inferences can be made about the replication of specific portions of the genome even if the amount of data that can be obtained from single-molecule experiments is generally limited.

  18. Technical Stability and Biological Variability in MicroRNAs from Dried Blood Spots: A Lung Cancer Therapy-Monitoring Showcase.

    Science.gov (United States)

    Kahraman, Mustafa; Laufer, Thomas; Backes, Christina; Schrörs, Hannah; Fehlmann, Tobias; Ludwig, Nicole; Kohlhaas, Jochen; Meese, Eckart; Wehler, Thomas; Bals, Robert; Keller, Andreas

    2017-09-01

    Different work flows have been proposed to use miRNAs as blood-borne biomarkers. In particular, the method used for collecting blood from patients can considerably influence the diagnostic results. We explored whether dried blood spots (DBSs) facilitate stable miRNA measurements and compared its technical stability with biological variability. First, we tested the stability of DBS samples by generating from 1 person 18 whole-genome-wide miRNA profiles of DBS samples that were exposed to different temperature and humidity conditions. Second, we investigated technical reproducibility by performing 7 replicates of DBS again from 1 person. Third, we investigated DBS samples from 53 patients with lung cancer undergoing different therapies. Across these 3 stages, 108 genome-wide miRNA profiles from DBS were generated and evaluated biostatistically. In the stability analysis, we observed that temperature and humidity had an overall limited influence on the miRNomes (average correlation between the different conditions of 0.993). Usage of a silica gel slightly diminished DBS' technical reproducibility. The 7 technical replicates had an average correlation of 0.996. The correlation with whole-blood PAXGene miRNomes of the same individual was remarkable (correlation of 0.88). Finally, evaluation of the samples from the 53 patients with lung cancer exposed to different therapies showed that the biological variations exceeded the technical variability significantly (P technical variations significantly. DBS-based miRNA profiles will potentially further the translational character of miRNA biomarker studies. © 2017 American Association for Clinical Chemistry.

  19. CONFORMANCE IMPROVEMENT USING GELS

    Energy Technology Data Exchange (ETDEWEB)

    Randall S. Seright

    2004-09-30

    This report describes work performed during the third and final year of the project, ''Conformance Improvement Using Gels.'' Corefloods revealed throughput dependencies of permeability reduction by polymers and gels that were much more prolonged during oil flow than water flow. This behavior was explained using simple mobility ratio arguments. A model was developed that quantitatively fits the results and predicts ''clean up'' times for oil productivity when production wells are returned to service after application of a polymer or gel treatment. X-ray computed microtomography studies of gels in strongly water-wet Berea sandstone and strongly oil-wet porous polyethylene suggested that oil penetration through gel-filled pores occurs by a gel-dehydration mechanism, rather than gel-ripping or gel-displacement mechanisms. In contrast, analysis of data from the University of Kansas suggests that the gel-ripping or displacement mechanisms are more important in more permeable, strongly water-wet sandpacks. These findings help to explain why aqueous gels can reduce permeability to water more than to oil under different conditions. Since cement is the most commonly used material for water shutoff, we considered when gels are preferred over cements. Our analysis and experimental results indicated that cement cannot be expected to completely fill (top to bottom) a vertical fracture of any width, except near the wellbore. For vertical fractures with apertures less than 4 mm, the cement slurry will simply not penetrate very far into the fracture. For vertical fractures with apertures greater than 4 mm, the slurry may penetrate a substantial distance into the bottom part of the fracture. However, except near the wellbore, the upper part of the fracture will remain open due to gravity segregation. We compared various approaches to plugging fractures using gels, including (1) varying polymer content, (2) varying placement (extrusion) rate

  20. Improved method for identification of low abundance proteins using 2D-gel electrophoresis, MALDI-TOF and TOF/TOF

    Science.gov (United States)

    Introduction: Differential protein expression studies have been routinely performed in our laboratory to determine the health effects of environmentally-important chemicals. In this abstract, improvements in the in-gel protein digestion, MALDI plate spotting and data acquisition...

  1. Improved method for identification of low abundance proteins using 2D-gel electrophoresis, MALDI-TOF and TOF/TOF

    Science.gov (United States)

    Introduction: Differential protein expression studies have been routinely performed in our laboratory to determine the health effects of environmentally-important chemicals. In this abstract, improvements in the in-gel protein digestion, MALDI plate spotting and data acquisition...

  2. Statistical analysis of image data provided by two-dimensional gel electrophoresis for discovery proteomics.

    Science.gov (United States)

    Crossett, Ben; Edwards, Alistair V G; White, Melanie Y; Cordwell, Stuart J

    2008-01-01

    Standardized methods for the solubilization of proteins prior to proteomics analyses incorporating two-dimensional gel electrophoresis (2-DE) are essential for providing reproducible data that can be subjected to rigorous statistical interrogation for comparative studies investigating disease-genesis. In this chapter, we discuss the imaging and image analysis of proteins separated by 2-DE, in the context of determining protein abundance alterations related to a change in biochemical or biophysical conditions. We then describe the principles behind 2-DE gel statistical analysis, including subtraction of background noise, spot detection, gel matching, spot quantitation for data comparison, and statistical requirements to create meaningful gel data sets. We also emphasize the need to develop reproducible and robust protocols for protein sample preparation and 2-DE itself.

  3. [Preparation, characterization and surface-enhanced Raman properties of agarose gel/gold nanoparticles hybrid].

    Science.gov (United States)

    Ma, Xiao-yuan; Liu, Ying; Wang, Zhou-ping

    2014-08-01

    Agarose gel/gold nanoparticles hybrid was prepared by adding gold nanoparticles to preformed agarose gel. Naniocomposite structures and properties were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and UV-Vis-NIR absorption spectroscopy. Experimental data indicated a uniform distribution of gold nanoparticles adsorbed on agarose gel network And the excellent optical absorption properties were shown. Based on the swelling-contraction characteristics of agarose gel and the adjustable localized surface plasmon resonance (LSPR) of the gold nanoparticles, the nano-composites were used as surface enhanced Raman scattering (SERS) substrate to detect the Raman signal molecules Nile blue A. Results revealed that the porous structure of the agarose gel provided a good carrier for the enrichment of the gold nanoparticles. The gold nanoparticles dynamic hot-spot effect arising from the agarose gel contraction loss of water in the air greatly enhanced the Raman signal.

  4. Replicated Spectrographs in Astronomy

    CERN Document Server

    Hill, Gary J

    2014-01-01

    As telescope apertures increase, the challenge of scaling spectrographic astronomical instruments becomes acute. The next generation of extremely large telescopes (ELTs) strain the availability of glass blanks for optics and engineering to provide sufficient mechanical stability. While breaking the relationship between telescope diameter and instrument pupil size by adaptive optics is a clear path for small fields of view, survey instruments exploiting multiplex advantages will be pressed to find cost-effective solutions. In this review we argue that exploiting the full potential of ELTs will require the barrier of the cost and engineering difficulty of monolithic instruments to be broken by the use of large-scale replication of spectrographs. The first steps in this direction have already been taken with the soon to be commissioned MUSE and VIRUS instruments for the Very Large Telescope and the Hobby-Eberly Telescope, respectively. MUSE employs 24 spectrograph channels, while VIRUS has 150 channels. We compa...

  5. SUMO and KSHV Replication

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Pei-Ching [Institute of Microbiology and Immunology, National Yang-Ming University, Taipei 112, Taiwan (China); Kung, Hsing-Jien, E-mail: hkung@nhri.org.tw [Institute for Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan (China); Department of Biochemistry and Molecular Medicine, University of California, Davis, CA 95616 (United States); UC Davis Cancer Center, University of California, Davis, CA 95616 (United States); Division of Molecular and Genomic Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 35053, Taiwan (China)

    2014-09-29

    Small Ubiquitin-related MOdifier (SUMO) modification was initially identified as a reversible post-translational modification that affects the regulation of diverse cellular processes, including signal transduction, protein trafficking, chromosome segregation, and DNA repair. Increasing evidence suggests that the SUMO system also plays an important role in regulating chromatin organization and transcription. It is thus not surprising that double-stranded DNA viruses, such as Kaposi’s sarcoma-associated herpesvirus (KSHV), have exploited SUMO modification as a means of modulating viral chromatin remodeling during the latent-lytic switch. In addition, SUMO regulation allows the disassembly and assembly of promyelocytic leukemia protein-nuclear bodies (PML-NBs), an intrinsic antiviral host defense, during the viral replication cycle. Overcoming PML-NB-mediated cellular intrinsic immunity is essential to allow the initial transcription and replication of the herpesvirus genome after de novo infection. As a consequence, KSHV has evolved a way as to produce multiple SUMO regulatory viral proteins to modulate the cellular SUMO environment in a dynamic way during its life cycle. Remarkably, KSHV encodes one gene product (K-bZIP) with SUMO-ligase activities and one gene product (K-Rta) that exhibits SUMO-targeting ubiquitin ligase (STUbL) activity. In addition, at least two viral products are sumoylated that have functional importance. Furthermore, sumoylation can be modulated by other viral gene products, such as the viral protein kinase Orf36. Interference with the sumoylation of specific viral targets represents a potential therapeutic strategy when treating KSHV, as well as other oncogenic herpesviruses. Here, we summarize the different ways KSHV exploits and manipulates the cellular SUMO system and explore the multi-faceted functions of SUMO during KSHV’s life cycle and pathogenesis.

  6. Laser based spot weld characterization

    Science.gov (United States)

    Jonietz, Florian; Myrach, Philipp; Rethmeier, Michael; Suwala, Hubert; Ziegler, Mathias

    2016-02-01

    Spot welding is one of the most important joining technologies, especially in the automotive industry. Hitherto, the quality of spot welded joints is tested mainly by random destructive tests. A nondestructive testing technique offers the benefit of cost reduction of the testing procedure and optimization of the fabrication process, because every joint could be examined. This would lead to a reduced number of spot welded joints, as redundancies could be avoided. In the procedure described here, the spot welded joint between two zinc-coated steel sheets (HX340LAD+Z100MB or HC340LA+ZE 50/50) is heated optically on one side. Laser radiation and flash light are used as heat sources. The melted zone, the so called "weld nugget" provides the mechanical stability of the connection, but also constitutes a thermal bridge between the sheets. Due to the better thermal contact, the spot welded joint reveals a thermal behavior different from the surrounding material, where the heat transfer between the two sheets is much lower. The difference in the transient thermal behavior is measured with time resolved thermography. Hence, the size of the thermal contact between the two sheets is determined, which is directly correlated to the size of the weld nugget, indicating the quality of the spot weld. The method performs well in transmission with laser radiation and flash light. With laser radiation, it works even in reflection geometry, thus offering the possibility of testing with just one-sided accessibility. By using heating with collimated laser radiation, not only contact-free, but also remote testing is feasible. A further convenience compared to similar thermographic approaches is the applicability on bare steel sheets without any optical coating for emissivity correction. For this purpose, a proper way of emissivity correction was established.

  7. Design of Autonomous Gel Actuators

    Directory of Open Access Journals (Sweden)

    Shuji Hashimoto

    2011-01-01

    Full Text Available In this paper, we introduce autonomous gel actuators driven by chemical energy. The polymer gels prepared here have cyclic chemical reaction networks. With a cyclic reaction, the polymer gels generate periodical motion. The periodic motion of the gel is produced by the chemical energy of the oscillatory Belouzov-Zhabotinsky (BZ reaction. We have succeeded in making synthetic polymer gel move autonomously like a living organism. This experimental fact represents the great possibility of the chemical robot.

  8. Is this Red Spot the Blue Spot (locus ceruleum)?

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Won Sick; Lee, Yu Kyung; Lee, Min Kyung; Hwang, Kyung Hoon [Gachon University Gil Hospital, Incheon (Korea, Republic of)

    2010-06-15

    The authors report brain images of 18F-FDG-PET in a case of schizophrenia. The images showed strikingly increased bilateral uptake in the locus ceruleum. The locus ceruleum is called the blue spot and known to be a center of the norepinephrinergic system.

  9. Pulsed-field gel electrophoresis of bacterial chromosomes.

    Science.gov (United States)

    Mawer, Julia S P; Leach, David R F

    2013-01-01

    The separation of fragments of DNA by agarose gel electrophoresis is integral to laboratory life. Nevertheless, standard agarose gel electrophoresis cannot resolve fragments bigger than 50 kb. Pulsed-field gel electrophoresis is a technique that has been developed to overcome the limitations of standard agarose gel electrophoresis. Entire linear eukaryotic chromosomes, or large fragments of a chromosome that have been generated by the action of rare-cutting restriction endonucleases, can be separated using this technique. As a result, pulsed-field gel electrophoresis has many applications, from karyotype analysis of microbial genomes, to the analysis of chromosomal strand breaks and their repair intermediates, to the study of DNA replication and the identification of origins of replication. This chapter presents a detailed protocol for the preparation of Escherichia coli chromosomal DNA that has been embedded in agarose plugs, digested with the rare-cutting endonuclease NotI, and separated by contour-clamped homogeneous field electrophoresis. The principles in this protocol can be applied to the separation of all fragments of DNA whose size range is between 40 kb and 1 Mb.

  10. Differentiation of black gel inks using optical and chemical techniques.

    Science.gov (United States)

    Wilson, Jeffrey D; LaPorte, Gerald M; Cantu, Antonio A

    2004-03-01

    Gel ink pens have become a common writing instrument in the United States. Questioned document examiners often attempt to optically differentiate gel inks from each other and from other non-ballpoint ink writings (e.g., those from roller-ball pens). Since early formulations were primarily pigment-based, they do not elute when analyzed by thin-layer chromatography. However, recent gel ink formulations (i.e., within the past five years) include dye-based inks that can be easily separated. This study differentiates black gel inks using optical and chemical techniques. The techniques include: microscopy, visible and near infrared reflectance, near infrared luminescence, thin-layer chromatography (TLC), spot tests, and gas chromatography/mass spectrometry (GC/MS). As a result of this study a flow chart has been developed allowing for a systematic determination of a questioned ink. In addition, an analysis of volatile compounds found in gel inks revealed that there are some unique ingredients that may be found in gel inks that are not typically found in other non-ballpoint inks.

  11. Efficient usage of Adabas replication

    CERN Document Server

    Storr, Dieter W

    2011-01-01

    In today's IT organization replication becomes more and more an essential technology. This makes Software AG's Event Replicator for Adabas an important part of your data processing. Setting the right parameters and establishing the best network communication, as well as selecting efficient target components, is essential for successfully implementing replication. This book provides comprehensive information and unique best-practice experience in the field of Event Replicator for Adabas. It also includes sample codes and configurations making your start very easy. It describes all components ne

  12. Solving the Telomere Replication Problem

    Science.gov (United States)

    Maestroni, Laetitia; Matmati, Samah; Coulon, Stéphane

    2017-01-01

    Telomeres are complex nucleoprotein structures that protect the extremities of linear chromosomes. Telomere replication is a major challenge because many obstacles to the progression of the replication fork are concentrated at the ends of the chromosomes. This is known as the telomere replication problem. In this article, different and new aspects of telomere replication, that can threaten the integrity of telomeres, will be reviewed. In particular, we will focus on the functions of shelterin and the replisome for the preservation of telomere integrity. PMID:28146113

  13. Gel electrolytes and electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Fleischmann, Sven; Bunte, Christine; Mikhaylik, Yuriy V.; Viner, Veronika G.

    2017-09-05

    Gel electrolytes, especially gel electrolytes for electrochemical cells, are generally described. In some embodiments, the gel electrolyte layers comprise components a) to c). Component a) may be at least one layer of at least one polymer comprising polymerized units of: a1) at least one monomer containing an ethylenically unsaturated unit and an amido group and a2) at least one crosslinker. Component b) may be at least one conducting salt and component c) may be at least one solvent. Electrodes may comprise the components a), d) and e), wherein component a) may be at least one layer of at least one polymer as described herein. Component d) may be at least one electroactive layer and component e) may be at least one ceramic layer. Furthermore, electrochemical cells comprising component a) which may be at least one layer of at least one polymer as described herein, are also provided.

  14. Active Polymer Gel Actuators

    Directory of Open Access Journals (Sweden)

    Shuji Hashimoto

    2010-01-01

    Full Text Available Many kinds of stimuli-responsive polymer and gels have been developed and applied to biomimetic actuators or artificial muscles. Electroactive polymers that change shape when stimulated electrically seem to be particularly promising. In all cases, however, the mechanical motion is driven by external stimuli, for example, reversing the direction of electric field. On the other hand, many living organisms can generate an autonomous motion without external driving stimuli like self-beating of heart muscles. Here we show a novel biomimetic gel actuator that can walk spontaneously with a wormlike motion without switching of external stimuli. The self-oscillating motion is produced by dissipating chemical energy of oscillating reaction. Although the gel is completely composed of synthetic polymer, it shows autonomous motion as if it were alive.

  15. The puzzling MILAGRO hot spots

    CERN Document Server

    Drury, Luke

    2008-01-01

    We discuss the reported detection by the MILAGRO experiment of localised hot spots in the cosmic ray arrival distribution and the difficulty of interpreting these observations. A model based on secondary neutron production in the heliotail is shown to fail. An alternative model based on loss-cone leakage through a magnetic trap from a local source region is proposed.

  16. Charter School Replication. Policy Guide

    Science.gov (United States)

    Rhim, Lauren Morando

    2009-01-01

    "Replication" is the practice of a single charter school board or management organization opening several more schools that are each based on the same school model. The most rapid strategy to increase the number of new high-quality charter schools available to children is to encourage the replication of existing quality schools. This policy guide…

  17. Electron microscopic analysis of rotavirus assembly-replication intermediates

    Energy Technology Data Exchange (ETDEWEB)

    Boudreaux, Crystal E.; Kelly, Deborah F. [Virginia Tech Carilion School of Medicine and Research Institute, Roanoke, VA (United States); McDonald, Sarah M., E-mail: mcdonaldsa@vtc.vt.edu [Virginia Tech Carilion School of Medicine and Research Institute, Roanoke, VA (United States); Department of Biomedical Sciences and Pathobiology, Virginia—Maryland Regional College of Veterinary Medicine, Blacksburg, VA (United States)

    2015-03-15

    Rotaviruses (RVs) replicate their segmented, double-stranded RNA genomes in tandem with early virion assembly. In this study, we sought to gain insight into the ultrastructure of RV assembly-replication intermediates (RIs) using transmission electron microscopy (EM). Specifically, we examined a replicase-competent, subcellular fraction that contains all known RV RIs. Three never-before-seen complexes were visualized in this fraction. Using in vitro reconstitution, we showed that ~15-nm doughnut-shaped proteins in strings were nonstructural protein 2 (NSP2) bound to viral RNA transcripts. Moreover, using immunoaffinity-capture EM, we revealed that ~20-nm pebble-shaped complexes contain the viral RNA polymerase (VP1) and RNA capping enzyme (VP3). Finally, using a gel purification method, we demonstrated that ~30–70-nm electron-dense, particle-shaped complexes represent replicase-competent core RIs, containing VP1, VP3, and NSP2 as well as capsid proteins VP2 and VP6. The results of this study raise new questions about the interactions among viral proteins and RNA during the concerted assembly–replicase process. - Highlights: • Rotaviruses replicate their genomes in tandem with early virion assembly. • Little is known about rotavirus assembly-replication intermediates. • Assembly-replication intermediates were imaged using electron microscopy.

  18. LHCb experience with LFC replication

    CERN Document Server

    Bonifazi, F; Perez, E D; D'Apice, A; dell'Agnello, L; Düllmann, D; Girone, M; Re, G L; Martelli, B; Peco, G; Ricci, P P; Sapunenko, V; Vagnoni, V; Vitlacil, D

    2008-01-01

    Database replication is a key topic in the framework of the LHC Computing Grid to allow processing of data in a distributed environment. In particular, the LHCb computing model relies on the LHC File Catalog, i.e. a database which stores information about files spread across the GRID, their logical names and the physical locations of all the replicas. The LHCb computing model requires the LFC to be replicated at Tier-1s. The LCG 3D project deals with the database replication issue and provides a replication service based on Oracle Streams technology. This paper describes the deployment of the LHC File Catalog replication to the INFN National Center for Telematics and Informatics (CNAF) and to other LHCb Tier-1 sites. We performed stress tests designed to evaluate any delay in the propagation of the streams and the scalability of the system. The tests show the robustness of the replica implementation with performance going much beyond the LHCb requirements.

  19. DATABASE REPLICATION IN HETEROGENOUS PLATFORM

    Directory of Open Access Journals (Sweden)

    Hendro Nindito

    2014-01-01

    Full Text Available The application of diverse database technologies in enterprises today is increasingly a common practice. To provide high availability and survavibality of real-time information, a database replication technology that has capability to replicate databases under heterogenous platforms is required. The purpose of this research is to find the technology with such capability. In this research, the data source is stored in MSSQL database server running on Windows. The data will be replicated to MySQL running on Linux as the destination. The method applied in this research is prototyping in which the processes of development and testing can be done interactively and repeatedly. The key result of this research is that the replication technology applied, which is called Oracle GoldenGate, can successfully manage to do its task in replicating data in real-time and heterogeneous platforms.

  20. LHCb experience with LFC replication

    CERN Document Server

    Carbone, Angelo; Dafonte Perez, Eva; D'Apice, Antimo; dell'Agnello, Luca; Duellmann, Dirk; Girone, Maria; Lo Re, Giuseppe; Martelli, Barbara; Peco, Gianluca; Ricci, Pier Paolo; Sapunenko, Vladimir; Vagnoni, Vincenzo; Vitlacil, Dejan

    2007-01-01

    Database replication is a key topic in the framework of the LHC Computing Grid to allow processing of data in a distributed environment. In particular, the LHCb computing model relies on the LHC File Catalog, i.e. database which stores information about files spread across the GRID, their logical names and the physical locations of all the replicas. The LHCb computing model requires the LFC to be replicated at Tier-1s. The LCG 3D project deals with the database replication issue and provides a replication service based on Oracle Streams technology. This paper describes the deployment of the LHC File Catalog replication to the INFN National Center for Telematics and Informations (CNAF) and to other LHCb Tier-1 sites. We performed stress tests designed to evaluate any delay in the propagation of the streams and the scalability of the system. The tests show the robustness of the replica implementation with performance going much beyond the LHCb requirements.

  1. gonarthrosis; therapy; Karmolis gel.

    Directory of Open Access Journals (Sweden)

    B. V. Zavodovsky

    2014-01-01

    Full Text Available Objective: to evaluate the efficacy, tolerance, and safety of Carmolis topical gel in patients with gonarthrosis. Subjects and methods. The investigation enrolled 60 patients with knee osteoarthrosis (OA who were divided into two groups: 1 40 patients received Carmolis topical gel in addition to nonsteroidal anti-inflammatory drugs (NSAIDs; 2 20 patients took NSAIDS only (a control group. The treatment duration was 2 weeks. In both groups, therapeutic effectiveness was evaluated from changes in the WOMAC index, pain intensity at rest and during movement by the visual analog scale (VAS. The disease activity was also assessed by a physician and a patient (a Likert scale, local swelling and hyperthermia of the affected joint, the efficiency of treatment, and daily needs for NSAIDs were deter- mined. Results. The performed treatment in both patent groups showed positive clinical changes. Combination therapy involving Carmolis gel displayed greater reductions in WOMAC pain and resting and movement pain than in the con- trol group (as assessed by VAS. On completion of the investigation, considerable improvement was, in the physicians' opinion, noted in 38 (95% patients using Carmolis, which coincided with self-evaluations of the patients. During Carmolis application, the starting dose of NSAIDs could be reduced in 18 (45% patients. Adverse reactions occurred infrequently and required no therapy discontinuation. Conclusion. Carmolis topical gel is effective in relieving clinical symptoms in patients with gonarthrosis, well tolerated, and safe, which can recommend its use in the combination treatment of knee OA.

  2. SPOT- 4 North American Data Buy

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS has contracted with SPOT Image Corporation to acquire and provide Satellite Pour l'Observation de la Terre (SPOT) satellite data for calendar years 2010 and...

  3. SPOT 5 North American Data Buy

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS has contracted with SPOT Image Corporation to acquire and provide Satellite Pour l'Observation de la Terre (SPOT) satellite data for calendar years 2010 and...

  4. Rocky Mountain Spotted Fever: Statistics and Epidemiology

    Science.gov (United States)

    ... The CDC Cancel Submit Search The CDC Rocky Mountain Spotted Fever (RMSF) Note: Javascript is disabled or ... please visit this page: About CDC.gov . Rocky Mountain Spotted Fever (RMSF) Symptoms, Diagnosis, and Treatment Statistics ...

  5. SPOT- 5 North American Data Buy

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS has contracted with SPOT Image Corporation to acquire and provide Satellite Pour l'Observation de la Terre (SPOT) satellite data for calendar years 2010 and...

  6. SPOT 4 North American Data Buy

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS has contracted with SPOT Image Corporation to acquire and provide Satellite Pour l'Observation de la Terre (SPOT) satellite data for calendar years 2010 and...

  7. PHProteomicDB: A Module for Two-dimensional Gel Electrophoresis Database Creation on Personal Web Sites

    Institute of Scientific and Technical Information of China (English)

    Pascal Pernet; Arnaud Bruneel; Bruno Baudin; Michel Vaubourdolle

    2006-01-01

    PHProteomicDB is a PHP-written module to help researchers in proteomics to share two-dimensional gel electrophoresis data using personal web sites. No technical or PHP knowledge is necessary except a few basics about web site management. PHProteomicDB has a user-friendly administration interface to enter and update data. It creates web pages on the fly displaying gel characteristics,gel pictures, and numbered gel spots with their related identifications pointing to their reference pages in protein databanks. The module is freely available at http://www.huvec.com/index.php3?rub=Download.

  8. Improvements on analytic modelling of stellar spots

    CERN Document Server

    Montalto, M; Oshagh, M; Boisse, I; Bruno, G; Santos, N C

    2014-01-01

    In this work we present the solution of the stellar spot problem using the Kelvin-Stokes theorem. Our result is applicable for any given location and dimension of the spots on the stellar surface. We present explicitely the result up to the second degree in the limb darkening law. This technique can be used to calculate very efficiently mutual photometric effects produced by eclipsing bodies occulting stellar spots and to construct complex spot shapes.

  9. NACSA Charter School Replication Guide: The Spectrum of Replication Options. Authorizing Matters. Replication Brief 1

    Science.gov (United States)

    O'Neill, Paul

    2010-01-01

    One of the most important and high-profile issues in public education reform today is the replication of successful public charter school programs. With more than 5,000 failing public schools in the United States, there is a tremendous need for strong alternatives for parents and students. Replicating successful charter school models is an…

  10. Rocky Mountain Spotted Fever (For Parents)

    Science.gov (United States)

    ... Feeding Your 1- to 2-Year-Old Rocky Mountain Spotted Fever KidsHealth > For Parents > Rocky Mountain Spotted Fever Print A A A What's in ... en español La rickettsiosis maculosa About RMSF Rocky Mountain spotted fever (RMSF) is a bacterial infection that's ...

  11. 9 CFR 149.4 - Spot audit.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Spot audit. 149.4 Section 149.4... LIVESTOCK IMPROVEMENT VOLUNTARY TRICHINAE CERTIFICATION PROGRAM § 149.4 Spot audit. (a) In addition to regularly scheduled site audits, certified production sites will be subject to spot audits. (1) Random...

  12. Investigation of two different anoxia models by 2-dimensional gel electrophoresis

    DEFF Research Database (Denmark)

    Wulff, Tune; Jessen, Flemming; Hoffmann, Else Kay

    2006-01-01

    anoxia obtained by NaN3 is a widely used model for simulating anoxia (Ossum et al., 2004). The effects of anoxia were studied by protein expression analysis using 2-dimensional gel electrophoresis followed by MS/MS. In this way we were able to separate more than 1500 protein spots with an apparent range...

  13. Investigation of two different anoxia models by 2-dimensional gel electrophoresis

    DEFF Research Database (Denmark)

    Wulff, Tune; Jessen, Flemming; Hoffmann, Else Kay

    2006-01-01

    anoxia obtained by NaN3 is a widely used model for simulating anoxia (Ossum et al., 2004). The effects of anoxia were studied by protein expression analysis using 2-dimensional gel electrophoresis followed by MS/MS. In this way we were able to separate more than 1500 protein spots with an apparent range...

  14. Reproduction of two-spotted goby, Gobiusculus flavescens, in captivity

    Directory of Open Access Journals (Sweden)

    Vera Teles

    2014-06-01

    Full Text Available The two-spotted goby, Gobiusculus flavescens, is a common fish species along rocky shores in northern European waters. It is a small (40-60 mm, semipelagic marine fish, forming loose shoals in association with microalgae vegetation and mussel beds growing on the rock surface. It is a short-lived species, with a life span of 1-2 years. Both sexes display courtship behaviour and have sexual ornamentation during the breeding season. Male ornaments consist of large dorsal fins with iridescent blue lines, and iridescent blue spots along the sides of the body. Females develop a conspicuous, bright orange belly at sexual maturity. Due to these characteristics this species could have a great interest for ornamental aquariums. In previous work the maintenance of G. flavescens at high temperatures (until 23°C was successful. The aim of this study was to test the reproduction in captivity of G. flavescens. Six replicates were used (18L aquariums at the temperature of 18°C. In each replicate, two males and four females were introduced to an aquarium, where the males chose between two nests and courted the females. During the 112 days of the experiment the females spawned five times but only three spawns had success. The eggs take approximately 8 days to become mature. On the three spawns have hatched 300, 361 and 510 larvae at a time. The larvae were kept in a separate container and fed with alive rotifers and survived a maximum of 21 days. The reproduction of the two-spotted goby in captivity is possible at 18°C, but it is necessary to improve the conditions to rearing the larvae.

  15. Partial Purification of a Megadalton DNA Replication Complex by Free Flow Electrophoresis

    Science.gov (United States)

    Li, Caroline M.; Miao, Yunan; Lingeman, Robert G.; Hickey, Robert J.; Malkas, Linda H.

    2016-01-01

    We describe a gentle and rapid method to purify the intact multiprotein DNA replication complex using free flow electrophoresis (FFE). In particular, we applied FFE to purify the human cell DNA synthesome, which is a multiprotein complex that is fully competent to carry-out all phases of the DNA replication process in vitro using a plasmid containing the simian virus 40 (SV40) origin of DNA replication and the viral large tumor antigen (T-antigen) protein. The isolated native DNA synthesome can be of use in studying the mechanism by which mammalian DNA replication is carried-out and how anti-cancer drugs disrupt the DNA replication or repair process. Partially purified extracts from HeLa cells were fractionated in a native, liquid based separation by FFE. Dot blot analysis showed co-elution of many proteins identified as part of the DNA synthesome, including proliferating cell nuclear antigen (PCNA), DNA topoisomerase I (topo I), DNA polymerase δ (Pol δ), DNA polymerase ɛ (Pol ɛ), replication protein A (RPA) and replication factor C (RFC). Previously identified DNA synthesome proteins co-eluted with T-antigen dependent and SV40 origin-specific DNA polymerase activity at the same FFE fractions. Native gels show a multiprotein PCNA containing complex migrating with an apparent relative mobility in the megadalton range. When PCNA containing bands were excised from the native gel, mass spectrometric sequencing analysis identified 23 known DNA synthesome associated proteins or protein subunits. PMID:28036377

  16. International Expansion through Flexible Replication

    DEFF Research Database (Denmark)

    Jonsson, Anna; Foss, Nicolai Juul

    2011-01-01

    to local environments and under the impact of new learning. To illuminate these issues, we draw on a longitudinal in-depth study of Swedish home furnishing giant IKEA, involving more than 70 interviews. We find that IKEA has developed organizational mechanisms that support an ongoing learning process aimed......, etc.) are replicated in a uniform manner across stores, and change only very slowly (if at all) in response to learning (“flexible replication”). We conclude by discussing the factors that influence the approach to replication adopted by an international replicator....

  17. The Psychology of Replication and Replication in Psychology.

    Science.gov (United States)

    Francis, Gregory

    2012-11-01

    Like other scientists, psychologists believe experimental replication to be the final arbiter for determining the validity of an empirical finding. Reports in psychology journals often attempt to prove the validity of a hypothesis or theory with multiple experiments that replicate a finding. Unfortunately, these efforts are sometimes misguided because in a field like experimental psychology, ever more successful replication does not necessarily ensure the validity of an empirical finding. When psychological experiments are analyzed with statistics, the rules of probability dictate that random samples should sometimes be selected that do not reject the null hypothesis, even if an effect is real. As a result, it is possible for a set of experiments to have too many successful replications. When there are too many successful replications for a given set of experiments, a skeptical scientist should be suspicious that null or negative findings have been suppressed, the experiments were run improperly, or the experiments were analyzed improperly. This article describes the implications of this observation and demonstrates how to test for too much successful replication by using a set of experiments from a recent research paper.

  18. Regulation of Replication Recovery and Genome Integrity

    DEFF Research Database (Denmark)

    Colding, Camilla Skettrup

    Preserving genome integrity is essential for cell survival. To this end, mechanisms that supervise DNA replication and respond to replication perturbations have evolved. One such mechanism is the replication checkpoint, which responds to DNA replication stress and acts to ensure replication pausing...

  19. A spot test for detection of cobalt release – early experience and findings

    DEFF Research Database (Denmark)

    Thyssen, Jacob P.; Menné, Torkil; Johansen, Jeanne D.

    2010-01-01

    Background: It is often difficult to establish clinical relevance of metal exposure in cobalt-allergic patients. Dermatologists and patients may incorrectly assume that many metallic items release cobalt at levels that may cause cobalt dermatitis. Cobalt-allergic patients may be unaware...... that they are exposed to cobalt from handling work items, causing hand dermatitis. Objectives: To present early findings with a newly developed cobalt spot test. Methods and Results: A cobalt spot test based on disodium-1-nitroso-2-naphthol-3,6-disulfonate was able to identify cobalt release at 8.3 ppm. The test may...... also be used as a gel test if combined with an agar preparation. We found no false-positive reactions when testing metals and alloys known not to contain cobalt. However, one cobalt-containing alloy, which elicited cobalt dermatitis in cobalt-allergic patients, was negative upon cobalt gel testing...

  20. Active Polymer Gel Actuators

    OpenAIRE

    Shuji Hashimoto; Ryo Yoshida; Yusuke Hara; Shingo Maeda

    2010-01-01

    Many kinds of stimuli-responsive polymer and gels have been developed and applied to biomimetic actuators or artificial muscles. Electroactive polymers that change shape when stimulated electrically seem to be particularly promising. In all cases, however, the mechanical motion is driven by external stimuli, for example, reversing the direction of electric field. On the other hand, many living organisms can generate an autonomous motion without external driving stimuli like self-beating of he...

  1. Biomarkers of replicative senescence revisited

    DEFF Research Database (Denmark)

    Nehlin, Jan

    2016-01-01

    Biomarkers of replicative senescence can be defined as those ultrastructural and physiological variations as well as molecules whose changes in expression, activity or function correlate with aging, as a result of the gradual exhaustion of replicative potential and a state of permanent cell cycle...... with their chronological age and present health status, help define their current rate of aging and contribute to establish personalized therapy plans to reduce, counteract or even avoid the appearance of aging biomarkers....

  2. Nucleotide Metabolism and DNA Replication.

    Science.gov (United States)

    Warner, Digby F; Evans, Joanna C; Mizrahi, Valerie

    2014-10-01

    The development and application of a highly versatile suite of tools for mycobacterial genetics, coupled with widespread use of "omics" approaches to elucidate the structure, function, and regulation of mycobacterial proteins, has led to spectacular advances in our understanding of the metabolism and physiology of mycobacteria. In this article, we provide an update on nucleotide metabolism and DNA replication in mycobacteria, highlighting key findings from the past 10 to 15 years. In the first section, we focus on nucleotide metabolism, ranging from the biosynthesis, salvage, and interconversion of purine and pyrimidine ribonucleotides to the formation of deoxyribonucleotides. The second part of the article is devoted to DNA replication, with a focus on replication initiation and elongation, as well as DNA unwinding. We provide an overview of replication fidelity and mutation rates in mycobacteria and summarize evidence suggesting that DNA replication occurs during states of low metabolic activity, and conclude by suggesting directions for future research to address key outstanding questions. Although this article focuses primarily on observations from Mycobacterium tuberculosis, it is interspersed, where appropriate, with insights from, and comparisons with, other mycobacterial species as well as better characterized bacterial models such as Escherichia coli. Finally, a common theme underlying almost all studies of mycobacterial metabolism is the potential to identify and validate functions or pathways that can be exploited for tuberculosis drug discovery. In this context, we have specifically highlighted those processes in mycobacterial DNA replication that might satisfy this critical requirement.

  3. Plasmid Rolling-Circle Replication.

    Science.gov (United States)

    Ruiz-Masó, J A; MachóN, C; Bordanaba-Ruiseco, L; Espinosa, M; Coll, M; Del Solar, G

    2015-02-01

    Plasmids are DNA entities that undergo controlled replication independent of the chromosomal DNA, a crucial step that guarantees the prevalence of the plasmid in its host. DNA replication has to cope with the incapacity of the DNA polymerases to start de novo DNA synthesis, and different replication mechanisms offer diverse solutions to this problem. Rolling-circle replication (RCR) is a mechanism adopted by certain plasmids, among other genetic elements, that represents one of the simplest initiation strategies, that is, the nicking by a replication initiator protein on one parental strand to generate the primer for leading-strand initiation and a single priming site for lagging-strand synthesis. All RCR plasmid genomes consist of a number of basic elements: leading strand initiation and control, lagging strand origin, phenotypic determinants, and mobilization, generally in that order of frequency. RCR has been mainly characterized in Gram-positive bacterial plasmids, although it has also been described in Gram-negative bacterial or archaeal plasmids. Here we aim to provide an overview of the RCR plasmids' lifestyle, with emphasis on their characteristic traits, promiscuity, stability, utility as vectors, etc. While RCR is one of the best-characterized plasmid replication mechanisms, there are still many questions left unanswered, which will be pointed out along the way in this review.

  4. ESA uncovers Geminga's `hot spot'

    Science.gov (United States)

    2004-07-01

    16 July 2004 Astronomers using ESA’s X-ray observatory XMM-Newton have detected a small, bright ‘hot spot’ on the surface of the neutron star called Geminga, 500 light-years away. The hot spot is the size of a football field and is caused by the same mechanism producing Geminga’s X-ray tails. This discovery identifies the missing link between the X-ray and gamma-ray emission from Geminga. hi-res Size hi-res: 1284 kb Credits: ESA, P. Caraveo (IASF, Milan) Geminga's hot spot This figure shows the effects of charged particles accelerated in the magnetosphere of Geminga. Panel (a) shows an image taken with the EPIC instrument on board the XMM-Newton observatory. The bright tails, made of particles kicked out by Geminga’s strong magnetic field, trail the neutron star as it moves about in space. Panel (b) shows how electrically charged particles interact with Geminga’s magnetic field. For example, if electrons (blue) are kicked out by the star, positrons (in red) hit the star’s magnetic poles like in an ‘own goal’. Panel (c) illustrates the size of Geminga’s magnetic field (blue) compared to that of the star itself at the centre (purple). The magnetic field is tilted with respect to Geminga’s rotation axis (red). Panel (d) shows the magnetic poles of Geminga, where charged particles hit the surface of the star, creating a two-million degrees hot spot, a region much hotter than the surroundings. As the star spins on its rotation axis, the hot spot comes into view and then disappears, causing the periodic colour change seen by XMM-Newton. An animated version of the entire sequence can be found at: Click here for animated GIF [low resolution, animated GIF, 5536 KB] Click here for AVI [high resolution, AVI with DIVX compression, 19128 KB] hi-res Size hi-res: 371 kb Credits: ESA, P. Caraveo (IASF, Milan) Geminga's hot spot, panel (a) Panel (a) shows an image taken with the EPIC instrument on board the XMM-Newton observatory. The bright tails, made of

  5. Watermarking spot colors in packaging

    Science.gov (United States)

    Reed, Alastair; Filler, TomáÅ.¡; Falkenstern, Kristyn; Bai, Yang

    2015-03-01

    In January 2014, Digimarc announced Digimarc® Barcode for the packaging industry to improve the check-out efficiency and customer experience for retailers. Digimarc Barcode is a machine readable code that carries the same information as a traditional Universal Product Code (UPC) and is introduced by adding a robust digital watermark to the package design. It is imperceptible to the human eye but can be read by a modern barcode scanner at the Point of Sale (POS) station. Compared to a traditional linear barcode, Digimarc Barcode covers the whole package with minimal impact on the graphic design. This significantly improves the Items per Minute (IPM) metric, which retailers use to track the checkout efficiency since it closely relates to their profitability. Increasing IPM by a few percent could lead to potential savings of millions of dollars for retailers, giving them a strong incentive to add the Digimarc Barcode to their packages. Testing performed by Digimarc showed increases in IPM of at least 33% using the Digimarc Barcode, compared to using a traditional barcode. A method of watermarking print ready image data used in the commercial packaging industry is described. A significant proportion of packages are printed using spot colors, therefore spot colors needs to be supported by an embedder for Digimarc Barcode. Digimarc Barcode supports the PANTONE spot color system, which is commonly used in the packaging industry. The Digimarc Barcode embedder allows a user to insert the UPC code in an image while minimizing perceptibility to the Human Visual System (HVS). The Digimarc Barcode is inserted in the printing ink domain, using an Adobe Photoshop plug-in as the last step before printing. Since Photoshop is an industry standard widely used by pre-press shops in the packaging industry, a Digimarc Barcode can be easily inserted and proofed.

  6. Human Cell Chips: Adapting DNA Microarray Spotting Technology to Cell-Based Imaging Assays

    OpenAIRE

    Traver Hart; Alice Zhao; Ankit Garg; Swetha Bolusani; Marcotte, Edward M.

    2009-01-01

    Here we describe human spotted cell chips, a technology for determining cellular state across arrays of cells subjected to chemical or genetic perturbation. Cells are grown and treated under standard tissue culture conditions before being fixed and printed onto replicate glass slides, effectively decoupling the experimental conditions from the assay technique. Each slide is then probed using immunofluorescence or other optical reporter and assayed by automated microscopy. We show potential ap...

  7. Factors influencing alginate gel biocompatibility.

    Science.gov (United States)

    Tam, Susan K; Dusseault, Julie; Bilodeau, Stéphanie; Langlois, Geneviève; Hallé, Jean-Pierre; Yahia, L'Hocine

    2011-07-01

    Alginate remains the most popular polymer used for cell encapsulation, yet its biocompatibility is inconsistent. Two commercially available alginates were compared, one with 71% guluronate (HiG), and the other with 44% (IntG). Both alginates were purified, and their purities were verified. After 2 days in the peritoneal cavity of C57BL/6J mice, barium (Ba)-gel and calcium (Ca)-gel beads of IntG alginate were clean, while host cells were adhered to beads of HiG alginate. IntG gel beads, however, showed fragmentation in vivo while HiG gel beads stayed firm. The physicochemical properties of the sodium alginates and their gels were thoroughly characterized. The intrinsic viscosity of IntG alginate was 2.5-fold higher than that of HiG alginate, suggesting a greater molecular mass. X-ray photoelectron spectroscopy indicated that both alginates were similar in elemental composition, including low levels of counterions in all gels. The wettabilities of the alginates and gels were also identical, as measured by contact angles of water on dry films. Ba-gel beads of HiG alginate resisted swelling and degradation when immersed in water, much more than the other gel beads. These results suggest that the main factors contributing to the biocompatibility of gels of purified alginate are the mannuronate/guluronate content and/or intrinsic viscosity.

  8. A Hot Spot in Coma

    CERN Document Server

    Donnelly, R H; Forman, W R; Jones, C; Churazov, E; Gilfanov, M R

    1999-01-01

    We study the temperature structure of the central part (r<18' ~0.7 h50**-1 Mpc) of the Coma cluster of galaxies using ASCA data. Two different analysis methods produce results in good agreement with each other and reveal the presence of interesting structures in the gas temperature distribution. Globally, the average temperature in the center of the cluster is 9.0 +/- 0.6 keV in good agreement with previous results. Superimposed on this, we find a cool area with temperatures of 4-6 keV associated with a filament of X-ray emission extending southeast from the cluster center detected by Vikhlinin and coworkers. We also find a hot spot with a temperature of around 13 keV displaced north from the central peak of emission. The distribution of the gas temperatures and relative specific entropies suggests that the cool features are most likely gas stripped from a galaxy group centered on NGC 4874 falling toward the core from outside, while the hot spot located ``ahead'' of this in-falling gas is due to shock heat...

  9. White spot lesions: prevention and management during the orthodontic treatment.

    Science.gov (United States)

    Zabokova-Bilbilova, Efka; Popovska, Lidija; Kapusevska, Biljana; Stefanovska, Emilija

    2014-01-01

    The formation of white spot lesions, or enamel demineralization, around fixed orthodontic attachments is a common complication during and following fixed orthodontic treatment, which marks the result of a successfully completed case. This article is a contemporary review of the risk factors and preventive methods of these orthodontics scars. Preventive programmes must be emphasized to all orthodontic patients. The responsibility of an orthodontist is to minimize the risk of the patient having decalcification as a consequence of orthodontic treatment by educating and motivating the patients for excellent oral hygiene practice. Prophylaxis with topical fluoride application should be implemented: high-fluoride toothpastes, fluoride mouthwashes, gels and varnishes during and after the orthodontic treatment, especially for patients at high risk of caries.

  10. Late infiltration of post-orthodontic white spot lesions.

    Science.gov (United States)

    Neuhaus, Klaus W; Graf, Martina; Lussi, Adrian; Katsaros, Christos

    2010-11-01

    White spot lesion (WSL) infiltration has been recommended immediately after debonding of orthodontic brackets. It is however not clear if established inactive WSLs can also be masked through infiltration. Orthodontic treatment of a 19-year-old patient had to be terminated prematurely due to development of multiple WSLs of varying severity. Three months after debonding, the patient presented for lesion infiltration. After etching with 15% HCl gel and re-wetting of the dried surfaces it seemed that a good outcome could be expected. Lesion infiltration led to complete masking of less severe WSLs. The visual appearance of moderate and severe WSLs was improved but they were still visible after treatment. Inactive WSLs may not represent an increased caries risk, but patients are often bothered esthetically. Infiltration by repeated etching might be a viable approach even for inactive WSLs. Controlled clinical trials are needed to investigate the long-term performance of this technique.

  11. Integrating sustainable hunting in biodiversity protection in Central Africa: hot spots, weak spots, and strong spots.

    Directory of Open Access Journals (Sweden)

    John E Fa

    Full Text Available Wild animals are a primary source of protein (bushmeat for people living in or near tropical forests. Ideally, the effect of bushmeat harvests should be monitored closely by making regular estimates of offtake rate and size of stock available for exploitation. However, in practice, this is possible in very few situations because it requires both of these aspects to be readily measurable, and even in the best case, entails very considerable time and effort. As alternative, in this study, we use high-resolution, environmental favorability models for terrestrial mammals (N = 165 in Central Africa to map areas of high species richness (hot spots and hunting susceptibility. Favorability models distinguish localities with environmental conditions that favor the species' existence from those with detrimental characteristics for its presence. We develop an index for assessing Potential Hunting Sustainability (PHS of each species based on their ecological characteristics (population density, habitat breadth, rarity and vulnerability, weighted according to restrictive and permissive assumptions of how species' characteristics are combined. Species are classified into five main hunting sustainability classes using fuzzy logic. Using the accumulated favorability values of all species, and their PHS values, we finally identify weak spots, defined as high diversity regions of especial hunting vulnerability for wildlife, as well as strong spots, defined as high diversity areas of high hunting sustainability potential. Our study uses relatively simple models that employ easily obtainable data of a species' ecological characteristics to assess the impacts of hunting in tropical regions. It provides information for management by charting the geography of where species are more or less likely to be at risk of extinction from hunting.

  12. Integrating sustainable hunting in biodiversity protection in Central Africa: hot spots, weak spots, and strong spots.

    Science.gov (United States)

    Fa, John E; Olivero, Jesús; Farfán, Miguel Ángel; Márquez, Ana Luz; Vargas, Juan Mario; Real, Raimundo; Nasi, Robert

    2014-01-01

    Wild animals are a primary source of protein (bushmeat) for people living in or near tropical forests. Ideally, the effect of bushmeat harvests should be monitored closely by making regular estimates of offtake rate and size of stock available for exploitation. However, in practice, this is possible in very few situations because it requires both of these aspects to be readily measurable, and even in the best case, entails very considerable time and effort. As alternative, in this study, we use high-resolution, environmental favorability models for terrestrial mammals (N = 165) in Central Africa to map areas of high species richness (hot spots) and hunting susceptibility. Favorability models distinguish localities with environmental conditions that favor the species' existence from those with detrimental characteristics for its presence. We develop an index for assessing Potential Hunting Sustainability (PHS) of each species based on their ecological characteristics (population density, habitat breadth, rarity and vulnerability), weighted according to restrictive and permissive assumptions of how species' characteristics are combined. Species are classified into five main hunting sustainability classes using fuzzy logic. Using the accumulated favorability values of all species, and their PHS values, we finally identify weak spots, defined as high diversity regions of especial hunting vulnerability for wildlife, as well as strong spots, defined as high diversity areas of high hunting sustainability potential. Our study uses relatively simple models that employ easily obtainable data of a species' ecological characteristics to assess the impacts of hunting in tropical regions. It provides information for management by charting the geography of where species are more or less likely to be at risk of extinction from hunting.

  13. Integrating Sustainable Hunting in Biodiversity Protection in Central Africa: Hot Spots, Weak Spots, and Strong Spots

    Science.gov (United States)

    Fa, John E.; Olivero, Jesús; Farfán, Miguel Ángel; Márquez, Ana Luz; Vargas, Juan Mario; Real, Raimundo; Nasi, Robert

    2014-01-01

    Wild animals are a primary source of protein (bushmeat) for people living in or near tropical forests. Ideally, the effect of bushmeat harvests should be monitored closely by making regular estimates of offtake rate and size of stock available for exploitation. However, in practice, this is possible in very few situations because it requires both of these aspects to be readily measurable, and even in the best case, entails very considerable time and effort. As alternative, in this study, we use high-resolution, environmental favorability models for terrestrial mammals (N = 165) in Central Africa to map areas of high species richness (hot spots) and hunting susceptibility. Favorability models distinguish localities with environmental conditions that favor the species' existence from those with detrimental characteristics for its presence. We develop an index for assessing Potential Hunting Sustainability (PHS) of each species based on their ecological characteristics (population density, habitat breadth, rarity and vulnerability), weighted according to restrictive and permissive assumptions of how species' characteristics are combined. Species are classified into five main hunting sustainability classes using fuzzy logic. Using the accumulated favorability values of all species, and their PHS values, we finally identify weak spots, defined as high diversity regions of especial hunting vulnerability for wildlife, as well as strong spots, defined as high diversity areas of high hunting sustainability potential. Our study uses relatively simple models that employ easily obtainable data of a species' ecological characteristics to assess the impacts of hunting in tropical regions. It provides information for management by charting the geography of where species are more or less likely to be at risk of extinction from hunting. PMID:25372705

  14. Defects of mitochondrial DNA replication.

    Science.gov (United States)

    Copeland, William C

    2014-09-01

    Mitochondrial DNA is replicated by DNA polymerase γ in concert with accessory proteins such as the mitochondrial DNA helicase, single-stranded DNA binding protein, topoisomerase, and initiating factors. Defects in mitochondrial DNA replication or nucleotide metabolism can cause mitochondrial genetic diseases due to mitochondrial DNA deletions, point mutations, or depletion, which ultimately cause loss of oxidative phosphorylation. These genetic diseases include mitochondrial DNA depletion syndromes such as Alpers or early infantile hepatocerebral syndromes, and mitochondrial DNA deletion disorders, such as progressive external ophthalmoplegia, ataxia-neuropathy, or mitochondrial neurogastrointestinal encephalomyopathy. This review focuses on our current knowledge of genetic defects of mitochondrial DNA replication (POLG, POLG2, C10orf2, and MGME1) that cause instability of mitochondrial DNA and mitochondrial disease.

  15. Regulation of beta cell replication

    DEFF Research Database (Denmark)

    Lee, Ying C; Nielsen, Jens Høiriis

    2008-01-01

    Beta cell mass, at any given time, is governed by cell differentiation, neogenesis, increased or decreased cell size (cell hypertrophy or atrophy), cell death (apoptosis), and beta cell proliferation. Nutrients, hormones and growth factors coupled with their signalling intermediates have been...... suggested to play a role in beta cell mass regulation. In addition, genetic mouse model studies have indicated that cyclins and cyclin-dependent kinases that determine cell cycle progression are involved in beta cell replication, and more recently, menin in association with cyclin-dependent kinase...... inhibitors has been demonstrated to be important in beta cell growth. In this review, we consider and highlight some aspects of cell cycle regulation in relation to beta cell replication. The role of cell cycle regulation in beta cell replication is mostly from studies in rodent models, but whether...

  16. Shell Separation for Mirror Replication

    Science.gov (United States)

    1999-01-01

    NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery, and materials to replicate electro-formed nickel mirrors. Optics replication uses reusable forms, called mandrels, to make telescope mirrors ready for final finishing. MSFC optical physicist Bill Jones monitors a device used to chill a mandrel, causing it to shrink and separate from the telescope mirror without deforming the mirror's precisely curved surface.

  17. Personality and Academic Motivation: Replication, Extension, and Replication

    Science.gov (United States)

    Jones, Martin H.; McMichael, Stephanie N.

    2015-01-01

    Previous work examines the relationships between personality traits and intrinsic/extrinsic motivation. We replicate and extend previous work to examine how personality may relate to achievement goals, efficacious beliefs, and mindset about intelligence. Approximately 200 undergraduates responded to the survey with a 150 participants replicating…

  18. THE PROPERTIES OF CARRAGEENAN GELS

    Directory of Open Access Journals (Sweden)

    Grubnik I.M., Gladukh Ye.V., Chernyaev S.V.

    2012-04-01

    Full Text Available The article presents the results of studies on the functional properties of carrageenan, depending on the concentration of sodium chloride and xanthan in gels. It is established that the main factors in the syneresis of carrageenan gels are its concentration, the presence of ions and gums in solution. If using sodium chloride there is a change in the structure of mesh of the resulting gel, which leads to an increase in syneresis.

  19. A systematic approach to determine optimal composition of gel used in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Yuan-Jen [Department of Management Information Systems, Central Taiwan University of Science and Technology, Taichung, Taiwan (China); Institute of Biomedical Engineering and Material Science, Central Taiwan University of Science and Technology, Taichung, Taiwan (China); Hsieh, Bor-Tsung, E-mail: bthsieh@ctust.edu.tw [Department of Biomedical Imaging and Radiological Sciences, Central Taiwan University of Science and Technology, Taichung, Taiwan (China); Liang, Ji-An [Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan (China)

    2011-10-01

    The design of experiment was used to find the optimal composition of N-isopropyl acrylamide (NIPAM) gel. Optical computed tomography was used to scan the polymer gel dosimeter, which was irradiated from 0 to 20 Gy. The study was conducted following a statistical method using a two-level fractional factorial plan involving four variables (gelatin-5% and 6%, NIPAM-3% and 5%, Bis-2.5% and 3%, and THPC-5 and 10 mM). We produced three batches of gels of the same composition to replicate the experiments. Based on the statistical analysis, a regression model was built. The optimal gel composition for the dose range 0-15 Gy with linearity up to 1.000 is as follows: gelatin (5.67%), NIPAM (5%), Bis (2.56%), and THPC (10 mM). The dose response of the NIPAM polymer gel attains stability about 24 h after irradiation and remains stable up to 3 months.

  20. Gel polymer electrolytes for batteries

    Science.gov (United States)

    Balsara, Nitash Pervez; Eitouni, Hany Basam; Gur, Ilan; Singh, Mohit; Hudson, William

    2014-11-18

    Nanostructured gel polymer electrolytes that have both high ionic conductivity and high mechanical strength are disclosed. The electrolytes have at least two domains--one domain contains an ionically-conductive gel polymer and the other domain contains a rigid polymer that provides structure for the electrolyte. The domains are formed by block copolymers. The first block provides a polymer matrix that may or may not be conductive on by itself, but that can soak up a liquid electrolyte, thereby making a gel. An exemplary nanostructured gel polymer electrolyte has an ionic conductivity of at least 1.times.10.sup.-4 S cm.sup.-1 at 25.degree. C.

  1. Regulation of Replication Recovery and Genome Integrity

    DEFF Research Database (Denmark)

    Colding, Camilla Skettrup

    facilitate replication recovery after MMS-induced replication stress. Our data reveal that control of Mrc1 turnover through the interplay between posttranslational modifications and INQ localization adds another layer of regulation to the replication checkpoint. We also add replication recovery to the list...... is mediated by Mrc1, which ensures Mec1 presence at the stalled replication fork thus facilitating Rad53 phosphorylation. When replication can be resumed safely, the replication checkpoint is deactivated and replication forks restart. One mechanism for checkpoint deactivation is the ubiquitin......-targeted proteasomal degradation of Mrc1. In this study, we describe a novel nuclear structure, the intranuclear quality control compartment (INQ), which regulates protein turnover and is important for recovery after replication stress. We find that upon methyl methanesulfonate (MMS)-induced replication stress, INQ...

  2. Voyager 1 Red Spot Movie

    Science.gov (United States)

    2000-01-01

    This movie shows the portion of Jupiter around the Great Red Spot as it swirls through more than 60 Jupiter days. Notice the difference in speed and direction of the various zones of the atmosphere. The interaction of the atmospheric clouds and storm shows how dynamic the Jovian atmosphere is.As Voyager 1 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 66 images taken once every Jupiter rotation period (about 10 hours). This time-lapse movie uses images taken every time Jupiter longitude 68W passed under the spacecraft. These images were acquired in the Blue filter from Jan. 6 to Feb. 3 1979. The spacecraft flew from 58 million kilometers to 31 million kilometers from Jupiter during that time.This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  3. Ambystoma maculatum (spotted salamander). Reproduction

    Science.gov (United States)

    Glorioso, Brad M.; Waddle, Hardin; Hefner, Jeromi

    2012-01-01

    The Spotted Salamander is a wide-ranging salamander of the eastern United States that typically breeds in winter or early spring in ephemeral pools in lowland forests. Ambystoma maculatum is known to deposit 2-4 egg masses per year, each containing 1-250 eggs. As part of ongoing research into the ecology and reproductive biology of Spotted Salamanders in the Kisatchie District of Kisatchie National Forest in Natchitoches Parish, Louisiana, USA, we have been counting the number of embryos per egg mass. We captured seven female A. maculatum in a small pool, six of which were still gravid. We took standard measurements, including SVL, and then implanted a Passive Integrated Transponder (PIT tag) into each adult female as was the protocol. About an hour after processing these animals we marked new A. maculatum egg masses found in the same small pool using PVC pin flags pushed carefully through the outer jelly. We did not have enough time to process them that evening, and it was not until a few days later that we photographed those masses. We discovered that one of the masses contained a PIT tag in the outer jelly that corresponded to one of the six gravid females that were marked that same evening. To our knowledge, this is the first report of PIT tags being the means, albeit coincidentally, by which a particular egg mass of Ambystoma maculatum has been assigned to a particular female. For our purposes, losing the PIT tag from the adult female is counter to the goals of our study of this population, and we will no longer be implanting PIT tags into gravid females.

  4. Immunoreactivity and two-dimensional gel-electrophoresis characterization of Egyptian cobra venom proteome.

    Science.gov (United States)

    Almehdar, Hussein Abduelrahman; Adel-Sadek, Mahmoud Abass; Redwan, Elrashdy Moustafa

    2015-01-01

    The first and second (two) dimensional gel electrophoresis has a broad protein resolution power. It was used to separate and identify cobra venom proteome. The importance of characterizing venom proteins contents from the Egyptian elapidae, specifically neurotoxins, is based on the need to produce effective anti-venom. About 30-55distinct protein spots were identified on silver stained two-dimensional gels. Around two-thirds of the venom proteins displayed low a molecular weight and a migration into hydrophobic side. The venoms from Naja haja and Naja nigricollus showed 45-55 spots, while Walternnesia aegyptia had less (31-37) spots. The commercial prepared polyclonal antivenom had a strong signal for anionic and cationic venom protein spots with molecular weight 20-115 kDa. However, it showed weak or non immunoreactivity toward anionic low molecular weight spots (2.5-15 kDa). These results suggest the need to change the immunization schedule to include low molecular weight toxin-proteomes as separate dose or sequester injection.

  5. Hyperthermia stimulates HIV-1 replication.

    Directory of Open Access Journals (Sweden)

    Ferdinand Roesch

    Full Text Available HIV-infected individuals may experience fever episodes. Fever is an elevation of the body temperature accompanied by inflammation. It is usually beneficial for the host through enhancement of immunological defenses. In cultures, transient non-physiological heat shock (42-45°C and Heat Shock Proteins (HSPs modulate HIV-1 replication, through poorly defined mechanisms. The effect of physiological hyperthermia (38-40°C on HIV-1 infection has not been extensively investigated. Here, we show that culturing primary CD4+ T lymphocytes and cell lines at a fever-like temperature (39.5°C increased the efficiency of HIV-1 replication by 2 to 7 fold. Hyperthermia did not facilitate viral entry nor reverse transcription, but increased Tat transactivation of the LTR viral promoter. Hyperthermia also boosted HIV-1 reactivation in a model of latently-infected cells. By imaging HIV-1 transcription, we further show that Hsp90 co-localized with actively transcribing provirus, and this phenomenon was enhanced at 39.5°C. The Hsp90 inhibitor 17-AAG abrogated the increase of HIV-1 replication in hyperthermic cells. Altogether, our results indicate that fever may directly stimulate HIV-1 replication, in a process involving Hsp90 and facilitation of Tat-mediated LTR activity.

  6. Hyperthermia stimulates HIV-1 replication.

    Science.gov (United States)

    Roesch, Ferdinand; Meziane, Oussama; Kula, Anna; Nisole, Sébastien; Porrot, Françoise; Anderson, Ian; Mammano, Fabrizio; Fassati, Ariberto; Marcello, Alessandro; Benkirane, Monsef; Schwartz, Olivier

    2012-01-01

    HIV-infected individuals may experience fever episodes. Fever is an elevation of the body temperature accompanied by inflammation. It is usually beneficial for the host through enhancement of immunological defenses. In cultures, transient non-physiological heat shock (42-45°C) and Heat Shock Proteins (HSPs) modulate HIV-1 replication, through poorly defined mechanisms. The effect of physiological hyperthermia (38-40°C) on HIV-1 infection has not been extensively investigated. Here, we show that culturing primary CD4+ T lymphocytes and cell lines at a fever-like temperature (39.5°C) increased the efficiency of HIV-1 replication by 2 to 7 fold. Hyperthermia did not facilitate viral entry nor reverse transcription, but increased Tat transactivation of the LTR viral promoter. Hyperthermia also boosted HIV-1 reactivation in a model of latently-infected cells. By imaging HIV-1 transcription, we further show that Hsp90 co-localized with actively transcribing provirus, and this phenomenon was enhanced at 39.5°C. The Hsp90 inhibitor 17-AAG abrogated the increase of HIV-1 replication in hyperthermic cells. Altogether, our results indicate that fever may directly stimulate HIV-1 replication, in a process involving Hsp90 and facilitation of Tat-mediated LTR activity.

  7. Cellular Responses to Replication Problems

    NARCIS (Netherlands)

    M. Budzowska (Magdalena)

    2008-01-01

    textabstractDuring every S-phase cells need to duplicate their genomes so that both daughter cells inherit complete copies of genetic information. It is a tremendous task, given the large sizes of mammalian genomes and the required precision of DNA replication. A major threat to the accuracy and eff

  8. Covert Reinforcement: A Partial Replication.

    Science.gov (United States)

    Ripstra, Constance C.; And Others

    A partial replication of an investigation of the effect of covert reinforcement on a perceptual estimation task is described. The study was extended to include an extinction phase. There were five treatment groups: covert reinforcement, neutral scene reinforcement, noncontingent covert reinforcement, and two control groups. Each subject estimated…

  9. Crinivirus replication and host interactions

    Directory of Open Access Journals (Sweden)

    Zsofia A Kiss

    2013-05-01

    Full Text Available Criniviruses comprise one of the genera within the family Closteroviridae. Members in this family are restricted to the phloem and rely on whitefly vectors of the genera Bemisia and/or Trialeurodes for plant-to-plant transmission. All criniviruses have bipartite, positive-sense ssRNA genomes, although there is an unconfirmed report of one having a tripartite genome. Lettuce infectious yellows virus (LIYV is the type species of the genus, the best studied so far of the criniviruses and the first for which a reverse genetics system was available. LIYV RNA 1 encodes for proteins predicted to be involved in replication, and alone is competent for replication in protoplasts. Replication results in accumulation of cytoplasmic vesiculated membranous structures which are characteristic of most studied members of the Closteroviridae. These membranous structures, often referred to as BYV-type vesicles, are likely sites of RNA replication. LIYV RNA 2 is replicated in trans when co-infecting cells with RNA 1, but is temporally delayed relative to RNA1. Efficient RNA 2 replication also is dependent on the RNA 1-encoded RNA binding protein, P34. No LIYV RNA 2-encoded proteins have been shown to affect RNA replication, but at least four, CP, CPm, Hsp70h, and p59 are virion structural components and CPm is a determinant of whitefly transmissibility. Roles of other LIYV RNA 2-encoded proteins are largely as yet unknown, but P26 is a non-virion protein that accumulates in cells as characteristic plasmalemma deposits which in plants are localized within phloem parenchyma and companion cells over plasmodesmata connections to sieve elements. The two remaining crinivirus-conserved RNA 2-encoded proteins are P5 and P9. P5 is 39 amino acid protein and is encoded at the 5’ end of RNA 2 as ORF1 and is part of the hallmark closterovirus gene array. The orthologous gene in BYV has been shown to play a role in cell-to-cell movement and indicated to be localized to the

  10. Chromosome replication dynamics in the archaeon Sulfolobus acidocaldarius.

    Science.gov (United States)

    Duggin, Iain G; McCallum, Simon A; Bell, Stephen D

    2008-10-28

    The "baby machine" provides a means of generating synchronized cultures of minimally perturbed cells. We describe the use of this technique to establish the key cell-cycle parameters of hyperthermophilic archaea of the genus Sulfolobus. The 3 DNA replication origins of Sulfolobus acidocaldarius were mapped by 2D gel analysis to near 0 (oriC2), 579 (oriC1), and 1,197 kb (oriC3) on the 2,226-kb circular genome, and we present a direct demonstration of their activity within the first few minutes of a synchronous cell cycle. We also detected X-shaped DNA molecules at the origins in log-phase cells, but these were not directly associated with replication initiation or ongoing chromosome replication in synchronized cells. Whole-genome marker frequency analyses of both synchronous and log-phase cultures showed that origin utilization was close to 100% for all 3 origins per round of replication. However, oriC2 was activated slightly later on average compared with oriC1 and oriC3. The DNA replication forks moved bidirectionally away from each origin at approximately 88 bp per second in synchronous culture. Analysis of the 3 Orc1/Cdc6 initiator proteins showed a uniformity of cellular abundance and origin binding throughout the cell cycle. In contrast, although levels of the MCM helicase were constant across the cell cycle, its origin localization was regulated, because it was strongly enriched at all 3 origins in early S phase.

  11. Ambiguities in results obtained with 2D gel replicon mapping techniques

    NARCIS (Netherlands)

    Linskens, Maarten H.K.; Huberman, Joel A.

    1990-01-01

    Recently, two 2-dimensional (2D) gel techniques, termed neutral/neutral and neutral/alkaline, have been developed and employed to map replication origins in eukaryotic plasmids and chromosomal DNA. The neutral/neutral technique, which requires less DNA for analysis, has been preferentially used in r

  12. Hot Spot Removal System: System description

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    Hazardous wastes contaminated with radionuclides, chemicals, and explosives exist across the Department of Energy complex and need to be remediated due to environmental concerns. Currently, an opportunity is being developed to dramatically reduce remediation costs and to assist in the acceleration of schedules associated with these wastes by deploying a Hot Spot Removal System. Removing the hot spot from the waste site will remove risk driver(s) and enable another, more cost effective process/option/remedial alternative (i.e., capping) to be applied to the remainder of the site. The Hot Spot Removal System consists of a suite of technologies that will be utilized to locate and remove source terms. Components of the system can also be used in a variety of other cleanup activities. This Hot Spot Removal System Description document presents technologies that were considered for possible inclusion in the Hot Spot Removal System, technologies made available to the Hot Spot Removal System, industrial interest in the Hot Spot Removal System`s subsystems, the schedule required for the Hot Spot Removal System, the evaluation of the relevant technologies, and the recommendations for equipment and technologies as stated in the Plan section.

  13. Rocky Mountain spotted fever in children.

    Science.gov (United States)

    Woods, Charles R

    2013-04-01

    Rocky Mountain spotted fever is typically undifferentiated from many other infections in the first few days of illness. Treatment should not be delayed pending confirmation of infection when Rocky Mountain spotted fever is suspected. Doxycycline is the drug of choice even for infants and children less than 8 years old.

  14. The biology of the California spotted owl

    Science.gov (United States)

    R.J. Gutiérrez; Douglas J. Tempel; M. Zachariah Peery

    2017-01-01

    The spotted owl (Strix occidentalis) is one of the most studied raptors in the world (Lõmus 2004) because forest management throughout its range has the potential to negatively affect owl populations. Information on the California spotted owl (S. o. occidentalis) has been summarized in several literature reviews (e.g.,...

  15. Front blind spot crashes in Hong Kong.

    Science.gov (United States)

    Cheng, Yuk Ki; Wong, Koon Hung; Tao, Chi Hang; Tam, Cheok Ning; Tam, Yiu Yan; Tsang, Cheuk Nam

    2016-09-01

    In 2012-2014, our laboratory had investigated a total of 9 suspected front blind spot crashes, in which the medium and heavy goods vehicles pulled away from rest and rolled over the pedestrians, who were crossing immediately in front of the vehicles. The drivers alleged that they did not see any pedestrians through the windscreens or the front blind spot mirrors. Forensic assessment of the goods vehicles revealed the existence of front blind spot zones in 3 out of these 9 accident vehicles, which were attributed to the poor mirror adjustments or even the absence of a front blind spot mirror altogether. In view of this, a small survey was devised involving 20 randomly selected volunteers and their goods vehicles and 5 out of these vehicles had blind spots at the front. Additionally, a short questionnaire was conducted on these 20 professional lorry drivers and it was shown that most of them were not aware of the hazards of blind spots immediately in front of their vehicles, and many did not use the front blind spot mirrors properly. A simple procedure for quick measurements of the coverage of front blind spot mirrors using a coloured plastic mat with dimensional grids was also introduced and described in this paper.

  16. [Clitoris and G spot: an intimate affair].

    Science.gov (United States)

    Foldes, P; Buisson, O

    2007-01-01

    Ultrasonography is a good means for studying the clitoris and its relationship with the G spot. We used it to demonstrate that clitoral bodies have a descending movement and come close to the distal anterior vaginal wall during a voluntary or reflex contraction of levator ani muscles. This fact could explain the particular sensitivity of the G spot and its role in the orgasm.

  17. HotSpot Software Test Plan

    Energy Technology Data Exchange (ETDEWEB)

    Walker, H; Homann, S G

    2009-03-12

    This Software Test Plan (STP) describes the procedures used to verify and validate that the HotSpot Health Physics Codes meet the requirements of its user base, which includes: (1) Users of the PC version of HotSpot conducting consequence assessment, hazard assessment and safety analysis calculations; and (2) Users of the NARAC Web and iClient software tools, which allow users to run HotSpot for consequence assessment modeling. This plan is intended to meet Critical Recommendation 2 from the Software Evaluation of HotSpot and DOE Safety Software Toolbox Recommendation for inclusion of HotSpot in the Department of Energy (DOE) Safety Software Toolbox. These users and sponsors of the HotSpot software and the organizations they represent constitute the intended audience for this document. HotSpot software is maintained for the Department of Energy Office of Emergency Operations by the National Atmospheric Release Advisory Center (NARAC) at Lawrence Livermore National Laboratory (LLNL). An overview of HotSpot and NARAC are provided.

  18. HotSpot Software Configuration Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    Walker, H; Homann, S G

    2009-03-12

    This Software Configuration Management Plan (SCMP) describes the software configuration management procedures used to ensure that the HotSpot dispersion model meets the requirements of its user base, which includes: (1) Users of the PC version of HotSpot for consequence assessment, hazard assessment and safety analysis calculations; and (2) Users of the NARAC Web and iClient software tools, which allow users to run HotSpot for consequence assessment modeling These users and sponsors of the HotSpot software and the organizations they represent constitute the intended audience for this document. This plan is intended to meet Critical Recommendations 1 and 3 from the Software Evaluation of HotSpot and DOE Safety Software Toolbox Recommendation for inclusion of HotSpot in the Department of Energy (DOE) Safety Software Toolbox. HotSpot software is maintained for the Department of Energy Office of Emergency Operations by the National Atmospheric Release Advisory Center (NARAC) at Lawrence Livermore National Laboratory (LLNL). An overview of HotSpot and NARAC are provided.

  19. 7 CFR 28.415 - Low Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Low Middling Light Spotted Color. 28.415 Section 28... Spotted Color. Low Middling Light Spotted Color is color which in spot or color, or both, is between Low Middling Color and Low Middling Spotted Color....

  20. 7 CFR 28.412 - Strict Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Strict Middling Light Spotted Color. 28.412 Section 28... Light Spotted Color. Strict Middling Light Spotted Color is color which in spot or color, or both, is between Strict Middling Color and Strict Middling Spotted Color....

  1. 7 CFR 28.413 - Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Middling Light Spotted Color. 28.413 Section 28.413... Spotted Color. Middling Light Spotted Color is color which in spot or color, or both, is between Middling Color and Middling Spotted Color....

  2. 7 CFR 28.411 - Good Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Good Middling Light Spotted Color. 28.411 Section 28... Light Spotted Color. Good Middling Light Spotted Color is color which in spot or color, or both, is between Good Middling Color and Good Middling Spotted Color....

  3. Rheology and structure of milk protein gels

    NARCIS (Netherlands)

    Vliet, van T.; Lakemond, C.M.M.; Visschers, R.W.

    2004-01-01

    Recent studies on gel formation and rheology of milk gels are reviewed. A distinction is made between gels formed by aggregated casein, gels of `pure` whey proteins and gels in which both casein and whey proteins contribute to their properties. For casein' whey protein mixtures, it has been shown th

  4. Rheology and structure of milk protein gels

    NARCIS (Netherlands)

    Vliet, van T.; Lakemond, C.M.M.; Visschers, R.W.

    2004-01-01

    Recent studies on gel formation and rheology of milk gels are reviewed. A distinction is made between gels formed by aggregated casein, gels of `pure` whey proteins and gels in which both casein and whey proteins contribute to their properties. For casein' whey protein mixtures, it has been shown

  5. Nanocrystal/sol-gel nanocomposites

    Science.gov (United States)

    Petruska, Melissa A.; Klimov, Victor L.

    2007-06-05

    The present invention is directed to solid composites including colloidal nanocrystals within a sol-gel host or matrix and to processes of forming such solid composites. The present invention is further directed to alcohol soluble colloidal nanocrystals useful in formation of sol-gel based solid composites.

  6. Dermoscopy of black-spot poison ivy.

    Science.gov (United States)

    Rader, Ryan K; Mu, Ruipu; Shi, Honglan; Stoecker, William V; Hinton, Kristen A

    2012-10-15

    Black-spot poison ivy is an uncommon presentation of poison ivy (Toxicodendron) allergic contact dermatitis. A 78-year-old sought evaluation of a black spot present on her right hand amid pruritic vesicles. The presentation of a black spot on the skin in a clinical context suggesting poison ivy is indicative of black-spot poison ivy. Dermoscopy revealed a jagged, centrally homogeneous, dark brown lesion with a red rim. A skin sample was obtained and compared against a poison ivy standard using ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS). This finding confirmed the presence of multiple urushiol congeners in the skin sample. Black-spot poison ivy may be added to the list of diagnoses that show a specific dermoscopic pattern.

  7. Laser Spot Detection Based on Reaction Diffusion

    Science.gov (United States)

    Vázquez-Otero, Alejandro; Khikhlukha, Danila; Solano-Altamirano, J. M.; Dormido, Raquel; Duro, Natividad

    2016-01-01

    Center-location of a laser spot is a problem of interest when the laser is used for processing and performing measurements. Measurement quality depends on correctly determining the location of the laser spot. Hence, improving and proposing algorithms for the correct location of the spots are fundamental issues in laser-based measurements. In this paper we introduce a Reaction Diffusion (RD) system as the main computational framework for robustly finding laser spot centers. The method presented is compared with a conventional approach for locating laser spots, and the experimental results indicate that RD-based computation generates reliable and precise solutions. These results confirm the flexibility of the new computational paradigm based on RD systems for addressing problems that can be reduced to a set of geometric operations. PMID:26938537

  8. Laser Spot Detection Based on Reaction Diffusion

    Directory of Open Access Journals (Sweden)

    Alejandro Vázquez-Otero

    2016-03-01

    Full Text Available Center-location of a laser spot is a problem of interest when the laser is used for processing and performing measurements. Measurement quality depends on correctly determining the location of the laser spot. Hence, improving and proposing algorithms for the correct location of the spots are fundamental issues in laser-based measurements. In this paper we introduce a Reaction Diffusion (RD system as the main computational framework for robustly finding laser spot centers. The method presented is compared with a conventional approach for locating laser spots, and the experimental results indicate that RD-based computation generates reliable and precise solutions. These results confirm the flexibility of the new computational paradigm based on RD systems for addressing problems that can be reduced to a set of geometric operations.

  9. Replication-Uncoupled Histone Deposition during Adenovirus DNA Replication

    OpenAIRE

    Komatsu, Tetsuro; Nagata, Kyosuke

    2012-01-01

    In infected cells, the chromatin structure of the adenovirus genome DNA plays critical roles in its genome functions. Previously, we reported that in early phases of infection, incoming viral DNA is associated with both viral core protein VII and cellular histones. Here we show that in late phases of infection, newly synthesized viral DNA is also associated with histones. We also found that the knockdown of CAF-1, a histone chaperone that functions in the replication-coupled deposition of his...

  10. Forward and Spot Prices in Multi-Settlement Wholesale Electricity Markets

    Science.gov (United States)

    Larrieu, Jeremy

    In organized wholesale electricity markets, power is sold competitively in a multi-unit multi-settlement single-price auction comprised of a forward and a spot market. This dissertation attempts to understand the structure of the forward premium in these markets, and to identify the factors that may lead forward and spot prices to converge or diverge. These markets are unique in that the forward demand is price-sensitive, while spot residual demand is perfectly inelastic and must be met in full, a crucial design feature the literature often glosses over. An important contribution of this dissertation is the explicit modeling of each market separately in order to understand how generation and load choose to act in each one, and the consequences of these actions on equilibrium prices and quantities given that firms maximize joint profits over both markets. In the first essay, I construct a two-settlement model of electricity prices in which firms that own asymmetric capacity-constrained units facing convex costs compete to meet demand from consumers, first in quantities, then in prices. I show that the forward premium depends on the costliness of spot production relative to firms' ability to exercise market power by setting quantities in the forward market. In the second essay, I test the model from the first essay with unit-level capacity and marginal cost data from the California Independent System Operator (CAISO). I show that the model closely replicates observed price formation in the CAISO. In the third essay, I estimate a time series model of the CAISO forward premium in order to measure the impact that virtual bidding has had on forward and spot price convergence in California between April 2009 and March 2014. I find virtual bidding to have caused forward and spot prices to diverge due to the large number of market participants looking to hedge against - or speculate on - the occurrence of infrequent but large spot price spikes by placing virtual demand bids.

  11. Sucrose release from polysaccharide gels.

    Science.gov (United States)

    Nishinari, Katsuyoshi; Fang, Yapeng

    2016-05-18

    Sucrose release from polysaccharide gels has been studied extensively because it is expected to be useful in understanding flavour release from solid foods and to find a new processing method which produces more palatable and healthier foods. We provide an overview of the release of sucrose and other sugars from gels of agar and related polysaccharides. The addition of sucrose to agar solutions leads to the increase in transparency of the resulting gels and the decrease in syneresis, which is attributed to the decrease in mesh size in gels. The syneresis occurring in the quiescent condition and fluid release induced by compression is discussed. The relationship between the sugar release and the structural, rheological and thermal properties of gels is also discussed. Finally, the future research direction is proposed.

  12. Electrochemical Light-Emitting Gel

    Directory of Open Access Journals (Sweden)

    Nobuyuki Itoh

    2010-06-01

    Full Text Available Light-emitting gel, a gel state electroluminescence material, is reported. It is composed of a ruthenium complex as the emitter, an ionic liquid as the electrolyte, and oxide nanoparticles as the gelation filler. Emitted light was produced via electrogenerated chemiluminescence. The light-emitting gel operated at low voltage when an alternating current was passed through it, regardless of its structure, which is quite thick. The luminescence property of the gel is strongly affected by nanoparticle materials. TiO2 nanoparticles were a better gelation filler than silica or ZnO was, with respect to luminescence stability, thus indicating a catalytic effect. It is demonstrated that the light-emitting gel device, with quite a simple fabrication process, flashes with the application of voltage.

  13. REPLICATION TOOL AND METHOD OF PROVIDING A REPLICATION TOOL

    DEFF Research Database (Denmark)

    2016-01-01

    structured master surface (3a, 3b, 3c, 3d) having a lateral master pattern and a vertical master profile. The microscale structured master surface (3a, 3b, 3c, 3d) has been provided by localized pulsed laser treatment to generate microscale phase explosions. A method for producing a part with microscale......The invention relates to a replication tool (1, 1a, 1b) for producing a part (4) with a microscale textured replica surface (5a, 5b, 5c, 5d). The replication tool (1, 1a, 1b) comprises a tool surface (2a, 2b) defining a general shape of the item. The tool surface (2a, 2b) comprises a microscale...... energy directors on flange portions thereof uses the replication tool (1, 1a, 1b) to form an item (4) with a general shape as defined by the tool surface (2a, 2b). The formed item (4) comprises a microscale textured replica surface (5a, 5b, 5c, 5d) with a lateral arrangement of polydisperse microscale...

  14. Increase in local protein concentration by field-inversion gel electrophoresis

    Directory of Open Access Journals (Sweden)

    Paulus Aran

    2007-09-01

    Full Text Available Abstract Background Proteins that migrate through cross-linked polyacrylamide gels (PAGs under the influence of a constant electric field experience negative factors, such as diffusion and non-specific trapping in the gel matrix. These negative factors reduce protein concentrations within a defined gel volume with increasing migration distance and, therefore, decrease protein separation efficiency. Enhancement of protein separation efficiency was investigated by implementing pulsed field-inversion gel electrophoresis (FIGE. Results Separation of model protein species and large protein complexes was compared between FIGE and constant field electrophoresis (CFE in different percentages of PAGs. Band intensities of proteins in FIGE with appropriate ratios of forward and backward pulse times were superior to CFE despite longer running times. These results revealed an increase in band intensity per defined gel volume. A biphasic protein relative mobility shift was observed in percentages of PAGs up to 14%. However, the effect of FIGE on protein separation was stochastic at higher PAG percentage. Rat liver lysates subjected to FIGE in the second-dimension separation of two-dimensional polyarcylamide gel electrophoresis (2D PAGE showed a 20% increase in the number of discernible spots compared with CFE. Nine common spots from both FIGE and CFE were selected for peptide sequencing by mass spectrometry (MS, which revealed higher final ion scores of all nine protein spots from FIGE. Native protein complexes ranging from 800 kDa to larger than 2000 kDa became apparent using FIGE compared with CFE. Conclusion The present investigation suggests that FIGE under appropriate conditions improves protein separation efficiency during PAGE as a result of increased local protein concentration. FIGE can be implemented with minimal additional instrumentation in any laboratory setting. Despite the tradeoff of longer running times, FIGE can be a powerful protein

  15. Design and Optimization of the SPOT Primary Mirror Segment

    Science.gov (United States)

    Budinoff, Jason G.; Michaels, Gregory J.

    2005-01-01

    The 3m Spherical Primary Optical Telescope (SPOT) will utilize a single ring of 0.86111 point-to-point hexagonal mirror segments. The f2.85 spherical mirror blanks will be fabricated by the same replication process used for mass-produced commercial telescope mirrors. Diffraction-limited phasing will require segment-to-segment radius of curvature (ROC) variation of approx.1 micron. Low-cost, replicated segment ROC variations are estimated to be almost 1 mm, necessitating a method for segment ROC adjustment & matching. A mechanical architecture has been designed that allows segment ROC to be adjusted up to 400 microns while introducing a minimum figure error, allowing segment-to-segment ROC matching. A key feature of the architecture is the unique back profile of the mirror segments. The back profile of the mirror was developed with shape optimization in MSC.Nastran(TradeMark) using optical performance response equations written with SigFit. A candidate back profile was generated which minimized ROC-adjustment-induced surface error while meeting the constraints imposed by the fabrication method. Keywords: optimization, radius of curvature, Pyrex spherical mirror, Sigfit

  16. Replicator dynamics in value chains

    DEFF Research Database (Denmark)

    Cantner, Uwe; Savin, Ivan; Vannuccini, Simone

    2016-01-01

    The pure model of replicator dynamics though providing important insights in the evolution of markets has not found much of empirical support. This paper extends the model to the case of firms vertically integrated in value chains. We show that i) by taking value chains into account, the replicator...... dynamics may revert its effect. In these regressive developments of market selection, firms with low fitness expand because of being integrated with highly fit partners, and the other way around; ii) allowing partner's switching within a value chain illustrates that periods of instability in the early...... stage of industry life-cycle may be the result of an 'optimization' of partners within a value chain providing a novel and simple explanation to the evidence discussed by Mazzucato (1998); iii) there are distinct differences in the contribution to market selection between the layers of a value chain...

  17. In vivo dynamics of EBNA1-oriP interaction during latent and lytic replication of Epstein-Barr virus.

    Science.gov (United States)

    Daikoku, Tohru; Kudoh, Ayumi; Fujita, Masatoshi; Sugaya, Yutaka; Isomura, Hiroki; Tsurumi, Tatsuya

    2004-12-24

    The Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is required for maintenance of the viral genome DNA during the latent phase of EBV replication but continues to be synthesized after the induction of viral productive replication. An EBV genome-wide chromatin immunoprecipitation assay revealed that EBNA1 constantly binds to oriP of the EBV genome during not only latent but also lytic infection. Although the total levels of EBNA1 proved constant throughout the latter, the levels of the oriP-bound form were increased as lytic infection proceeded. EBV productive DNA replication occurs at discrete sites in nuclei, called replication compartments, where viral replication proteins are clustered. Confocal laser microscopic analyses revealed that whereas EBNA1 was distributed broadly in nuclei as fine punctate dots during the latent phase of infection, the protein became redistributed to the viral replication compartments and localized as distinct spots within and/or nearby the compartments after the induction of lytic replication. Taking these findings into consideration, oriP regions of the EBV genome might be organized by EBNA1 into replication domains that may set up scaffolding for lytic replication and transcription.

  18. A Novel Strategy for Characterization of Glycosylated Proteins Separated by Gel Electrophoresis

    DEFF Research Database (Denmark)

    Larsen, Martin; Skottrup, Peter; Enghild, Jan Johannes;

    at a sensitivity level comparable with state-of-the-art proteomics. Whereas techniques exist for characterization of high abundant glycoproteins, no single method is presently capable of providing information on both site occupancy and glycan structure on a single band or spot excised from an electrophoretic gel....... We present a new technique, which allows full characterization of low amounts of glycoproteins separated by gel electrophoresis. The method takes advantage of sequential specific and non-specific enzymatic treatment, followed by selective purification and characterization of the glycopeptides using...

  19. A Novel Strategy for Characterization of Glycosylated Proteins Separated by Gel Electrophoresis

    DEFF Research Database (Denmark)

    Larsen, Martin; Skottrup, Peter; Enghild, Jan Johannes

    . We present a new technique, which allows full characterization of low amounts of glycoproteins separated by gel electrophoresis. The method takes advantage of sequential specific and non-specific enzymatic treatment, followed by selective purification and characterization of the glycopeptides using...... at a sensitivity level comparable with state-of-the-art proteomics. Whereas techniques exist for characterization of high abundant glycoproteins, no single method is presently capable of providing information on both site occupancy and glycan structure on a single band or spot excised from an electrophoretic gel...

  20. Therapeutic targeting of replicative immortality

    OpenAIRE

    Yaswen, Paul; MacKenzie, Karen L.; Keith, W. Nicol; Hentosh, Patricia; Rodier, Francis; Zhu, Jiyue; Firestone, Gary L.; Matheu, Ander; Carnero, Amancio; Bilsland, Alan; Sundin, Tabetha; Honoki, Kanya; Fujii, Hiromasa; Georgakilas, Alexandros G.; Amedei, Amedeo

    2015-01-01

    One of the hallmarks of malignant cell populations is the ability to undergo continuous proliferation. This property allows clonal lineages to acquire sequential aberrations that can fuel increasingly autonomous growth, invasiveness, and therapeutic resistance. Innate cellular mechanisms have evolved to regulate replicative potential as a hedge against malignant progression. When activated in the absence of normal terminal differentiation cues, these mechanisms can result in a state of persis...

  1. Alphavirus polymerase and RNA replication.

    Science.gov (United States)

    Pietilä, Maija K; Hellström, Kirsi; Ahola, Tero

    2017-01-16

    Alphaviruses are typically arthropod-borne, and many are important pathogens such as chikungunya virus. Alphaviruses encode four nonstructural proteins (nsP1-4), initially produced as a polyprotein P1234. nsP4 is the core RNA-dependent RNA polymerase but all four nsPs are required for RNA synthesis. The early replication complex (RC) formed by the polyprotein P123 and nsP4 synthesizes minus RNA strands, and the late RC composed of fully processed nsP1-nsP4 is responsible for the production of genomic and subgenomic plus strands. Different parts of nsP4 recognize the promoters for minus and plus strands but the binding also requires the other nsPs. The alphavirus polymerase has been purified and is capable of de novo RNA synthesis only in the presence of the other nsPs. The purified nsP4 also has terminal adenylyltransferase activity, which may generate the poly(A) tail at the 3' end of the genome. Membrane association of the nsPs is vital for replication, and alphaviruses induce membrane invaginations called spherules, which form a microenvironment for RNA synthesis by concentrating replication components and protecting double-stranded RNA intermediates. The RCs isolated as crude membrane preparations are active in RNA synthesis in vitro, but high-resolution structure of the RC has not been achieved, and thus the arrangement of viral and possible host components remains unknown. For some alphaviruses, Ras-GTPase-activating protein (Src-homology 3 (SH3) domain)-binding proteins (G3BPs) and amphiphysins have been shown to be essential for RNA replication and are present in the RCs. Host factors offer an additional target for antivirals, as only few alphavirus polymerase inhibitors have been described.

  2. Superluminal Spot Pair Events in Astronomical Settings: Sweeping Beams

    CERN Document Server

    Nemiroff, Robert J

    2014-01-01

    Sweeping beams of light can cast spots moving with superluminal speeds across scattering surfaces. Such faster-than-light speeds are well-known phenomena that do not violate special relativity. It is shown here that under certain circumstances, superluminal spot pair creation and annihilation events can occur that provide unique information to observers. These spot pair events are {\\it not} particle pair events -- they are the sudden creation or annihilation of a pair of relatively illuminated spots on a scattering surface. Real spot pair illumination events occur unambiguously on the scattering surface when spot speeds diverge, while virtual spot pair events are observer dependent and perceived only when real spot radial speeds cross the speed of light. Specifically, a virtual spot pair creation event will be observed when a real spot's speed toward the observer drops below $c$, while a virtual spot pair annihilation event will be observed when a real spot's radial speed away from the observer rises above $c...

  3. Dynamic replication of Web contents

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The phenomenal growth of the World Wide Web has brought huge increase in the traffic to the popular web sites.Long delays and denial of service experienced by the end-users,especially during the peak hours,continues to be the common problem while accessing popular sites.Replicating some of the objects at multiple sites in a distributed web-server environment is one of the possible solutions to improve the response time/Iatency. The decision of what and where to replicate requires solving a constraint optimization problem,which is NP-complete in general.In this paper, we consider the problem of placing copies of objects in a distributed web server system to minimize the cost of serving read and write requests when the web servers have Iimited storage capacity.We formulate the problem as a 0-1 optimization problem and present a polynomial time greedy algorithm with backtracking to dynamically replicate objects at the appropriate sites to minimize a cost function.To reduce the solution search space,we present necessary condi tions for a site to have a replica of an object jn order to minimize the cost function We present simulation resuIts for a variety of problems to illustrate the accuracy and efficiency of the proposed algorithms and compare them with those of some well-known algorithms.The simulation resuIts demonstrate the superiority of the proposed algorithms.

  4. sol-gel

    Directory of Open Access Journals (Sweden)

    Humberto A. Monreal

    2005-01-01

    Full Text Available En este trabajo sintetizamos nanocilindros de dióxido de titanio de 30 a 400 nm por medio de ADN del plásmido pBR322 de 4,362 pares de bases y el uso de isopropóxido de titanio como precursor por medio del proceso sol-gel. Los geles resultantes fueron calcinados y los polvos caracterizados por medio de Microscopio Electrónico de Barrido (MEB, Espectroscopía de Energía Dispersiva, Microscopio Electrónico de Transmisión (MET y Difracción de Rayos X. Los resultados muestran que la síntesis in vitro de nanorods en presencia de ADN, puede ser activada. Muchas otras moléculas sintéticas pueden producirse por medio del uso de sistemas orgánicos, es así como reportamos la síntesis de híbridos hechos de ácidos nucleicos en materiales inorgánicos que pueden tener diversas aplicaciones en sistemas catalíticos, biomateriales y materiales nanoestructurados.

  5. DNA Replication Dynamics of the GGGGCC Repeat of the C9orf72 Gene.

    Science.gov (United States)

    Thys, Ryan Griffin; Wang, Yuh-Hwa

    2015-11-27

    DNA has the ability to form a variety of secondary structures in addition to the normal B-form DNA, including hairpins and quadruplexes. These structures are implicated in a number of neurological diseases and cancer. Expansion of a GGGGCC repeat located at C9orf72 is associated with familial amyotrophic lateral sclerosis and frontotemporal dementia. This repeat expands from two to 24 copies in normal individuals to several hundreds or thousands of repeats in individuals with the disease. Biochemical studies have demonstrated that as little as four repeats have the ability to form a stable DNA secondary structure known as a G-quadruplex. Quadruplex structures have the ability to disrupt normal DNA processes such as DNA replication and transcription. Here we examine the role of GGGGCC repeat length and orientation on DNA replication using an SV40 replication system in human cells. Replication through GGGGCC repeats leads to a decrease in overall replication efficiency and an increase in instability in a length-dependent manner. Both repeat expansions and contractions are observed, and replication orientation is found to influence the propensity for expansions or contractions. The presence of replication stress, such as low-dose aphidicolin, diminishes replication efficiency but has no effect on instability. Two-dimensional gel electrophoresis analysis demonstrates a replication stall with as few as 20 GGGGCC repeats. These results suggest that replication of the GGGGCC repeat at C9orf72 is perturbed by the presence of expanded repeats, which has the potential to result in further expansion, leading to disease.

  6. Mechanical Failure in Colloidal Gels

    Science.gov (United States)

    Kodger, Thomas Edward

    When colloidal particles in a dispersion are made attractive, they aggregate into fractal clusters which grow to form a space-spanning network, or gel, even at low volume fractions. These gels are crucial to the rheological behavior of many personal care, food products and dispersion-based paints. The mechanical stability of these products relies on the stability of the colloidal gel network which acts as a scaffold to provide these products with desired mechanical properties and to prevent gravitational sedimentation of the dispersed components. Understanding the mechanical stability of such colloidal gels is thus of crucial importance to predict and control the properties of many soft solids. Once a colloidal gel forms, the heterogeneous structure bonded through weak physical interactions, is immediately subject to body forces, such as gravity, surface forces, such as adhesion to a container walls and shear forces; the interplay of these forces acting on the gel determines its stability. Even in the absence of external stresses, colloidal gels undergo internal rearrangements within the network that may cause the network structure to evolve gradually, in processes known as aging or coarsening or fail catastrophically, in a mechanical instability known as syneresis. Studying gel stability in the laboratory requires model colloidal system which may be tuned to eliminate these body or endogenous forces systematically. Using existing chemistry, I developed several systems to study delayed yielding by eliminating gravitational stresses through density matching and cyclic heating to induce attraction; and to study syneresis by eliminating adhesion to the container walls, altering the contact forces between colloids, and again, inducing gelation through heating. These results elucidate the varied yet concomitant mechanisms by which colloidal gels may locally or globally yield, but then reform due to the nature of the physical, or non-covalent, interactions which form

  7. Surface grafted chitosan gels. Part II. Gel formation and characterization

    DEFF Research Database (Denmark)

    Liu, Chao; Thormann, Esben; Claesson, Per M.

    2014-01-01

    Responsive biomaterial hydrogels attract significant attention due to their biocompatibility and degradability. In order to make chitosan based gels, we first graft one layer of chitosan to silica, and then build a chitosan/poly(acrylic acid) multilayer using the layer-by-layer approach. After...... cross-linking the chitosan present in the polyelectrolyte multilayer, poly(acrylic acid) is partly removed by exposing the multilayer structure to a concentrated carbonate buffer solution at a high pH, leaving a surface-grafted cross-linked gel. Chemical cross-linking enhances the gel stability against......-linking density. The amount of poly(acrylic acid) trapped inside the surface grafted films was found to decrease with decreasing cross-linking density, as confirmed in situ using TIRR, and ex situ by Fourier transform infrared (FTIR) measurements on dried films. The responsiveness of the chitosan-based gels...

  8. CMB Cold Spot from Inflationary Feature Scattering

    CERN Document Server

    Wang, Yi

    2015-01-01

    We propose a "feature-scattering" mechanism to explain the cosmic microwave background cold spot seen from {\\it WMAP} and {\\it Planck} maps. If there are hidden features in the potential of multi-field inflation, the inflationary trajectory can be scattered by such features. The scattering is controlled by the amount of isocurvature fluctuations, and thus can be considered as a mechanism to convert isocurvature fluctuations into curvature fluctuations. This mechanism predicts localized cold spots (instead of hot ones) on the CMB. In addition, it may also bridge a connection between the cold spot and a dip on the CMB power spectrum at $\\ell \\sim 20$.

  9. Evaluating replicability of laboratory experiments in economics.

    Science.gov (United States)

    Camerer, Colin F; Dreber, Anna; Forsell, Eskil; Ho, Teck-Hua; Huber, Jürgen; Johannesson, Magnus; Kirchler, Michael; Almenberg, Johan; Altmejd, Adam; Chan, Taizan; Heikensten, Emma; Holzmeister, Felix; Imai, Taisuke; Isaksson, Siri; Nave, Gideon; Pfeiffer, Thomas; Razen, Michael; Wu, Hang

    2016-03-25

    The replicability of some scientific findings has recently been called into question. To contribute data about replicability in economics, we replicated 18 studies published in the American Economic Review and the Quarterly Journal of Economics between 2011 and 2014. All of these replications followed predefined analysis plans that were made publicly available beforehand, and they all have a statistical power of at least 90% to detect the original effect size at the 5% significance level. We found a significant effect in the same direction as in the original study for 11 replications (61%); on average, the replicated effect size is 66% of the original. The replicability rate varies between 67% and 78% for four additional replicability indicators, including a prediction market measure of peer beliefs.

  10. Proteins pattern alteration in AZT-treated K562 cells detected by two-dimensional gel electrophoresis and peptide mass fingerprinting

    Directory of Open Access Journals (Sweden)

    Mignogna Giuseppina

    2006-03-01

    Full Text Available Abstract In this study we report the effect of AZT on the whole protein expression profile both in the control and the AZT-treated K562 cells, evidenced by two-dimensional gel electrophoresis and peptide mass fingerprinting analysis. Two-dimensional gels computer digital image analysis showed two spots that appeared up-regulated in AZT-treated cells and one spot present only in the drug exposed samples. Upon extraction and analysis by peptide mass fingerprinting, the first two spots were identified as PDI-A3 and stathmin, while the third one was proved to be NDPK-A. Conversely, two protein spots were present only in the untreated K562 cells, and were identified as SOD1 and HSP-60, respectively.

  11. Differential analysis of two-dimensional gel electrophoresis profiles of spermatozoa protein in human normal motility sperm and idiopathic asthenospermia

    Institute of Scientific and Technical Information of China (English)

    SHEN Shu-lin; HE Da-lin; LUO Yong; NING Liang

    2006-01-01

    Objective: To evaluate the application of two-dimensional electrophoresis in the research of differentially expressed proteins in the human asthenospermia. Methods: Two-dimensional gel electrophoresis was performed on 4 normal sperm samples from healthy men and 4 sperm samples from 4 asthenospermia patients. After silver staining, the differential expression proteins were analyzed by PDQuest 2D analysis software. Results: Six differential protein spots were identified. Four spots showed increased expression in the control gels compared with the patient gels. Conclusion: The protein profiles of differential expression between the normal spermatozoa and idiopathic asthenospermia were established and some differential proteins were found. The data of this study would establish the better fundament for further isolation and identification of differentially expressed proteins in human asthenospermia sperm.

  12. Fragmentation of bacteriophage S13 replicative from DNA by restriction endonucleases from Hemophilus influenzae and Hemophilus aegyptius.

    NARCIS (Netherlands)

    F.G. Grosveld (Frank); K.M. Ojamaa; J.H. Spencer

    1976-01-01

    textabstractThe restriction enzymes Hind from Hemophilus influenzae and HaeIII from Hemophilus aegyptius cleave bacteriophage S13 replicative form (RF) DNA into 13 and 10 specific fragments, respectively. The sizes of these fragments were estimated by gel electrophoresis, electron microscopy, and py

  13. Adenovirus sequences required for replication in vivo.

    OpenAIRE

    Wang, K.; Pearson, G D

    1985-01-01

    We have studied the in vivo replication properties of plasmids carrying deletion mutations within cloned adenovirus terminal sequences. Deletion mapping located the adenovirus DNA replication origin entirely within the first 67 bp of the adenovirus inverted terminal repeat. This region could be further subdivided into two functional domains: a minimal replication origin and an adjacent auxillary region which boosted the efficiency of replication by more than 100-fold. The minimal origin occup...

  14. Pinite-cordierite from spotted slate of the Brajkovac contact metamorphic aureole (Dudovica locality, central Serbia

    Directory of Open Access Journals (Sweden)

    Vasković Nada

    2013-01-01

    Full Text Available The Paleozoic very low to low-grade metamorphic rocks of the Bukulja-Lazarevac Unit designated as Drina, Golija and Birač formations are contact metamorphosed by the intrusion of the Tertiary Brajkovac granodiorite into spotted slates and hornfelses. In some parts, they are slightly migmatized at the contact. In addition to their outcrops found at the western, eastern and northern parts of the formation, these rocks are also found in boreholes near Dudovica at about 8 km south-west from the pluton. There, at a depth of 110 m, the spotted slates comprise oval to ellipsoid pinite-rich spots which can be regarded as incipient cordierite porphyroblasts (up to 5 mm in diameter overgrowing the existing regional foliation. They are composed of cryptocrystalline mixture of a very fine sericitic material ± light glassy orange „film“ (some kind of an amorphous gel-like material often mixed with limonite matter and are abundant in inclusions: minute quartz and dusty ore minerals (magnetite prevail. In addition, within some spots an increased number of xenotime and monazite inclusions are noted. Minute flakes of neobiotite are formed at the expense of quartz-sericite-chlorite matrix. The secondary chlorite occurring as overgrowths on pinite-cordierite spots shows variable composition (brunsvigite to diabandite. The Mg/Fe+Mg ratio of cryptocrystalline pinitic mixture ranges from 0.14-0.67. The Si vs AlIV+AlVI relations deviate from the ideal muscovite-phengite join due to Tschermak substitution towards chloritic composition or a more complex mixture, including clay minerals (which reflected a decrease of Altot and Si with increase of Fe2+. Obtained data indicates that the cordierite-pinite spots can be related to contact metamorphic processes that occurred within the temperature range 300-450°C. [Projekat Ministarstva nauke Republike Srbije, br. 176019 i br. 176016

  15. Replication Origin Specification Gets a Push.

    Science.gov (United States)

    Plosky, Brian S

    2015-12-03

    During the gap between G1 and S phases when replication origins are licensed and fired, it is possible that DNA translocases could disrupt pre-replicative complexes (pre-RCs). In this issue of Molecular Cell, Gros et al. (2015) find that pre-RCs can be pushed along DNA and retain the ability to support replication.

  16. Exploiting replicative stress to treat cancer

    DEFF Research Database (Denmark)

    Dobbelstein, Matthias; Sørensen, Claus Storgaard

    2015-01-01

    DNA replication in cancer cells is accompanied by stalling and collapse of the replication fork and signalling in response to DNA damage and/or premature mitosis; these processes are collectively known as 'replicative stress'. Progress is being made to increase our understanding of the mechanisms...

  17. Fluoride Rinses, Gels and Foams

    DEFF Research Database (Denmark)

    Twetman, Svante; Keller, Mette K

    2016-01-01

    AIM: The aim of this conference paper was to systematically review the quality of evidence and summarize the findings of clinical trials published after 2002 using fluoride mouth rinses, fluoride gels or foams for the prevention of dental caries. METHODS: Relevant papers were selected after...... (6 on fluoride mouth rinse, 10 on fluoride gel and 3 on fluoride foam); 6 had a low risk of bias while 2 had a moderate risk. All fluoride measures appeared to be beneficial in preventing crown caries and reversing root caries, but the quality of evidence was graded as low for fluoride mouth rinse......, moderate for fluoride gel and very low for acidulated fluoride foam. No conclusions could be drawn on the cost-effectiveness. CONCLUSIONS: This review, covering the recent decade, has further substantiated the evidence for a caries-preventive effect of fluoride mouth rinse, fluoride gel and foam...

  18. Colloidal gels: Clay goes patchy

    Science.gov (United States)

    Kegel, Willem K.; Lekkerkerker, Henk N. W.

    2011-01-01

    Empty liquids and equilibrium gels have so far been only theoretical possibilities, predicted for colloids with patchy interactions. But evidence of both has now been found in Laponite, a widely studied clay.

  19. Proteomic Analysis of Bovine Pregnancy-specific Serum Proteins by 2D Fluorescence Difference Gel Electrophoresis

    Directory of Open Access Journals (Sweden)

    Jae Eun Lee

    2015-06-01

    Full Text Available Two dimensional-fluorescence difference gel electrophoresis (2D DIGE is an emerging technique for comparative proteomics, which improves the reproducibility and reliability of differential protein expression analysis between samples. The purpose of this study was to investigate bovine pregnancy-specific proteins in the proteome between bovine pregnant and non-pregnant serum using DIGE technique. Serums of 2 pregnant Holstein dairy cattle at day 21 after artificial insemination and those of 2 non-pregnant were used in this study. The pre-electrophoretic labeling of pregnant and non-pregnant serum proteins were mixed with Cy3 and Cy5 fluorescent dyes, respectively, and an internal standard was labeled with Cy2. Labeled proteins with Cy2, Cy3, and Cy5 were separated together in a single gel, and then were detected by fluorescence image analyzer. The 2D DIGE method using fluorescence CyDye DIGE flour had higher sensitivity than conventional 2D gel electrophoresis, and showed reproducible results. Approximately 1,500 protein spots were detected by 2D DIGE. Several proteins showed a more than 1.5-fold up and down regulation between non-pregnant and pregnant serum proteins. The differentially expressed proteins were identified by MALDI-TOF mass spectrometer. A total 16 protein spots were detected to regulate differentially in the pregnant serum, among which 7 spots were up-regulated proteins such as conglutinin precursor, modified bovine fibrinogen and IgG1, and 6 spots were down-regulated proteins such as hemoglobin, complement component 3, bovine fibrinogen and IgG2a three spots were not identified. The identified proteins demonstrate that early pregnant bovine serum may have several pregnancy-specific proteins, and these could be a valuable information for the development of pregnancy-diagnostic markers in early pregnancy bovine serum.

  20. Proteomic Analysis of Bovine Pregnancy-specific Serum Proteins by 2D Fluorescence Difference Gel Electrophoresis

    Science.gov (United States)

    Lee, Jae Eun; Lee, Jae Young; Kim, Hong Rye; Shin, Hyun Young; Lin, Tao; Jin, Dong Il

    2015-01-01

    Two dimensional-fluorescence difference gel electrophoresis (2D DIGE) is an emerging technique for comparative proteomics, which improves the reproducibility and reliability of differential protein expression analysis between samples. The purpose of this study was to investigate bovine pregnancy-specific proteins in the proteome between bovine pregnant and non-pregnant serum using DIGE technique. Serums of 2 pregnant Holstein dairy cattle at day 21 after artificial insemination and those of 2 non-pregnant were used in this study. The pre-electrophoretic labeling of pregnant and non-pregnant serum proteins were mixed with Cy3 and Cy5 fluorescent dyes, respectively, and an internal standard was labeled with Cy2. Labeled proteins with Cy2, Cy3, and Cy5 were separated together in a single gel, and then were detected by fluorescence image analyzer. The 2D DIGE method using fluorescence CyDye DIGE flour had higher sensitivity than conventional 2D gel electrophoresis, and showed reproducible results. Approximately 1,500 protein spots were detected by 2D DIGE. Several proteins showed a more than 1.5-fold up and down regulation between non-pregnant and pregnant serum proteins. The differentially expressed proteins were identified by MALDI-TOF mass spectrometer. A total 16 protein spots were detected to regulate differentially in the pregnant serum, among which 7 spots were up-regulated proteins such as conglutinin precursor, modified bovine fibrinogen and IgG1, and 6 spots were down-regulated proteins such as hemoglobin, complement component 3, bovine fibrinogen and IgG2a three spots were not identified. The identified proteins demonstrate that early pregnant bovine serum may have several pregnancy-specific proteins, and these could be a valuable information for the development of pregnancy-diagnostic markers in early pregnancy bovine serum. PMID:25925056

  1. Experimental and simulated strength of spot welds

    DEFF Research Database (Denmark)

    Nielsen, Chris Valentin; Bennedbæk, Rune A.K.; Larsen, Morten B.

    2014-01-01

    Weld strength testing of single spots in DP600 steel is presented for the three typical testing procedures, i.e. tensile-shear, cross-tension and peel testing. Spot welds are performed at two sets of welding parameters and strength testing under these conditions is presented by load-elongation cu......Weld strength testing of single spots in DP600 steel is presented for the three typical testing procedures, i.e. tensile-shear, cross-tension and peel testing. Spot welds are performed at two sets of welding parameters and strength testing under these conditions is presented by load......-elongation curves revealing the maximum load and the elongation at break. Welding and strength testing is simulated by SORPAS® 3D, which allows the two processes to be prepared in a combined simulation, such that the simulated welding properties are naturally applied to the simulation of strength testing. Besides...

  2. How Many Spots Does a Cheetah Have?

    Science.gov (United States)

    Reed, Kristine M.

    2000-01-01

    Describes first grade students' mathematical investigation of the number of spots on a cheetah. The exploration of counting and estimation strategies that grew from the investigation gives evidence that mathematicians come in all ages. (ASK)

  3. Tissue Testing Can Spot Zika at Birth

    Science.gov (United States)

    ... 166828.html Tissue Testing Can Spot Zika at Birth: CDC Just 1 in 10 possible cases actually ... havoc on babies, but diagnosing the infection before birth remains a challenge. Now, there's some good news: ...

  4. Scientists Spot Genes Behind Crohn's, Ulcerative Colitis

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_166957.html Scientists Spot Genes Behind Crohn's, Ulcerative Colitis Large study finds key ... Researchers say they've come closer to pinpointing genes linked with inflammatory bowel diseases such as Crohn's ...

  5. SPOT Controlled Image Base 10 meter

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — SPOT Controlled Image Base 10 meter (CIB-10) is a collection of orthorectified panchromatic (grayscale) images. The data were acquired between 1986 and 1993 by the...

  6. A comprehensive overview of the Cold Spot

    CERN Document Server

    Vielva, P

    2010-01-01

    The report of a significant deviation of the CMB temperature anisotropies distribution from Gaussianity (soon after the public release of the WMAP data in 2003) has become one of the most solid WMAP anomalies. This detection grounds on an excess of the kurtosis of the Spherical Mexican Hat Wavelet coefficients at scales of around 10 degrees. At these scales, a prominent feature --located in the southern Galactic hemisphere-- was highlighted from the rest of the SMHW coefficients: the Cold Spot. This article presents a comprehensive overview related to the study of the Cold Spot, paying attention to the non-Gaussianity detection methods, the morphological characteristics of the Cold Spot, and the possible sources studied in the literature to explain its nature. Special emphasis is made on the Cold Spot compatibility with a cosmic texture, commenting on future tests that would help to give support or discard this hypothesis.

  7. SPOT Controlled Image Base 10 meter

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — SPOT Controlled Image Base 10 meter (CIB-10) is a collection of orthorectified panchromatic (grayscale) images. The data were acquired between 1986 and 1993 by the...

  8. How Many Spots Does a Cheetah Have?

    Science.gov (United States)

    Reed, Kristine M.

    2000-01-01

    Describes first grade students' mathematical investigation of the number of spots on a cheetah. The exploration of counting and estimation strategies that grew from the investigation gives evidence that mathematicians come in all ages. (ASK)

  9. Measuring microfocus focal spots using digital radiography

    Energy Technology Data Exchange (ETDEWEB)

    Fry, David A [Los Alamos National Laboratory

    2009-01-01

    Measurement of microfocus spot size can be important for several reasons: (1) Quality assurance during manufacture of microfocus tubes; (2) Tracking performance and stability of microfocus tubes; (3) Determining magnification (especially important for digital radiography where the native spatial resolution of the digital system is not adequate for the application); (4) Knowledge of unsharpness from the focal spot alone. The European Standard EN 12543-5 is based on a simple geometrical method of calculating focal spot size from unsharpness of high magnification film radiographs. When determining microfocus focal spot dimensions using unsharpness measurements both signal-to-noise (SNR) and magnification can be important. There is a maximum accuracy that is a function of SNR and therefore an optimal magnification. Greater than optimal magnification can be used but it will not increase accuracy.

  10. HST image of Saturn's 'white spot'

    Science.gov (United States)

    1990-01-01

    Saturn's 'white spot' or cloud believed to be ammonia ice crystals recorded by the Hubble Space Telescope (HST) planetary camera in blue and infrared light. HST data was computer-processed improving the image sharpness.

  11. Silica reinforced triblock copolymer gels

    DEFF Research Database (Denmark)

    Theunissen, E.; Overbergh, N.; Reynaers, H.

    2004-01-01

    The effect of silica and polymer coated silica particles as reinforcing agents on the structural and mechanical properties of polystyrene-poly(ethylene/butylene)-polystyrene (PS-PEB-PS) triblock gel has been investigated. Different types of chemically modified silica have been compared in order...... a viscoclastic rubber to a plastic fluid and from a plastic fluid to a viscoelastic liquid are shifted to more elevated temperatures when silica is added to the triblock copolymer gel. (C) 2004 Elsevier Ltd. All rights reserved....

  12. White-spot disease of salmon fry

    Science.gov (United States)

    Mazuranich, J.J.; Nielson, W.E.

    1959-01-01

     White-spot disease, sometimes referred to as coagulated-yolk disease, has been associated with excessive mortalities occurring among the fry and early fingerling stages of the fall chinook salmon (Oncorhynchus tshawytacha) at the U.S. Fish-Cultural Stations at Carson, Cook, Underwood, and Willard, Washington. This disease of eggs and fry should not be confused with the "white-spot" infection that is caused in fingerlings by members of the protozoan genus Ichthyophthirius.

  13. Trace Detection of RDX, HMX and PETN Explosives Using a Fluorescence Spot Sensor

    Science.gov (United States)

    Wang, Chen; Huang, Helin; Bunes, Benjamin R.; Wu, Na; Xu, Miao; Yang, Xiaomei; Yu, Li; Zang, Ling

    2016-05-01

    1,3,5-trinitroperhydro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and pentaerythritol tetranitrate (PETN), the major components in plastic explosives, pose a significant threat to public safety. A quick, sensitive, and low-cost detection method for these non-volatile explosives is eagerly demanded. Here we present a fluo-spot approach, which can be employed for in situ detection of trace amount of explosives. The sensor molecule is a charge-transfer fluorophore, DCM, which is strongly fluorescent in its pristine state, but non-fluorescent after the quick reaction with NO2· (or NO2+) generated from the UV photolysis of RDX, HMX (or PETN). When fabricated within silica gel TLC plate, the fluo-spot sensor features high sensitivity owing to the large surface area and porous structure of the substrate. The sensor reaction mechanism was verified by various experimental characterizations, including chromatography, UV-Vis absorption and fluorescence spectroscopy, MS and 1H NMR spectrometry. The fluo-spot also demonstrated high selectivity towards RDX, HMX and PETN, as no significant fluorescence quenching was observed for other chemical compounds including common nitro-aromatic explosives and inorganic oxidative compounds. The DCM sensor can also be used as an economical spray kit to directly spot the explosives by naked eyes, implying great potential for quick, low-cost trace explosives detection.

  14. Surface grafted chitosan gels. Part II. Gel formation and characterization.

    Science.gov (United States)

    Liu, Chao; Thormann, Esben; Claesson, Per M; Tyrode, Eric

    2014-07-29

    Responsive biomaterial hydrogels attract significant attention due to their biocompatibility and degradability. In order to make chitosan based gels, we first graft one layer of chitosan to silica, and then build a chitosan/poly(acrylic acid) multilayer using the layer-by-layer approach. After cross-linking the chitosan present in the polyelectrolyte multilayer, poly(acrylic acid) is partly removed by exposing the multilayer structure to a concentrated carbonate buffer solution at a high pH, leaving a surface-grafted cross-linked gel. Chemical cross-linking enhances the gel stability against detachment and decomposition. The chemical reaction between gluteraldehyde, the cross-linking agent, and chitosan was followed in situ using total internal reflection Raman (TIRR) spectroscopy, which provided a molecular insight into the complex reaction mechanism, as well as the means to quantify the cross-linking density. The amount of poly(acrylic acid) trapped inside the surface grafted films was found to decrease with decreasing cross-linking density, as confirmed in situ using TIRR, and ex situ by Fourier transform infrared (FTIR) measurements on dried films. The responsiveness of the chitosan-based gels with respect to pH changes was probed by quartz crystal microbalance with dissipation (QCM-D) and TIRR. Highly cross-linked gels show a small and fully reversible behavior when the solution pH is switched between pH 2.7 and 5.7. In contrast, low cross-linked gels are more responsive to pH changes, but the response is fully reversible only after the first exposure to the acidic solution, once an internal restructuring of the gel has taken place. Two distinct pKa's for both chitosan and poly(acrylic acid), were determined for the cross-linked structure using TIRR. They are associated with populations of chargeable groups displaying either a bulk like dissociation behavior or forming ionic complexes inside the hydrogel film.

  15. Modeling deflagration waves out of hot spots

    Science.gov (United States)

    Partom, Yehuda

    2017-01-01

    It is widely accepted that shock initiation and detonation of heterogeneous explosives comes about by a two-step process known as ignition and growth. In the first step a shock sweeping through an explosive cell (control volume) creates hot spots that become ignition sites. In the second step, deflagration waves (or burn waves) propagate out of those hot spots and transform the reactant in the cell into reaction products. The macroscopic (or average) reaction rate of the reactant in the cell depends on the speed of those deflagration waves and on the average distance between neighboring hot spots. Here we simulate the propagation of deflagration waves out of hot spots on the mesoscale in axial symmetry using a 2D hydrocode, to which we add heat conduction and bulk reaction. The propagation speed of the deflagration waves may depend on both pressure and temperature. It depends on pressure for quasistatic loading near ambient temperature, and on temperature at high temperatures resulting from shock loading. From the simulation we obtain deflagration fronts emanating out of the hot spots. For 8 to 13 GPa shocks, the emanating fronts propagate as deflagration waves to consume the explosive between hot spots. For higher shock levels deflagration waves may interact with the sweeping shock to become detonation waves on the mesoscale. From the simulation results we extract average deflagration wave speeds.

  16. Unblinding the dark matter blind spots

    Science.gov (United States)

    Han, Tao; Kling, Felix; Su, Shufang; Wu, Yongcheng

    2017-02-01

    The dark matter (DM) blind spots in the Minimal Supersymmetric Standard Model (MSSM) refer to the parameter regions where the couplings of the DM particles to the Z-boson or the Higgs boson are almost zero, leading to vanishingly small signals for the DM direct detections. In this paper, we carry out comprehensive analyses for the DM searches under the blind-spot scenarios in MSSM. Guided by the requirement of acceptable DM relic abundance, we explore the complementary coverage for the theory parameters at the LHC, the projection for the future underground DM direct searches, and the indirect searches from the relic DM annihilation into photons and neutrinos. We find that (i) the spin-independent (SI) blind spots may be rescued by the spin-dependent (SD) direct detection in the future underground experiments, and possibly by the indirect DM detections from IceCube and SuperK neutrino experiments; (ii) the detection of gamma rays from Fermi-LAT may not reach the desirable sensitivity for searching for the DM blind-spot regions; (iii) the SUSY searches at the LHC will substantially extend the discovery region for the blind-spot parameters. The dark matter blind spots thus may be unblinded with the collective efforts in future DM searches.

  17. ALPHA-LACTALBUMIN GENOTYPES IDENTIFICATION IN ROMANIAN BLACK SPOTTED CATTLE BREED

    Directory of Open Access Journals (Sweden)

    R.A. VĂTĂSESCU

    2013-12-01

    Full Text Available Alpha-lactalbumin (α-La is a major milk protein essential for the biosynthesis of lactose at the level of mammary glands. α-La directly influences the quality and the volume of the milk since it is directly involved in the lactose synthesis (Ashwell et al., 1997. The PCR-RFLP test was performed to distinguish the different alleles in a population of Romanian Black Spotted cattle, a dairy breed. Genetic polymorphism was detected by digestion with the endonuclease MnlI, followed by electrophoresis in high resolution agarose gel stained with ethidium bromide. Sixty DNA samples from Romanian Black Spotted breed were analyzed for A and B variants. The PCRRFLP test makes feasible the inclusion of α-La genotypes in breeding plans and cattle selection.

  18. Replication of micro and nano surface geometries

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard; Hocken, R.J.; Tosello, Guido

    2011-01-01

    : manufacture of net-shape micro/nano surfaces, tooling (i.e. master making), and surface quality control (metrology, inspection). Replication processes and methods as well as the metrology of surfaces to determine the degree of replication are presented and classified. Examples from various application areas...... are given including replication for surface texture measurements, surface roughness standards, manufacture of micro and nano structured functional surfaces, replicated surfaces for optical applications (e.g. optical gratings), and process chains based on combinations of repeated surface replication steps....

  19. Replication of prions in differentiated muscle cells.

    Science.gov (United States)

    Herbst, Allen; Aiken, Judd M; McKenzie, Debbie

    2014-01-01

    We have demonstrated that prions accumulate to high levels in non-proliferative C2C12 myotubes. C2C12 cells replicate as myoblasts but can be differentiated into myotubes. Earlier studies indicated that C2C12 myoblasts are not competent for prion replication. (1) We confirmed that observation and demonstrated, for the first time, that while replicative myoblasts do not accumulate PrP(Sc), differentiated post-mitotic myotube cultures replicate prions robustly. Here we extend our observations and describe the implication and utility of this system for replicating prions.

  20. Myc localizes to histone locus bodies during replication in Drosophila.

    Directory of Open Access Journals (Sweden)

    Kaveh Daneshvar

    Full Text Available Myc is an important protein at the center of multiple pathways required for growth and proliferation in animals. The absence of Myc is lethal in flies and mice, and its over-production is a potent inducer of over-proliferation and cancer. Myc protein is localized to the nucleus where it executes its many functions, however the specific sub-nuclear localization of Myc has rarely been reported. The work we describe here began with an observation of unexpected, punctate spots of Myc protein in certain regions of Drosophila embryos. We investigated the identity of these puncta and demonstrate that Myc is co-localized with coilin, a marker for sub-nuclear organelles known as Cajal Bodies (CBs, in embryos, larvae and ovaries. Using antibodies specific for U7 snRNP component Lsm11, we show that the majority of Myc and coilin co-localization occurs in Histone Locus Bodies (HLBs, the sites of histone mRNA transcription and processing. Furthermore, Myc localizes to HLBs only during replication in mitotic and endocycling cells, suggesting that its role there relates to replication-dependent canonical histone gene transcription. These results provide evidence that sub-nuclear localization of Myc is cell-cycle dependent and potentially important for histone mRNA production and processing.

  1. DNA replication stress: causes, resolution and disease.

    Science.gov (United States)

    Mazouzi, Abdelghani; Velimezi, Georgia; Loizou, Joanna I

    2014-11-15

    DNA replication is a fundamental process of the cell that ensures accurate duplication of the genetic information and subsequent transfer to daughter cells. Various pertubations, originating from endogenous or exogenous sources, can interfere with proper progression and completion of the replication process, thus threatening genome integrity. Coordinated regulation of replication and the DNA damage response is therefore fundamental to counteract these challenges and ensure accurate synthesis of the genetic material under conditions of replication stress. In this review, we summarize the main sources of replication stress and the DNA damage signaling pathways that are activated in order to preserve genome integrity during DNA replication. We also discuss the association of replication stress and DNA damage in human disease and future perspectives in the field. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Replication Stress: A Lifetime of Epigenetic Change

    Directory of Open Access Journals (Sweden)

    Simran Khurana

    2015-09-01

    Full Text Available DNA replication is essential for cell division. Challenges to the progression of DNA polymerase can result in replication stress, promoting the stalling and ultimately collapse of replication forks. The latter involves the formation of DNA double-strand breaks (DSBs and has been linked to both genome instability and irreversible cell cycle arrest (senescence. Recent technological advances have elucidated many of the factors that contribute to the sensing and repair of stalled or broken replication forks. In addition to bona fide repair factors, these efforts highlight a range of chromatin-associated changes at and near sites of replication stress, suggesting defects in epigenome maintenance as a potential outcome of aberrant DNA replication. Here, we will summarize recent insight into replication stress-induced chromatin-reorganization and will speculate on possible adverse effects for gene expression, nuclear integrity and, ultimately, cell function.

  3. Correlation of acidic and basic carrier ampholyte and immobilized pH gradient two-dimensional gel electrophoresis patterns based on mass spectrometric protein identification

    DEFF Research Database (Denmark)

    Nawrocki, A; Larsen, Martin Røssel; Podtelejnikov, A V

    1998-01-01

    Separation of proteins on either carrier ampholyte-based or immobilized pH gradient-based two-dimensional (2-D) gels gives rise to electrophoretic patterns that are difficult to compare visually. In this paper we have used matrix-assisted laser desorption/ionization mass spectrometry (MALDI......-references demonstrated that there is no obvious pattern by which the mobility of a protein in one gel system can be used to predict its mobility in the other. Thus, as laboratories adopt the immobilized pH gradient-based 2-D gel systems, the only reliable means of translating the data gained with the carrier ampholyte......-MS) to determine the identities of 335 protein spots in these two 2-D gel systems, including a substantial number of basic proteins which had never been identified before. Proteins that were identified in both gel systems allowed us to cross-reference the gel patterns. Vector analysis of these cross...

  4. 7 CFR 28.423 - Middling Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Middling Spotted Color. 28.423 Section 28.423... REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Spotted Cotton § 28.423 Middling Spotted Color. Middling Spotted Color is color which is within the range represented by a set of samples in the custody...

  5. The glyceraldehyde-3-phosphate dehydrogenase and the small GTPase Rab 2 are crucial for Brucella replication.

    Directory of Open Access Journals (Sweden)

    Emilie Fugier

    2009-06-01

    Full Text Available The intracellular pathogen Brucella abortus survives and replicates inside host cells within an endoplasmic reticulum (ER-derived replicative organelle named the "Brucella-containing vacuole" (BCV. Here, we developed a subcellular fractionation method to isolate BCVs and characterize for the first time the protein composition of its replicative niche. After identification of BCV membrane proteins by 2 dimensional (2D gel electrophoresis and mass spectrometry, we focused on two eukaryotic proteins: the glyceraldehyde-3-phosphate dehydrogenase (GAPDH and the small GTPase Rab 2 recruited to the vacuolar membrane of Brucella. These proteins were previously described to localize on vesicular and tubular clusters (VTC and to regulate the VTC membrane traffic between the endoplasmic reticulum (ER and the Golgi. Inhibition of either GAPDH or Rab 2 expression by small interfering RNA strongly inhibited B. abortus replication. Consistent with this result, inhibition of other partners of GAPDH and Rab 2, such as COPI and PKC iota, reduced B. abortus replication. Furthermore, blockage of Rab 2 GTPase in a GDP-locked form also inhibited B. abortus replication. Bacteria did not fuse with the ER and instead remained in lysosomal-associated membrane vacuoles. These results reveal an essential role for GAPDH and the small GTPase Rab 2 in B. abortus virulence within host cells.

  6. Thixotropic gel for vadose zone remediation

    Science.gov (United States)

    Riha, Brian D.

    2012-07-03

    A thixotropic gel suitable for use in subsurface bioremediation is provided along with a process of using the gel. The thixotropic gel provides a non-migrating injectable substrate that can provide below ground barrier properties. In addition, the gel components provide for a favorable environment in which certain contaminants are preferentially sequestered in the gel and subsequently remediated by either indigenous or introduced microorganisms.

  7. Thixotropic gel for vadose zone remediation

    Science.gov (United States)

    Rhia, Brian D.

    2011-03-01

    A thixotropic gel suitable for use in subsurface bioremediation is provided along with a process of using the gel. The thixotropic gel provides a non-migrating injectable substrate that can provide below ground barrier properties. In addition, the gel components provide for a favorable environment in which certain contaminants are preferentially sequestered in the gel and subsequently remediated by either indigenous or introduced microorganisms.

  8. Thixotropic gel for vadose zone remediation

    Energy Technology Data Exchange (ETDEWEB)

    Riha, Brian D.; Looney, Brian B.

    2015-10-27

    A thixotropic gel suitable for use in subsurface bioremediation is provided along with a process of using the gel. The thixotropic gel provides a non-migrating injectable substrate that can provide below ground barrier properties. In addition, the gel components provide for a favorable environment in which certain contaminants are preferentially sequestered in the gel and subsequently remediated by either indigenous or introduced microorganisms.

  9. Severity of banana leaf spot in an intercropping system in two cycles of banana Prata Anã

    Directory of Open Access Journals (Sweden)

    Valdeir Dias Gonçalves

    2008-01-01

    Full Text Available Prata Anã is the most planted banana cultivar in northern Minas Gerais, Brazil. It is however susceptible toseveral pathogens. This study was carried out to evaluate the disease severity of banana leaf spot in the Prata Anã cv. in thefirst and second cycle under six different planting systems. The randomized block experimental design was used with sixtreatments and four replications. In an evaluation of the severity of banana leaf spot, no disease symptoms were found onThap Maeo and Caipira. The evolution curve of the disease indicated seasonal effects in the first and second cycles. Theseverity of banana leaf spot was highest soon after the regional rainy period from November to March. A comparison of themeans of the evaluations indicated a reduction in disease severity from the first to the second cycle.

  10. Self-replication of DNA rings

    Science.gov (United States)

    Kim, Junghoon; Lee, Junwye; Hamada, Shogo; Murata, Satoshi; Ha Park, Sung

    2015-06-01

    Biology provides numerous examples of self-replicating machines, but artificially engineering such complex systems remains a formidable challenge. In particular, although simple artificial self-replicating systems including wooden blocks, magnetic systems, modular robots and synthetic molecular systems have been devised, such kinematic self-replicators are rare compared with examples of theoretical cellular self-replication. One of the principal reasons for this is the amount of complexity that arises when you try to incorporate self-replication into a physical medium. In this regard, DNA is a prime candidate material for constructing self-replicating systems due to its ability to self-assemble through molecular recognition. Here, we show that DNA T-motifs, which self-assemble into ring structures, can be designed to self-replicate through toehold-mediated strand displacement reactions. The inherent design of these rings allows the population dynamics of the systems to be controlled. We also analyse the replication scheme within a universal framework of self-replication and derive a quantitative metric of the self-replicability of the rings.

  11. DNA Replication via Entanglement Swapping

    CERN Document Server

    Pusuluk, Onur

    2010-01-01

    Quantum effects are mainly used for the determination of molecular shapes in molecular biology, but quantum information theory may be a more useful tool to understand the physics of life. Molecular biology assumes that function is explained by structure, the complementary geometries of molecules and weak intermolecular hydrogen bonds. However, both this assumption and its converse are possible if organic molecules and quantum circuits/protocols are considered as hardware and software of living systems that are co-optimized during evolution. In this paper, we try to model DNA replication as a multiparticle entanglement swapping with a reliable qubit representation of nucleotides. In the model, molecular recognition of a nucleotide triggers an intrabase entanglement corresponding to a superposition state of different tautomer forms. Then, base pairing occurs by swapping intrabase entanglements with interbase entanglements.

  12. A simple laser ablation ICPMS method for the determination of trace metals in a resin gel.

    Science.gov (United States)

    Gao, Yue; Lehto, Niklas

    2012-04-15

    Trace metal analysis of DGT gels using laser ablation inductively coupled plasma (LA-ICP-MS) has traditionally been carried out by ablating single spots along a line to provide high resolution data on trace metal distributions on a resin gel. This work compares the performance of two different LA-ICPMS systems, one at Lancaster University, UK and another at VUB, Belgium, in terms of instrument sensitivity and limit of detection in the analysis of trace metals (Co, Ni, Cu, Zn, Cd, and Pb) bound by a DGT resin gel using SPR-IDA resin. No defocusing of the laser beam was necessary to prevent burning through the resin gel and the internal standardization became very simple by using (13)C, naturally present in the resin-gel, instead of impregnating a back-up layer with (115)In. Furthermore, this work also explores the option of analysing the spatial distribution of resin bound trace metals by means of ablating a continuous line between two points and considers the advantages of using this approach. The work found that the LODs assessed on blank samples for Cu and Pb are similar for both LA-ICPMS systems, while for Co, Ni and Zn they are lower for the one at VUB and for Cd for the other one at Lancaster. The work found that the laser ablation systems at the two laboratories allowed more precise control over laser power and spot size than previously reported. For the line scan, the optimum scan parameters were determined as: scan speed of 50 μm s(-1), output energy of 40% and repetition rate of 30 Hz. An acquisition time of 25 ms, resulted in a much lower resolution (10 μm) compared to the spot ablation (a crater size of 100 μm and also some space between craters) and a better sensitivity. The LODs using the line scan were found to be lower than those obtained by the spot ablation. However, for some of the metals the difference is rather small. This work suggests that the time and gas consumption achieved by using the line scan is about 30% lower than for the

  13. Therapeutic targeting of replicative immortality.

    Science.gov (United States)

    Yaswen, Paul; MacKenzie, Karen L; Keith, W Nicol; Hentosh, Patricia; Rodier, Francis; Zhu, Jiyue; Firestone, Gary L; Matheu, Ander; Carnero, Amancio; Bilsland, Alan; Sundin, Tabetha; Honoki, Kanya; Fujii, Hiromasa; Georgakilas, Alexandros G; Amedei, Amedeo; Amin, Amr; Helferich, Bill; Boosani, Chandra S; Guha, Gunjan; Ciriolo, Maria Rosa; Chen, Sophie; Mohammed, Sulma I; Azmi, Asfar S; Bhakta, Dipita; Halicka, Dorota; Niccolai, Elena; Aquilano, Katia; Ashraf, S Salman; Nowsheen, Somaira; Yang, Xujuan

    2015-12-01

    One of the hallmarks of malignant cell populations is the ability to undergo continuous proliferation. This property allows clonal lineages to acquire sequential aberrations that can fuel increasingly autonomous growth, invasiveness, and therapeutic resistance. Innate cellular mechanisms have evolved to regulate replicative potential as a hedge against malignant progression. When activated in the absence of normal terminal differentiation cues, these mechanisms can result in a state of persistent cytostasis. This state, termed "senescence," can be triggered by intrinsic cellular processes such as telomere dysfunction and oncogene expression, and by exogenous factors such as DNA damaging agents or oxidative environments. Despite differences in upstream signaling, senescence often involves convergent interdependent activation of tumor suppressors p53 and p16/pRB, but can be induced, albeit with reduced sensitivity, when these suppressors are compromised. Doses of conventional genotoxic drugs required to achieve cancer cell senescence are often much lower than doses required to achieve outright cell death. Additional therapies, such as those targeting cyclin dependent kinases or components of the PI3K signaling pathway, may induce senescence specifically in cancer cells by circumventing defects in tumor suppressor pathways or exploiting cancer cells' heightened requirements for telomerase. Such treatments sufficient to induce cancer cell senescence could provide increased patient survival with fewer and less severe side effects than conventional cytotoxic regimens. This positive aspect is countered by important caveats regarding senescence reversibility, genomic instability, and paracrine effects that may increase heterogeneity and adaptive resistance of surviving cancer cells. Nevertheless, agents that effectively disrupt replicative immortality will likely be valuable components of new combinatorial approaches to cancer therapy. Copyright © 2015 The Authors

  14. Superoscillating electron wave functions with subdiffraction spots

    Science.gov (United States)

    Remez, Roei; Tsur, Yuval; Lu, Peng-Han; Tavabi, Amir H.; Dunin-Borkowski, Rafal E.; Arie, Ady

    2017-03-01

    Almost one and a half centuries ago, Abbe [Arch. Mikrosk. Anat. 9, 413 (1873), 10.1007/BF02956173] and shortly after Lord Rayleigh [Philos. Mag. Ser. 5 8, 261 (1879), 10.1080/14786447908639684] showed that, when an optical lens is illuminated by a plane wave, a diffraction-limited spot with radius 0.61 λ /sinα is obtained, where λ is the wavelength and α is the semiangle of the beam's convergence cone. However, spots with much smaller features can be obtained at the focal plane when the lens is illuminated by an appropriately structured beam. Whereas this concept is known for light beams, here, we show how to realize it for a massive-particle wave function, namely, a free electron. We experimentally demonstrate an electron central spot of radius 106 pm, which is more than two times smaller than the diffraction limit of the experimental setup used. In addition, we demonstrate that this central spot can be structured by adding orbital angular momentum to it. The resulting superoscillating vortex beam has a smaller dark core with respect to a regular vortex beam. This family of electron beams having hot spots with arbitrarily small features and tailored structures could be useful for studying electron-matter interactions with subatomic resolution.

  15. Sol-gel derived sorbents

    Science.gov (United States)

    Sigman, Michael E.; Dindal, Amy B.

    2003-11-11

    Described is a method for producing copolymerized sol-gel derived sorbent particles for the production of copolymerized sol-gel derived sorbent material. The method for producing copolymerized sol-gel derived sorbent particles comprises adding a basic solution to an aqueous metal alkoxide mixture for a pH.ltoreq.8 to hydrolyze the metal alkoxides. Then, allowing the mixture to react at room temperature for a precalculated period of time for the mixture to undergo an increased in viscosity to obtain a desired pore size and surface area. The copolymerized mixture is then added to an immiscible, nonpolar solvent that has been heated to a sufficient temperature wherein the copolymerized mixture forms a solid upon the addition. The solid is recovered from the mixture, and is ready for use in an active sampling trap or activated for use in a passive sampling trap.

  16. Copolymers For Capillary Gel Electrophoresis

    Science.gov (United States)

    Liu, Changsheng; Li, Qingbo

    2005-08-09

    This invention relates to an electrophoresis separation medium having a gel matrix of at least one random, linear copolymer comprising a primary comonomer and at least one secondary comonomer, wherein the comonomers are randomly distributed along the copolymer chain. The primary comonomer is an acrylamide or an acrylamide derivative that provides the primary physical, chemical, and sieving properties of the gel matrix. The at least one secondary comonomer imparts an inherent physical, chemical, or sieving property to the copolymer chain. The primary and secondary comonomers are present in a ratio sufficient to induce desired properties that optimize electrophoresis performance. The invention also relates to a method of separating a mixture of biological molecules using this gel matrix, a method of preparing the novel electrophoresis separation medium, and a capillary tube filled with the electrophoresis separation medium.

  17. The One-Kilobase DNA Fragment Upstream of the ardC Actin Gene of Physarum polycephalum Is Both a Replicator and a Promoter

    Science.gov (United States)

    Pierron, Gérard; Pallotta, Dominick; Bénard, Marianne

    1999-01-01

    The 1-kb DNA fragment upstream of the ardC actin gene of Physarum polycephalum promotes the transcription of a reporter gene either in a transient-plasmid assay or as an integrated copy in an ectopic position, defining this region as the transcriptional promoter of the ardC gene (PardC). Since we mapped an origin of replication activated at the onset of S phase within this same fragment, we examined the pattern of replication of a cassette containing the PardC promoter and the hygromycin phosphotransferase gene, hph, integrated into two different chromosomal sites. In both cases, we show by two-dimensional agarose gel electrophoresis that an efficient, early activated origin coincides with the ectopic PardC fragment. One of the integration sites was a normally late-replicating region. The presence of the ectopic origin converted this late-replicating domain into an early-replicating domain in which replication forks propagate with kinetics indistinguishable from those of the native PardC replicon. This is the first demonstration that initiation sites for DNA replication in Physarum correspond to cis-acting replicator sequences. This work also confirms the close proximity of a replication origin and a promoter, with both functions being located within the 1-kb proximal region of the ardC actin gene. A more precise location of the replication origin with respect to the transcriptional promoter must await the development of a functional autonomously replicating sequence assay in Physarum. PMID:10207074

  18. Two host microRNAs influence WSSV replication via STAT gene regulation

    Science.gov (United States)

    Huang, Ying; Wang, Wen; Ren, Qian

    2016-01-01

    MicroRNAs (miRNAs) have important roles in post-transcriptional regulation of gene expression. During viral infection, viruses utilize hosts to enhance their replication by altering cellular miRNAs. The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway plays crucial roles in the antiviral responses. In this study, two miRNAs (miR-9041 and miR-9850) from Macrobrachium rosenbergii were found to promote white spot syndrome virus (WSSV) replication. The up-regulation of miR-9041 or miR-9850 suppresses STAT expression in the gills of M. rosenbergii, which subsequently down-regulates the expression of its downstream dynamin (Dnm) genes: Dnm1, Dnm2, and Dnm3. Knockdown of miR-9041 and miR-9850 restricts WSSV replication by up-regulating STAT and Dnm gene expression. The silencing of STAT, Dnm1, Dnm2, or Dnm3 led to an increase of the number of WSSV copies in shrimp. The injection of recombinant Dnm1, Dnm2, or Dnm3 proteins could inhibit WSSV replication in vivo. Overall, our research indicates the roles of host miRNAs in the enhancement of WSSV replication by regulating the host JAK/STAT pathway. PMID:27029712

  19. Regulation of Unperturbed DNA Replication by Ubiquitylation

    Directory of Open Access Journals (Sweden)

    Sara Priego Moreno

    2015-06-01

    Full Text Available Posttranslational modification of proteins by means of attachment of a small globular protein ubiquitin (i.e., ubiquitylation represents one of the most abundant and versatile mechanisms of protein regulation employed by eukaryotic cells. Ubiquitylation influences almost every cellular process and its key role in coordination of the DNA damage response is well established. In this review we focus, however, on the ways ubiquitylation controls the process of unperturbed DNA replication. We summarise the accumulated knowledge showing the leading role of ubiquitin driven protein degradation in setting up conditions favourable for replication origin licensing and S-phase entry. Importantly, we also present the emerging major role of ubiquitylation in coordination of the active DNA replication process: preventing re-replication, regulating the progression of DNA replication forks, chromatin re-establishment and disassembly of the replisome at the termination of replication forks.

  20. Chromosome replication and segregation in bacteria.

    Science.gov (United States)

    Reyes-Lamothe, Rodrigo; Nicolas, Emilien; Sherratt, David J

    2012-01-01

    In dividing cells, chromosome duplication once per generation must be coordinated with faithful segregation of newly replicated chromosomes and with cell growth and division. Many of the mechanistic details of bacterial replication elongation are well established. However, an understanding of the complexities of how replication initiation is controlled and coordinated with other cellular processes is emerging only slowly. In contrast to eukaryotes, in which replication and segregation are separate in time, the segregation of most newly replicated bacterial genetic loci occurs sequentially soon after replication. We compare the strategies used by chromosomes and plasmids to ensure their accurate duplication and segregation and discuss how these processes are coordinated spatially and temporally with growth and cell division. We also describe what is known about the three conserved families of ATP-binding proteins that contribute to chromosome segregation and discuss their inter-relationships in a range of disparate bacteria.

  1. Simulating acoustic waves in spotted stars

    CERN Document Server

    Papini, Emanuele; Gizon, Laurent; Hanasoge, Shravan M

    2015-01-01

    Acoustic modes of oscillation are affected by stellar activity, however it is unclear how starspots contribute to these changes. Here we investigate the non-magnetic effects of starspots on global modes with angular degree $\\ell \\leq 2$ in highly active stars, and characterize the spot seismic signature on synthetic light curves. We perform 3D time-domain simulations of linear acoustic waves to study their interaction with a model starspot. We model the spot as a 3D change in the sound speed stratification with respect to a convectively stable stellar background, built from solar Model S. We perform a parametric study by considering different depths and perturbation amplitudes. Exact numerical simulations allow investigation of the wavefield-spot interaction beyond first order perturbation theory. The interaction of the axisymmetric modes with the starspot is strongly nonlinear. As mode frequency increases, the frequency shifts for radial modes exceed the value predicted by linear theory, while the shifts for...

  2. Note: Resistance spot welding using a microgripper

    Science.gov (United States)

    Hwang, G.; Podrzaj, P.; Hashimoto, H.

    2013-10-01

    Interest in thin-film nanostructures as building blocks for nanoelectronics and nanoelectromechanical systems (NEMS) is increasing. Resistance spot welding (RSW) on a nano or micro scale can play a significant role; similar to that of its macro counterpart for forming connections in device assembly processes. This Note presents a novel micron scale RSW technique using a microgripper as mobile spot welding electrodes to assemble ultra-thin film nanostructures. As an example, assembly of three-dimensional helical nanobelt (HNB) based device was successfully demonstrated using the proposed system. The spot-welding process was fully monitored by the built-in capacitive micro force sensor of the microgripper. Experiments show that RSW, using the microgripper, provides a stable electrical contact with sufficient mechanical strength for the construction of devices such as HNB based devices demonstrated here.

  3. PREDICTING RELEVANT EMPTY SPOTS IN SOCIAL INTERACTION

    Institute of Scientific and Technical Information of China (English)

    Yoshiharu MAENO; Yukio OHSAWA

    2008-01-01

    An empty spot refers to an empty hard-to-fill space which can be found in the records of the social interaction, and is the clue to the persons in the underlying social network who do not appear in the records. This contribution addresses a problem to predict relevant empty spots in social interaction. Homogeneous and inhomogeneous networks are studied as a model underlying the social interaction. A heuristic predictor function method is presented as a new method to address the problem. Simulation experiment is demonstrated over a homogeneous network. A test data set in the form of market baskets is generated from the simulated communication. Precision to predict the empty spots is calculated to demonstrate the performance of the presented method.

  4. Semiconservative replication in the quasispecies model

    Science.gov (United States)

    Tannenbaum, Emmanuel; Deeds, Eric J.; Shakhnovich, Eugene I.

    2004-06-01

    This paper extends Eigen’s quasispecies equations to account for the semiconservative nature of DNA replication. We solve the equations in the limit of infinite sequence length for the simplest case of a static, sharply peaked fitness landscape. We show that the error catastrophe occurs when μ , the product of sequence length and per base pair mismatch probability, exceeds 2 ln [2/ ( 1+1/k ) ] , where k>1 is the first-order growth rate constant of the viable “master” sequence (with all other sequences having a first-order growth rate constant of 1 ). This is in contrast to the result of ln k for conservative replication. In particular, as k→∞ , the error catastrophe is never reached for conservative replication, while for semiconservative replication the critical μ approaches 2 ln 2 . Semiconservative replication is therefore considerably less robust than conservative replication to the effect of replication errors. We also show that the mean equilibrium fitness of a semiconservatively replicating system is given by k ( 2 e-μ/2 -1 ) below the error catastrophe, in contrast to the standard result of k e-μ for conservative replication (derived by Kimura and Maruyama in 1966). From this result it is readily shown that semiconservative replication is necessary to account for the observation that, at sufficiently high mutagen concentrations, faster replicating cells will die more quickly than more slowly replicating cells. Thus, in contrast to Eigen’s original model, the semiconservative quasispecies equations are able to provide a mathematical basis for explaining the efficacy of mutagens as chemotherapeutic agents.

  5. Regulation of chromosomal replication in Caulobacter crescentus.

    Science.gov (United States)

    Collier, Justine

    2012-03-01

    The alpha-proteobacterium Caulobacter crescentus is characterized by its asymmetric cell division, which gives rise to a replicating stalked cell and a non-replicating swarmer cell. Thus, the initiation of chromosomal replication is tightly regulated, temporally and spatially, to ensure that it is coordinated with cell differentiation and cell cycle progression. Waves of DnaA and CtrA activities control when and where the initiation of DNA replication will take place in C. crescentus cells. The conserved DnaA protein initiates chromosomal replication by directly binding to sites within the chromosomal origin (Cori), ensuring that DNA replication starts once and only once per cell cycle. The CtrA response regulator represses the initiation of DNA replication in swarmer cells and in the swarmer compartment of pre-divisional cells, probably by competing with DnaA for binding to Cori. CtrA and DnaA are controlled by multiple redundant regulatory pathways that include DNA methylation-dependent transcriptional regulation, temporally regulated proteolysis and the targeting of regulators to specific locations within the cell. Besides being critical regulators of chromosomal replication, CtrA and DnaA are also master transcriptional regulators that control the expression of many genes, thus connecting DNA replication with other events of the C. crescentus cell cycle. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Comparison of three replication strategies in complex multicellular organisms: Asexual replication, sexual replication with identical gametes, and sexual replication with distinct sperm and egg gametes

    Science.gov (United States)

    Tannenbaum, Emmanuel

    2008-01-01

    This paper studies the mutation-selection balance in three simplified replication models. The first model considers a population of organisms replicating via the production of asexual spores. The second model considers a sexually replicating population that produces identical gametes. The third model considers a sexually replicating population that produces distinct sperm and egg gametes. All models assume diploid organisms whose genomes consist of two chromosomes, each of which is taken to be functional if equal to some master sequence, and defective otherwise. In the asexual population, the asexual diploid spores develop directly into adult organisms. In the sexual populations, the haploid gametes enter a haploid pool, where they may fuse with other haploids. The resulting immature diploid organisms then proceed to develop into mature organisms. Based on an analysis of all three models, we find that, as organism size increases, a sexually replicating population can only outcompete an asexually replicating population if the adult organisms produce distinct sperm and egg gametes. A sexual replication strategy that is based on the production of large numbers of sperm cells to fertilize a small number of eggs is found to be necessary in order to maintain a sufficiently low cost for sex for the strategy to be selected for over a purely asexual strategy. We discuss the usefulness of this model in understanding the evolution and maintenance of sexual replication as the preferred replication strategy in complex, multicellular organisms.

  7. Prevention and treatment of white spot lesions in orthodontic patients

    Directory of Open Access Journals (Sweden)

    Maryam Khoroushi

    2017-01-01

    Full Text Available Decalcification of enamel, appearing as white spot lesions (WSLs, around fixed orthodontic appliances is a major challenge during and after fixed orthodontic treatment by considering the fact that the goal of orthodontic treatment is to enhance facial and dental esthetic appearance. Banded or bonded teeth exhibit a significantly higher rate of WSLs compared to the controls with no braces as fixed appliances and the bonding materials promote retention of biofilms. These lesions are managed in the first step by establishing good oral hygiene habits and prophylaxis with topical fluorides, including high-fluoride toothpastes, fluoride mouthwashes, gels, varnishes, fluoride-containing bonding materials, and elastic ligatures. Recently, other materials and methods have been recommended, including the application of casein phosphopeptides-amorphous calcium phosphate, antiseptics, probiotics, polyols, sealants, laser, tooth bleaching agents, resin infiltration, and microabrasion. This article reviews the currently used methods to manage enamel demineralization during and after orthodontic treatment and the risk factors and preventive measures based on the latest evidence.

  8. Isozyme Analysis of Spotted Halibut Verasper variegatus Temminck et Schlegel

    Institute of Scientific and Technical Information of China (English)

    LIU Manhong; GAO Tianxiang; ZHANG Xiumei; CHEN Siqing

    2005-01-01

    To investigate the tissue-specificities of isozymes and the genetic structure of wild spotted halibut ( Verasper vari gatus) population, horizontal starch gel electrophoresis was performed on 45 individuals collected in part of the Yellow Sea.The performances of 17 isozymes in 8 kinds of tissues or organs were screened preliminarily in a TC-7.0 buffer system. The results showed that the screened isozymes displayed remarkable tissue-specificities. Finally, 14 enzymes (AAT, ADH, EST,GPI, G3PDH, IDHP, LAP, LDH, MDH, MPI, PGDH, PGM, SDH and SOD) and 4 kinds of tissues (eye, skeleton mus cle, liver and heart) were selected for genetic analysis. Fourteen isozymes are encoded by 20 loci, and 9 of them are poly morphic. The polymorph ic loci are AAT-1*, GPI-2*, G3PDH*, IDHP-1*, LDH*, MPI*, PGM-1*, PGM-2* and SDH* , and the proportion of polymorphic loci is 0.4500 (P0.99). The mean values of observed and expected heterozygosities are 0.027 8 and 0.026 5, respectively and the average effective number of alleles is 1.067 5.

  9. Whole Genome Amplification from Blood Spot Samples.

    Science.gov (United States)

    Sørensen, Karina Meden

    2015-01-01

    Whole genome amplification is an invaluable technique when working with DNA extracted from blood spots, as the DNA obtained from this source often is too limited for extensive genetic analysis. Two techniques that amplify the entire genome are common. Here, both are described with focus on the benefits and drawbacks of each system. However, in order to obtain the best possible WGA result the quality of input DNA extracted from the blood spot is essential, but also time consumption, flexibility in format and elution volume and price of the technology are factors influencing system choice. Here, three DNA extraction techniques are described and the above aspects are compared between the systems.

  10. Screening effect on nanostructure of charged gel

    DEFF Research Database (Denmark)

    Sugiyama, M; Annaka, M; Hino, M

    2004-01-01

    Charge screening effects on nanostructures of N-isopropylacrylamide-sodium acrylate (NIPA-SA) and -acrylic acid (NIPA-AAc) gels are investigated with small-angle neutron scattering. The NIPA-SA and NIPA-AAc gels with low water content exhibit microphase separations with different dimensions....... The dehydrated NIPA-SA gel also makes the microphase separation but the dehydrated NIPA-AAc gel does not. These results indicate that ionic circumstance around charged bases strongly affects the nanostructures both of the dehydrated gel and the gel with low water content. (C) 2004 Elsevier B. V. All rights...

  11. Variation in T-SPOT.TB spot interpretation between independent observers from different laboratories.

    Science.gov (United States)

    Franken, Willeke P J; Thijsen, Steven; Wolterbeek, Ron; Bouwman, John J M; el Bannoudi, Hanane; Kik, Sandra V; van Dissel, Jaap T; Arend, Sandra M

    2009-10-01

    T-SPOT.TB is a specific assay for the diagnosis of tuberculosis. The assay needs to be performed with freshly isolated cells, and interpretation requires training. T-SPOT.TB has been used in various clinical-epidemiological settings, but so far no studies have evaluated the effect of interobserver variation in test reading. Our aim was to evaluate variation between different observers in reading T-SPOT.TB results. The study was nested within an ongoing cohort study, in which part of the T-SPOT.TB had been performed with frozen material. Culture plates were read visually by four different observers from two laboratories and by two automated readers. Of 313 T-SPOT.TB assays, 235 were performed with fresh cells and 78 were performed with frozen cells. No significant difference was found between results obtained with fresh cells and those obtained with frozen cells. The percentage of positive results varied between readers by maximally 15%; five/six raters were within a 6% difference in positive results. Analysis of the observed interrater differences showed that some individuals systematically counted more spots than others did. Because test interpretation includes subtraction of background values, this systematic variance had little influence on interindividual differences. The test result as positive or negative varied between independent raters, mainly due to samples with values around the cutoff. This warrants further study regarding determinants affecting the reading of T-SPOT.TB.

  12. Physicochemical behaviour of chitin gels.

    Science.gov (United States)

    Vachoud, L; Zydowicz, N; Domard, A

    2000-06-30

    Syneresis of chitin gels formed in the course of N-acetylation of chitosan in hydroalcoholic media has been studied. A critical cross-linking density related to a critical acetylation degree for which the gel undergoes weak syneresis and swells in water was shown (degree of acetylation (DA) 88%). Above this value, the weight loss during syneresis increases with DA. Conversely, syneresis decreases on increasing the polymer concentration, but disappears at a macroscopic level for a polymer concentration close to the critical concentration of entanglement in the initial solution. An increase in temperature favours the formation of hydrophobic interactions and new inter- and intramolecular hydrogen bondings. Due to the weak polyelectrolyte character of chitin, the weight of the gel depends on the pH and ionic strength of the media. Swelling-deswelling experiments show that the swelling of the gel is not fully reversible in relation with the formation of new cross-links during the depletion of the network. Our results reveals that the balance between segment-segment and segment-solvent interactions as well as the molecular mobility play the major role.

  13. Fluoride Rinses, Gels and Foams

    DEFF Research Database (Denmark)

    Twetman, Svante; Keller, Mette K

    2016-01-01

    AIM: The aim of this conference paper was to systematically review the quality of evidence and summarize the findings of clinical trials published after 2002 using fluoride mouth rinses, fluoride gels or foams for the prevention of dental caries. METHODS: Relevant papers were selected after an el...... brushing with fluoride toothpaste....

  14. Nonlinear elasticity of alginate gels

    Science.gov (United States)

    Hashemnejad, Seyed Meysam; Kundu, Santanu

    Alginate is a naturally occurring anionic polysaccharide extracted from brown algae. Because of biocompatibility, low toxicity, and simple gelation process, alginate gels are used in biomedical and food applications. Here, we report the rheological behavior of ionically crosslinked alginate gels, which are obtained by in situ gelation of alginates with calcium salts, in between two parallel plates of a rheometer. Strain stiffening behavior was captured using large amplitude oscillatory shear (LAOS) experiments. In addition, negative normal stress was observed for these gels, which has not been reported earlier for any polysaccharide networks. The magnitude of negative normal stress increases with applied strain and can exceed that of the shear stress at large strain. Rheological results fitted with a constitutive model that considers both stretching and bending of chains indicate that nonlinearity is likely related to the stretching of the chains between the crosslink junctions. The results provide an improved understanding of the deformation mechanism of ionically crosslinked alginate gel and the results will be important in developing synthetic extracellular matrix (ECM) from these materials.

  15. Spot Weight Adaptation for Moving Target in Spot Scanning Proton Therapy

    Directory of Open Access Journals (Sweden)

    Paul eMorel

    2015-05-01

    Full Text Available Purpose: This study describes a real-time spot weight adaptation method in spot-scanning proton therapy for moving target or moving patient, so that the resultant dose distribution closely matches the planned dose distribution. Materials and Methods: The method proposed in this study adapts the weight (MU of the delivering pencil beam to that of the target spot it will actually hit during patient/target motion. The target spot a certain delivering pencil beam may hit relies on patient monitoring and/or motion modeling using four-dimensional (4D CT. After the adapted delivery, the required total weight (MU for this target spot is then subtracted from the planned value. With continuous patient motion and continuous spot scanning, the planned doses to all target spots will eventually be all fulfilled. In a proof-of-principle test, a lung case was presented with realistic temporal and motion parameters; the resultant dose distribution using spot weight adaptation was compared to that without using this method. The impact of the real-time patient/target position tracking or prediction was also investigated.Results: For moderate motion (i.e., mean amplitude 0.5 cm, D95% to the planning target volume (PTV was only 81.5% of the prescription (RX dose; with spot weight adaptation PTV D95% achieves 97.7%RX. For large motion amplitude (i.e., 1.5 cm, without spot weight adaptation PTV D95% is only 42.9% of RX; with spot weight adaptation, PTV D95% achieves 97.7%RX. Larger errors in patient/target position tracking or prediction led to worse final target coverage; an error of 3mm or smaller in patient/target position tracking is preferred. Conclusion: The proposed spot weight adaptation method was able to deliver the planned dose distribution and maintain target coverage when patient motion was involved. The successful implementation of this method would rely on accurate monitoring or prediction of patient/target motion.

  16. Dramatic Change in Jupiter's Great Red Spot

    Science.gov (United States)

    Simon, A. A.; Wong, M. H.; Rogers, J. H.; Orton, G. S.; de Pater, I.; Asay-Davis, X.; Carlson, R. W.; Marcus, P. S.

    2015-01-01

    Jupiter's Great Red Spot (GRS) is one of its most distinct and enduring features, having been continuously observed since the 1800's. It currently spans the smallest latitude and longitude size ever recorded. Here we show analyses of 2014 Hubble spectral imaging data to study the color, structure and internal dynamics of this long-live storm.

  17. Restricted spread of tomato spotted wilt virus

    NARCIS (Netherlands)

    Maris, P.C.; Joosten, N.N.; Goldbach, R.W.; Peters, D.

    2003-01-01

    Spread of Tomato spotted wilt virus (TSWV) and population development of its vector Frankliniella occidentalis were studied on the pepper accessions CPRO-1 and Pikante Reuzen, which are resistant and susceptible to thrips, respectively. Viruliferous thrips were released on plants of each accession (

  18. Pips and spots in the microwave sky

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Gonzalez, E.; Sanz, J.L.

    1989-04-15

    An analysis is presented of some local statistical properties in the microwave sky such as mean number of hotspots over the celestial sphere, mean size of a hotspot, mean number of pips at fixed declination and 95 per cent confidence interval for the threshold of the hottest spot or pip, associated with three different experiments. (author).

  19. The sweet spots in human communication.

    Science.gov (United States)

    Salem, Philip

    2011-07-01

    In baseball, the sweet spot is a special place on a bat where the batter can hit the ball with the most power. It is the place where the performances of the batter and pitcher collide with maximum effect. It is the place where the dynamic tension between opponents leads to transformation. The dynamic tension in all living systems is between similarity and difference. Chaos and complexity scholars recognized this tension as amounts of information. When the amounts of information were high, but not too high, the system moved to the edge of chaos, to the complexity regime, to strange attractors, or to chaos, depending on the model. The sweet spot is that range of relative variety, just the proper mix of similarity and difference, leading to transformation. This essay contains a model of human communication as an emergent social process with its own sweet spots. The essay also includes a description of current literature highlighting tensions between similarity and difference, and there is an exploration of the potential to move from one basin of attraction to another. The primary constraints on finding communication sweet spots are paradigmatic - adopting a process orientation, discovering the proper parameters, bracketing sequences to define initial conditions, and understanding the strengths and weaknesses of various modeling techniques.

  20. Studies on Typhus and Spotted Fever.

    Science.gov (United States)

    1981-02-01

    Heterogeneity among Rickettsia tsutsugamushi isolates: A protein analysis. 8. David J. Silverman, Charles L. Wisseman, Jr. and Anna Waddell. Envelopment and...the Conference and are also in press. 10. Paul Fiset, Charles L. Wisseman, Jr., A. Farhang-Azad, Harvey Fischman . Rocky Mountain Spotted Fever in

  1. Activity patterns of nesting Mexican Spotted Owls

    Science.gov (United States)

    David K. Delaney; Teryl G. Grubb; Paul Beier

    1999-01-01

    We collected 2,665 hr of behavioral information using video surveillance on 19 Mexican Spotted Owl (Strix occidentalis lucida) pairs between 25 April and 26 July 1996. Prey deliveries per day increased as the nesting season progressed, with an average of 2.68 prey deliveries during incubation, 4.10 items during brooding, and 4.51 items during the...

  2. Elliptical X-Ray Spot Measurement

    CERN Document Server

    Richardson, R A; Weir, J T; Richardson, Roger A.; Sampayan, Stephen; Weir, John T.

    2000-01-01

    The so-called roll bar measurement uses a heavy metal material, optically thick to x-rays, to form a shadow of the x-ray origination spot. This spot is where an energetic electron beam interacts with a high Z target. The material (the "roll bar") is slightly curved to avoid alignment problems. The roll bar is constructed and positioned so that the x-rays are shadowed in the horizontal and vertical directions, so information is obtained in two dimensions. If a beam profile is assumed (or measured by other means), the equivalent x-ray spot size can be calculated from the x-ray shadow cast by the roll bar. Thus the ellipticity of the beam can be calculated, assuming the ellipse of the x-ray spot is aligned with the roll bar. The data is recorded using a scintillator and gated camera. Data will be presented from measurements using the ETA II induction LINAC. The accuracy of the measurement is checked using small elliptical targets.

  3. Surface micro topography replication in injection moulding

    DEFF Research Database (Denmark)

    Arlø, Uffe Rolf

    of the mechanisms controlling topography replication. Surface micro topography replication in injection moulding depends on the main elements of  Process conditions  Plastic material  Mould topography In this work, the process conditions is the main factor considered, but the impact of plastic material...

  4. Replication and Robustness in Developmental Research

    Science.gov (United States)

    Duncan, Greg J.; Engel, Mimi; Claessens, Amy; Dowsett, Chantelle J.

    2014-01-01

    Replications and robustness checks are key elements of the scientific method and a staple in many disciplines. However, leading journals in developmental psychology rarely include explicit replications of prior research conducted by different investigators, and few require authors to establish in their articles or online appendices that their key…

  5. Completion of DNA replication in Escherichia coli.

    Science.gov (United States)

    Wendel, Brian M; Courcelle, Charmain T; Courcelle, Justin

    2014-11-18

    The mechanism by which cells recognize and complete replicated regions at their precise doubling point must be remarkably efficient, occurring thousands of times per cell division along the chromosomes of humans. However, this process remains poorly understood. Here we show that, in Escherichia coli, the completion of replication involves an enzymatic system that effectively counts pairs and limits cellular replication to its doubling point by allowing converging replication forks to transiently continue through the doubling point before the excess, over-replicated regions are incised, resected, and joined. Completion requires RecBCD and involves several proteins associated with repairing double-strand breaks including, ExoI, SbcDC, and RecG. However, unlike double-strand break repair, completion occurs independently of homologous recombination and RecA. In some bacterial viruses, the completion mechanism is specifically targeted for inactivation to allow over-replication to occur during lytic replication. The results suggest that a primary cause of genomic instabilities in many double-strand-break-repair mutants arises from an impaired ability to complete replication, independent from DNA damage.

  6. Replication and Robustness in Developmental Research

    Science.gov (United States)

    Duncan, Greg J.; Engel, Mimi; Claessens, Amy; Dowsett, Chantelle J.

    2014-01-01

    Replications and robustness checks are key elements of the scientific method and a staple in many disciplines. However, leading journals in developmental psychology rarely include explicit replications of prior research conducted by different investigators, and few require authors to establish in their articles or online appendices that their key…

  7. Using Replication Projects in Teaching Research Methods

    Science.gov (United States)

    Standing, Lionel G.; Grenier, Manuel; Lane, Erica A.; Roberts, Meigan S.; Sykes, Sarah J.

    2014-01-01

    It is suggested that replication projects may be valuable in teaching research methods, and also address the current need in psychology for more independent verification of published studies. Their use in an undergraduate methods course is described, involving student teams who performed direct replications of four well-known experiments, yielding…

  8. How frog embryos replicate their DNA reliably

    Science.gov (United States)

    Bechhoefer, John; Marshall, Brandon

    2007-03-01

    Frog embryos contain three billion base pairs of DNA. In early embryos (cycles 2-12), DNA replication is extremely rapid, about 20 min., and the entire cell cycle lasts only 25 min., meaning that mitosis (cell division) takes place in about 5 min. In this stripped-down cell cycle, there are no efficient checkpoints to prevent the cell from dividing before its DNA has finished replication - a disastrous scenario. Even worse, the many origins of replication are laid down stochastically and are also initiated stochastically throughout the replication process. Despite the very tight time constraints and despite the randomness introduced by origin stochasticity, replication is extremely reliable, with cell division failing no more than once in 10,000 tries. We discuss a recent model of DNA replication that is drawn from condensed-matter theories of 1d nucleation and growth. Using our model, we discuss different strategies of replication: should one initiate all origins as early as possible, or is it better to hold back and initiate some later on? Using concepts from extreme-value statistics, we derive the distribution of replication times given a particular scenario for the initiation of origins. We show that the experimentally observed initiation strategy for frog embryos meets the reliability constraint and is close to the one that requires the fewest resources of a cell.

  9. Mammalian RAD52 Functions in Break-Induced Replication Repair of Collapsed DNA Replication Forks

    DEFF Research Database (Denmark)

    Sotiriou, Sotirios K; Kamileri, Irene; Lugli, Natalia

    2016-01-01

    Human cancers are characterized by the presence of oncogene-induced DNA replication stress (DRS), making them dependent on repair pathways such as break-induced replication (BIR) for damaged DNA replication forks. To better understand BIR, we performed a targeted siRNA screen for genes whose depl...

  10. DNA replication catalyzed by herpes simplex virus type 1 proteins reveals trombone loops at the fork.

    Science.gov (United States)

    Bermek, Oya; Willcox, Smaranda; Griffith, Jack D

    2015-01-30

    Using purified replication factors encoded by herpes simplex virus type 1 and a 70-base minicircle template, we obtained robust DNA synthesis with leading strand products of >20,000 nucleotides and lagging strand fragments from 600 to 9,000 nucleotides as seen by alkaline gel electrophoresis. ICP8 was crucial for the synthesis on both strands. Visualization of the deproteinized products using electron microscopy revealed long, linear dsDNAs, and in 87%, one end, presumably the end with the 70-base circle, was single-stranded. The remaining 13% had multiple single-stranded segments separated by dsDNA segments 500 to 1,000 nucleotides in length located at one end. These features are diagnostic of the trombone mechanism of replication. Indeed, when the products were examined with the replication proteins bound, a dsDNA loop was frequently associated with the replication complex located at one end of the replicated DNA. Furthermore, the frequency of loops correlated with the fraction of DNA undergoing Okazaki fragment synthesis.

  11. Rescue from replication stress during mitosis.

    Science.gov (United States)

    Fragkos, Michalis; Naim, Valeria

    2017-04-03

    Genomic instability is a hallmark of cancer and a common feature of human disorders, characterized by growth defects, neurodegeneration, cancer predisposition, and aging. Recent evidence has shown that DNA replication stress is a major driver of genomic instability and tumorigenesis. Cells can undergo mitosis with under-replicated DNA or unresolved DNA structures, and specific pathways are dedicated to resolving these structures during mitosis, suggesting that mitotic rescue from replication stress (MRRS) is a key process influencing genome stability and cellular homeostasis. Deregulation of MRRS following oncogene activation or loss-of-function of caretaker genes may be the cause of chromosomal aberrations that promote cancer initiation and progression. In this review, we discuss the causes and consequences of replication stress, focusing on its persistence in mitosis as well as the mechanisms and factors involved in its resolution, and the potential impact of incomplete replication or aberrant MRRS on tumorigenesis, aging and disease.

  12. Revised Thorium Abundances for Lunar Red Spots

    Science.gov (United States)

    Hagerty, J. J.; Lawrence, D. J.; Elphic, R. C.; Feldman, W. C.; Vaniman, D. T.; Hawke, B. R.

    2005-01-01

    Lunar red spots are features on the nearside of the Moon that are characterized by high albedo and by a strong absorption in the ultraviolet. These red spots include the Gruithuisen domes, the Mairan domes, Hansteen Alpha, the southern portion of Montes Riphaeus, Darney Chi and Tau, Helmet, and an area near the Lassell crater. It has been suggested that many of the red spots are extrusive, nonmare, volcanic features that could be composed of an evolved lithlogy enriched in thorium. In fact, Hawke et al. used morphological characteristics to show that Hansteen Alpha is a nonmare volcanic construct. However, because the apparent Th abundances (6 - 7 ppm) were lower than that expected for evolved rock types, Hawke et al. concluded that Hansteen Alpha was composed of an unknown rock type. Subsequent studies by Lawrence et al. used improved knowledge of the Th spatial distribution for small area features on the lunar surface to revisit the interpretation of Th abundances at the Hansteen Alpha red spot. As part of their study, Lawrence et al. used a forward modeling technique to show that the Th abundance at Hansteen Alpha is not 6 ppm, but is more likely closer to 25 ppm, a value consistent with evolved lithologies. This positive correlation between the morphology and composition of Hansteen Alpha provides support for the presence of evolved lithologies on the lunar surface. It is possible, however, that Hansteen Alpha represents an isolated occurrence of non-mare volcanism. That is why we have chosen to use the forward modeling technique of Lawrence et al. to investigate the Th abundances at other lunar red spots, starting with the Gruithuisen domes. Additional information is included in the original extended abstract.

  13. Yield stress determination of a physical gel

    DEFF Research Database (Denmark)

    Hvidt, Søren

    2013-01-01

    Pluronic F127 solutions form gels in water with high elastic moduli. Pluronic gels can, however, only withstand small deformations and stresses. Different steady shear and oscillatory methods traditionally used to determine yield stress values are compared. The results show that the yield stresses...... values of these gels depend on test type and measurement time, and no absolute yield stress value can be determined for these physical gels....

  14. Hybrid Materials of Polymer Gels with Surfactants

    Institute of Scientific and Technical Information of China (English)

    Hu Yan; Kaoru Tsujii

    2005-01-01

    @@ 1 Introduction Polymer gels have been extensively studied[1~17] since the discovery of volume phase-transition of a gel by Tanaka[1~5]. As a unique soft material, gels attract much attention and are tried to be applied for drug-delivery systgems[6], actuators or chemo-mechanical devices[7~9] and so on. In particular, controlled-release of small molecules from a gel is now a subject of special interest[10].

  15. Study of Fricke gel dosimeter response for different gel quality

    Science.gov (United States)

    Cavinato, C. C.; Campos, L. L.

    2010-11-01

    The Fricke xylenol gel (FXG) dosimeter has been studied for application in radiotherapy because it is capable of to measure the spatial distribution of radiation doses. The dosimetry is based on the oxidation of ferrous (Fe2+) to ferric (Fe3+) ions radiation induced, related to the radiation dose. The gel material usually employed is the 300 Bloom gelatin, which is imported and very expensive in Brazil. Aiming to analyze the viability of to use a locally produced and low cost gel material, in this work the spectrophotometric responses of FXG solutions prepared using 270 Bloom gelatin commercially available and 300 Bloom gelatin imported were compared. The absorption spectra of solutions prepared with 5% by weight 270 and 300 Bloom gelatins non-irradiated and irradiated with 60Co gamma radiation in the dose range between 0.5 and 100 Gy were analysed, the dose-response curves were evaluated and the useful dose range was established. The obtained results indicate that the FXG solution prepared with 270 Bloom gelatin presents good performance, similar to that presented by the FXG solution prepared with 300 Bloom gelatin and its use can be recommended owing to the low cost and the availability in local market.

  16. A New Replication Norm for Psychology

    Directory of Open Access Journals (Sweden)

    Etienne P LeBel

    2015-10-01

    Full Text Available In recent years, there has been a growing concern regarding the replicability of findings in psychology, including a mounting number of prominent findings that have failed to replicate via high-powered independent replication attempts. In the face of this replicability “crisis of confidence”, several initiatives have been implemented to increase the reliability of empirical findings. In the current article, I propose a new replication norm that aims to further boost the dependability of findings in psychology. Paralleling the extant social norm that researchers should peer review about three times as many articles that they themselves publish per year, the new replication norm states that researchers should aim to independently replicate important findings in their own research areas in proportion to the number of original studies they themselves publish per year (e.g., a 4:1 original-to-replication studies ratio. I argue this simple approach could significantly advance our science by increasing the reliability and cumulative nature of our empirical knowledge base, accelerating our theoretical understanding of psychological phenomena, instilling a focus on quality rather than quantity, and by facilitating our transformation toward a research culture where executing and reporting independent direct replications is viewed as an ordinary part of the research process. To help promote the new norm, I delineate (1 how each of the major constituencies of the research process (i.e., funders, journals, professional societies, departments, and individual researchers can incentivize replications and promote the new norm and (2 any obstacles each constituency faces in supporting the new norm.

  17. 21 CFR 520.1452 - Moxidectin gel.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Moxidectin gel. 520.1452 Section 520.1452 Food and..., FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1452 Moxidectin gel. (a) Specifications. Each milliliter of gel contains 20 milligrams (2 percent) moxidectin. (b) Sponsor. See No....

  18. 21 CFR 866.4900 - Support gel.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Support gel. 866.4900 Section 866.4900 Food and... IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents § 866.4900 Support gel. (a) Identification. A support gel for clinical use is a device that consists of an agar or agarose preparation...

  19. Permeability of gels is set by the impulse applied on the gel

    NARCIS (Netherlands)

    Urbonaite, V.; Jongh, de H.H.J.; Linden, van der E.; Pouvreau, L.A.M.

    2015-01-01

    To better understand sensory perception of foods, water exudation studies on protein-based gels are of a high importance. It was aimed to study the interplay of gel coarseness and gel stiffness on water holding (WH) and water flow kinetics from the gel once force is applied onto the material. Ovalbu

  20. Data from Investigating Variation in Replicability: A “Many Labs” Replication Project

    Directory of Open Access Journals (Sweden)

    Richard A. Klein

    2014-04-01

    Full Text Available This dataset is from the Many Labs Replication Project in which 13 effects were replicated across 36 samples and over 6,000 participants. Data from the replications are included, along with demographic variables about the participants and contextual information about the environment in which the replication was conducted. Data were collected in-lab and online through a standardized procedure administered via an online link. The dataset is stored on the Open Science Framework website. These data could be used to further investigate the results of the included 13 effects or to study replication and generalizability more broadly.

  1. MALDI analysis of proteins after extraction from dissolvable ethylene glycol diacrylate cross-linked polyacrylamide gels.

    Science.gov (United States)

    Papasotiriou, Dimitrios G; Markoutsa, Stavroula; Gorka, Jan; Schleiff, Enrico; Karas, Michael; Meyer, Bjoern

    2013-09-01

    Although the extraction of intact proteins from polyacrylamide gels followed by mass spectrometric molecular mass determination has been shown to be efficient, there is room for alternative approaches. Our study evaluates ethylene glycol diacrylate, a cleavable cross-linking agent used for a new type of dissolvable gels. It attains an ester linkage that can be hydrolyzed in alkali conditions. The separation performance of the new gel system was tested by 1D and 2D SDS-PAGE using the outer chloroplast envelope of Pisum sativum as well as a soluble protein fraction of human lymphocytes, respectively. Gel spot staining (CBB), dissolving, and extracting were conducted using a custom-developed workflow. It includes protein extraction with an ammonia-SDS buffer followed by methanol treatment to remove acrylamide filaments. Necessary purification for MALDI-TOF analysis was implemented using methanol-chloroform precipitation and perfusion HPLC. Both cleaning procedures were applied to several standard proteins of different molecular weight as well as 'real' biological samples (8-75 kDa). The protein amounts, which had to be loaded on the gel to detect a peak in MALDI-TOF MS, were in the range of 0.1 to 5 μg, and the required amount increased with increasing mass.

  2. Gold nanoparticles grafted modified silica gel as a new stationary phase for separation and determination of steroid hormones by thin layer chromatography

    Directory of Open Access Journals (Sweden)

    Mitra Amoli-Diva

    2015-06-01

    Full Text Available A new thin layer chromatographic layer using gold nanoparticles grafted 3-triethoxysilyl propylamine modified silica gel (Au NPs-APTS modified silica gel was developed as a stationary phase for separation and determination of two steroid hormones, namely progesterone and testosterone. Acetone–n-hexane 25:75 (v/v was used as the mobile phase, and the results were compared with those obtained using plain (i.e., unmodified silica gel plates. Some chromatographic parameters used for separation of the two steroids on an Au NPs-APTS modified silica gel plate as well as on a plain silica gel plate, including ΔRF, separation factor (α, and resolution (RS, were evaluated and compared. The reproducibility of RF values was also determined by analysis of the two steroids in 7 consecutive days on both plates. Validity of the method was investigated, and a wide linear range of 1–200 ng per spot, and low detection limits of 0.16 ng and 0.13 ng per spot, low quantification limits of 0.51 ng and 0.40 ng per spot, and good precision (expressed as percent relative standard deviation lower than 3.1% and 2.7% were obtained for progesterone and testosterone, respectively. As the results revealed, the proposed method is rapid and sensitive, and it is applicable to separation and determination of progesterone and testosterone in biological matrices such as urine samples.

  3. Fluoride Rinses, Gels and Foams

    DEFF Research Database (Denmark)

    Twetman, Svante; Keller, Mette K

    2016-01-01

    AIM: The aim of this conference paper was to systematically review the quality of evidence and summarize the findings of clinical trials published after 2002 using fluoride mouth rinses, fluoride gels or foams for the prevention of dental caries. METHODS: Relevant papers were selected after...... an electronic search for literature published in English between 2003 and 2014. The included papers were assessed for their risk of bias and the results were narratively synthesized due to study heterogeneity. The quality of evidence was expressed according to GRADE. RESULTS: A total of 19 papers were included...... (6 on fluoride mouth rinse, 10 on fluoride gel and 3 on fluoride foam); 6 had a low risk of bias while 2 had a moderate risk. All fluoride measures appeared to be beneficial in preventing crown caries and reversing root caries, but the quality of evidence was graded as low for fluoride mouth rinse...

  4. Gel dosimetry for conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G. [Department of Physics of the University and INFN, Milan (Italy)]. e-mail: grazia.gambarini@mi.infn.it

    2005-07-01

    With the continuum development of conformal radio therapies, aimed at delivering high dose to tumor tissue and low dose to the healthy tissue around, the necessities has appeared of suitable improvement of dosimetry techniques giving the possibility of obtaining dose images to be compared with diagnostic images. Also if wide software has been developed for calculating dose distributions in the fields of various radiotherapy units, experimental verifications are necessary, in particular in the case of complex geometries in conformal radiotherapy. Gel dosimetry is a promising method for imaging the absorbed dose in tissue-equivalent phantoms, with the possibility of 3D reconstruction of the spatial dose distribution, with milli metric resolution. Optical imaging of gel dosimeters, based on visible light absorbance analysis, has shown to be a reliable technique for achieving dose distributions. (Author)

  5. Replication of M13 single—stranded DNA bearing a sitespecific ethenocytosine lesion by Escherichia coil cell extracts

    Institute of Scientific and Technical Information of China (English)

    WANGGE; PAULMDUNMAN; 等

    1997-01-01

    Previous investigation on the mutagenic effects of 3,N4-Ethenocytosine (εC),a nonpairing DNA lesion,revealed the existence of a novel SOS-independent inducible mutagenic mechanism in E.coli termed UVM for UV modulation of mutagenesis.To investigate whether UVM is mediated by an alteration of DNA replication,we have set up an in vitro replication system in which phage M13 viral single-stranded DNA bearing a single site-specific (εC) residue is replicated by soluble protein extracts from E.coli cells.Replication products were analyzed by agarose gel electrophoresis and the frequency of translesion synthesis was determined by restriction endonuclease analyses.Our data indicate that DNA replication is strongly inhibited by εC,but that translesion DNA synthesis does occur in about 14% of the replicated DNA molecules.These results are very similar to those observed previously in vivo,and suggest that this experimental system may be suitable for evaluating alterations in DNA replication in UVM-induced cells.

  6. Proteomic characterization of harvested pseudopodia with differential gel electrophoresis and specific antibodies.

    Science.gov (United States)

    Beckner, Marie E; Chen, Xuan; An, Jiyan; Day, Billy W; Pollack, Ian F

    2005-03-01

    Malignant gliomas (astrocytomas) are lethal tumors that invade the brain. Invasive cell migration is initiated by extension of pseudopodia into interstitial spaces. In this study, U87 glioma cells formed pseudopodia in vitro as cells pushed through 3 microm pores of polycarbonate membranes. Harvesting pseudopodia in a novel two-step method provided material for proteomic analysis. Differences in the protein profiles of pseudopodia and whole cells were found using differential gel electrophoresis (DIGE) and immunoblotting. Proteins from two-dimensional (2D) gels with M(R)'s of 20-100 kDa and pI's of 3.0-10.0 were identified by peptide mass fingerprinting analysis using mass spectrometry. For DIGE, lysates of pseudopodia and whole cells were each labeled with electrophilic forms of fluorescent dyes, Cy3 or Cy5, and analyzed as mixtures. Analysis was repeated with reciprocal labeling. Differences in protein distributions were detected by manual inspection and computer analysis. Topographical digital maps of the scanned gels were used for algorithmic spot matching, normalization of background, quantifying spot differences, and elimination of artifacts. Pseudopodial proteins in Coomassie-stained 2D gels included isoforms of glycolytic enzymes as the largest group, seven of 24 proteins. Peptide mass fingerprint analysis of DIGE gels demonstrated increased isoforms of annexin (Anx) I, AnxII, enolase, pyruvate kinase, and aldolase, and decreased mitochondrial manganese superoxide dismutase and transketolase in pseudopodia. Specific antibodies showed restricted immunoreactivity of the hepatocyte growth factor (HGF) alpha chain to pseudopodia, indicating localization of its active form. Met (the HGF receptor), actin, and total AnxI were increased in pseudopodial lysates on immunoblots. Increased constituents of the pseudopodial proteome in glioma cells, identified in this study as actin, HGF, Met, and isoforms of AnxI, AnxII, and several glycolytic enzymes, represent

  7. Unexpected Inflammatory Effects of Intravaginal Gels (Universal Placebo Gel and Nonoxynol-9 on the Upper Female Reproductive Tract: A Randomized Crossover Study.

    Directory of Open Access Journals (Sweden)

    Karen Smith-McCune

    Full Text Available Intravaginal anti-HIV microbicides could provide women with a self-controlled means for HIV prevention, but results from clinical trials have been largely disappointing. We postulated that unrecognized effects of intravaginal gels on the upper female reproductive tract might contribute to the lower-than-expected efficacy of HIV microbicides. Our objective was to study the effects of intravaginal gels on the immune microenvironment of the cervix and uterus. In this randomized crossover study, 27 healthy female volunteers used a nightly application of intravaginal nonoxynol-9 (N9 gel as a "failed" microbicide or the universal placebo gel (UPG as a "safe" gel (intervention cycles, or nothing (control cycle from the end of menses to the mid-luteal phase. At a specific time-point following ovulation, all participants underwent sample collection for measurements of T-cell phenotypes, gene expression, and cytokine/chemokine protein concentrations from 3 anatomic sites above the vagina: the cervical transformation zone, the endocervix and the endometrium. We used hierarchical statistical models to estimate mean (95% CI intervention effects, for N9 and UPG relative to control. Exposure to N9 gel and UPG generated a common "harm signal" that included transcriptional up-regulation of inflammatory genes chemokine (C-C motif ligand 20 (macrophage inflammatory factor-3alpha and interleukin 8 in the cervix, decreased protein concentrations of secretory leukocyte protease inhibitor, and transcriptional up-regulation of inflammatory mediators glycodelin-A and osteopontin in the endometrium. These results need to be replicated with a larger sample, but underscore the need to consider the effects of microbicide agents and gel excipients on the upper female reproductive tract in studies of vaginal microbicides.

  8. Replication forks reverse at high frequency upon replication stress in Physarum polycephalum.

    Science.gov (United States)

    Maric, Chrystelle; Bénard, Marianne

    2014-12-01

    The addition of hydroxyurea after the onset of S phase allows replication to start and permits the successive detecting of replication-dependent joint DNA molecules and chicken foot structures in the synchronous nuclei of Physarum polycephalum. We find evidence for a very high frequency of reversed replication forks upon replication stress. The formation of these reversed forks is dependent on the presence of joint DNA molecules, the impediment of the replication fork progression by hydroxyurea, and likely on the propensity of some replication origins to reinitiate replication to counteract the action of this compound. As hydroxyurea treatment enables us to successively detect the appearance of joint DNA molecules and then of reversed replication forks, we propose that chicken foot structures are formed both from the regression of hydroxyurea-frozen joint DNA molecules and from hydroxyurea-stalled replication forks. These experiments underscore the transient nature of replication fork regression, which becomes detectable due to the hydroxyurea-induced slowing down of replication fork progression.

  9. Sol-gel derived ceramics

    OpenAIRE

    1990-01-01

    The synthesis of ceramic raw materials has become an important factor in ceramic technologies. The increasing demands to the performance of ceramic compounds has caused increased activities for the preparation of tailor-made raw materials. Amongst a variety of new syntheses like flame pyrolysis, reactive spray drying, plasma or laser assisted techniques, the sol-gel process plays an important and increasing role. The process describes the building up of an inorganic (in general an oxide) netw...

  10. The Sol-Gel Process

    OpenAIRE

    Khalid Suliman Aboodh

    2015-01-01

    Abstract An increasingly important application of liquid jets is the disintegration of the jet to form droplets of liquid containing nuclear fuel. These droplets are then dried and sintered to form ceramic micro spheres for use in fuel elements in nuclear reactors. The total operations required to form the droplets convert them to solids and fire them to ceramic bodies comprise what are known as Sol-Gel processes Reference 13.

  11. Proteomic Comparison of Two-Dimensional Gel Electrophoresis Pro files from Human Lung Squamous Carcinoma and Normal Bronchial Epithelial Tissues

    Institute of Scientific and Technical Information of China (English)

    Cui Li; Ping Chen; Jingyun Xie; Songping Liang; Xianquan Zhan; Maoyu Li; Xiaoying Wu; Feng Li; Jianling Li; Zhiqiang Xiao; Zhuchu Chen; Xueping Feng

    2003-01-01

    Differential proteome profiles of human lung squamous carcinoma tissue compared to paired tumor-adjacent normal bronchial epithelial tissue were established and analyzed by means of immobilized pH gradient-based two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). The results showed that well-resolved, reproducible 2-DE patterns of human lung squamous carcinoma and adjacent normal bronchial epithelial tissues were obtained under the condition of 0.75-ug protein-load. The average deviation of spot position was 0.733+0.101 mm in IEF direction, and 0.925+0.207 mm in SDS-PAGE direction. For tumor tissue, a total of 1241±88 spots were detected, 987±65 spots were matched with an average matching rate of 79.5%. For control, a total of 1190+72 spots were detected, and 875±48 spots were matched with an average matching rate of 73.5%. A total of 864±34 spots were matched between tumors and controls.Forty-three differential proteins were characterized: some proteins were related to oncogenes, and others involved in the regulation of cell cycle and signal transduction. It is suggested that the differential proteomic approach is valuable for mass identification of differentially expressed proteins involved in lung carcinogenesis.These data will be used to establish human lung cancer proteome database to further study human lung squamous carcinoma.

  12. The gel electrophoresis markup language (GelML) from the Proteomics Standards Initiative.

    Science.gov (United States)

    Gibson, Frank; Hoogland, Christine; Martinez-Bartolomé, Salvador; Medina-Aunon, J Alberto; Albar, Juan Pablo; Babnigg, Gyorgy; Wipat, Anil; Hermjakob, Henning; Almeida, Jonas S; Stanislaus, Romesh; Paton, Norman W; Jones, Andrew R

    2010-09-01

    The Human Proteome Organisation's Proteomics Standards Initiative has developed the GelML (gel electrophoresis markup language) data exchange format for representing gel electrophoresis experiments performed in proteomics investigations. The format closely follows the reporting guidelines for gel electrophoresis, which are part of the Minimum Information About a Proteomics Experiment (MIAPE) set of modules. GelML supports the capture of metadata (such as experimental protocols) and data (such as gel images) resulting from gel electrophoresis so that laboratories can be compliant with the MIAPE Gel Electrophoresis guidelines, while allowing such data sets to be exchanged or downloaded from public repositories. The format is sufficiently flexible to capture data from a broad range of experimental processes, and complements other PSI formats for MS data and the results of protein and peptide identifications to capture entire gel-based proteome workflows. GelML has resulted from the open standardisation process of PSI consisting of both public consultation and anonymous review of the specifications.

  13. A quantitative model of DNA replication in Xenopus embryos: reliable replication despite stochasticity

    Science.gov (United States)

    Cheng-Hsin Yang, Scott; Bechhoefer, John

    2008-03-01

    DNA synthesis in Xenopus frog embryos initiates stochastically in time at many sites (origins) along the chromosome. Stochastic initiation implies fluctuations in the replication time and may lead to cell death if replication takes longer than the cell cycle time (˜ 25 min.). Surprisingly, although the typical replication time is about 20 min., in vivo experiments show that replication fails to complete only about 1 in 250 times. How is replication timing accurately controlled despite the stochasticity? Biologists have proposed two mechanisms: the first uses a regular spatial distribution of origins, while the second uses randomly located origins but increases their probability of initiation as the cell cycle proceeds. Here, we show that both mechanisms yield similar end-time distributions, implying that regular origin spacing is not needed for control of replication time. Moreover, we show that the experimentally inferred time-dependent initiation rate satisfies the observed low failure probability and nearly optimizes the use of replicative proteins.

  14. Plasma spot welding of ferritic stainless steels

    Directory of Open Access Journals (Sweden)

    Lešnjak, A.

    2002-06-01

    Full Text Available Plasma spot welding of ferritic stainless steels is studied. The study was focused on welding parameters, plasma and shielding gases and the optimum welding equipment. Plasma-spot welded overlap joints on a 0.8 mm thick ferritic stainless steel sheet were subjected to a visual examination and mechanical testing in terms of tension-shear strength. Several macro specimens were prepared. Plasma spot welding is suitable to use the same gas as shielding gas and as plasma gas, i.e., a 98 % Ar/2 % H 2 gas mixture. Tension-shear strength of plasma-spot welded joints was compared to that of resistance-spot welded joints. It was found that the resistance welded joints withstand a somewhat stronger load than the plasma welded joints due to a larger weld spot diameter of the former. Strength of both types of welded joints is approximately the same.

    El artículo describe el proceso de soldeo de aceros inoxidables ferríticos por puntos con plasma. La investigación se centró en el establecimiento de los parámetros óptimos de la soldadura, la definición del gas de plasma y de protección más adecuado, así como del equipo óptimo para la realización de la soldadura. Las uniones de láminas de aceros inoxidables ferríticos de 0,8 mm de espesor, soldadas a solape por puntos con plasma, se inspeccionaron visualmente y se ensayaron mecánicamente mediante el ensayo de cizalladura por tracción. Se realizaron macro pulidos. Los resultados de la investigación demostraron que la solución más adecuada para el soldeo por puntos con plasma es elegir el mismo gas de plasma que de protección. Es decir, una mezcla de 98 % de argón y 2 % de hidrógeno. La resistencia a la cizalladura por tracción de las uniones soldadas por puntos con plasma fue comparada con la resistencia de las uniones soldadas por resistencia por puntos. Se llegó a la conclusión de que las uniones soldadas por resistencia soportan una carga algo mayor que la uniones

  15. Isolation and characterization of an antifungal peptide with antiproliferative activity from seeds of Phaseolus vulgaris cv. 'Spotted Bean'.

    Science.gov (United States)

    Wang, H X; Ng, T B

    2007-02-01

    A 7.3-kDa antifungal peptide with an N-terminal sequence exhibiting remarkable homology to defensins from other leguminous plants was isolated from Phaseolus vulgaris cv. 'Spotted Bean'. The isolation procedure involved ion exchange chromatography on O-diethylaminoethyl (DEAE) cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on SP-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. The peptide was unadsorbed on DEAE-cellulose and adsorbed on Affi-gel blue gel and SP-Sepharose. It exerted an antifungal action on Fusarium oxysporum and Mycosphaerella arachidicola. It inhibited mycelial growth in F. oxysporum with an IC(50) value of 1.8 microM. It suppressed [methyl-(3)H]-thymidine incorporation by leukemia L1210 cells and MBL2 cells with an IC(50) value of 4.0 and 9.0 microM, respectively. There was no effect on HIV-1 reverse transcriptase activity when the peptide was tested up to 0.1 mM.

  16. Targeting DNA Replication Stress for Cancer Therapy

    Science.gov (United States)

    Zhang, Jun; Dai, Qun; Park, Dongkyoo; Deng, Xingming

    2016-01-01

    The human cellular genome is under constant stress from extrinsic and intrinsic factors, which can lead to DNA damage and defective replication. In normal cells, DNA damage response (DDR) mediated by various checkpoints will either activate the DNA repair system or induce cellular apoptosis/senescence, therefore maintaining overall genomic integrity. Cancer cells, however, due to constitutive growth signaling and defective DDR, may exhibit “replication stress” —a phenomenon unique to cancer cells that is described as the perturbation of error-free DNA replication and slow-down of DNA synthesis. Although replication stress has been proven to induce genomic instability and tumorigenesis, recent studies have counterintuitively shown that enhancing replicative stress through further loosening of the remaining checkpoints in cancer cells to induce their catastrophic failure of proliferation may provide an alternative therapeutic approach. In this review, we discuss the rationale to enhance replicative stress in cancer cells, past approaches using traditional radiation and chemotherapy, and emerging approaches targeting the signaling cascades induced by DNA damage. We also summarize current clinical trials exploring these strategies and propose future research directions including the use of combination therapies, and the identification of potential new targets and biomarkers to track and predict treatment responses to targeting DNA replication stress. PMID:27548226

  17. Oncogene v-jun modulates DNA replication.

    Science.gov (United States)

    Wasylyk, C; Schneikert, J; Wasylyk, B

    1990-07-01

    Cell transformation leads to alterations in both transcription and DNA replication. Activation of transcription by the expression of a number of transforming oncogenes is mediated by the transcription factor AP1 (Herrlich & Ponta, 1989; Imler & Wasylyk, 1989). AP1 is a composite transcription factor, consisting of members of the jun and fos gene-families. c-jun and c-fos are progenitors of oncogenes, suggestion that an important transcriptional event in cell transformation is altered activity of AP1, which may arise either indirectly by oncogene expression or directly by structural modification of AP1. We report here that the v-jun oncogene and its progenitor c-jun, as fusion proteins with the lex-A-repressor DNA binding domain, can activate DNA replication from the Polyoma virus (Py) origin of replication, linked to the lex-A operator. The transcription-activation region of v-jun is required for activation of replication. When excess v-jun is expressed in the cell, replication is inhibited or 'squelched'. These results suggest that one consequence of deregulated jun activity could be altered DNA replication and that there are similarities in the way v-jun activates replication and transcription.

  18. Targeting DNA Replication Stress for Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    2016-08-01

    Full Text Available The human cellular genome is under constant stress from extrinsic and intrinsic factors, which can lead to DNA damage and defective replication. In normal cells, DNA damage response (DDR mediated by various checkpoints will either activate the DNA repair system or induce cellular apoptosis/senescence, therefore maintaining overall genomic integrity. Cancer cells, however, due to constitutive growth signaling and defective DDR, may exhibit “replication stress” —a phenomenon unique to cancer cells that is described as the perturbation of error-free DNA replication and slow-down of DNA synthesis. Although replication stress has been proven to induce genomic instability and tumorigenesis, recent studies have counterintuitively shown that enhancing replicative stress through further loosening of the remaining checkpoints in cancer cells to induce their catastrophic failure of proliferation may provide an alternative therapeutic approach. In this review, we discuss the rationale to enhance replicative stress in cancer cells, past approaches using traditional radiation and chemotherapy, and emerging approaches targeting the signaling cascades induced by DNA damage. We also summarize current clinical trials exploring these strategies and propose future research directions including the use of combination therapies, and the identification of potential new targets and biomarkers to track and predict treatment responses to targeting DNA replication stress.

  19. A whole genome RNAi screen identifies replication stress response genes.

    Science.gov (United States)

    Kavanaugh, Gina; Ye, Fei; Mohni, Kareem N; Luzwick, Jessica W; Glick, Gloria; Cortez, David

    2015-11-01

    Proper DNA replication is critical to maintain genome stability. When the DNA replication machinery encounters obstacles to replication, replication forks stall and the replication stress response is activated. This response includes activation of cell cycle checkpoints, stabilization of the replication fork, and DNA damage repair and tolerance mechanisms. Defects in the replication stress response can result in alterations to the DNA sequence causing changes in protein function and expression, ultimately leading to disease states such as cancer. To identify additional genes that control the replication stress response, we performed a three-parameter, high content, whole genome siRNA screen measuring DNA replication before and after a challenge with replication stress as well as a marker of checkpoint kinase signalling. We identified over 200 replication stress response genes and subsequently analyzed how they influence cellular viability in response to replication stress. These data will serve as a useful resource for understanding the replication stress response.

  20. Study on the micro-replication of shark skin

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Direct replication of creatural scarfskins to form biomimetic surfaces with relatively vivid morphology is a new attempt of the bio-replicated forming technology at animal body. Taking shark skins as the replication templates, and the micro-embossing and micro-molding as the material forming methods, the micro-replicating technology of the outward morphology on shark skins was demonstrated. The preliminary analysis on replication precision indicates that the bio-replicated forming technology can replicate the outward morphology of the shark scales with good precision, which validates the application of the bio-replicated forming technology in the direct morphology replication of the firm creatural scarfskins.

  1. 7 CFR 27.93 - Bona fide spot markets.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Bona fide spot markets. 27.93 Section 27.93... REGULATIONS COTTON CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Spot Markets § 27.93 Bona fide spot markets. The following markets have been determined, after investigation, and are...

  2. 7 CFR 28.421 - Good Middling Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Good Middling Spotted Color. 28.421 Section 28.421 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Color. Good Middling Spotted Color is color which is better than Strict Middling Spotted Color....

  3. 7 CFR 28.426 - Strict Good Ordinary Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Strict Good Ordinary Spotted Color. 28.426 Section 28.426 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Spotted Color. Strict Good Ordinary Spotted Color is color which is within the range represented by a...

  4. 7 CFR 28.424 - Strict Low Middling Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Strict Low Middling Spotted Color. 28.424 Section 28.424 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Spotted Color. Strict Low Middling Spotted Color is color which is within the range represented by a...

  5. Discovery of feature-based hot spots using supervised clustering

    Science.gov (United States)

    Ding, Wei; Stepinski, Tomasz F.; Parmar, Rachana; Jiang, Dan; Eick, Christoph F.

    2009-07-01

    Feature-based hot spots are localized regions where the attributes of objects attain high values. There is considerable interest in automatic identification of feature-based hot spots. This paper approaches the problem of finding feature-based hot spots from a data mining perspective, and describes a method that relies on supervised clustering to produce a list of hot spot regions. Supervised clustering uses a fitness function rewarding isolation of the hot spots to optimally subdivide the dataset. The clusters in the optimal division are ranked using the interestingness of clusters that encapsulate their utility for being hot spots. Hot spots are associated with the top ranked clusters. The effectiveness of supervised clustering as a hot spot identification method is evaluated for four conceptually different clustering algorithms using a dataset describing the spatial distribution of ground ice on Mars. Clustering solutions are visualized by specially developed raster approximations. Further assessment of the ability of different algorithms to yield hot spots is performed using raster approximations. Density-based clustering algorithm is found to be the most effective for hot spot identification. The results of the hot spot discovery by supervised clustering are comparable to those obtained using the G* statistic, but the new method offers a high degree of automation, making it an ideal tool for mining large datasets for the existence of potential hot spots.

  6. Replicated Data Management for Mobile Computing

    CERN Document Server

    Douglas, Terry

    2008-01-01

    Managing data in a mobile computing environment invariably involves caching or replication. In many cases, a mobile device has access only to data that is stored locally, and much of that data arrives via replication from other devices, PCs, and services. Given portable devices with limited resources, weak or intermittent connectivity, and security vulnerabilities, data replication serves to increase availability, reduce communication costs, foster sharing, and enhance survivability of critical information. Mobile systems have employed a variety of distributed architectures from client-server

  7. Duration of Fipronil and Imidacloprid Gel Baits Toxicity against Blattella germanica Strains of Iran

    Directory of Open Access Journals (Sweden)

    H Nasirian

    2007-12-01

    Full Text Available The current study was conducted to investigate the duration of fipronil and imidacloprid gel baits toxicity against Ger-man cockroach strains in Iran during 2003-2004. In order to conduct this study, nine German cockroach strains were used. Newly emerged adult male German cockroaches starved for one scotophase (12 h, and ingested fipronil and imidacloprid gel baits for 2 h. After the given time was over, the bait was removed and replaced with mouse pellet. Mortality was re-corded at 12 intervals for 144 h (6 days. Mortality data of the replicates were pooled and was tested using probit analysis. Both gel baits were toxic to adult male German cockroaches. In the ingested bait method, the susceptible strain showed LT50 of 47.1 and 11.3 h for fipronil and imidacloprid gel baits, respectively, and the average LT90 was 74.2 and 19.3 h, respec¬tively. LT50 of the feral German cockroach strains varied 14.9 h from 30.5 to 45.4 h and 4.4 h from 12.4 to 16.8 h for fipronil and imidacloprid gel baits, respectively. All German cockroach strains showed a similar susceptibility to fipronil and imidacloprid gel baits, compared with the susceptible laboratory strain. The steep slopes of ingested bait mortality curves indicated that the feral German cockroach strains were homogenous to fipronil and imidacloprid ingested gel baits. These results suggest that fipronil and imidacloprid gel baits appear to have considerable potential as a bait for insecticide-resistant strains of German cockroach.

  8. Duration of Fipronil and Imidacloprid Gel Baits Toxicity against Blattella germanica Strains of Iran

    Directory of Open Access Journals (Sweden)

    H Nasirian

    2007-11-01

    Full Text Available The current study was conducted to investigate the duration of fipronil and imidacloprid gel baits toxicity against Ger-man cockroach strains in Iran during 2003-2004. In order to conduct this study, nine German cockroach strains were used. Newly emerged adult male German cockroaches starved for one scotophase (12 h, and ingested fipronil and imidacloprid gel baits for 2 h. After the given time was over, the bait was removed and replaced with mouse pellet. Mortality was re-corded at 12 intervals for 144 h (6 days. Mortality data of the replicates were pooled and was tested using probit analysis. Both gel baits were toxic to adult male German cockroaches. In the ingested bait method, the susceptible strain showed LT50 of 47.1 and 11.3 h for fipronil and imidacloprid gel baits, respectively, and the average LT90 was 74.2 and 19.3 h, respec¬tively. LT50 of the feral German cockroach strains varied 14.9 h from 30.5 to 45.4 h and 4.4 h from 12.4 to 16.8 h for fipronil and imidacloprid gel baits, respectively. All German cockroach strains showed a similar susceptibility to fipronil and imidacloprid gel baits, compared with the susceptible laboratory strain. The steep slopes of ingested bait mortality curves indicated that the feral German cockroach strains were homogenous to fipronil and imidacloprid ingested gel baits. These results suggest that fipronil and imidacloprid gel baits appear to have considerable potential as a bait for insecticide-resistant strains of German cockroach.

  9. Gel fire suppressants for controlling underground heating

    Institute of Scientific and Technical Information of China (English)

    HU Sheng-gen; XUE Sheng

    2011-01-01

    One of the major safety issues in coal mining is heatings and the resultant spontaneous combustion in underground coal mines.CSIRO researchers have developed a number of polymer gels suitable for controlling heatings in coal mines.These gels were developed to meet strict selection criteria including easy preparation,no or low toxicity,controllable gelation time,adaptable to mine water chemistry,adjustable viscosity,relatively long gel life,thermally and chemically stable and low cost.The HPAM-Aluminum Citrate gel system was identified to be the most favourable gel system for fire suppression in underground coal mines.These gels can be applied to the areas undergoing coal heating or gas leakage at a controllable gelation time and impermeable gel barriers can be formed in the areas to block ingress of air.

  10. Consolidation of Inorganic Precipitated Silica Gel

    Directory of Open Access Journals (Sweden)

    Matthias Kind

    2011-08-01

    Full Text Available Colloidal gels are possible intermediates in the generation of highly porous particle systems. In the production process the gels are fragmented after their formation. These gel fragments compact to particles whose application-technological properties are determined by their size and porosity. In the case of precipitated silica gels, this consolidation process depends on temperature and pH, among other parameters. It is shown that these dependencies can be characterized by oedometer measurements. Originally, the oedometer test (one-dimensional compression test stemmed from soil mechanics. It has proven to be an interesting novel examination method for gels. Quantitative data of the time-dependent shrinkage of gel samples can be obtained. The consolidation of the gels shows a characteristic dependence on the above parameters.

  11. RNA-dependent RNA polymerase 6 delays accumulation and precludes meristem invasion of a viroid that replicates in the nucleus.

    Science.gov (United States)

    Di Serio, Francesco; Martínez de Alba, Angel-Emilio; Navarro, Beatriz; Gisel, Andreas; Flores, Ricardo

    2010-03-01

    The detection of viroid-derived small RNAs (vd-sRNAs) similar to the small interfering RNAs (siRNAs, 21 to 24 nucleotides [nt]) in plants infected by nuclear-replicating members of the family Pospiviroidae (type species, Potato spindle tuber viroid [PSTVd]) indicates that they are inducers and targets of the RNA-silencing machinery of their hosts. RNA-dependent RNA polymerase 6 (RDR6) catalyzes an amplification circuit producing the double-stranded precursors of secondary siRNAs. Recently, the role of RDR6 in restricting systemic spread of certain RNA viruses and precluding their invasion of the apical growing tip has been documented using RDR6-silenced Nicotiana benthamiana (NbRDR6i) plants. Here we show that RDR6 is also engaged in regulating PSTVd levels: accumulation of PSTVd genomic RNA was increased in NbRDR6i plants with respect to the wild-type controls (Nbwt) early in infection, whereas this difference decreased or disappeared in later infection stages. Moreover, in situ hybridization revealed that RDR6 is involved in restricting PSTVd access in floral and vegetative meristems, thus providing firm genetic evidence for an antiviroid RNA silencing mechanism. RNA gel blot hybridization and deep sequencing showed in wt and RDR6i backgrounds that PSTVd sRNAs (i) accumulate to levels paralleling their genomic RNA, (ii) display similar patterns with prevailing 22- or 21-nt plus-strand species, and (iii) adopt strand-specific hot spot profiles along the genomic RNA. Therefore, the surveillance mechanism restraining entry of some RNA viruses into meristems likely also controls PSTVd access in N. benthamiana. Unexpectedly, deep sequencing also disclosed in NbRDR6i plants a profile of RDR6-derived siRNA dominated by 21-nt plus-strand species mapping within a narrow window of the hairpin RNA stem expressed transgenically for silencing RDR6, indicating that minus-strand siRNAs silencing the NbRDR6 mRNA represent a minor fraction of the total siRNA population.

  12. Automated Spot Weld Inspection using Infrared Thermography

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jian [ORNL; Zhang, Wei [ORNL; Yu, Zhenzhen [ORNL; Feng, Zhili [ORNL

    2012-01-01

    An automated non-contact and non-destructive resistance spot weld inspection system based on infrared (IR) thermography was developed for post-weld applications. During inspection, a weld coupon was heated up by an auxiliary induction heating device from one side of the weld, while the resulting thermal waves on the other side were observed by an IR camera. The IR images were analyzed to extract a thermal signature based on normalized heating time, which was then quantitatively correlated to the spot weld nugget size. The use of normalized instead of absolute IR intensity was found to be useful in minimizing the sensitivity to the unknown surface conditions and environment interference. Application of the IR-based inspection system to different advanced high strength steels, thickness gauges and coatings were discussed.

  13. Brazilian spotted fever: a reemergent zoonosis

    Directory of Open Access Journals (Sweden)

    H. Greca

    2008-01-01

    Full Text Available Brazilian spotted fever is caused by the bacterium Rickettsia rickettsii, which is the most pathogenic species of the spotted-fever rickettsiae group and is transmitted by the bite of infected ticks. Amblyomma cajennense is the most important tick species involved in the cycle of this zoonosis in Brazil as it presents low host specificity, great number of natural reservoirs and wide geographic distribution. It was first described in the state of São Paulo in 1929 and later in Rio de Janeiro, Minas Gerais and Bahia. The number of cases decreased in the 1940's with the development of new plague control techniques and antibiotics. In the last decades, the number of new cases has increased. The current review aimed at reporting some of the epidemiological and public health aspects of this reemergent disease with new foci, mainly in the southeastern region of Brazil.

  14. Spot foreign exchange market and time series

    Science.gov (United States)

    Petroni, F.; Serva, M.

    2003-08-01

    We investigate high frequency price dynamics in foreign exchange market using data from Reuters information system (the dataset has been provided to us by Olsen and Associates). In our analysis we show that a naïve approach to the definition of price (for example using the spot mid price) may lead to wrong conclusions on price behavior as for example the presence of short term correlations for returns. For this purpose we introduce an algorithm which only uses the non arbitrage principle to estimate real prices from the spot ones. The new definition leads to returns which are not affected by spurious correlations. Furthermore, any apparent information (defined by using Shannon entropy) contained in the data disappears.

  15. A case of Rocky Mountain spotted fever.

    Science.gov (United States)

    Rubel, Barry S

    2007-01-01

    Rocky Mountain spotted fever is a serious, generalized infection that is spread to humans through the bite of infected ticks. It can be lethal but it is curable. The disease gets its name from the Rocky Mountain region where it was first identified in 1896. The fever is caused by the bacterium Rickettsia rickettsii and is maintained in nature in a complex life cycle involving ticks and mammals. Humans are considered to be accidental hosts and are not involved in the natural transmission cycle of this pathogen. The author examined a 47-year-old woman during a periodic recall appointment. The patient had no dental problems other than the need for routine prophylaxis but mentioned a recent problem with swelling of her extremities with an accompanying rash and general malaise and soreness in her neck region. Tests were conducted and a diagnosis of Rocky Mountain spotted fever was made.

  16. Downhole drilling spotting fluid composition and method

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, J.R.; Campbell, G.J.

    1991-03-26

    This paper discusses a spotting fluid concentrate composition suitable for use in downhole drilling operations in a pill for releasing periodically stuck drill string. It comprises glycerophosphoric acid ester; a polyacyloxy polycarboxylic acid ester of monoglycerides, diglycerides and mixtures thereof; an optional viscosifying agent for increasing the viscosity of the dispersion; and an optional sealing agent for preventing diffusion of water into the downhole formation. This patent also describes a method for lubricating a downhole well drilling operation. It comprises mixing a spotting fluid concentrate composition comprising glycerophosphoric acid ester, a polyacyloxy polycarboxylic acid ester of monoglycerides, diglycerides and mixtures thereof, an optional viscosifying agent and an optional sealing agent with drilling mud; and circulating the mud mixture through the well.

  17. Research Hot Spots of Black Peanut

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Taking the research papers on black peanut in National Knowledge Infrastructure(CNKI)as data sources,we determine the research hot spots on black peanut using word frequency analysis,and analyze the main research directions that change over the years.The results show that the relevant researches on black peanut are mainly concentrated in six themes(study of varieties,physiological property,cultivation management,development prospects,relationship with agriculture,and molecular level);varieties,physiology,cultivation and other aspects are the focus of current research hot spots;the researches on selection and breeding of variety and various physiological and ecological mechanisms,still need a breakthrough.

  18. spots de campaña

    Directory of Open Access Journals (Sweden)

    Julio Juárez Gámiz

    2007-01-01

    publicidad política en televisión. Ilustrado por los spots televisivos, el debate se ha centrado en el alto costo que representa para los contribuyentes, a través de los partidos políticos, la producción y transmisión de estos mensajes. El presente trabajo consiste en un análisis de contenido de una muestra de spots transmitidos por las tres principales fuerzas electorales en México durante la campaña presidencial de 2006. El objetivo es identificar, de manera sistemática, características particulares en el formato y contenido de estos mensajes a la luz de su función persuasiva e informativa.

  19. Jupiter Great Red Spot and White Ovals

    Science.gov (United States)

    1979-01-01

    This photo of Jupiter was taken by Voyager 1 on March 1, 1979. The spacecraft was 3 million miles (5 million kilometers) from Jupiter at the time. The photo shows Jupiter's Great Red Spot (upper right) and the turbulent region immediately to the west. At the middle right of the frame is one of several white ovals seen on Jupiter from Earth. The structure in every feature here is far better than has ever been seen from any telescopic observations. The Red Spot and the white oval both reveal intricate and involved structure. The smallest details that can be seen in this photo are about 55 miles (95 kilometers) across. JPL manages and controls the Voyager project for NASA's Office of Space Science.

  20. Jupiter's Great Red Spot and White Ovals

    Science.gov (United States)

    1979-01-01

    This photo of Jupiter was taken by Voyager 1 on the evening of March 1, 1979, from a distance of 2.7 million miles (4.3 million kilometers). The photo shows Jupiter's Great Red Spot (top) and one of the white ovals than can be seen in Jupiter's atmosphere from Earth. The white ovals were seen to form in 1939, and 1940, and have remained more or less constant ever since. None of the structure and detail evident in these features have ever been seen from Earth. The Great Red Spot is three times as large as Earth. Also evident in the picture is a great deal of atmospheric detail that will require further study for interpretation. The smallest details that can be seen in this picture are about 45 miles (80 kilometers across. JPL manages and controls the Voyager project for NASA's Office of Space Science.

  1. Laser induced single spot oxidation of titanium

    Energy Technology Data Exchange (ETDEWEB)

    Jwad, Tahseen, E-mail: taj355@bham.ac.uk; Deng, Sunan; Butt, Haider; Dimov, S.

    2016-11-30

    Highlights: • A new high resolution laser induced oxidation (colouring) method is proposed (single spot oxidation). • The method is applied to control oxide films thicknesses and hence colours on titanium substrates in micro-scale. • The method enable imprinting high resolution coloured image on Ti substrate. • Optical and morphological periodic surface structures are also produced by an array of oxide spots using the proposed method. • Colour coding of two colours into one field is presented. - Abstract: Titanium oxides have a wide range of applications in industry, and they can be formed on pure titanium using different methods. Laser-induced oxidation is one of the most reliable methods due to its controllability and selectivity. Colour marking is one of the main applications of the oxidation process. However, the colourizing process based on laser scanning strategies is limited by the relative large processing area in comparison to the beam size. Single spot oxidation of titanium substrates is proposed in this research in order to increase the resolution of the processed area and also to address the requirements of potential new applications. The method is applied to produce oxide films with different thicknesses and hence colours on titanium substrates. High resolution colour image is imprinted on a sheet of pure titanium by converting its pixels’ colours into laser parameter settings. Optical and morphological periodic surface structures are also produced by an array of oxide spots and then analysed. Two colours have been coded into one field and the dependencies of the reflected colours on incident and azimuthal angles of the light are discussed. The findings are of interest to a range of application areas, as they can be used to imprint optical devices such as diffusers and Fresnel lenses on metallic surfaces as well as for colour marking.

  2. Acuerdos de comercio internacional spot de electricidad

    OpenAIRE

    Mario Ibarburu

    2012-01-01

    International power trade requires the existence of regulation and a formal agreement between the countries. In South America power trade is mainly a bilateral spot trade decided by system operators, at prices resulting from rules determined in long term agreements between countries. The institutional framework is quite different from other regions’, where the goal is the existence of a single integrated energy market. Very soon Uruguay will be strongly interconnected with its two neighbors, ...

  3. Characterization of LIL laser UV focal spot

    Energy Technology Data Exchange (ETDEWEB)

    Mangeant, M.; Dubois, J.L.; Behar, G.; Arroyo, P.; Durand, V.; Lahonde, C. [CEA - Centre d' Etudes Scientifiques et Techniques d' Aquitaine, CESTA/DLP, 33 - Le Barp (France)

    2006-06-15

    One way to get the fusion of hydrogen in laboratory consists in heating and compressing a DT fuel capsule by using a laser. To reach this aim requires a new generation of high power laser facility. Cea (French board for atomic energy) is developing for this purpose a new 240 laser line facility, the LMJ facility. The LIL which is the prototype of four LMJ laser lines is operational now. In order to confirm the technical choices, a systematic characterization of LIL was carried out. A particular effort has been provided to measure the 3{omega} high energy focal spot (1.5 kJ/700 ps and 5 ns for one beam) and the synchronization of laser beams onto the target, which are key issues for the plasma production. An experimental device, SAT-3{omega} (a 3{omega} laser focal spot analysis) has been designed to perform these measures. That diagnostic which is located at the end of the laser lines delivered its first results during the 2004 quadruplet qualification campaigns. The near field imaging showed no diaphony and vignetting. Low power spots allowed us to control we had no ghost. The energy measurement quality showed the photometric transfer function was perfectly known. Our caustic image are given with an average dynamic range of 800, a spatial resolution of 10 {mu}m and diameter accuracy about 1% for 50% and 3% for 90% of encircled energy. The high energy focal spot diameters are in agreement with low and very low energy diameters. The phase plate and 14 GHz effects are similar to what we had expected. For a laser shot completed with a continuous phase plate at 14 GHz, and for an energy level of 1.5 kJ per beam at 351 nm, the focal beam diameter at 3% of the peak level is (875 {+-} 45) {mu}m.

  4. Does alprostadil cream hit the spot?

    Science.gov (United States)

    2015-02-01

    Alprostadil, a prostaglandin, has been marketed for many years as a urethral stick and an intracavernous injection for the treatment of erectile dysfunction.(1) It is now available in the form of a cream (Vitaros-Takeda). Adverts for the product declare: "Sex with no pills, pellets or needles. Spot on." In this article, we consider the evidence for alprostadil cream, and its place in the management of erectile dysfunction.

  5. Proteomic analysis of differentially expressed proteins in Fenneropenaeus chinensis hemocytes upon white spot syndrome virus infection.

    Directory of Open Access Journals (Sweden)

    Wei Li

    Full Text Available To elucidate molecular responses of shrimp hemocytes to white spot syndrome virus (WSSV infection, two-dimensional gel electrophoresis was applied to investigate differentially expressed proteins in hemocytes of Chinese shrimp (Fenneropenaeus chinensis at 24 h post infection (hpi. Approximately 580 protein spots were detected in hemocytes of healthy and WSSV-infected shrimps. Quantitative intensity analysis revealed 26 protein spots were significantly up-regulated, and 19 spots were significantly down-regulated. By mass spectrometry, small ubiquitin-like modifier (SUMO 1, cytosolic MnSOD, triosephosphate isomerase, tubulin alpha-1 chain, microtubule-actin cross-linking factor 1, nuclear receptor E75 protein, vacuolar ATP synthase subunit B L form, inositol 1,4,5-trisphosphate receptor, arginine kinase, etc., amounting to 33 differentially modulated proteins were identified successfully. According to Gene Ontology annotation, the identified proteins were classified into nine categories, consisting of immune related proteins, stimulus response proteins, proteins involved in glucose metabolic process, cytoskeleton proteins, DNA or protein binding proteins, proteins involved in steroid hormone mediated signal pathway, ATP synthases, proteins involved in transmembrane transport and ungrouped proteins. Meanwhile, the expression profiles of three up-regulated proteins (SUMO, heat shock protein 70, and arginine kinase and one down-regulated protein (prophenoloxidase were further analyzed by real-time RT-PCR at the transcription level after WSSV infection. The results showed that SUMO and heat shock protein 70 were significantly up-regulated at each sampling time point, while arginine kinase was significantly up-regulated at 12 and 24 hpi. In contrast, prophenoloxidase was significantly down-regulated at each sampling time point. The results of this work provided preliminary data on proteins in shrimp hemocytes involved in WSSV infection.

  6. Replication and expression of the tospoviral genome.

    OpenAIRE

    Poelwijk, van, F.; Haan; Kikkert, M.; Prins, M.; Kormelink, R.; Storms, M.; Lent, van, J.W.M.; Peters, D.; Goldbach, R.

    1996-01-01

    Sequence analysis of the complete, tripartite RNA genomes of two tospoviruses, tomato spotted wilt virus (TSWV) and impatients necrotic spot virus (INSV), demonstrated that they possess five genes that specify six functional proteins. The negative-stranded L RNA encodes the putative polymerase (TSWV 331.5 kDa; INSV 330.3 kDa), the ambisense M RNA encodes a common precursor to the two glycoproteins (G1 and G2) and a nonstructural protein (NSm), and the likewise ambisense S RNA encodes the nucl...

  7. A transcription and translation-coupled DNA replication system using rolling-circle replication.

    Science.gov (United States)

    Sakatani, Yoshihiro; Ichihashi, Norikazu; Kazuta, Yasuaki; Yomo, Tetsuya

    2015-05-27

    All living organisms have a genome replication system in which genomic DNA is replicated by a DNA polymerase translated from mRNA transcribed from the genome. The artificial reconstitution of this genome replication system is a great challenge in in vitro synthetic biology. In this study, we attempted to construct a transcription- and translation-coupled DNA replication (TTcDR) system using circular genomic DNA encoding phi29 DNA polymerase and a reconstituted transcription and translation system. In this system, phi29 DNA polymerase was translated from the genome and replicated the genome in a rolling-circle manner. When using a traditional translation system composition, almost no DNA replication was observed, because the tRNA and nucleoside triphosphates included in the translation system significantly inhibited DNA replication. To minimize these inhibitory effects, we optimized the composition of the TTcDR system and improved replication by approximately 100-fold. Using our system, genomic DNA was replicated up to 10 times in 12 hours at 30 °C. This system provides a step toward the in vitro construction of an artificial genome replication system, which is a prerequisite for the construction of an artificial cell.

  8. Using autonomous replication to physically and genetically define human origins of replication

    Energy Technology Data Exchange (ETDEWEB)

    Krysan, P.J.

    1993-01-01

    The author previously developed a system for studying autonomous replication in human cells involving the use of sequences from the Epstein-Barr virus (EBV) genome to provide extrachromosomal plasmids with a nuclear retention function. Using this system, it was demonstrated that large fragments of human genomic DNA could be isolated which replicate autonomously in human cells. In this study the DNA sequences which function as origins of replication in human cells are defined physically and genetically. These experiments demonstrated that replication initiates at multiple locations distributed throughout the plasmid. Another line of experiments addressed the DNA sequence requirements for autonomous replication in human cells. These experiments demonstrated that human DNA fragments have a higher replication activity than bacterial fragments do. It was also found, however, that the bacterial DNA sequence could support efficient replication if enough copies of it were present on the plasmid. These findings suggested that autonomous replication in human cells does not depend on extensive, specific DNA sequences. The autonomous replication system which the author has employed for these experiments utilizes a cis-acting sequence from the EBV origin and the trans-acting EBNA-1 protein to provide plasmids with a nuclear retention function. It was therefore relevant to verify that the autonomous replication of human DNA fragments did not depend on the replication activity associated with the EBV sequences utilized for nuclear retention. To accomplish this goal, the author demonstrated that plasmids carrying the EBV sequences and large fragments of human DNA could support long-term autonomous replication in hamster cells, which are not permissive for EBV replication.

  9. Mechanism of chromosomal DNA replication initiation and replication fork stabilization in eukaryotes.

    Science.gov (United States)

    Wu, LiHong; Liu, Yang; Kong, DaoChun

    2014-05-01

    Chromosomal DNA replication is one of the central biological events occurring inside cells. Due to its large size, the replication of genomic DNA in eukaryotes initiates at hundreds to tens of thousands of sites called DNA origins so that the replication could be completed in a limited time. Further, eukaryotic DNA replication is sophisticatedly regulated, and this regulation guarantees that each origin fires once per S phase and each segment of DNA gets duplication also once per cell cycle. The first step of replication initiation is the assembly of pre-replication complex (pre-RC). Since 1973, four proteins, Cdc6/Cdc18, MCM, ORC and Cdt1, have been extensively studied and proved to be pre-RC components. Recently, a novel pre-RC component called Sap1/Girdin was identified. Sap1/Girdin is required for loading Cdc18/Cdc6 to origins for pre-RC assembly in the fission yeast and human cells, respectively. At the transition of G1 to S phase, pre-RC is activated by the two kinases, cyclindependent kinase (CDK) and Dbf4-dependent kinase (DDK), and subsequently, RPA, primase-polα, PCNA, topoisomerase, Cdc45, polδ, and polɛ are recruited to DNA origins for creating two bi-directional replication forks and initiating DNA replication. As replication forks move along chromatin DNA, they frequently stall due to the presence of a great number of replication barriers on chromatin DNA, such as secondary DNA structures, protein/DNA complexes, DNA lesions, gene transcription. Stalled forks must require checkpoint regulation for their stabilization. Otherwise, stalled forks will collapse, which results in incomplete DNA replication and genomic instability. This short review gives a concise introduction regarding the current understanding of replication initiation and replication fork stabilization.

  10. Replicating chromatin: a tale of histones

    DEFF Research Database (Denmark)

    Groth, Anja

    2009-01-01

    Chromatin serves structural and functional roles crucial for genome stability and correct gene expression. This organization must be reproduced on daughter strands during replication to maintain proper overlay of epigenetic fabric onto genetic sequence. Nucleosomes constitute the structural...

  11. Control of chromosome replication in caulobacter crescentus.

    Science.gov (United States)

    Marczynski, Gregory T; Shapiro, Lucy

    2002-01-01

    Caulobacter crescentus permits detailed analysis of chromosome replication control during a developmental cell cycle. Its chromosome replication origin (Cori) may be prototypical of the large and diverse class of alpha-proteobacteria. Cori has features that both affiliate and distinguish it from the Escherichia coli chromosome replication origin. For example, requirements for DnaA protein and RNA transcription affiliate both origins. However, Cori is distinguished by several features, and especially by five binding sites for the CtrA response regulator protein. To selectively repress and limit chromosome replication, CtrA receives both protein degradation and protein phosphorylation signals. The signal mediators, proteases, response regulators, and kinases, as well as Cori DNA and the replisome, all show distinct patterns of temporal and spatial organization during cell cycle progression. Future studies should integrate our knowledge of biochemical activities at Cori with our emerging understanding of cytological dynamics in C. crescentus and other bacteria.

  12. LHCb Data Replication During SC3

    CERN Multimedia

    Smith, A

    2006-01-01

    LHCb's participation in LCG's Service Challenge 3 involves testing the bulk data transfer infrastructure developed to allow high bandwidth distribution of data across the grid in accordance with the computing model. To enable reliable bulk replication of data, LHCb's DIRAC system has been integrated with gLite's File Transfer Service middleware component to make use of dedicated network links between LHCb computing centres. DIRAC's Data Management tools previously allowed the replication, registration and deletion of files on the grid. For SC3 supplementary functionality has been added to allow bulk replication of data (using FTS) and efficient mass registration to the LFC replica catalog.Provisional performance results have shown that the system developed can meet the expected data replication rate required by the computing model in 2007. This paper details the experience and results of integration and utilisation of DIRAC with the SC3 transfer machinery.

  13. Initiation of Replication in Escherichia coli

    DEFF Research Database (Denmark)

    Frimodt-Møller, Jakob

    The circular chromosome of Escherichia coli is replicated by two replisomes assembled at the unique origin and moving in the opposite direction until they meet in the less well defined terminus. The key protein in initiation of replication, DnaA, facilitates the unwinding of double-stranded DNA...... to single-stranded DNA in oriC. Although DnaA is able to bind both ADP and ATP, DnaA is only active in initiation when bound to ATP. Although initiation of replication, and the regulation of this, is thoroughly investigated it is still not fully understood. The overall aim of the thesis was to investigate...... the regulation of initiation, the effect on the cell when regulation fails, and if regulation was interlinked to chromosomal organization. This thesis uncovers that there exists a subtle balance between chromosome replication and reactive oxygen species (ROS) inflicted DNA damage. Thus, failure in regulation...

  14. Surface Micro Topography Replication in Injection Moulding

    DEFF Research Database (Denmark)

    Arlø, Uffe Rolf; Hansen, Hans Nørgaard; Kjær, Erik Michael

    2005-01-01

    carried out with rough EDM (electrical discharge machining) mould surfaces, a PS grade, and by applying established three-dimensional topography parameters. Significant quantitative relationships between process parameters and topography parameters were established. It further appeared that replication...

  15. Friction Stir Spot Welding of Advanced High Strength Steels

    Energy Technology Data Exchange (ETDEWEB)

    Hovanski, Yuri; Grant, Glenn J.; Santella, M. L.

    2009-11-13

    Friction stir spot welding techniques were developed to successfully join several advanced high strength steels. Two distinct tool materials were evaluated to determine the effect of tool materials on the process parameters and joint properties. Welds were characterized primarily via lap shear, microhardness, and optical microscopy. Friction stir spot welds were compared to the resistance spot welds in similar strength alloys by using the AWS standard for resistance spot welding high strength steels. As further comparison, a primitive cost comparison between the two joining processes was developed, which included an evaluation of the future cost prospects of friction stir spot welding in advanced high strength steels.

  16. The star chart to Ta bladder cancer: an unsophisticated analysis of two-dimensional gel electrophoresis proteome maps.

    Science.gov (United States)

    Røtterud, Ranveig; Malmström, Per-Uno; Wahlqvist, Rolf; Taskén, Kristin A

    2010-03-01

    To explore the use of two-dimensional gel electrophoresis (2DE) for analysing the proteome of clinically relevant tissue samples such as biopsies from transurethral resections of the bladder (TURB), by generating a Ta proteome map, possibly identifying technical or biological artefacts, and searching for biological subgroups associated with clinical data. Biopsies from 23 patients were homogenized and the protein content was separated by 2DE. The gels were silver stained and scanned, and the resulting pictures were analysed for similarities in the spot pattern. A majority of 18 patients displayed a consistent protein expression profile and a Ta proteome map was constructed by averaging the grey value of each pixel in all 18 pictures. Spot detection was performed on a project proteome map (based on all 23 samples) and resulted in 1583 detected spots. 416 of these which were positively detected in all 18 "Ta-map" samples. Three patients displayed a pattern with some marked alterations to the majority profile, possibly artefacts of yet unknown heredity. One patient revealed a protein pattern deemed to constitute a separate group, later revealed as a blinded control from a T4 tumour. Only one sample was sparse in protein spots, probably containing mostly blood owing to inadequate sampling. No biological subgroups associated with clinical data were identified. A Ta proteome map was successfully created from TURB samples. Deviating protein expression profiles were identified, indicating a future potential to reveal biologically relevant subgroups in this or other stages of urothelial cell carcinomas.

  17. Commercial Building Partnerships Replication and Diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Antonopoulos, Chrissi A.; Dillon, Heather E.; Baechler, Michael C.

    2013-09-16

    This study presents findings from survey and interview data investigating replication efforts of Commercial Building Partnership (CBP) partners that worked directly with the Pacific Northwest National Laboratory (PNNL). PNNL partnered directly with 12 organizations on new and retrofit construction projects, which represented approximately 28 percent of the entire U.S. Department of Energy (DOE) CBP program. Through a feedback survey mechanism, along with personal interviews, PNNL gathered quantitative and qualitative data relating to replication efforts by each organization. These data were analyzed to provide insight into two primary research areas: 1) CBP partners’ replication efforts of technologies and approaches used in the CBP project to the rest of the organization’s building portfolio (including replication verification), and, 2) the market potential for technology diffusion into the total U.S. commercial building stock, as a direct result of the CBP program. The first area of this research focused specifically on replication efforts underway or planned by each CBP program participant. Factors that impact replication include motivation, organizational structure and objectives firms have for implementation of energy efficient technologies. Comparing these factors between different CBP partners revealed patterns in motivation for constructing energy efficient buildings, along with better insight into market trends for green building practices. The second area of this research develops a diffusion of innovations model to analyze potential broad market impacts of the CBP program on the commercial building industry in the United States.

  18. Mycobacterium tuberculosis replicates within necrotic human macrophages

    Science.gov (United States)

    Lerner, Thomas R.; Repnik, Urska; Herbst, Susanne; Collinson, Lucy M.; Griffiths, Gareth

    2017-01-01

    Mycobacterium tuberculosis modulation of macrophage cell death is a well-documented phenomenon, but its role during bacterial replication is less characterized. In this study, we investigate the impact of plasma membrane (PM) integrity on bacterial replication in different functional populations of human primary macrophages. We discovered that IFN-γ enhanced bacterial replication in macrophage colony-stimulating factor–differentiated macrophages more than in granulocyte–macrophage colony-stimulating factor–differentiated macrophages. We show that permissiveness in the different populations of macrophages to bacterial growth is the result of a differential ability to preserve PM integrity. By combining live-cell imaging, correlative light electron microscopy, and single-cell analysis, we found that after infection, a population of macrophages became necrotic, providing a niche for M. tuberculosis replication before escaping into the extracellular milieu. Thus, in addition to bacterial dissemination, necrotic cells provide first a niche for bacterial replication. Our results are relevant to understanding the environment of M. tuberculosis replication in the host. PMID:28242744

  19. The C-terminal Domain (CTD) of Human DNA Glycosylase NEIL1 Is Required for Forming BERosome Repair Complex with DNA Replication Proteins at the Replicating Genome: DOMINANT NEGATIVE FUNCTION OF THE CTD.

    Science.gov (United States)

    Hegde, Pavana M; Dutta, Arijit; Sengupta, Shiladitya; Mitra, Joy; Adhikari, Sanjay; Tomkinson, Alan E; Li, Guo-Min; Boldogh, Istvan; Hazra, Tapas K; Mitra, Sankar; Hegde, Muralidhar L

    2015-08-21

    The human DNA glycosylase NEIL1 was recently demonstrated to initiate prereplicative base excision repair (BER) of oxidized bases in the replicating genome, thus preventing mutagenic replication. A significant fraction of NEIL1 in cells is present in large cellular complexes containing DNA replication and other repair proteins, as shown by gel filtration. However, how the interaction of NEIL1 affects its recruitment to the replication site for prereplicative repair was not investigated. Here, we show that NEIL1 binarily interacts with the proliferating cell nuclear antigen clamp loader replication factor C, DNA polymerase δ, and DNA ligase I in the absence of DNA via its non-conserved C-terminal domain (CTD); replication factor C interaction results in ∼8-fold stimulation of NEIL1 activity. Disruption of NEIL1 interactions within the BERosome complex, as observed for a NEIL1 deletion mutant (N311) lacking the CTD, not only inhibits complete BER in vitro but also prevents its chromatin association and reduced recruitment at replication foci in S phase cells. This suggests that the interaction of NEIL1 with replication and other BER proteins is required for efficient repair of the replicating genome. Consistently, the CTD polypeptide acts as a dominant negative inhibitor during in vitro repair, and its ectopic expression sensitizes human cells to reactive oxygen species. We conclude that multiple interactions among BER proteins lead to large complexes, which are critical for efficient BER in mammalian cells, and the CTD interaction could be targeted for enhancing drug/radiation sensitivity of tumor cells.

  20. Organization of Replication of Ribosomal DNA in Saccharomyces cerevisiae

    NARCIS (Netherlands)

    Linskens, Maarten H.K.; Huberman, Joel A.

    1988-01-01

    Using recently developed replicon mapping techniques, we have analyzed the replication of the ribosomal DNA in Saccharomyces cerevisiae. The results show that (i) the functional origin of replication colocalizes with an autonomously replicating sequence element previously mapped to the

  1. Dynamics of Escherichia coli Chromosome Segregation during Multifork Replication

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck; Youngren, Brenda; Hansen, Flemming G.

    2007-01-01

    Slowly growing Escherichia coli cells have a simple cell cycle, with replication and progressive segregation of the chromosome completed before cell division. In rapidly growing cells, initiation of replication occurs before the previous replication rounds are complete. At cell division...

  2. PEMANFAATAN LIMBAH SEKAM PADI MENJADI SILIKA GEL

    Directory of Open Access Journals (Sweden)

    Prima Astuti Handayani

    2014-12-01

    Full Text Available Sekam padi merupakan salah satu sumber penghasil silika terbesar, berpotensi sebagai bahan pembuatan silika gel. Abu sekam padi mengandung silika sebanyak 87%-97% berat kering. Sintesis silika gel dari abu sekam padi dilakukan dengan mereaksikan abu sekam padi menggunakan larutan NaOH 1N pada suhu 800C selama 1 jam dan dilanjutkan dengan penambahan larutan asam hingga pH=7. Gel yang dihasilkan selanjutnya didiamkan selama 18 jam kemudian dikeringkan pada suhu dikeringkan menggunakan oven pada suhu 800C hingga beratnya konstan. Hasil percobaan diperoleh bahwa silika gel dengan penambahan CH3COOH menghasilkan yield yang lebih besar dibandingkan penambahan HCl. Berdasarkan analisis FT-IR silika gel yang diperoleh memiliki gugus Si-O-Si dan gugus Si-OH. Silika gel dengan penambahan HCl memiliki surface area sebesar 65,558 m2/g, total pore volume 0,1935 cc/g, dan average pore size sebesar 59,0196 Å. Sedangkan silika gel dengan penambahan CH3COOH memiliki surface area sebesar 9,685 m2/g, total pore volume 0,02118 cc/g, dan average pore size sebesar 43,7357Å. Silika gel dengan penambahanCH3COOH memiliki kemampuan menyerap kelembaban udara yang lebih baik dibanding silika gel dengan penambahan HCl. Rice hull ash (RHA is one of the biggest source of silica, potential for sintesis silica gel. RHA contains silica as many as 87 % -97 %. Synthesis of silica gel from rice hull ash was done by reaction using NaOH solution at temperature 800C for 1 hour and followed by the addition of an acid solution until pH=7. The gel were rested with time aging 18 hour, and then dried using oven at temperature 800C until constant weigh. The results obtained that the silica gel with the addition of CH3COOH produce higher yields than the addition of HCl. Based on FT-IR analysis, silica gel has a group of silanol (Si-`OH and siloxan (Si-O-Si group. Silica gel with the addition of HCl has a surface area 65,558 m2/g, a total pore volume 0,1935 cc/g, and average pore size 59

  3. Time Resolved X-Ray Spot Size Diagnostic

    CERN Document Server

    Richardson, Roger; Falabella, Steven; Guethlein, Gary; Raymond, Brett; Weir, John

    2005-01-01

    A diagnostic was developed for the determination of temporal history of an X-ray spot. A pair of thin (0.5 mm) slits image the x-ray spot to a fast scintillator which is coupled to a fast detector, thus sampling a slice of the X-Ray spot. Two other scintillator/detectors are used to determine the position of the spot and total forward dose. The slit signal is normalized to the dose and the resulting signal is analyzed to get the spot size. The position information is used to compensate for small changes due to spot motion and misalignment. The time resolution of the diagnostic is about 1 ns and measures spots from 0.5 mm to over 3 mm. The theory and equations used to calculate spot size and position are presented, as well as data. The calculations assume a symmetric, Gaussian spot. The spot data is generated by the ETA II accelerator, a 2kA, 5.5 MeV, 60ns electron beam focused on a Tantalum target. The spot generated is typically about 1 mm FWHM. Comparisons are made to an X-ray pinhole camera which images th...

  4. Evidence against a supervoid causing the CMB Cold Spot

    Science.gov (United States)

    Mackenzie, Ruari; Shanks, Tom; Bremer, Malcolm N.; Cai, Yan-Chuan; Gunawardhana, Madusha L. P.; Kovács, András; Norberg, Peder; Szapudi, Istvan

    2017-09-01

    We report the results of the 2dF-VST ATLAS Cold Spot galaxy redshift survey (2CSz) based on imaging from VST ATLAS and spectroscopy from 2dF AAOmega over the core of the CMB Cold Spot. We sparsely surveyed the inner 5° radius of the Cold Spot to a limit of iAB ≤ 19.2, sampling ∼7000 galaxies at z data out to z ∼ 1, we conclude that the CMB Cold Spot could not have been imprinted by a void confined to the inner core of the Cold Spot. Additionally, we find that our 'control' field GAMA G23 shows a similarity in its galaxy redshift distribution to the Cold Spot. Since the GAMA G23 line of sight shows no evidence of a CMB temperature decrement, we conclude that the Cold Spot may have a primordial origin rather than being due to line-of-sight effects.

  5. Metal-silica sol-gel materials

    Science.gov (United States)

    Stiegman, Albert E. (Inventor)

    2002-01-01

    The present invention relates to a single phase metal-silica sol-gel glass formed by the co-condensation of a transition metal with silicon atoms where the metal atoms are uniformly distributed within the sol-gel glass as individual metal centers. Any transition metal may be used in the sol-gel glasses. The present invention also relates to sensor materials where the sensor material is formed using the single phase metal-silica sol-gel glasses. The sensor materials may be in the form of a thin film or may be attached to an optical fiber. The present invention also relates to a method of sensing chemicals using the chemical sensors by monitoring the chromatic change of the metal-silica sol-gel glass when the chemical binds to the sensor. The present invention also relates to oxidation catalysts where a metal-silica sol-gel glass catalyzes the reaction. The present invention also relates to a method of performing oxidation reactions using the metal-silica sol-gel glasses. The present invention also relates to organopolymer metal-silica sol-gel composites where the pores of the metal-silica sol-gel glasses are filled with an organic polymer polymerized by the sol-gel glass.

  6. Sol-gel electrochromic device

    OpenAIRE

    1994-01-01

    All solid state electrochromic devices have potential applications in architectural and automotive fields to regulate the transmission and reflection of radiant energy. We present the optical and electrochemical characteristics of two solid state windows having the configuration glass/ITO/TiO2-CeO2/TiO2/TiO2-CeO2/ITO/glass and glass/ITO/WOa/TiO2/TiO2-CeO2/ITO/glass where the three internal layers have been prepared by sol gel methods. The preparation of the individual sols and some physical p...

  7. Motility initiation in active gels

    CERN Document Server

    Recho, Pierre; Truskinovsky, Lev

    2015-01-01

    Motility initiation in crawling cells requires a symmetry breaking mechanism which transforms a symmetric state into a polarized state. Experiments on keratocytes suggest that polarization is triggered by increased contractility of motor proteins. In this paper we argue that contraction can be responsible not only for the symmetry breaking transition but also for the incipient translocation of the segment of an active gel mimicking the crawling cell. Our model suggests that when the contractility increases sufficiently far beyond the motility initiation threshold, the cell can stop and re-symmetrizes. The proposed theory reproduces the motility initiation pattern in fish keratocytes and the behavior of keratocytes prior to cell division.

  8. Inorganic replication of human hair and in situ synthesis of gold nanoparticles

    Institute of Scientific and Technical Information of China (English)

    LIU Shuxia; HE Junhui

    2007-01-01

    The structure of hair was replicated via a sol-gel process using human hair as a template.When using silicate and tetraethoxysilane(TEOS)as the precursor,the cell structure of the hair cuticle was not well replicated.When using Ti(OnBu)4 as the precursor,however,titania microtubes were obtained,with nanopores in their walls and nanoporous platelets on meir outer surfaces,which were derived from cuticle cells on the hair surfaces.The nanopores in the microtubes acted as an effective nanoreactor for in situ synthesis of Au nanoparticles.The microchannels,nanopores and noble metal nanoparticles may provide a unique combination that would be attractive in applications such as catalysis,adsorption,and separation.

  9. The effect of concanavalin A on the replication of rotavirus (SA-11 in cell culture

    Directory of Open Access Journals (Sweden)

    Hasenack Beatriz S.

    2002-01-01

    Full Text Available Rotavirus (RV strain SA-11 was studied with respect to its infectivity in MA-104 cell cultures and the effect of concanavalin A (ConA. Receptors for ConA at the surface of MA-104 cell were determined by fluorescence assay and specifically inhibited by D-mannose. The kinetics of virus growth was carried out by plaque assay. Electron microscopy and polyacrylamide gel electrophoresis were used for monitoring the experiments. It was concluded that RV replication was not affected consistently by ConA, however it interfered with the development of cytopathic effect (CPE without altering virus yields.

  10. SV40 utilizes ATM kinase activity to prevent non-homologous end joining of broken viral DNA replication products.

    Directory of Open Access Journals (Sweden)

    Gregory A Sowd

    2014-12-01

    Full Text Available Simian virus 40 (SV40 and cellular DNA replication rely on host ATM and ATR DNA damage signaling kinases to facilitate DNA repair and elicit cell cycle arrest following DNA damage. During SV40 DNA replication, ATM kinase activity prevents concatemerization of the viral genome whereas ATR activity prevents accumulation of aberrant genomes resulting from breakage of a moving replication fork as it converges with a stalled fork. However, the repair pathways that ATM and ATR orchestrate to prevent these aberrant SV40 DNA replication products are unclear. Using two-dimensional gel electrophoresis and Southern blotting, we show that ATR kinase activity, but not DNA-PK(cs kinase activity, facilitates some aspects of double strand break (DSB repair when ATM is inhibited during SV40 infection. To clarify which repair factors associate with viral DNA replication centers, we examined the localization of DSB repair proteins in response to SV40 infection. Under normal conditions, viral replication centers exclusively associate with homology-directed repair (HDR and do not colocalize with non-homologous end joining (NHEJ factors. Following ATM inhibition, but not ATR inhibition, activated DNA-PK(cs and KU70/80 accumulate at the viral replication centers while CtIP and BLM, proteins that initiate 5' to 3' end resection during HDR, become undetectable. Similar to what has been observed during cellular DSB repair in S phase, these data suggest that ATM kinase influences DSB repair pathway choice by preventing the recruitment of NHEJ factors to replicating viral DNA. These data may explain how ATM prevents concatemerization of the viral genome and promotes viral propagation. We suggest that inhibitors of DNA damage signaling and DNA repair could be used during infection to disrupt productive viral DNA replication.

  11. SV40 utilizes ATM kinase activity to prevent non-homologous end joining of broken viral DNA replication products.

    Science.gov (United States)

    Sowd, Gregory A; Mody, Dviti; Eggold, Joshua; Cortez, David; Friedman, Katherine L; Fanning, Ellen

    2014-12-01

    Simian virus 40 (SV40) and cellular DNA replication rely on host ATM and ATR DNA damage signaling kinases to facilitate DNA repair and elicit cell cycle arrest following DNA damage. During SV40 DNA replication, ATM kinase activity prevents concatemerization of the viral genome whereas ATR activity prevents accumulation of aberrant genomes resulting from breakage of a moving replication fork as it converges with a stalled fork. However, the repair pathways that ATM and ATR orchestrate to prevent these aberrant SV40 DNA replication products are unclear. Using two-dimensional gel electrophoresis and Southern blotting, we show that ATR kinase activity, but not DNA-PK(cs) kinase activity, facilitates some aspects of double strand break (DSB) repair when ATM is inhibited during SV40 infection. To clarify which repair factors associate with viral DNA replication centers, we examined the localization of DSB repair proteins in response to SV40 infection. Under normal conditions, viral replication centers exclusively associate with homology-directed repair (HDR) and do not colocalize with non-homologous end joining (NHEJ) factors. Following ATM inhibition, but not ATR inhibition, activated DNA-PK(cs) and KU70/80 accumulate at the viral replication centers while CtIP and BLM, proteins that initiate 5' to 3' end resection during HDR, become undetectable. Similar to what has been observed during cellular DSB repair in S phase, these data suggest that ATM kinase influences DSB repair pathway choice by preventing the recruitment of NHEJ factors to replicating viral DNA. These data may explain how ATM prevents concatemerization of the viral genome and promotes viral propagation. We suggest that inhibitors of DNA damage signaling and DNA repair could be used during infection to disrupt productive viral DNA replication.

  12. A novel mechanism of "metal gel-shift" by histidine-rich Ni2+-binding Hpn protein from Helicobacter pylori strain SS1.

    Science.gov (United States)

    Shelake, Rahul Mahadev; Ito, Yuki; Masumoto, Junya; Morita, Eugene Hayato; Hayashi, Hidenori

    2017-01-01

    Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) is a universally used method for determining approximate molecular weight (MW) in protein research. Migration of protein that does not correlate with formula MW, termed "gel shifting" appears to be common for histidine-rich proteins but not yet studied in detail. We investigated "gel shifting" in Ni2+-binding histidine-rich Hpn protein cloned from Helicobacter pylori strain SS1. Our data demonstrate two important factors determining "gel shifting" of Hpn, polyacrylamide-gel concentration and metal binding. Higher polyacrylamide-gel concentrations resulted in faster Hpn migration. Irrespective of polyacrylamide-gel concentration, preserved Hpn-Ni2+ complex migrated faster (3-4 kDa) than apo-Hpn, phenomenon termed "metal gel-shift" demonstrating an intimate link between Ni2+ binding and "gel shifting". To examine this discrepancy, eluted samples from corresponding spots on SDS-gel were analyzed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS). The MW of all samples was the same (6945.66±0.34 Da) and identical to formula MW with or without added mass of Ni2+. MALDI-TOF-MS of Ni2+-treated Hpn revealed that monomer bound up to six Ni2+ ions non-cooperatively, and equilibrium between protein-metal species was reliant on Ni2+ availability. This corroborates with gradually increased heterogeneity of apo-Hpn band followed by compact "metal-gel shift" band on SDS-PAGE. In view of presented data metal-binding and "metal-gel shift" models are discussed.

  13. Resolution by unassisted Top3 points to template switch recombination intermediates during DNA replication.

    Science.gov (United States)

    Glineburg, M Rebecca; Chavez, Alejandro; Agrawal, Vishesh; Brill, Steven J; Johnson, F Brad

    2013-11-15

    The evolutionarily conserved Sgs1/Top3/Rmi1 (STR) complex plays vital roles in DNA replication and repair. One crucial activity of the complex is dissolution of toxic X-shaped recombination intermediates that accumulate during replication of damaged DNA. However, despite several years of study the nature of these X-shaped molecules remains debated. Here we use genetic approaches and two-dimensional gel electrophoresis of genomic DNA to show that Top3, unassisted by Sgs1 and Rmi1, has modest capacities to provide resistance to MMS and to resolve recombination-dependent X-shaped molecules. The X-shaped molecules have structural properties consistent with hemicatenane-related template switch recombination intermediates (Rec-Xs) but not Holliday junction (HJ) intermediates. Consistent with these findings, we demonstrate that purified Top3 can resolve a synthetic Rec-X but not a synthetic double HJ in vitro. We also find that unassisted Top3 does not affect crossing over during double strand break repair, which is known to involve double HJ intermediates, confirming that unassisted Top3 activities are restricted to substrates that are distinct from HJs. These data help illuminate the nature of the X-shaped molecules that accumulate during replication of damaged DNA templates, and also clarify the roles played by Top3 and the STR complex as a whole during the resolution of replication-associated recombination intermediates.

  14. Isolation of restriction fragments containing origins of replication from complex genomes.

    Science.gov (United States)

    Mesner, Larry D; Hamlin, Joyce L

    2015-01-01

    The identification and isolation of origins of replication from mammalian genomes has been a demanding task owing to the great complexity of these genomes. However, two methods have been refined in recent years each of which allows significant enrichment of recently activated origins of replication from asynchronous cell cultures. In one of these, nascent strands are melted from the long template DNA, and the small, origin-centered strands are isolated on sucrose gradients. The second method involves the selective entrapment of bubble-containing fragments in gelling agarose and their subsequent recovery and isolation by molecular cloning. Libraries prepared by this method from Chinese hamster and human cells have been shown to be extremely pure, and provide a renewable resource of origins that can be used as probes on microarrays or sequenced by high-throughput techniques to localize them within the genomic source. The bubble-trapping method is described here for asynchronous mammalian cells that grow with reasonable doubling times and from which nuclear matrices can be reliably prepared. The method for nuclear matrix preparation and enrichment of replication intermediates is described in an accompanying chapter entitled "Purification of restriction fragments containing replication intermediates from mammalian cells for 2-D gel analysis" (Chapter 16 ).

  15. Active Gel Model of Amoeboid Cell Motility

    CERN Document Server

    Callan-Jones, A C

    2013-01-01

    We develop a model of amoeboid cell motility based on active gel theory. Modeling the motile apparatus of a eukaryotic cell as a confined layer of finite length of poroelastic active gel permeated by a solvent, we first show that, due to active stress and gel turnover, an initially static and homogeneous layer can undergo a contractile-type instability to a polarized moving state in which the rear is enriched in gel polymer. This agrees qualitatively with motile cells containing an actomyosin-rich uropod at their rear. We find that the gel layer settles into a steadily moving, inhomogeneous state at long times, sustained by a balance between contractility and filament turnover. In addition, our model predicts an optimal value of the gel-susbstrate adhesion leading to maximum layer speed, in agreement with cell motility assays. The model may be relevant to motility of cells translocating in complex, confining environments that can be mimicked experimentally by cell migration through microchannels.

  16. Self-Pumping Active Gel

    Science.gov (United States)

    Wu, Kun-Ta; Hishamunda, Jean Bernard; Fraden, Seth; Dogic, Zvonimir

    Isotropic active gels are the network which is consist of cross-linked building blocks and the structure of which changes randomly and isotropically with time. Dogic et. al. show that pairs of anti-parallel microtubules form extensile bundles, which merge, extend, and buckle. In an unconfined system, the dynamics of these bundles causes spontaneous turbulent-like flow driven by motion of microscopic molecular motors. We found that confining these active gels in a millimeter sized toroids causes a transition into a new dynamical state characterized by circulation currents persisting for hours until ATP is depleted. We show how toroid dimensions impact the properties of self-organized circular currents, how directions of circulation can be designed by engineering ratchet-shaped boundaries, and how circulations of connected toroids can be either synchronized or antisynchronized. Furthermore, we demonstrate that the flow rate in the circulation is independent of curvature and length of flow path. The flow rate persists for centimeters without decay, disregarding conventional pipe flow resistance. Such findings pave the path to self-pumping pipe transport and performing physical work with biological system.

  17. Gel trapping of dense colloids.

    Science.gov (United States)

    Laxton, Peter B; Berg, John C

    2005-05-01

    Phase density differences in sols, foams, or emulsions often lead to sedimentation or creaming, causing problems for materials where spatial uniformity over extended periods of time is essential. The problem may be addressed through the use of rheology modifiers in the continuous phase. Weak polymer gels have found use for this purpose in the food industry where they appear to be capable of trapping dispersoid particles in a three-dimensional matrix while displaying water-like viscosities at low shear. Attempts to predict sedimentation stability in terms of particle properties (size, shape, density difference) and gel yield stress have led to qualitative success for suspensions of large particles. The effect of particle size, however, in particular the case in which colloidal dimensions are approached, has not been investigated. The present work seeks to determine useful stability criteria for colloidal dispersions in terms of readily accessible viscoelastic descriptors. Results are reported for systems consisting of 12 microm poly(methyl methacrylate) (PMMA) spheres dispersed in aqueous gellan gum. Monovalent salt concentration is varied to control rheological properties, and sedimentation/centrifugation experiments are performed to determine dispersion stability. Necessary conditions for stability consist of a minimum yield stress together with a value of tan delta less than unity.

  18. A Novel Strategy for Characterization of Glycosylated Proteins Separated by Gel Electrophoresis

    DEFF Research Database (Denmark)

    Larsen, Martin; Skottrup, Peter; Enghild, Jan J.;

    2005-01-01

    Protein glycosylation can be vital for changing the function or physiochemical properties of a protein. Abnormal glycosylation can lead to protein malfunction, resulting in severe diseases. Therefore, it is important to develop techniques for characterization of such modifications in proteins...... at a sensitivity level comparable with state-of-the-art proteomics. Whereas techniques exist for characterization of high abundant glycoproteins, no single method is presently capable of providing information on both site occupancy and glycan structure on a single band or spot excised from an electrophoretic gel....... We present a new technique, which allows full characterization of low amounts of glycoproteins separated by gel electrophoresis. The method takes advantage of sequential specific and non-specific enzymatic treatment, followed by selective purification and characterization of the glycopeptides using...

  19. Synthesis of Hydroxypropyl-β-cyclodextrin Bonded Silica-gel and its Application to Resolution

    Institute of Scientific and Technical Information of China (English)

    Jin Gang YU; Ke Long HUANG; Du Shu HUANG; Jin Yue PU

    2006-01-01

    In order to set up a simple and effective method for resolution of optical isomers,hydroxypropyl-β-cyclodextrin was bonded to silica-gel, which can be used for preparation of thin-layer chromatography plates. Resolution of clenbuterol and propranolol were investigated on these thin-layer chromatography plates using different combinations of solvent systems at ambient temperature. The best simultaneous resolution was achieved in solvent system of acetonitrilen-butanol (50:50, v/v). Rst values of resolution of clenbuterol hydrochloride and propranolol hydrochloride are 3.6 and 4.3, respectively. The spots of different enantiomers are separated clearly. The results showed that hydroxypropyl-β-cyclodextrin bonded silica-gel could be successful in resolution of chiral adrenergic drugs. The study offers a direct, rapid and reliable method for separation of this kind of optically active compounds.

  20. Characteristics of polyacrylamide gel with THPC and Turnbull Blue gel dosimeters evaluated using optical tomography

    Science.gov (United States)

    Pilařová (Vávrů), Kateřina; Kozubíková, Petra; Šolc, Jaroslav; Spěváček, Václav

    2014-11-01

    The purpose of this study was to compare characteristics of radiochromic gel - Turnbull Blue gel (TB gel) with polymer gel - polyacrylamide gel and tetrakis hydroxymethyl phosphonium chloride (PAGAT) using optical tomography. Both types of gels were examined in terms of dose sensitivity, dose response linearity and background value of spectrophotometric absorbance. The calibration curve was obtained for 60Co irradiation performed on Gammacell 220 at predefined gamma dose levels between 0 and 140 Gy for TBG and 0-15 Gy for PAGAT. To measure relative dose distributions from stereotactic irradiation, dosimeters were irradiated on Leksell Gamma Knife Perfexion. The cylindrical glass housings filled with gel were attached to the stereotactic frame. They were exposed with single shot and 16 mm collimator by 65 Gy to a 50% prescription isodose for TB gel and 4 Gy to a 50% prescription isodose for PAGAT. Evaluations of dosimeters were performed on an UV-vis Spectrophotometer Helios β and an optical cone beam homemade tomography scanner with a 16-bit astronomy CCD camera with a set of color filters. The advantages and potential disadvantages for both types of gel dosimeters were summarized. Dose distribution in central slice and measured profiles of 16 mm shot shows excellent correspondence with treatment planning system Leksell GammaPlan® for both PAGAT and Turnbull Blue gels. Gel dosimeters are suitable for steep dose gradient verification. An optical tomography evaluation method is successful. Dose response characteristics of TB gel and PAGAT gel are presented.

  1. Optical CT scanner for in-air readout of gels for external radiation beam 3D dosimetry.

    Science.gov (United States)

    Ramm, Daniel; Rutten, Thomas P; Shepherd, Justin; Bezak, Eva

    2012-06-21

    Optical CT scanners for a 3D readout of externally irradiated radiosensitive hydrogels currently require the use of a refractive index (RI) matching liquid bath to obtain suitable optical ray paths through the gel sample to the detector. The requirement for a RI matching liquid bath has been negated by the design of a plastic cylindrical gel container that provides parallel beam geometry through the gel sample for the majority of the projection. The design method can be used for various hydrogels. Preliminary test results for the prototype laser beam scanner with ferrous xylenol-orange gel show geometric distortion of 0.2 mm maximum, spatial resolution limited to beam spot size of about 0.4 mm and 0.8% noise (1 SD) for a uniform irradiation. Reconstruction of a star pattern irradiated through the cylinder walls demonstrates the suitability for external beam applications. The extremely simple and cost-effective construction of this optical CT scanner, together with the simplicity of scanning gel samples without RI matching fluid increases the feasibility of using 3D gel dosimetry for clinical external beam dose verifications.

  2. Gel time of calcium acrylate grouting material

    Institute of Scientific and Technical Information of China (English)

    韩同春

    2004-01-01

    Calcium acrylate is a polymerized grout, and can polymerize in an aqueous solution. The polymerizationreaction utilizes ammonium persulfate as a catalyst and sodium thiosulfate as the activator. Based on the theory of reactionkinetics, this study on the relation between gel time and concentration of activator and catalyst showed that gel time ofcalcium acrylate is inversely proportional to activator and catalyst concentration. A formula of gel time is proposed, and anexample is provided to verify the proposed formula.

  3. Gel time of calcium acrylate grouting material

    Institute of Scientific and Technical Information of China (English)

    韩同春

    2004-01-01

    Calcium acrylate is a polymerized grout, and can polymerize in an aqueous solution. The polymerization reaction utilizes ammonium persulfate as a catalyst and sodium thiosulfate as the activator. Based on the theory of reaction kinetics, this study on the relation between gel time and concentration of activator and catalyst showed that gel time of calcium acrylate is inversely proportional to activator and catalyst concentration. A formula of gel time is proposed, and an example is provided to verify the proposed formula.

  4. Stabilized aqueous gels and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, B.L.

    1978-08-29

    New improved aqueous gels, and methods of using same in contacting subterranean formations, are provided. The gels are prepared by gelling an aqueous brine having incorporated therein a water-soluble cellulose ether such as a carboxymethylcellulose (CMC), and are rendered more stable to decomposition by incorporating a sulfoalkylated tannin stabilizing agent, such as a sulfomethylated quebracho (SMQ), in the gel during the preparation thereof.

  5. Dynamics of Escherichia coli chromosome segregation during multifork replication.

    Science.gov (United States)

    Nielsen, Henrik J; Youngren, Brenda; Hansen, Flemming G; Austin, Stuart

    2007-12-01

    Slowly growing Escherichia coli cells have a simple cell cycle, with replication and progressive segregation of the chromosome completed before cell division. In rapidly growing cells, initiation of replication occurs before the previous replication rounds are complete. At cell division, the chromosomes contain multiple replication forks and must be segregated while this complex pattern of replication is still ongoing. Here, we show that replication and segregation continue in step, starting at the origin and progressing to the replication terminus. Thus, early-replicated markers on the multiple-branched chromosomes continue to separate soon after replication to form separate protonucleoids, even though they are not segregated into different daughter cells until later generations. The segregation pattern follows the pattern of chromosome replication and does not follow the cell division cycle. No extensive cohesion of sister DNA regions was seen at any growth rate. We conclude that segregation is driven by the progression of the replication forks.

  6. Optical tweezers reveal how proteins alter replication

    Science.gov (United States)

    Chaurasiya, Kathy

    Single molecule force spectroscopy is a powerful method that explores the DNA interaction properties of proteins involved in a wide range of fundamental biological processes such as DNA replication, transcription, and repair. We use optical tweezers to capture and stretch a single DNA molecule in the presence of proteins that bind DNA and alter its mechanical properties. We quantitatively characterize the DNA binding mechanisms of proteins in order to provide a detailed understanding of their function. In this work, we focus on proteins involved in replication of Escherichia coli (E. coli ), endogenous eukaryotic retrotransposons Ty3 and LINE-1, and human immunodeficiency virus (HIV). DNA polymerases replicate the entire genome of the cell, and bind both double-stranded DNA (dsDNA) and single-stranded DNA (ssDNA) during DNA replication. The replicative DNA polymerase in the widely-studied model system E. coli is the DNA polymerase III subunit alpha (DNA pol III alpha). We use optical tweezers to determine that UmuD, a protein that regulates bacterial mutagenesis through its interactions with DNA polymerases, specifically disrupts alpha binding to ssDNA. This suggests that UmuD removes alpha from its ssDNA template to allow DNA repair proteins access to the damaged DNA, and to facilitate exchange of the replicative polymerase for an error-prone translesion synthesis (TLS) polymerase that inserts nucleotides opposite the lesions, so that bacterial DNA replication may proceed. This work demonstrates a biophysical mechanism by which E. coli cells tolerate DNA damage. Retroviruses and retrotransposons reproduce by copying their RNA genome into the nuclear DNA of their eukaryotic hosts. Retroelements encode proteins called nucleic acid chaperones, which rearrange nucleic acid secondary structure and are therefore required for successful replication. The chaperone activity of these proteins requires strong binding affinity for both single- and double-stranded nucleic

  7. Pulmonary effects of spot welding in automobile assembly.

    Science.gov (United States)

    Loukzadeh, Zeeba; Sharifian, Seyed Akbar; Aminian, Omid; Shojaoddiny-Ardekani, Ahmad

    2009-06-01

    Spot welding is a type of resistance welding in which pieces of metals are pressed together and an electric current is passed through them. Spot welders are at risk of contact with some potentially hazardous agents but there are few studies about the respiratory effects of spot welding. Our objective was to study lung function and respiratory symptoms among spot welders and office workers at an automobile assembly factory in Iran. This was a cross-sectional study of 137 male spot welders and 129 office workers. We used a questionnaire to record demographic data, smoking habits, work history and respiratory symptoms. Spirometry was performed to assess lung function status. Metal fume samples from the respiratory zone of spot welders were analysed. The concentrations of metal fume were less than the American Conference of Industrial Hygienists (ACGIH) threshold limit values. There were significantly lower values for average forced expiratory volume in 1st second (FEV(1)), FEV(1)/forced vital capacity and 25-75% forced expiratory flow in spot welders compared to controls. There was also a significantly raised prevalence of respiratory symptoms (sputum and dyspnoea) in spot welders. Fifteen per cent of spot welders and 1% of controls had an obstructive pattern in spirometry. Our survey suggests that spot welders are at risk of developing respiratory symptoms and decreasing pulmonary function values despite their exposure to components of welding fume being within ACGIH guidelines.

  8. The fractal nature of vacuum arc cathode spots

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Andre

    2005-05-27

    Cathode spot phenomena show many features of fractals, for example self-similar patterns in the emitted light and arc erosion traces. Although there have been hints on the fractal nature of cathode spots in the literature, the fractal approach to spot interpretation is underutilized. In this work, a brief review of spot properties is given, touching the differences between spot type 1 (on cathodes surfaces with dielectric layers) and spot type 2 (on metallic, clean surfaces) as well as the known spot fragment or cell structure. The basic properties of self-similarity, power laws, random colored noise, and fractals are introduced. Several points of evidence for the fractal nature of spots are provided. Specifically power laws are identified as signature of fractal properties, such as spectral power of noisy arc parameters (ion current, arc voltage, etc) obtained by fast Fourier transform. It is shown that fractal properties can be observed down to the cutoff by measurement resolution or occurrence of elementary steps in physical processes. Random walk models of cathode spot motion are well established: they go asymptotically to Brownian motion for infinitesimal step width. The power spectrum of the arc voltage noise falls as 1/f {sup 2}, where f is frequency, supporting a fractal spot model associated with Brownian motion.

  9. Initial experiments with gel-water: towards MRI-linac dosimetry and imaging.

    Science.gov (United States)

    Alnaghy, Sarah J; Gargett, Maegan; Liney, Gary; Petasecca, Marco; Begg, Jarrad; Espinoza, Anthony; Newall, Matthew K; Duncan, Mitchell; Holloway, Lois; Lerch, Michael L F; Lazea, Mircea; Rosenfeld, Anatoly B; Metcalfe, Peter

    2016-12-01

    Tracking the position of a moving radiation detector in time and space during data acquisition can replicate 4D image-guided radiotherapy (4DIGRT). Magnetic resonance imaging (MRI)-linacs need MRI-visible detectors to achieve this, however, imaging solid phantoms is an issue. Hence, gel-water, a material that provides signal for MRI-visibility, and which will in future work, replace solid water for an MRI-linac 4DIGRT quality assurance tool, is discussed. MR and CT images of gel-water were acquired for visualisation and electron density verification. Characterisation of gel-water at 0 T was compared to Gammex-RMI solid water, using MagicPlate-512 (M512) and RMI Attix chamber; this included percentage depth dose, tissue-phantom ratio (TPR20/10), tissue-maximum ratio (TMR), profiles, output factors, and a gamma analysis to investigate field penumbral differences. MR images of a non-powered detector in gel-water demonstrated detector visualisation. The CT-determined gel-water electron density agreed with the calculated value of 1.01. Gel-water depth dose data demonstrated a maximum deviation of 0.7% from solid water for M512 and 2.4% for the Attix chamber, and by 2.1% for TPR20/10 and 1.0% for TMR. FWHM and output factor differences between materials were ≤0.3 and ≤1.4%. M512 data passed gamma analysis with 100% within 2%, 2 mm tolerance for multileaf collimator defined fields. Gel-water was shown to be tissue-equivalent for dosimetry and a feasible option to replace solid water.

  10. Buckling Instability in Liquid Crystalline Physical Gels

    OpenAIRE

    Verduzco, Rafael; Meng, Guangnan; Kornfield, Julia A; Meyer, Robert B.

    2006-01-01

    In a nematic gel we observe a low-energy buckling deformation arising from soft and semisoft elastic modes. We prepare the self-assembled gel by dissolving a coil–side-group liquid-crystalline polymer–coil copolymer in a nematic liquid crystal. The gel has long network strands and a precisely tailored structure, making it ideal for studying nematic rubber elasticity. Under polarized optical microscopy we observe a striped texture that forms when gels uniformly aligned at 35 °C are cooled to r...

  11. Conducting polymer electrodes for gel electrophoresis.

    Science.gov (United States)

    Bengtsson, Katarina; Nilsson, Sara; Robinson, Nathaniel D

    2014-01-01

    In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that π-conjugated polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis) systems. In this report, we extend our previous result to gel electrophoresis, and show that electrodes containing PEDOT can be used with a commercial polyacrylamide gel electrophoresis system with minimal impact to the resulting gel image or the ionic transport measured during a separation.

  12. Food gels: gelling process and new applications.

    Science.gov (United States)

    Banerjee, Soumya; Bhattacharya, Suvendu

    2012-01-01

    Food gels are viscoelastic substances and several gelled products are manufactured throughout the world. The gelling agents in foods are usually polysaccharides and proteins. In food gels, the polymer molecules are not cross-linked by covalent bonds with the exception of disulphide bonds in some protein gels. Instead, the molecules are held together by a combination of weak inter-molecular forces like hydrogen bonds, electrostatic forces, Van der Waals forces, and hydrophobic interactions. Polysaccharides including hydrocolloids are strongly hydrated in aqueous medium but they tend to have less ordered structures. The mechanism of gelation depends on the nature of the gelling agent(s) and on the conditions of gel formation like the temperature, the presence of ions, the pH, and the concentration of gelling agents, etc. Characterization of gels can be performed in several ways of which rheological measurements are frequently practiced. Multi-component or mixed gel system is an important area of interest in which two or more gelling components are simultaneously used to achieve certain specific structural and functional characteristics. We here discuss about the different gels and gelling agents, the characterization of gels, and the mechanism of gelation with an emphasis on mixed or multi-component gels that would have significant commercial applications.

  13. Conducting polymer electrodes for gel electrophoresis.

    Directory of Open Access Journals (Sweden)

    Katarina Bengtsson

    Full Text Available In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that π-conjugated polymers such as poly(3,4-ethylenedioxythiophene (PEDOT can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis systems. In this report, we extend our previous result to gel electrophoresis, and show that electrodes containing PEDOT can be used with a commercial polyacrylamide gel electrophoresis system with minimal impact to the resulting gel image or the ionic transport measured during a separation.

  14. Count response model for the CMB spots

    CERN Document Server

    Giovannini, Massimo

    2010-01-01

    The statistics of the curvature quanta generated during a stage of inflationary expansion is used to derive a count response model for the large-scale phonons determining, in the concordance lore, the warmer and the cooler spots of the large-scale temperature inhomogeneities. The multiplicity distributions for the counting statistics are shown to be generically overdispersed in comparison with conventional Poissonian regressions. The generalized count response model deduced hereunder accommodates an excess of correlations in the regime of high multiplicities and prompts dedicated analyses with forthcoming data collected by instruments of high angular resolution and high sensitivity to temperature variations per pixel.

  15. Real prices from spot foreign exchange market

    Science.gov (United States)

    Petroni, Filippo; Serva, Maurizio

    2004-12-01

    In this work we discuss the problem of price definition when using high frequency foreign exchange data. If one uses the spot mid price a strong autocorrelation of returns, at one lag, is found which is only due to microstructure effect and does not capture the real behavior of price dynamics. This autocorrelation increases the intraday volatility estimated from this type of data. To solve this problem we introduce an algorithm which is able, by using the no-arbitrage principle, of eliminating every microstructure effects.

  16. Algorithms For Detection Of Correlation Spots

    Science.gov (United States)

    Scholl, Marija S.; Udomkesmalee, Suraphol

    1993-01-01

    Three algorithms provide for improved postprocessing of outputs of optical correlators based on binary phase-only filters. Detect correlation spots. Function in presence of noise and executed rapidly. First algorithm starts processing correlation-image data while data fed out of video camera and digitized for subsequent analysis. Second involves convolution of correlation image with small-window two-dimensional impulse-response function followed by threshold operation in which negative values of convolution integral set to zero. Third affects generation as well as postprocessing of correlation image.

  17. Advanced spot quality analysis in two-colour microarray experiments

    Directory of Open Access Journals (Sweden)

    Vetter Guillaume

    2008-09-01

    Full Text Available Abstract Background Image analysis of microarrays and, in particular, spot quantification and spot quality control, is one of the most important steps in statistical analysis of microarray data. Recent methods of spot quality control are still in early age of development, often leading to underestimation of true positive microarray features and, consequently, to loss of important biological information. Therefore, improving and standardizing the statistical approaches of spot quality control are essential to facilitate the overall analysis of microarray data and subsequent extraction of biological information. Findings We evaluated the performance of two image analysis packages MAIA and GenePix (GP using two complementary experimental approaches with a focus on the statistical analysis of spot quality factors. First, we developed control microarrays with a priori known fluorescence ratios to verify the accuracy and precision of the ratio estimation of signal intensities. Next, we developed advanced semi-automatic protocols of spot quality evaluation in MAIA and GP and compared their performance with available facilities of spot quantitative filtering in GP. We evaluated these algorithms for standardised spot quality analysis in a whole-genome microarray experiment assessing well-characterised transcriptional modifications induced by the transcription regulator SNAI1. Using a set of RT-PCR or qRT-PCR validated microarray data, we found that the semi-automatic protocol of spot quality control we developed with MAIA allowed recovering approximately 13% more spots and 38% more differentially expressed genes (at FDR = 5% than GP with default spot filtering conditions. Conclusion Careful control of spot quality characteristics with advanced spot quality evaluation can significantly increase the amount of confident and accurate data resulting in more meaningful biological conclusions.

  18. Self-replication with magnetic dipolar colloids.

    Science.gov (United States)

    Dempster, Joshua M; Zhang, Rui; Olvera de la Cruz, Monica

    2015-10-01

    Colloidal self-replication represents an exciting research frontier in soft matter physics. Currently, all reported self-replication schemes involve coating colloidal particles with stimuli-responsive molecules to allow switchable interactions. In this paper, we introduce a scheme using ferromagnetic dipolar colloids and preprogrammed external magnetic fields to create an autonomous self-replication system. Interparticle dipole-dipole forces and periodically varying weak-strong magnetic fields cooperate to drive colloid monomers from the solute onto templates, bind them into replicas, and dissolve template complexes. We present three general design principles for autonomous linear replicators, derived from a focused study of a minimalist sphere-dimer magnetic system in which single binding sites allow formation of dimeric templates. We show via statistical models and computer simulations that our system exhibits nonlinear growth of templates and produces nearly exponential growth (low error rate) upon adding an optimized competing electrostatic potential. We devise experimental strategies for constructing the required magnetic colloids based on documented laboratory techniques. We also present qualitative ideas about building more complex self-replicating structures utilizing magnetic colloids.

  19. A Self-Replicating Ligase Ribozyme

    Science.gov (United States)

    Paul, Natasha; Joyce, Gerald F.

    2002-01-01

    A self-replicating molecule directs the covalent assembly of component molecules to form a product that is of identical composition to the parent. When the newly formed product also is able to direct the assembly of product molecules, the self-replicating system can be termed autocatalytic. A self-replicating system was developed based on a ribozyme that catalyzes the assembly of additional copies of Itself through an RNA-catalyzed RNA ligation reaction. The R3C ligase ribozyme was redesigned so that it would ligate two substrates to generate an exact copy of itself, which then would behave in a similar manner. This self-replicating system depends on the catalytic nature of the RNA for the generation of copies. A linear dependence was observed between the initial rate of formation of new copies and the starting concentration of ribozyme, consistent with exponential growth. The autocatalytic rate constant was 0.011 per min, whereas the initial rate of reaction in the absence of pre-existing ribozyme was only 3.3 x 10(exp -11) M per min. Exponential growth was limited, however, because newly formed ribozyme molecules had greater difficulty forming a productive complex with the two substrates. Further optimization of the system may lead to the sustained exponential growth of ribozymes that undergo self-replication.

  20. Spacetime replication of continuous variable quantum information

    Science.gov (United States)

    Hayden, Patrick; Nezami, Sepehr; Salton, Grant; Sanders, Barry C.

    2016-08-01

    The theory of relativity requires that no information travel faster than light, whereas the unitarity of quantum mechanics ensures that quantum information cannot be cloned. These conditions provide the basic constraints that appear in information replication tasks, which formalize aspects of the behavior of information in relativistic quantum mechanics. In this article, we provide continuous variable (CV) strategies for spacetime quantum information replication that are directly amenable to optical or mechanical implementation. We use a new class of homologically constructed CV quantum error correcting codes to provide efficient solutions for the general case of information replication. As compared to schemes encoding qubits, our CV solution requires half as many shares per encoded system. We also provide an optimized five-mode strategy for replicating quantum information in a particular configuration of four spacetime regions designed not to be reducible to previously performed experiments. For this optimized strategy, we provide detailed encoding and decoding procedures using standard optical apparatus and calculate the recovery fidelity when finite squeezing is used. As such we provide a scheme for experimentally realizing quantum information replication using quantum optics.

  1. COPI is required for enterovirus 71 replication.

    Directory of Open Access Journals (Sweden)

    Jianmin Wang

    Full Text Available Enterovirus 71 (EV71, a member of the Picornaviridae family, is found in Asian countries where it causes a wide range of human diseases. No effective therapy is available for the treatment of these infections. Picornaviruses undergo RNA replication in association with membranes of infected cells. COPI and COPII have been shown to be involved in the formation of picornavirus-induced vesicles. Replication of several picornaviruses, including poliovirus and Echovirus 11 (EV11, is dependent on COPI or COPII. Here, we report that COPI, but not COPII, is required for EV71 replication. Replication of EV71 was inhibited by brefeldin A and golgicide A, inhibitors of COPI activity. Furthermore, we found EV71 2C protein interacted with COPI subunits by co-immunoprecipitation and GST pull-down assay, indicating that COPI coatomer might be directed to the viral replication complex through viral 2C protein. Additionally, because the pathway is conserved among different species of enteroviruses, it may represent a novel target for antiviral therapies.

  2. Extremal dynamics in random replicator ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Kärenlampi, Petri P., E-mail: petri.karenlampi@uef.fi

    2015-10-02

    The seminal numerical experiment by Bak and Sneppen (BS) is repeated, along with computations with replicator models, including a greater amount of features. Both types of models do self-organize, and do obey power-law scaling for the size distribution of activity cycles. However species extinction within the replicator models interferes with the BS self-organized critical (SOC) activity. Speciation–extinction dynamics ruins any stationary state which might contain a steady size distribution of activity cycles. The BS-type activity appears as a dissimilar phenomenon in comparison to speciation–extinction dynamics in the replicator system. No criticality is found from the speciation–extinction dynamics. Neither are speciations and extinctions in real biological macroevolution known to contain any diverging distributions, or self-organization towards any critical state. Consequently, biological macroevolution probably is not a self-organized critical phenomenon. - Highlights: • Extremal Dynamics organizes random replicator ecosystems to two phases in fitness space. • Replicator systems show power-law scaling of activity. • Species extinction interferes with Bak–Sneppen type mutation activity. • Speciation–extinction dynamics does not show any critical phase transition. • Biological macroevolution probably is not a self-organized critical phenomenon.

  3. Effects of different levels of Aloe vera gel as an alternative to antibiotic on performance and ileum morphology in broilers

    OpenAIRE

    Ali Mahdavi; Ahmad Zare Shahneh; Abolfazl Zarei; Babak Darabighane

    2011-01-01

    The present study attempts to analyze the effects of different levels of Aloe vera gel as an alternative to antibiotic, on performance and ileum morphology in broilers. Three hundred one-day old Ross 308 male broilers were used on a completely randomized design in 5 groups with 4 replicates, each consisting of 15 broilers. The groups included the control group (basal diet) and three groups with basal diet mixed with different levels of Aloe vera gel (1.5%, 2% and 2.5%). Finally, there was a g...

  4. Synthesis and characterization of nanocrystalline hydroxyapatite gel and its application as scaffold aggregation

    Directory of Open Access Journals (Sweden)

    Leonardo Ribeiro Rodrigues

    2012-12-01

    Full Text Available The sol-gel process is a technique used to synthesize materials from colloidal suspensions and, therefore, is suitable for preparing materials in the nanoscale. In this work hydroxyapatite was used due to its known properties in tissue engineering. Hydroxyapatite Ca10(PO46(OH2 is a bioactive ceramic which is found in the mineral phase of bone tissue and is known for its great potential in tissue engineering applications. For this reason, this material can be applied as particle aggregates on ceramic slurry, coating or film on materials with a poorer biological response than hydroxyapatite. In this work, hydroxyapatite gel was obtained by the sol-gel process and applied as nanoparticle aggregation in the mixture of hydroxyapatite and tricalcium phosphate to form a ceramic slurry. This process is the polymer foam replication technique used to produce scaffolds, which are used in tissue engineering. For HA gel characterization it was used enviromental scanning electron microscopy (ESEM, transmission electron microscopy (TEM, electron energy loss spectroscopy (EELS, scanning electron microscopy (SEM, X-ray diffraction (XRD and X-ray fluorescence (XRF. The crystallite size was calculated from XRD data using the Scherrer equation. The nanoparticles size before firing was approximately 5nm. The crystallite size calculated after calcination was approximately 63 nm. The EELS results showed that calcium phosphate was obtained before firing. After HA gel calcination at 500 ºC the XRD results showed hydroxyapatite with a small content of beta-TCP. The scaffolds obtained by polymer foam replication technique showed a morphology with adequate porosity for tissue engineering.

  5. Stacking gels: A method for maximising output for pulsed-field gel electrophoresis

    Directory of Open Access Journals (Sweden)

    Heng See

    2009-01-01

    Full Text Available Pulsed field gel electrophoresis (PFGE, the gold standard of molecular typing methods, has a major disadvantage of an unusually long electrophoretic time. From the original protocol of 6 days, it was modified to 3 days and subsequently to a single day. We describe the procedure of stacking five to six gels one on top of another in order to increase and maximize the output in a shorter time without compromising the resolution and reproducibility. All the variables that affect pulsed field gels during electrophoresis were taken into consideration. We firstly optimized the parameters to be used and secondly determined whether stacking of five to six gels had any effect on the molecular separation during electrophoresis in comparison with a single gel run. DNA preparation, restriction, electrophoresis, staining and gel documentation was carried out based on previously published methods. Gels were analysed using BioNumerics and dice coefficient and unweighted pair group methods were used to generate dendrograms based on 1.5% tolerance values. Identical band profiles and band resolution-separation were seen in the PFGE patterns with single gel and multiple stacking gels. Cluster analysis further strengthened the fact that results from stacking gels were reproducible and comparable with a single gel run. This method of stacking gels saves time and maximizes the output at the same time. The run time for a single gel was about 28 hours, but with six stacked gels the run time was 54 hours compared with 28 x 6 = 168 hours if they were run separately as single gels thus saving time of 67.86%. Beside the big factor of saving time, stacking gels save resources (electricity, reagents, water, chemicals and working time by increasing the sample throughput in a shorter time without compromising on quality of data. But optimization of working parameters is vital depending on the PFGE system used.

  6. Chromatin Structure and Replication Origins: Determinants Of Chromosome Replication And Nuclear Organization

    OpenAIRE

    Smith, Owen K.; Aladjem, Mirit I.

    2014-01-01

    The DNA replication program is, in part, determined by the epigenetic landscape that governs local chromosome architecture and directs chromosome duplication. Replication must coordinate with other biochemical processes occurring concomitantly on chromatin, such as transcription and remodeling, to insure accurate duplication of both genetic and epigenetic features and to preserve genomic stability. The importance of genome architecture and chromatin looping in coordinating cellular processes ...

  7. Performance of an app measuring spot quality in dried blood spot sampling

    NARCIS (Netherlands)

    Veenhof, Herman

    2016-01-01

    Introduction: The Dried Blood Spot sampling (DBS) method gives patients and health care workers the opportunity for remote sampling using a drop of blood from a fingerprick on a sampling card which can be send to the laboratory by mail. Laboratory analysts frequently reject DBS samples because of

  8. Cold spots in neonatal incubators are hot spots for microbial contamination.

    Science.gov (United States)

    de Goffau, Marcus C; Bergman, Klasien A; de Vries, Hendrik J; Meessen, Nico E L; Degener, John E; van Dijl, Jan Maarten; Harmsen, Hermie J M

    2011-12-01

    Thermal stability is essential for the survival and well-being of preterm neonates. This is achieved in neonatal incubators by raising the ambient temperature and humidity to sufficiently high levels. However, potentially pathogenic microorganisms also can thrive in such warm and humid environments. We therefore investigated whether the level of microbial contamination (i.e., the bacterial load) inside neonatal incubators can be predicted on the basis of their average temperature and relative humidity settings, paying special attention to local temperature differences. Swab samples were taken from the warmest and coldest spots found within Caleo incubators, and these were plated to determine the number of microbial CFU per location. In incubators with high average temperature (≥ 34°C) and relative humidity (≥ 60%) values, the level of microbial contamination was significantly higher at cold spots than at hot spots. This relates to the fact that the local equilibrium relative humidity at cold spots is sufficiently high to sustain microbial growth. The abundance of staphylococci, which are the main causative agents of late-onset sepsis in preterm neonates, was found to be elevated significantly in cold areas. These findings can be used to improve basic incubator hygiene.

  9. Content replication and placement in mobile networks

    CERN Document Server

    La, Chi-Anh; Casetti, Claudio; Chiasserini, Carla-Fabiana; Fiore, Marco

    2011-01-01

    Performance and reliability of content access in mobile networks is conditioned by the number and location of content replicas deployed at the network nodes. Location theory has been the traditional, centralized approach to study content replication: computing the number and placement of replicas in a static network can be cast as a facility location problem. The endeavor of this work is to design a practical solution to the above joint optimization problem that is suitable for mobile wireless environments. We thus seek a replication algorithm that is lightweight, distributed, and reactive to network dynamics. We devise a solution that lets nodes (i) share the burden of storing and providing content, so as to achieve load balancing, and (ii) autonomously decide whether to replicate or drop the information, so as to adapt the content availability to dynamic demands and time-varying network topologies. We evaluate our mechanism through simulation, by exploring a wide range of settings, including different node ...

  10. Evolution of Database Replication Technologies for WLCG

    CERN Document Server

    Baranowski, Zbigniew; Blaszczyk, Marcin; Dimitrov, Gancho; Canali, Luca

    2015-01-01

    In this article we summarize several years of experience on database replication technologies used at WLCG and we provide a short review of the available Oracle technologies and their key characteristics. One of the notable changes and improvement in this area in recent past has been the introduction of Oracle GoldenGate as a replacement of Oracle Streams. We report in this article on the preparation and later upgrades for remote replication done in collaboration with ATLAS and Tier 1 database administrators, including the experience from running Oracle GoldenGate in production. Moreover, we report on another key technology in this area: Oracle Active Data Guard which has been adopted in several of the mission critical use cases for database replication between online and offline databases for the LHC experiments.

  11. Replicating Cardiovascular Condition-Birth Month Associations

    Science.gov (United States)

    Li, Li; Boland, Mary Regina; Miotto, Riccardo; Tatonetti, Nicholas P.; Dudley, Joel T.

    2016-01-01

    Independent replication is vital for study findings drawn from Electronic Health Records (EHR). This replication study evaluates the relationship between seasonal effects at birth and lifetime cardiovascular condition risk. We performed a Season-wide Association Study on 1,169,599 patients from Mount Sinai Hospital (MSH) to compute phenome-wide associations between birth month and CVD. We then evaluated if seasonal patterns found at MSH matched those reported at Columbia University Medical Center. Coronary arteriosclerosis, essential hypertension, angina, and pre-infarction syndrome passed phenome-wide significance and their seasonal patterns matched those previously reported. Atrial fibrillation, cardiomyopathy, and chronic myocardial ischemia had consistent patterns but were not phenome-wide significant. We confirm that CVD risk peaks for those born in the late winter/early spring among the evaluated patient populations. The replication findings bolster evidence for a seasonal birth month effect in CVD. Further study is required to identify the environmental and developmental mechanisms. PMID:27624541

  12. Synchronization of DNA array replication kinetics

    Science.gov (United States)

    Manturov, Alexey O.; Grigoryev, Anton V.

    2016-04-01

    In the present work we discuss the features of the DNA replication kinetics at the case of multiplicity of simultaneously elongated DNA fragments. The interaction between replicated DNA fragments is carried out by free protons that appears at the every nucleotide attachment at the free end of elongated DNA fragment. So there is feedback between free protons concentration and DNA-polymerase activity that appears as elongation rate dependence. We develop the numerical model based on a cellular automaton, which can simulate the elongation stage (growth of DNA strands) for DNA elongation process with conditions pointed above and we study the possibility of the DNA polymerases movement synchronization. The results obtained numerically can be useful for DNA polymerase movement detection and visualization of the elongation process in the case of massive DNA replication, eg, under PCR condition or for DNA "sequencing by synthesis" sequencing devices evaluation.

  13. GFLV replication in electroporated grapevine protoplasts.

    Science.gov (United States)

    Valat; Toutain; Courtois; Gaire; Decout; Pinck; Mauro; Burrus

    2000-06-29

    Grapevine fanleaf virus (GFLV), responsible for the economically important court-noué disease, is exclusively transmitted to its natural host in the vineyards through Xiphinema nematodes. We have developed direct inoculation of GFLV into grapevine through protoplast electroporation. Protoplasts were isolated from mesophyll of in vitro-grown plants and from embryogenic cell suspensions. Permeation conditions were determined by monitoring calcein uptake. Low salt poration medium was selected. Electrical conditions leading to strong transient gene expression were also tested for GFLV inoculation (isolate F13). GFLV replication was detected with either virus particles (2 µg) or viral RNA (10 ng) in both protoplast populations, as shown by anti-P38 Western blotting. Direct inoculation and replication were also observed with Arabis mosaic virus (ArMV), a closely related nepovirus, as well as with another GFLV isolate. These results will be valuable in grapevine biotechnology, for GFLV replication studies, transgenic plant screening for GFLV resistance, and biorisk evaluation.

  14. Spinning-Spot Shadowless TIRF Microscopy.

    Directory of Open Access Journals (Sweden)

    Kyle L Ellefsen

    Full Text Available Total internal reflection fluorescence (TIRF microscopy is a powerful tool for visualizing near-membrane cellular structures and processes, including imaging of local Ca2+ transients with single-channel resolution. TIRF is most commonly implemented in epi-fluorescence mode, whereby laser excitation light is introduced at a spot near the periphery of the back focal plane of a high numerical aperture objective lens. However, this approach results in an irregular illumination field, owing to interference fringes and scattering and shadowing by cellular structures. We describe a simple system to circumvent these limitations, utilizing a pair of galvanometer-driven mirrors to rapidly spin the laser spot in a circle at the back focal plane of the objective lens, so that irregularities average out during each camera exposure to produce an effectively uniform field. Computer control of the mirrors enables precise scanning at 200 Hz (5ms camera exposure times or faster, and the scan radius can be altered on a frame-by-frame basis to achieve near-simultaneous imaging in TIRF, widefield and 'skimming plane' imaging modes. We demonstrate the utility of the system for dynamic recording of local inositol trisphosphate-mediated Ca2+ signals and for imaging the redistribution of STIM and Orai proteins during store-operated Ca2+ entry. We further anticipate that it will be readily applicable for numerous other near-membrane studies, especially those involving fast dynamic processes.

  15. Spinning-Spot Shadowless TIRF Microscopy

    Science.gov (United States)

    Ellefsen, Kyle L.; Dynes, Joseph L.; Parker, Ian

    2015-01-01

    Total internal reflection fluorescence (TIRF) microscopy is a powerful tool for visualizing near-membrane cellular structures and processes, including imaging of local Ca2+ transients with single-channel resolution. TIRF is most commonly implemented in epi-fluorescence mode, whereby laser excitation light is introduced at a spot near the periphery of the back focal plane of a high numerical aperture objective lens. However, this approach results in an irregular illumination field, owing to interference fringes and scattering and shadowing by cellular structures. We describe a simple system to circumvent these limitations, utilizing a pair of galvanometer-driven mirrors to rapidly spin the laser spot in a circle at the back focal plane of the objective lens, so that irregularities average out during each camera exposure to produce an effectively uniform field. Computer control of the mirrors enables precise scanning at 200 Hz (5ms camera exposure times) or faster, and the scan radius can be altered on a frame-by-frame basis to achieve near-simultaneous imaging in TIRF, widefield and ‘skimming plane’ imaging modes. We demonstrate the utility of the system for dynamic recording of local inositol trisphosphate-mediated Ca2+ signals and for imaging the redistribution of STIM and Orai proteins during store-operated Ca2+ entry. We further anticipate that it will be readily applicable for numerous other near-membrane studies, especially those involving fast dynamic processes. PMID:26308212

  16. Method for laser spot welding monitoring

    Science.gov (United States)

    Manassero, Giorgio

    1994-09-01

    As more powerful solid state laser sources appear on the market, new applications become technically possible and important from the economical point of view. For every process a preliminary optimization phase is necessary. The main parameters, used for a welding application by a high power Nd-YAG laser, are: pulse energy, pulse width, repetition rate and process duration or speed. In this paper an experimental methodology, for the development of an electrooptical laser spot welding monitoring system, is presented. The electromagnetic emission from the molten pool was observed and measured with appropriate sensors. The statistical method `Parameter Design' was used to obtain an accurate analysis of the process parameter that influence process results. A laser station with a solid state laser coupled to an optical fiber (1 mm in diameter) was utilized for the welding tests. The main material used for the experimental plan was zinc coated steel sheet 0.8 mm thick. This material and the related spot welding technique are extensively used in the automotive industry, therefore, the introduction of laser technology in production line will improve the quality of the final product. A correlation, between sensor signals and `through or not through' welds, was assessed. The investigation has furthermore shown the necessity, for the modern laser production systems, to use multisensor heads for process monitoring or control with more advanced signal elaboration procedures.

  17. Laser induced single spot oxidation of titanium

    Science.gov (United States)

    Jwad, Tahseen; Deng, Sunan; Butt, Haider; Dimov, S.

    2016-11-01

    Titanium oxides have a wide range of applications in industry, and they can be formed on pure titanium using different methods. Laser-induced oxidation is one of the most reliable methods due to its controllability and selectivity. Colour marking is one of the main applications of the oxidation process. However, the colourizing process based on laser scanning strategies is limited by the relative large processing area in comparison to the beam size. Single spot oxidation of titanium substrates is proposed in this research in order to increase the resolution of the processed area and also to address the requirements of potential new applications. The method is applied to produce oxide films with different thicknesses and hence colours on titanium substrates. High resolution colour image is imprinted on a sheet of pure titanium by converting its pixels' colours into laser parameter settings. Optical and morphological periodic surface structures are also produced by an array of oxide spots and then analysed. Two colours have been coded into one field and the dependencies of the reflected colours on incident and azimuthal angles of the light are discussed. The findings are of interest to a range of application areas, as they can be used to imprint optical devices such as diffusers and Fresnel lenses on metallic surfaces as well as for colour marking.

  18. Suppression of Adenovirus Replication by Cardiotonic Steroids.

    Science.gov (United States)

    Grosso, Filomena; Stoilov, Peter; Lingwood, Clifford; Brown, Martha; Cochrane, Alan

    2017-02-01

    The dependence of adenovirus on the host pre-RNA splicing machinery for expression of its complete genome potentially makes it vulnerable to modulators of RNA splicing, such as digoxin and digitoxin. Both drugs reduced the yields of four human adenoviruses (HAdV-A31, -B35, and -C5 and a species D conjunctivitis isolate) by at least 2 to 3 logs by affecting one or more steps needed for genome replication. Immediate early E1A protein levels are unaffected by the drugs, but synthesis of the delayed protein E4orf6 and the major late capsid protein hexon is compromised. Quantitative reverse transcription-PCR (qRT-PCR) analyses revealed that both drugs altered E1A RNA splicing (favoring the production of 13S over 12S RNA) early in infection and partially blocked the transition from 12S and 13S to 9S RNA at late stages of virus replication. Expression of multiple late viral protein mRNAs was lost in the presence of either drug, consistent with the observed block in viral DNA replication. The antiviral effect was dependent on the continued presence of the drug and was rapidly reversible. RIDK34, a derivative of convallotoxin, although having more potent antiviral activity, did not show an improved selectivity index. All three drugs reduced metabolic activity to some degree without evidence of cell death. By blocking adenovirus replication at one or more steps beyond the onset of E1A expression and prior to genome replication, digoxin and digitoxin show potential as antiviral agents for treatment of serious adenovirus infections. Furthermore, understanding the mechanism(s) by which digoxin and digitoxin inhibit adenovirus replication will guide the development of novel antiviral therapies.

  19. High internal phase emulsion gels (HIPE-gels) created through assembly of natural oil bodies

    NARCIS (Netherlands)

    Nikiforidis, C.V.; Scholten, E.

    2015-01-01

    A natural emulsion was used to create a high internal phase emulsion (HIPE) gel with elastic properties, indicated by shear elastic moduli between 102 and 105 Pa. The elasticity of the gel network was provided from a 2D-gel network of proteins which were naturally adsorbed at the interface of an oil

  20. Categorization of rheological scaling models for particle gels applied to casein gels

    NARCIS (Netherlands)

    Mellema, M.; Opheusden, van J.H.J.; Vliet, van T.

    2002-01-01

    Rennet-induced casein gels made from skim milk were studied rheologically. A scaling model or framework for describing the rheological behavior of gels is discussed and used for classification of the structure of casein gels. There are two main parameters in the model that describe the number of def

  1. Viscoelastic Properties of Vitreous Gel

    Science.gov (United States)

    Pirouz Kavehpour, H.; Sharif-Kashani, Pooria

    2010-11-01

    We studied the rheological properties of porcine vitreous humor using a stressed-control shear rheometer. All experiments were performed in a closed environment at body temperature to mimic in-vivo conditions. We modeled the creep deformation using a two-element retardation spectrum model. By associating each element of the model to an individual biopolymeric system in the vitreous gel, a separate response to the applied stress was obtained from each component. The short time scale was associated with the collagen structure, while the longer time scale was related to the microfibrilis and hyaluronan network. We were able to distinguish the role of each main component from the overall rheological properties. Knowledge of this correlation enables us to relate the physical properties of vitreous to its pathology, as well as optimize surgical procedures such as vitrectomy.

  2. Chitosan: Gels and Interfacial Properties

    Directory of Open Access Journals (Sweden)

    Julie Nilsen-Nygaard

    2015-03-01

    Full Text Available Chitosan is a unique biopolymer in the respect that it is abundant, cationic, low-toxic, non-immunogenic and biodegradable. The relative occurrence of the two monomeric building units (N-acetyl-glucosamine and d-glucosamine is crucial to whether chitosan is predominantly an ampholyte or predominantly a polyelectrolyte at acidic pH-values. The chemical composition is not only crucial to its surface activity properties, but also to whether and why chitosan can undergo a sol–gel transition. This review gives an overview of chitosan hydrogels and their biomedical applications, e.g., in tissue engineering and drug delivery, as well as the chitosan’s surface activity and its role in emulsion formation, stabilization and destabilization. Previously unpublished original data where chitosan acts as an emulsifier and flocculant are presented and discussed, showing that highly-acetylated chitosans can act both as an emulsifier and as a flocculant.

  3. Meteorology of Jupiter's Equatorial Hot Spots and Plumes from Cassini

    CERN Document Server

    Choi, David S; Vasavada, Ashwin R; Simon-Miller, Amy A

    2013-01-01

    We present an updated analysis of Jupiter's equatorial meteorology from Cassini observations. For two months preceding the spacecraft's closest approach, the Imaging Science Subsystem (ISS) onboard regularly imaged the atmosphere. We created time-lapse movies from this period in order to analyze the dynamics of equatorial hot spots and their interactions with adjacent latitudes. Hot spots are quasi-stable, rectangular dark areas on visible-wavelength images, with defined eastern edges that sharply contrast with surrounding clouds, but diffuse western edges serving as nebulous boundaries with adjacent equatorial plumes. Hot spots exhibit significant variations in size and shape over timescales of days and weeks. Some of these changes correspond with passing vortex systems from adjacent latitudes interacting with hot spots. Strong anticyclonic gyres present to the south and southeast of the dark areas appear to circulate into hot spots. Impressive, bright white plumes occupy spaces in between hot spots. Compact...

  4. The replication of expansive production knowledge

    DEFF Research Database (Denmark)

    Wæhrens, Brian Vejrum; Yang, Cheng; Madsen, Erik Skov

    2012-01-01

    . Design/methodology/approach – Two case studies are introduced. Empirical data were collected over a period of two years based on interviews and participating observations. Findings – The findings show that (1) knowledge transfer within the replication of a production line is a stepwise expansive process......Purpose – With the aim to support offshore production line replication, this paper specifically aims to explore the use of templates and principles to transfer expansive productive knowledge embedded in a production line and understand the contingencies that influence the mix of these approaches...... and principles to transfer productive knowledge in a specific context, which, in this paper, is a production line....

  5. Chromatin challenges during DNA replication and repair

    DEFF Research Database (Denmark)

    Groth, Anja; Rocha, Walter; Verreault, Alain

    2007-01-01

    Inheritance and maintenance of the DNA sequence and its organization into chromatin are central for eukaryotic life. To orchestrate DNA-replication and -repair processes in the context of chromatin is a challenge, both in terms of accessibility and maintenance of chromatin organization. To meet...... the challenge of maintenance, cells have evolved efficient nucleosome-assembly pathways and chromatin-maturation mechanisms that reproduce chromatin organization in the wake of DNA replication and repair. The aim of this Review is to describe how these pathways operate and to highlight how the epigenetic...

  6. Involvement of Autophagy in Coronavirus Replication

    Directory of Open Access Journals (Sweden)

    Paul Britton

    2012-11-01

    Full Text Available Coronaviruses are single stranded, positive sense RNA viruses, which induce the rearrangement of cellular membranes upon infection of a host cell. This provides the virus with a platform for the assembly of viral replication complexes, improving efficiency of RNA synthesis. The membranes observed in coronavirus infected cells include double membrane vesicles. By nature of their double membrane, these vesicles resemble cellular autophagosomes, generated during the cellular autophagy pathway. In addition, coronavirus infection has been demonstrated to induce autophagy. Here we review current knowledge of coronavirus induced membrane rearrangements and the involvement of autophagy or autophagy protein microtubule associated protein 1B light chain 3 (LC3 in coronavirus replication.

  7. Spectrum of antimicrobial activity and user acceptability of the hand disinfectant agent Sterillium Gel.

    Science.gov (United States)

    Kampf, G; Rudolf, M; Labadie, J-C; Barrett, S P

    2002-10-01

    The antimicrobial efficacy of alcohol-based hand gels has been shown to be significantly less than liquid hand rubs probably because of a lower concentration of alcohol. Sterillium Gel is the first hand gel with 85% ethanol. Its antimicrobial efficacy and user acceptability was studied. Bactericidal activity was tested according to prEN 12054 against Staphylococcus aureus, Enterococcus hirae, Pseudomonas aeruginosa and Escherichia coli (suspension test) and EN 1500 (15 volunteers; four replicates), fungicidal activity according to EN 1275 against Candida albicans and spores of Aspergillus niger (suspension test) and tuberculocidal activity against Mycobacterium terrae using the DGHM suspension test. Virucidal activity was determined in suspension tests based on reduction of infectivity with and without interfering substances (10% fetal calf serum; 0.3% erythrocytes and 0.3% bovine serum albumin). Ninety-six healthcare workers in hospitals in France and the UK used the gel for four weeks and assessed it by filling out a questionnaire. The gel was bactericidal (a reduction factor of > 10(5)-fold), tuberculocidal (reduction factor > 10(5)) and fungicidal (reduction factor > 10(4)) in 30 s. Irrespective of interfering substances the gel inactivated orthopoxvirus and herpes simplex virus type 1 and 2 in 15 s, adenovirus in 2 min, poliovirus in 3 min and papovavirus in 15 min by a factor of > 10(4)-fold. Rotavirus and human immunodeficiency virus were inactivated in 30 s (without interfering substances). Under practical use conditions it was as effective in 30 s as the reference alcohol in 60 s. Most users described the tackiness, aggregation, skin feeling after use and smell as positive or acceptable. A total of 65.6% assessed the new gel to be better than a comparator irrespective of its type (gel or liquid). Overall Sterillium Gel had a unique spectrum of antimicrobial activity. It is probably the first alcohol-based hand gel to pass EN 1500 in 30 s. Due to the

  8. Replication, recombination, and repair: going for the gold.

    Science.gov (United States)

    Klein, Hannah L; Kreuzer, Kenneth N

    2002-03-01

    DNA recombination is now appreciated to be integral to DNA replication and cell survival. Recombination allows replication to successfully maneuver through the roadblocks of damaged or collapsed replication forks. The signals and controls that permit cells to transition between replication and recombination modes are now being identified.

  9. Direct visualization of replication dynamics in early zebrafish embryos.

    Science.gov (United States)

    Kuriya, Kenji; Higashiyama, Eriko; Avşar-Ban, Eriko; Okochi, Nanami; Hattori, Kaede; Ogata, Shin; Takebayashi, Shin-Ichiro; Ogata, Masato; Tamaru, Yutaka; Okumura, Katsuzumi

    2016-05-01

    We analyzed DNA replication in early zebrafish embryos. The replicating DNA of whole embryos was labeled with the thymidine analog 5-ethynyl-2'-deoxyuridine (EdU), and spatial regulation of replication sites was visualized in single embryo-derived cells. The results unveiled uncharacterized replication dynamics during zebrafish early embryogenesis.

  10. Bier’s spots with onset in childhood*

    Science.gov (United States)

    Portocarrero, Larissa Karine Leite; Saraiva, Maria Isabel Ramos; Barbosa, Marcella Amaral Horta; Veronez, Isis Suga; Swiczar, Bethania Cabral Cavalli; Valente, Neusa Yuriko Sakai

    2016-01-01

    Bier spots are small, irregular, hypopigmented macules that are usually found on the arms and legs. The macules disappear when the limb is raised. Bier spots have been reported in association with a number of conditions but there is no consistent association to specific desease. Although they usually affect young adults, we report a case of Bier spots that began in childhood. As an asymptomatic and possibly transitional condition, the disease does not require treatment.

  11. Dominant inheritance of overo spotting in paint horses.

    Science.gov (United States)

    Bowling, A T

    1994-01-01

    Analysis of selected studbook records of the American Paint Horse Association, consisting of 687 foals sired by 13 overo stallions from non-overo mares, supports the inheritance of overo spotting as an autosomal dominant gene. More than one gene may control patterns registered as overo. Additional studies are necessary to explain the sporadic occurrence of overo spotting from nonspotted quarter horse parents and to confirm the inheritance of overo spotting in other breeds.

  12. An improved method to spot-weld difficult junctions

    Science.gov (United States)

    Ferrenz, Elizabeth E.; Amare, Andinet; Arumainayagam, Christopher R.

    2001-12-01

    Recent advances in spot-welding technology such as high frequency direct current inverter welders provide an improved and reproducible method to spot-weld difficult junctions. The importance of removing the oxide layers on metal surfaces, accurately delivering the weld pulse profile, and controlling the force applied to the materials during the welding process are discussed in the context of resistance spot-welding a molybdenum crystal to a tantalum loop and attaching a tungsten-rhenium thermocouple to the crystal.

  13. Modeling the Dynamics of Chinese Spot Interest Rates

    OpenAIRE

    Yongmiao Hong; Hai Lin; Shouyang Wang

    2013-01-01

    Understanding the dynamics of spot interest rates is important for derivatives pricing, risk management, interest rate liberalization, and macroeconomic control. Based on a daily data of Chinese 7-day repo rates from July 22, 1996 to August 26, 2004, we estimate and test a variety of popular spot rate models, including single factor diffusion, GARCH, Markov regime switching and jump diffusion models, to examine how well they can capture the dynamics of the Chinese spot rates and whether the d...

  14. Development and application of antibody microarray for white spot syndrome virus detection in shrimp

    Institute of Scientific and Technical Information of China (English)

    XU Xiaoli; SHENG Xiuzhen; ZHAN Wenbin

    2011-01-01

    Detecting white spot syndrome virus (WSSV) in shrimp in high efficiency and veracity is important for disease prevention in aquaculture.Antibody-based microarray is a novel proteomic technology that can meet the requirements.In this study,we developed an antibody microarray for WSSV-detection in a specific and parallel way at multiple samples.First,seven slides each with different modifications were characterized by atomic force microscope,and were compared in the efficiency of immobilizing proteins.Of the seven,3-dimensional structured agarose gel-modified slides were chosen appropriate for the microarray for having higher signal value and superior spot size.A purified rabbit anti-WSSV antibody was arrayed as the capture antibody of the microarray on the agarose gel-modified slides,and then the microarray slides were incubated in the tissue homogenate of sampled shrimp and the antibody-antigen complex was detected by Cy3-conjugated anti-WSSV monoclonal antibody.The results were measured by a laser chipscanner and analyzed with software.To obtain satisfied fluorescence signal intensity,optimal conditions were searched.The detection limit of the antibody microarray for WSSV is 0.62 μg/mL,with a proven long shelf life for 6 months at 4℃ or 8 months at -20℃.Furthermore,concordance between antibody microarray and traditional indirect ELISA reached 100% for WSSV detection.These results suggest that the antibody microarray could be served as an effective tool for diagnostic and epidemiological studies of WSSV.

  15. Spatial regulation and organization of DNA replication within the nucleus.

    Science.gov (United States)

    Natsume, Toyoaki; Tanaka, Tomoyuki U

    2010-01-01

    Duplication of chromosomal DNA is a temporally and spatially regulated process. The timing of DNA replication initiation at various origins is highly coordinated; some origins fire early and others late during S phase. Moreover, inside the nuclei, the bulk of DNA replication is physically organized in replication factories, consisting of DNA polymerases and other replication proteins. In this review article, we discuss how DNA replication is organized and regulated spatially within the nucleus and how this spatial organization is linked to temporal regulation. We focus on DNA replication in budding yeast and fission yeast and, where applicable, compare yeast DNA replication with that in bacteria and metazoans.

  16. Regulation of eukaryotic DNA replication and nuclear structure

    Institute of Scientific and Technical Information of China (English)

    WUJIARUI

    1999-01-01

    In eukaryote,nuclear structure is a key component for the functions of eukaryotic cells.More and more evidences show that the nuclear structure plays important role in regulating DNA replication.The nuclear structure provides a physical barrier for the replication licensing,participates in the decision where DNA replication initiates,and organizes replication proteins as replication factory for DNA replication.Through these works,new concepts on the regulation of DNA replication have emerged,which will be discussed in this minireview.

  17. Using Greener Gels to Explore Rheology

    Science.gov (United States)

    Garrett, Brendan; Matharu, Avtar S.; Hurst, Glenn A.

    2017-01-01

    A laboratory experiment was developed to investigate the rheological properties of a green calcium-cross-linked alginate gel as an alternative to the traditional borax-cross-linked poly(vinyl alcohol) gel. As borax is suspected of damaging fertility and the unborn child, a safe, green alternative is necessary. The rheological properties of a…

  18. Halogen-bonding-triggered supramolecular gel formation.

    Science.gov (United States)

    Meazza, Lorenzo; Foster, Jonathan A; Fucke, Katharina; Metrangolo, Pierangelo; Resnati, Giuseppe; Steed, Jonathan W

    2013-01-01

    Supramolecular gels are topical soft materials involving the reversible formation of fibrous aggregates using non-covalent interactions. There is significant interest in controlling the properties of such materials by the formation of multicomponent systems, which exhibit non-additive properties emerging from interaction of the components. The use of hydrogen bonding to assemble supramolecular gels in organic solvents is well established. In contrast, the use of halogen bonding to trigger supramolecular gel formation in a two-component gel ('co-gel') is essentially unexplored, and forms the basis for this study. Here, we show that halogen bonding between a pyridyl substituent in a bis(pyridyl urea) and 1,4-diiodotetrafluorobenzene brings about gelation, even in polar media such as aqueous methanol and aqueous dimethylsulfoxide. This demonstrates that halogen bonding is sufficiently strong to interfere with competing gel-inhibitory interactions and create a 'tipping point' in gel assembly. Using this concept, we have prepared a halogen bond donor bis(urea) gelator that forms co-gels with halogen bond acceptors.

  19. Recrystallization of amylopectin in concentrated starch gels

    NARCIS (Netherlands)

    Keetels, CJAM; Oostergetel, GT; vanVliet, T

    1996-01-01

    The relation between the recrystallization of amylopectin and the increase in stiffness of starch gels during storage was studied by various techniques. From transmission electron microscopy it was concluded that the size of the crystalline domains in retrograded 30% w/w potato starch gels was about

  20. Cd(II) Speciation in alginate gels

    NARCIS (Netherlands)

    Davis, T.A.; Kalis, E.J.J.; Pinheiro, J.P.; Town, R.M.; Leeuwen, van H.P.

    2008-01-01

    Polysaccharides, such as those occurring in cell walls and biofilms, play an important role in metal speciation in natural aqueous systems. This work describes the speciation of Cd(II) in alginate gels chosen as a model system for biogels. The gels are formed by bridging calcium ions at junction zon

  1. Serum release boosts sweetness intensity in gels

    NARCIS (Netherlands)

    Sala, G.; Stieger, M.A.; Velde, van de F.

    2010-01-01

    This paper describes the effect of serum release on sweetness intensity in mixed whey protein isolate/gellan gum gels. The impact of gellan gum and sugar concentration on microstructure, permeability, serum release and large deformation properties of the gels was determined. With increasing gellan

  2. Stiffening in gels containing whey protein isolate

    NARCIS (Netherlands)

    Purwanti, N.; Veen, van der E.; Goot, van der A.J.; Boom, R.M.

    2013-01-01

    Gels made only from whey protein isolate (WPI) stiffened over the first few days of storage, after which the textural properties remained nearly constant. However, protein gels containing WPI microparticles, at the same total protein content, stiffened over a longer period than those without micropa

  3. Responsive molecular gels. : Surface Chemistry and Colloids

    NARCIS (Netherlands)

    de Jong, Jaap J. D.; Feringa, Bernard; van Esch, Jan

    2006-01-01

    A review discusses the chemo-responsive gels and physico-responsive gels. Phys. low mol. mass responsive gelators are interesting mols. with many potential applications in areas such as catalysis, sensor and sepn. technol., drug delivery, and biomedicine. In a relatively short period, a wide variety

  4. Flow of colloidal suspensions and gels

    Science.gov (United States)

    Zia, Roseanna

    Our recent studies of yield of colloidal gels under shear show that yield in such gels occurs in distinct stages. Under fixed stress, yield follows a finite delay period of slow solid-like creep. Post yield, the gel fluidizes and may undergo long-time viscous flow or, in some cases, may re-solidify. Under imposed strain rate, the transition from equilibrium to long-time flow is characterized by one or more stress overshoots, signifying a yield process here as well. These rheological changes are accompanied by evolution in morphology and dynamics of the gel network. Similar regimes have been observed in gels subjected to gravitational forcing; the gel initially supports its own weight, or perhaps undergoes slow, weak compaction. This may be followed by a sudden transition to rapid compaction or sedimentation. Various models have been put forth to explain these behaviors based on structural evolution, but this detail is difficult to observe in experiment. Here we examine the detailed microstructural evolution and rheology of reversible colloidal gels as they deform under gravity, identifying the critical buoyant force at which yield occurs, the role played by ongoing gel coarsening, and similarities and differences compared to yield under shear. We gratefully acknowledge the support of the NSF XSEDE Computational Resource, the NSF Early CAREER Program, and the Office of Naval Research Young Investigator Program.

  5. Responsive molecular gels. : Surface Chemistry and Colloids

    NARCIS (Netherlands)

    de Jong, Jaap J. D.; Feringa, Bernard; van Esch, Jan

    2006-01-01

    A review discusses the chemo-responsive gels and physico-responsive gels. Phys. low mol. mass responsive gelators are interesting mols. with many potential applications in areas such as catalysis, sensor and sepn. technol., drug delivery, and biomedicine. In a relatively short period, a wide variety

  6. Assembly of Slx4 signaling complexes behind DNA replication forks.

    Science.gov (United States)

    Balint, Attila; Kim, TaeHyung; Gallo, David; Cussiol, Jose Renato; Bastos de Oliveira, Francisco M; Yimit, Askar; Ou, Jiongwen; Nakato, Ryuichiro; Gurevich, Alexey; Shirahige, Katsuhiko; Smolka, Marcus B; Zhang, Zhaolei; Brown, Grant W

    2015-08-13

    Obstructions to replication fork progression, referred to collectively as DNA replication stress, challenge genome stability. In Saccharomyces cerevisiae, cells lacking RTT107 or SLX4 show genome instability and sensitivity to DNA replication stress and are defective in the completion of DNA replication during recovery from replication stress. We demonstrate that Slx4 is recruited to chromatin behind stressed replication forks, in a region that is spatially distinct from that occupied by the replication machinery. Slx4 complex formation is nucleated by Mec1 phosphorylation of histone H2A, which is recognized by the constitutive Slx4 binding partner Rtt107. Slx4 is essential for recruiting the Mec1 activator Dpb11 behind stressed replication forks, and Slx4 complexes are important for full activity of Mec1. We propose that Slx4 complexes promote robust checkpoint signaling by Mec1 by stably recruiting Dpb11 within a discrete domain behind the replication fork, during DNA replication stress.

  7. Fatigue crack growth retardation in spot heated mild steel sheet

    Indian Academy of Sciences (India)

    B B Verma; P K Ray

    2002-08-01

    A fatigue crack can be effectively retarded by heating a spot near the crack tip under nil remote stress condition. The subcritical spot heating at a proper position modifies the crack growth behaviour in a way, more or less, similar to specimen subjected to overload spike. It is observed that the extent of crack growth retardation increases with increasing level of overload as well as with increasing spot temperature. It is also observed that modification in crack growth behaviour is a function of location of heating spot and maximum retardation is observed at + 5 position.

  8. Barley seed proteomics from spots to structures

    DEFF Research Database (Denmark)

    Finnie, Christine; Svensson, Birte

    2009-01-01

    with information from rice and other cereals facilitate identification of barley proteins. Several hundred barley seed proteins are identified and lower abundance proteins including membrane proteins are now being analysed. In the present review we focus on variation in protein profiles of seed tissues during...... forms on 2D-gels. Specific protein families, including peroxidases and alpha-amylases have been subjected to in-depth analysis resulting in characterisation of different isozymes, post-translational. modifications and processing. A functional proteomics study focusing on the seed thioredoxin system has...

  9. Susceptibility of Chinese Perch Brain (CPB) Cell and Mandarin Fish to Red-Spotted Grouper Nervous Necrosis Virus (RGNNV) Infection.

    Science.gov (United States)

    Tu, Jiagang; Chen, Wenjie; Fu, Xiaozhe; Lin, Qiang; Chang, Ouqin; Zhao, Lijuan; Lan, Jiangfeng; Li, Ningqiu; Lin, Li

    2016-05-19

    Nervous necrosis virus (NNV) is the causative agent of viral encephalopathy and retinopathy (VER), a neurological disease responsible for high mortality of fish species worldwide. Taking advantage of our established Chinese perch brain (CPB) cell line derived from brain tissues of Mandarin fish (Siniperca chuatsi), the susceptibility of CPB cell to Red-Spotted Grouper nervous necrosis virus (RGNNV) was evaluated. The results showed that RGNNV replicated well in CPB cells, resulting in cellular apoptosis. Moreover, the susceptibility of Mandarin fish to RGNNV was also evaluated. Abnormal swimming was observed in RGNNV-infected Mandarin fish. In addition, the cellular vacuolation and viral particles were also observed in brain tissues of RGNNV-infected Mandarin fish by Hematoxylin-eosin staining or electronic microscopy. The established RGNNV susceptible brain cell line from freshwater fish will pave a new way for the study of the pathogenicity and replication of NNV in the future.

  10. Susceptibility of Chinese Perch Brain (CPB Cell and Mandarin Fish to Red-Spotted Grouper Nervous Necrosis Virus (RGNNV Infection

    Directory of Open Access Journals (Sweden)

    Jiagang Tu

    2016-05-01

    Full Text Available Nervous necrosis virus (NNV is the causative agent of viral encephalopathy and retinopathy (VER, a neurological disease responsible for high mortality of fish species worldwide. Taking advantage of our established Chinese perch brain (CPB cell line derived from brain tissues of Mandarin fish (Siniperca chuatsi, the susceptibility of CPB cell to Red-Spotted Grouper nervous necrosis virus (RGNNV was evaluated. The results showed that RGNNV replicated well in CPB cells, resulting in cellular apoptosis. Moreover, the susceptibility of Mandarin fish to RGNNV was also evaluated. Abnormal swimming was observed in RGNNV-infected Mandarin fish. In addition, the cellular vacuolation and viral particles were also observed in brain tissues of RGNNV-infected Mandarin fish by Hematoxylin-eosin staining or electronic microscopy. The established RGNNV susceptible brain cell line from freshwater fish will pave a new way for the study of the pathogenicity and replication of NNV in the future.

  11. Effects of different levels of Aloe vera gel as an alternative to antibiotic on performance and ileum morphology in broilers

    Directory of Open Access Journals (Sweden)

    Ali Mahdavi

    2011-07-01

    Full Text Available The present study attempts to analyze the effects of different levels of Aloe vera gel as an alternative to antibiotic, on performance and ileum morphology in broilers. Three hundred one-day old Ross 308 male broilers were used on a completely randomized design in 5 groups with 4 replicates, each consisting of 15 broilers. The groups included the control group (basal diet and three groups with basal diet mixed with different levels of Aloe vera gel (1.5%, 2% and 2.5%. Finally, there was a group with basal diet plus 15 ppm antibiotic virginiamycin. The results obtained regarding performance of the broilers showed that Aloe vera gel groups brought about higher body weight gain and feed intake compared to the control group; however, no significant difference was observed in feed conversion ratio between the groups treated by Aloe vera gel and the control group (P>0.05. Although the antibiotic group showed better performance and heavier dressing percentage than the Aloe vera gel and the control groups, no significant difference was seen between the group treated by 2% Aloe vera gel and the antibiotic group regarding body weight gain, feed conversion ratio and dressing percentage (P>0.05. Among the Aloe vera gel groups, the 2% Aloe vera gel group had the largest villus height and the greatest villus height to crypt depth ratio compared to the antibiotic group (PAloe vera gel treatment may be recommended to achieve the best performance in broilers as an alternative to antibiotic growth promoter.

  12. Catalytic control over supramolecular gel formation.

    Science.gov (United States)

    Boekhoven, Job; Poolman, Jos M; Maity, Chandan; Li, Feng; van der Mee, Lars; Minkenberg, Christophe B; Mendes, Eduardo; van Esch, Jan H; Eelkema, Rienk

    2013-05-01

    Low-molecular-weight gels show great potential for application in fields ranging from the petrochemical industry to healthcare and tissue engineering. These supramolecular gels are often metastable materials, which implies that their properties are, at least partially, kinetically controlled. Here we show how the mechanical properties and structure of these materials can be controlled directly by catalytic action. We show how in situ catalysis of the formation of gelator molecules can be used to accelerate the formation of supramolecular hydrogels, which drastically enhances their resulting mechanical properties. Using acid or nucleophilic aniline catalysis, it is possible to make supramolecular hydrogels with tunable gel-strength in a matter of minutes, under ambient conditions, starting from simple soluble building blocks. By changing the rate of formation of the gelator molecules using a catalyst, the overall rate of gelation and the resulting gel morphology are affected, which provides access to metastable gel states with improved mechanical strength and appearance despite an identical gelator composition.

  13. On shear rheology of gel propellants

    Energy Technology Data Exchange (ETDEWEB)

    Rahimi, Shai; Peretz, Arie [RAFAEL, MANOR Propulsion and Explosive Systems Division, Haifa (Israel); Natan, Benveniste [Faculty of Aerospace Engineering, Technion - Israel Institute of Technology, Haifa (Israel)

    2007-04-15

    Selected fuel, oxidizer and simulant gels were prepared and rheologically characterized using a rotational rheometer. For fuel gelation both organic and inorganic gellants were utilized, whereas oxidizers and simulants were gelled with addition of silica and polysaccharides, respectively. The generalized Herschel-Bulkley constitutive model was found to most adequately represent the gels studied. Hydrazine-based fuels, gelled with polysaccharides, were characterized as shear-thinning pseudoplastic fluids with low shear yield stress, whereas inhibited red-fuming nitric acid (IRFNA) and hydrogen peroxide oxidizers, gelled with silica, were characterized as yield thixotropic fluids with significant shear yield stress. Creep tests were conducted on two rheological types of gels with different gellant content and the results were fitted by Burgers-Kelvin viscoelastic constitutive model. The effect of temperature on the rheological properties of gel propellant simulants was also investigated. A general rheological classification of gel propellants and simulants is proposed. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  14. Controlling the Morphology of Carbon Gels

    Directory of Open Access Journals (Sweden)

    S. R. Mukai

    2012-12-01

    Full Text Available Carbon gels are unique porous carbons, which aretypically obtained through the carbonization ofresorcinol-formaldehyde gels. This material ispractically an aggregate of nanometer-sized carbonparticles. Nanopores, mostly in the size range ofmesopores, exist between the particles. Smallerpores, micropores being the majority, also exist withinthe particles. Therefore, this material has ahierarchical pore system in which short microporesare directly connected to mesopores.The precursor of carbon gels can be obtained throughsol-gel transition. Therefore there is a high possibilitythat the morphology of the resulting carbon can beeasily controlled using various molding methods.We have actually challenged the controlling of themorphology of carbon gels, and have succeeded inobtaining them in the form of disks, microspheresand microhoneycombs. Details of such carbon gelswill be reported.

  15. Spatial regulation and organization of DNA replication within the nucleus

    OpenAIRE

    2009-01-01

    Duplication of chromosomal DNA is a temporally and spatially regulated process. The timing of DNA replication initiation at various origins is highly coordinated; some origins fire early and others late during S phase. Moreover, inside the nuclei, the bulk of DNA replication is physically organized in replication factories, consisting of DNA polymerases and other replication proteins. In this review article, we discuss how DNA replication is organized and regulated spatially within the nucleu...

  16. Replication of biotinylated human immunodeficiency viruses.

    Science.gov (United States)

    Belshan, Michael; Matthews, John M; Madson, Christian J

    2011-01-01

    Previous work demonstrated recently the adaptation of the Escherichia coli biotin ligase BirA - biotin acceptor sequence (BAS) labeling system to produce human immunodeficiency virus type 1 viruses with biotinylated integrase (NLXIN(B)) and matrix (NLXMA(B)) proteins (Belshan et al., 2009). This report describes the construction of an HIV permissive cell line stably expressing BirA (SupT1.BirA). Consistent with the results in the previous report, NLXMA(B) replicated similar to wild-type levels and expressed biotinylated Gag and MA proteins in the SupT1.BirA cells, whereas the replication of NLXIN(B) was reduced severely. Three additional HIV type 2 (HIV-2) viruses were constructed with the BAS inserted into the vpx and vpr accessory genes. Two BAS insertions were made into the C-terminal half of the Vpx, including one internal insertion, and one at the N-terminus of Vpr. All three viruses were replication competent in the SupT1.BirA cells and their target proteins biotinylated efficiently and incorporated into virions. These results demonstrate the potential utility of the biotinylation system to label and capture HIV protein complexes in the context of replicating virus.

  17. Chemistry: Small molecular replicators go organic

    Science.gov (United States)

    Taylor, Annette F.

    2016-09-01

    The emergence of complex, dynamic molecular behaviour might have had a role in the origin of life. Such behaviour has now been seen in a reaction network involving small, organic, self-replicating molecules of biological relevance. See Letter p.656

  18. Surface Micro Topography Replication in Injection Moulding

    DEFF Research Database (Denmark)

    Arlø, Uffe Rolf; Hansen, Hans Nørgaard; Kjær, Erik Michael

    2005-01-01

    The surface micro topography of injection moulded plastic parts can be important for aesthetical and technical reasons. The quality of replication of mould surface topography onto the plastic surface depends among other factors on the process conditions. A study of this relationship has been...

  19. The replication of expansive production knowledge

    DEFF Research Database (Denmark)

    Wæhrens, Brian Vejrum; Yang, Cheng; Madsen, Erik Skov

    2012-01-01

    exploration, the small sample size is an obvious limitation for generalisation. Practical implications – A roadmap for knowledge transfer within the replication of a production line is suggested, which, together with four managerial suggestions, provides strong support and clear directions to managers...

  20. Replication and Inhibitors of Enteroviruses and Parechoviruses

    Directory of Open Access Journals (Sweden)

    Lonneke van der Linden

    2015-08-01

    Full Text Available The Enterovirus (EV and Parechovirus genera of the picornavirus family include many important human pathogens, including poliovirus, rhinovirus, EV-A71, EV-D68, and human parechoviruses (HPeV. They cause a wide variety of diseases, ranging from a simple common cold to life-threatening diseases such as encephalitis and myocarditis. At the moment, no antiviral therapy is available against these viruses and it is not feasible to develop vaccines against all EVs and HPeVs due to the great number of serotypes. Therefore, a lot of effort is being invested in the development of antiviral drugs. Both viral proteins and host proteins essential for virus replication can be used as targets for virus inhibitors. As such, a good understanding of the complex process of virus replication is pivotal in the design of antiviral strategies goes hand in hand with a good understanding of the complex process of virus replication. In this review, we will give an overview of the current state of knowledge of EV and HPeV replication and how this can be inhibited by small-molecule inhibitors.