Identification and verification of hybridoma-derived monoclonal antibody variable region sequences using recombinant DNA technology and mass spectrometry.

Science.gov (United States)

Babrak, Lmar; McGarvey, Jeffery A; Stanker, Larry H; Hnasko, Robert

2017-10-01

Antibody engineering requires the identification of antigen binding domains or variable regions (VR) unique to each antibody. It is the VR that define the unique antigen binding properties and proper sequence identification is essential for functional evaluation and performance of recombinant antibodies (rAb). This determination can be achieved by sequence analysis of immunoglobulin (Ig) transcripts obtained from a monoclonal antibody (MAb) producing hybridoma and subsequent expression of a rAb. However the polyploidy nature of a hybridoma cell often results in the added expression of aberrant immunoglobulin-like transcripts or even production of anomalous antibodies which can confound production of rAb. An incorrect VR sequence will result in a non-functional rAb and de novo assembly of Ig primary structure without a sequence map is challenging. To address these problems, we have developed a methodology which combines: 1) selective PCR amplification of VR from both the heavy and light chain IgG from hybridoma, 2) molecular cloning and DNA sequence analysis and 3) tandem mass spectrometry (MS/MS) on enzyme digests obtained from the purified IgG. Peptide analysis proceeds by evaluating coverage of the predicted primary protein sequence provided by the initial DNA maps for the VR. This methodology serves to both identify and verify the primary structure of the MAb VR for production as rAb. Published by Elsevier Ltd.

Production of monoclonal antibody against Salmonella typhimurium by hybridoma technique

International Nuclear Information System (INIS)

Hasibuan, Adria P M; Sadi, Suharni

1998-01-01

In this research S.typhimurium killed by irradiation was used as antigen was prepared by exposing the bacteria to gamma rays from 60 Cobalt source with the dose of 2.5 kGy, Specific lymphocyte cell were obtained by immunizing 3 months old Balb-C mice with the antigen. the immunizations were done by subcutan route with the interval of 2 weeks. The hybridoma cells were made by fussing the specific lymphocyte cells with the myeloma cells. It was found that the animals (immunization + irradiation with a low dose of I Gy ) yielded monoclonal antibody with higher value (5.15 mg/ml) than the control animals (3.25 mg/ml). (author)

Reliable cloning of functional antibody variable domains from hybridomas and spleen cell repertoires employing a reengineered phage display system.

Science.gov (United States)

Krebber, A; Bornhauser, S; Burmester, J; Honegger, A; Willuda, J; Bosshard, H R; Plückthun, A

1997-02-14

A prerequisite for the use of recombinant antibody technologies starting from hybridomas or immune repertoires is the reliable cloning of functional immunoglobulin genes. For this purpose, a standard phage display system was optimized for robustness, vector stability, tight control of scFv-delta geneIII expression, primer usage for PCR amplification of variable region genes, scFv assembly strategy and subsequent directional cloning using a single rare cutting restriction enzyme. This integrated cloning, screening and selection system allowed us to rapidly obtain antigen binding scFvs derived from spleen-cell repertoires of mice immunized with ampicillin as well as from all hybridoma cell lines tested to date. As representative examples, cloning of monoclonal antibodies against a his tag, leucine zippers, the tumor marker EGP-2 and the insecticide DDT is presented. Several hybridomas whose genes could not be cloned in previous experimental setups, but were successfully obtained with the present system, expressed high amounts of aberrant heavy and light chain mRNAs, which were amplified by PCR and greatly exceeded the amount of binding antibody sequences. These contaminating variable region genes were successfully eliminated by employing the optimized phage display system, thus avoiding time consuming sequencing of non-binding scFv genes. To maximize soluble expression of functional scFvs subsequent to cloning, a compatible vector series to simplify modification, detection, multimerization and rapid purification of recombinant antibody fragments was constructed.

Homologous recombination in hybridoma cells: heavy chain chimeric antibody produced by gene targeting.

OpenAIRE

Fell, H P; Yarnold, S; Hellström, I; Hellström, K E; Folger, K R

1989-01-01

We demonstrate that murine myeloma cells can efficiently mediate homologous recombination. The murine myeloma cell line J558L was shown to appropriately recombine two transfected DNA molecules in approximately 30% of cells that received and integrated intact copies of both molecules. This activity was then exploited to direct major reconstructions of an endogenous locus within a hybridoma cell line. Production of antigen-specific chimeric heavy chain was achieved by targeting the human IgG1 h...

A fast and simple dot-immunobinding assay for quantifiction of mouse immunoglobulins in hybridoma culture supernatants

Czech Academy of Sciences Publication Activity Database

Sulimenko, Tetyana; Dráber, Pavel

2004-01-01

Roč. 289, - (2004), s. 89-95 ISSN 0022-1759 R&D Projects: GA AV ČR IBS5052301; GA MŠk LN00A026; GA MŠk 1P04OE158 Keywords : dot-immunobinding assay * hybridoma culture superntatants * mouse immunoglobulins Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.464, year: 2004

Viability and proliferation of L929, tumour and hybridoma cells in the culture media containing sericin protein as a supplement or serum substitute.

Science.gov (United States)

Cao, Ting-Ting; Zhang, Yu-Qing

2015-09-01

Cell cultures often require the addition of animal serum and other supplements. In this study, silk sericin, a bioactive protein, recovered from the waste of silk floss production was hydrolysed into three pepsin-degraded sericin peptides with different ranges of molecular mass. Normal animal cells, tumour cells and hybridoma cells were cultured systematically in FBS culture media containing sericin as a supplement or serum substitute. The culture test and microscopic observation of L929 cells showed that the smaller molecular weight of the degraded sericin is most suitable for cell culture. The cell culture results showed that with the degradation of sericin, for normal mouse fibroblast L929 cells, addition of 0.75 % sericin into FBS culture medium yields cell viability that is superior to FBS culture medium alone. When all serum was replaced by sericin, cell viability in the sericin medium could reach about one half of that in FBS medium. When in a medium containing a mixture of FBS: sericin (6:4, v/v), the cell culture effect is about 80 %. For the cultures of four tumour and one hybridoma cells, regardless of the molecular weight range, these degraded sericin peptides could substitute all serum in FBS media. The cell viability and proliferation of these tumour and hybridoma cells are equivalent or superior to that in FBS medium. In other words, cell viability and proliferation of these tumour and hybridoma cells in sericin media are more preferable to serum media. The mechanism of the sericin protein to promote cell growth and proliferation will be further investigated later.

Growth and production kinetics of human x mouse and mouse hybridoma cells at reduced temperature and serum content.

Science.gov (United States)

Borth, N; Heider, R; Assadian, A; Katinger, H

1992-09-01

The growth and production kinetics of a mouse hybridoma cell line and a human-mouse heterohybridoma were analyzed under conditions of reduced temperature and serum content. The mouse hybridoma P24 had a constant cell specific production rate and RNA content, while the heterohybridoma 3D6-LC4 showed growth associated production kinetics and an increased RNA content at higher growth rates. This behaviour of 3D6-LC4 cells can be explained by the unusual cell cycle kinetics of this line, which can be arrested in any phase under growth limiting conditions, so that a low growth rate does not result in a greater portion of high producing G1-phase cells. Substrate limitation changes the cell cycle distribution of this cell line to a greater extent than low temperature or serum content, which indicates that this stress factor exerts a greater physiological control than assumed.

Inhibition of mannosidase in hybridomas yields monoclonal antibodies with greater capacity for carbohydrate labeling

International Nuclear Information System (INIS)

Simonson, R.B.; Ultee, M.E.; Long, C.G.; Gillette, R.W.; McKearn, T.J.; Rodwell, J.D.

1988-01-01

Labeling an antibody site specifically through its carbohydrate residues preserves more of its antigen-binding activity than does labeling through protein moieties. To boost the amount of immunoglobulin G carbohydrate capable of being labeled, we treated hybridoma cells with a mannosidase inhibitor, deoxymannojirimycin (dMM). Polyacrylamide gel electrophoresis showed formation of a glycoprotein with high mannose content, in that endo-beta-N-acetylglucosaminidase H 3.2.1.96) could digest the antibody from the dMM-treated cells, but not from control cultures. Carbohydrate analysis confirmed this conclusion, indicating that the antibody from the dMM-treated cells had twice as much mannose as did the control antibody. The glucosamine content of the treated-cells' antibodies was half that of the control, and no additional carbohydrate residues were detectable in the antibodies secreted by the dMM-treated cells. We conjugated both the dMM and control antibodies through their carbohydrate to a chelator. In labeling, the dMM antibody conjugate incorporated approximately threefold as much 111 In isotope as the control conjugate. The two labeled antibodies were injected into mice and showed similar organ distributions

CELLISA: reporter cell-based immunization and screening of hybridomas specific for cell surface antigens.

Science.gov (United States)

Chen, Peter; Mesci, Aruz; Carlyle, James R

2011-01-01

Monoclonal antibodies (mAbs) specific for cell surface antigens are an invaluable tool to study immune receptor expression and function. Here, we outline a generalized reporter cell-based approach to the generation and high-throughput screening of mAbs specific for cell surface antigens. Termed CELLISA, this technology hinges upon the capture of hybridoma supernatants in mAb arrays that facilitate ligation of an antigen of interest displayed on BWZ reporter cells in the form of a CD3ζ-fusion chimeric antigen receptor (zCAR); in turn, specific mAb-mediated cross-linking of zCAR on BWZ cells results in the production of β-galactosidase enzyme (β-gal), which can be assayed colorimetrically. Importantly, the BWZ reporter cells bearing the zCAR of interest may be used for immunization as well as screening. In addition, serial immunizations employing additional zCAR- or native antigen-bearing cell lines can be used to increase the frequency of the desired antigen-specific hybridomas. Finally, the use of a cohort of epitope-tagged zCAR (e.g., zCAR(FLAG)) variants allows visualization of the cell surface antigen prior to immunization, and coimmunization using these variants can be used to enhance the immunogenicity of the target antigen. Employing the CELLISA strategy, we herein describe the generation of mAb directed against an uncharacterized natural killer cell receptor protein.

Screening individual hybridomas by microengraving to discover monoclonal antibodies

Science.gov (United States)

Ogunniyi, Adebola O; Story, Craig M; Papa, Eliseo; Guillen, Eduardo; Love, J Christopher

2014-01-01

The demand for monoclonal antibodies (mAbs) in biomedical research is significant, but the current methodologies used to discover them are both lengthy and costly. Consequently, the diversity of antibodies available for any particular antigen remains limited. Microengraving is a soft lithographic technique that provides a rapid and efficient alternative for discovering new mAbs. This protocol describes how to use microengraving to screen mouse hybridomas to establish new cell lines producing unique mAbs. Single cells from a polyclonal population are isolated into an array of microscale wells (~105 cells per screen). The array is then used to print a protein microarray, where each element contains the antibodies captured from individual wells. The antibodies on the microarray are screened with antigens of interest, and mapped to the corresponding cells, which are then recovered from their microwells by micromanipulation. Screening and retrieval require approximately 1–3 d (9–12 d including the steps for preparing arrays of microwells). PMID:19528952

Retention of CXCR4 in the endoplasmic reticulum blocks dissemination of a T cell hybridoma.

Science.gov (United States)

Zeelenberg, I S; Ruuls-Van Stalle, L; Roos, E

2001-07-01

The dissemination of T cell hybridomas to multiple nonhematopoietic tissues is blocked by pertussis toxin, suggesting the involvement of a chemokine. To study whether this chemokine is SDF-1, we employed a strategy proposed previously for gene therapy of AIDS, whereby the SDF-1 receptor CXCR4 (also a coreceptor for HIV) is retained in the endoplasmic reticulum (ER) and fails to reach the cell surface. We transfected SDF-1, carrying an ER retention sequence, into a T cell hybridoma. This altered chemokine is retained in the ER, where it binds CXCR4 and prevents the latter protein from reaching the surface. These cells failed to migrate toward SDF-1 or to invade fibroblast monolayers, although they could still migrate toward thymus and activation-regulated chemokine (TARC) and invade TARC-treated monolayers. Furthermore, the ability of the transfected cells to disseminate to multiple organs upon intravenous injection into mice was abolished. This dissemination reflects the in vivo migration patterns of activated and memory T cells into nonhematopoietic tissues, which is thus likely to depend on CXCR4. Attempts to block CXCR4 function as a therapy for AIDS may affect this migration with consequences for T cell function. Our results also suggest a decisive role for CXCR4 in the dissemination of hematopoietic malignancies expressing this receptor.

Complete dissection of the Hb(64-76) determinant using T helper 1, T helper 2 clones, and T cell hybridomas

DEFF Research Database (Denmark)

Evavold, B D; Williams, S G; Hsu, B L

1992-01-01

We have generated cloned Th1 cells, Th2 cells, and T cell hybridomas specific for the single immunogenic peptide from the beta-chain of murine hemoglobin (Hb(64-76)). The availability of these various types of T cells provided us an unique opportunity to examine and dissect the T cell response...... to an immunogenic peptide. A panel of altered Hb peptides was made by replacing each amino acid in the Hb peptide (positions 64-76) with a conservative amino acid substitution or an alanine. Although none of the eleven T cell clones and hybridomas tested exhibited the same pattern of reactivity to the substituted...... Hb peptides, some general features were identified for all T cell responses. The primary T cell contact residue of Hb(64-76) was shown to be asparagine 72. For every Hb(64-76) specific T cell, no activation was observed using a peptide containing the conservative substitution of a glutamine...

High-throughput screening of hybridoma supernatants using multiplexed fluorescent cell barcoding on live cells.

Science.gov (United States)

Lu, Mei; Chan, Brian M; Schow, Peter W; Chang, Wesley S; King, Chadwick T

2017-12-01

With current available assay formats using either immobilized protein (ELISA, enzyme-linked immunosorbent assay) or immunostaining of fixed cells for primary monoclonal antibody (mAb) screening, researchers often fail to identify and characterize antibodies that recognize the native conformation of cell-surface antigens. Therefore, screening using live cells has become an integral and important step contributing to the successful identification of therapeutic antibody candidates. Thus the need for developing high-throughput screening (HTS) technologies using live cells has become a major priority for therapeutic mAb discovery and development. We have developed a novel technique called Multiplexed Fluorescent Cell Barcoding (MFCB), a flow cytometry-based method based upon the Fluorescent Cell Barcoding (FCB) technique and the Luminex fluorescent bead array system, but is applicable to high-through mAb screens on live cells. Using this technique in our system, we can simultaneously identify or characterize the antibody-antigen binding of up to nine unique fluorescent labeled cell populations in the time that it would normally take to process a single population. This has significantly reduced the amount of time needed for the identification of potential lead candidates. This new technology enables investigators to conduct large-scale primary hybridoma screens using flow cytometry. This in turn has allowed us to screen antibodies more efficiently than before and streamline identification and characterization of lead molecules. Copyright © 2017 Elsevier B.V. All rights reserved.

Design and Generation of Humanized Single-chain Fv Derived from Mouse Hybridoma for Potential Targeting Application.

Science.gov (United States)

Khantasup, Kannika; Chantima, Warangkana; Sangma, Chak; Poomputsa, Kanokwan; Dharakul, Tararaj

2015-12-01

Single-chain variable antibody fragments (scFvs) are attractive candidates for targeted immunotherapy in several human diseases. In this study, a concise humanization strategy combined with an optimized production method for humanizing scFvs was successfully employed. Two antibody clones, one directed against the hemagglutinin of H5N1 influenza virus, the other against EpCAM, a cancer biomarker, were used to demonstrate the validity of the method. Heavy chain (VH) and light chain (VL) variable regions of immunoglobulin genes from mouse hybridoma cells were sequenced and subjected to the construction of mouse scFv 3-D structure. Based on in silico modeling, the humanized version of the scFv was designed via complementarity-determining region (CDR) grafting with the retention of mouse framework region (FR) residues identified by primary sequence analysis. Root-mean-square deviation (RMSD) value between mouse and humanized scFv structures was calculated to evaluate the preservation of CDR conformation. Mouse and humanized scFv genes were then constructed and expressed in Escherichia coli. Using this method, we successfully generated humanized scFvs that retained the targeting activity of their respective mouse scFv counterparts. In addition, the humanized scFvs were engineered with a C-terminal cysteine residue (hscFv-C) for site-directed conjugation for use in future targeting applications. The hscFv-C expression was extensively optimized to improve protein production yield. The protocol yielded a 20-fold increase in production of hscFv-Cs in E. coli periplasm. The strategy described in this study may be applicable in the humanization of other antibodies derived from mouse hybridoma.

Enzyme immunoassay for rabies antibody in hybridoma culture fluids and its application to differentiation of street and laboratory strains of rabies virus.

OpenAIRE

Smith, J S; Sumner, J W; Roumillat, L F

1984-01-01

A rapid and sensitive enzyme immunoassay is described for detecting rabies antibody in hybridoma culture fluids. Glass fiber filter disks were used to immobilize gamma-irradiated mouse neuroblastoma cells infected with street or laboratory strains of rabies virus. Bound rabies-specific antibody was detected by reaction with horseradish peroxidase-labeled goat anti-mouse immunoglobulin G. The assay was performed in a 96-well filtration device developed by Cleveland et al. (J. Clin. Microbiol. ...

From hybridomas to a robust microalgal-based production platform: molecular design of a diatom secreting monoclonal antibodies directed against the Marburg virus nucleoprotein.

Science.gov (United States)

Hempel, Franziska; Maurer, Michael; Brockmann, Björn; Mayer, Christian; Biedenkopf, Nadine; Kelterbaum, Anne; Becker, Stephan; Maier, Uwe G

2017-07-27

The ideal protein expression system should provide recombinant proteins in high quality and quantity involving low production costs only. However, especially for complex therapeutic proteins like monoclonal antibodies many challenges remain to meet this goal and up to now production of monoclonal antibodies is very costly and delicate. Particularly, emerging disease outbreaks like Ebola virus in Western Africa in 2014-2016 make it necessary to reevaluate existing production platforms and develop robust and cheap alternatives that are easy to handle. In this study, we engineered the microalga Phaeodactylum tricornutum to produce monoclonal IgG antibodies against the nucleoprotein of Marburg virus, a close relative of Ebola virus causing severe hemorrhagic fever with high fatality rates in humans. Sequences for both chains of a mouse IgG antibody were retrieved from a murine hybridoma cell line and implemented in the microalgal system. Fully assembled antibodies were shown to be secreted by the alga and antibodies were proven to be functional in western blot, ELISA as well as IFA studies just like the original hybridoma produced IgG. Furthermore, synthetic variants with constant regions of a rabbit IgG and human IgG with optimized codon usage were produced and characterized. This study highlights the potential of microalgae as robust and low cost expression platform for monoclonal antibodies secreting IgG antibodies directly into the culture medium. Microalgae possess rapid growth rates, need basically only water, air and sunlight for cultivation and are very easy to handle.

Establishment and characterization of mouse bone marrow-derived mast cell hybridomas

International Nuclear Information System (INIS)

Kawahara, Takeshi

2012-01-01

Interleukin (IL)-3-dependent mouse bone marrow-derived mast cells (BMMCs) are an important model for studying the function of mucosal-type mast cells. In the present study, BMMCs were successfully immortalized by cell fusion using a hypoxanthine–aminopterin–thymidine medium-sensitive variant of P815 mouse mastocytoma (P815-6TgR) as a partner cell line. The established mouse mast cell hybridomas (MMCHs) expressed α, β, and γ subunits of high-affinity immunoglobulin E (IgE) receptor (FcεRI) and possessed cytoplasmic granules devoid of or partially filled with electron-dense material. Four independent MMCH clones continuously proliferated without supplemental exogenous IL-3 and showed a degranulation response on stimulation with IgE+antigen. Furthermore, histamine synthesis and release by degranulation were confirmed in MMCH-D5, a MMCH clone that showed the strongest degranulation response. MMCH-D5 exhibited elevated levels of IL-3, IL-4, IL-13, granulocyte-macrophage colony-stimulating factor, tumor necrosis factor (TNF)-α, and cyclooxygenase 2, and production of prostaglandin D 2 and leukotriene C 4 in response to IgE-induced stimulation. MMCH clones also expressed Toll-like receptors (TLRs) 1, 2, 4, and 6 and showed elevated levels of TNF-α expression in response to stimulation with TLR2 and TLR4 ligands. The MMCHs established using this method should be suitable for studies on FcεRI- and TLR-mediated effector functions of mast cells.

Establishment and characterization of mouse bone marrow-derived mast cell hybridomas

Energy Technology Data Exchange (ETDEWEB)

Kawahara, Takeshi, E-mail: tkawafb@shinshu-u.ac.jp [Integrated Department of Sciences of Functional Foods, Graduate School of Agriculture, Shinshu University, Nagano (Japan)

2012-11-01

Interleukin (IL)-3-dependent mouse bone marrow-derived mast cells (BMMCs) are an important model for studying the function of mucosal-type mast cells. In the present study, BMMCs were successfully immortalized by cell fusion using a hypoxanthine-aminopterin-thymidine medium-sensitive variant of P815 mouse mastocytoma (P815-6TgR) as a partner cell line. The established mouse mast cell hybridomas (MMCHs) expressed {alpha}, {beta}, and {gamma} subunits of high-affinity immunoglobulin E (IgE) receptor (Fc{epsilon}RI) and possessed cytoplasmic granules devoid of or partially filled with electron-dense material. Four independent MMCH clones continuously proliferated without supplemental exogenous IL-3 and showed a degranulation response on stimulation with IgE+antigen. Furthermore, histamine synthesis and release by degranulation were confirmed in MMCH-D5, a MMCH clone that showed the strongest degranulation response. MMCH-D5 exhibited elevated levels of IL-3, IL-4, IL-13, granulocyte-macrophage colony-stimulating factor, tumor necrosis factor (TNF)-{alpha}, and cyclooxygenase 2, and production of prostaglandin D{sub 2} and leukotriene C{sub 4} in response to IgE-induced stimulation. MMCH clones also expressed Toll-like receptors (TLRs) 1, 2, 4, and 6 and showed elevated levels of TNF-{alpha} expression in response to stimulation with TLR2 and TLR4 ligands. The MMCHs established using this method should be suitable for studies on Fc{epsilon}RI- and TLR-mediated effector functions of mast cells.

Design and performance of a trickle-bed bioreactor with immobilized hybridoma cells.

Science.gov (United States)

Phillips, H A; Scharer, J M; Bols, N C; Moo-Young, M

1992-01-01

A trickle-bed system employing inert matrices of vermiculite or polyurethane foam packed in the downcomer section of a split-flow air-lift reactor has been developed for hybridoma culture to enhance antibody productivity. This quiescent condition favoured occlusion and allowed the cells to achieve densities twelve fold greater (12.8 x 10(6) cells/ml reactor for polyurethane foam) than in free cell suspension. The reactor was operated in a cyclic batch mode whereby defined volumes of medium were periodically withdrawn and replaced with equal volumes of fresh medium. The pH of the medium was used as the indicator of the feeding schedule. Glucose, lactate and ammonia concentrations reached a stationary value after 5 days. With vermiculite packing, a monoclonal antibody (MAb) concentration of 2.4 mg/l was achieved after 12 days. The MAb concentration declined then increased to a value of 1.8 mg/l. In the polyurethane foam average monoclonal antibody (MAb) concentrations reached a stationary value of 1.1 mg/l in the first 20 days and increased to a new stationary state value of 2.1 mg/l for the remainder of the production. MAb productivity in the trickle-bed reactor was 0.3 mg/l.d (polyurethane foam) and 0.18 mg/l.d (vermiculite) in comparison to 0.12 mg/l.d for free cell suspension. This trickle-bed system seems to be an attractive way of increasing MAb productivity in culture.

Optimization of monoclonal antibody production in mouse ascites by single whole-body irradiation

International Nuclear Information System (INIS)

Witt, S.; Ziegler, B.; Kloeting, I.; Ziegler, M.; Nadrowitz, R.; Schmidt, W.

1987-01-01

Hybridoma cells injected intraperitoneally into mice induce formation of ascites tumors producing ascites fluid with high levels of monoclonal antibodies. Several parameters affect the growth of the immunoglobulin-producing tumors in vivo. In 10 different hybridomas the average ascites tumor formation rate could be increased from 32% (n = 338 mice) to 77% (n = 112 mice) by only one whole-body irradiation of paraffin-pretreated Balb/c mice. Production of monoclonal antibodies was better in males because of the significantly (p < 0.01) increased volume of ascites fluid. From the increased tumor formation rate in irradiated mice it is suggested that in non-irradiated recipients the tumor growth rate was lowered by immunological reactions against hybridoma cells provoked by cell surface neoantigens revealed by cell fusion and/or tumor-associated antigens of the myeloma parent cells as well as by altered antigen pattern caused by possible mutations in the myeloma cell line and/or Balb/c/K strain. (author)

Co-ordinated research program on development of kits for radioimmunometric assays of tumor markers

International Nuclear Information System (INIS)

Acevedo Castro, B.E.; Perera Negrin, Y.; Pichardo Diaz, D.; Murugiah, R.; Ayala Avila, M.; Gavilondo Cowley, J.; Ruiz Pena, M.; Caso Pena, R.; Hernandez Pagarizabal, M.

1999-01-01

Mice were immunized with semen and natural PSA, following three different schemes. Splenocytes from two hyper immune animals were fused with the P3/x63.Ag8.653 myeloma under conventional hybridoma procedures. Stable hybrid cell cultures secreting antibodies specific to natural PSA were obtained by cloning dilutions procedures. With a group of stable hybridoma cultures we developed epitope characterization assays to determine whether the antibodies were capable of recognizing PSA. According to the recognition level in ELISA, the hybridomas were classified in different groups,. We select the best pairs of Mabs for developing a total and free PSA assays based on ELISA or IRMA format. Our total-PSA based on IRMA format presented a good correlation in comparison with CIS bio total PSA assay. We recommend our anti-PSA monoclonal antibodies to develop an IRMA assay for total PSA. Cuban free-PSA assay is under evaluation at present. (author)

Effect of amino acid supplementation on titer and glycosylation distribution in hybridoma cell cultures-Systems biology-based interpretation using genome-scale metabolic flux balance model and multivariate data analysis.

Science.gov (United States)

Reimonn, Thomas M; Park, Seo-Young; Agarabi, Cyrus D; Brorson, Kurt A; Yoon, Seongkyu

2016-09-01

Genome-scale flux balance analysis (FBA) is a powerful systems biology tool to characterize intracellular reaction fluxes during cell cultures. FBA estimates intracellular reaction rates by optimizing an objective function, subject to the constraints of a metabolic model and media uptake/excretion rates. A dynamic extension to FBA, dynamic flux balance analysis (DFBA), can calculate intracellular reaction fluxes as they change during cell cultures. In a previous study by Read et al. (2013), a series of informed amino acid supplementation experiments were performed on twelve parallel murine hybridoma cell cultures, and this data was leveraged for further analysis (Read et al., Biotechnol Prog. 2013;29:745-753). In order to understand the effects of media changes on the model murine hybridoma cell line, a systems biology approach is applied in the current study. Dynamic flux balance analysis was performed using a genome-scale mouse metabolic model, and multivariate data analysis was used for interpretation. The calculated reaction fluxes were examined using partial least squares and partial least squares discriminant analysis. The results indicate media supplementation increases product yield because it raises nutrient levels extending the growth phase, and the increased cell density allows for greater culture performance. At the same time, the directed supplementation does not change the overall metabolism of the cells. This supports the conclusion that product quality, as measured by glycoform assays, remains unchanged because the metabolism remains in a similar state. Additionally, the DFBA shows that metabolic state varies more at the beginning of the culture but less by the middle of the growth phase, possibly due to stress on the cells during inoculation. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1163-1173, 2016. © 2016 American Institute of Chemical Engineers.

Combined data preprocessing and multivariate statistical analysis characterizes fed-batch culture of mouse hybridoma cells for rational medium design.

Science.gov (United States)

Selvarasu, Suresh; Kim, Do Yun; Karimi, Iftekhar A; Lee, Dong-Yup

2010-10-01

We present an integrated framework for characterizing fed-batch cultures of mouse hybridoma cells producing monoclonal antibody (mAb). This framework systematically combines data preprocessing, elemental balancing and statistical analysis technique. Initially, specific rates of cell growth, glucose/amino acid consumptions and mAb/metabolite productions were calculated via curve fitting using logistic equations, with subsequent elemental balancing of the preprocessed data indicating the presence of experimental measurement errors. Multivariate statistical analysis was then employed to understand physiological characteristics of the cellular system. The results from principal component analysis (PCA) revealed three major clusters of amino acids with similar trends in their consumption profiles: (i) arginine, threonine and serine, (ii) glycine, tyrosine, phenylalanine, methionine, histidine and asparagine, and (iii) lysine, valine and isoleucine. Further analysis using partial least square (PLS) regression identified key amino acids which were positively or negatively correlated with the cell growth, mAb production and the generation of lactate and ammonia. Based on these results, the optimal concentrations of key amino acids in the feed medium can be inferred, potentially leading to an increase in cell viability and productivity, as well as a decrease in toxic waste production. The study demonstrated how the current methodological framework using multivariate statistical analysis techniques can serve as a potential tool for deriving rational medium design strategies. Copyright © 2010 Elsevier B.V. All rights reserved.

Investigation of intratumoural and peritumoural lymphatics expressed by podoplanin and LYVE-1 in the hybridoma-induced tumours

Science.gov (United States)

Ji, RC; Eshita, Y; Kato, S

2007-01-01

Tumour-associated lymphatics contribute to a key component of metastatic spread, however, the biological interaction of tumour cells with intratumoural and peritumoural lymphatics (ITLs and PTLs) has remained unclear. To address this important issue, we have focused on the morphological and molecular aspects of newly formed lymphatics (lymphangiogenesis) and pre-existing lymphatics in the intratumoural and peritumoural tissues by using a hybridoma-induced tumour model. In the present study, ITLs with very high vessel density within the tumour mass showed small and flattened contours that varied from non-solid-to-solid tumours, whereas PTLs were relatively disorganized and tortuous, and packed with a cluster of tumour cells at the tumour periphery. Lymphatic endothelial cells (LECs) both in ITLs and PTLs were expressed with LYVE-1 and podoplanin in various tumour tissues, in which initial lymphatics were extremely extended and dilated. The tumour cells were frequently detected adhering to or penetrating lymphatic walls, especially near the open junctions. In the metastatic tissues, lymphangiogenic vasculatures occurred within the tumour matrix, and collecting PTLs represented abnormal twisty valve leaflets. The Western blot and RT-PCR analysis showed local variations of LEC proliferating potentials and lymphatic involvement in metastasis by a distinct profile of the protein and mRNA expression by LYVE-1, podoplanin, Prox-1 and vascular endothelial growth factor-3 (VEGFR-3). These findings indicated that both ITLs and PTLs, including enlarged pre-existing and newly formed lymphatics, may play a crucial role in metastasis with an active tumour cell adhesion, invasion, migration and implantation. PMID:17696907

On-line monitoring of monoclonal antibody formation in high density perfusion culture using FIA.

Science.gov (United States)

Fenge, C; Fraune, E; Freitag, R; Scheper, T; Schügerl, K

1991-05-01

An automated flow injection system for on-line analysis of proteins in real fermentation fluids was developed by combining the principles of stopped-flow, merging zones flow injection analysis (FIA) with antigen-antibody reactions. IgG in the sample reacted with its corresponding antibody (a-IgG) in the reagent solution. Formation of insoluble immunocomplexes resulted in an increase of the turbidity which was determined photometrically. This system was used to monitor monoclonal antibody production in high cell density perfusion culture of hybridoma cells. Perfusion was performed with a newly developed static filtration unit equipped with hydrophilic microporous tubular membranes. Different sampling devices were tested to obtain a cell-free sample stream for on-line product analysis of high molecular weight (e.g., monoclonal antibodies) and low molecular weight (e.g., glucose, lactate) medium components. In fermentation fluids a good correlation (coefficient: 0.996) between the FIA method and an ELISA test was demonstrated. In a high density perfusion cultivation process mAb formation was successfully monitored on-line over a period of 400 h using a reliable sampling system. Glucose and lactate were measured over the same period of time using a commercially available automatic analyser based on immobilized enzyme technology.

A perfusion culture system using a stirred ceramic membrane reactor for hyperproduction of IgG2a monoclonal antibody by hybridoma cells.

Science.gov (United States)

Dong, Haodi; Tang, Ya-Jie; Ohashi, Ryo; Hamel, Jean-François P

2005-01-01

A novel perfusion culture system for efficient production of IgG2a monoclonal antibody (mAb) by hybridoma cells was developed. A ceramic membrane module was constructed and used as a cell retention device installed in a conventional stirred-tank reactor during the perfusion culture. Furthermore, the significance of the control strategy of perfusion rate (volume of fresh medium/working volume of reactor/day, vvd) was investigated. With the highest increasing rate (deltaD, vvd per day, vvdd) of perfusion rate, the maximal viable cell density of 3.5 x 10(7) cells/mL was obtained within 6 days without any limitation and the cell viability was maintained above 95%. At lower deltaD's, the cell growth became limited. Under nutrient-limited condition, the specific cell growth rate (mu) was regulated by deltaD. During the nonlimited growth phase, the specific mAb production rate (qmAb) remained constant at 0.26 +/- 0.02 pg/cell x h in all runs. During the cell growth-limited phase, qmAb was regulated by deltaD within the range of 0.25-0.65 vvdd. Under optimal conditions, qmAb of 0.80 and 2.15 pg/cell x h was obtained during the growth-limited phase and stationary phase, respectively. The overall productivity and yield were 690 mg/L x day and 340 mg/L x medium, respectively. This study demonstrated that this novel perfusion culture system for suspension mammalian cells can support high cell density and efficient mAb production and that deltaD is an important control parameter to regulate and achieve high mAb production.

An immunoassay for dibutyl phthalate based on direct hapten linkage to the polystyrene surface of microtiter plates.

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Chenxi Wei

Full Text Available BACKGROUND: Dibutyl phthalate (DBP is predominantly used as a plasticizer inplastics to make them flexible. Extensive use of phthalates in both industrial processes and other consumer products has resulted in the ubiquitous presence of phthalates in the environment. In order to better determine the level of pollution in the environment and evaluate the potential adverse effects of exposure to DBP, immunoassay for DBP was developed. METHODOLOGY/PRINCIPAL FINDINGS: A monoclonal antibody specific to DBP was produced from a stable hybridoma cell line generated by lymphocyte hybridoma technique. An indirect competitive enzyme-linked immunosorbent assay (icELISA employing direct coating of hapten on polystyrene microtiter plates was established for the detection of DBP. Polystyrene surface was first oxidized by permanganate in dilute sulfuric acid to generate carboxyl groups. Then dibutyl 4-aminophthalate, which is an analogue of DBP, was covalently linked to the carboxyl groups of polystyrene surface with 1-ethyl-3-(3-dimethylaminopropyl carbodiimide hydrochloride (EDC. Compared with conjugate coated format (IC(50=106 ng/mL, the direct hapten coated format (IC(50=14.6 ng/mL improved assay sensitivity after careful optimization of assay conditions. The average recovery of DBP from spiked water sample was 104.4% and the average coefficient of variation was 9.95%. Good agreement of the results obtained by the hapten coated icELISA and gas chromatography-mass spectrometry further confirmed the reliability and accuracy of the icELISA for the detection of DBP in certain plastic and cosmetic samples. CONCLUSIONS/SIGNIFICANCE: The stable and efficient hybridoma cell line obtained is an unlimited source of sensitive and specific antibody to DBP. The hapten coated format is proposed as generally applicable because the carboxyl groups on modified microtiter plate surface enables stable immobilization of aminated or hydroxylated hapten with EDC. The developed

Multistep process of neoplastic transformation of normal human fibroblasts by 60Co gamma rays and Harvey sarcoma viruses

Energy Technology Data Exchange (ETDEWEB)

Namba, M.; Nishitani, K.; Fukushima, F.; Kimoto, T.; Nose, K.

1986-03-15

As reported previously (Namba et al., 1985), normal human fibroblasts were transformed by 60Co gamma-ray irradiation into immortal cells with abnormal karyotypes. These transformed cells (KMST-6), however, showed a low cloning efficiency in soft agar and no transplantability. However, upon treatment with Harvey murine sarcoma virus (Ha-MSV), the cells acquired elevated clonability in soft agar and transplantability in nude mice. Ha-MSV alone, however, did not convert normal human fibroblasts into either immortal or tumorigenic cells. The Ha-MSV-transformed KMST-6 cells showed an enhanced expression of the ras oncogene, but normal and 60Co gamma-ray-transformed cells did not. Our current data suggest that gamma rays worked against normal human cells as an initiator, giving rise to chromosome aberrations and immortality, and that Ha-MSV, probably through its ras oncogene, played a role in the progression of the malignant cell population to a more malignant one showing enhanced colony formation in soft agar and tumorigenicity in nude mice.

Characterization of sporozoite surface antigens of Plasmodium falciparum, using monoclonal antibodies. Part of a coordinated programme on the preparation of irradiated vaccines against some human diseases

International Nuclear Information System (INIS)

Groot, M.

1982-10-01

Sporozoites are considered as a source of potential vaccine. Characterization of their antigens is therefore important and can be achieved by monoclonal antibodies. The purpose of this project is to study the production of monoclonal antibodies against sporozoites of P. falciparum. Various infections of mosquitoes were carried out during the period 1981-1982 to obtain antigens for the production of hybridomas. Hybridomas were produced from mice immunized through the bites of infected mosquitoes and by intravenous inoculation. The anti-sporozoite activity of the hybridomas was tested by an immunofluorescent antibody test using P. falciparum sporozoites as antigens. Positive immunofluorescence was seen in hybridoma cell lines tested with P. falciparum, whereas negative results were obtained when the cell lines were cross-reacted with other human species (P. vivax) and with a rodent malaria parasite (P. berghei)

Antibodies and Selection of Monoclonal Antibodies.

Science.gov (United States)

Hanack, Katja; Messerschmidt, Katrin; Listek, Martin

Monoclonal antibodies are universal binding molecules with a high specificity for their target and are indispensable tools in research, diagnostics and therapy. The biotechnological generation of monoclonal antibodies was enabled by the hybridoma technology published in 1975 by Köhler and Milstein. Today monoclonal antibodies are used in a variety of applications as flow cytometry, magnetic cell sorting, immunoassays or therapeutic approaches. First step of the generation process is the immunization of the organism with appropriate antigen. After a positive immune response the spleen cells are isolated and fused with myeloma cells in order to generate stable, long-living antibody-producing cell lines - hybridoma cells. In the subsequent identification step the culture supernatants of all hybridoma cells are screened weekly for the production of the antibody of interest. Hybridoma cells producing the antibody of interest are cloned by limited dilution till a monoclonal hybridoma is found. This is a very time-consuming and laborious process and therefore different selection strategies were developed since 1975 in order to facilitate the generation of monoclonal antibodies. Apart from common automation of pipetting processes and ELISA testing there are some promising approaches to select the right monoclonal antibody very early in the process to reduce time and effort of the generation. In this chapter different selection strategies for antibody-producing hybridoma cells are presented and analysed regarding to their benefits compared to conventional limited dilution technology.

Production and characterisation of monoclonal antibodies against native and disassembled human catalase

NARCIS (Netherlands)

Wiemer, E. A.; Ofman, R.; Middelkoop, E.; de Boer, M.; Wanders, R. J.; Tager, J. M.

1992-01-01

Catalase isolated from human erythrocytes was used to immunise mice, in order to generate hybridomas producing specific monoclonal antibodies to the enzyme. Hybridomas secreting anti-(catalase) antibodies were identified by a modified enzyme-linked immunosorbent assay (ELISA) using either

Relativity, anomalies and objectivity loophole in recent tests of local realism

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Bednorz Adam

2017-11-01

Full Text Available Local realism is in conflict with special quantum Bell-type models. Recently, several experiments have demonstrated violation of local realism if we trust their setup assuming special relativity valid. In this paper we question the assumption of relativity, point out not commented anomalies and show that the experiments have not closed objectivity loophole because clonability of the result has not been demonstrated. We propose several improvements in further experimental tests of local realism make the violation more convincing.

A monoclonal antibody that specifically recognizes m6A nucleoside

OpenAIRE

Espuny, Ruth; Castro, Ana; Codony, Carles; Eritja Casadellà, Ramón; Bach-Elias, Montse

1998-01-01

A hybridoma against the nucleoside m6A has been obtained from mouse spleen. This hybridoma was named H65 and it secretes monoclonal antibodies anti-m6A. The competition assays showed that the monoclonal antibody was highly specific for m6A nucleoside.

Investigation of a panel of monoclonal antibodies and polyclonal sera against anthrax toxins resulted in identification of an anti-lethal factor antibody with disease-enhancing characteristics.

Science.gov (United States)

Kulshreshtha, Parul; Tiwari, Ashutosh; Priyanka; Joon, Shikha; Sinha, Subrata; Bhatnagar, Rakesh

2015-12-01

Hybridomas were created using spleen of mice that were actively immunized with rLFn (recombinant N-terminal domain of lethal factor). Later on, separate group of mice were immunized with rLFn to obtain a polyclonal control for passive immunization studies of monoclonal antibodies. This led to the identification of one cohort of rLFn-immnized mice that harboured disease-enhancing polyclonal antibodies. At the same time, the monoclonal antibodies secreted by all the hybridomas were being tested. Two hybridomas secreted monoclonal antibodies (H10 and H8) that were cross-reactive with EF (edema factor) and LF (lethal factor), while the other two hybridomas secreted LF-specific antibodies (H7 and H11). Single chain variable fragment (LETscFv) was derived from H10 hybridoma. H11 was found to have disease-enhancing property. Combination of H11 with protective monoclonal antibodies (H8 and H10) reduced its disease enhancing nature. This in vitro abrogation of disease-enhancement provides the proof of concept that in polyclonal sera the disease enhancing character of a fraction of antibodies is overshadowed by the protective nature of the rest of the antibodies generated on active immunization. Copyright © 2015. Published by Elsevier Ltd.

A new and rapid method for immunoglobulin class and subclass determination of mouse monoclonal antibodies using a solid-phase immunoradiometric assay

International Nuclear Information System (INIS)

Storch, M.-J.; Lohmann-Matthes, M.-L.

1984-01-01

A solid-phase immunoradiometric assay is described for the detection of mouse immunoglobulin classes and subclasses in unpurified and unconcentrated supernatants of hybridomas. IgG fractions from rabbit antisera specific for mouse immunoglobulin classes and subclasses are used for coating the wells of flexible microtiter plates. Monoclonal antibody present in hybridoma supernatants is bound only to wells that contain the appropriate anti-subclass antibody. The binding of hybridoma antibodies to corresponding IgG subclasses or IgM is then detected by a labeled rabbit anti-mouse antibody binding to all mouse immunoglobulins (heavy and light chains). Thus, only 1 labeled antibody is needed for all assays. The advantages of the method described are the following: results are obtained within a few hours and antibody containing hybridoma supernatants may be used without a concentration step since minute amounts of antibody are detected by the immunoradiometric assay. Cultures producing several subclasses may be early recognized as oligo/polyclonal. (Auth.)

VH repertoire in progeny of long term lymphoid-cultured cells used to reconstitute immunodeficient mice

International Nuclear Information System (INIS)

Denis, K.A.; Timson, L.K.; Witte, O.N.

1989-01-01

VH gene utilization in the progeny of long term lymphoid-cultured cells used for reconstitution of severe combined immunodeficient mice under varying conditions was determined. Hybridomas made from the spleens of these animals were evaluated for clonality and donor origin and a panel of 146 independent hybridomas were subsequently examined for VH expression. Hybridomas derived from the spleens of SCID mice reconstituted with fresh cells, used as a control, utilized VH families in proportion to their numerical representation in the genome. However, hybridomas from the spleens of mice reconstituted with long term cultured cells utilized a predominance of the two VH gene families most proximal to JH, characteristic of cells early in B lymphocyte development. Coinjection of thymocytes with cultured fetal liver cells, to provide good levels of T lymphocytes, did not alter this pattern of VH utilization. Irradiation (3 Gy) of the mice before cultured cell injection, which leads to more complete reconstitution of the B cell compartment, was effective in removing this bias in the VH repertoire. Hybridomas derived from these mice expressed their VH genes more in proportion to family size, characteristic of cells later in B lymphocyte development. In this manner, long term lymphoid-cultured cells can be used to study the transitions that occur in VH repertoire expression which appear to be mediated by either B lymphocyte developmental microenvironment or population size

Descripción de un inmunoensayo enzimático que reconoce anticuerpos anti-factor VIII/von Willebrand obtenidos a partir de hibridomas múridos Description of an enzime immunoassay that recognizes anti-factor VIII/von Willebrand antibodies obtained from murine hybridomas

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Renée González Sampedro

1999-04-01

Full Text Available Se describe un inmunoensayo enzimático (ELISA que detecta anticuerpos anti-Factor-VIII/von Willebrand (FVIII/vW, con una relación de enlace > 5, que permite reconocer dichos anticuerpos tempranamente en los cultivos de hibridomas múridos. Para la adsorción de las placas del inmunoensayo se utilizaron preparados semipurificados de FVIII/vW obtenidos en Cuba. Se inmunizaron ratones Balb/c con la finalidad de generar los anticuerpos monoclonales detectados por este ELISA. Se obtuvo un clon con crecimiento estable y varios subclones positivos por el ELISA con actividad biológica específica de anticuerpos inhibidores de FVIIIAn enzime immunoassay (ELISA that detects anti-Factor VIII/von Willebrand (FVIII/vw antibodies with a binding relationship > 5 that allows the early recognition of such antibodies in the cultures of murine hybridomas is described. Semipurified preparations of FVIII/vw obtained in Cuba were used for the adsorption of the immunoassay plates. Balb/c mice were immunized in order to generate the monoclonal antibodies detected by this ELISA. A clone with stable growth and several positive subclones were obtained by ELISA with specific biological activity of FVIII-inhibiting antibodies

Myeloma-Derived Light Chain Paired with a Diagnostic Monoclonal Antibody Hinders Immunoassay Performance.

Science.gov (United States)

Tu, Bailin; Tieman, Bryan; Moore, Jeffrey; Pan, You; Muerhoff, A Scott

2017-06-01

Monoclonal antibodies are widely used as the capture and detection reagents in diagnostic immunoassays. In the past, myeloma fusion partners expressing endogenous heavy and/or light chains were often used to generate hybridoma cell lines. As a result, mixed populations of antibodies were produced that can cause inaccurate test results, poor antibody stability, and significant lot-to-lot variability. We describe one such scenario where the P3U1 (P3X63Ag8U.1) myeloma fusion partner was used in the generation of a hybridoma producing protein induced vitamin K absence/antagonist-II (PIVKA II) antibody. The hybridoma produces three subpopulations of immunoglobulin as determined by ion exchange (IEx) chromatography that exhibit varying degrees of immunoreactivity (0%, 50%, or 100%) to the target antigen as determined by Surface Plasmon Resonance. To produce an antibody with the highest possible sensitivity and specificity, the antigen-specific heavy and light chain variable domains (VH and VL) were cloned from the hybridoma and tethered to murine IgG1 and kappa scaffolds. The resulting recombinant antibody was expressed in Chinese hamster ovary cells and is compatible for use in a diagnostic immunoassay.

Distinct accessory cell requirements define two types of rat T cell hybridomas specific for unique determinants in the encephalitogenic 68-86 region of myelin basic protein

International Nuclear Information System (INIS)

Mannie, M.D.; Paterson, P.Y.; Thomas, D.W.; Nairn, R.

1990-01-01

Six clonotypically unique T cell hybridomas from Lewis rats were used to study accessory cell activities required for class II MHC restricted T cell responses to the 68-86 encephalitogenic sequence of myelin basic protein (MBP). T cell hybrids which were cultured with GP68-86 68-86 sequence of guinea pig MBP (GPMBP) and naive splenocytes (SPL) were induced to produce IL-2 as measured by the CTLL indicator cell line. The hybrids were categorized into two subsets (designated THYB-1 and THYB-2), because two distinct subset-specific pathways of communication between accessory cells and T cells were involved in GPMBP-induced IL-2 production. These pathways were distinguished by the following six observations. First, when the duration of a pulse of SPL with GPMBP was lengthened from 1 to 4 h, these SPL lost their ability to induce IL-2 production by THYB-2 hybrids yet nevertheless retained full stimulatory activity for THYB-1 hybrids. Second, paraformaldehyde fixation of GPMBP-pulsed SPL abrogated an activity necessary for Ag-induced IL-2 production by THYB-2 hybrids. These fixed SPL were nevertheless able to stimulate THYB-1 hybrids, albeit to a lesser extent than viable unfixed SPL. Third, the addition of either cycloheximide, cytochalasin B, or 2-deoxyglucose to an Ag pulse of SPL with GPMBP dramatically inhibited the subsequent responses of THYB-2 hybrids yet had little or no effect upon the reactivity of THYB-1 hybrids. Fourth, thymocytes lacked necessary activities for GPMBP evoked IL-2 production by THYB-2 hybrids yet strongly promoted THYB-1 hybrid responses. Fifth, exposure of SPL to as little as 500 rad of gamma-irradiation markedly attenuated THYB-2 hybrid response to GPMBP but did not affect THYB-1 responses. Sixth, anti-GPMBP responses by THYB-2 hybrids were observed only in the presence of both radioresistant adherent SPL and a distinct population of radiosensitive nonadherent SPL

Determination of mycroplasmic contamination by radiometric method

International Nuclear Information System (INIS)

Khashimova, Z.S.

2004-01-01

Full text: Some species of mycoplasmas are pathogenic for man, animals and plants. The problem of mycoplasmic contamination of cultivated cells used in biotechnology for producing of monoclonal antibodies and vaccines is very actual. The plasmatic membrane of mycoplasmas, which does not differ on its structural organization from a membrane of eucariotic cells, takes part in formation of strong surface antigens. Taking into account this fact, it has been investigated mycoplasmic contamination of several kinds of cotton seeds, myelome cells XAg8.653, and hybridoma cells producing monoclonal antibodies to cotton membrane proteins. Mycoplasmic contamination was determined by hybridization of DNA of investigated objects with recombinant plasmids containing mycoplasmas DNA fragments. DNA was isolated from 5 kinds of cotton seedling, cellular cultures and hybridomas according to standard protocols. DNA was denaturated, neutralized and a reaction mix was transferred to nitrocellulose filter. Than filters were hybridizated with universal plasmid sounds namely pMg16 and pAl32, which contained the mycoplasma genomic fragment. These sounds were constructed in the Institute of Cytology of Russian Academy of Science by Borhsenius S.N. at al. [1] and kindly given us for our work. pMg16 and pAl32 were preliminary marked by 32 P - ATP (nick - translation). Hybridization was carried out within night. Filters were washed and placed for radioautography at - 70 o C for 24h. Sensitivity of 32 P - labeled probes in reaction was 1ng of mycoplasmas DNA. It was shown, that only one kind of cotton seeds was not contaminated by mycoplasmas, and hybridoma and myeloma cells was not contaminated. Thus, the presence of mycoplasmas in different objects may be determined using DNA hybridization. This work was supported by the Center of Science and Technology RU (4F No 419)

Sponge Hybridomas: Applications and Implications

NARCIS (Netherlands)

Pomponi, S.A.; Jevitt, A.; Patel, J.; Diaz, M.C.

2013-01-01

Many sponge-derived natural products with applications to human health have been discovered over the past three decades. In vitro production has been proposed as one biological alternative to ensure adequate supply of marine natural products for preclinical and clinical development of drugs.

Produksi dan Karakterisasi Antibodi Monoklonal Anti-Cysticercus cellulosae (PRODUCTION AND CHRACTERIZATION OF MONOCLONAL ANTIBODIES AGAINST CYSTICERCUS CELLULOSAE

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Ida Bagus Ngurah Swacita

2015-10-01

Full Text Available The purpose of this study is to make a monoclonal antibody against- Cysticercus cellulosae and itscharacterization. Samples antigen prepared from T. solium larvae (C. cellulosae was then used to immunizeBalb/c. The immune response of mice assessed by ELISA test, then the lymphocytes of mice used for theproduction of monoclonal antibodies (MoAb. Origin lymphocytes of mice that produce antibodies againstC. cellulosae antigen, fused with myeloma cells (NS1. Results fusion of two cells produces hybrid cellscalled hybridomas; cells are then screened by ELISA test. Hybridoma cells that produce only MoAb, usedto produce large quantities in vitro. Characterization of MoAb against-C.cellulosae was tested by usingELISA and Western blotting. Mice were immunized with C.cellulosae antigen showed an immune responseproducing antibodies to C.cellulosae. Based on the results of fusion, produced a total of 51 hybridoma cellclones and after being screened, only three clones of hybridoma cells that produced MoAb against–C.cellulosae. MoAb produced, named after the hole where the growth of the ELISA micro plate, the BE6,BE7, and EE9. Characteristics of this MoAb capable of tracking cellulosae of fluid larvae and recognizeantigen protein bands with molecular weight 78kDa.

Production of Monoclonal Antibodies specific for Progesterone

OpenAIRE

YÜCEL, Fatıma

2014-01-01

Progesterone levels in milk and serum are indicators of pregnancy in cattle. The progesterone level reaches a peak on the 21 st and 22 nd days of pregnancy. Monoclonal antibodies specific to progesterone could be used for the immunodetection of milk and serum progesterone levels. We report here the development of hybrid cells prdoducing monoclonal antibodies specific for progesterone using hybridoma technology. Hybridoma cells secreting monoclonal antibodies against progesterone (MAM 2H1...

Developmental fate of hematopoietic stem cells: the study of individual hematopoietic clones at the level of antigen-responsive B lymphocytes.

Science.gov (United States)

Olovnikova, Natalia I; Drize, Nina J; Ershler, Maxim A; Nifontova, Irina N; Belkina, Elena V; Nikolaeva, Tatiana N; Proskurina, Natalia V; Chertkov, Joseph L

2003-01-01

We have shown previously that hematopoiesis in mice reconstituted with retrovirally marked hematopoietic stem cells (HSCs) is provided by multiple, mainly short-lived clones, as measured by retroviral insertion site analysis of individual spleen colony-forming unit (CFU-S)-derived colonies. However, the CFU-S is the relatively early progenitor and the contribution of each CFU-S in the steady-state hematopoiesis is uncertain. Here, we have studied the fate of individual mature B cells, as well as CFU-S, representing the progeny of retrovirally transduced marrow-repopulating cells (MRC). B-cells-generated hybridomas and CFU-S-derived colonies were used to determine the clonal composition of hematolymphopoiesis at the single-cell level. Bone marrow (BM) cells and splenocytes (approximately 1/3-1/2 of spleen at a time) from mice reconstituted with retrovirally marked syngeneic BM cells were repeatedly collected at 3, 10, and 16 months post-transplant. The percentage of retrovirally marked CFU-S and B-cell-produced hybridomas was about 50% at 3 months and decreased to 10-15% at 10 months after reconstitution in spite of stable degree of chimerism. The clonal origin of BM-derived CFU-S and spleen-derived B-cell hybridomas was detected by Southern blot analysis. Overall, DNA obtained from 159 retrovirally marked spleen colonies, 287 hybridomas and 43 BM samples were studied. Multiple simultaneously functioning clones of MRC-derived B cells were observed. The same individual clones among hybridomas and CFU-S were identified in three out of 11 mice. Thus, hematopoiesis is generated by multiple hematopoietic clones some of which can simultaneously contribute to both mature lymphoid cells and myeloid progenitors. These data establish that the stem cell compartment functions by continuously producing progeny, which fully but transiently repopulate all lineages.

Actions of Interferons on Macrophages.

Science.gov (United States)

1984-06-01

cell productin celular immunity. The following is a list of our accomplishments. 1. The successful immunization of rats with a partially purified IFNy...antibbdy (MAb) was cloned . 3. The hybridoma producing rat anti-MuiFN*MAb has proven stable and is being propagated both in vitro and as well as in vivo in...containing 20% FBS. The cloned hybridoma (R4-6A2) was expanded and the isotype of monoclonal antibody (MAb) produced by this clone was determined to be in

PRODUÇÃO DE HIBRIDOMAS SECRETORES DE ANTICORPOS ANTI- Neospora caninum PARA USO EM IMUNODIAGNÓSTICO

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Bruna Alves Devens

2014-06-01

Full Text Available The Neospora caninum is a protozoan Apicomplexa with greater involvement in abortions worldwide. The economic losses determined by neosporosis also include abortions besides the early disposal of cows, costs for replacing animals in the herd, drop in milk production as well as milk in fat production. The immunological diagnosis involves purchasing costly diagnostic kits on the market. Therefore, the aim of this study was the production of hybridomas secreting polyclonal antibodies with affinity to Neospora caninum (Nc-1 strain for immunodiagnostic use. For antibodies production, we used sonicated protozoa from Vero cells in culture, purified by filtration. These tachyzoites were employed for immunization of BALB / c mice using saponin as adjuvant, which allowed obtaining polyclonal antibodies capable of revealing fluorescein reaction in indirect immunofluorescence. The fusion of splenic cells, from the immunized mice with myeloma cells SP2 / 0 resulted in 72.4% hybridomas secreting anti-Nc-1antibodies. These hybridomas secreted antibodies positive to N. caninum and negative to Toxoplasma gondii.

Three monoclonal antibodies to the VHS virus glycoprotein: comparison of reactivity in relation to differences in immunoglobulin variable domain gene sequences

DEFF Research Database (Denmark)

Lorenzen, Niels; Cupit, P.M.; Secombes, C.J.

2000-01-01

and their neutralising activity was evident. Binding kinetic analyses by plasmon resonance identified differences in the dissociation rate constant (kd) as a possible explanation for the different reactivity levels of the MAbs. The Ig variable heavy (VH) and light (V kappa) domain gene sequences of the three hybridomas...... were compared. The inferred amino acid sequence of the two neutralising antibody VH domains differed by three amino acid residues (97% identity) and only one residue difference was evident in the Vk. domains. In contrast, IP1H3 shared only 38 and 39% identity with the 3F1A2 and 3F1H10 VH domains...... respectively and 49 and 50% identity with the 3F1A2 and 3F1H10 VK domains respectively. The neutralising antibodies were produced by hybridomas originating from the same fusion and the high nucleotide sequence homology of the variable Ig gene regions indicated that the plasma cell partners of the hybridomas...

New strategies for designing inexpensive but selective bioadsorbants for environmental pollutants: Selection of specific ligands and their cell surface expression. Technical progress report, September 15, 1996 -September 14, 1997

International Nuclear Information System (INIS)

Iverson, B.

1997-01-01

'Progress for the last twelve months has revolved around setting up an antibody engineering and surface display system for use with a metal-complex binding antibody. (1) The author has isolated genes for the V regions of the heavy and light chains for the Ru(bpy)3 specific monoclonal AC1106 (Shreder, K S., Hariman, A., and Iverson, B.L., J. Am. Chem. Soc. 1996, 118, 3192-3201). This antibody binds Ru(bpy), derivatives with better than nanomolar affinity, and will serve as the generic metal-complex binding pocket. Cloning antibody genes from hybridomas is complicated by the fact that primers must be found that amplify the particular heavy and light chain genes in the hybridoma of interest. Antibody gene amplification primers are generally designed to amplify antibody repertoires from lymphocyte mRNA isolated from animals. While cloning repertoires from animals is routinely successful due to the diverse population of target m RNA, hybridomas have a single target sequence. Therefore, multiple primers and conditions must be tried before the correct primer combination is identified.'

Monoclonal antibodies to antigens on human neutrophils, activated T lymphocytes, and acute leukemia blast cells

International Nuclear Information System (INIS)

Miterev, G.Yu.; Burova, G.F.; Puzhitskaya, M.S.; Danilevich, S.V.; Bulycheva, T.I.

1987-01-01

The authors describe the production of two mouse hybridomas secreting monoclonal antibodies to antigenic determinants of the surface membranes of human neutrophils, activated T lymphocytes, and acute leukemic blast cells. The degree of lymphocyte stimulation was estimated from incorporation of 3 H-thymidine with parallel microculture. Monoclonal antibodies of supernatants of hybridoma cultures shown here reacted in both immunofluorescence test and cytotoxicity test with surface membrane antigens on the majority of neutrophils and PHA-activated peripheral blood lymphocytes from healthy subjects, but did not give positive reactions with unactivated lymphocytes, adherent monocytes, erythrocytes, and alloantigen-stimulated lymphocytes

Monoclonal antibodies to antigens on human neutrophils, activated T lymphocytes, and acute leukemia blast cells

Energy Technology Data Exchange (ETDEWEB)

Miterev, G.Yu.; Burova, G.F.; Puzhitskaya, M.S.; Danilevich, S.V.; Bulycheva, T.I.

1987-11-01

The authors describe the production of two mouse hybridomas secreting monoclonal antibodies to antigenic determinants of the surface membranes of human neutrophils, activated T lymphocytes, and acute leukemic blast cells. The degree of lymphocyte stimulation was estimated from incorporation of /sup 3/H-thymidine with parallel microculture. Monoclonal antibodies of supernatants of hybridoma cultures shown here reacted in both immunofluorescence test and cytotoxicity test with surface membrane antigens on the majority of neutrophils and PHA-activated peripheral blood lymphocytes from healthy subjects, but did not give positive reactions with unactivated lymphocytes, adherent monocytes, erythrocytes, and alloantigen-stimulated lymphocytes.

Expression and purification of a major allergen, Pla a 1, from Platanus acerifolia pollen and the preparation of its monoclonal antibody.

Science.gov (United States)

Ni, Wei-Wei; Huang, Wen; Wu, De-Qin; Zhou, Yan-Jun; Ji, Chun-Mei; Cao, Meng-Da; Guo, Miao; Sun, Jin-Lu; Wei, Ji-Fu

2017-09-01

Platanus acerifolia pollen is considered an important source of airborne allergens in numerous cities. Pla a 1 is a major allergen from P. acerifolia pollen. The present study aimed to express and purify Pla a 1, and to prepare its monoclonal antibody. In the present study, the Pla a 1 gene was subcloned into a pET‑28a vector and transformed into the ArcticExpress™ (DE3) RP Escherichia coli host strain. The purified Pla a 1 was then used to immunize BALB/c mice. When serum detection was positive, spleen cells were isolated from the mice and fused with SP2/0 myeloma cells at a ratio of 10:1. Hybridoma cells were screened by indirect ELISA and limiting dilution. Positive cells were used to induce the formation of antibody‑containing ascites fluid, and the antibodies were purified using protein A‑agarose. The results of the present study demonstrated that recombinant Pla a 1 was successfully expressed and purified, and exhibited positive immunoglobulin E‑binding to serum from patients allergic to P. acerifolia. A total of 11 hybridomas that steadily secreted anti‑Pla a 1 antibody were obtained and an immunoblotting analysis indicated that all of these monoclonal antibodies specifically recognized the Pla a 1 protein. These results suggested that specific anti‑Pla a 1 antibodies may be obtained, which can be used for the rapid detection of Pla a 1 allergens and in the preparation of vaccines against P. acerifolia pollen.

Monoclonal antibodies to drosophila cytochrome P-450's

International Nuclear Information System (INIS)

Sundseth, S.S.; Kennel, S.J.; Waters, L.C.

1987-01-01

Hybridomas producing monoclonal antibodies were prepared by the fusion of SP2/0 myeloma cells and spleen cells from a female BALB/c mouse immunized by cytochrome P-450-A and P-450-B purified from Drosophila Hikone-R (BG) microsomes. P-450-A and P-450-B are electrophoretically distinct subsets of Drosophila P-450. P-450-A is ubiquitous among strains tested, while P-450-B is present in only a few strains displaying unique enzyme activities and increased insecticide resistance. The Oregon-R strain contains only cytochromes P-450-A and is susceptible to insecticides. The authors Hikone-R (BG) strain expresses both cytochromes P-450-A and P-450-B and is insecticide resistant. Antibody producing hybridomas were detected in a solid-phase radioimmunoassay (RIA) by binding to Hikone-R (BG) or Oregon-R microsomes. Four independent hybridomas were identified as producing monoclonal antibodies that recognized proteins in the P-450 complex by immunoblot experiments. Three monoclonal antibodies recognized P-450-A proteins, while one monoclonal antibody bound predominantly P-450-B. This monoclonal antibody also recognized southern armyworm (Spodoptera eridania, Cramer) microsomal proteins

Densities and Kinematic Viscosities for the Systems Benzene + Methyl Formate, Benzene + Ethyl Formate, Benzene + Propyl Formate, and Benzene + Butyl Formate

DEFF Research Database (Denmark)

Emmerling, Uwe; Rasmussen, Peter

1998-01-01

a Redlich-Kister type of expression with temperature-independent parameters and the data for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate with temperature-dependent parameters. The viscosities have furthermore been compared to values predicted by means of the GC......Densities and kinematic viscosities have been measured for the system benzene + methyl formate at 20°C and for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate from 20°C to 50°C. The results for the system benzene + methyl formate have been correlated using...

Strategies for the detection of food pathogens and contaminants

DEFF Research Database (Denmark)

Hearty, Stephen; Leonard, Paul; Sheehan, Alfredo Darmanin

molecules and once suitably high affinity antibodies have been isolated, it is relatively straightforward to design and optimise concentration-based assays using SPR. Recently we have investigated the potential of applying Biacore technology to routine food analysis. Our experiences have shown......We routinely use Biacore for affinity ranking and kinetic characterisation of diverse panels of hybridoma-derived and recombinant antibodies against a wide range of different clinically relevant antigens for diagnostic applications. Generally the analytes of interest are haptens or defined protein...... that molecular contaminants such as microbial toxins and drug/pesticide residues translate well onto Biacore-based assay formats. However, larger and more complex entities such as spores and whole bacterial cells represent an altogether more difficult challenge. Here, we present an overview of our experiences...

Development of Methods to Isolate Recombinant Antibodies Against Prostate Cancer Antigens

National Research Council Canada - National Science Library

Williams, Myron

2000-01-01

.... Appropriate materials, which include prostate cancer (PCa) cell lines, tissue specimens from radical prostacetomies, and hybridomas producing antibodies specific for pro static antigens have been procured...

Formate Formation and Formate Conversion in Biological Fuels Production

Directory of Open Access Journals (Sweden)

Bryan R. Crable

2011-01-01

Full Text Available Biomethanation is a mature technology for fuel production. Fourth generation biofuels research will focus on sequestering CO2 and providing carbon-neutral or carbon-negative strategies to cope with dwindling fossil fuel supplies and environmental impact. Formate is an important intermediate in the methanogenic breakdown of complex organic material and serves as an important precursor for biological fuels production in the form of methane, hydrogen, and potentially methanol. Formate is produced by either CoA-dependent cleavage of pyruvate or enzymatic reduction of CO2 in an NADH- or ferredoxin-dependent manner. Formate is consumed through oxidation to CO2 and H2 or can be further reduced via the Wood-Ljungdahl pathway for carbon fixation or industrially for the production of methanol. Here, we review the enzymes involved in the interconversion of formate and discuss potential applications for biofuels production.

Galaxy formation

International Nuclear Information System (INIS)

Silk, J.; Di Cintio, A.; Dvorkin, I.

2014-01-01

Galaxy formation is at the forefront of observation and theory in cosmology. An improved understanding is essential for improving our knowledge both of the cosmological parameters, of the contents of the universe, and of our origins. In these lectures intended for graduate students, galaxy formation theory is reviewed and confronted with recent observational issues. In lecture 1, the following topics are presented: star formation considerations, including IMF, star formation efficiency and star formation rate, the origin of the galaxy luminosity function, and feedback in dwarf galaxies. In lecture 2, we describe formation of disks and massive spheroids, including the growth of supermassive black holes, negative feedback in spheroids, the AGN-star formation connection, star formation rates at high redshift and the baryon fraction in galaxies.

37 CFR 1.710 - Patents subject to extension of the patent term.

Science.gov (United States)

2010-07-01

... of Patent Term Extension of Patent Term Due to Regulatory Review § 1.710 Patents subject to extension... primarily manufactured using recombinant DNA, recombinant RNA, hybridoma technology, or other processes...

Use of a solid-phase 3H-radioimmunoassay for the measurement of immunoglobulin produced in short-term cultures of antibody-secreting cells

International Nuclear Information System (INIS)

Mongini, P.K.A.; Heber-Katz, E.

1982-01-01

A solid-phase radioimmunoassay (RIA) for assaying immunoglobulin produced from antibody-secreting myeloma, hybridoma and immune spleen cells is described. Specific antibody is detected by culturing antibody-producing cells on antigen-coated flexible polyvinylchloride microtiter wells, washing away the cells, and measuring the bound specific antibody with tritiated affinity-purified anti-isotype reagents. Antibody produced from 10 3 myeloma cells can be detected with as little as 4 h of incubation. With 24-48 h of incubation, antibody from as few as approximately 3-15 myeloma, hybridoma or immune spleen plaque-forming cells (PFC) can be detected. This culture-well RIA has certain distinct advantages over the hemolytic PFC assay and RIA assays in which antibody in culture supernatants is measured. (Auth.)

Stellar formation

CERN Document Server

Reddish, V C

1978-01-01

Stellar Formation brings together knowledge about the formation of stars. In seeking to determine the conditions necessary for star formation, this book examines questions such as how, where, and why stars form, and at what rate and with what properties. This text also considers whether the formation of a star is an accident or an integral part of the physical properties of matter. This book consists of 13 chapters divided into two sections and begins with an overview of theories that explain star formation as well as the state of knowledge of star formation in comparison to stellar structure

Parallel optical information, concept, and response evolver: POINCARE

Science.gov (United States)

Caulfield, H. John; Caulfield, Kimberly

1991-08-01

It is now possible to build a nonlinear adaptive system which will incorporate many of the properties of the human mind, such as true originality in such skills as reasoning by analogy and reasoning by retrodiction, including literally unpredictable thoughts; and development of individual styles, personalities, expertise, etc. Like humans, these optical processors will have a rich `subconscious'' experience. Like humans, they will be clonable, but clones will develop differently as they experience the world differently, make different decisions, develop different habits, etc. In short, powerful optical processors with some of the properties normally associated with human intelligence can be made. This approach can result in a powerful optical processor with those properties. A demonstration chosen for simplicity of implementation is suggested. This could be the first computer of any type which uses quantum indeterminacy in an integral and important way.

First insight into the genome of an uncultivated crenarchaeote from soil

DEFF Research Database (Denmark)

Quaiser, Achim; Ochsenreiter, Torsten; Klenk, Hans-Peter

2002-01-01

RNA genes and of several protein encoding genes (e.g. DNA polymerase, FixAB, glycosyl transferase) confirmed the specific affiliation of the genomic fragment with the non-thermophilic clade of the crenarchaeota. Content and structure of the genomic fragment indicated that the archaea from soil differ......Molecular phylogenetic surveys based on the characterization of 16S rRNA genes have revealed that soil is an environment particularly rich in microbial diversity. A clade of crenarchaeota (archaea) has frequently been detected among many other novel lineages of uncultivated bacteria. In this study...... we have initiated a genomic approach for the characterization of uncultivated microorganisms from soil. We have developed a procedure based on a two-phase electrophoresis technique that allows the fast and reliable purification of concentrated and clonable, high molecular weight DNA. From this DNA we...

A human/mouse chimeric monoclonal antibody against intercellular adhesion molecule-1 for tumor radioimmunoimaging

International Nuclear Information System (INIS)

Yamamura, Miyuki; Hinoda, Yuji; Sasaki, Shigeru; Tsujisaki, Masayuki; Imai, Kohzoh; Oriuchi, Noboru; Endo, Keigo.

1996-01-01

A mouse-human chimeric antibody for intercellular adhesion molecule-1 (ICAM-1) was established by using heavy chain loss mouse mutant hybridoma and human immunoglobulin expression vector. The HA58 hybridoma secreted anti-ICAM-1 monoclonal antibody (MoAb) (IgG1,κ). The gene of the mouse variable region of heavy chain was amplified and cloned by the polymerase chain reaction technique directly from the HA58 hybridoma RNA. The variable region of heavy chain was joined with an expression vector which contains human γ1 constant gene. The expression vector was transfected into heavy chain loss mutant cells HA58-7, which produced only murine immunoglobulin light chains. The resultant chimeric MoAb HA58, chHA58, retained full-binding reactivity to ICAM-1 compared with murine HA58 parental antibody. The chimeric MoAb chHA58 showed little antibody dependent cell-mediated cytotoxic activity against cultured tumor cells. Biodistribution studies with 99m Tc-labeled chHA58 in nude mice bearing human gastric carcinoma JRST cells, demonstrated that the tumor-blood ratio was 1.55 at 18 h after injection, when the tumors were clearly visible in gamma scintigraphy. These data suggest that chHA58 may be of practical use for radioimmunoimaging of a wide variety of tumors. (author)

Detection of Human Epididymis Protein 4 (HE4) in Human Serum Samples Using a Specific Monoclonal Antibody-Based Sandwich Enzyme-Linked Immunosorbent Assay (ELISA).

Science.gov (United States)

Zhou, Lijun; Lv, Zhiqiang; Shao, Jing; Xu, Ying; Luo, Xiaohong; Zhang, Yuming; Hu, Yang; Zhang, Wenji; Luo, Shuhong; Fang, Jianmin; Wang, Ying; Duan, Chaohui; Huang, Ruopan

2016-09-01

The human epididymis protein 4 (HE4) may have high specificity in the detection of malignant diseases, making the development of an immunoassay for HE4 essential. In our study, a fusion gene was constructed encoded with the HE4 protein. This protein was then produced in the bacterial cells (Escherichia coli) and used to immunize mice in order to eventually generate hybridomas specific to HE4. The hybridoma supernatants were then screened, and four positive anti-HE4 cell lines were selected. These cell lines produce monoclonal antibodies against HE4 epitopes, as demonstrated in the Western blot as well as by direct enzyme-linked immunosorbent assay (ELISA). Using the developed antibodies, we successfully identified several good antibody pairs from the hybridomas, which allowed for the development of a sandwich ELISA to measure HE4 levels. By using the HE4 ELISA, we measured HE4 levels of 60 clinical human serum samples. Compared with the Food and Drug Administration (FDA) approved kit (Roche), our results showed a strong positive correlation to those of the FDA-approved kit. In summary, highly sensitive antibody pairs were screened against HE4, and a sandwich ELISA was developed as an accurate analytical tool for the detection of HE4 in human serum, which could be especially valuable for diagnosing ovarian carcinomas. © 2015 Wiley Periodicals, Inc.

Satellite formation flying relative dynamics, formation design, fuel optimal maneuvers and formation maintenance

CERN Document Server

Wang, Danwei; Poh, Eng Kee

2017-01-01

This book systematically describes the concepts and principles for multi-satellite relative motion, passive and near passive formation designs, trajectory planning and control for fuel optimal formation maneuvers, and formation flying maintenance control design. As such, it provides a sound foundation for researchers and engineers in this field to develop further theories and pursue their implementations. Though satellite formation flying is widely considered to be a major advance in space technology, there are few systematic treatments of the topic in the literature. Addressing that gap, the book offers a valuable resource for academics, researchers, postgraduate students and practitioners in the field of satellite science and engineering.

Production and characterization of monoclonal antibodies specific to the strobilurin pesticide pyraclostrobin.

Science.gov (United States)

Mercader, Josep V; Suárez-Pantaleón, Celia; Agulló, Consuelo; Abad-Somovilla, Antonio; Abad-Fuentes, Antonio

2008-09-10

Strobilurin fungicides are nowadays among the most important fungicides in the market of active agrochemicals. Pyraclostrobin, which belongs to the last generation of this family of molecules, shows a broader antifungal activity spectrum and higher efficiency and security profiles than previous fungicides. This paper describes the synthesis of functionalized haptens, the production of monoclonal antibodies, and the development of enzyme-linked immunosorbent assays (ELISA) for the detection of pyraclostrobin. A conformational analysis of hapten structure was performed, which provided relevant data concerning the length of the spacer arm. A very useful strategy has been followed for the screening of hybridomas, leading to the selection of a panel of high-affinity monoclonal antibodies to pyraclostrobin. Moreover, different immunoassays have been characterized using the conjugate-coated indirect ELISA format, and limits of detection below 0.1 microg/L have been obtained. Also, a simplified one-step procedure has been carried out with two indirect assays. Finally, these results have been compared with the performance of the same antibodies in the antibody-coated direct ELISA format.

Localisation of metastatic carcinoma by a radiolabelled monoclonal antibody

Energy Technology Data Exchange (ETDEWEB)

Smedley, H M; Ritson, A; Wraight, P; Sikora, K [Addenbrooke' s Hospital, Cambridge (UK); Hinchingbrooke Hospital, Huntingdon (UK)); Finan, P [St. James Hospital, Leeds (UK); Lennox, E S; Takei, F [Medical Research Council, Cambridge (UK)

1983-02-01

Rat monoclonal antibodies were prepared by immunising rats with human colorectal carcinoma cell membranes and fusing splenic lymphocytes with a rat myeloma. Hybridoma supernatants were screened by binding assays on membranes prepared from colorectal carcinoma tissue. One hybridoma supernatant, containing a monoclonal antibody with high binding activity on malignant compared to normal colon sections, was grown in large quantities in serum-free medium. After ammonium sulphate precipitation the antibody was purified by ion-exchange chromatography and labelled with /sup 131/I. Radiolabelled antibody was administered i.v. to 27 patients with colonic and other tumours. Scintigrams were obtained at 48 h. Computerised subtraction of the blood pool image revealed localised areas of uptake corresponding with areas of known disease in 13/16 patients with colorectal carcinoma and 3/4 patients with breast cancer.

Why adult formation

Directory of Open Access Journals (Sweden)

Andrej Justinek

1997-01-01

Full Text Available The article argues that the primary aim of adult formation is comprehensive personality development which is supposed to ensure quality existence in modern world. The article also suggests that formarion is a permanent process. Justinek puts special emphasis on adult formation methodology and defines fundamental formation styles which encourage independent action in individuals. Justinek differentiates between formation and education. methods and concludes that formation methods are related to the emotional sphere of personality, and education methods mostly to the rational. Justinek believes that formation of adults is based primarily on appropriate formation methodology.

Advances in diagnosis of livestock diseases

African Journals Online (AJOL)

It is11 manipulative ecology with its basic operational unit being the complex producl ion system influenced by interactions ..... chain reaction (PCR), and recombinant DNA and hybridoma ... nucle9tides which form the building blocks for DNA.

Browse Title Index

African Journals Online (AJOL)

2004), Cell cycle analysis of interleuklin-6 Stimulated B9 hybridoma cell line in ... and Sediment Parameters of Jisike-Izombe Upper Aquifer System for ... Vol 17, No 3 (2013), Chemical Compositions of Soils in Parts of ...

Use of monoclonal-antibodies for the detection of fecal bacteria in water

CSIR Research Space (South Africa)

Kfir, R

1993-01-01

Full Text Available Monoclonal antibodies (MAbs) against heat-killed Escherichia coli and Klebsiella oxytoca originating from wastewater effluent were raised in BALB/C mice. The fusion was highly successful and three hybridomas cloned were selected to study...

Multiplexed Quantitation of Intraphagocyte Mycobacterium tuberculosis Secreted Protein Effectors

Directory of Open Access Journals (Sweden)

Fadel Sayes

2018-04-01

Full Text Available Summary: The pathogenic potential of Mycobacterium tuberculosis largely depends on ESX secretion systems exporting members of the multigenic Esx, Esp, and PE/PPE protein families. To study the secretion and regulation patterns of these proteins while circumventing immune cross-reactions due to their extensive sequence homologies, we developed an approach that relies on the recognition of their MHC class II epitopes by highly discriminative T cell receptors (TCRs of a panel of T cell hybridomas. The latter were engineered so that each expresses a unique fluorescent reporter linked to specific antigen recognition. The resulting polychromatic and multiplexed imaging assay enabled us to measure the secretion of mycobacterial effectors inside infected host cells. We applied this novel technology to a large panel of mutants, clinical isolates, and host-cell types to explore the host-mycobacteria interplay and its impact on the intracellular bacterial secretome, which also revealed the unexpected capacity of phagocytes from lung granuloma to present mycobacterial antigens via MHC class II. : Sayes et al. develop an approach to express distinct fluorescent reporters that is based on the recognition of specific Mycobacterium tuberculosis MHC class II epitopes by highly discriminative T cell hybridomas. This multiplexed technology allows the study of secretion, subcellular location, and regulation patterns of these instrumental protein members. Keywords: mycobacterium tuberculosis, type VII secretion systems, intracellular bacteria, T-cell hybridomas, mycobacterial virulence factors, bacterial antigen presentation, lentiviral vectors, reporter T cells, in vivo antigen presentation, protein localization

Generation of HER2 monoclonal antibodies using epitopes of a rabbit polyclonal antibody.

Science.gov (United States)

Hu, Francis Jingxin; Uhlen, Mathias; Rockberg, Johan

2014-01-25

One of the issues in using polyclonal antibodies is the limited amount of reagent available from an immunisation, leading to batch-to-batch variation and difficulties in obtaining the same antibody performance when the same antigen is re-immunised into several separate animals. This led to the development of hybridoma technology allowing, at least theoretically, for an unlimited production of a specific binder. Nevertheless, polyclonal antibodies are widely used in research and diagnostics and there exists a need for robust methods to convert a polyclonal antibody with good binding performance into a renewable monoclonal with identical or similar binding specificity. Here we have used precise information regarding the functional recognition sequence (epitope) of a rabbit polyclonal antibody with attractive binding characteristics as the basis for generation of a renewable mouse monoclonal antibody. First, the original protein fragment antigen was used for immunisation and generation of mouse hybridoma, without obtaining binders to the same epitope region. Instead a peptide designed using the functional epitope and structural information was synthesised and used for hybridoma production. Several of the monoclonal antibodies generated were found to have similar binding characteristics to those of the original polyclonal antibody. These monoclonal antibodies detected native HER2 on cell lines and were also able to stain HER2 in immunohistochemistry using xenografted mice, as well as human normal and cancer tissues. Copyright © 2013 Elsevier B.V. All rights reserved.

[Identification and production of monoclonal antibody of Siberian tiger's immunoglobulin].

Science.gov (United States)

Zhang, Yaonglong; Zhang, Duanling; Zhou, Ming; Xue, Yuan; Hua, Yuping; Ma, Jianzhang

2010-03-01

To purify immunoglobulin (Ig) of Siberian Tiger and prepare monoclonal antibody (mAb) against the Ig,which can be used to develop immunological diagnostic kits for diagnosing infectious disease in Siberian Tiger. The Ig of Siberian tigers was purified with saturated ammonium sulfate combined with recombinant Protein G. The C57BL/6 mice were immunized with the purified Ig. Spleno-cytes of the mice immunized were collected and fused with the mouse myeloma cell line (Sp2/0-Ag14). The positive hybridoma clones were selected by ELISA and were identified by western blot. The sandwich ELISA was used to detect immunocompetence of the purified Ig and the mAb. We obtained three mouse hybridoma clones that produced mAbs against Ig of Siberian Tiger. The derived McAbs could recognize Ig heavy chain of Siberian Tiger specifically. The biological activity of the Ig and obtained McAbs also could be identified by detecting the antibody induced by panleukopenia virus (FPV-HLJ) vaccine in Siberian Tiger. The antibody also would be useful for assess the vaccine efficacy against the infectious disease on the Siberian Tiger. Protein G can be used in Ig purification of Siberian Tiger. The obtained McAbs from the hybridoma ADT11 in this study owned strong ability to bind Ig of Siberian Tiger and have a stable immunocompetence. They can be used to develop diagnostic methods for detecting infectious disease in Siberian Tiger and vaccine research.

Expression cloning and production of human heavy-chain-only antibodies from murine transgenic plasma cells

NARCIS (Netherlands)

D.D. Drabek (Dubravka); R. Janssens (Rick); Boer, E. (Ernie de); Rademaker, R. (Rik); Kloess, J. (Johannes); J.J. Skehel (John ); Grosveld, F. (Frank)

2016-01-01

textabstractSeveral technologies have been developed to isolate human antibodies against different target antigens as a source of potential therapeutics, including hybridoma technology, phage and yeast display systems. For conventional antibodies, this involves either random pairing of VH and

Contribution of Flow Cytometry to Acute Leukemia Classification in Tunisia

Directory of Open Access Journals (Sweden)

S. Feki

2000-01-01

Full Text Available The precision of immunological characterization of leukemias was improved by a certain number of technical innovations, particularly hybridoma production and standardization, resulting in monoclonal antibodies and definition of recognised cellular antigens (designated by CD: Cluster of Differentiation.

Formation Design Strategy for SCOPE High-Elliptic Formation Flying Mission

Science.gov (United States)

Tsuda, Yuichi

2007-01-01

The new formation design strategy using simulated annealing (SA) optimization is presented. The SA algorithm is useful to survey a whole solution space of optimum formation, taking into account realistic constraints composed of continuous and discrete functions. It is revealed that this method is not only applicable for circular orbit, but also for high-elliptic orbit formation flying. The developed algorithm is first tested with a simple cart-wheel motion example, and then applied to the formation design for SCOPE. SCOPE is the next generation geomagnetotail observation mission planned in JAXA, utilizing a formation flying techonology in a high elliptic orbit. A distinctive and useful heuristics is found by investigating SA results, showing the effectiveness of the proposed design process.

Monoclonal antibodies in animal production : their use in diagnostics and passive immunization

NARCIS (Netherlands)

Booman, P.

1989-01-01

One of the landmarks in immunology was the invention and development of monoclonal antibody-secreting hybridomas by Milstein and his coworkers. The enormous promise of monoclonal antibody technology, which became apparent soon after its discovery, may explain the unusual speed with which monoclonal

The classification of Sejroe group serovars of Leptospira interrogans with monoclonal antibodies

NARCIS (Netherlands)

Terpstra, W. J.; Korver, H.; van Leeuwen, J.; Klatser, P. R.; Kolk, A. H.

1985-01-01

Using the hybridoma technique we produced monoclonal antibodies to serovars of Leptospira interrogans. We focussed on serovar hardjo which is an important pathogen for humans and animals, and on other serovars of the Sejroe group. With combinations of monoclonals, characteristic patterns of

Monoclonal antibody technologies and rapid detection assays

Science.gov (United States)

Novel methodologies and screening strategies will be outlined on the use of hybridoma technology for the selection of antigen specific monoclonal antibodies. The development of immunoassays used for diagnostic detection of prions and bacterial toxins will be discussed and examples provided demonstr...

Modification of Antibody Function by Mutagenesis.

Science.gov (United States)

Dasch, James R; Dasch, Amy L

2017-09-01

The ability to "fine-tune" recombinant antibodies by mutagenesis separates recombinant antibodies from hybridoma-derived antibodies because the latter are locked with respect to their properties. Recombinant antibodies can be modified to suit the application: Changes in isotype, format (e.g., scFv, Fab, bispecific antibodies), and specificity can be made once the heavy- and light-chain sequences are available. After immunoglobulin heavy and light chains for a particular antibody have been cloned, the binding site-namely, the complementarity determining regions (CDR)-can be manipulated by mutagenesis to obtain antibody variants with improved properties. The method described here is relatively simple, uses commercially available reagents, and is effective. Using the pComb3H vector, a commercial mutagenesis kit, PfuTurbo polymerase (Agilent), and two mutagenic primers, a library of phage with mutagenized heavy and light CDR3 can be obtained. © 2017 Cold Spring Harbor Laboratory Press.

Strategies for the detection of food pathogens and contaminants

DEFF Research Database (Denmark)

Hearty, Stephen; Leonard, Paul; Sheehan, Alfredo Darmanin

2006-01-01

We routinely use Biacore for affinity ranking and kinetic characterisation of diverse panels of hybridoma-derived and recombinant antibodies against a wide range of different clinically relevant antigens for diagnostic applications. Generally the analytes of interest are haptens or defined protei...... to date with using Biacore for analysis of food contaminants and in particular the challenges associated with large analyte detection...... molecules and once suitably high affinity antibodies have been isolated, it is relatively straightforward to design and optimise concentration-based assays using SPR. Recently we have investigated the potential of applying Biacore technology to routine food analysis. Our experiences have shown...... that molecular contaminants such as microbial toxins and drug/pesticide residues translate well onto Biacore-based assay formats. However, larger and more complex entities such as spores and whole bacterial cells represent an altogether more difficult challenge. Here, we present an overview of our experiences...

Strategies for the detection of food pathogens and contaminants

DEFF Research Database (Denmark)

We routinely use Biacore for affinity ranking and kinetic characterisation of diverse panels of hybridoma-derived and recombinant antibodies against a wide range of different clinically relevant antigens for diagnostic applications. Generally the analytes of interest are haptens or defined protei...... to date with using Biacore for analysis of food contaminants and in particular the challenges associated with large analyte detection...... molecules and once suitably high affinity antibodies have been isolated, it is relatively straightforward to design and optimise concentration-based assays using SPR. Recently we have investigated the potential of applying Biacore technology to routine food analysis. Our experiences have shown...... that molecular contaminants such as microbial toxins and drug/pesticide residues translate well onto Biacore-based assay formats. However, larger and more complex entities such as spores and whole bacterial cells represent an altogether more difficult challenge. Here, we present an overview of our experiences...

High-throughput deterministic single-cell encapsulation and droplet pairing, fusion, and shrinkage in a single microfluidic device.

Science.gov (United States)

Schoeman, Rogier M; Kemna, Evelien W M; Wolbers, Floor; van den Berg, Albert

2014-02-01

In this article, we present a microfluidic device capable of successive high-yield single-cell encapsulation in droplets, with additional droplet pairing, fusion, and shrinkage. Deterministic single-cell encapsulation is realized using Dean-coupled inertial ordering of cells in a Yin-Yang-shaped curved microchannel using a double T-junction, with a frequency over 2000 Hz, followed by controlled droplet pairing with a 100% success rate. Subsequently, droplet fusion is realized using electrical actuation resulting in electro-coalescence of two droplets, each containing a single HL60 cell, with 95% efficiency. Finally, volume reduction of the fused droplet up to 75% is achieved by a triple pitchfork structure. This droplet volume reduction is necessary to obtain close cell-cell membrane contact necessary for final cell electrofusion, leading to hybridoma formation, which is the ultimate aim of this research. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

MHC class II-derived peptides can bind to class II molecules, including self molecules, and prevent antigen presentation

DEFF Research Database (Denmark)

Rosloniec, E F; Vitez, L J; Buus, S

1990-01-01

the alpha k-3 peptide binds slightly less well. These combined data, suggesting that class II-derived peptides can bind to MHC class II molecules, including the autologous molecule from which they are derived, have important implications for the molecular basis of alloreactivity and autoreactivity. Further...... found in the first and third polymorphic regions (PMR) of the A alpha k chain (alpha k-1 and alpha k-3) were capable of inhibiting the presentation of three different HEL-derived peptide antigens to their appropriate T cells. In addition, the alpha k-1 peptide inhibited the presentation of the OVA(323......-339) immunodominant peptide to the I-Ad-restricted T cell hybridomas specific for it. Prepulsing experiments demonstrated that the PMR peptides were interacting with the APC and not with the T cell hybridomas. These observations were confirmed and extended by the demonstration that the alpha k-1 and alpha k-3...

Monoclonal antibodies against a synthetic peptide from human immunodeficiency virus type 1 Nef protein

DEFF Research Database (Denmark)

Steinaa, L; Wulff, A M; Saermark, T

1994-01-01

Monoclonal antibodies against a synthetic peptide (aa 138-152) from HIV-1 Nef protein were produced and characterized. Three hybridoma lines producing monoclonal antibodies (MAbs) against the synthetic peptide were generated by fusion between P3-X63 Ag8.653 myeloma cells and BALB/c splenocytes from...... mice immunized with the synthetic peptide coupled to keyhole limpet hemocyanin (KLH). The hybridomas were screened and selected by ELISA with the peptide coupled to bovine serum albumin (BSA) immobilized to the polystyrene surface and specificity for the peptide was confirmed by competitive ELISA...... with the peptide free in solution. The reactions of the MAbs with a 5-aa motif (WCYKL) included in the sequence were examined with synthetic peptides and two of the MAbs reacted with the motif. The recognitions of recombinant full-length Nef protein were also tested. One MAb reacted with the protein in both ELISA...

Rates of star formation

International Nuclear Information System (INIS)

Larson, R.B.

1977-01-01

It is illustrated that a theoretical understanding of the formation and evolution of galaxies depends on an understanding of star formation, and especially of the factors influencing the rate of star formation. Some of the theoretical problems of star formation in galaxies, some approaches that have been considered in models of galaxy evolution, and some possible observational tests that may help to clarify which processes or models are most relevant are reviewed. The material is presented under the following headings: power-law models for star formation, star formation processes (conditions required, ways of achieving these conditions), observational indications and tests, and measures of star formation rates in galaxies. 49 references

Exploring Opponent Formats

DEFF Research Database (Denmark)

Jensen, Mads Møller; Rasmussen, Majken; Grønbæk, Kaj

2013-01-01

of how the opponent format and relationships impact a game are almost absent in current research. Thus, this paper aims to elucidate how the perception of a competition differs, depending on the opponent format, by presenting a game mechanic framework. The paper furthermore presents an interactive...... football-training platform, as well as games designed to explore the different opponent formats. The games are qualitatively evaluated to illuminate the qualities of and distinctions between different types of opponent formats, proposed by the framework terminology....

ENDF/B format

International Nuclear Information System (INIS)

Khalil, M.A.; Lemmel, H.D.

1986-09-01

This document is a brief user's description of the format of ENDF/B. This format, originally designed for the US Evaluated Nuclear Data File, is recommended for international use. This summary is an aid to customers of the IAEA Nuclear Data Section when receiving data retrievals in ENDF/B format. For more detailed information the report BNL-NCS-50496 (ENDF 102) should be consulted. An Appendix to the present document gives a summary of the format differences between ENDF/B-4 and ENDF/B-5. (author)

Modeling single cell antibody excretion on a biosensor

NARCIS (Netherlands)

Stojanovic, Ivan; Baumgartner, W.; van der Velden, T.J.G.; Terstappen, Leonardus Wendelinus Mathias Marie; Schasfoort, Richardus B.M.

2016-01-01

We simulated, using Comsol Multiphysics, the excretion of antibodies by single hybridoma cells and their subsequent binding on a surface plasmon resonance imaging (SPRi) sensor. The purpose was to confirm that SPRi is suitable to accurately quantify antibody (anti-EpCAM) excretion. The model showed

The Gas-Phase Formation of Methyl Formate in Hot Molecular Cores

Science.gov (United States)

Horn, Anne; Møllendal, Harald; Sekiguchi, Osamu; Uggerud, Einar; Roberts, Helen; Herbst, Eric; Viggiano, A. A.; Fridgen, Travis D.

2004-08-01

Methyl formate, HCOOCH3, is a well-known interstellar molecule prominent in the spectra of hot molecular cores. The current view of its formation is that it occurs in the gas phase from precursor methanol, which is synthesized on the surfaces of grain mantles during a previous colder era and evaporates while temperatures increase during the process of high-mass star formation. The specific reaction sequence thought to form methyl formate, the ion-molecule reaction between protonated methanol and formaldehyde followed by dissociative recombination of the protonated ion [HCO(H)OCH3]+, has not been studied in detail in the laboratory. We present here the results of both a quantum chemical study of the ion-molecule reaction between [CH3OH2]+ and H2CO as well as new experimental work on the system. In addition, we report theoretical and experimental studies for a variety of other possible gas-phase reactions leading to ion precursors of methyl formate. The studied chemical processes leading to methyl formate are included in a chemical model of hot cores. Our results show that none of these gas-phase processes produces enough methyl formate to explain its observed abundance.

Free-format RPG IV the express guide to learning free format

CERN Document Server

Martin, Jim

2015-01-01

Focusing strictly on teaching free-format RPG programming methods, this book will help programmers wishing to upgrade their skills   This how-to guide offers a concise and thorough introduction to the increased productivity, better readability, and easier program maintenance that comes with the free-format style of programming in RPG IV. Although free-format information is available in IBM manuals, it is not separated from everything else, requiring hours of tedious research to track down the information needed. This book provides everything you need to know to write RPG IV in the free-format

Digital Forensics Formats: Seeking a Digital Preservation Storage Container Format for Web Archiving

Directory of Open Access Journals (Sweden)

Yunhyong Kim

2012-12-01

Full Text Available In this paper we discuss archival storage container formats from the point of view of digital curation and preservation, an aspect of preservation overlooked by most other studies. Considering established approaches to data management as our jumping off point, we selected seven container format attributes that are core to the long term accessibility of digital materials. We have labeled these core preservation attributes. These attributes are then used as evaluation criteria to compare storage container formats belonging to five common categories: formats for archiving selected content (e.g. tar, WARC, disk image formats that capture data for recovery or installation (partimage, dd raw image, these two types combined with a selected compression algorithm (e.g. tar+gzip, formats that combine packing and compression (e.g. 7-zip, and forensic file formats for data analysis in criminal investigations (e.g. aff – Advanced Forensic File format. We present a general discussion of the storage container format landscape in terms of the attributes we discuss, and make a direct comparison between the three most promising archival formats: tar, WARC, and aff. We conclude by suggesting the next steps to take the research forward and to validate the observations we have made.

A sensitive chain specific radioimmunoassay for human immunoglobulins using monoclonal antibodies

International Nuclear Information System (INIS)

Sikora, K.; Alderson, T.St.J.; Ellis, J.

1983-01-01

A sensitive radioimmunoassay is described for human immunoglobulins. This solid-phase assay uses commercially available monoclonal antibodies and is specific for different Ig chain types. Levels of less than 20 ng/ml Ig are detectable. The assay is suitable for the analysis of human hybridoma supernatants. (Auth.)

Main: PPD101 [AT Atlas

Lifescience Database Archive (English)

Full Text Available PPD101 PPD1 Development of novel affinity tag system for the high-quality productio...uantification, purification and tag removal for a variety of proteins. MPB3|MPB4 Protein Sci. (2008)|Hybridoma. (2008)|J Proteomics. (2010) 18787202|20566373|18847346 PPD101.csml ...

Sensitive chain specific radioimmunoassay for human immunoglobulins using monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Sikora, K; Alderson, T St.J.; Ellis, J [Ludwig Institute for Cancer Research, Cambridge (UK)

1983-02-25

A sensitive radioimmunoassay is described for human immunoglobulins. This solid-phase assay uses commercially available monoclonal antibodies and is specific for different Ig chain types. Levels of less than 20 ng/ml Ig are detectable. The assay is suitable for the analysis of human hybridoma supernatants.

Connecting the Cosmic Star Formation Rate with the Local Star Formation

Science.gov (United States)

Gribel, Carolina; Miranda, Oswaldo D.; Williams Vilas-Boas, José

2017-11-01

We present a model that unifies the cosmic star formation rate (CSFR), obtained through the hierarchical structure formation scenario, with the (Galactic) local star formation rate (SFR). It is possible to use the SFR to generate a CSFR mapping through the density probability distribution functions commonly used to study the role of turbulence in the star-forming regions of the Galaxy. We obtain a consistent mapping from redshift z˜ 20 up to the present (z = 0). Our results show that the turbulence exhibits a dual character, providing high values for the star formation efficiency ( ˜ 0.32) in the redshift interval z˜ 3.5{--}20 and reducing its value to =0.021 at z = 0. The value of the Mach number ({{ M }}{crit}), from which rapidly decreases, is dependent on both the polytropic index (Γ) and the minimum density contrast of the gas. We also derive Larson’s first law associated with the velocity dispersion ( ) in the local star formation regions. Our model shows good agreement with Larson’s law in the ˜ 10{--}50 {pc} range, providing typical temperatures {T}0˜ 10{--}80 {{K}} for the gas associated with star formation. As a consequence, dark matter halos of great mass could contain a number of halos of much smaller mass, and be able to form structures similar to globular clusters. Thus, Larson’s law emerges as a result of the very formation of large-scale structures, which in turn would allow the formation of galactic systems, including our Galaxy.

Formative assessment : Enriching teaching and learning with formative assesment

NARCIS (Netherlands)

van Diggelen, M.R.; Morgan, C.M.; Funk, M.; Bruns, M.

2016-01-01

Formative assessment is a valuable aspect in teaching and learning, and is proven to be an e ective learning method. There is evidence that adding formative assessment to your teaching increases students’ learning results (Black and William, 1998), but in practice many of the possibilities are left

[Monoclonal antibodies ICO-02 to blast cell antigens in patients with chronic myeloleukemia in blast crisis].

Science.gov (United States)

Baryshnikov, A Iu

1984-01-01

Mice were immunized with blood cells of a patient with chronic granulocytic leukemia, and their cells were subsequently used for the preparation of hybridoma ICO-02. This hybridoma is continuously producing monoclonal antibodies which reacted with cells in 4 out of 13 patients with blastic crisis of chronic granulocytic leukemia and in 6 out of 38 patients with acute lymphoblastic leukemia. Antibodies reacted with blast cells in 2 out of 3 patients with undifferentiated blastic crisis of chronic myelocytic leukemia and in 2 out of 5 patients with lymphoid variant of blastic crisis of chronic granulocytic leukemia. Cells of 6 patients with acute lymphoblastic leukemia which reacted with the monoclonal antibodies had immunological markers of T lymphocytes bone-marrow precursors. Monoclonal antibodies did not react with cells of blood and bone marrow from healthy people and from patients with chronic lymphocytic leukemia, acute myeloblastic leukemia, acute myelomonocytic leukemia, acute monoblastic leukemia and lymphosarcoma.

Development and characterization of novel chimeric monoclonal antibodies for broad spectrum neutralization of rabies virus.

Directory of Open Access Journals (Sweden)

Pan Kyeom Kim

Full Text Available Current post-exposure prophylaxis for rabies virus infection has several limitations in terms of supply, cost, safety, and efficacy. Attempts to replace human or equine rabies immune globulins (HRIG or ERIG have been made by several companies and institutes. We developed potent monoclonal antibodies to neutralize a broad spectrum of rabies viruses by screening hybridomas received from the U.S. Centers for Disease Control and Prevention (CDC. Two kinds of chimeric human antibodies (chimeric #7 and #17 were constructed by cloning the variable regions from selected hybridomas and the constant region of a human antibody. Two antibodies were bound to antigenic site III and I/IV, respectively, and were able to neutralize 51 field isolates of rabies virus that were isolated at different times and places such as Asia, Africa, North America, South America, and Australia. These two antibodies neutralize rabies viruses with high efficacy in an in vivo test using Syrian hamster and mouse models and show low risk for adverse immunogenicity.

Cross-reacting and heterospecific monoclonal antibodies produced against arabis mosaic nepovirus.

Science.gov (United States)

Frison, E A; Stace-Smith, R

1992-10-01

Monoclonal antibodies (MAbs) were produced against arabis mosaic nepovirus (AMV). A hybridoma screening procedure was applied which involved the testing of culture supernatants, before the hybridomas were cloned to single cell lines, for their reaction with eight nepoviruses [AMV, cherry leafroll virus (CLRV), grapevine fanleaf virus (GFLV), peach rosette mosaic virus, raspberry ringspot virus (RRSV), tobacco ringspot virus, tomato black ring virus (TBRV) and tomato ringspot virus]. In addition to AMV-specific MAbs, this screening technique has allowed the selection of two cross-reacting MAbs: one reacting with AMV and GFLV, and one reacting with AMV and RRSV. This is the first report of MAbs cross-reacting with these nepoviruses. In addition, five heterospecific MAbs (HS-MAbs) could be selected: two reacting with RRSV, two with CLRV and one with TBRV. The usefulness of the screening technique that was applied for the selection of cross-reacting MAbs and HS-MAbs, and the potential use of such antibodies are discussed.

Development and characterization of novel chimeric monoclonal antibodies for broad spectrum neutralization of rabies virus.

Science.gov (United States)

Kim, Pan Kyeom; Keum, Sun Ju; Osinubi, Modupe O V; Franka, Richard; Shin, Ji Young; Park, Sang Tae; Kim, Man Su; Park, Mi Jung; Lee, Soo Young; Carson, William; Greenberg, Lauren; Yu, Pengcheng; Tao, Xiaoyan; Lihua, Wang; Tang, Qing; Liang, Guodong; Shampur, Madhusdana; Rupprecht, Charles E; Chang, Shin Jae

2017-01-01

Current post-exposure prophylaxis for rabies virus infection has several limitations in terms of supply, cost, safety, and efficacy. Attempts to replace human or equine rabies immune globulins (HRIG or ERIG) have been made by several companies and institutes. We developed potent monoclonal antibodies to neutralize a broad spectrum of rabies viruses by screening hybridomas received from the U.S. Centers for Disease Control and Prevention (CDC). Two kinds of chimeric human antibodies (chimeric #7 and #17) were constructed by cloning the variable regions from selected hybridomas and the constant region of a human antibody. Two antibodies were bound to antigenic site III and I/IV, respectively, and were able to neutralize 51 field isolates of rabies virus that were isolated at different times and places such as Asia, Africa, North America, South America, and Australia. These two antibodies neutralize rabies viruses with high efficacy in an in vivo test using Syrian hamster and mouse models and show low risk for adverse immunogenicity.

The development of methods for obtaining monoclonal antibody-producing cells

Directory of Open Access Journals (Sweden)

Michał Skowicki

2016-04-01

Full Text Available Monoclonal antibodies (mAbs are biomolecules of great scientific and practical significance. In contrast to polyclonal antibodies from immune sera, they are homogeneous and monospecific, since they are produced by hybridoma cells representing a clone arising from a single cell. The successful technology was described for the first time in 1975; the inventors were later awarded the Nobel Prize. Currently, mAbs are broadly used as a research tool, in diagnostics and medicine in particular for the treatment of cancer or in transplantology. About 47 therapeutics based on monoclonal antibodies are now available in the US and Europe, and the number is still growing. Production of monoclonal antibodies is a multistage, time-consuming and costly process. Growing demand for these molecules creates space for research focused on improvements in hybridoma technology. Lower costs, human labor, and time are important goals of these attempts. In this article, a brief review of current methods and their advances is given.

Cyclosporine A suppresses immunoglobulin G biosynthesis via inhibition of cyclophilin B in murine hybridomas and B cells.

Science.gov (United States)

Lee, Jisun; Choi, Tae Gyu; Ha, Joohun; Kim, Sung Soo

2012-01-01

Immunoglubulin G (IgG) is a major isotype of antibody, which is predominantly involved in immune response. The complete tetramer is needed to fold and assemble in endoplasmic reticulum (ER) prior to secretion from cells. Protein quality control guided by ER chaperons is most essential for full biological activity. Cyclophilin B (CypB) was initially identified as a high-affinity binding protein for the immunosuppressive drug Cyclosporine A (CsA). CsA suppresses organ rejection by halting productions of pro-inflammatory molecules in T cell and abolishes the enzymatic property of CypB that accelerates the folding of proteins by catalysing the isomerization of peptidyl-proline bonds in ER. Here, we reported that CsA significantly inhibited IgG biosynthesis at posttranslational level in antibody secreting cells. Moreover, CsA stimulated the extracellular secretion of CypB and induced ROS generation, leading to expressions of ER stress markers. In addition, the absence of intracellular CypB impaired the formation of ER multiprotein complex, which is most important for resisting ER stress. Interestingly, CsA interrupted IgG folding via occupying the PPIase domain of CypB in ER. Eventually, unfolded IgG is degraded via Herp-dependent ERAD pathway. Furthermore, IgG biosynthesis was really abrogated by inhibition of CypB in primary B cells. We established for the first time the immunosuppressive effect of CsA on B cells. Conclusively, the combined results of the current study suggest that CypB is a pivotal molecule for IgG biosynthesis in ER quality control. Copyright © 2011 Elsevier B.V. All rights reserved.

THE SPECIAL STATUS OF EXOGENOUS WORD-FORMATION WITHIN THE GERMAN WORD-FORMATION SYSTEM

Directory of Open Access Journals (Sweden)

Zhilyuk Sergey Aleksandrovich

2014-06-01

Full Text Available The article presents the properties of exogenous word-formation system taking into account the existence of two word-formation systems in modern German. On the basis of foreign research which reveal modern trends in German word-formation connected with the internationalization and the development of new European Latin language. The author defines key features of exogenous word-formation, i.e. foreign origin of wordformation units, unmotivated units, unmotivated interchange in base and affixes as well as limited distribution rules in combination with German word-formation. The article analyzes various approaches to word-division, as well as motivated and unmotivated interchange of consonants in bases and in affixes. Unmotivated interchange showcases a special status of the exogenous word-formation within German. Another item covered by the article is the issue of confix. The article has opinions of researchers about correctness of its separation and a list of its features. The author presents his definition of confix: a confix is a bound exogenous word-formation unit with a certain lexical and semantic meaning and joining other units directly or indirectly (through linking morpheme -o-, which is able to make a base. Moreover, some confixes are able to participate at word-combination and have unlimited distribution. So far, confix showcases the integration of exogenous word-formation and traditional German word-formation. The research proves the special status of exogenous word-formation in German. Its results can be used as a base for further analysis of co-existing word-formation systems in German and determination of their characteristic features.

Comet formation

Science.gov (United States)

Blum, J.

2014-07-01

There has been vast progress in our understanding of planetesimal formation over the past decades, owing to a number of laboratory experiments as well as to refined models of dust and ice agglomeration in protoplanetary disks. Coagulation rapidly forms cm-sized ''pebbles'' by direct sticking in collisions at low velocities (Güttler et al. 2010; Zsom et al. 2010). For the further growth, two model approaches are currently being discussed: (1) Local concentration of pebbles in nebular instabilities until gravitational instability occurs (Johansen et al. 2007). (2) A competition between fragmentation and mass transfer in collisions among the dusty bodies, in which a few ''lucky winners'' make it to planetesimal sizes (Windmark et al. 2012a,b; Garaud et al. 2013). Predictions of the physical properties of the resulting bodies in both models allow a distinction of the two formation scenarios of planetesimals. In particular, the tensile strength (i.e, the inner cohesion) of the planetesimals differ widely between the two models (Skorov & Blum 2012; Blum et al. 2014). While model (1) predicts tensile strengths on the order of ˜ 1 Pa, model (2) results in rather compactified dusty bodies with tensile strengths in the kPa regime. If comets are km-sized survivors of the planetesimal-formation era, they should in principle hold the secret of their formation process. Water ice is the prime volatile responsible for the activity of comets. Thermophysical models of the heat and mass transport close to the comet-nucleus surface predict water-ice sublimation temperatures that relate to maximum sublimation pressures well below the kPa regime predicted for formation scenario (2). Model (1), however, is in agreement with the observed dust and gas activity of comets. Thus, a formation scenario for cometesimals involving gravitational instability is favored (Blum et al. 2014).

Cement Formation

DEFF Research Database (Denmark)

Telschow, Samira; Jappe Frandsen, Flemming; Theisen, Kirsten

2012-01-01

Cement production has been subject to several technological changes, each of which requires detailed knowledge about the high multiplicity of processes, especially the high temperature process involved in the rotary kiln. This article gives an introduction to the topic of cement, including...... an overview of cement production, selected cement properties, and clinker phase relations. An extended summary of laboratory-scale investigations on clinkerization reactions, the most important reactions in cement production, is provided. Clinker formations by solid state reactions, solid−liquid and liquid......−liquid reactions are discussed, as are the influences of particles sizes on clinker phase formation. Furthermore, a mechanism for clinker phase formation in an industrial rotary kiln reactor is outlined....

Analysis of antigenic relationships among influenza virus strains using a taxonomic cluster procedure. Comparison of three kinds of antibody preparations.

NARCIS (Netherlands)

T.F. Weijers; A.D.M.E. Osterhaus (Albert); W.E.Ph. Beyer (Walter); J.A.A.M. van Asten (Jack); F.M. de Ronde-Verloop; K. Bijlsma (Klaas); J.C. de Jong (Jan)

1985-01-01

textabstractHemagglutination inhibiting (HI) monoclonal antibody preparations (MA) were raised against six influenza A (H3N2) strains from the period 1977-1982. Twenty-three hybridomas were selected and titrated in HI assays against these strains and against 18 influenza A (H3N2) viruses isolated in

Radioimaging of human mammary carcinoma xenografts in nude mice with a new monoclonal antibody

International Nuclear Information System (INIS)

Senekowitsch, R.; Bode, W.; Kriegel, H.; Reidel, G.; Pabst, H.W.

1986-01-01

A female Wistar rat aged 33 days was immunized by repeated intraperitoneal injections of a cell suspension of mammary carcinoma for eight months. Spleen cells of the immunized rat were then fused with X63-Ag8.653, a mouse myeloma line. Hybridoma supernatants were screened by ELISA using cells of mammary carcinoma (MaCa) as target cells. Initially 72 hybridomas showed positive response with MaCa cells, but no cross-reaction with normal mammary tissue was seen. Clone Ma 10-11 was chosen for its stable growth in vitro and in ascitic fluid. Monoclonal antibody obtained from ascitic fluid induced by intraperitoneal injection of 10 7 hybridoma cell into BALB/c-nu/nu mice was separated from albumin and transferrin. After separation only one band positioned at 155000 MW on SDS-PAGE slabs was detected. Radiolabeling with 131 I was achieved with the Iodogen method, the efficiency of labeling was 88%. 1.85 MBq of the intact labeled rat antibody were injected into nude mice xenografted with human mammary carcinoma and scintigrams were obtained every 48 hours p.i. up to 15 days. Scintigraphic images permitted tumor detection at 3 days p.i., but good tumor localization needed 8 days p.i.. The tumor-to-blood ratios calculated after dissection of tumor-bearing mice in groups of 3 increased from 0.97 at day 3 to 3 at day 15 p.i.. No uptake of the antibody in other organs was found. The half-life of the whole body clearance of the rat immunoglobulin was 36 h. This is significantly shorter than the half-life found for mouse immunoglobulin in nude mice. (Author)

Theory of aurora formation

International Nuclear Information System (INIS)

Hasegawa, Akira.

1975-04-01

A new theory of aurora formation is presented based on Alfven wave-electron interaction. The theory explains consistently 1) the electron acceleration process, 2) the formation of auroral layers and 3) the long wave formation in the longitudinal direction. (auth.)

THE SPECIAL STATUS OF EXOGENOUS WORD-FORMATION WITHIN THE GERMAN WORD-FORMATION SYSTEM

OpenAIRE

Zhilyuk Sergey Aleksandrovich

2014-01-01

The article presents the properties of exogenous word-formation system taking into account the existence of two word-formation systems in modern German. On the basis of foreign research which reveal modern trends in German word-formation connected with the internationalization and the development of new European Latin language. The author defines key features of exogenous word-formation, i.e. foreign origin of wordformation units, unmotivated units, unmotivated interchange in base and affixes...

Method and cell lines for the production of monoclonal antibodies to human glycophorin A

Science.gov (United States)

Bigbee, W.L.; Fong, S.S.N.; Jensen, R.H.; Vanderlaan, M.

Cloned mouse hybridoma cell lines have been established which continuously produce antibodies that differentiate between the M and N forms of human glycophorin A. These antibodies have potential application as human blood group reagents, as markers for terminally differentiated erythroid cells and as immunofluorescent labels of somatically variant human erythrocytes.

Development of New Approaches for Breast Cancer Therapy and Diagnosis Based on Angiogenesis

Science.gov (United States)

1997-10-01

Immune complexes were incubated for two hours at 4°C with rabbit anti-mouse IgG and then were precipitated upon addition of proteinA - Sepharose 4B...from the cloned hybridomas. These studies are just getting underway. CONCLUSIONS The main objective of this grant is identify specific molecular

Star formation

International Nuclear Information System (INIS)

Woodward, P.R.

1978-01-01

Theoretical models of star formation are discussed beginning with the earliest stages and ending in the formation of rotating, self-gravitating disks or rings. First a model of the implosion of very diffuse gas clouds is presented which relies upon a shock at the edge of a galactic spiral arm to drive the implosion. Second, models are presented for the formation of a second generation of massive stars in such a cloud once a first generation has formed. These models rely on the ionizing radiation from massive stars or on the supernova shocks produced when these stars explode. Finally, calculations of the gravitational collapse of rotating clouds are discussed with special focus on the question of whether rotating disks or rings are the result of such a collapse. 65 references

Vascular lumen formation.

Science.gov (United States)

Lammert, Eckhard; Axnick, Jennifer

2012-04-01

The vascular system developed early in evolution. It is required in large multicellular organisms for the transport of nutrients, oxygen, and waste products to and from tissues. The vascular system is composed of hollow tubes, which have a high level of complexity in vertebrates. Vasculogenesis describes the de novo formation of blood vessels, e.g., aorta formation in vertebrate embryogenesis. In contrast, angiogenesis is the formation of blood vessels from preexisting ones, e.g., sprouting of intersomitic blood vessels from the aorta. Importantly, the lumen of all blood vessels in vertebrates is lined and formed by endothelial cells. In both vasculogenesis and angiogenesis, lumen formation takes place in a cord of endothelial cells. It involves a complex molecular mechanism composed of endothelial cell repulsion at the cell-cell contacts within the endothelial cell cords, junctional rearrangement, and endothelial cell shape change. As the vascular system also participates in the course of many diseases, such as cancer, stroke, and myocardial infarction, it is important to understand and make use of the molecular mechanisms of blood vessel formation to better understand and manipulate the pathomechanisms involved.

Isothermal Martensite Formation

DEFF Research Database (Denmark)

Villa, Matteo

Isothermal (i.e. time dependent) martensite formation in steel was first observed in the 40ies of the XXth century and is still treated as an anomaly in the description of martensite formation which is considered as a-thermal (i.e. independent of time). Recently, the clarification of the mechanism...... of lattice strains provided fundamental information on the state of stress in the material and clarified the role of the strain energy on martensite formation. Electron backscatter diffraction revealed that the microstructure of the material and the morphology of martensite were independent on the cooling...... leading to isothermal kinetics acquired new practical relevance because of the identification of isothermal martensite formation as the most likely process responsible for enhanced performances of sub-zero Celsius treated high carbon steel products. In the present work, different iron based alloys...

Data format translation routines

International Nuclear Information System (INIS)

Burris, R.D.

1981-02-01

To enable the effective connection of several dissimilar computers into a network, modification of the data being passed from one computer to another may become necessary. This document describes a package of routines which permit the translation of data in PDP-8 formats to PDP-11 or DECsystem-10 formats or from PDP-11 format to DECsystem-10 format. Additional routines are described which permit the effective use of the translation routines in the environment of the Fusion Energy Division (FED) network and the Elmo Bumpy Torus (EBT) data base

From Sermon Formation to Preacher Formation

DEFF Research Database (Denmark)

Gaarden, Marianne

2016-01-01

today is less about exercising the authority of an office and more about embodying authenticity. I argue that traditional homiletic education can benefit from implementing a learner-centered approach to teaching moving from sermon formation towards preacher formation, in order to develop and train...... preachers. This involves a learning strategy to ministry where theological skills, pastoral competences, and own personality are interwoven. Teaching here means facilitating a room of learning where teacher’s power and control is reduced, allowing the preacher to reflect upon own practice without being...... judged, evaluated, or critiqued. In this paper, I explain how a learner-centered approach to education works in practice and show how pastors experience the teaching method and the congregations’ positive response to their improvements. I shall present the results of a focus-group interview with pastors...

Feedback in formative OSCEs: comparison between direct observation and video-based formats

Science.gov (United States)

Junod Perron, Noëlle; Louis-Simonet, Martine; Cerutti, Bernard; Pfarrwaller, Eva; Sommer, Johanna; Nendaz, Mathieu

2016-01-01

Introduction Medical students at the Faculty of Medicine, University of Geneva, Switzerland, have the opportunity to practice clinical skills with simulated patients during formative sessions in preparation for clerkships. These sessions are given in two formats: 1) direct observation of an encounter followed by verbal feedback (direct feedback) and 2) subsequent review of the videotaped encounter by both student and supervisor (video-based feedback). The aim of the study was to evaluate whether content and process of feedback differed between both formats. Methods In 2013, all second- and third-year medical students and clinical supervisors involved in formative sessions were asked to take part in the study. A sample of audiotaped feedback sessions involving supervisors who gave feedback in both formats were analyzed (content and process of the feedback) using a 21-item feedback scale. Results Forty-eight audiotaped feedback sessions involving 12 supervisors were analyzed (2 direct and 2 video-based sessions per supervisor). When adjusted for the length of feedback, there were significant differences in terms of content and process between both formats; the number of communication skills and clinical reasoning items addressed were higher in the video-based format (11.29 vs. 7.71, p=0.002 and 3.71 vs. 2.04, p=0.010, respectively). Supervisors engaged students more actively during the video-based sessions than during direct feedback sessions (self-assessment: 4.00 vs. 3.17, p=0.007; active problem-solving: 3.92 vs. 3.42, p=0.009). Students made similar observations and tended to consider that the video feedback was more useful for improving some clinical skills. Conclusion Video-based feedback facilitates discussion of clinical reasoning, communication, and professionalism issues while at the same time actively engaging students. Different time and conceptual frameworks may explain observed differences. The choice of feedback format should depend on the educational

Feedback in formative OSCEs: comparison between direct observation and video-based formats

Directory of Open Access Journals (Sweden)

Noëlle Junod Perron

2016-11-01

Full Text Available Introduction: Medical students at the Faculty of Medicine, University of Geneva, Switzerland, have the opportunity to practice clinical skills with simulated patients during formative sessions in preparation for clerkships. These sessions are given in two formats: 1 direct observation of an encounter followed by verbal feedback (direct feedback and 2 subsequent review of the videotaped encounter by both student and supervisor (video-based feedback. The aim of the study was to evaluate whether content and process of feedback differed between both formats. Methods: In 2013, all second- and third-year medical students and clinical supervisors involved in formative sessions were asked to take part in the study. A sample of audiotaped feedback sessions involving supervisors who gave feedback in both formats were analyzed (content and process of the feedback using a 21-item feedback scale. Results: Forty-eight audiotaped feedback sessions involving 12 supervisors were analyzed (2 direct and 2 video-based sessions per supervisor. When adjusted for the length of feedback, there were significant differences in terms of content and process between both formats; the number of communication skills and clinical reasoning items addressed were higher in the video-based format (11.29 vs. 7.71, p=0.002 and 3.71 vs. 2.04, p=0.010, respectively. Supervisors engaged students more actively during the video-based sessions than during direct feedback sessions (self-assessment: 4.00 vs. 3.17, p=0.007; active problem-solving: 3.92 vs. 3.42, p=0.009. Students made similar observations and tended to consider that the video feedback was more useful for improving some clinical skills. Conclusion: Video-based feedback facilitates discussion of clinical reasoning, communication, and professionalism issues while at the same time actively engaging students. Different time and conceptual frameworks may explain observed differences. The choice of feedback format should depend on

Galaxy Formation

DEFF Research Database (Denmark)

Sparre, Martin

Galaxy formation is an enormously complex discipline due to the many physical processes that play a role in shaping galaxies. The objective of this thesis is to study galaxy formation with two different approaches: First, numerical simulations are used to study the structure of dark matter and how...... galaxies form stars throughout the history of the Universe, and secondly it is shown that observations of gamma-ray bursts (GRBs) can be used to probe galaxies with active star formation in the early Universe. A conclusion from the hydrodynamical simulations is that the galaxies from the stateof...... is important, since it helps constraining chemical evolution models at high redshift. A new project studying how the population of galaxies hosting GRBs relate to other galaxy population is outlined in the conclusion of this thesis. The core of this project will be to quantify how the stellar mass function...

Reconsidering formative measurement.

Science.gov (United States)

Howell, Roy D; Breivik, Einar; Wilcox, James B

2007-06-01

The relationship between observable responses and the latent constructs they are purported to measure has received considerable attention recently, with particular focus on what has become known as formative measurement. This alternative to reflective measurement in the area of theory-testing research is examined in the context of the potential for interpretational confounding and a construct's ability to function as a point variable within a larger model. Although these issues have been addressed in the traditional reflective measurement context, the authors suggest that they are particularly relevant in evaluating formative measurement models. On the basis of this analysis, the authors conclude that formative measurement is not an equally attractive alternative to reflective measurement and that whenever possible, in developing new measures or choosing among alternative existing measures, researchers should opt for reflective measurement. In addition, the authors provide guidelines for researchers dealing with existing formative measures. Copyright 2007 APA, all rights reserved.

Usage Record Format Recommendation

CERN Document Server

Nilsen, J.K.; Muller-Pfeerkorn, R

2013-01-01

For resources to be shared, sites must be able to exchange basic accounting and usage data in a common format. This document describes a common format which enables the exchange of basic accounting and usage data from different resources. This record format is intended to facilitate the sharing of usage information, particularly in the area of the accounting of jobs, computing, memory, storage and cloud usage but with a structure that allows an easy extension to other resources. This document describes the Usage Record components both in natural language form and annotated XML. This document does not address how these records should be used, nor does it attempt to dictate the format in which the accounting records are stored. Instead, it denes a common exchange format. Furthermore, nothing is said regarding the communication mechanisms employed to exchange the records, i.e. transport layer, framing, authentication, integrity, etc.

Stages of ores formation

International Nuclear Information System (INIS)

Khasanov, A.Kh.

1988-01-01

Deposit formation (especially endogenous) is the complicated, multi-stage and long process. Establishment of deposit formation succession, age-specific correlations of minerals and aggregates have a high importance at solving genetic questions. Studying of minerals correlations and mineral aggregates, succession of their crystallization and other observations let restore the history of deposit formation, pick up in it different on duration and physical and chemical conditions stages

Production of recombinant Ig molecules from antigen-selected single B cells and restricted usage of Ig-gene segments by anti-D antibodies

NARCIS (Netherlands)

Dohmen, Serge E.; Mulder, Arend; Verhagen, Onno J. H. M.; Eijsink, Chantal; Franke-van Dijk, Marry E. I.; van der Schoot, C. Ellen

2005-01-01

The Ig-genes of the heavy chains in anti-D-specific hybridomas and Fab/scFv-fragments selected from phage-display libraries are restricted to a group of closely related genes (IGHV3s genes). We analyzed the Ig-gene repertoire in anti-D-specific B cells of two hyperimmunized donors using a completely

Antibodies directed against monomorphic and evolutionary conserved self epitopes may be generated in 'knock-out' mice. Development of monoclonal antibodies directed against monomorphic MHC class I determinants

DEFF Research Database (Denmark)

Claesson, M H; Endel, B; Ulrik, J

1994-01-01

Beta-2 microglobulin (beta 2m) gene 'knock-out' mice (C1D) were primed with purified H-2Kb and H-2Db molecules and spleen cells from immunized mice were used to generate monoclonal antibody secreting B-cell hybridomas. Approximately 0.2% of the Ig-secreting primary microcultures contained H-2b...

Television Format As a Site of Cultural Negotiation: Studying the Structures, Agencies and Practices of Format Adaptation

NARCIS (Netherlands)

Keinonen, Heidi

2016-01-01

abstractDespite the growing number of publications on television formats, specific theorisations regarding formats and format adaptation, in particular, are still rare. In this article, I introduce a synthesizing approach for studying format appropriation. Drawing on format study, media industry

Monoclonal antibodies from rats immunized with fragment D of human fibrinogen

International Nuclear Information System (INIS)

Kennel, S.J.; Chen, J.P.; Lankford, P.K.; Foote, L.J.

1981-01-01

Fischer rats were immunized with fragment D (Fg-D) of human fibrinogen (Fg) to obtain antibody specific for neoantigens unique to this molecule. Absorption of serum with whole Fg indicated that some of the antibody produced reacted preferentially with Fg-D. Hybridoma cultures were prepared by fusion of immune rat spleen cells with mouse myeloma P3-X63-Ag8. Monoclonal antibodies obtained from these cultures fell into two classes: (a) Those reacting equally well with Fg and Fg-D. (b) Those reacting preferentially but not absolutely wth Fg-D. Antibody from hybridoma 104-14, a member of the first group had an affinity for Fg-D of 1.5 x 10 9 M -1 while antibodies from 106-59 and 106-71 (group 2) demonstrated much lower affinities of 1.0 x 10 7 and 4.7 x 10 6 M -1 , respectively. The cross reactivity of antibodies in the second group indicated that they react with protein conformations that are altered during production of Fg-D from Fg

Monoclonal Antibody Production against Human Spermatozoal Surface Antigens

Directory of Open Access Journals (Sweden)

M Jedi-Tehrani

2005-10-01

Full Text Available Introduction: As monoclonal antibodies are potential tools for characterization of soluble or cellular surface antigens, use of these proteins has always been considered in infertility and reproduction research. Therefore, in this study, monoclonal antibodies against human sperm surface antigens were produced. Material and Methods: To produce specific clones against human sperm surface antigens, proteins were extracted using solubilization methods. Balb/c mice were immunized intraperitoneally with the proteins using complete Freund’s adjuvant in the first injection and incomplete Adjuvant in the following booster injections. Hybridoma cells producing ASA were cloned by limiting dilution. Results: Five stable ASA producing hybridoma clones were achieved and their antibody isotypes were determined by ELISA. All the isotypes were of IgG class. Their cross reactivity with rat and mice spermatozoa was examined but they did not have any cross reactivity. Conclusion: The produced antibodies can be used in further studies to characterize and evaluate each of the antigens present on human sperm surface and determining their role in fertilization.

Blistering and bubble formation

International Nuclear Information System (INIS)

Roth, J.

1976-01-01

Blister formation in metals has been observed during bombardment with inert-gas ions in the energy range between 1 and 2000 keV at doses of about 10 17 to 10 19 cm -2 . The changes in surface topography and the erosion yields were mainly studied in the scanning electron microscope (SEM). Additionally the release of the implanted gas during blister formation was observed. Recently measurements on single crystals were performed determining simultaneously the implantation profile, the total amount of trapped ions, the depth distribution of the induced lattice damage and the thickness of the covers of the blisters. In several stages of the formation process of blisters the implanted layer was observed in the transmission electron microscope (TEM) showing the formation of gas bubbles. Using the results of all these measurements in this review an attempt is made to develop a model of blister formation combining the effects of hydrostatic pressure in the gas bubbles and lateral stress due to volume swelling. (author)

Fracturing formations in wells

Energy Technology Data Exchange (ETDEWEB)

Daroza, R A

1964-05-15

This well stimulation method comprises introducing through the well bore a low-penetrating, dilatant fluid, and subjecting the fluid to sufficient pressure to produce fractures in the formation. The fluid is permitted to remain in contact with the formation so as to become diluted by the formation fluids, and thereby lose its properties of dilatancy. Also, a penetrating fluid, containing a propping agent suspended therein, in introduced into contact with the fractures at a pressure substantially reduced with respect to that pressure which would have been required, prior to the fracturing operation performed using the low-penetrating dilatant fluid. The propping agent is deposited within the fractures, and thereafter, fluid production is resumed from the fractured formation. (2 claims)

'TV Format Protection through Marketing Strategies?'

OpenAIRE

Singh, Sukhpreet

2008-01-01

Commercially successful programme ideas are often imitated or adapted. Television formats, in particular, are routinely copied. Starting from radio formats in the 1950s to game shows and reality programme formats of today, producers have accused others of “stealing”. Although formats constitute one of the most important exports for British TV producers, there is still no certainty about the legal protection of TV formats from copycat versions. Since TV formats fail to fall neatly within the d...

Dislocation processes in quasicrystals-Kink-pair formation control or jog-pair formation control

International Nuclear Information System (INIS)

Takeuchi, Shin

2005-01-01

A computer simulation of dislocation in a model quasiperiodic lattice indicates that the dislocation feels a large Peierls potential when oriented in particular directions. For a dislocation with a high Peierls potential, the glide velocity and the climb velocity of the dislocation can be described almost in parallel in terms of the kink-pair formation followed by kink motion and the jog-pair formation followed by jog motion, respectively. The activation enthalpy of the kink-pair formation is the sum of the kink-pair formation enthalpy and the atomic jump activation enthalpy, while the activation enthalpy of the jog-pair formation involves the jog-pair enthalpy and the self-diffusion enthalpy. Since the kink-pair energy can be considerably larger than the jog-pair energy, the climb velocity can be faster than the glide velocity, so that the plastic deformation of quasicrystals can be brought not by dislocation glide but by dislocation climb at high temperatures

Solubility studies of oxovanadium(V) formate and vanadyl formate in aqueous medium

International Nuclear Information System (INIS)

Tripathi, V.S.; Bairwa, K.K.; Naik, D.B.; Raje, N.H.; Bera, S.

2014-01-01

The solubility of oxovanadium(V) formate and vanadyl formate in aqueous medium has been determined. These compounds are important for preparation of strong reducing V(II) compounds which are used in stainless steel based nuclear power plants for decontamination

Monoclonal antibodies directed to human insulin-like growth factor I (IGF I)

International Nuclear Information System (INIS)

Laubli, U.K.; Baier, W.; Celio, M.R.; Binz, H.; Humbel, R.E.

1982-01-01

Mouse hybridomas secreting antibodies to human insulin-like growth factor I (IGF I) were produced by fusion of spleen cells of hyperimmunised mice with FO mouse-myeloma cells. Eight clones producing antibodies against human IGF I have been isolated, two of which have been characterised. One was used in a radioimmunoassay, the other for immunopurification of IGF. (Auth.)

Planet formation in Binaries

OpenAIRE

Thebault, Ph.; Haghighipour, N.

2014-01-01

Spurred by the discovery of numerous exoplanets in multiple systems, binaries have become in recent years one of the main topics in planet formation research. Numerous studies have investigated to what extent the presence of a stellar companion can affect the planet formation process. Such studies have implications that can reach beyond the sole context of binaries, as they allow to test certain aspects of the planet formation scenario by submitting them to extreme environments. We review her...

What Determines Star Formation Rates?

Science.gov (United States)

Evans, Neal John

2017-06-01

The relations between star formation and gas have received renewed attention. We combine studies on scales ranging from local (within 0.5 kpc) to distant galaxies to assess what factors contribute to star formation. These include studies of star forming regions in the Milky Way, the LMC, nearby galaxies with spatially resolved star formation, and integrated galaxy studies. We test whether total molecular gas or dense gas provides the best predictor of star formation rate. The star formation ``efficiency," defined as star formation rate divided by mass, spreads over a large range when the mass refers to molecular gas; the standard deviation of the log of the efficiency decreases by a factor of three when the mass of relatively dense molecular gas is used rather than the mass of all the molecular gas. We suggest ways to further develop the concept of "dense gas" to incorporate other factors, such as turbulence.

Package Formats for Preserved Digital Material

DEFF Research Database (Denmark)

Zierau, Eld

2012-01-01

This paper presents an investigation of the best suitable package formats for long term digital preservation. The choice of a package format for preservation is crucial for future access, thus a thorough analysis of choice is important. The investigation presented here covers setting up requireme......This paper presents an investigation of the best suitable package formats for long term digital preservation. The choice of a package format for preservation is crucial for future access, thus a thorough analysis of choice is important. The investigation presented here covers setting up...... requirements for package formats used for long term preserved digital material, and using these requirements as the basis for analysing a range of package formats. The result of the concrete investigation is that the WARC format is the package format best suited for the listed requirements. Fulfilling...

FORMATE-BASED FLUIDS: FORMULATION AND APPLICATION

Directory of Open Access Journals (Sweden)

Nediljka Gaurina-Međimurec

2008-12-01

Full Text Available Formate-based fluids has been successfully used in over hunders HPHT well operations since they introduced in field practice. They have many advantages when compared with conventional HPHT drilling and completion fluids such as: minimal formation damage, maintenance of additve properties at high temperatures, reduced hydraulic flow resistance, low potential for differential sticking, naturally lubricating, very low corrosion rates, biodegradable and pose little risk to the environment etc. Formate-based fluids can be applied during deep slim hole drilling, shale drilling, reservoir drilling, salt and gas hydrate formations drilling. The laboratory research was carried out to evaluate the rheological behavior of formate-based fluids as a function of temperature. Formate-based fluids were formulated using potassium formate brine, xanthan polymer, PAC, starch and calcium carbonate. Experimental results show that potassium formate improves the thermal stability of polymers.

Radiogeochemical features of hydrothermal metasomatic formations

International Nuclear Information System (INIS)

Plyushchev, E.V.; Ryabova, L.A.; Shatov, V.V.

1978-01-01

Considered are the most general peculiarities of uranium and thorium distributions in hydrothermal-metasomatic formations of three levels of substance formation: 1) in hydrothermal minerals; 2) in natural associations of these minerals (in the altered rocks, metasomatites, ores, etc.); 3) ordened series of zonally and in stage conjugated hydrothermal-metasomatic formations. Statistically stable recurrence of natural combinations of hydrothermal-metasomatic formations points out conjugation of their formation in the directed evolution in the general hydrothermal process. Series of metasomatic formations, the initial members of which are potassium metasomatites, mostly result in accumulation up to industrial concentrations of radioactive elements in final members of these formations. Development of midlow-temperature propylitic alterations in highly radiative rocks causes the same accumulation

ENDF/B Format

International Nuclear Information System (INIS)

Khalil, M.A.

1975-01-01

This document is a brief user's description of the format of ENDF/B, the evaluated neutron nuclear data library of the US National Nuclear Data Center. This summary is an aid to customers of the IAEA Nuclear Data Section when receiving data retrievals in ENDF/B format. For more detailed information the report BNL-50274 (ENDF-102) should be consulted. (author)

Geological factors of deposit formation

International Nuclear Information System (INIS)

Grushevoj, G.V.

1980-01-01

Geologic factors of hydrogenic uranium deposit formation are considered. Structural, formation and lithological-facies factors of deposit formation, connected with zones of stratal oxidation, are characterized. Peculiarities of deposit localization, connected with orogenic structures of Mesozoic and lenozoic age, are described. It is noted that deposits of anagenous group are widely spread in Paleozoic formations, infiltration uranium deposits are localized mainly in Cenozoic sediments, while uranium mineralization both anagenous and infiltration groups are widely developed in Mesozoic sediments. Anagenous deposits were formed in non-oxygen situation, their age varies from 200 to 55 mln years. Infiltration deposit formation is determined by asymmetric oxidation zonation, their age varies from 10 - 40 mln years to dozens of thousand years [ru

Designing for informed group formation

DEFF Research Database (Denmark)

Nicolajsen, Hanne Westh; Juel Jacobsen, Alice; Riis, Marianne

2012-01-01

A new design ―project preparation‖ preparing for the group formation in problem based project work is proposed and investigated. The main problem is to overcome group formation based on existing relations. The hypothesis is that theme development and group formation are somewhat counterproductive...

FORMATION CONSTANTS AND THERMODYNAMIC ...

African Journals Online (AJOL)

KEY WORDS: Metal complexes, Schiff base ligand, Formation constant, DFT calculation ... best values for the formation constants of the proposed equilibrium model by .... to its positive charge distribution and the ligand deformation geometry.

Stacked Star Formation Rate Profiles of Bursty Galaxies Exhibit “Coherent” Star Formation

Science.gov (United States)

Orr, Matthew E.; Hayward, Christopher C.; Nelson, Erica J.; Hopkins, Philip F.; Faucher-Giguère, Claude-André; Kereš, Dušan; Chan, T. K.; Schmitz, Denise M.; Miller, Tim B.

2017-11-01

In a recent work based on 3200 stacked Hα maps of galaxies at z˜ 1, Nelson et al. find evidence for “coherent star formation”: the stacked star formation rate (SFR) profiles of galaxies above (below) the “star formation main sequence” (MS) are above (below) that of galaxies on the MS at all radii. One might interpret this result as inconsistent with highly bursty star formation and evidence that galaxies evolve smoothly along the MS rather than crossing it many times. We analyze six simulated galaxies at z˜ 1 from the Feedback in Realistic Environments (FIRE) project in a manner analogous to the observations to test whether the above interpretations are correct. The trends in stacked SFR profiles are qualitatively consistent with those observed. However, SFR profiles of individual galaxies are much more complex than the stacked profiles: the former can be flat or even peak at large radii because of the highly clustered nature of star formation in the simulations. Moreover, the SFR profiles of individual galaxies above (below) the MS are not systematically above (below) those of MS galaxies at all radii. We conclude that the time-averaged coherent star formation evident stacks of observed galaxies is consistent with highly bursty, clumpy star formation of individual galaxies and is not evidence that galaxies evolve smoothly along the MS.

Manuel UNIMARC format bibliographique

CERN Document Server

2007-01-01

This manual is the French translation of the second edition of UNIMARC Manual: bibliographic format published in English in 1994 and completed by 5 updates published from 1996 to 2005. This 5th French edition is composite. It reproduces identically a part of the 4th edition published in 2002 and, for the fields of the format modified in the Update 5, it offers a new more structured presentation. This is a handbook dedicated to French-speaking users of the UNIMARC format for bibliographic descriptions.

Earth formation porosity log

International Nuclear Information System (INIS)

Smith, H.D.; Smith, M.P.; Schultz, W.E.

1977-01-01

A method for determining the porosity of earth formations in the vicinity of a cased well borehole is described, comprising the steps of: irradiating the earth formations in the vicinity of the cased well borehole with fast neutrons from a source of fast neutrons passed into the borehole; and generating a signal representative of the fast neutron population present in the well borehole at a location in the borehole, the signal is functionally related to the porosity of the earth formations in the vicinity of the borehole

Merging formation of FRC and its application to high-beta ST formation

International Nuclear Information System (INIS)

Ono, Y.; Inomoto, M.; Ueda, Y.; Matsuyama, T.; Ohshima, Y.; Katsurai, M.

2001-01-01

Merging formation of field-reversed configuration (FRC) explored not only a new scenario of highly-efficient FRC formation/amplification experiment but also a new boundary research between FRC, spheromak and spherical tokamak (ST). A new finding is that the produced FRC is transformed stably into an ultra-high-β ST by applying external toroidal field B t,ext . The toroidal field was observed to vanish around magnetic axis after the B t,ext application to the FRC, indicating formation of diamagnetic ST. The hollow current profile of FRC was maintained during the equilibrium transition, eliminating a need for the difficult hollow-current-formation process of start-up discharge of high-β ST. The energy-conversion effect of merging transformed the force-free merging spheromaks with paramagnetic current into the FRC with diamagnetic current and the further application of B t,ext did the FRC into the ultra-high-β (>60%)/diamagnetic ST, indicating the close relationship between FRC and ST in second stability. (author)

Restoring formation after leaching process

International Nuclear Information System (INIS)

Barrett, R.B.

1983-01-01

A method of restoring a formation which had uranium and other mineral values extracted by an alkaline lixiviant comprises introducing a source of phosphate in an amount sufficient to lower the level of soluble uranium compounds below that previously existing in the formation by the formation of insoluble uranium phosphate compounds

Formative Research in Educational Media.

Science.gov (United States)

Hodapp, Timothy

This paper distinguishes between basic research, applied research, and evaluation. Evaluation is broken down into two types: summative and formative. The limitations of formative research are presented, followed by a discussion of the value of the formative researcher participating in the product planning process. The types of data which formative…

Meningococcal biofilm formation

DEFF Research Database (Denmark)

Lappann, M.; Haagensen, Janus Anders Juul; Claus, H.

2006-01-01

We show that in a standardized in vitro flow system unencapsulated variants of genetically diverse lineages of Neisseria meningitidis formed biofilms, that could be maintained for more than 96 h. Biofilm cells were resistant to penicillin, but not to rifampin or ciprofloxacin. For some strains......, microcolony formation within biofilms was observed. Microcolony formation in strain MC58 depended on a functional copy of the pilE gene encoding the pilus subunit pilin, and was associated with twitching of cells. Nevertheless, unpiliated pilE mutants formed biofilms showing that attachment and accumulation......X alleles was identified among genetically diverse meningococcal strains. PilX alleles differed in their propensity to support autoaggregation of cells in suspension, but not in their ability to support microcolony formation within biofilms in the continuous flow system....

Tritiated ammonia formation

International Nuclear Information System (INIS)

Heung, L.K.

1995-01-01

When nitrogen was selected as the glovebox atmosphere for the Replacement Tritium Facility (RTF) at the Savannah River Site (SRS), a concern was raised as to the possibility of tritiated ammonia formation in the gloveboxes. Experimental data were produced to study the tritiated ammonia formation rate in a tritium and nitrogen mixture. A rate equation that closely simulates the experimental data was developed. This rate equation can be used to calculate the formation of tritiated ammonia from different concentrations of tritium and nitrogen. The reaction of T 2 and N 2 to form NT 3 is a slow process, particularly when the tritium concentration is low. The reaction requires weeks or months to reach radiochemical equilibrium dependent on the concentrations of the reactants. 4 refs., 6 figs., 1 tab

The NeXus data format

OpenAIRE

Könnecke, Mark; Akeroyd, Frederick A.; Osborn, Raymond; Peterson, Peter F.; Richter, Tobias; Suzuki, Jiro; Watts, Benjamin; Wintersberger, Eugen; Wuttke, Joachim; Bernstein, Herbert J.; Brewster, Aaron S.; Campbell, Stuart I.; Clausen, Björn; Cottrell, Stephen; Hoffmann, Jens Uwe

2015-01-01

NeXus is an effort by an international group of scientists to define a common data exchange and archival format for neutron, X-ray and muon experiments. NeXus is built on top of the scientific data format HDF5 and adds domain-specific rules for organizing data within HDF5 files, in addition to a dictionary of well defined domain-specific field names. The NeXus data format has two purposes. First, it defines a format that can serve as a container for all relevant data associated with a beamlin...

Inside-out Planet Formation. IV. Pebble Evolution and Planet Formation Timescales

Science.gov (United States)

Hu, Xiao; Tan, Jonathan C.; Zhu, Zhaohuan; Chatterjee, Sourav; Birnstiel, Tilman; Youdin, Andrew N.; Mohanty, Subhanjoy

2018-04-01

Systems with tightly packed inner planets (STIPs) are very common. Chatterjee & Tan proposed Inside-out Planet Formation (IOPF), an in situ formation theory, to explain these planets. IOPF involves sequential planet formation from pebble-rich rings that are fed from the outer disk and trapped at the pressure maximum associated with the dead zone inner boundary (DZIB). Planet masses are set by their ability to open a gap and cause the DZIB to retreat outwards. We present models for the disk density and temperature structures that are relevant to the conditions of IOPF. For a wide range of DZIB conditions, we evaluate the gap-opening masses of planets in these disks that are expected to lead to the truncation of pebble accretion onto the forming planet. We then consider the evolution of dust and pebbles in the disk, estimating that pebbles typically grow to sizes of a few centimeters during their radial drift from several tens of astronomical units to the inner, ≲1 au scale disk. A large fraction of the accretion flux of solids is expected to be in such pebbles. This allows us to estimate the timescales for individual planet formation and the entire planetary system formation in the IOPF scenario. We find that to produce realistic STIPs within reasonable timescales similar to disk lifetimes requires disk accretion rates of ∼10‑9 M ⊙ yr‑1 and relatively low viscosity conditions in the DZIB region, i.e., a Shakura–Sunyaev parameter of α ∼ 10‑4.

PCF File Format.

Energy Technology Data Exchange (ETDEWEB)

Thoreson, Gregory G [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-08-01

PCF files are binary files designed to contain gamma spectra and neutron count rates from radiation sensors. It is the native format for the GAmma Detector Response and Analysis Software (GADRAS) package [1]. It can contain multiple spectra and information about each spectrum such as energy calibration. This document outlines the format of the file that would allow one to write a computer program to parse and write such files.

Spatially-resolved star formation histories of CALIFA galaxies. Implications for galaxy formation

Science.gov (United States)

González Delgado, R. M.; Pérez, E.; Cid Fernandes, R.; García-Benito, R.; López Fernández, R.; Vale Asari, N.; Cortijo-Ferrero, C.; de Amorim, A. L.; Lacerda, E. A. D.; Sánchez, S. F.; Lehnert, M. D.; Walcher, C. J.

2017-11-01

This paper presents the spatially resolved star formation history (SFH) of nearby galaxies with the aim of furthering our understanding of the different processes involved in the formation and evolution of galaxies. To this end, we apply the fossil record method of stellar population synthesis to a rich and diverse data set of 436 galaxies observed with integral field spectroscopy in the CALIFA survey. The sample covers a wide range of Hubble types, with stellar masses ranging from M⋆ 109 to 7 × 1011 M⊙. Spectral synthesis techniques are applied to the datacubes to retrieve the spatially resolved time evolution of the star formation rate (SFR), its intensity (ΣSFR), and other descriptors of the 2D SFH in seven bins of galaxy morphology (E, S0, Sa, Sb, Sbc, Sc, and Sd) and five bins of stellar mass. Our main results are that (a) galaxies form very fast independently of their current stellar mass, with the peak of star formation at high redshift (z > 2). Subsequent star formation is driven by M⋆ and morphology, with less massive and later type spirals showing more prolonged periods of star formation. (b) At any epoch in the past, the SFR is proportional to M⋆, with most massive galaxies having the highest absolute (but lowest specific) SFRs. (c) While today, the ΣSFR is similar for all spirals and significantly lower in early-type galaxies (ETG), in the past, the ΣSFR scales well with morphology. The central regions of today's ETGs are where the ΣSFR reached the highest values (> 103 M⊙ Gyr-1 pc-2), similar to those measured in high-redshift star-forming galaxies. (d) The evolution of ΣSFR in Sbc systems matches that of models for Milky Way-like galaxies, suggesting that the formation of a thick disk may be a common phase in spirals at early epochs. (e) The SFR and ΣSFR in outer regions of E and S0 galaxies show that they have undergone an extended phase of growth in mass between z = 2 and 0.4. The mass assembled in this phase is in agreement with

Formation of multiple networks

DEFF Research Database (Denmark)

Magnani, Matteo; Rossi, Luca

2013-01-01

we introduce the first network formation model for multiple networks. Network formation models are among the most popular tools in traditional network studies, because of both their practical and theoretical impact. However, existing models are not sufficient to describe the generation of multiple...

Autonomous Formations of Multi-Agent Systems

Science.gov (United States)

Dhali, Sanjana; Joshi, Suresh M.

2013-01-01

Autonomous formation control of multi-agent dynamic systems has a number of applications that include ground-based and aerial robots and satellite formations. For air vehicles, formation flight ("flocking") has the potential to significantly increase airspace utilization as well as fuel efficiency. This presentation addresses two main problems in multi-agent formations: optimal role assignment to minimize the total cost (e.g., combined distance traveled by all agents); and maintaining formation geometry during flock motion. The Kuhn-Munkres ("Hungarian") algorithm is used for optimal assignment, and consensus-based leader-follower type control architecture is used to maintain formation shape despite the leader s independent movements. The methods are demonstrated by animated simulations.

GMC Collisions as Triggers of Star Formation. III. Density and Magnetically Regulated Star Formation

Energy Technology Data Exchange (ETDEWEB)

Wu, Benjamin [National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Tan, Jonathan C. [Department of Physics, University of Florida, Gainesville, FL 32611 (United States); Christie, Duncan [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Nakamura, Fumitaka [National Astronomical Observatory, Mitaka, Tokyo 181-8588 (Japan); Van Loo, Sven [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom); Collins, David, E-mail: ben.wu@nao.ac.jp [Department of Physics, Florida State University, Tallahassee, FL 32306-4350 (United States)

2017-06-01

We study giant molecular cloud (GMC) collisions and their ability to trigger star cluster formation. We further develop our three-dimensional magnetized, turbulent, colliding GMC simulations by implementing star formation subgrid models. Two such models are explored: (1) “Density-Regulated,” i.e., fixed efficiency per free-fall time above a set density threshold and (2) “Magnetically Regulated,” i.e., fixed efficiency per free-fall time in regions that are magnetically supercritical. Variations of parameters associated with these models are also explored. In the non-colliding simulations, the overall level of star formation is sensitive to model parameter choices that relate to effective density thresholds. In the GMC collision simulations, the final star formation rates and efficiencies are relatively independent of these parameters. Between the non-colliding and colliding cases, we compare the morphologies of the resulting star clusters, properties of star-forming gas, time evolution of the star formation rate (SFR), spatial clustering of the stars, and resulting kinematics of the stars in comparison to the natal gas. We find that typical collisions, by creating larger amounts of dense gas, trigger earlier and enhanced star formation, resulting in 10 times higher SFRs and efficiencies. The star clusters formed from GMC collisions show greater spatial substructure and more disturbed kinematics.

A format for phylogenetic placements.

Directory of Open Access Journals (Sweden)

Frederick A Matsen

Full Text Available We have developed a unified format for phylogenetic placements, that is, mappings of environmental sequence data (e.g., short reads into a phylogenetic tree. We are motivated to do so by the growing number of tools for computing and post-processing phylogenetic placements, and the lack of an established standard for storing them. The format is lightweight, versatile, extensible, and is based on the JSON format, which can be parsed by most modern programming languages. Our format is already implemented in several tools for computing and post-processing parsimony- and likelihood-based phylogenetic placements and has worked well in practice. We believe that establishing a standard format for analyzing read placements at this early stage will lead to a more efficient development of powerful and portable post-analysis tools for the growing applications of phylogenetic placement.

Uranium logging in earth formations

International Nuclear Information System (INIS)

Givens, W.W.

1979-01-01

A technique is provided for assaying the formations surrounding a borehole for uranium. A borehole logging tool cyclically irradiates the formations with neutrons and responds to neutron fluxes produced during the period of time that prompt neutrons are being produced by the neutron fission of uranium in the formations. A borehole calibration tool employs a steady-state (continuous output) neutron source, firstly, to produce a response to neutron fluxes in models having known concentrations of uranium and, secondly, to to produce a response to neutron fluxes in the formations surrounding the borehole. The neutron flux responses of the borehole calibration tool in both the model and the formations surrounding the borehole are utilized to correct the neutron flux response of the borehole logging tool for the effects of epithermal/thermal neutron moderation, scattering, and absorption within the borehole itself

Nanotopography induced contact guidance of the F11 cell line during neuronal differentiation: a neuronal model cell line for tissue scaffold development

International Nuclear Information System (INIS)

Wieringa, Paul; Micera, Silvestro; Tonazzini, Ilaria; Cecchini, Marco

2012-01-01

The F11 hybridoma, a dorsal root ganglion-derived cell line, was used to investigate the response of nociceptive sensory neurons to nanotopographical guidance cues. This established this cell line as a model of peripheral sensory neuron growth for tissue scaffold design. Cells were seeded on substrates of cyclic olefin copolymer (COC) films imprinted via nanoimprint lithography (NIL) with a grating pattern of nano-scale grooves and ridges. Different ridge widths were employed to alter the focal adhesion formation, thereby changing the cell/substrate interaction. Differentiation was stimulated with forskolin in culture medium consisting of either 1 or 10% fetal bovine serum (FBS). Per medium condition, similar neurite alignment was achieved over the four day period, with the 1% serum condition exhibiting longer, more aligned neurites. Immunostaining for focal adhesions found the 1% FBS condition to also have fewer, less developed focal adhesions. The robust response of the F11 to guidance cues further builds on the utility of this cell line as a sensory neuron model, representing a useful tool to explore the design of regenerative guidance tissue scaffolds. (paper)

Isolation and functional effects of monoclonal antibodies binding to thymidylate synthase.

Science.gov (United States)

Jastreboff, M M; Todd, M B; Malech, H L; Bertino, J R

1985-01-29

Monoclonal antibodies against electrophoretically pure thymidylate synthase from HeLa cells have been produced. Antibodies (M-TS-4 and M-TS-9) from hybridoma clones were shown by enzyme-linked immunoassay to recognize thymidylate synthase from a variety of human cell lines, but they did not bind to thymidylate synthase from mouse cell lines. The strongest binding of antibodies was observed to enzyme from HeLa cells. These two monoclonal antibodies bind simultaneously to different antigenic sites on thymidylate synthase purified from HeLa cells, as reflected by a high additivity index and results of cross-linked radioimmunoassay. Both monoclonal antibodies inhibit the activity of thymidylate synthase from human cell lines. The strongest inhibition was observed with thymidylate synthase from HeLa cells. Monoclonal antibody M-TS-9 (IgM subclass) decreased the rate of binding of [3H]FdUMP to thymidylate synthase in the presence of 5,10-methylenetetrahydrofolate while M-TS-4 (IgG1) did not change the rate of ternary complex formation. These data indicate that the antibodies recognize different epitopes on the enzyme molecule.

Production of a Human Antibody Library in the Phage-Display Vector pSEX81.

Science.gov (United States)

Welschof, M; Little, M; Dörsam, H

1998-01-01

Human monoclonal antibodies (MAbs) are more suitable than MAbs of animal origin for clinical applications because of lower hypersensitivity reactions, less formation of circulating immune complexes and lower anti-immunoglobulin responses The classical production of human MAbs via the hybridoma technique or Epstein-Barr virus (EBV) transformation is limited by the instability of cell lines, low antibody production, and the problems of imununizing humans with certain antigens (1,2). A promising alternative 1s the production of human recombinant antibodies (3). Recombinant DNA technology has made it possible to clone human antibody genes in vectors and to generate antibody expression libraries (4-7). One approach has been to amplify and recombine the IgG repertoire of an "immunized" donor. This has been used to isolate several antibodies related to diseases (8,9). In order to obtain more universal antibody libraries the naive IgM repertoire of several "unimmunized" donors were pooled (10,12). The complexity of the combinatorial libraries has been further increased by creating the so-called "semisynthetic" antibody libraries (22-14).

Free-format RPG IV

CERN Document Server

Martin, Jim

2013-01-01

This how-to guide offers a concise and thorough introduction to the increased productivity, better readability, and easier program maintenance that comes with the free-format style of programming in RPG IV. Although free-format information is available in IBM manuals, it is not separated from everything else, thereby requiring hours of tedious research to track down the information needed. This book provides everything one needs to know to write RPG IV in the free-format style, and author Jim Martin not only teaches rules and syntax but also explains how this new style of coding has the pot

Nuclear techniques in schistosomiasis: Towards a schistosome vaccine

International Nuclear Information System (INIS)

Taylor, D.W.

1986-01-01

The paper reviews recent advances in schistosome research achieved through the application of nuclear techniques and aimed at the development of a vaccine. Two principal areas are discussed: first, immune effector mechanisms; and secondly, the application of hybridoma and recombinant DNA technology to the problem of production of large quantities of parasite antigens suitable for inclusion in an experimental vaccine. (author)

Reflections about the mathematics teachers' formation

Directory of Open Access Journals (Sweden)

Maria José de Freitas Mendes

2010-06-01

Full Text Available This paper brings some reflections about the formation of the math teacher that made part of my marsters paper and that aimed to investigate the process of formation of the math teacher. The focus of this study incided at the contributions of teaching practice in the teacher's formation above the new paradigms of formation, as a professional development and as a reflexive teacher. These reflections, from the learning and teaching process and from the meaning of form a teacher analyse the crisis and the restructuration of the teacher's formation and conclude being necessary that in the graduation courses there's a character more practice to the pedagogical formation, making possible for the future teacher to develop attitudes of autonomy, reflexion and investigation

A possible formation scenario for dwarf spheroidal galaxies - III. Adding star formation histories to the fiducial model

Science.gov (United States)

Alarcón Jara, A. G.; Fellhauer, M.; Matus Carrillo, D. R.; Assmann, P.; Urrutia Zapata, F.; Hazeldine, J.; Aravena, C. A.

2018-02-01

Dwarf spheroidal galaxies are regarded as the basic building blocks in the formation of larger galaxies and are the most dark matter dominated systems in the Universe, known so far. There are several models that attempt to explain their formation and evolution, but they have problems modelling the formation of isolated dwarf spheroidal galaxies. Here, we will explain a possible formation scenario in which star clusters form inside the dark matter halo of a dwarf spheroidal galaxy. These star clusters suffer from low star formation efficiency and dissolve while orbiting inside the dark matter halo. Thereby, they build the faint luminous components that we observe in dwarf spheroidal galaxies. In this paper, we study this model by adding different star formation histories to the simulations and compare the results with our previous work and observational data to show that we can explain the formation of dwarf spheroidal galaxies.

Plant Formate Dehydrogenase

Energy Technology Data Exchange (ETDEWEB)

John Markwell

2005-01-10

The research in this study identified formate dehydrogenase, an enzyme that plays a metabolic role on the periphery of one-carbon metabolism, has an unusual localization in Arabidopsis thaliana and that the enzyme has an unusual kinetic plasticity. These properties make it possible that this enzyme could be engineered to attempt to engineer plants with an improved photosynthetic efficiency. We have produced transgenic Arabidopsis and tobacco plants with increased expression of the formate dehydrogenase enzyme to initiate further studies.

Formation à distance et activité du stagiaire de la formation professionnelle continue

OpenAIRE

Verquin-Savarieau, Béatrice

2014-01-01

Quels contenus des lettres de missions pour quelles démarches et activités d’ingénierie de formation, pour des étudiants salariés en activité et suivant leurs études à distance ? Cet article questionne le stage de formation professionnelle continue dans le cadre d’une formation hybride. Il s’agit d’interroger en particulier la conception de la mission de stage, en tant que contenu opératoire facilitant les transformations des sujets dans l’action. Nous présenterons le rôle crucial joué par la...

XML-based DICOM data format.

Science.gov (United States)

Yu, Cong; Yao, Zhihong

2010-04-01

To enhance the readability, improve the structure, and facilitate the sharing of digital imaging and communications in medicine (DICOM) files, this research proposed one kind of XML-based DICOM data format. Because XML Schema offers great flexibility for expressing constraints on the content model of elements, we used it to describe the new format, thus making it consistent with the one originally defined by DICOM. Meanwhile, such schemas can be used in the creation and validation of the XML-encoded DICOM files, acting as a standard for data transmission and sharing on the Web. Upon defining the new data format, we started with representing a single data element and further improved the whole data structure with the method of modularization. In contrast to the original format, the new one possesses better structure without loss of related information. In addition, we demonstrated the application of XSLT and XQuery. All of the advantages mentioned above resulted from this new data format.

Mesoarchean Banded Iron Formation sequences in Dixon Island-Cleaverville Formation, Pilbara Australia: Oxygenic signal from DXCL project

Science.gov (United States)

Kiyokawa, S.; Ito, T.; Ikehara, M.; Yamaguchi, K. E.; Naraoka, H.; Onoue, T.; Horie, K.; Sakamoto, R.; Aihara, Y.; Miki, T.

2013-12-01

The 3.2-3.1 Ga Dixon island-Cleaverville formations are well-preserved Banded Iron Formation (BIF) within hydrothermal oceanic sequence at oceanic island arc setting (Kiyokawa et al., 2002, 2006, 2012). The stratigraphy of the Dixon Island (3195+15Ma) -Cleaverville (3108+13Ma) formations shows the well preserved environmental condition at the Mesoarchean ocean floor. The stratigraphy of these formations are formed about volcano-sedimentary sequences with hydrothermal chert, black shale and banded iron formation to the top. Based on the scientific drilling of DXCL project at 2007 and 2011, detail lithology between BIF sequence was clearly understood. Four drilling holes had been done at coastal sites; the Dixon Island Formation is DX site (100m) and the Cleaverville Formation is CL2 (40m), CL1 (60m) and CL3 (200m) sites and from stratigraphic bottom to top. Coarsening and thickening upward black shale-BIF sequences are well preserved of the stratigraphy form the core samples. The Dixon Island Formation consists komatiite-rhyolite sequences with many hydrothermal veins and very fine laminated cherty rocks above them. The Cleaverville Formation contains black shale, fragments-bearing pyroclastic beds, white chert, greenish shale and BIF. The CL3 core, which drilled through BIF, shows siderite-chert beds above black shale identified before magnetite lamination bed. U-Pb SHRIMP data of the tuff in lower Dixon Island Formation is 3195+15 Ma and the pyroclastic sequence below the Cleaverville BIF is 3108+13 Ma. Sedimentation rate of these sequence is 2-8 cm/ 1000year. The hole section of the organic carbon rich black shales below BIF are similar amount of organic content and 13C isotope (around -30per mill). There are very weak sulfur MIF signal (less 0.2%) in these black shale sequence. Our result show that thick organic rich sediments may be triggered to form iron rich siderite and magnetite iron beds. The stratigraphy in this sequence quite resemble to other Iron

Observsational Planet Formation

Science.gov (United States)

Dong, Ruobing; Zhu, Zhaohuan; Fung, Jeffrey

2017-06-01

Planets form in gaseous protoplanetary disks surrounding newborn stars. As such, the most direct way to learn how they form from observations, is to directly watch them forming in disks. In the past, this was very difficult due to a lack of observational capabilities; as such, planet formation was largely a subject of pure theoretical astrophysics. Now, thanks to a fleet of new instruments with unprecedented resolving power that have come online recently, we have just started to unveil features in resolve images of protoplanetary disks, such as gaps and spiral arms, that are most likely associated with embedded (unseen) planets. By comparing observations with theoretical models of planet-disk interactions, the masses and orbits of these still forming planets may be constrained. Such planets may help us to directly test various planet formation models. This marks the onset of a new field — observational planet formation. I will introduce the current status of this field.

Les métiers innovants de la formation. Le champ de la formation professionnelle et l'ingénierie de formation à distance

OpenAIRE

Marty, Olivier

2013-01-01

National audience; This document is extracted from a conference for PhD students at La Sorbonne University (Paris) about innovative teaching professions. It describes and analyses the crafts of vocational education as well as public distance education engineering.; Ce document est le support d'une conférence sur les métiers innovants de la formation. Après les définitions d'usage, il décrit et analyse les métiers de la formation professionnelle continue et l'ingénierie de formation à distance...

Types of tectonic structures, sedimentary volcanogenetic formations of a mantle, favourable processes for exogenetic and polygenetic uranium deposits formation

International Nuclear Information System (INIS)

Danchev, V.I.; Komarnitskij, G.M.; Levin, V.N.; Shumlyanskij, V.A.

1985-01-01

Factors, affecting mineralization processes are considered. Characteristic features of uranium-bearing provinces are as follows: the presence of crust of continental type; deep-seated tectonic structures-rises and saggings, roofs, gneiss domes, rift zones and transform fractures; specialization for uranium of sedimentary and magmatic formations; the presence of manifestation regions of deep thermal and gaseous flow, etc. In uranium-bearing provinces territories favourable for the manifestation of different types of uranium mineralization: metamorphogenetic, polygenetic and exogenetic ones, are singled out. Different epochs of uranium ore formation are established. In sedimentary masses tectonic regime and climate are of special importance, and for epigenetic deposits, formed with an aid of underground waters-hydrogeological conditions. In the limits of the main structural elements of the Earth crust and geotectonic structures of higher orders the following types of sedimentary and volcanic formations can be singled out: 1-formations with exogenous uranium mineralization; 2-formations, accumulated in the epochs of epigenous ore formation; 3-formations fav ourable for epigenous uranium deposit formation; 4-formations unfavourable for the formation and localization of uranium mineralization

Mycoplasma infection of cell lines can simulate the expression of Fc receptors by binding of the carbohydrate moiety of antibodies.

Science.gov (United States)

Lemke, H; Krausse, R; Lorenzen, J; Havsteen, B

1985-05-01

During the production of Fc receptor (FcR)-bearing hybridomas it was observed with a particular monoclonal anti-sheep red blood cell antibody (anti-SRBC 1/5, IgG1) that the contamination with Mycoplasma arginini of in vitro cultured cell lines leads to an apparent FcR activity. This property did not correspond with the serological typing since other antibodies of the same isotype could not support FcR rosette formation. Another mycoplasma strain M. orale lacked this property. Analysis of the binding reaction revealed that M. arginini contains a lectin which binds the carbohydrate moiety of the anti-SRBC 1/5 antibody, i.e. anti-SRBC 1/5 synthesized under the influence of tunicamycin or deglycosylated by NaIO4 oxidation did not support rosette formation. These data suggest that binding of antibodies to certain mycoplasma strains may be a pathogenic factor during mycoplasma infections by masking the microorganisms with the host's own defense molecules. The experiments with M. arginini-infected cell lines gain immunological importance since we obtained identical results with staphylococcal protein A, as another bacteriological FcR, and cell lines expressing intrinsic membrane FcR. Although it is an open question whether the glycoconjugates are directly bound by the FcR or else by influencing the three-dimensional structure of the antibodies, it seems possible that FcR in general may be lectins.

Field-Portable Immunoassay Instruments and Reagents to Measure Chelators and Mobile Forms of Uranium

International Nuclear Information System (INIS)

Blake, Diane A.

2006-01-01

Progress Report Date: 01/23/06 (report delayed due to Hurricane Katrina) Report of results to date: The goals of this 3-year project are to: (1) update and successfully deploy our present immunosensors at DOE sites; (2) devise immunosensor-based assays for Pb(II), Hg(II), chelators, and/or Cr(III) in surface and groundwater; and (3) develop new technologies in antibody engineering that will enhance this immunosensor program. Note: Work on this project was temporarily disrupted when Hurricane Katrina shut down the University on August 29, 2005. While most of the reagents stored in our refrigerators and freezers were destroyed, all of our hybridoma cell lines were saved because they had been stored in liquid nitrogen. We set up new tissue culture reactors with the hybridomas that synthesize the anti-uranium antibodies, and are purifying new monoclonal antibodies from these culture supernatants. Both the in-line and the field-portable sensor were rescued from our labs in New Orleans in early October, and we continued experiments with these sensors in the temporary laboratory we set up in Hammond, LA at Southeastern Louisiana University

Generation of a monoclonal antibody against the glycosylphosphatidylinositol-linked protein Rae-1 using genetically engineered tumor cells.

Science.gov (United States)

Hu, Jiemiao; Vien, Long T; Xia, Xueqing; Bover, Laura; Li, Shulin

2014-02-04

Although genetically engineered cells have been used to generate monoclonal antibodies (mAbs) against numerous proteins, no study has used them to generate mAbs against glycosylphosphatidylinositol (GPI)-anchored proteins. The GPI-linked protein Rae-1, an NKG2D ligand member, is responsible for interacting with immune surveillance cells. However, very few high-quality mAbs against Rae-1 are available for use in multiple analyses, including Western blotting, immunohistochemistry, and flow cytometry. The lack of high-quality mAbs limits the in-depth analysis of Rae-1 fate, such as shedding and internalization, in murine models. Moreover, currently available screening approaches for identifying high-quality mAbs are excessively time-consuming and costly. We used Rae-1-overexpressing CT26 tumor cells to generate 60 hybridomas that secreted mAbs against Rae-1. We also developed a streamlined screening strategy for selecting the best anti-Rae-1 mAb for use in flow cytometry assay, enzyme-linked immunosorbent assay, Western blotting, and immunostaining. Our cell line-based immunization approach can yield mAbs against GPI-anchored proteins, and our streamlined screening strategy can be used to select the ideal hybridoma for producing such mAbs.

Effect of operating conditions in production of diagnostic Salmonella Enteritidis O-antigen-specific monoclonal antibody in different bioreactor systems.

Science.gov (United States)

Ayyildiz-Tamis, Duygu; Nalbantsoy, Ayse; Elibol, Murat; Deliloglu-Gurhan, Saime Ismet

2014-01-01

In this study, different cultivation systems such as roller bottles (RB), 5-L stirred-tank bioreactor (STR), and disposable bioreactors were used to cultivate hybridoma for lab-scale production of Salmonella Enteritidis O-antigen-specific monoclonal antibody (MAb). Hybridoma cell line was cultivated in either serum-containing or serum-free medium (SFM) culture conditions. In STR, MAb production scaled up to 4 L, and production capabilities of the cells were also evaluated in different featured production systems. Moreover, the growth parameters of the cells in all production systems such as glucose consumption, lactate and ammonia production, and also MAb productivities were determined. Collected supernatants from the reactors were concentrated by a cross-flow filtration system. In conclusion, cells were not adapted to SFM in RB and STR. Therefore, less MAb titer in both STR and RB systems with SFM was observed compared to the cultures containing fetal bovine serum-supplemented medium. A higher MAb titer was gained in the membrane-aerated system compared to those in STR and RB. Although the highest MAb titer was obtained in the static membrane bioreactor system, the highest productivity was obtained in STR operated in semicontinuous mode with overlay aeration.

Single Chain Variable Fragments Produced in Escherichia coli against Heat-Labile and Heat-Stable Toxins from Enterotoxigenic E. coli.

Directory of Open Access Journals (Sweden)

Christiane Y Ozaki

Full Text Available Diarrhea is a prevalent pathological condition frequently associated to the colonization of the small intestine by enterotoxigenic Escherichia coli (ETEC strains, known to be endemic in developing countries. These strains can produce two enterotoxins associated with the manifestation of clinical symptoms that can be used to detect these pathogens. Although several detection tests have been developed, minimally equipped laboratories are still in need of simple and cost-effective methods. With the aim to contribute to the development of such diagnostic approaches, we describe here two mouse hybridoma-derived single chain fragment variable (scFv that were produced in E. coli against enterotoxins of ETEC strains.Recombinant scFv were developed against ETEC heat-labile toxin (LT and heat-stable toxin (ST, from previously isolated hybridoma clones. This work reports their design, construction, molecular and functional characterization against LT and ST toxins. Both antibody fragments were able to recognize the cell-interacting toxins by immunofluorescence, the purified toxins by ELISA and also LT-, ST- and LT/ST-producing ETEC strains.The developed recombinant scFvs against LT and ST constitute promising starting point for simple and cost-effective ETEC diagnosis.

An Adaptable Seismic Data Format

Science.gov (United States)

Krischer, Lion; Smith, James; Lei, Wenjie; Lefebvre, Matthieu; Ruan, Youyi; de Andrade, Elliott Sales; Podhorszki, Norbert; Bozdağ, Ebru; Tromp, Jeroen

2016-11-01

We present ASDF, the Adaptable Seismic Data Format, a modern and practical data format for all branches of seismology and beyond. The growing volume of freely available data coupled with ever expanding computational power opens avenues to tackle larger and more complex problems. Current bottlenecks include inefficient resource usage and insufficient data organization. Properly scaling a problem requires the resolution of both these challenges, and existing data formats are no longer up to the task. ASDF stores any number of synthetic, processed or unaltered waveforms in a single file. A key improvement compared to existing formats is the inclusion of comprehensive meta information, such as event or station information, in the same file. Additionally, it is also usable for any non-waveform data, for example, cross-correlations, adjoint sources or receiver functions. Last but not least, full provenance information can be stored alongside each item of data, thereby enhancing reproducibility and accountability. Any data set in our proposed format is self-describing and can be readily exchanged with others, facilitating collaboration. The utilization of the HDF5 container format grants efficient and parallel I/O operations, integrated compression algorithms and check sums to guard against data corruption. To not reinvent the wheel and to build upon past developments, we use existing standards like QuakeML, StationXML, W3C PROV and HDF5 wherever feasible. Usability and tool support are crucial for any new format to gain acceptance. We developed mature C/Fortran and Python based APIs coupling ASDF to the widely used SPECFEM3D_GLOBE and ObsPy toolkits.

Planetesimals and Planet Formation

Science.gov (United States)

Chambers, John

The first step in the standard model for planet formation is the growth of gravitationally bound bodies called ``planetesimals'' from dust grains in a protoplanetary disk. Currently, we do not know how planetesimals form, how long they take to form, or what their sizes and mechanical properties are. The goal of this proposal is to assess how these uncertainties affect subsequent stages of planetary growth and the kind of planetary systems that form. The work will address three particular questions: (i) Can the properties of small body populations in the modern Solar System constrain the properties of planetesimals? (ii) How do the properties of planetesimals affect the formation of giant planets? (iii) How does the presence of a water ice condensation front (the ``snow line'') in a disk affect planetesimal formation and the later stages of planetary growth? These questions will be examined with computer simulations of planet formation using new computer codes to be developed as part of the proposal. The first question will be addressed using a statistical model for planetesimal coagulation and fragmentation. This code will be merged with the proposer's Mercury N-body integrator code to model the dynamics of large protoplanets in order to address the second question. Finally, a self- consistent model of disk evolution and the radial transport of water ice and vapour will be added to examine the third question. A theoretical understanding of how planets form is one of the key goals of NASA and the Origins of Solar Systems programme. Researchers have carried out many studies designed to address this goal, but the questions of how planetesimals form and how their properties affect planet formation have received relatively little attention. The proposed work will help address these unsolved questions, and place other research in context by assessing the importance of planetesimal origins and properties for planet formation.

Formation of double layers

International Nuclear Information System (INIS)

Leung, P.; Wong, A.Y.; Quon, B.H.

1981-01-01

Experiments on both stationary and propagating double layers and a related analytical model are described. Stationary double layers were produced in a multiple plasma device, in which an electron drift current was present. An investigation of the plasma parameters for the stable double layer condition is described. The particle distribution in the stable double layer establishes a potential profile, which creates electron and ion beams that excite plasma instabilities. The measured characteristics of the instabilities are consistent with the existence of the double layer. Propagating double layers are formed when the initial electron drift current is large. Ths slopes of the transition region increase as they propagate. A physical model for the formation of a double layer in the experimental device is described. This model explains the formation of the low potential region on the basis of the space charge. This space charge is created by the electron drift current. The model also accounts for the role of ions in double layer formation and explains the formation of moving double layers. (Auth.)

Medusae Fossae Formation

Science.gov (United States)

2002-01-01

(Released 10 April 2002) The Science This THEMIS visible image was acquired near 7o S, 172o W (188o E) and shows a remarkable martian geologic deposit known as the Medusae Fossae Formation. This Formation, seen here as the raised plateau in the upper two-thirds of the image, is a soft, easily eroded deposit that extends for nearly 1,000 km along the equator of Mars. In this region the deposit has been heavily eroded by the wind to produce a series of linear ridges called yardangs. These parallel ridges point in direction of the prevailing winds that carved them, and demonstrate the power of martian winds to sculpt the dry landscape of Mars. The Medusae Fossae Formation has been completely stripped from the surface in the lower third of the image, revealing a harder layer below that is more resistant to wind erosion. The easily eroded nature of the Medusae Fossae Formation suggests that it is composed of weakly cemented particles, and was most likely formed by the deposition of wind-blown dust or volcanic ash. Several ancient craters that were once completely buried by this deposit are being exposed, or exhumed, as the overlying Medusae Formation is removed. Very few impact craters are visible on this Formation, indicating that the surface seen today is relatively young, and that the processes of erosion are likely to be actively occurring. The Story Medusa of Greek mythology fame, the name-giver to this region, had snaky locks of hair that could turn a person to stone. Wild and unruly, this monster of the underworld could certainly wreak havoc on the world of the human imagination. As scary as she was, Medusa would have no advantage over the fierce, masterful winds blowing across Mars, which once carved the streaky, terrain at the top of this image. Wild and whipping, these winds have slowly eroded away the 'topsoil,' revealing ancient craters and other surface features they once covered. The loosely cemented particles of this 'topsoil' are likely made up of dust

Designing for informed group formation

DEFF Research Database (Denmark)

Nicolajsen, Hanne Westh; Juel Jacobsen, Alice; Riis, Marianne

2012-01-01

A new design ―project preparation‖ preparing for the group formation in problem based project work is proposed and investigated. The main problem is to overcome group formation based on existing relations. The hypothesis is that theme development and group formation are somewhat counterproductive....... Following research based design methodology an experiment separating the two was initiated.This was to provide for more openness and creativity in contrast to a design in which existing relations seem predominant....

Laser filament-induced aerosol formation

Directory of Open Access Journals (Sweden)

H. Saathoff

2013-05-01

Full Text Available Using the aerosol and cloud simulation chamber AIDA, we investigated the laser filament induced particle formation in ambient air, humid synthetic air, humid nitrogen, argon–oxygen mixture, and pure argon in order to simulate the particle formation under realistic atmospheric conditions as well as to investigate the influence of typical gas-phase atmospheric constituents on the particle formation. Terawatt laser plasma filaments generated new particles in the size range 3 to 130 nm with particle production rates ranging from 1 × 107 to 5 × 109 cm−3 plasma s−1 for the given experimental conditions. In all cases the particle formation rates increased exponentially with the water content of the gas mixture. Furthermore, the presence of a few ppb of trace gases like SO2 and α-pinene clearly enhanced the particle yield by number, the latter also by mass. Our findings suggest that new particle formation is efficiently supported by oxidized species like acids generated by the photoionization of both major and minor components of the air, including N2, NH3, SO2 and organics.

Automation of Tabular Application Formation

Directory of Open Access Journals (Sweden)

S. V. Zykin

2013-01-01

Full Text Available The paper considers automation problems of the interface formation between a table and a relational database. The task description is formalized and the description of the existing approaches to formation of data representations on an example of widely widespread CASE-tools is submitted. The definition of intermediate data representation as a ”join table” is offered, which is used for maintenance of correctness of data representation formation, and also is necessary for direct and inverse data transformations. On the basis of lossless join property and realized dependencies, the concept and a way of context formation of the application and restrictions is introduced. The considered material is further used for constructing an inverse data transformation from tabular presentation into a relational one. On the basis of relationships properties on a database scheme, the partial order on the relations is established, and the restriction of acyclic databases schemes is introduced. The received results are further used at the analysis of principles of formation of inverse data transformation, and the basic details of such a transformation algorithm are considered.

Decentralized Control for Scalable Quadcopter Formations

Directory of Open Access Journals (Sweden)

Qasim Ali

2016-01-01

Full Text Available An innovative framework has been developed for teamwork of two quadcopter formations, each having its specified formation geometry, assigned task, and matching control scheme. Position control for quadcopters in one of the formations has been implemented through a Linear Quadratic Regulator Proportional Integral (LQR PI control scheme based on explicit model following scheme. Quadcopters in the other formation are controlled through LQR PI servomechanism control scheme. These two control schemes are compared in terms of their performance and control effort. Both formations are commanded by respective ground stations through virtual leaders. Quadcopters in formations are able to track desired trajectories as well as hovering at desired points for selected time duration. In case of communication loss between ground station and any of the quadcopters, the neighboring quadcopter provides the command data, received from the ground station, to the affected unit. Proposed control schemes have been validated through extensive simulations using MATLAB®/Simulink® that provided favorable results.

Frequency formats, probability formats, or problem structure? A test of the nested-sets hypothesis in an extensional reasoning task

Directory of Open Access Journals (Sweden)

William P. Neace

2008-02-01

Full Text Available Five experiments addressed a controversy in the probability judgment literature that centers on the efficacy of framing probabilities as frequencies. The natural frequency view predicts that frequency formats attenuate errors, while the nested-sets view predicts that highlighting the set-subset structure of the problem reduces error, regardless of problem format. This study tested these predictions using a conjunction task. Previous studies reporting that frequency formats reduced conjunction errors confounded reference class with problem format. After controlling this confound, the present study's findings show that conjunction errors can be reduced using either a probability or a frequency format, that frequency effects depend upon the presence of a reference class, and that frequency formats do not promote better statistical reasoning than probability formats.

The NeXus data format.

Science.gov (United States)

Könnecke, Mark; Akeroyd, Frederick A; Bernstein, Herbert J; Brewster, Aaron S; Campbell, Stuart I; Clausen, Björn; Cottrell, Stephen; Hoffmann, Jens Uwe; Jemian, Pete R; Männicke, David; Osborn, Raymond; Peterson, Peter F; Richter, Tobias; Suzuki, Jiro; Watts, Benjamin; Wintersberger, Eugen; Wuttke, Joachim

2015-02-01

NeXus is an effort by an international group of scientists to define a common data exchange and archival format for neutron, X-ray and muon experiments. NeXus is built on top of the scientific data format HDF5 and adds domain-specific rules for organizing data within HDF5 files, in addition to a dictionary of well defined domain-specific field names. The NeXus data format has two purposes. First, it defines a format that can serve as a container for all relevant data associated with a beamline. This is a very important use case. Second, it defines standards in the form of application definitions for the exchange of data between applications. NeXus provides structures for raw experimental data as well as for processed data.

Forces in strategy formation

DEFF Research Database (Denmark)

Steensen, Elmer Fly; Sanchez, Ron

2008-01-01

This chapter proposes that organizational strategy formation should be characterized theoretically as a process that is subject to several interacting forces, rather than represented by separate discrete decisionmodels or theoretic perspectives, as is commonly done in the strategic management...... literature. Based on an extensive review of relevant theory and empirical work in strategic decision-making, organizational change theory, cognitive and social psychology, and strategy processes, seven kinds of ''forces'' - rational, imposed, teleological, learning, political, heuristic, and social...... - are identified as interacting in and having significant influence on the strategy formation process. It is further argued that by applying a holistic ''forces-view'' of the significant and interacting influences on strategy formation, we can better understand the dynamics and challenges in managing the process...

New Particle Formation Study Final Campaign Report

Energy Technology Data Exchange (ETDEWEB)

Smith, JN; McMurry, PH [University of Minnesota

2015-01-01

The scientific foci of the New Particle Formation Study were the formation and evolution of atmospheric aerosols and the impacts of newly formed particles on cloud processes. Specifically, we planned to: (1) to identify the species and mechanisms responsible for the initial steps of new particle formation, i.e., the formation of thermodynamically stable clusters; (2) investigate the role of acid-base chemistry in new particle growth through measurements of ammonia and amines as well as organic and inorganic acids in both atmospheric nanoparticles and the gas phase; (3) investigate the contribution of other surface area or volume-controlled processes to nanoparticle formation and growth; (4) create a comprehensive dataset related to new particle formation and growth that can be used as input for our own thermodynamic models as well as the modeling efforts by our Department of Energy (DOE) Aerosol Life Cycle working group collaborators; (5) characterize the increase of the number and activity of cloud condensation nuclei (CCN) due to particle formation and growth; (6) determine the regional extent of new particle formation to address the role that atmospheric transport plays in determining the impacts, if any, of new particle formation on cloud number and properties.

Star Formation in Irregular Galaxies.

Science.gov (United States)

Hunter, Deidre; Wolff, Sidney

1985-01-01

Examines mechanisms of how stars are formed in irregular galaxies. Formation in giant irregular galaxies, formation in dwarf irregular galaxies, and comparisons with larger star-forming regions found in spiral galaxies are considered separately. (JN)

The relationship between sucrose hydrolysis, sorbitol formation and mineral ion concentration during bioethanol formation using Zymomonas mobilis 2716

Energy Technology Data Exchange (ETDEWEB)

Doelle, M.B.; Doelle, H.W. (Queensland Univ., St. Lucia (Australia). Dept. of Microbiology); Greenfield, P.F. (Queensland Univ., St. Lucia (Australia). Dept. of Chemical Engineering)

1990-11-01

Investigations into the relationship between sucrose hydrolysis, sorbitol formation and mineral ion concentration during bioethanol formation by Zymomonas mobilis 2716 revealed two distinct phenomena responsible for carbon flow diversion, a 'sucrose effect' and a 'salt effect'. Neither of the two phenomena affects sucrose hydrolysis, but they divert carbon flow of the fructose monomer leading to its own accumulation, sorbitol or oligosaccharide formation. Sucrose concentrations in excess of 15% (w/v) led to sorbitol formation, the level of which may exceed 2% (w/v) depending upon glucose accumulation during sucrose hydrolysis. Increasing mineral ion concentrations led initially to carbon losses and finally to fructose accumulation instead of sorbitol formation. This carbon loss can be corrected by the addition of invertase, which in turn leads to an increase in sorbitol, fructose and ethanol. Potassium and chloride are the dominant ions responsible for suppression of sorbitol formation and fructose uptake, encouraging oligosaccharide formation. These fructooligosaccharides must be of a type which can be converted to fructose, sorbitol and ethanol through the action of invertase. The requirement of invertase addition to prevent fructooligosaccharide formation is indirect evidence that Z. mobilis 2716 does not produce invertase. (orig.).

Antigen presentation by resting B cells. Radiosensitivity of the antigen-presentation function and two distinct pathways of T cell activation

International Nuclear Information System (INIS)

Ashwell, J.D.; DeFranco, A.L.; Paul, W.E.; Schwartz, R.H.

1984-01-01

In this report we have examined the ability of small resting B cells to act as antigen-presenting cells (APC) to antigen-specific MHC-restricted T cells as assessed by either T cell proliferation or T cell-dependent B cell stimulation. We found that 10 of 14 in vitro antigen-specific MHC-restricted T cell clones and lines and three of four T cell hybridomas could be induced to either proliferate or secrete IL-2 in the presence of lightly irradiated (1,000 rads) purified B cells and the appropriate foreign antigen. All T cell lines and hybridomas were stimulated to proliferate or make IL-2 by macrophage- and dendritic cell-enriched populations and all T cells tested except one hybridoma caused B cell activation when stimulated with B cells as APC. Furthermore, lightly irradiated, highly purified syngeneic B cells were as potent a source of APC for inducing B cell activation as were low density dendritic and macrophage-enriched cells. Lymph node T cells freshly taken from antigen-primed animals were also found to proliferate when cultured with purified B cells and the appropriate antigen. This APC function was easily measured when the cells were irradiated with 1,000 rads, but was greatly diminished or absent when they were irradiated with 3,300 rads. In addition, this radiosensitivity allowed us to easily distinguish B cell antigen presentation from presentation by the dendritic cell and macrophage, as the latter was resistant to 3,300 rads. Finally, one T cell clone that failed to proliferate when B cells were used as APC was able to recruit allogeneic B cells to proliferate in the presence of syngeneic B cells and the appropriate antigen. This result suggests that there are at least two distinct pathways of activation in T cells, one that leads to T cell proliferation and one that leads to the secretion of B cell recruitment factor(s)

ENDF/B-5 formats manual 1984

Energy Technology Data Exchange (ETDEWEB)

Kinsey, R; Magurno, B A

1986-09-01

The ENDF-5 Format, originally the format of the US Evaluated Nuclear Data File ENDF/B-5, was internationally recommended for the computer storage, processing and exchange of evaluated neutron nuclear data. The present document contains the original Formats Manual of 1979, updated with revisions of Nov. 1983. (author) Figs, tabs

Stratigraphy and dissolution of the Rustler Formation

International Nuclear Information System (INIS)

Bachman, G.O.

1987-01-01

This report describes the physical stratigraphy of the Rustler Formation, because the Waste Isolation Pilot Plant will be constructed in salt beds that underlie this formation. Described are subdivisions of the formations, the major karst features, and a proposed method for the formation of Nash Draw. 2 refs., 2 figs

Star Formation in low mass galaxies

Science.gov (United States)

Mehta, Vihang

2018-01-01

Our current hierarchical view of the universe asserts that the large galaxies we see today grew via mergers of numerous smaller galaxies. As evidenced by recent literature, the collective impact of these low mass galaxies on the universe is more substantial than previously thought. Studying the growth and evolution of these low mass galaxies is critical to our understanding of the universe as a whole. Star formation is one of the most important ongoing processes in galaxies. Forming stars is fundamental to the growth of a galaxy. One of the main goals of my thesis is to analyze the star formation in these low mass galaxies at different redshifts.Using the Hubble UltraViolet Ultra Deep Field (UVUDF), I investigate the star formation in galaxies at the peak of the cosmic star formation history using the ultraviolet (UV) light as a star formation indicator. Particularly, I measure the UV luminosity function (LF) to probe the volume-averaged star formation properties of galaxies at these redshifts. The depth of the UVUDF is ideal for a direct measurement of the faint end slope of the UV LF. This redshift range also provides a unique opportunity to directly compare UV to the "gold standard" of star formation indicators, namely the Hα nebular emission line. A joint analysis of the UV and Hα LFs suggests that, on average, the star formation histories in low mass galaxies (~109 M⊙) are more bursty compared to their higher mass counterparts at these redshifts.Complementary to the analysis of the average star formation properties of the bulk galaxy population, I investigate the details of star formation in some very bursty galaxies at lower redshifts selected from Spitzer Large Area Survey with Hyper-Suprime Cam (SPLASH). Using a broadband color-excess selection technique, I identify a sample of low redshift galaxies with bright nebular emission lines in the Subaru-XMM Deep Field (SXDF) from the SPLASH-SXDF catalog. These galaxies are highly star forming and have

Standard exercise report format (SERF)

International Nuclear Information System (INIS)

Anon.

1995-01-01

This talk summarizes the reasons for the development of draft SERF the Standard Exercise Report Format used for reporting the results of emergency preparedness exercises, and gives a summary of the format and rational behind it

Heating systems for heating subsurface formations

Science.gov (United States)

Nguyen, Scott Vinh [Houston, TX; Vinegar, Harold J [Bellaire, TX

2011-04-26

Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

Formation of topological defects

International Nuclear Information System (INIS)

Vachaspati, T.

1991-01-01

We consider the formation of point and line topological defects (monopoles and strings) from a general point of view by allowing the probability of formation of a defect to vary. To investigate the statistical properties of the defects at formation we give qualitative arguments that are independent of any particular model in which such defects occur. These arguments are substantiated by numerical results in the case of strings and for monopoles in two dimensions. We find that the network of strings at formation undergoes a transition at a certain critical density below which there are no infinite strings and the closed-string (loop) distribution is exponentially suppressed at large lengths. The results are contrasted with the results of statistical arguments applied to a box of strings in dynamical equilibrium. We argue that if point defects were to form with smaller probability, the distance between monopoles and antimonopoles would decrease while the monopole-to-monopole distance would increase. We find that monopoles are always paired with antimonopoles but the pairing becomes clean only when the number density of defects is small. A similar reasoning would also apply to other defects

Method for detecting and locating sand-producing zones in friable, unconsolidated sandstone formations of subterranean formations

International Nuclear Information System (INIS)

Sparlin, D.D.

1976-01-01

A sand-producing zone in a friable, unconsolidated sandstone formation traversed by a well bore is found by first introducing into the reservoir about 0.1--10 gallons of a radioactive mixture per foot of vertical formation being treated, the mixture containing about 0.1--1 lb of radioactive material per gallon of carrier fluid. A dispersing agent containing a deemulsifying surfactant may then be injected into the formation. The radioactivity in the well bore is recorded and the reservoir is returned to production. Another radioactivity log is run and a decrease in radioactivity indicates the location of the sand-producing portions of the formation

Formative Constructs Implemented via Common Factors

Science.gov (United States)

Treiblmaier, Horst; Bentler, Peter M.; Mair, Patrick

2011-01-01

Recently there has been a renewed interest in formative measurement and its role in properly specified models. Formative measurement models are difficult to identify, and hence to estimate and test. Existing solutions to the identification problem are shown to not adequately represent the formative constructs of interest. We propose a new two-step…

Seismic attributes and advanced computer algorithm to predict formation pore pressure: Qalibah formation of Northwest Saudi Arabia

Science.gov (United States)

Nour, Abdoulshakour M.

Oil and gas exploration professionals have long recognized the importance of predicting pore pressure before drilling wells. Pre-drill pore pressure estimation not only helps with drilling wells safely but also aids in the determination of formation fluids migration and seal integrity. With respect to the hydrocarbon reservoirs, the appropriate drilling mud weight is directly related to the estimated pore pressure in the formation. If the mud weight is lower than the formation pressure, a blowout may occur, and conversely, if it is higher than the formation pressure, the formation may suffer irreparable damage due to the invasion of drilling fluids into the formation. A simple definition of pore pressure is the pressure of the pore fluids in excess of the hydrostatic pressure. In this thesis, I investigated the utility of advance computer algorithm called Support Vector Machine (SVM) to learn the pattern of high pore pressure regime, using seismic attributes such as Instantaneous phase, t*Attenuation, Cosine of Phase, Vp/Vs ratio, P-Impedance, Reflection Acoustic Impedance, Dominant frequency and one well attribute (Mud-Weigh) as the learning dataset. I applied this technique to the over pressured Qalibah formation of Northwest Saudi Arabia. The results of my research revealed that in the Qalibah formation of Northwest Saudi Arabia, the pore pressure trend can be predicted using SVM with seismic and well attributes as the learning dataset. I was able to show the pore pressure trend at any given point within the geographical extent of the 3D seismic data from which the seismic attributes were derived. In addition, my results surprisingly showed the subtle variation of pressure within the thick succession of shale units of the Qalibah formation.

Consensus formation on coevolving networks: groups' formation and structure

International Nuclear Information System (INIS)

Kozma, Balazs; Barrat, Alain

2008-01-01

We study the effect of adaptivity on a social model of opinion dynamics and consensus formation. We analyse how the adaptivity of the network of contacts between agents to the underlying social dynamics affects the size and topological properties of groups and the convergence time to the stable final state. We find that, while on static networks these properties are determined by percolation phenomena, on adaptive networks the rewiring process leads to different behaviors: adaptive rewiring fosters group formation by enhancing communication between agents of similar opinion, though it also makes possible the division of clusters. We show how the convergence time is determined by the characteristic time of link rearrangement. We finally investigate how the adaptivity yields nontrivial correlations between the internal topology and the size of the groups of agreeing agents

Dioxin formation from waste incineration.

Science.gov (United States)

Shibamoto, Takayuki; Yasuhara, Akio; Katami, Takeo

2007-01-01

There has been great concern about dioxins-polychlorinated dibenzo dioxins (PCDDs), polychlorinated dibenzo furans (PCDFs), and polychlorinated biphenyls (PCBs)-causing contamination in the environment because the adverse effects of these chemicals on human health have been known for many years. Possible dioxin-contamination has received much attention recently not only by environmental scientists but also by the public, because dioxins are known to be formed during the combustion of industrial and domestic wastes and to escape into the environment via exhaust gases from incinerators. Consequently, there is a pressing need to investigate the formation mechanisms or reaction pathways of these chlorinated chemicals to be able to devise ways to reduce their environmental contamination. A well-controlled small-scale incinerator was used for the experiments in the core references of this review. These articles report the investigation of dioxin formation from the combustion of various waste-simulated samples, including different kinds of paper, various kinds of wood, fallen leaves, food samples, polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), polyvinylidene chloride, polyethylene tetraphthalate (PET), and various kinds of plastic products. These samples were also incinerated with inorganic chlorides (NaCl, KCl, CuCI2, MgCl2, MnCl2, FeCl2, CoCl2, fly ash, and seawater) or organic chlorides (PVC, chlordane, and pentachlorophenol) to investigate the role of chlorine content and/or the presence of different metals in dioxin formation. Some samples, such as newspapers, were burned after they were impregnated with NaCl or PVC, as well as being cocombusted with chlorides. The roles of incineration conditions, including chamber temperatures, O2 concentrations, and CO concentrations, in dioxin formation were also investigated. Dioxins (PCDDs, PCDFs, and coplanar-PCBs) formed in the exhaust gases from a controlled small-scale incinerator, where experimental waste

Teacher perspectives about using formative assessment

DEFF Research Database (Denmark)

Evans, Robert Harry; Clesham, Rose; Dolin, Jens

2018-01-01

This chapter examines three different classroom teacher perspectives when using ASSIST-ME project formative assessment methods as described in the introductory chapter. The first ‘teacher perspective’ is about changes in teacher self-efficacies while using formative assessment methods as monitored...... by a pre- and post-teacher questionnaire. Teachers who tried the unfamiliar formative methods of assessment (see introductory book chapter for these methods) as well as their colleagues who did not were surveyed. The second ‘teacher perspective’ examines changes in teachers’ subjective theories while...... trying project-specific formative assessment methods in Czech Republic. Analyses are done through case studies and interviews. The final part of the chapter looks at teacher perspectives while using an Internet-based application to facilitate formative assessment. The teacher use of the application...

COMPETENCYTHE FORMATION FOR LIFE

Directory of Open Access Journals (Sweden)

Milagros Mederos-Piñeiro

2016-07-01

Full Text Available The formation of life competences is the result of a quality education that prepares students to meet the challenges of a fast moving world where equality and equal opportunities should constitute premises of education; training them is a challenge teachers to assume new generations contribute actively to a better world. In Cuba are important research on the formation of communication competences and self-regulated learning in primary school. The paper shows the result of an investigation that provides a methodology for the formation of life competences in primary school education, used as an essential pathway research activity. The methodological approach of research has a quantitative approach and an explanatory scope to establish and make sense of understanding the causal relationship between the direction of research activity and training of life competences. Theoretical, empirical and mathematical-statistical, for characterizing the initial state, processing of results and analysis: research methods are used. The application of the methodology for the formation of life competences makes teachers lead the teaching-learning process with a research and transforming teaching concept, where the school is the protagonist of their learning and causes changes in their performances, which are evident in the formed competences related to effective and affective communication; the solution of problems related to life; the use of means in obtaining the knowledge and the expression of a behavior consistent with school and social demands. The effectiveness of the methodology confirms that there is a causal relationship between the direction of research activity by teachers and the formation of life competences in school.

The Physics of Planetesimal Formation

Science.gov (United States)

Simon, Jacob; Armitage, Philip; Youdin, Andrew; Li, Rixin

2015-12-01

Planetesimals are the precursors to planets, and understanding their formation is an essential step towards developing a complete theory of planet formation. For small solid particles (e.g., dust grains) to coagulate into planetesimals, however, requires that these particles grow beyond centimeter sizes; with traditional coagulation physics, this is very difficult. The streaming instability, which is a clumping process akin to the pile-up of cars in a traffic jam, generates sufficiently high solid densities that the mutual gravity between the clumped particles eventually causes their collapse towards planetesimal mass and size scales. Exploring this transition from dust grains to planetesimals is still in its infancy but is extremely important if we want to understand the basics of planet formation. Here, I present a series of high resolution, first principles numerical simulations of potoplanetary disk gas and dust to study the clumping of particles via the streaming instability and the subsequent collapse towards planetesimals. These simulations have been employed to characterize the planetesimal population as a function of radius in protoplanetary disks. The results of these simulations will be crucial for planet formation models to correctly explain the formation and configuration of solar systems.

Formation of galaxies

International Nuclear Information System (INIS)

Szalay, A.S.

1984-12-01

The present theories of galaxy formation are reviewed. The relation between peculiar velocities and the correlation function of galaxies points to the possibility that galaxies do not form uniformly everywhere. Scale invariant properties of the cluster-cluster correlations are discussed. Comparing the correlation functions in a dimensionless way, galaxies appear to be stronger clustered, in contrast with the comparison of the dimensional amplitudes of the correlation functions. Theoretical implications of several observations as Lyman-α clouds, correlations of faint galaxies are discussed. None of the present theories of galaxy formation can account for all facts in a natural way. 29 references

Formation temperatures of thermogenic and biogenic methane

Science.gov (United States)

Stolper, D.A.; Lawson, M.; Davis, C.L.; Ferreira, A.A.; Santos Neto, E. V.; Ellis, G.S.; Lewan, M.D.; Martini, Anna M.; Tang, Y.; Schoell, M.; Sessions, A.L.; Eiler, J.M.

2014-01-01

Methane is an important greenhouse gas and energy resource generated dominantly by methanogens at low temperatures and through the breakdown of organic molecules at high temperatures. However, methane-formation temperatures in nature are often poorly constrained. We measured formation temperatures of thermogenic and biogenic methane using a “clumped isotope” technique. Thermogenic gases yield formation temperatures between 157° and 221°C, within the nominal gas window, and biogenic gases yield formation temperatures consistent with their comparatively lower-temperature formational environments (<50°C). In systems where gases have migrated and other proxies for gas-generation temperature yield ambiguous results, methane clumped-isotope temperatures distinguish among and allow for independent tests of possible gas-formation models.

Process for fracturing underground formations

Energy Technology Data Exchange (ETDEWEB)

Kiel, O M

1974-01-25

This invention concerns a process for fracturing underground formations and has as one object the mixing of viscous compositions. Through a borehole, a fluid is injected into the formation. This fluid contains a complex prepared by the reaction of an aliphatic quaternary ammonium compound with a water-soluble compound chosen from monosaccharides, disaccharides, trisaccharides, polysaccharides, and synthetic hydroxylated polymers with long chains. These complexes are formed at temperatures between 20/sup 0/ and 205/sup 0/C. The process also includes production of formation fluid into the borehole.

AGN feedback in galaxy formation

CERN Document Server

Antonuccio-Delogu, Vincenzo

2010-01-01

During the past decade, convincing evidence has been accumulated concerning the effect of active galactic nuclei (AGN) activity on the internal and external environment of their host galaxies. Featuring contributions from well-respected researchers in the field, and bringing together work by specialists in both galaxy formation and AGN, this volume addresses a number of key questions about AGN feedback in the context of galaxy formation. The topics covered include downsizing and star-formation time scales in massive elliptical galaxies, the connection between the epochs of supermassive black h

Improving the Formatting Tools of CDS Invenio

CERN Document Server

Caffaro, J; Pu Faltings, Pearl

2006-01-01

CDS Invenio is the web-based integrated digital library system developed at CERN. It is a strategical tool that supports the archival and open dissemination of documents produced by CERN researchers. This paper reports on my Master’s thesis work done on BibFormat, a module in CDS Invenio, which formats documents metadata. The goal of this project was to implement a completely new formatting module for CDS Invenio. In this report a strong emphasis is put on the user-centered design of the new BibFormat. The bibliographic formatting process and its requirements are discussed. The task analysis and its resulting interaction model are detailed. The document also shows the implemented user interface of BibFormat and gives the results of the user evaluation of this interface. Finally the results of a small usability study of the formats included in CDS Invenio are discussed.

Formative (measurement)

NARCIS (Netherlands)

Fassott, G.; Henseler, Jörg; Cooper, C.; Lee, N.; Farrell, A.

2015-01-01

When using measurement models with multiple indicators, researchers need to decide about the epistemic relationship between the latent variable and its indicators. In this article, we describe the nature, the estimation, the characteristics, and the validity assessment of formative measurement

FORMATIVE ASSESSMENT IN EFL CLASSROOM PRACTICES

Directory of Open Access Journals (Sweden)

Ida Ayu Made Sri Widiastuti

2017-03-01

Full Text Available This study investigated the challenges and opportunities of formative assessment in EFL classes. It made use of qualitative research design by using indepth interviews to collect the required data. Three teachers and three students were involved as research participants in this study and they were intensively interviewed to get valid and reliable data regarding their understanding of formative assessment and the follow up actions they took after implementing formative assessment. The results of this study showed that the English teachers were found not to take appropriate follow up actions due to their low understanding of formative assessment. The teachers’ understanding could influence their ability in deciding the actions. This study indicates that EFL teachers need urgent further intensive training on the appropriate implementation of formative assessment and how follow up actions should be integrated into classroom practices

Formation Control for the MAXIM Mission

Science.gov (United States)

Luquette, Richard J.; Leitner, Jesse; Gendreau, Keith; Sanner, Robert M.

2004-01-01

Over the next twenty years, a wave of change is occurring in the space-based scientific remote sensing community. While the fundamental limits in the spatial and angular resolution achievable in spacecraft have been reached, based on today s technology, an expansive new technology base has appeared over the past decade in the area of Distributed Space Systems (DSS). A key subset of the DSS technology area is that which covers precision formation flying of space vehicles. Through precision formation flying, the baselines, previously defined by the largest monolithic structure which could fit in the largest launch vehicle fairing, are now virtually unlimited. Several missions including the Micro-Arcsecond X-ray Imaging Mission (MAXIM), and the Stellar Imager will drive the formation flying challenges to achieve unprecedented baselines for high resolution, extended-scene, interferometry in the ultraviolet and X-ray regimes. This paper focuses on establishing the feasibility for the formation control of the MAXIM mission. MAXIM formation flying requirements are on the order of microns, while Stellar Imager mission requirements are on the order of nanometers. This paper specifically addresses: (1) high-level science requirements for these missions and how they evolve into engineering requirements; and (2) the development of linearized equations of relative motion for a formation operating in an n-body gravitational field. Linearized equations of motion provide the ground work for linear formation control designs.

DNA methylation and memory formation.

Science.gov (United States)

Day, Jeremy J; Sweatt, J David

2010-11-01

Memory formation and storage require long-lasting changes in memory-related neuronal circuits. Recent evidence indicates that DNA methylation may serve as a contributing mechanism in memory formation and storage. These emerging findings suggest a role for an epigenetic mechanism in learning and long-term memory maintenance and raise apparent conundrums and questions. For example, it is unclear how DNA methylation might be reversed during the formation of a memory, how changes in DNA methylation alter neuronal function to promote memory formation, and how DNA methylation patterns differ between neuronal structures to enable both consolidation and storage of memories. Here we evaluate the existing evidence supporting a role for DNA methylation in memory, discuss how DNA methylation may affect genetic and neuronal function to contribute to behavior, propose several future directions for the emerging subfield of neuroepigenetics, and begin to address some of the broader implications of this work.

Robust Decentralized Formation Flight Control

Directory of Open Access Journals (Sweden)

Zhao Weihua

2011-01-01

Full Text Available Motivated by the idea of multiplexed model predictive control (MMPC, this paper introduces a new framework for unmanned aerial vehicles (UAVs formation flight and coordination. Formulated using MMPC approach, the whole centralized formation flight system is considered as a linear periodic system with control inputs of each UAV subsystem as its periodic inputs. Divided into decentralized subsystems, the whole formation flight system is guaranteed stable if proper terminal cost and terminal constraints are added to each decentralized MPC formulation of the UAV subsystem. The decentralized robust MPC formulation for each UAV subsystem with bounded input disturbances and model uncertainties is also presented. Furthermore, an obstacle avoidance control scheme for any shape and size of obstacles, including the nonapriorily known ones, is integrated under the unified MPC framework. The results from simulations demonstrate that the proposed framework can successfully achieve robust collision-free formation flights.

Formation of tax culture in Russia

Directory of Open Access Journals (Sweden)

Halikova Je.A.

2014-11-01

Full Text Available This article deals with the mechanism of the formation of tax culture in Russia, moral and ethical principles, on which based the work of the tax authorities, given the author's idea of the formation of tax culture. We consider the institution of tax advice, its interaction with the tax authorities and its impact on the formation of tax culture.

Making the invisible visible: improved electrospray ion formation of metalloporphyrins/-phthalocyanines by attachment of the formate anion (HCOO(-)).

Science.gov (United States)

Hitzenberger, Jakob Felix; Dammann, Claudia; Lang, Nina; Lungerich, Dominik; García-Iglesias, Miguel; Bottari, Giovanni; Torres, Tomás; Jux, Norbert; Drewello, Thomas

2016-02-21

A protocol is developed for the coordination of the formate anion (HCOO(-)) to neutral metalloporphyrins (Pors) and -phthalocyanines (Pcs) containing divalent metals as a means to improve their ion formation in electrospray ionization (ESI). This method is particularly useful when the oxidation of the neutral metallomacrocycle fails. While focusing on Zn(II)Pors and Zn(II)Pcs, we show that formate is also readily attached to Mn(II), Mg(II) and Co(II)Pcs. However, for the Co(II)Pc secondary reactions can be observed. Upon collision-induced dissociation (CID), Zn(II)Por/Pc·formate supramolecular complexes can undergo the loss of CO2 in combination with transfer of a hydride anion (H(-)) to the zinc metal center. Further dissociation leads to electron transfer and hydrogen atom loss, generating a route to the radical anion of the Zn(II)Por/Pc without the need for electrochemical reduction, although the Zn(II)Por/Pc may have a too low electron affinity to allow electron transfer directly from the formate anion. In addition to single Por molecules, multi Por arrays were successfully analyzed by this method. In this case, multiple addition of formate occurs, giving rise to multiply charged species. In these multi Por arrays, complexation of the formate anion occurs by two surrounding Por units (sandwich). Therefore, the maximum attainment of formate anions in these arrays corresponds to the number of such sandwich complexes rather than the number of porphyrin moieties. The same bonding motif leads to dimers of the composition [(Zn(II)Por/Pc)2·HCOO](-). In these, the formate anion can act as a structural probe, allowing the distinction of isomeric ions with the formate bridging two macrocycles or being attached to a dimer of directly connected macrocycles.

Maggot excretions inhibit biofilm formation on biomaterials.

Science.gov (United States)

Cazander, Gwendolyn; van de Veerdonk, Mariëlle C; Vandenbroucke-Grauls, Christina M J E; Schreurs, Marco W J; Jukema, Gerrolt N

2010-10-01

Biofilm-associated infections in trauma surgery are difficult to treat with conventional therapies. Therefore, it is important to develop new treatment modalities. Maggots in captured bags, which are permeable for larval excretions/secretions, aid in healing severe, infected wounds, suspect for biofilm formation. Therefore we presumed maggot excretions/secretions would reduce biofilm formation. We studied biofilm formation of Staphylococcus aureus, Staphylococcus epidermidis, Klebsiella oxytoca, Enterococcus faecalis, and Enterobacter cloacae on polyethylene, titanium, and stainless steel. We compared the quantities of biofilm formation between the bacterial species on the various biomaterials and the quantity of biofilm formation after various incubation times. Maggot excretions/secretions were added to existing biofilms to examine their effect. Comb-like models of the biomaterials, made to fit in a 96-well microtiter plate, were incubated with bacterial suspension. The formed biofilms were stained in crystal violet, which was eluted in ethanol. The optical density (at 595 nm) of the eluate was determined to quantify biofilm formation. Maggot excretions/secretions were pipetted in different concentrations to (nonstained) 7-day-old biofilms, incubated 24 hours, and finally measured. The strongest biofilms were formed by S. aureus and S. epidermidis on polyethylene and the weakest on titanium. The highest quantity of biofilm formation was reached within 7 days for both bacteria. The presence of excretions/secretions reduced biofilm formation on all biomaterials. A maximum of 92% of biofilm reduction was measured. Our observations suggest maggot excretions/secretions decrease biofilm formation and could provide a new treatment for biofilm formation on infected biomaterials.

Method of developing thick sloping coal formations

Energy Technology Data Exchange (ETDEWEB)

Bragintsev, V F; Mashkovtsev, I L; Semenov, V S; Zykov, V N

1980-04-25

A method is patented for developing thick sloping coal formations in 3 inclined layers. It includes conducting developmental operations for each of the layers until one begins the last one and extraction of the layers. In order to improve effectivess and extraction operation safety one first carried out preliminary development of a formation in thin strips beneath protected objects when extracting formation which contain alot of gas. Then one removes the gas of a formation through boreholes that have been drilled into the formation from the indicated workings. Then one works the upper layer in thin strips in a sequence from the roof of the formation to the floor of the upper layer. The one strengthens roof rock of the formation by pumping in a quickly hardening solution into the boreholes which have been drilled into the roof of the formation after processing the upper layer. The middle layer is worked in thin strips in the sequence from the roof to the ground of the middle layer, then the lower layer of the formation is strengthened by pumping in quickly hardening solution into the formation along degasified boreholes and it is worked in thin strips in sequence from the ground of the lower to its roof. Workings are shaped respectively for the middle and lower layers by deepening workings of the upper and middle layers. The layers are worked respectively after finishing displacement of the roof in front of the extraction face of each subsequent extraction of a layer in alternating fashion.

Insights from simulations of star formation

International Nuclear Information System (INIS)

Larson, Richard B

2007-01-01

Although the basic physics of star formation is classical, numerical simulations have yielded essential insights into how stars form. They show that star formation is a highly nonuniform runaway process characterized by the emergence of nearly singular peaks in density, followed by the accretional growth of embryo stars that form at these density peaks. Circumstellar discs often form from the gas being accreted by the forming stars, and accretion from these discs may be episodic, driven by gravitational instabilities or by protostellar interactions. Star-forming clouds typically develop filamentary structures, which may, along with the thermal physics, play an important role in the origin of stellar masses because of the sensitivity of filament fragmentation to temperature variations. Simulations of the formation of star clusters show that the most massive stars form by continuing accretion in the dense cluster cores, and this again is a runaway process that couples star formation and cluster formation. Star-forming clouds also tend to develop hierarchical structures, and smaller groups of forming objects tend to merge into progressively larger ones, a generic feature of self-gravitating systems that is common to star formation and galaxy formation. Because of the large range of scales and the complex dynamics involved, analytic models cannot adequately describe many aspects of star formation, and detailed numerical simulations are needed to advance our understanding of the subject. 'The purpose of computing is insight, not numbers.' Richard W Hamming, in Numerical Methods for Scientists and Engineers (1962) 'There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.' William Shakespeare, in Hamlet, Prince of Denmark (1604) (key issues review)

Insights from simulations of star formation

Energy Technology Data Exchange (ETDEWEB)

Larson, Richard B [Department of Astronomy, Yale University, Box 208101, New Haven, CT 06520-8101 (United States)

2007-03-15

Although the basic physics of star formation is classical, numerical simulations have yielded essential insights into how stars form. They show that star formation is a highly nonuniform runaway process characterized by the emergence of nearly singular peaks in density, followed by the accretional growth of embryo stars that form at these density peaks. Circumstellar discs often form from the gas being accreted by the forming stars, and accretion from these discs may be episodic, driven by gravitational instabilities or by protostellar interactions. Star-forming clouds typically develop filamentary structures, which may, along with the thermal physics, play an important role in the origin of stellar masses because of the sensitivity of filament fragmentation to temperature variations. Simulations of the formation of star clusters show that the most massive stars form by continuing accretion in the dense cluster cores, and this again is a runaway process that couples star formation and cluster formation. Star-forming clouds also tend to develop hierarchical structures, and smaller groups of forming objects tend to merge into progressively larger ones, a generic feature of self-gravitating systems that is common to star formation and galaxy formation. Because of the large range of scales and the complex dynamics involved, analytic models cannot adequately describe many aspects of star formation, and detailed numerical simulations are needed to advance our understanding of the subject. 'The purpose of computing is insight, not numbers.' Richard W Hamming, in Numerical Methods for Scientists and Engineers (1962) 'There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.' William Shakespeare, in Hamlet, Prince of Denmark (1604) (key issues review)

Galaxy formation and evolution

CERN Document Server

Mo, Houjun; White, Simon

2010-01-01

The rapidly expanding field of galaxy formation lies at the interface between astronomy, particle physics, and cosmology. Covering diverse topics from these disciplines, all of which are needed to understand how galaxies form and evolve, this book is ideal for researchers entering the field. Individual chapters explore the evolution of the Universe as a whole and its particle and radiation content; linear and nonlinear growth of cosmic structure; processes affecting the gaseous and dark matter components of galaxies and their stellar populations; the formation of spiral and elliptical galaxies; central supermassive black holes and the activity associated with them; galaxy interactions; and the intergalactic medium. Emphasizing both observational and theoretical aspects, this book provides a coherent introduction for astronomers, cosmologists, and astroparticle physicists to the broad range of science underlying the formation and evolution of galaxies.

Output formatting in Apple-Soft Basic

International Nuclear Information System (INIS)

Navale, A.S.

1987-01-01

Personal computers are being used extensively in various fields. BASIC is a very popular and widely used language in personal computers. Apple computer is one of the popular machines used for scientific and engineering applications. Presenting output from computers in a neat and easy to read form is very important. Languages like FORTRAN have utility command 'FORMAT' which takes care of the formatting of the output in user-defined form. In some versions of BASIC a PRINT USING facility is available but it is not as powerful as the FORTRAN statement 'FORMAT'. Applesoft basic does not have even this PRINT USING command. Programmers have to write their own program segments to handle output formatting in Applesoft BASIC. Generally, such user written programs are of limited use as they cannot be used easily with other programs. A general purpose and easily transportable subroutine in Applesoft BASIC is presented here for handling output formatting in user-defined structure. The subroutine is nearly as powerful as the FORMAT statement in FORTRAN. It can also be used in other versions of BASIC with very little modifications. 3 tables, 4 refs. (author)

Heating tar sands formations while controlling pressure

Science.gov (United States)

Stegemeier, George Leo [Houston, TX; Beer, Gary Lee [Houston, TX; Zhang, Etuan [Houston, TX

2010-01-12

Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. A pressure in the majority of the section may be maintained below a fracture pressure of the formation. The pressure in the majority of the section may be reduced to a selected pressure after the average temperature reaches a temperature that is above 240.degree. C. and is at or below pyrolysis temperatures of hydrocarbons in the section. At least some hydrocarbon fluids may be produced from the formation.

Formation of the oil composition of the Yu0 Bazhenov formation, Salym oil field

Directory of Open Access Journals (Sweden)

E.V. Soboleva

2017-05-01

Full Text Available The Bazhenov horizon of Western Siberia has been studied in considerable detail from different perspectives and different methods, a large number of studies have been devoted to a wide range of issues related to the lithological composition of rocks, their reservoir properties, the study of organic matter, properties and composition of oil at various analytical levels, and many others. This work is devoted to restoring conditions for the formation of oil properties and composition of the Yu0 Salym oil field, based mainly on the geochemical aspects of the study of oil changes both in area and in the section within the productive layer of Salym structure, using some geological data, such as structural plan for the reflecting horizon B (the roof of the Bazhenov formation, having a complex configuration, reservoir temperatures and pressure, well flow rates, and others. There is no single reservoir at the Salym field in the Yu0 formation. For the conclusions of the geological-geochemical interpretation, a sampling of 61 samples of oil from exploration, appraisal and production wells of the initial stages of production was used, since in the future when oil is extracted, the ecology in the deposits changes, and 21 samples of oil from other fields in the West Siberian oil and gas basin. Conventionally, three types of oils are distinguished, differing in their physicochemical parameters, group hydrocarbon and molecular composition. It was suggested that in addition to the own organic matter of the Bazhenov formation, hydrocarbon fluids of the Vasyugan, Tyumen formations and possibly Paleozoic rocks were involved in the formation of the oil composition. The flow of light liquid hydrocarbons and gases occurred along the zones of faults of different genesis and duration of existence.

Variation of radiation sensitivity of Friend Erythroleukemia cells cultured in the presence of the differentiation inducer DMSO

International Nuclear Information System (INIS)

Einspenner, M.; Boulton, J.E.; Borsa, J.

1984-01-01

Differentiation of Friend erythroleukemia cells (FELC) was induced with 1.5% dimethyl sulfoxide (DMSO) in the culture medium. Cell growth, erythroid differentiation, and radiosensitivity of the proliferative capacity of the cells were measured and compared to a noninduced control culture of identical age. Induced cells first appeared on Day 2 after DMSO addition, and increased to a maximum of 80 to 90% of the cell population on Day 5, whereas in the control culture, induction was less than 2% of the cells. Radiosensitivity of the cells in the induced culture relative to that of cells in the control culture, showed an age-dependent variation. On days 1 and 2 after DMSO addition, the cells in the induced culture were less radiosensitive than those in the control culture. At later times, this relationship was reversed, and between days 3 and 5 the clonable cells in the induced culture were less radiosensitive than those in the control culture. These results suggest that the metabolic events associated with commitment of FELC to differentiate affect their ability to cope with the radiation-induced lesions underlying the loss of division capacity

Biological assessment of the enhancement of tritium excretion by administration of diuretics and excessive water in mice

International Nuclear Information System (INIS)

Kunugita, Naoki; Dohi, Seitaro; Yamamoto, Hisao; Norimura, Toshiyuki; Tsuchiya, Takehiko

1990-01-01

This study was undertaken to determine whether or not the administration of diuretics and excess water after tritium exposure would have any positive reducing effect not only on the retention of tritium but also on the radiation damage of hematopoietic tissue in mice. When mice were treated with diuretics and excess water for a few days after injection of tritiated water (HTO), radioactivity within the body fluid and tissues was reduced, and the number of colony-forming units (CFU-s), clonability of splenic T cells and proliferative activity assayed by Concanavalin-A blastogenesis were increased in comparison with those in the controls. When the mice were injected with a large dose of HTO (811 MBq/mouse) to assay survival, no mice treated with diuretic and excess water died 80 days after injection, while 80% of the controls died during the first month. The final committed dose in the mice treated early with diuretics was calculated to be 60% of that in the controls. These results suggest that treatment with diuretics and excess water is useful for practical purposes when a human is accidentally exposed to tritium. (author)

Biological assessment of the enhancement of tritium excretion by administration of diuretics and excessive water in mice

Energy Technology Data Exchange (ETDEWEB)

Kunugita, Naoki; Dohi, Seitaro; Yamamoto, Hisao; Norimura, Toshiyuki; Tsuchiya, Takehiko (University of Occupational and Environmental Health, Kitakyushu (Japan))

1990-12-01

This study was undertaken to determine whether or not the administration of diuretics and excess water after tritium exposure would have any positive reducing effect not only on the retention of tritium but also on the radiation damage of hematopoietic tissue in mice. When mice were treated with diuretics and excess water for a few days after injection of tritiated water (HTO), radioactivity within the body fluid and tissues was reduced, and the number of colony-forming units (CFU-s), clonability of splenic T cells and proliferative activity assayed by Concanavalin-A blastogenesis were increased in comparison with those in the controls. When the mice were injected with a large dose of HTO (811 MBq/mouse) to assay survival, no mice treated with diuretic and excess water died 80 days after injection, while 80% of the controls died during the first month. The final committed dose in the mice treated early with diuretics was calculated to be 60% of that in the controls. These results suggest that treatment with diuretics and excess water is useful for practical purposes when a human is accidentally exposed to tritium. (author).

The Road to Galaxy Formation

CERN Document Server

Keel, William C

2007-01-01

The formation of galaxies is one of the greatest puzzles in astronomy, the solution is shrouded in the depths of space and time, but has profound implications for the universe we observe today. The book discusses the beginnings of the process from cosmological observations and calculations, considers the broad features of galaxies that we need to explain and what we know of their later history. The author compares the competing theories for galaxy formation and considers the progress expected from new generations of powerful telescopes both on earth and in space. In this second edition the author has retained the observationally-based approach of the first edition, a feature which was particularly well-reviewed: Writing in Nature, Carlton Baugh noted in February 2003 that “It is refreshing, in a market dominated by theorists, to come across a book on galaxy formation written from an observational perspective. The Road to Galaxy Formation should prove to be a handy primer on observations for graduate student...

Formation aux TICE des formateurs d’enseignants : un tissage entre formation et autoformation

Directory of Open Access Journals (Sweden)

Pierre-François Coen

2012-01-01

Full Text Available Cette recherche exploratoire rend compte des modalités de formation des formateurs d’enseignants dans deux établissements d’enseignement du canton de Fribourg, en Suisse. Neuf formateurs d’enseignants ont été interrogés sur leurs parcours de formation et d’autoformation en matière de compétences technologiques et d’intégration des TICE. Les résultats montrent que, même si ces formateurs ont acquis des compétences technologiques, les dispositifs d’enseignement-apprentissage qu’ils mettent en place pour former de futurs enseignants intègrent relativement peu les TICE. En outre, les propos tenus montrent que les formateurs déploient des stratégies d’autoformation plus ou moins efficaces et coûteuses en temps pour les aspects techniques, mais n’usent presque jamais de ce type de procédé pour développer une intégration pédagogique des TICE dans leurs cours. La fin de l’article reprend ces éléments et les discute en essayant de présenter quelques pistes en articulant formation formelle et informelle dans le contexte de la formation des enseignants.

Current status of radioligand antibodies in the treatment of malignancy

International Nuclear Information System (INIS)

Maners, A.W.; Sanders, M.M.; Pappas, A.A.

1988-01-01

Monoclonal anti-tumor antibodies labeled with a radioactive moiety present an exciting new approach to cancer therapy. With the advent of hybridoma technology, monoclonal antibodies can now be produced in quantity. Indeed, antibodies against tumor-related and tumor-specific antigens have been produced, labeled with a radioactive substance, and used therapeutically. The rationale for this therapeutic approach and the results of human clinical trials will be reported herein.27 references

Purpose-Oriented Antibody Libraries Incorporating Tailored CDR3 Sequences

OpenAIRE

Bonvin, Pauline; Venet, Sophie; Kosco-Vilbois, Marie; Fischer, Nicolas

2015-01-01

The development of in vitro antibody selection technologies has allowed overcoming some limitations inherent to the hybridoma technology. In most cases, large repertoires of antibody genes have been assembled to create highly diversified libraries allowing the isolation of antibodies recognizing virtually any antigen. However, these universal libraries might not allow the isolation of antibodies with specific structural properties or particular amino acid contents that are rarely found in nat...

Processes and problems in secondary star formation

International Nuclear Information System (INIS)

Klein, R.I.; Whitaker, R.W.; Sandford, M.T. II.

1984-03-01

Recent developments relating the conditions in molecular clouds to star formation triggered by a prior stellar generation are reviewed. Primary processes are those that lead to the formation of a first stellar generation. The secondary processes that produce stars in response to effects caused by existing stars are compared and evaluated in terms of the observational data presently available. We discuss the role of turbulence to produce clumpy cloud structures and introduce new work on colliding inter-cloud gas flows leading to non-linear inhomogeneous cloud structures in an intially smooth cloud. This clumpy morphology has important consequences for secondary formation. The triggering processes of supernovae, stellar winds, and H II regions are discussed with emphasis on the consequences for radiation driven implosion as a promising secondary star formation mechanism. Detailed two-dimensional, radiation-hydrodynamic calculations of radiation driven implosion are discussed. This mechanism is shown to be highly efficient in synchronizing the formation of new stars in congruent to 1-3 x 10 4 years and could account for the recent evidence for new massive star formation in several UCHII regions. It is concluded that, while no single theory adequately explains the variety of star formation observed, a uniform description of star formation is likely to involve several secondary processes. Advances in the theory of star formation will require multiple dimensional calculations of coupled processes. The important non-linear interactions include hydrodynamics, radiation transport, and magnetic fields

Processes and problems in secondary star formation

International Nuclear Information System (INIS)

Klein, R.I.; Whitaker, R.W.; Sandford, M.T. II

1985-01-01

Recent developments relating the conditions in molecular clouds to star formation triggered by a prior stellar generation are reviewed. Primary processes are those that lead to the formation of a first stellar generation. The secondary processes that produce stars in response to effects caused by existing stars are compared and evaluated in terms of observational data presently available. We discuss the role of turbulence to produce clumpy cloud structures and introduce new work on colliding intercloud gas flows leading to nonlinear inhomogeneous cloud structures in an initially smooth cloud. This clumpy morphology has important consequences for secondary formation. The triggering processes of supernovae, stellar winds, and H II regions are discussed with emphasis on the consequences for radiation-driven implosion as a promising secondary star formation mechanism. Detailed two-dimensional, radiation-hydrodynamic calculations of radiation-driven implosion are discussed. This mechanism is shown to be highly efficient in synchronizing the formation of new stars in -- 1-3 x 10/sup 4/ yr and could account for the recent evidence for new massive star formation in several ultracompact H II regions. It is concluded that, while no single theory adequately explains the variety of star formation observed, a uniform description of star formation is likely to involve several secondary processes. Advances in the theory of star formation will require multi-dimensional calculations of coupled processes. Important nonlinear interactions include hydrodynamics, radiation transport, and magnetic fields

Professional Development through Formative Evaluation

Science.gov (United States)

Nsibande, Rejoice; Garraway, James

2011-01-01

Formative evaluation and its associated methodology of reflection on practice are used extensively in academic staff development. In reflecting on formative evaluation processes in both more traditional and newer programmes conducted at a university of technology, a number of variables reported in the literature were observed to have influenced…

Analysis of constituents of earth formations

International Nuclear Information System (INIS)

Hertzog, R.C.; Grau, J.A.

1981-01-01

The composition of an earth formation is investigated by repetitively irradiating the formation with bursts of neutrons from a source and measuring an energy spectrum of the scattering gamma rays resulting from such irradiation e.g. by photomultiplier or solid state detector. The measured spectrum is thereafter analyzed by comparing it with a composite spectrum, made up of standard spectra, measured in a controlled environment, of constituents postulated to comprise the formation. As a result of such analysis, the proportions of the postulated constituents in the formation are determined. Since the measured spectrum is subject to degradation due to changes in the resolution of the detector, a filtering arrangement effects modification of the standard spectra in a manner which compensates for the changes in the detector and thereby provides for a more accurate determination of the constituents of the formation. Temperature is measured by sensor to compensate for temperature dependence of detector resolution. (author)

Transient Exciplex Formation Electron Transfer Mechanism

OpenAIRE

Michael G. Kuzmin; Irina V. Soboleva; Elena V. Dolotova

2011-01-01

Transient exciplex formation mechanism of excited-state electron transfer reactions is analyzed in terms of experimental data on thermodynamics and kinetics of exciplex formation and decay. Experimental profiles of free energy, enthalpy, and entropy for transient exciplex formation and decay are considered for several electron transfer reactions in various solvents. Strong electronic coupling in contact pairs of reactants causes substantial decrease of activation energy relative to that for c...

Regulation of Reactionary Dentine Formation.

Science.gov (United States)

Neves, V C M; Sharpe, P T

2018-04-01

During the treatment of dental caries that has not penetrated the tooth pulp, maintenance of as much unaffected dentine as possible is a major goal during the physical removal of decayed mineral. Damage to dentine leads to release of fossilized factors (transforming growth factor-β [TGF-β] and bone morphogenic protein [BMP]) in the dentine that are believed to stimulate odontoblasts to secrete new "tertiary" dentine (reactionary dentine). This is formed on the pulpal surface of existing dentine and rethickens the dentine. We have previously shown that activation of Wnt/β-catenin signaling is pivotal for tooth repair in exposed pulp injury, and the pathway can be activated by small-molecule GSK-3 antagonists, resulting in enhanced reparative dentine formation. Here, we use a nonexposed pulp injury model to investigate the mechanisms of reactionary dentine formation in vivo, using small molecules to modulate the Wnt/β-catenin, TGF-β, and BMP pathways. We found that a local increase of Wnt activation at the injury site enhances reactionary dentine secretion. In addition, inhibition of TGF-β, BMP, or Wnt pathways does not impede reactionary dentine formation, although inhibition of TGF-β and/or BMP signaling does result in more disorganized, nontubular reactionary dentine. This suggests that Wnt/β-catenin signaling plays no major role in the formation of reactionary dentine, but in common with reparative dentine formation, exogenous elevation of Wnt/β-catenin signaling can enhance tertiary dentine formation. Release of latent TGF-β or BMPs from dentine is not required for the deposition of mineral to form reactionary dentine but does play a role in its organization.

{alpha}-Man monolayer formation via Si-C bond formation and protein recognition

Energy Technology Data Exchange (ETDEWEB)

Funato, Koji [School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292 (Japan); Shirahata, Naoto [National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Miura, Yoshiko, E-mail: miuray@jaist.ac.j [School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292 (Japan)

2009-11-30

An acetylenyl-terminated saccharide was synthesized and the thin layer formation on the hydrogen-terminated silicon was investigated. The acetylenyl-terminated saccharide was synthesized by the condensation reaction of hexynoic acid and p-aminophenyl saccharide. This was reacted with hydrogen-terminated silicon (Si-H) by a photochemical reaction. The resulting saccharide modified substrate was analyzed by ellipsometry and X-ray photoelectron spectroscopy, which showed the formation of a uniform monolayer. The surface's ability to recognize proteins was analyzed by fluorescent microscopy, and showed specific interactions with sugar recognition proteins.

Inside-out planet formation

International Nuclear Information System (INIS)

Chatterjee, Sourav; Tan, Jonathan C.

2014-01-01

The compact multi-transiting planet systems discovered by Kepler challenge planet formation theories. Formation in situ from disks with radial mass surface density, Σ, profiles similar to the minimum mass solar nebula but boosted in normalization by factors ≳ 10 has been suggested. We propose that a more natural way to create these planets in the inner disk is formation sequentially from the inside-out via creation of successive gravitationally unstable rings fed from a continuous stream of small (∼cm-m size) 'pebbles', drifting inward via gas drag. Pebbles collect at the pressure maximum associated with the transition from a magnetorotational instability (MRI)-inactive ('dead zone') region to an inner MRI-active zone. A pebble ring builds up until it either becomes gravitationally unstable to form an ∼1 M ⊕ planet directly or induces gradual planet formation via core accretion. The planet may undergo Type I migration into the active region, allowing a new pebble ring and planet to form behind it. Alternatively, if migration is inefficient, the planet may continue to accrete from the disk until it becomes massive enough to isolate itself from the accretion flow. A variety of densities may result depending on the relative importance of residual gas accretion as the planet approaches its isolation mass. The process can repeat with a new pebble ring gathering at the new pressure maximum associated with the retreating dead-zone boundary. Our simple analytical model for this scenario of inside-out planet formation yields planetary masses, relative mass scalings with orbital radius, and minimum orbital separations consistent with those seen by Kepler. It provides an explanation of how massive planets can form with tightly packed and well-aligned system architectures, starting from typical protoplanetary disk properties.

Recognizing team formation in american football

KAUST Repository

Atmosukarto, Indriyati

2014-01-01

Most existing software packages for sports video analysis require manual annotation of important events in the video. Despite being the most popular sport in the United States, most American football game analysis is still done manually. Line of scrimmage and offensive team formation recognition are two statistics that must be tagged by American Football coaches when watching and evaluating past play video clips, a process which takesmanyman hours per week. These two statistics are the building blocks for more high-level analysis such as play strategy inference and automatic statistic generation. In this chapter, we propose a novel framework where given an American football play clip, we automatically identify the video frame in which the offensive team lines in formation (formation frame), the line of scrimmage for that play, and the type of player formation the offensive team takes on. The proposed framework achieves 95% accuracy in detecting the formation frame, 98% accuracy in detecting the line of scrimmage, and up to 67%accuracy in classifying the offensive team’s formation. To validate our framework, we compiled a large dataset comprising more than 800 play-clips of standard and high definition resolution from real-world football games. This dataset will be made publicly available for future comparison.

STAR FORMATION IN DISK GALAXIES. II. THE EFFECT OF STAR FORMATION AND PHOTOELECTRIC HEATING ON THE FORMATION AND EVOLUTION OF GIANT MOLECULAR CLOUDS

International Nuclear Information System (INIS)

Tasker, Elizabeth J.

2011-01-01

We investigate the effect of star formation and diffuse photoelectric heating on the properties of giant molecular clouds (GMCs) formed in high-resolution (∼ H,c >100 cm -3 are identified as GMCs. Between 1000 and 1500 clouds are created in the simulations with masses M>10 5 M sun and 180-240 with masses M>10 6 M sun in agreement with estimates of the Milky Way's population. We find that the effect of photoelectric heating is to suppress the fragmentation of the interstellar medium, resulting in a filamentary structure in the warm gas surrounding clouds. This environment suppresses the formation of a retrograde rotating cloud population, with 88% of the clouds rotating prograde with respect to the galaxy after 300 Myr. The diffuse heating also reduces the initial star formation rate (SFR), slowing the conversation of gas into stars. We therefore conclude that the interstellar environment plays an important role in the GMC evolution. Our clouds live between 0 and 20 Myr with a high infant mortality (t' < 3 Myr) due to cloud mergers and star formation. Other properties, including distributions of mass, size, and surface density, agree well with observations. Collisions between our clouds are common, occurring at a rate of ∼ 1/4 of the orbital period. It is not clear whether such collisions trigger or suppress star formation at our current resolution. Our SFR is a factor of 10 higher than observations in local galaxies. This is likely due to the absence of localized feedback in our models.

Aggregate formation in 3D turbulent-like flows

NARCIS (Netherlands)

Dominguez, A.; Aartrijk, van M.; Castello, Del L.; Clercx, H.J.H.; Geurts, B.; Clercx, H

2006-01-01

Aggregate formation is an important process in industrial and environ mental turbulent flows. Two examples in the environmental area, where turbulent aggregate formation takes place, are raindrop formation in clouds and Marine Snow (aggregate) formation in the upper layer in the oceans. The

Chlorination and chloramines formation

International Nuclear Information System (INIS)

Yee, Lim Fang; Mohd Pauzi Abdullah; Sadia Ata; Abbas Abdullah; Basar IShak; Khairul Nidzham

2008-01-01

Chlorination is the most important method of disinfection in Malaysia which aims at ensuring an acceptable and safe drinking water quality. The dosing of chlorine to surface water containing ammonia and nitrogen compounds may form chloramines in the treated water. During this reaction, inorganic and organic chloramines are formed. The recommended maximum acceptable concentration (MAC) for chloramines in drinking water is 3000 μg/L. The production of monochloramine, dichloramine and trichloramine is highly dependent upon pH, contact time and the chlorine to ammonia molar ratio. The purpose of this study is to examine the formation of chloramines that occur upon the chlorination during the treatment process. Chloramines were determined using the N,N-diethyl-p-phenylenediamine (DPD) colorimetric method. The influences of ammonia, pH and chlorine dosage on the chloramines formation were also studied. This paper presents a modeling approach based on regression analysis which is designed to estimate the formation of chloramines. The correlation between the concentration of chloramines and the ammonia, pH and chlorine dosage was examined. In all cases, the quantity of chloramines formed depended linearly upon the amount of chlorine dosage. On the basis of this study it reveals that the concentration of chloramines is a function of chlorine dosage and the ammonia concentration to the chlorination process. PH seems to not significantly affect the formation of chloramines. (author)

Flowchart-format emergency operating procedures-strengths and weaknesses

International Nuclear Information System (INIS)

Barnes, V.E.; Bongarra, J.P. Jr.

1989-01-01

An increasing number of nuclear power plant licensees are converting their text-format emergency operating procedures (EOPs) to flowcharts. Findings of a recent study of the flowchart-format EOPs indicate that the flowchart format appears to solve several significant usability problems associated with text-format EOPs, but also introduces other types of usability concerns. This paper discusses some of the strengths and weaknesses of the flowchart format for presenting EOPs

Formation Number Of Laminar Vortex Rings. Numerical Simulations

International Nuclear Information System (INIS)

Rosenfeld, M.; Rambod, E.; Gharib, M.

1998-01-01

The formation time scale of axisymmetric vortex rings is studied numerically for relatively long discharge times. Experimental findings on the existence and universality of a formation time scale, referred to as the formation number, are confirmed. The formation number is indicative of the time a vortex ring acquires its maximal circulation. For vortex rings generated by impulsive motion of a piston, the formation number was found experimentally to be approximately 4. Numerical extension of the experimental study to thick shear layers indicates that the scaled circulation of the pinched-off vortex is relatively insensitive of the details of the formation process, such as the velocity program, velocity profile or vortex generator geometry. In contrast, the formation number does depend on the velocity profile

Portable File Format (PFF) specifications

Energy Technology Data Exchange (ETDEWEB)

Dolan, Daniel H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-02-01

Created at Sandia National Laboratories, the Portable File Format (PFF) allows binary data transfer across computer platforms. Although this capability is supported by many other formats, PFF files are still in use at Sandia, particularly in pulsed power research. This report provides detailed PFF specifications for accessing data without relying on legacy code.

Satellite Formation Control Using Atmospheric Drag

National Research Council Canada - National Science Library

Hajovsky, Blake B

2007-01-01

This study investigates the use of a linear quadratic terminal controller to reconfigure satellite formations using atmospheric drag actuated control while minimizing the loss of energy of the formation...

Formation and elution of toxic compounds from sterilized medical products: toxic compound formation from irradiated products

International Nuclear Information System (INIS)

Shintani, Hideharu

1996-01-01

No formation of MDA was observed in chain-extended thermoplastic polyurethane (PU) when sterilized by autoclave or γ-ray irradiation. No formation of MDA was observed in nonchain-extended thermoplastic PU when sterilized by γ-ray irradiation. Less than 1 ppm MDA was produced in nonchain-extended thermoplastic PU sterilized by autoclave sterilization. Autoclave sterilization did not produce MDA in thermosetting PU potting material. MDA formation in potting material was promoted by γ-irradiation and increased with increasing irradiation at a quadratic equation of regression. MDA formation at 100 kGy irradiation is a few ppm and < 1 ppm at 25kGy irradiation, therefore the potential risk to human recipients was not significant. The elution of compounds other than MDA from potting material was more problematic. Solvent extracts from potting material presented mutagenicity in the absence of metabolic activity. MDA presented mutagenicity in the presence of metabolic activity, therefore MDA was not the mutagenic trigger. The chemical and biological characteristics of the specific mutagens required to identify in a further study. Negative promotion of MDA formation and a less presence of mutagen in autoclave sterilized potting material indicated that autoclave sterilization was preferable. (Author)

Formation and behaviour of organic iodine

International Nuclear Information System (INIS)

Zilliacus, R.; Koukkar, P.; Karjunen, T.; Sjoevall, H.

2002-01-01

The report presents experimental studies on the formation of organic iodine in severe reactor accidents. The analyses were performed to evaluate the amount of alkaline chemical needed for effective pH control of containment water during the accidents. The formation of organic iodine in solutions used in the filtered venting system and the absorption of iodine compounds in the solutions were studied. Experiments for the formation of organic iodine on painted surfaces were also performed. (au)

Cumulative approaches to track formation under swift heavy ion (SHI) irradiation: Phenomenological correlation with formation energies of Frenkel pairs

Energy Technology Data Exchange (ETDEWEB)

Crespillo, M.L., E-mail: mcrespil@utk.edu [Centro de Microanálisis de Materiales, CMAM-UAM, Cantoblanco, Madrid 28049 (Spain); Department of Materials Science & Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Agulló-López, F., E-mail: fal@uam.es [Centro de Microanálisis de Materiales, CMAM-UAM, Cantoblanco, Madrid 28049 (Spain); Zucchiatti, A. [Centro de Microanálisis de Materiales, CMAM-UAM, Cantoblanco, Madrid 28049 (Spain)

2017-03-01

Highlights: • Extensive survey formation energies Frenkel pairs and electronic stopping thresholds. • Correlation: track formation thresholds and the energies for Frenkel pair formation. • Formation energies Frenkel pairs discussed in relation to the cumulative mechanisms. • Amorphous track formation mechanisms: defect accumulation models versus melting. • Advantages cumulative models to deal with new hot topics: nuclear-electronic synergy. - Abstract: An extensive survey for the formation energies of Frenkel pairs, as representative candidates for radiation-induced point defects, is presented and discussed in relation to the cumulative mechanisms (CM) of track formation in dielectric materials under swift heavy ion (SHI) irradiation. These mechanisms rely on the generation and accumulation of point defects during irradiation followed by collapse of the lattice once a threshold defect concentration is reached. The physical basis of those approaches has been discussed by Fecht as a defect-assisted transition to an amorphous phase. Although a first quantitative analysis of the CM model was previously performed for LiNbO{sub 3} crystals, we have, here, adopted a broader phenomenological approach. It explores the correlation between track formation thresholds and the energies for Frenkel pair formation for a broad range of materials. It is concluded that the threshold stopping powers can be roughly scaled with the energies required to generate a critical Frenkel pair concentration in the order of a few percent of the total atomic content. Finally, a comparison with the predictions of the thermal spike model is discussed within the analytical Szenes approximation.

Large Scale Generation and Characterization of Anti-Human CD34 Monoclonal Antibody in Ascetic Fluid of Balb/c Mice

Directory of Open Access Journals (Sweden)

Koushan Sineh sepehr

2013-02-01

Full Text Available Purpose: Monoclonal antibodies or specific antibodies are now an essential tool of biomedical research and are of great commercial and medical value. The purpose of this study was to produce large scale of monoclonal antibody against CD34 in order to diagnostic application in leukemia and purification of human hematopoietic stem/progenitor cells. Methods: For large scale production of monoclonal antibody, hybridoma cells that produce monoclonal antibody against human CD34 were injected into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. 5 ml ascitic fluid was harvested from each mouse in two times. Evaluation of mAb titration was assessed by ELISA method. The ascitic fluid was examined for class and subclasses by ELISA mouse mAb isotyping Kit. mAb was purified from ascitic fluid by affinity chromatography on Protein A-Sepharose. Purity of monoclonal antibody was monitored by SDS -PAGE and the purified monoclonal antibody was conjugated with FITC. Results: Monoclonal antibodies with high specificity and sensitivity against human CD34 by hybridoma technology were prepared. The subclass of antibody was IgG1 and its light chain was kappa. Conclusion: The conjugated monoclonal antibody could be a useful tool for isolation, purification and characterization of human hematopoietic stem cells.

Large Scale Generation and Characterization of Anti-Human CD34 Monoclonal Antibody in Ascetic Fluid of Balb/c Mice

Science.gov (United States)

Aghebati Maleki, Leili; Majidi, Jafar; Baradaran, Behzad; Abdolalizadeh, Jalal; Kazemi, Tohid; Aghebati Maleki, Ali; Sineh sepehr, Koushan

2013-01-01

Purpose: Monoclonal antibodies or specific antibodies are now an essential tool of biomedical research and are of great commercial and medical value. The purpose of this study was to produce large scale of monoclonal antibody against CD34 in order to diagnostic application in leukemia and purification of human hematopoietic stem/progenitor cells. Methods: For large scale production of monoclonal antibody, hybridoma cells that produce monoclonal antibody against human CD34 were injected into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. 5 ml ascitic fluid was harvested from each mouse in two times. Evaluation of mAb titration was assessed by ELISA method. The ascitic fluid was examined for class and subclasses by ELISA mouse mAb isotyping Kit. mAb was purified from ascitic fluid by affinity chromatography on Protein A-Sepharose. Purity of monoclonal antibody was monitored by SDS -PAGE and the purified monoclonal antibody was conjugated with FITC. Results: Monoclonal antibodies with high specificity and sensitivity against human CD34 by hybridoma technology were prepared. The subclass of antibody was IgG1 and its light chain was kappa. Conclusion: The conjugated monoclonal antibody could be a useful tool for isolation, purification and characterization of human hematopoietic stem cells. PMID:24312838

Generation and characterization of monoclonal antibodies against Giardia muris trophozoites.

Science.gov (United States)

Heyworth, M F; Ho, K E; Pappo, J

1989-11-01

Mouse monoclonal antibodies (mAb) were produced against Giardia muris trophozoite surface antigens. To generate B-cell hybridomas, P3/NS1/1-Ag4-1 myeloma cells were fused with splenic lymphocytes from BALB/c mice that had been immunized parenterally with G. muris trophozoites. Hybridoma culture supernatants were screened for mAb by flow cytometry of G. muris trophozoites incubated with culture supernatant followed by fluorescein-conjugated anti-mouse IgG and IgM. Flow cytometry showed three types of trophozoite staining by mAb: (i) bright staining of greater than 90% of trophozoites, with aggregation of the organisms; (ii) bright staining of approximately 90% of trophozoites, with little or no aggregation; (iii) dull staining of approximately 20% of trophozoites, without aggregation. Western blotting of mAb on G. muris trophozoite antigens separated by polyacrylamide gel electrophoresis showed that a mAb exhibiting the third of these flow cytometry staining patterns recognized trophozoite antigens of MW approximately 31,000 and 35,000. Immunoprecipitation studies indicated that the same mAb specifically precipitated two 125I-labelled trophozoite surface antigens of MW approximately 30,000. Monoclonal antibodies generated in this study may facilitate the purification and biochemical characterization of trophozoite antigens that are targets for protective intestinal antibody in G. muris-infected mice.

Detection of cyclobutane thymine dimers in DNA of human cells with monoclonal antibodies raised against a thymine dimer-containing tetranucleotide

Energy Technology Data Exchange (ETDEWEB)

Roza, L; Wulp, K.J.M. van der; MacFarlane, S J; Lohman, P H.M.; Baan, R A

1988-11-01

A hybrid cell line (hybridoma) has been isolated after fusion between mouse-plasmacytoma cells and spleen cells from mice immunized with a thymine dimer-containing tetranucleotide coupled to a carrier protein. Monoclonal antibodies produced by this hybridoma were characterized by testing the effect of various inhibitors in a competitive enzyme-linked immunosorbent assay (ELISA). The antibodies have a high specificity for thymine dimers in single-stranded DNA or poly(dT), but do not bind UV-irradiated d(TpC)/sub 5/. Less binding is observed with short thymine dimer-containing sequences. In vitro treatment of UV-irradiated DNA with photoreactivating enzyme in the presence of light, or with Micrococcus luteus UV-endonuclease results in disappearance of antigenicity. Antibody-binding to DNA isolated from UV-irradiated human fibroblasts (at 254 nm) is linear with dose. Removal of thymine dimers in these cells during a post-irradiation incubation, as detected with the antibodies, is fast initially but the rate rapidly decreases (about 50% residual dimers at 20 h after 10 J/m/sup 2/). The induction of thymine dimers in human skin irradiated with low doses of UV-B, too, was demonstrated immunochemically, by ELISA as well as by quantitative immunofluorescence microscopy.

Detection of koi herpesvirus (KHV) using a monoclonal antibody against Cyprinus carpio IgM.

Science.gov (United States)

Li, Yingying; Zheng, Shucheng; Wang, Qing; Bergmann, Sven M; Zeng, Weiwei; Wang, Yingying; Liu, Chun; Shi, Cunbin

2017-08-01

Koi herpesvirus disease (KHVD) is associated with high mortality in both common carp and koi carp (Cyprinus carpio L.) worldwide. The indirect detection of fish viruses based on the identification of antibodies has emerged as a practical and reliable means of diagnosis. Thus, it is important to create monoclonal antibodies (MAbs) against carp IgM. By using hybridoma-monoclonal antibody technology, one hybridoma cell line secreting MAbs against IgM from carp was established. In western blot analysis, the secreted MAb from cell line A5-E10 recognized the heavy chain of IgM from common carp or koi but did not react with immunoglobulins from three different fish species: grass carp (Ctenopharyngodon idella), tilapia (Oreochromis mossambicus) and Mandarin fish (Siniperca chuatsi). These results demonstrated that this MAb is highly specific for the IgM of carp and suggested that it can be used for monitoring the immunity level of carp, for example for indirect KHV diagnosis by antibody ELISA. We therefore established an indirect ELISA, which was tested using 200 serum samples from koi from three farms. The final results showed that 147 (73.5%) samples were confirmed to be KHV antibody negative and 53 (26.5%) were definitely positive, containing antibodies against KHV.

[Preparation and application of monoclonal antibodies against DR region of Na+-K+-ATPase α1 subunit].

Science.gov (United States)

Yan, Xiaofei; Wu, Litao; DU, Xiaojuan; Li, Jing; Zhang, Fujun; Han, Yan; Lyu, Shemin; Li, Dongmin

2016-12-01

Objective To prepare monoclonal antibodies against DR region (897DVEDSYGQQWTYEQR911) of Na + -K + -ATPase α1 subunit and identify their properties. Methods BALB/c mice were immunized with DR-keyholelimpet hemocyanin (KLH). Splenocytes from the immunized mice were collected and subsequently fused with SP2/0 mouse myeloma cells. Positive hybridoma clones were obtained after cell fusion and selection. ELISA was used to detect DR antibody titer in the cell supernatants. DR region-specific monoclonal antibodies were analyzed by dot blotting, Western blotting and immunofluorescence assay. Na + -K + -ATPase activity was detected by SensoLyte R FDP Protein Phosphatase Assay Kit and the protective effect of the monoclonal antibody against high glucose-induced cell injury was assessed in H9c2 cells. Results Three hybridoma cell lines which secreted stable DR monoclonal antibody were obtained. The strongest positive cell line, named DRm217, was selected to prepare ascites. Dot blotting, Western blotting and immunofluorescence assay showed that DRm217 recognized specially DR region of Na + -K + -ATPase and bound on H9c2 cell membranes. DRm217 stimulated Na + -K + -ATPase activity and alleviated high glucose-induced H9c2 cells injury. Conclusion The monoclonal antibodies against DR region of Na + -K + -ATPase α1 subunit is prepared.

Hyper-massive cloud, shock and stellar formation efficiency

International Nuclear Information System (INIS)

Louvet, Fabien

2014-01-01

O and B types stars are of paramount importance in the energy budget of galaxies and play a crucial role enriching the interstellar medium. However, their formation, unlike that of solar-type stars, is still subject to debate, if not an enigma. The earliest stages of massive star formation and the formation of their parent cloud are still crucial astrophysical questions that drew a lot of attention in the community, both from the theoretical and observational perspective, during the last decade. It has been proposed that massive stars are born in massive dense cores that form through very dynamic processes, such as converging flows of gas. During my PhD, I conducted a thorough study of the formation of dense cores and massive stars in the W43-MM1 supermassive structure, located at 6 kpc from the sun. At first, I showed a direct correlation between the star formation efficiency and the volume gas density of molecular clouds, in contrast with scenarios suggested by previous studies. Indeed, the spatial distribution and mass function of the massive dense cores currently forming in W43-MM1 suggests that this supermassive filament is undergoing a star formation burst, increasing as one approaches its center. I compared these observational results with the most recent numerical and analytical models of star formation. This comparison not only provides new constraints on the formation of supermassive filaments, but also suggests that understanding star formation in high density, extreme ridges requires a detailed portrait of the structure of these exceptional objects. Second, having shown that the formation of massive stars depends strongly on the properties of the ridges where they form, I studied the formation processes of these filaments, thanks of the characterization of their global dynamics. Specifically, I used a tracer of shocks (SiO molecule) to disentangle the feedback of local star formation processes (bipolar jets and outflows) from shocks tracing the pristine

Autonomous formation flight of helicopters: Model predictive control approach

Science.gov (United States)

Chung, Hoam

Formation flight is the primary movement technique for teams of helicopters. However, the potential for accidents is greatly increased when helicopter teams are required to fly in tight formations and under harsh conditions. This dissertation proposes that the automation of helicopter formations is a realistic solution capable of alleviating risks. Helicopter formation flight operations in battlefield situations are highly dynamic and dangerous, and, therefore, we maintain that both a high-level formation management system and a distributed coordinated control algorithm should be implemented to help ensure safe formations. The starting point for safe autonomous formation flights is to design a distributed control law attenuating external disturbances coming into a formation, so that each vehicle can safely maintain sufficient clearance between it and all other vehicles. While conventional methods are limited to homogeneous formations, our decentralized model predictive control (MPC) approach allows for heterogeneity in a formation. In order to avoid the conservative nature inherent in distributed MPC algorithms, we begin by designing a stable MPC for individual vehicles, and then introducing carefully designed inter-agent coupling terms in a performance index. Thus the proposed algorithm works in a decentralized manner, and can be applied to the problem of helicopter formations comprised of heterogenous vehicles. Individual vehicles in a team may be confronted by various emerging situations that will require the capability for in-flight reconfiguration. We propose the concept of a formation manager to manage separation, join, and synchronization of flight course changes. The formation manager accepts an operator's commands, information from neighboring vehicles, and its own vehicle states. Inside the formation manager, there are multiple modes and complex mode switchings represented as a finite state machine (FSM). Based on the current mode and collected

Heating tar sands formations to visbreaking temperatures

Science.gov (United States)

Karanikas, John Michael [Houston, TX; Colmenares, Tulio Rafael [Houston, TX; Zhang, Etuan [Houston, TX; Marino, Marian [Houston, TX; Roes, Augustinus Wilhelmus Maria [Houston, TX; Ryan, Robert Charles [Houston, TX; Beer, Gary Lee [Houston, TX; Dombrowski, Robert James [Houston, TX; Jaiswal, Namit [Houston, TX

2009-12-22

Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat may be controlled so that at least a majority of the section reaches an average temperature of between 200.degree. C. and 240.degree. C., which results in visbreaking of at least some hydrocarbons in the section. At least some visbroken hydrocarbon fluids may be produced from the formation.

Interoperability format translation and transformation between IFC architectural design file and simulation file formats

Science.gov (United States)

Chao, Tian-Jy; Kim, Younghun

2015-01-06

Automatically translating a building architecture file format (Industry Foundation Class) to a simulation file, in one aspect, may extract data and metadata used by a target simulation tool from a building architecture file. Interoperability data objects may be created and the extracted data is stored in the interoperability data objects. A model translation procedure may be prepared to identify a mapping from a Model View Definition to a translation and transformation function. The extracted data may be transformed using the data stored in the interoperability data objects, an input Model View Definition template, and the translation and transformation function to convert the extracted data to correct geometric values needed for a target simulation file format used by the target simulation tool. The simulation file in the target simulation file format may be generated.

Star formation in the multiverse

International Nuclear Information System (INIS)

Bousso, Raphael; Leichenauer, Stefan

2009-01-01

We develop a simple semianalytic model of the star formation rate as a function of time. We estimate the star formation rate for a wide range of values of the cosmological constant, spatial curvature, and primordial density contrast. Our model can predict such parameters in the multiverse, if the underlying theory landscape and the cosmological measure are known.

Mantle dynamics following supercontinent formation

Science.gov (United States)

Heron, Philip J.

This thesis presents mantle convection numerical simulations of supercontinent formation. Approximately 300 million years ago, through the large-scale subduction of oceanic sea floor, continental material amalgamated to form the supercontinent Pangea. For 100 million years after its formation, Pangea remained relatively stationary, and subduction of oceanic material featured on its margins. The present-day location of the continents is due to the rifting apart of Pangea, with supercontinent dispersal being characterized by increased volcanic activity linked to the generation of deep mantle plumes. The work presented here investigates the thermal evolution of mantle dynamics (e.g., mantle temperatures and sub-continental plumes) following the formation of a supercontinent. Specifically, continental insulation and continental margin subduction are analyzed. Continental material, as compared to oceanic material, inhibits heat flow from the mantle. Previous numerical simulations have shown that the formation of a stationary supercontinent would elevate sub-continental mantle temperatures due to the effect of continental insulation, leading to the break-up of the continent. By modelling a vigorously convecting mantle that features thermally and mechanically distinct continental and oceanic plates, this study shows the effect of continental insulation on the mantle to be minimal. However, the formation of a supercontinent results in sub-continental plume formation due to the re-positioning of subduction zones to the margins of the continent. Accordingly, it is demonstrated that continental insulation is not a significant factor in producing sub-supercontinent plumes but that subduction patterns control the location and timing of upwelling formation. A theme throughout the thesis is an inquiry into why geodynamic studies would produce different results. Mantle viscosity, Rayleigh number, continental size, continental insulation, and oceanic plate boundary evolution are

The three phases of galaxy formation

Science.gov (United States)

Clauwens, Bart; Schaye, Joop; Franx, Marijn; Bower, Richard G.

2018-05-01

We investigate the origin of the Hubble sequence by analysing the evolution of the kinematic morphologies of central galaxies in the EAGLE cosmological simulation. By separating each galaxy into disc and spheroidal stellar components and tracing their evolution along the merger tree, we find that the morphology of galaxies follows a common evolutionary trend. We distinguish three phases of galaxy formation. These phases are determined primarily by mass, rather than redshift. For M* ≲ 109.5M⊙ galaxies grow in a disorganised way, resulting in a morphology that is dominated by random stellar motions. This phase is dominated by in-situ star formation, partly triggered by mergers. In the mass range 109.5M⊙ ≲ M* ≲ 1010.5M⊙ galaxies evolve towards a disc-dominated morphology, driven by in-situ star formation. The central spheroid (i.e. the bulge) at z = 0 consists mostly of stars that formed in-situ, yet the formation of the bulge is to a large degree associated with mergers. Finally, at M* ≳ 1010.5M⊙ growth through in-situ star formation slows down considerably and galaxies transform towards a more spheroidal morphology. This transformation is driven more by the buildup of spheroids than by the destruction of discs. Spheroid formation in these galaxies happens mostly by accretion at large radii of stars formed ex-situ (i.e. the halo rather than the bulge).

Hard sludge formation in modern steam generators of nuclear power plants. Formation, risks and mitigation

International Nuclear Information System (INIS)

Strohmer, F.

2014-01-01

In recent years modern steam generators with triangular pitch tube bundle geometry have experienced damage caused by hard sludge formation on top of the tube sheet and denting. The effect can lead to a limitation of the modern steam generators’ lifetime. The current publication shows reasons for the generation of hard sludge formation. Moreover, it describes the risk arising from hard sludge formation for the concerned steam generators and the mitigation of the problem. The main factors contributing to the formation of hard sludge are: the amount of corrosion product ingress into the steam generators, hard sludge formation favouring impurities and, skipped maintenance applications during outages. The main damaging mechanism of denting that can arise under certain secondary side conditions from hard sludge is explained. For steam generator tube denting, aggressive, oxidizing conditions have to be established in crevices beneath the hard sludge piles. Severely dented tubes are sensitive toward outer diameter stress corrosion cracking (ODSCC). The denting and ODSCC mechanism is explained. In addition, a proactive long-term maintenance strategy to avoid the formation of hard sludge piles will be shown. The strategy is based on a reduction of the corrosion product ingress into the steam generator's secondary side, and on the regular removal of deposits from the tube sheet and from the entire upper bundle area by latest mechanical cleaning methods. For hard deposits - formed either by silicates or long term hardened corrosion products, which, in the past, could not be removed by chemical or mechanical means - a new, simple, mechanical cleaning method is presented. This method can be used during the normal time frame of an outage and allows the restart of the unit with clean steam generator tube sheets. This mitigates the tendency to form hard sludge and denting in the long term. (author)

Muonium/muonic hydrogen formation in atomic hydrogen

Indian Academy of Sciences (India)

The muonium/muonic hydrogen atom formation in ± –H collisions is investigated, using a two-state approximation in a time dependent formalism. It is found that muonium cross-section results are similar to the cross-section results obtained for positronium formation in + –H collision. Muonic hydrogen atom formation ...

Formative assessment: a student perspective.

Science.gov (United States)

Hill, D A; Guinea, A I; McCarthy, W H

1994-09-01

An educator's view would be that formative assessment has an important role in the learning process. This study was carried out to obtain a student perspective of the place of formative assessment in the curriculum. Final-year medical students at Royal Prince Alfred Hospital took part in four teaching sessions, each structured to integrate teaching with assessment. Three assessment methods were used; the group objective structured clinical examination (G-OSCE), structured short answer (SSA) questions and a pre/post-test multiple choice questionnaire (MCQ). Teaching sessions were conducted on the subject areas of traumatology, the 'acute abdomen', arterial disorders and cancer. Fifty-five students, representing 83% of those who took part in the programme, responded to a questionnaire where they were asked to rate (on a 5-point Likert scale) their response to general questions about formative assessment and 13 specific questions concerning the comparative value of the three assessment modalities. Eighty-nine per cent of respondents felt that formative assessment should be incorporated into the teaching process. The SSA assessment was regarded as the preferred modality to reinforce previous teaching and test problem-solving skills. The MCQ was the least favoured assessment method. The effect size variable between the total scores for the SSA and MCQ was 0.64. The variable between G-OSCE and SSA/MCQ was 0.26 and 0.33 respectively. Formative assessment is a potentially powerful method to direct learning behaviour. Students should have input into the methods used.

Secretory processes involved in the formation of milk

International Nuclear Information System (INIS)

Knutsson, P.G.

1976-01-01

Current knowledge on milk formation is reviewed. Emphasis is given to sites of formation of protein, fat and lactose, and transfer of these compounds into the alveolar lumen. Further, the formation of the water phase of milk is thoroughly discussed, and evidence presented that milk formation includes both secretory and re-absorptive processes as well as diffusion. A short presentation of colostrum formation is included. Neither biochemical processes involved in synthesis of organic compounds nor mammary gland endocrinology are discussed. (author)

Increased formate overflow is a hallmark of oxidative cancer.

Science.gov (United States)

Meiser, Johannes; Schuster, Anne; Pietzke, Matthias; Vande Voorde, Johan; Athineos, Dimitris; Oizel, Kristell; Burgos-Barragan, Guillermo; Wit, Niek; Dhayade, Sandeep; Morton, Jennifer P; Dornier, Emmanuel; Sumpton, David; Mackay, Gillian M; Blyth, Karen; Patel, Ketan J; Niclou, Simone P; Vazquez, Alexei

2018-04-10

Formate overflow coupled to mitochondrial oxidative metabolism\\ has been observed in cancer cell lines, but whether that takes place in the tumor microenvironment is not known. Here we report the observation of serine catabolism to formate in normal murine tissues, with a relative rate correlating with serine levels and the tissue oxidative state. Yet, serine catabolism to formate is increased in the transformed tissue of in vivo models of intestinal adenomas and mammary carcinomas. The increased serine catabolism to formate is associated with increased serum formate levels. Finally, we show that inhibition of formate production by genetic interference reduces cancer cell invasion and this phenotype can be rescued by exogenous formate. We conclude that increased formate overflow is a hallmark of oxidative cancers and that high formate levels promote invasion via a yet unknown mechanism.

String Formatting Considered Harmful for Novice Programmers

Science.gov (United States)

Hughes, Michael C.; Jadud, Matthew C.; Rodrigo, Ma. Mercedes T.

2010-01-01

In Java, "System.out.printf" and "String.format" consume a specialised kind of string commonly known as a format string. In our study of first-year students at the Ateneo de Manila University, we discovered that format strings present a substantial challenge for novice programmers. Focusing on their first laboratory we found…

Planet Formation

Science.gov (United States)

Podolak, Morris

2018-04-01

Modern observational techniques are still not powerful enough to directly view planet formation, and so it is necessary to rely on theory. However, observations do give two important clues to the formation process. The first is that the most primitive form of material in interstellar space exists as a dilute gas. Some of this gas is unstable against gravitational collapse, and begins to contract. Because the angular momentum of the gas is not zero, it contracts along the spin axis, but remains extended in the plane perpendicular to that axis, so that a disk is formed. Viscous processes in the disk carry most of the mass into the center where a star eventually forms. In the process, almost as a by-product, a planetary system is formed as well. The second clue is the time required. Young stars are indeed observed to have gas disks, composed mostly of hydrogen and helium, surrounding them, and observations tell us that these disks dissipate after about 5 to 10 million years. If planets like Jupiter and Saturn, which are very rich in hydrogen and helium, are to form in such a disk, they must accrete their gas within 5 million years of the time of the formation of the disk. Any formation scenario one proposes must produce Jupiter in that time, although the terrestrial planets, which don't contain significant amounts of hydrogen and helium, could have taken longer to build. Modern estimates for the formation time of the Earth are of the order of 100 million years. To date there are two main candidate theories for producing Jupiter-like planets. The core accretion (CA) scenario supposes that any solid materials in the disk slowly coagulate into protoplanetary cores with progressively larger masses. If the core remains small enough it won't have a strong enough gravitational force to attract gas from the surrounding disk, and the result will be a terrestrial planet. If the core grows large enough (of the order of ten Earth masses), and the disk has not yet dissipated, then

Exploring the value of usability feedback formats

DEFF Research Database (Denmark)

Nørgaard, Mie; Hornbæk, Kasper Anders Søren

2009-01-01

The format used to present feedback from usability evaluations to developers affects whether problems are understood, accepted, and fixed. Yet, little research has investigated which formats are the most effective. We describe an explorative study where three developers assess 40 usability findings...... presented using five feedback formats. Our usability findings comprise 35 problems and 5 positive comments. Data suggest that feedback serves multiple purposes. Initially, feedback must convince developers about the relevance of a problem and convey an understanding of this. Feedback must next be easy...... working with the feedback to address the usability problems, there were no significant differences among the developers' ratings of the value of the different formats. This suggests that all of the formats may serve equally well as reminders in later stages of working with usability problems...

The role of the family in personality formation

Directory of Open Access Journals (Sweden)

Pylkov E.A.

2018-04-01

Full Text Available the article reveals such actual components of modern society as family, personality formation in the family, formation of the self-concept, life-purpose orientations of modern youth. One of the key moments in personality formation is movement, action. Formation involves personality development, both physically and spiritually from the very beginning of a person's life.

Academic Formation and Formative Research Integration Management for the Culmination of Studies Process in Higher Education

Directory of Open Access Journals (Sweden)

Lorna Cruz Rizo

2016-12-01

Full Text Available Given the up- dated international difficulties in the completion of studies process, theoretical and practical studies developed in this field are surprisingly scarce. Particularly, there has been a limited quantity of students that support their diploma thesis after completing their credits at the School of Languages and Linguistics at the University of Guayaquil. Consequently, this paper faces the problem of the insufficiencies in the culmination of studies process in relation to the management of the academic and scientific formation. Thus, the objective is: to improve the completion of studies or degree- obtaining processes in university education, through the implementation of a praxiological proposal of academic formation and formative research integration. Accordingly, the author´s experiences systematization is the methodology mainly used. The essential logic for the management of the academic formation and formative research integration was revealed as the main proposal, therefore this is the solution to the problem diagnosed. This is based on a curricular structure, in which each of the subjects was interrelated to each of the essential stages of the scientific research. As main results obtained, the students were able to solve real-life problems diagnosed at educative institutions, also they drew up the draft of their theses.

Planetesimal formation starts at the snow line

Science.gov (United States)

Drążkowska, J.; Alibert, Y.

2017-12-01

Context. The formation stage of planetesimals represents a major gap in our understanding of the planet formation process. Late-stage planet accretion models typically make arbitrary assumptions about planetesimal and pebble distribution, while dust evolution models predict that planetesimal formation is only possible at some orbital distances. Aims: We wish to test the importance of the water snow line in triggering the formation of the first planetesimals during the gas-rich phase of a protoplanetary disk, when cores of giant planets have to form. Methods: We connected prescriptions for gas disk evolution, dust growth and fragmentation, water ice evaporation and recondensation, the transport of both solids and water vapor, and planetesimal formation via streaming instability into a single one-dimensional model for protoplanetary disk evolution. Results: We find that processes taking place around the snow line facilitate planetesimal formation in two ways. First, because the sticking properties between wet and dry aggregates change, a "traffic jam" inside of the snow line slows the fall of solids onto the star. Second, ice evaporation and outward diffusion of water followed by its recondensation increases the abundance of icy pebbles that trigger planetesimal formation via streaming instability just outside of the snow line. Conclusions: Planetesimal formation is hindered by growth barriers and radial drift and thus requires particular conditions to take place. The snow line is a favorable location where planetesimal formation is possible for a wide range of conditions, but not in every protoplanetary disk model, however. This process is particularly promoted in large cool disks with low intrinsic turbulence and an increased initial dust-to-gas ratio. The movie attached to Fig. 3 is only available at http://www.aanda.org

Development of a Recombinant Antibody with Specificity for Chelated Uranyl Ions

International Nuclear Information System (INIS)

X. Li; A.M. Kriegel; T.C. Bishop; R.C. Blake; E. Figueiredo; H. Yu; D.A. Blake

2005-01-01

The goal of our project is to continue the development of new techniques for rapid, automated identification of radionuclides, metals, and chelators that may contaminant sur face and groundwater at DOE sites. One of the four specific aims of the present project is to develop new technologies in antibody engineering that will enhance our immunosensor program. Recombinant antibodies have potential advantages over monoclonal antibodies produced by standard hybridoma technology. The cloned genes represent a stable, recoverable source for antibody production. In addition, the recombinant format offers opportunities for protein engineering that enhances antibody performance and for studies that relate antibody sequence to binding activity. In this study, a hybridoma that synthesized an antibody (12F6) that recognized a 1:1 complex between 2,9-dicarboxyl-1,10- phenanthroline (DCP) and UO 2 2+ was used as a source of RNA for the development of a recombinant (Fab) 2 fragment. RNA was isolated from the 12F6 hybridoma and the cDNA encoding the entire κ light chain and the linked VH and C1 portions of the heavy chain were amplified from total RNA. cDNA sequences were verified by comparison with the N-terminal amino acid sequences of the light and heavy chains of the native 12F6 monoclonal antibody. A leader sequence and appropriate restriction sites were added to each chain, and the fragments were ligated into a commercial dicistronic vector (pBudCE4.1, Invitrogen, Inc.). COS-1 cells were transfected with this vector and the culture supernatant was assayed for activity and the (Fab) 2 protein. Cells transfected with vector containing 12F6 cDNA synthesized and secreted recombinant (Fab) 2 fragments that bound to the UO 2 2+ -DCP complex with an affinity indistinguishable from that of a (Fab) 2 fragment prepared from the native antibody. Molecular models of the heavy and light chain variable domains were constructed according to the canonical structures method detailed by Morea

Terrestrial planet formation.

Science.gov (United States)

Righter, K; O'Brien, D P

2011-11-29

Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (~10(6) y), followed by planetesimals to embryos (lunar to Mars-sized objects; few 10(6) y), and finally embryos to planets (10(7)-10(8) y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids.

Star formation in active galaxies and quasars

International Nuclear Information System (INIS)

Heckman, T.M.

1987-01-01

I review the observational evidence for a causal or statistical link between star formation and active galactic nuclei. The chief difficulty is in quantitatively ascertaining the star formation rate in active galaxies: most of the readily observable manifestations of star formation superficially resemble those of an active nucleus. Careful multi-wavelength spatially-resolved observations demonstrate that many Seyfert galaxies are undergoing star formation. Our survey of CO emission from Seyferts (interpreted in conjunction IRAS data) suggests that type 2 Seyferts have unusually high rates of star formation, but type 1 Seyferts do not. Recent work also suggests that many powerful radio galaxies may be actively forming stars: radio galaxies with strong emission-lines often have blue colors and strong far-infrared emission. Determining the star formation rate in the host galaxies of quasars is especially difficult. Multi-color imaging and long-slit spectroscopy suggests that many of the host galaxies of radio-loud quasars are blue and a cold interstellar medium has been detected in some quasar hosts

Networks for Autonomous Formation Flying Satellite Systems

Science.gov (United States)

Knoblock, Eric J.; Konangi, Vijay K.; Wallett, Thomas M.; Bhasin, Kul B.

2001-01-01

The performance of three communications networks to support autonomous multi-spacecraft formation flying systems is presented. All systems are comprised of a ten-satellite formation arranged in a star topology, with one of the satellites designated as the central or "mother ship." All data is routed through the mother ship to the terrestrial network. The first system uses a TCP/lP over ATM protocol architecture within the formation the second system uses the IEEE 802.11 protocol architecture within the formation and the last system uses both of the previous architectures with a constellation of geosynchronous satellites serving as an intermediate point-of-contact between the formation and the terrestrial network. The simulations consist of file transfers using either the File Transfer Protocol (FTP) or the Simple Automatic File Exchange (SAFE) Protocol. The results compare the IF queuing delay, and IP processing delay at the mother ship as well as application-level round-trip time for both systems, In all cases, using IEEE 802.11 within the formation yields less delay. Also, the throughput exhibited by SAFE is better than FTP.

Large Scale Generation and Characterization of Anti-Human IgA Monoclonal Antibody in Ascitic Fluid of Balb/c Mice

OpenAIRE

Fatemeh Ezzatifar; Jafar Majidi; Behzad Baradaran; Leili Aghebati Maleki; Jalal Abdolalizadeh; Mehdi Yousefi

2015-01-01

Purpose: Monoclonal antibodies are potentially powerful tools used in biomedical research, diagnosis, and treatment of infectious diseases and cancers. The monoclonal antibody against Human IgA can be used as a diagnostic application to detect infectious diseases. The aim of this study was to improve an appropriate protocol for large-scale production of mAbs against IgA. Methods: For large-scale production of the monoclonal antibody, hybridoma cells that produce monoclonal antibodies again...

Large Scale Generation and Characterization of Anti-Human CD34 Monoclonal Antibody in Ascetic Fluid of Balb/c Mice

OpenAIRE

Aghebati Maleki, Leili; Majidi, Jafar; Baradaran, Behzad; Abdolalizadeh, Jalal; Kazemi, Tohid; Aghebati Maleki, Ali; Sineh sepehr, Koushan

2013-01-01

Purpose: Monoclonal antibodies or specific antibodies are now an essential tool of biomedical research and are of great commercial and medical value. The purpose of this study was to produce large scale of monoclonal antibody against CD34 in order to diagnostic application in leukemia and purification of human hematopoietic stem/progenitor cells. Methods: For large scale production of monoclonal antibody, hybridoma cells that produce monoclonal antibody against human CD34 were injected into t...

Monoclonal anti-human factor VII antibodies. Detection in plasma of a second protein antigenically and genetically related to factor VII.

OpenAIRE

Broze, G J; Hickman, S; Miletich, J P

1985-01-01

Several murine monoclonal anti-human Factor VII antibodies were produced using hybridoma technology. Two noncompetitive monoclonal antibodies were used to examine by Western blotting the Factor VII cross-reactive material (CRM) in normal human plasma and three commercially available congenitally Factor VII-deficient plasmas, and to construct a facile "sandwich" immunoassay for plasma Factor VII. A second, previously undescribed, form of Factor VII CRM was detected in human plasma, which on We...

Radiation pressure in super star cluster formation

Science.gov (United States)

Tsang, Benny T.-H.; Milosavljević, Miloš

2018-05-01

The physics of star formation at its extreme, in the nuclei of the densest and the most massive star clusters in the universe—potential massive black hole nurseries—has for decades eluded scrutiny. Spectroscopy of these systems has been scarce, whereas theoretical arguments suggest that radiation pressure on dust grains somehow inhibits star formation. Here, we harness an accelerated Monte Carlo radiation transport scheme to report a radiation hydrodynamical simulation of super star cluster formation in turbulent clouds. We find that radiation pressure reduces the global star formation efficiency by 30-35%, and the star formation rate by 15-50%, both relative to a radiation-free control run. Overall, radiation pressure does not terminate the gas supply for star formation and the final stellar mass of the most massive cluster is ˜1.3 × 106 M⊙. The limited impact as compared to in idealized theoretical models is attributed to a radiation-matter anti-correlation in the supersonically turbulent, gravitationally collapsing medium. In isolated regions outside massive clusters, where the gas distribution is less disturbed, radiation pressure is more effective in limiting star formation. The resulting stellar density at the cluster core is ≥108 M⊙ pc-3, with stellar velocity dispersion ≳ 70 km s-1. We conclude that the super star cluster nucleus is propitious to the formation of very massive stars via dynamical core collapse and stellar merging. We speculate that the very massive star may avoid the claimed catastrophic mass loss by continuing to accrete dense gas condensing from a gravitationally-confined ionized phase.

JOYFOR: A program for transformation of NJOY results in MATXS-format to the MITRA input format

International Nuclear Information System (INIS)

Krieg, B.; Broeders, I.

1987-02-01

The program JOYFOR is the connection between the output of the group constant calculation code NJOY in MATXS-format and the testing and formatting program MITRA. Resonance selfshielding factors as well as transfermatrices for elastic and inelastic scattering and for (n,2n)- and (n,3n)-processes, normalized corresponding to the conventions of MITRA, are calculated by JOYFOR from the NJOY results and are written in MIGROS-format on an external file and on the standard output unit. Also the group cross-sections for infinite dilution, the 1/v-values and the fission spectrum are written out in the same format as in MIGROS. KERMA-factors are handled by JOYFOR in the same way as group cross-sections. The output data of JOYFOR may be tested by MITRA and transformed into input for the GRUBA management program GRUMA. The present version of JOYFOR handles group constants for neutron reactions only. Extension of the program to photon reactions is being planned. (orig.) [de

Crenarchaeal biofilm formation under extreme conditions.

Directory of Open Access Journals (Sweden)

Andrea Koerdt

Full Text Available BACKGROUND: Biofilm formation has been studied in much detail for a variety of bacterial species, as it plays a major role in the pathogenicity of bacteria. However, only limited information is available for the development of archaeal communities that are frequently found in many natural environments. METHODOLOGY: We have analyzed biofilm formation in three closely related hyperthermophilic crenarchaeotes: Sulfolobus acidocaldarius, S. solfataricus and S. tokodaii. We established a microtitre plate assay adapted to high temperatures to determine how pH and temperature influence biofilm formation in these organisms. Biofilm analysis by confocal laser scanning microscopy demonstrated that the three strains form very different communities ranging from simple carpet-like structures in S. solfataricus to high density tower-like structures in S. acidocaldarius in static systems. Lectin staining indicated that all three strains produced extracellular polysaccharides containing glucose, galactose, mannose and N-acetylglucosamine once biofilm formation was initiated. While flagella mutants had no phenotype in two days old static biofilms of S. solfataricus, a UV-induced pili deletion mutant showed decreased attachment of cells. CONCLUSION: The study gives first insights into formation and development of crenarchaeal biofilms in extreme environments.

Fusomorphogenesis: cell fusion in organ formation.

Science.gov (United States)

Shemer, G; Podbilewicz, B

2000-05-01

Cell fusion is a universal process that occurs during fertilization and in the formation of organs such as muscles, placenta, and bones. Very little is known about the molecular and cellular mechanisms of cell fusion during pattern formation. Here we review the dynamic anatomy of all cell fusions during embryonic and postembryonic development in an organism. Nearly all the cell fates and cell lineages are invariant in the nematode C. elegans and one third of the cells that are born fuse to form 44 syncytia in a reproducible and stereotyped way. To explain the function of cell fusion in organ formation we propose the fusomorphogenetic model as a simple cellular mechanism to efficiently redistribute membranes using a combination of cell fusion and polarized membrane recycling during morphogenesis. Thus, regulated intercellular and intracellular membrane fusion processes may drive elongation of the embryo as well as postembryonic organ formation in C. elegans. Finally, we use the fusomorphogenetic hypothesis to explain the role of cell fusion in the formation of organs like muscles, bones, and placenta in mammals and other species and to speculate on how the intracellular machinery that drive fusomorphogenesis may have evolved.

Transient Exciplex Formation Electron Transfer Mechanism

Directory of Open Access Journals (Sweden)

Michael G. Kuzmin

2011-01-01

Full Text Available Transient exciplex formation mechanism of excited-state electron transfer reactions is analyzed in terms of experimental data on thermodynamics and kinetics of exciplex formation and decay. Experimental profiles of free energy, enthalpy, and entropy for transient exciplex formation and decay are considered for several electron transfer reactions in various solvents. Strong electronic coupling in contact pairs of reactants causes substantial decrease of activation energy relative to that for conventional long-range ET mechanism, especially for endergonic reactions, and provides the possibility for medium reorganization concatenated to gradual charge shift in contrast to conventional preliminary medium and reactants reorganization. Experimental criteria for transient exciplex formation (concatenated mechanism of excited-state electron transfer are considered. Available experimental data show that this mechanism dominates for endergonic ET reactions and provides a natural explanation for a lot of known paradoxes of ET reactions.

Marker of cemento-periodontal ligament junction associated with periodontal regeneration.

Science.gov (United States)

Hara, Ryohko; Wato, Masahiro; Tanaka, Akio

2005-06-01

The purpose of this study was to identify factors promoting formation of the cemento-periodontal ligament junction. Regeneration of the cemento-periodontal ligament junction is an important factor in recovery of the connective tissue attachment to the cementum and it is important to identify all specific substances that promote its formation. To clarify the substances involved in cemento-periodontal ligament junction formation, we produced a monoclonal antibody (mAb) to human cemento-periodontal ligament junction (designated as the anti-TAP mAb) and examined its immunostaining properties and reactive antigen. Hybridomas producing monoclonal antibody against human cemento-periodontal ligament junction antigens were established by fusing P3U1 mouse myeloma cells with spleen cells from BALB/c mice immunized with homogenized human cemento-periodontal ligament junction. The mAb, the anti-TAP mAb for cemento-periodontal ligament junction, was then isolated. The immunoglobulin class and light chain of the mAb were examined using an isotyping kit. Before immunostaining, antigen determination using an enzymatic method or heating was conducted. Human teeth, hard tissue-forming lesions, and animal tissues were immunostained by the anti-TAP mAb. The anti-TAP mAb was positive in human cemento-periodontal ligament junction and predentin but negative in all other human and animal tissues examined. In the cemento-osseous lesions, the anti-TAP mAb was positive in the peripheral area of the cementum and cementum-like hard tissues and not in the bone and bone-like tissues. The anti-TAP mAb showed IgM (kappa) and recognized phosphoprotein. The anti-TAP mAb is potentially useful for developing new agents promoting cementogenesis and periodontal regeneration.

Towards the Rosetta Stone of planet formation

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Schmidt T.O.B.

2011-02-01

Full Text Available Transiting exoplanets (TEPs observed just ~10 Myrs after formation of their host systems may serve as the Rosetta Stone for planet formation theories. They would give strong constraints on several aspects of planet formation, e.g. time-scales (planet formation would then be possible within 10 Myrs, the radius of the planet could indicate whether planets form by gravitational collapse (being larger when young or accretion growth (being smaller when young. We present a survey, the main goal of which is to find and then characterise TEPs in very young open clusters.

Review of nutrition labeling formats.

Science.gov (United States)

Geiger, C J; Wyse, B W; Parent, C R; Hansen, R G

1991-07-01

This article examines nutrition labeling history as well as the findings of nine research studies of nutrition labeling formats. Nutrition labeling regulations were announced in 1973 and have been periodically amended since then. In response to requests from consumers and health care professionals for revision of the labeling system, the Food and Drug Administration initiated a three-phase plan for reform of nutrition labeling in 1990. President Bush signed the Nutrition Labeling and Education Act in November 1990. Literature analysis revealed that only nine studies with an experimental design have focused on nutrition labeling since 1971. Four were conducted before 1975, which was the year that nutrition labeling was officially implemented, two were conducted in 1980, and three were conducted after 1986. Only two of the nine studies supported the traditional label format mandated by the Code of Federal Regulations, and one study partially supported it. Four of the nine studies that evaluated graphic presentations of nutrition information found that consumer comprehension of nutrition information was improved with a graphic format for nutrition labeling: three studies supported the use of bar graphs and one study supported the use of a pie chart. Full disclosure (ie, complete nutrient and ingredient labeling) was preferred by consumers in two of the three studies that examined this variable. The third study supported three types of information disclosure dependent upon socioeconomic class. In those studies that tested graphics, a bar graph format was significantly preferred and showed better consumer comprehension than the traditional format.

Chain formation of metal atoms

DEFF Research Database (Denmark)

Bahn, Sune Rastad; Jacobsen, Karsten Wedel

2001-01-01

The possibility of formation of single-atomic chains by manipulation of nanocontacts is studied for a selection of metals (Ni, Pd, Pt, Cu, Ag, Au). Molecular dynamics simulations show that the tendency for chain formation is strongest for Au and Pt. Density functional theory calculations indicate...... that the metals which form chains exhibit pronounced many-atom interactions with strong bonding in low coordinated systems....

Influence of fluorosurfactants on hydrate formation rates

Energy Technology Data Exchange (ETDEWEB)

Kim, C.U.; Jeong, K.E.; Chae, H.J.; Jeong, S.Y. [Korea Reasearch Inst. of Chemical Technology, Alternative Chemicals/Fuel Research Center, Yuseong-Gu, Daejon (Korea, Republic of)

2008-07-01

Gas hydrates, or clathrates, are ice-like solids that forms when natural gas is in contact with liquid water or ice under high pressure and low temperature. There is significant interest in studying the storage and transportation of gas in the form of hydrates. However, a critical problem impacting the industrial application of gas hydrates for storage and transportation of natural gas is the slow formation rate of natural gas hydrate. Researchers have previously reported on the promotion effect of some additives on gas hydrate formation and hydrate gas content. Fluorosurfactants are significantly superior to nonfluorinated surfactants in wetting action, as well as stability in harsh environments, both thermal and chemical. This paper discussed an experimental investigation into the effects of fluorosurfactants with different ionic types on the formation of methane hydrate. The surfactants used were FSN-100 of DuPont Zonyl as non-ionic surfactant and FC-143 of DuPont as anionic surfactant. The paper discussed the experimental apparatus for methane hydrate formation. It also discussed hydrate formation kinetics and the series of hydrate formation experiments that were conducted in the presence of fluorosurfactants. Last, the paper explored the results of the study. It was concluded that anionic fluorosurfactant of FC-143 had a better promoting effect on methane hydrate formation compared with nonionic surfactant of FSN-100. 8 refs., 2 tabs., 2 figs.

Distributed formation control for autonomous robots

NARCIS (Netherlands)

Garcia de Marina Peinado, Hector Jesús

2016-01-01

This thesis addresses several theoretical and practical problems related to formation-control of autonomous robots. Formation-control aims to simultaneously accomplish the tasks of forming a desired shape by the robots and controlling their coordinated collective motion. This kind of robot

Computer-based feedback in formative assessment

NARCIS (Netherlands)

van der Kleij, Fabienne

2013-01-01

Formative assessment concerns any assessment that provides feedback that is intended to support learning and can be used by teachers and/or students. Computers could offer a solution to overcoming obstacles encountered in implementing formative assessment. For example, computer-based assessments

The formation of stars

CERN Document Server

Stahler, Steven W

2008-01-01

This book is a comprehensive treatment of star formation, one of the most active fields of modern astronomy. The reader is guided through the subject in a logically compelling manner. Starting from a general description of stars and interstellar clouds, the authors delineate the earliest phases of stellar evolution. They discuss formation activity not only in the Milky Way, but also in other galaxies, both now and in the remote past. Theory and observation are thoroughly integrated, with the aid of numerous figures and images. In summary, this volume is an invaluable resource, both as a text f

Results of a downhole formation microscanner study in a Juro-Triassic-aged sedimentary deposit (Passaic Formation)

International Nuclear Information System (INIS)

Fischer, J.A.; Fischer, J.J.; Bullwinkel, R.J.

1994-01-01

Studies to determine the structural and geohydrological properties of the Passaic Formation were performed at two sites. Both sites are located in northeastern New Jersey, within the Juro-Triassic-aged Newark Basin. The Passaic Formation rocks are described in the literature as a reddish brown, thin to massively bedded, sedimentary deposit with lithology ranging from claystone through conglomerate. A fractured open-quotes layer cakeclose quotes model has been proposed (and is generally accepted) to describe the prevailing geohydrological conditions. The Formation MicroScanner tool was used in four wells drilled for these projects (two at each site). In addition to this microresistivity tool, a suite of other oil field geophysical tools (Gamma, Induction, Dipmeter, Temperature, and Neutron probes) were also utilized. The data collected with the Formation MicroScanner were correlated with detailed logs and the continuous core retrieved from three of the wells. Pump test data was also obtained at both sites. The geophysical data obtained at both sites allowed the direct identification of fractures and their orientation in relation to bedding. Fracture and bedding aperture size and orientation were measured. The results, as presented in this paper, show a high degree of inhomogeneity at both sites rather than the conventional layer cake model. For appropriate site analyses it was necessary to significantly refine the previously assumed Passaic Formation geohydrological and structural model. 14 refs., 4 figs

Biostratigraphy of the Gurpi Formation in Zagros Basin, Iran

Directory of Open Access Journals (Sweden)

2015-10-01

Full Text Available Introdaction   The Gurpi Formation is developed in the central of the Zagros fold in Khuzestan, Lorestan and Fars provinces of southwestern Iran, defined az theZagros basin ,The Gurpi refers to Gurpi Mountain in the Kuzestan province.type section gurpi,which is N of the Lali oil wells and N-E of Masjed – Soleiman city,comprises 320m argillaceous limestone and gry-to-blueshale marl(James and Wynd,1965Although the boundary the Gurpi Formation and the underlying Ilam Formation is reported to be gradual,the altered facies found at this boundrary could be a sign of a low disconformity or even unconformity.In some place,the Ilam Formation does not exist and tne Gurpi Formation lie abave the Sarvak Formation.The upper boundry of the Gurpi Formation is more noticeable and there are different overlying formations.In Khozstan province,the Gurpi Formation is overlain by purplr shale of pabdeh Formation with signs of unconformity.The Gurpi Formation is not always concurrent. Biostratigraphy and lithological characteries of the Gurpi Formation were studied by James and Wynd (1965, Taheri (1998, KameliAzao (2002, Zarei (2005, Hematinasab (2008, Madavian (2009, Tavalaian (2011. This research study aims at describing the biostratigraphy of Gurpi Formation.In this study five stratigraphic section is investigate for its Planktonc Foraminiforal content.     Method and Matrials   This study involves five stratigraphic sections from the Gurpi Formation that were measured the ticknes and determind of Litostratigrapic limit as well as recognizd of detail litostrstigray the Gurpi Formation.More than 525 thine sections were examined. Some samples from the underlying Pabdeh Formation were also analysed for comparison. then recognizd Genus and species of Planktonic foraminifera and biozones mentioned wells have been introduced. In order to the biozonation of Gurpi Formation, stratigraphic distribution of well- known foraminifora is recognizd and then biozones are

Biostratigraphy of the Gurpi Formation in Zagros Basin, Iran

Directory of Open Access Journals (Sweden)

Abbas Sadeghi

2015-09-01

Full Text Available   Introdaction   The Gurpi Formation is developed in the central of the Zagros fold in Khuzestan, Lorestan and Fars provinces of southwestern Iran, defined az theZagros basin ,The Gurpi refers to Gurpi Mountain in the Kuzestan province.type section gurpi,which is N of the Lali oil wells and N-E of Masjed – Soleiman city,comprises 320m argillaceous limestone and gry-to-blueshale marl(James and Wynd,1965Although the boundary the Gurpi Formation and the underlying Ilam Formation is reported to be gradual,the altered facies found at this boundrary could be a sign of a low disconformity or even unconformity.In some place,the Ilam Formation does not exist and tne Gurpi Formation lie abave the Sarvak Formation.The upper boundry of the Gurpi Formation is more noticeable and there are different overlying formations.In Khozstan province,the Gurpi Formation is overlain by purplr shale of pabdeh Formation with signs of unconformity.The Gurpi Formation is not always concurrent. Biostratigraphy and lithological characteries of the Gurpi Formation were studied by James and Wynd (1965, Taheri (1998, KameliAzao (2002, Zarei (2005, Hematinasab (2008, Madavian (2009, Tavalaian (2011. This research study aims at describing the biostratigraphy of Gurpi Formation.In this study five stratigraphic section is investigate for its Planktonc Foraminiforal content.     Method and Matrials   This study involves five stratigraphic sections from the Gurpi Formation that were measured the ticknes and determind of Litostratigrapic limit as well as recognizd of detail litostrstigray the Gurpi Formation.More than 525 thine sections were examined. Some samples from the underlying Pabdeh Formation were also analysed for comparison. then recognizd Genus and species of Planktonic foraminifera and biozones mentioned wells have been introduced. In order to the biozonation of Gurpi Formation, stratigraphic distribution of well- known foraminifora is recognizd and

Right timing in formative program evaluation.

Science.gov (United States)

Hall, Jori; Freeman, Melissa; Roulston, Kathy

2014-08-01

Since many educational researchers and program developers have limited knowledge of formative evaluation, formative data may be underutilized during the development and implementation of an educational program. The purpose of this article is to explain how participatory, responsive, educative, and qualitative approaches to formative evaluation can facilitate a partnership between evaluators and educational researchers and program managers to generate data useful to inform program implementation and improvement. This partnership is critical, we argue, because it enables an awareness of when to take appropriate action to ensure successful educational programs or "kairos". To illustrate, we use examples from our own evaluation work to highlight how formative evaluation may facilitate opportune moments to (1) define the substance and purpose of a program, (2) develop understanding and awareness of the cultural interpretations of program participants, and (3) show the relevance of stakeholder experiences to program goals. Copyright © 2014 Elsevier Ltd. All rights reserved.

Adolescent Violent Victimization and Precocious Union Formation.

Science.gov (United States)

C Kuhl, Danielle; Warner, David F; Wilczak, Andrew

2012-11-01

This article bridges scholarship in criminology and family sociology by extending arguments about "precocious exits" from adolescence to consider early union formation as a salient outcome of violent victimization for youths. Research indicates that early union formation is associated with several negative outcomes; yet the absence of attention to union formation as a consequence of violent victimization is noteworthy. We address this gap by drawing on life course theory and data from the National Longitudinal Study of Adolescent Health (Add Health) to examine the effect of violent victimization ("street" violence) on the timing of first co-residential union formation-differentiating between marriage and cohabitation-in young adulthood. Estimates from Cox proportional hazard models show that adolescent victims of street violence experience higher rates of first union formation, especially marriage, early in the transition to adulthood; however, this effect declines with age, as such unions become more normative. Importantly, the effect of violent victimization on first union timing is robust to controls for nonviolent delinquency, substance abuse, and violent perpetration. We conclude by discussing directions for future research on the association between violent victimization and coresidential unions with an eye toward the implications of such early union formation for desistance.

Network Configuration Analysis for Formation Flying Satellites

Science.gov (United States)

Knoblock, Eric J.; Wallett, Thomas M.; Konangi, Vijay K.; Bhasin, Kul B.

2001-01-01

The performance of two networks to support autonomous multi-spacecraft formation flying systems is presented. Both systems are comprised of a ten-satellite formation, with one of the satellites designated as the central or 'mother ship.' All data is routed through the mother ship to the terrestrial network. The first system uses a TCP/EP over ATM protocol architecture within the formation, and the second system uses the IEEE 802.11 protocol architecture within the formation. The simulations consist of file transfers using either the File Transfer Protocol (FTP) or the Simple Automatic File Exchange (SAFE) Protocol. The results compare the IP queuing delay, IP queue size and IP processing delay at the mother ship as well as end-to-end delay for both systems. In all cases, using IEEE 802.11 within the formation yields less delay. Also, the throughput exhibited by SAFE is better than FTP.

Renewable Formate from C-H Bond Formation with CO2: Using Iron Carbonyl Clusters as Electrocatalysts.

Science.gov (United States)

Loewen, Natalia D; Neelakantan, Taruna V; Berben, Louise A

2017-09-19

As a society, we are heavily dependent on nonrenewable petroleum-derived fuels and chemical feedstocks. Rapid depletion of these resources and the increasingly evident negative effects of excess atmospheric CO 2 drive our efforts to discover ways of converting excess CO 2 into energy dense chemical fuels through selective C-H bond formation and using renewable energy sources to supply electrons. In this way, a carbon-neutral fuel economy might be realized. To develop a molecular or heterogeneous catalyst for C-H bond formation with CO 2 requires a fundamental understanding of how to generate metal hydrides that selectively donate H - to CO 2 , rather than recombining with H + to liberate H 2 . Our work with a unique series of water-soluble and -stable, low-valent iron electrocatalysts offers mechanistic and thermochemical insights into formate production from CO 2 . Of particular interest are the nitride- and carbide-containing clusters: [Fe 4 N(CO) 12 ] - and its derivatives and [Fe 4 C(CO) 12 ] 2- . In both aqueous and mixed solvent conditions, [Fe 4 N(CO) 12 ] - forms a reduced hydride intermediate, [H-Fe 4 N(CO) 12 ] - , through stepwise electron and proton transfers. This hydride selectively reacts with CO 2 and generates formate with >95% efficiency. The mechanism for this transformation is supported by crystallographic, cyclic voltammetry, and spectroelectrochemical (SEC) evidence. Furthermore, installation of a proton shuttle onto [Fe 4 N(CO) 12 ] - facilitates proton transfer to the active site, successfully intercepting the hydride intermediate before it reacts with CO 2 ; only H 2 is observed in this case. In contrast, isoelectronic [Fe 4 C(CO) 12 ] 2- features a concerted proton-electron transfer mechanism to form [H-Fe 4 C(CO) 12 ] 2- , which is selective for H 2 production even in the presence of CO 2 , in both aqueous and mixed solvent systems. Higher nuclearity clusters were also studied, and all are proton reduction electrocatalysts, but none

Formation of the First Stars and Blackholes

Science.gov (United States)

Yoshida, Naoki

2018-05-01

Cosmic reionization is thought to be initiated by the first generation of stars and blackholes. We review recent progress in theoretical studies of early structure formation. Cosmic structure formation is driven by gravitational instability of primeval density fluctuations left over from Big Bang. At early epochs, there are baryonic streaming motions with significant relative velocity with respect to dark matter. The formation of primordial gas clouds is typically delayed by the streaming motions, but then physical conditions for the so-called direct collapse blackhole formation are realized in proto-galactic halos. We present a promising model in which intermediate mass blackholes are formed as early as z = 30.

Simbol-X Formation Flight and Image Reconstruction

Science.gov (United States)

Civitani, M.; Djalal, S.; Le Duigou, J. M.; La Marle, O.; Chipaux, R.

2009-05-01

Simbol-X is the first operational mission relying on two satellites flying in formation. The dynamics of the telescope, due to the formation flight concept, raises a variety of problematic, like image reconstruction, that can be better evaluated via a simulation tools. We present here the first results obtained with Simulos, simulation tool aimed to study the relative spacecrafts navigation and the weight of the different parameters in image reconstruction and telescope performance evaluation. The simulation relies on attitude and formation flight sensors models, formation flight dynamics and control, mirror model and focal plane model, while the image reconstruction is based on the Line of Sight (LOS) concept.

An anti vimentin antibody promotes tube formation

DEFF Research Database (Denmark)

Jørgensen, Mathias Lindh; Møller, Carina Kjeldahl; Rasmussen, Lasse

2017-01-01

antibody technology, promotes tube formation of endothelial cells in a 2D matrigel assay. By binding vimentin, the antibody increases the tube formation by 21% after 5 hours of incubation. Addition of the antibody directly to cultured endothelial cells does not influence endothelial cell migration...... or proliferation. The enhanced tube formation can be seen for up to 10 hours where after the effect decreases. It is shown that the antibody-binding site is located on the coil 2 domain of vimentin. To our knowledge this is the first study that demonstrates an enhanced tube formation by binding vimentin in a 2D...

HOW GALACTIC ENVIRONMENT REGULATES STAR FORMATION

Energy Technology Data Exchange (ETDEWEB)

Meidt, Sharon E. [Max-Planck-Institut für Astronomie/Königstuhl 17 D-69117 Heidelberg (Germany)

2016-02-10

In a new simple model I reconcile two contradictory views on the factors that determine the rate at which molecular clouds form stars—internal structure versus external, environmental influences—providing a unified picture for the regulation of star formation in galaxies. In the presence of external pressure, the pressure gradient set up within a self-gravitating turbulent (isothermal) cloud leads to a non-uniform density distribution. Thus the local environment of a cloud influences its internal structure. In the simple equilibrium model, the fraction of gas at high density in the cloud interior is determined simply by the cloud surface density, which is itself inherited from the pressure in the immediate surroundings. This idea is tested using measurements of the properties of local clouds, which are found to show remarkable agreement with the simple equilibrium model. The model also naturally predicts the star formation relation observed on cloud scales and at the same time provides a mapping between this relation and the closer-to-linear molecular star formation relation measured on larger scales in galaxies. The key is that pressure regulates not only the molecular content of the ISM but also the cloud surface density. I provide a straightforward prescription for the pressure regulation of star formation that can be directly implemented in numerical models. Predictions for the dense gas fraction and star formation efficiency measured on large-scales within galaxies are also presented, establishing the basis for a new picture of star formation regulated by galactic environment.

SCIFIO: an extensible framework to support scientific image formats.

Science.gov (United States)

Hiner, Mark C; Rueden, Curtis T; Eliceiri, Kevin W

2016-12-07

No gold standard exists in the world of scientific image acquisition; a proliferation of instruments each with its own proprietary data format has made out-of-the-box sharing of that data nearly impossible. In the field of light microscopy, the Bio-Formats library was designed to translate such proprietary data formats to a common, open-source schema, enabling sharing and reproduction of scientific results. While Bio-Formats has proved successful for microscopy images, the greater scientific community was lacking a domain-independent framework for format translation. SCIFIO (SCientific Image Format Input and Output) is presented as a freely available, open-source library unifying the mechanisms of reading and writing image data. The core of SCIFIO is its modular definition of formats, the design of which clearly outlines the components of image I/O to encourage extensibility, facilitated by the dynamic discovery of the SciJava plugin framework. SCIFIO is structured to support coexistence of multiple domain-specific open exchange formats, such as Bio-Formats' OME-TIFF, within a unified environment. SCIFIO is a freely available software library developed to standardize the process of reading and writing scientific image formats.

Complex Formation Control of Large-Scale Intelligent Autonomous Vehicles

Directory of Open Access Journals (Sweden)

Ming Lei

2012-01-01

Full Text Available A new formation framework of large-scale intelligent autonomous vehicles is developed, which can realize complex formations while reducing data exchange. Using the proposed hierarchy formation method and the automatic dividing algorithm, vehicles are automatically divided into leaders and followers by exchanging information via wireless network at initial time. Then, leaders form formation geometric shape by global formation information and followers track their own virtual leaders to form line formation by local information. The formation control laws of leaders and followers are designed based on consensus algorithms. Moreover, collision-avoiding problems are considered and solved using artificial potential functions. Finally, a simulation example that consists of 25 vehicles shows the effectiveness of theory.

Extrasolar planets formation, detection and dynamics

CERN Document Server

Dvorak, Rudolf

2008-01-01

This latest, up-to-date resource for research on extrasolar planets covers formation, dynamics, atmospheres and detection. After a look at the formation of giant planets, the book goes on to discuss the formation and dynamics of planets in resonances, planets in double stars, atmospheres and habitable zones, detection via spectra and transits, and the history and prospects of ESPs as well as satellite projects.Edited by a renowned expert in solar system dynamics with chapters written by the leading experts in the method described -- from the US and Europe -- this is an ideal textbook for g

Star formations rates in the Galaxy

International Nuclear Information System (INIS)

Smith, L.F.; Mezger, P.G.; Biermann, P.

1978-01-01

Data relevant to giant HII regions in the Galaxy are collected. The production rate for Lyman continuum photons by O stars in giant HII regions is 4.7 10 52 s -1 in the whole Galaxy. The corresponding present rate of star formation is M (sun)/yr, of which 74% occurs in main spiral arms, 13% in the interarm region and 13% in the galactic center. The star formation rates, the observed heavy element and deuterium abundances in the solar neighbourhood are compared to model predictions based on star formation proportional to a power (k) of the gas surface density. The mass function is terminated at Msub(u)=100 M (sun) above and M 1 below. Msub(u)=50 M (sun) is also considered. Comparing with data derived from observations a) the star formation rate, b) metal abundances, c) deuterium abundances, and d) colors of the stellar population, we find that models of k=1/2 to 1, and M 1 1 M (sun) are formed together with O and B stars, but under rather special conditions of the interstellar gas, while lower mass stars form wherever dense molecular clouds exist. The high rate of star formation in the galactic center may represent a burst. (orig.) [de

INSTITUTIONAL ENVIRONMENT OF THE AGRICULTURAL MARKET FORMATION PROCESS

Directory of Open Access Journals (Sweden)

S. Revenko

2013-11-01

Full Text Available This article considers institutional aspects of the organized agricultural market formation process. Theoretical base to distinguish institute and institutes is given. In order to find out main influential institutes of the “organization” phenomenon author analyses Ukrainian institutional environment that is under construction process. Author considers main processes which are running during the organized market formation. Author researches theoretical approaches to the institutional staff. In order to structure the most common approaches and theoretical knowledge of this problem author proposes few schemes. Author’s points of view for many questions of the organized market formation process are proposed. Researcher analyzes effectiveness of the institutes and governmental regulation of the agricultural market. Readers can find strategically new approach to the agricultural market formation policy from the governmental point of view. Essence of the socioeconomic formation of agricultural market is considered. Main factors of agriculture market formation are outlined. Agricultural market structural parts consideration systematic approach is proposed. Ineffectiveness of the agriculture market relations without regulation process is proved. The most unfavorable reasons of the agricultural market formation are determined.

Recombinant human bone morphogenetic protein induces bone formation

International Nuclear Information System (INIS)

Wang, E.A.; Rosen, V.; D'Alessandro, J.S.; Bauduy, M.; Cordes, P.; Harada, T.; Israel, D.I.; Hewick, R.M.; Kerns, K.M.; LaPan, P.; Luxenberg, D.P.; McQuaid, D.; Moutsatsos, I.K.; Nove, J.; Wozney, J.M.

1990-01-01

The authors have purified and characterized active recombinant human bone morphogenetic protein (BMP) 2A. Implantation of the recombinant protein in rats showed that a single BMP can induce bone formation in vivo. A dose-response and time-course study using the rat ectopic bone formation assay revealed that implantation of 0.5-115 μg of partially purified recombinant human BMP-2A resulted in cartilage by day 7 and bone formation by day 14. The time at which bone formation occurred was dependent on the amount of BMP-2A implanted; at high doses bone formation could be observed at 5 days. The cartilage- and bone-inductive activity of the recombinant BMP-2A is histologically indistinguishable from that of bone extracts. Thus, recombinant BMP-2A has therapeutic potential to promote de novo bone formation in humans

Formation, Sintering and Removal of Biomass Ash Deposits

DEFF Research Database (Denmark)

Laxminarayan, Yashasvi

conditions in laboratory-scale setups. Deposit formation was simulated in an Entrained Flow Reactor, to investigate the effect of operating conditions and ash chemistry on the rate of deposit formation. Experiments were performed using model biomass fly ash, prepared from mixtures of K2Si4O9, KCl, K2SO4, Ca....... Moreover, biomass ash deposits may cause severe corrosion of boiler surfaces. Therefore, reducing deposit formation and timely deposit removal are essential for optimal boiler operation. The formation, sintering and removal of boiler deposits has been investigated in this PhD project, by simulating boiler...... temperature increased the sticking probability of the fly ash particles/deposit surface, thereby increasing the rate of deposit formation. However, increasing flue gas velocity resulted in a decrease in the deposit formation rate, due to increased particle rebound. Furthermore, it was observed...

Thermoluminescence dating of Rio Claro and Piracununga formations

International Nuclear Information System (INIS)

Ferreira, Sandra Regina; Chang, Maria Rita Caetano

2008-01-01

The Rio Claro and Piracununga formations cover extensive areas of the Paulista Peripheral Depression, dominantly in the region of Rio Claro and Piracununga cities. These units lie over the Corumbatai and Piramboia formations, exhibiting discordant contacts. The Rio Claro and Piracununga formations are composed of fine to medium sand facies, showing local cross-stratifications and parallel beddings with thin interbeddings of mud and gravel. These sands were dated by the Thermoluminescence Method, which indicated they were from the Pleistocene age. The oldest age (745,000 years BP) was found in deposits of the Rio Claro Formation; the other ages varied from 400,000 years BP to 145,000 years BP, for both formations. The youngest age (15,000 years BP - close to Pleistocene/ Holocene limit) was found in colluvial deposits, which rest on the Piracununga Formation. (author)

Temperature controlled formation of lead/acid batteries

Science.gov (United States)

Bungardt, M.

At present, standard formation programs have to accommodate the worst case. This is important, especially in respect of variations in climatic conditions. The standard must be set so that during the hottest weather periods the maximum electrolyte temperature is not exceeded. As this value is defined not only by the desired properties and the recipe of the active mass, but also by type and size of the separators and by the dimensions of the plates, general rules cannot be formulated. It is considered to be advantageous to introduce limiting data for the maximum temperature into a general formation program. The latter is defined so that under normal to good ambient conditions the shortest formation time is achieved. If required, the temperature control will reduce the currents employed in the different steps, according to need, and will extend the formation time accordingly. With computer-controlled formation, these parameters can be readily adjusted to suit each type of battery and can also be reset according to modifications in the preceding processing steps. Such a procedure ensures that: (i) the formation time is minimum under the given ambient conditions; (ii) in the event of malpractice ( e.g. actual program not fitting to size) the batteries will not be destroyed; (iii) the energy consumption is minimized (note, high electrolyte temperature leads to excess gassing). These features are incorporated in the BA/FOS-500 battery formation system developed by Digatron. The operational characteristics of this system are listed in Table 1.

Experimental study upon the effect of irradiation on callus formation of fracture. Observation of vascular alteration and callus formation

Energy Technology Data Exchange (ETDEWEB)

Saigusa, F [Nippon Dental Coll., Tokyo

1981-02-01

Irradiation effects on callus formation after bone fracture were studied in rats with fractured right lower extremity. Follow-up study was continued for 112 days since 3000 rad was irradiated to the fractured site 3 days after bone fracture. Callus formation was noted in both of the outer and inner part (bone marrow) of the diaphysis before 14 days after bone fracture, but it was slow and sparse compared with that of non-irradiated group. Callus formation tended to disappear gradually from the outside of the diaphysis after 28 days after bone fracture. Strong disturbance was found in the surrounding vascular system at this time. Inside of the diaphysis, callus formation was restricted the end of the fracture, where lamellar calluses fused together. Changes in vascular system remained until 56 days after bone fracture. Vascular distribution was most dense 28 days after bone fracture. In many of the calluses which have established fusion, findings suggested excessive calcification in the trabeculae. Vascular distribution at this time was sparse, vascular formation was markedly suppressed in the bone marrow, and very little vascular formation was found in the fractured edges of the bone.

Grammar-Based Specification and Parsing of Binary File Formats

Directory of Open Access Journals (Sweden)

William Underwood

2012-03-01

Full Text Available The capability to validate and view or play binary file formats, as well as to convert binary file formats to standard or current file formats, is critically important to the preservation of digital data and records. This paper describes the extension of context-free grammars from strings to binary files. Binary files are arrays of data types, such as long and short integers, floating-point numbers and pointers, as well as characters. The concept of an attribute grammar is extended to these context-free array grammars. This attribute grammar has been used to define a number of chunk-based and directory-based binary file formats. A parser generator has been used with some of these grammars to generate syntax checkers (recognizers for validating binary file formats. Among the potential benefits of an attribute grammar-based approach to specification and parsing of binary file formats is that attribute grammars not only support format validation, but support generation of error messages during validation of format, validation of semantic constraints, attribute value extraction (characterization, generation of viewers or players for file formats, and conversion to current or standard file formats. The significance of these results is that with these extensions to core computer science concepts, traditional parser/compiler technologies can potentially be used as a part of a general, cost effective curation strategy for binary file formats.

General certification procedure of formation organizations

CERN Document Server

Int. At. Energy Agency, Wien

2002-01-01

This document presents the procedure dealing with the certification of formation organizations dispensing the formation and the risks prevention to the personnel of A or B category in nuclear facilities. This certification proves the organization ability to satisfy the ''F'' specification of the CEFRI. (A.L.B.)

Spur Reaction Model of Positronium Formation

DEFF Research Database (Denmark)

Mogensen, O. E.

1974-01-01

A new model of positronium (Ps) formation is proposed. Positronium is assumed to be formed by a reaction between a positron and an electron in the positron spur. Ps formation must compete with electron‐ion recombination and electron or positron reactions with solvent molecules and scavenger...

Exoplanets Detection, Formation, Properties, Habitability

CERN Document Server

Mason, John W

2008-01-01

This edited, multi-author volume will be an invaluable introduction and reference to all key aspects in the field of exoplanet research. The reviews cover: Detection methods and properties of known exoplanets, Detection of extrasolar planets by gravitational microlensing. The formation and evolution of terrestrial planets in protoplanetary and debris disks. The brown dwarf-exoplanet connection. Formation, migration mechanisms and properties of hot Jupiters. Dynamics of multiple exoplanet systems. Doppler exoplanet surveys. Searching for exoplanets in the stellar graveyard. Formation and habitability of extra solar planets in multiple star systems. Exoplanet habitats and the possibilities for life. Moons of exoplanets: habitats for life. Contributing authors: •Rory Barnes •David P. Bennett •Jian Ge •Nader Haghighipour •Patrick Irwin •Hugh Jones •Victoria Meadows •Stanimir Metchev •I. Neill Reid •George Rieke •Caleb Scharf •Steinn Sigurdsson

Modularity in New Market Formation

DEFF Research Database (Denmark)

Sanchez, Ron; Hang, Chang Chieh

2017-01-01

In this paper we appraise the ways in which use of closed-system proprietary product architectures versus open-system modular product architectures is likely to influence the dynamics and trajectory of new product market formation. We compare the evolutions of new markets in China for gas......-powered two-wheeled vehicles (G2WVs) based (initially) on closed-system proprietary architectures and for electric-powered two-wheeled vehicles (E2WVs) based on open-system modular architectures. We draw on this comparison to suggest ways in which the use of the two different kinds of architectures...... as the basis for new kinds of products may result in very different patterns and speeds of new market formation. We then suggest some key implications of the different dynamics of market formation associated with open-system modular architectures for both the competence-based strategic management (CBSM...

Star Cluster Structure from Hierarchical Star Formation

Science.gov (United States)

Grudic, Michael; Hopkins, Philip; Murray, Norman; Lamberts, Astrid; Guszejnov, David; Schmitz, Denise; Boylan-Kolchin, Michael

2018-01-01

Young massive star clusters (YMCs) spanning 104-108 M⊙ in mass generally have similar radial surface density profiles, with an outer power-law index typically between -2 and -3. This similarity suggests that they are shaped by scale-free physics at formation. Recent multi-physics MHD simulations of YMC formation have also produced populations of YMCs with this type of surface density profile, allowing us to narrow down the physics necessary to form a YMC with properties as observed. We show that the shallow density profiles of YMCs are a natural result of phase-space mixing that occurs as they assemble from the clumpy, hierarchically-clustered configuration imprinted by the star formation process. We develop physical intuition for this process via analytic arguments and collisionless N-body experiments, elucidating the connection between star formation physics and star cluster structure. This has implications for the early-time structure and evolution of proto-globular clusters, and prospects for simulating their formation in the FIRE cosmological zoom-in simulations.

Septum formation of the lateral ventricles

International Nuclear Information System (INIS)

Celik, Hakan H.; Aldur, Mustafa M.; Tatar, I.; Tascioglu, A.B.

2005-01-01

In an MRI study examining anomalies of the septum pellucidum in 505 cases, we detected bilateral septum formation of the lateral ventricles in a 17-months-old-baby. In this study, we evaluate 505 (242 males and 263 females) patients referred to the Emaray Imaging Center, Ankara, Turkey with various prediagnoses. We specially selected all the cases from a non-psychotic population. We obtained MRI scans on a 1-Tesla imager (Picker International, Highland Heights, Ohio, USA), with slices of 5 and 6 mm thickness. In the axial and coronal sections, we observed septum formation laterally between the anterior horn and the ventricular body of the lateral ventricles. Radio opaque septum formations started from the caudate nucleus and stretched to the genu of the corpus callosum. There was a second septum formation between the posterior horn and the ventricular body of the right lateral ventricle. It started from the caudate nucleus and stretched to the cavum vergae. (author)

Theoretical Aspects of Enterprise Business Strategy Formation

OpenAIRE

Valentinavičius, Stasys

2009-01-01

The paper presents interpretations of business strategy concept and analyses strategy planning and formation, models. The concept of business strategy is revised and formulated considering various authors approaches. Analysis of business strategy formation process – steps of development and management, selection of strategy type – is based on presented strategy planning models. The aspects of enterprise business and investment strategy formation, coordination and valuation are analysed. The s...

Formation rate of natural gas hydrate

Energy Technology Data Exchange (ETDEWEB)

Mork, Marit

2002-07-01

The rate of methane hydrate and natural gas hydrate formation was measured in a 9.5 litre stirred tank reactor of standard design. The experiments were performed to better understand the performance and scale-up of a reactor for continuous production of natural gas hydrates. The hydrate formation rate was measured at steady-state conditions at pressures between 70 and 90 bar and temperatures between 7 and 15 deg C. Between 44 and 56 % of the gas continuously supplied to the reactor was converted to hydrate. The experimental results show that the rate of hydrate formation is strongly influenced by gas injection rate and pressure. The effect of stirring rate is less significant and subcooling has no observable effect on the formation rate. Hydrate crystal concentration and gas composition do not influence the hydrate formation rate. Observations of produced hydrate crystals indicate that the crystals are elongated, about 5 micron in diameter and 10 micron long. Analysis of the results shows that the rate of hydrate formation is dominated by gas-liquid mass transfer. A mass transfer model, the bubble-to-crystal model, was developed for the hydrate formation rate in a continuous stirred tank reactor, given in terms of concentration driving force and an overall mass transfer coefficient. The driving force is the difference between the gas concentration at the gas-liquid interface and at the hydrate crystal surface. These concentrations correspond to the solubility of gas in water at experimental temperature and pressure and the solubility of gas at hydrate equilibrium temperature and experimental pressure, respectively. The overall mass transfer coefficient is expressed in terms of superficial gas velocity and impeller power consumption, parameters commonly used in study of stirred tank reactors. Experiments and modeling show that the stirred tank reactor has a considerable potential for increased production capacity. However, at higher hydrate production rates the

The multifaceted planetesimal formation process

DEFF Research Database (Denmark)

Johansen, Anders; Blum, Jürgen; Tanaka, Hidekazu

2013-01-01

Accumulation of dust and ice particles into planetesimals is an important step in the planet formation process. Planetesimals are the seeds of both terrestrial planets and the solid cores of gas and ice giants forming by core accretion. Left-over planetesimals in the form of asteroids, trans...... for planetesimal formation where particle growth starts unaided by self-gravity but later proceeds inside gravitationally collapsing pebble clumps to form planetesimals with a wide range of sizes....

Ministerial formation of theological students through distance education

Directory of Open Access Journals (Sweden)

Marilyn Naidoo

2012-02-01

Full Text Available Ministerial formation is a multifaceted activity involving critical thinking, the acquisition of knowledge, skills development, religious identity formation and the development of ministerial and spiritual maturity expected of church ministers. Education is not merely the accumulation of a prescribed set of academic credits but includes the holistic formation of all aspects of the individual. However, theological educators are concerned about the capacity to foster such values and skills in the distance and electronic environment. Some see distance education as ‘distancing’ the students in more significant ways than simply geographic distance. These issues are of fundamental importance for they reflect the deeper convictions of theologians that distance education may not be a suitable medium for ministerial formation. This article creates a conceptual map of the theological and pedagogical challenges for ministerial formation and highlights how the possibility of formation is being carried out in the distance-learning environment.

Formation and evolution of compact binaries

NARCIS (Netherlands)

Sluijs, Marcel Vincent van der

2006-01-01

In this thesis we investigate the formation and evolution of compact binaries. Chapters 2 through 4 deal with the formation of luminous, ultra-compact X-ray binaries in globular clusters. We show that the proposed scenario of magnetic capture produces too few ultra-compact X-ray binaries to explain

Combustion chemistry and formation of pollutants; Chimie de la combustion et formation des polluants

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-31

This book of proceedings reports on 7 papers on combustion chemistry and formation of pollutants presented during the workshop organized by the `Combustion and Flames` section of the French society of thermal engineers. The chemistry of combustion is analyzed in various situations such as: turbojet engines, spark ignition engines, industrial burners, gas turbines etc... Numerical simulation is used to understand the physico-chemical processes involved in combustion, to describe the kinetics of oxidation, combustion and flame propagation, and to predict the formation of pollutants. (J.S.)

Converting Taxonomic Descriptions to New Digital Formats

Directory of Open Access Journals (Sweden)

Hong Cui

2008-01-01

Full Text Available Abstract.--The majority of taxonomic descriptions is currently in print format. The majority of digital descriptions are in formats such as DOC, HTML, or PDF and for human readers. These formats do not convey rich semantics in taxonomic descriptions for computer-aided process. Newer digital formats such as XML and RDF accommodate semantic annotations that allow computers to process the rich semantics on human's behalf, thus open up opportunities for a wide range of innovative usages of taxonomic descriptions, such as searching in more precise and flexible ways, integrating with gnomic and geographic information, generating taxonomic keys automatically, and text data mining and information visualization etc. This paper discusses the challenges in automated conversion of multiple collections of descriptions to XML format and reports an automated system, MARTT. MARTT is a machine-learning system that makes use of training examples to tag new descriptions into XML format. A number of utilities are implemented as solutions to the challenges. The utilities are used to reduce the effort for training example preparation, to facilitate the creation of a comprehensive schema, and to predict system performance on a new collection of descriptions. The system has been tested with several plant and alga taxonomic publications including Flora of China and Flora of North America.

Superclusters and galaxy formation

International Nuclear Information System (INIS)

Einasto, J.; Joeveer, M.; Saar, E.

1979-01-01

The spatial distribution of Galaxies and Galaxy congestions in the southern galactic hemisphere is studied. The rich galaxy congestions, containing many elliptic Galaxies and radiogalaxies, are linked with each other by chains of scanty congestions with moderate content of elliptic Galaxies and radiogalaxies. The flat formation, linking the density pikes and the intermediate chains, can reasonably be called supercongestion. In the central region of supercongestions there is a thin layer of Galaxies consisting of only spiral Galaxies. The neighbouring supercongestions touch each other, while the intersupercongestion space contains no Galaxy congestions and almost no Galaxies. It is shown that such a structure was, apparently, formed before the formation of Galaxies

Implication of formative assessment practices among mathematics teacher

Science.gov (United States)

Samah, Mas Norbany binti Abu; Tajudin, Nor'ain binti Mohd

2017-05-01

Formative assessment of school-based assessment (SBA) is implemented in schools as a move to improve the National Education Assessment System (NEAS). Formative assessment focuses on assessment for learning. There are various types of formative assessment instruments used by teachers of mathematics, namely the form of observation, questioning protocols, worksheets and quizzes. This study aims to help teachers improve skills in formative assessments during the teaching and learning (t&l) Mathematics. One mathematics teacher had been chosen as the study participants. The collecting data using document analysis, observation and interviews. Data were analyzed narrative and assessments can help teachers implement PBS. Formative assessment is conducted to improve the skills of students in t&l effectively.

MILLIMETER WAVE SPECTRUM AND ASTRONOMICAL SEARCH FOR VINYL FORMATE

Energy Technology Data Exchange (ETDEWEB)

Alonso, E. R.; Kolesniková, L.; Cabezas, C.; Alonso, J. L. [Grupo de Espectroscopia Molecular (GEM), Edificio Quifima, Área de Química-Física, Laboratorios de Espectroscopia y Bioespectroscopia, Parque Científico UVa, Unidad Asociada CSIC, Universidad de Valladolid, E-47011 Valladolid (Spain); Tercero, B.; Cernicharo, J. [Grupo de Astrofísica Molecular, ICMM-CSIC, C/Sor Juana Inés de la Cruz 3, E-28049 Cantoblanco (Spain); Guillemin, J.-C. [Institut des Sciences Chimiques de Rennes, École Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, F-35708 Rennes Cedex 7 (France)

2016-11-20

Previous detections of methyl and ethyl formate make other small substituted formates potential candidates for observation in the interstellar medium. Among them, vinyl formate is one of the simplest unsaturated carboxylic ester. The aim of this work is to provide direct experimental frequencies of the ground vibrational state of vinyl formate in a large spectral range for astrophysical use. The room-temperature rotational spectrum of vinyl formate has been measured from 80 to 360 GHz and analyzed in terms of Watson’s semirigid rotor Hamiltonian. Two thousand six hundred transitions within J = 3–88 and K {sub a} = 0–28 were assigned to the most stable conformer of vinyl formate and a new set of spectroscopic constants was accurately determined. Spectral features of vinyl formate were then searched for in Orion KL, Sgr B2(N), B1-b, and TMC-1 molecular clouds. Upper limits to the column density of vinyl formate are provided.

On the formation of sulphuric acid – amine clusters in varying atmospheric conditions and its influence on atmospheric new particle formation

Directory of Open Access Journals (Sweden)

I. K. Ortega

2012-10-01

Full Text Available Sulphuric acid is a key component in atmospheric new particle formation. However, sulphuric acid alone does not form stable enough clusters to initiate particle formation in atmospheric conditions. Strong bases, such as amines, have been suggested to stabilize sulphuric acid clusters and thus participate in particle formation. We modelled the formation rate of clusters with two sulphuric acid and two amine molecules (JA2B2 at varying atmospherically relevant conditions with respect to concentrations of sulphuric acid ([H2SO4], dimethylamine ([DMA] and trimethylamine ([TMA], temperature and relative humidity (RH. We also tested how the model results change if we assume that the clusters with two sulphuric acid and two amine molecules would act as seeds for heterogeneous nucleation of organic vapours (other than amines with higher atmospheric concentrations than sulphuric acid. The modelled formation rates JA2B2 were functions of sulphuric acid concentration with close to quadratic dependence, which is in good agreement with atmospheric observations of the connection between the particle formation rate and sulphuric acid concentration. The coefficients KA2B2 connecting the cluster formation rate and sulphuric acid concentrations as JA2B2=KA2B2[H2SO4]2 turned out to depend also on amine concentrations, temperature and relative humidity. We compared the modelled coefficients KA2B2 with the corresponding coefficients calculated from the atmospheric observations (Kobs from environments with varying temperatures and levels of anthropogenic influence. By taking into account the modelled behaviour of JA2B2 as a function of [H2SO4], temperature and RH, the atmospheric particle formation rate was reproduced more closely than with the traditional semi-empirical formulae based on sulphuric acid concentration only. The formation rates of clusters with two sulphuric acid and two amine molecules with different amine compositions (DMA or TMA or one of both had

Fostering Spiritual Formation of Millennials in Christian Schools

Science.gov (United States)

Horan, Anne Puidk

2017-01-01

Christian education seeks to foster millennials' spiritual formation to equip them for future challenges and to benefit society. Using nonexperimental mixed methods, 504 secondary educators revealed what spiritual formation programs their schools implement and their perceptions about millennial spiritual formation. Descriptive analysis showed that…

Inhibition of the anaerobic acetate degradation by formate

OpenAIRE

Guyot, Jean-Pierre; Ramirez, F.

1989-01-01

Granular sludge from an UASB reactor fed with VFA showed a very low affinity for formate which provide little support to the theory of interspecies formate transfer. It is shown that formate can inhibit acetate degradation by anaerobic sludge. (Résumé d'auteur)

The formation mechanism of lactones in Gouda cheese

NARCIS (Netherlands)

Alewijn, M.; Smit, B.; Sliwinski, E.L.; Wouters, J.T.M.

2007-01-01

Lactones are fat-derived aroma compounds, but the formation mechanism of these compounds during ripening of Gouda cheese is unknown. Both enzymatic and chemical formation pathways were investigated in this study. Lactone formation from milk triglycerides or free fatty acids by lactic acid bacteria

Aggregate formation in 3D turbulent-like flows

NARCIS (Netherlands)

Dominguez, A.; Clercx, H.J.H.

2006-01-01

Aggregate formation is an important process in industrial and environmental turbulent flows. In oceans turbulence play an important role on Marine Snow (aggregate) formation. For a proper description, the study of aggregate formation in turbulent flows requires a particle based model i.e. following

Time-Dependent Dust Formation in Novae

Directory of Open Access Journals (Sweden)

Kyung-Won Suh

1991-06-01

Full Text Available The dust formation processes in novae are investigated with close attention to recent infrared observations. Using mainly the classical nucleation theory, we have calculated the time scales of dust formation and growth in the environments of novae. Those time scales roughly resemble the typical observations. We have classified the dust-forming novae into three classes according to their explosion properties and the thermodynamic properties of dust grains. Oxygen grains from much later than carbon grains because of their thermodynamic properties. The effect of grain formation to the efficiency of stellar winds to drive the material outward is tested with newly obtained Planck mean values of dust grains.

Formation enthalpy of alkali-borosilicate glass

International Nuclear Information System (INIS)

Borisova, N.V.; Ushakov, V.M.

1991-01-01

Temperature dependence of formation enthalpy of glass of the composition 0.0438Na 2 O-0.0385K 2 O-0.3394B 2 O 3 -0.5783SiO 2 was determined using the method of high-temperature colorimetry-dissolution, mixing and differential scanning calorimetry. The glass considered has liquation nature-two-vitrification ranges at 713 K and 817 K are detected. The brightening point is 922 K. The calculation of formation enthalpy using the method of partial heat capacities is made in the temperature range of 973-1473 K. Formation enthalpy does not depend on temperature in the temperature range of 298-1273 K

New method for determination of star formation history

OpenAIRE

Čeponis, Marius

2017-01-01

A New Method for Determination of Star Formation History Without stars there would not be any life and us. Almost all elements in our bodies are made in stars. Yet we still don‘t fully understand all the processes governing formation and evolution of stellar systems. Their star formation histories really help in trying to understand these processes. In this work a new Bayesian method for determination of star formation history is proposed. This method uses photometric data of resolved stars a...

Efficient stereoscopic contents file format on the basis of ISO base media file format

Science.gov (United States)

Kim, Kyuheon; Lee, Jangwon; Suh, Doug Young; Park, Gwang Hoon

2009-02-01

A lot of 3D contents haven been widely used for multimedia services, however, real 3D video contents have been adopted for a limited applications such as a specially designed 3D cinema. This is because of the difficulty of capturing real 3D video contents and the limitation of display devices available in a market. However, diverse types of display devices for stereoscopic video contents for real 3D video contents have been recently released in a market. Especially, a mobile phone with a stereoscopic camera has been released in a market, which provides a user as a consumer to have more realistic experiences without glasses, and also, as a content creator to take stereoscopic images or record the stereoscopic video contents. However, a user can only store and display these acquired stereoscopic contents with his/her own devices due to the non-existence of a common file format for these contents. This limitation causes a user not share his/her contents with any other users, which makes it difficult the relevant market to stereoscopic contents is getting expanded. Therefore, this paper proposes the common file format on the basis of ISO base media file format for stereoscopic contents, which enables users to store and exchange pure stereoscopic contents. This technology is also currently under development for an international standard of MPEG as being called as a stereoscopic video application format.

Production of Monoclonal Antibodies Specific for Progesterone, Estradiole by Simultaneous Injection of Different Steroids

OpenAIRE

YÜCEL, Fatima ŞAHİNGÖZ

2014-01-01

We report here the development of hybrid cells producing monoclonal antibodies specific for two different steroid hormones with mixed immunization using hybridoma technology. BALB/c mice were immunized with a mixture of three steroid antigens: progesterone, estradiole and testosterone linked to bovine serum albumine. These mice were used for fusion. In the two fusion experiments, ELISA tests showed that among 645 wells only 2 hybrids reacted with progesterone (MAM 3C2, MAM 3E3) and one o...

Calcium Channels: Structure and Function (Annals of the New York Academy of Sciences. Volume 560)

Science.gov (United States)

1989-06-26

overnight (370C) with 0.5 kg DHPR complex. Mab#78 concentration was varied as indicated. (0), Hybridoma culture supernatant (1% fetal calf serum); (0...METHFESSEL & B. SAKMANN. 1986. Molecular distinction between fetal and adult forms of muscle acetylcholine receptor. Nature 321: 406-411. 23. IMoTo...nteLmetEtnmyasthenic syndrome. atbyonp npicalumAnne iN. thed mos. Thsiolm. 6. LEAiio, . ., G.O-VS C. ER & D. W.-WRAY. 198 7. Selectiveisa tion of Lacumcam-lsi muert

A Unique Report: Development of Super Anti-Human IgG Monoclone with Optical Density Over Than 3

OpenAIRE

Aghebati Maleki, Leili; Baradaran, Behzad; Abdolalizadeh, Jalal; Ezzatifar, Fatemeh; Majidi, Jafar

2013-01-01

Purpose: Monoclonal antibodies and related conjugates are key reagents used in biomedical researches as well as, in treatment, purification and diagnosis of infectious and non- infectious diseases. Methods: Balb/c mice were immunized with purified human IgG. Spleen cells of the most immune mouse were fused with SP2/0 in the presence of Poly Ethylene Glycol (PEG). Supernatant of hybridoma cells was screened for detection of antibody by ELISA. Then, the sample was assessed for cross-reactivity ...

Improving food and agricultural production. Thailand. Application on monoclonal antibodies for progesterone measurement

International Nuclear Information System (INIS)

Butcher, G.W.

1991-01-01

The duties of the mission were to provide instructions on the maintenance of hybridoma cell lines and their culture and the harvesting of monoclonal antibodies; to assist the counterparts in Thailand to develop work plans for the use of monoclonal antibodies in radioimmunoassay measurements of progesterone; and to assess the need for and feasibility of establishing a laboratory for producing monoclonal antibodies directed against progesterone. The report contains a summary of the activities performed in fulfillment of these duties

Monoclonal antibody against Porphyromonas (Bacteroides) endodontalis lipopolysaccharide and application of the antibody for direct identification of the species.

OpenAIRE

Hanazawa, S; Sagiya, T; Kitami, H; Ohta, K; Nishikawa, H; Kitano, S

1991-01-01

The aim of the present study was to develop a monoclonal antibody that recognizes the shared antigen of Porphyromonas endodontalis so that we could use the antibody in direct identification and detection of P. endodontalis in infectious material from apical periodontal patients. We established a hybridoma cell line producing monoclonal antibody (BEB5) specific for P. endodontalis. BEB5 antibody reacted with all of the P. endodontalis strains tested, but not with any of the other black-pigment...

Cosmic strings and galaxy formation

Science.gov (United States)

Bertschinger, Edmund

1989-01-01

The cosmogonical model proposed by Zel'dovich and Vilenkin (1981), in which superconducting cosmic strings act as seeds for the origin of structure in the universe, is discussed, summarizing the results of recent theoretical investigations. Consideration is given to the formation of cosmic strings, the microscopic structure of strings, gravitational effects, cosmic string evolution, and the formation of galaxies and large-scale structure. Simulation results are presented in graphs, and several outstanding issues are listed and briefly characterized.

Star formation in evolving molecular clouds

Science.gov (United States)

Völschow, M.; Banerjee, R.; Körtgen, B.

2017-09-01

Molecular clouds are the principle stellar nurseries of our universe; they thus remain a focus of both observational and theoretical studies. From observations, some of the key properties of molecular clouds are well known but many questions regarding their evolution and star formation activity remain open. While numerical simulations feature a large number and complexity of involved physical processes, this plethora of effects may hide the fundamentals that determine the evolution of molecular clouds and enable the formation of stars. Purely analytical models, on the other hand, tend to suffer from rough approximations or a lack of completeness, limiting their predictive power. In this paper, we present a model that incorporates central concepts of astrophysics as well as reliable results from recent simulations of molecular clouds and their evolutionary paths. Based on that, we construct a self-consistent semi-analytical framework that describes the formation, evolution, and star formation activity of molecular clouds, including a number of feedback effects to account for the complex processes inside those objects. The final equation system is solved numerically but at much lower computational expense than, for example, hydrodynamical descriptions of comparable systems. The model presented in this paper agrees well with a broad range of observational results, showing that molecular cloud evolution can be understood as an interplay between accretion, global collapse, star formation, and stellar feedback.

Delayed star formation in isolated dwarf galaxies: Hubble space telescope star formation history of the Aquarius dwarf irregular

Energy Technology Data Exchange (ETDEWEB)

Cole, Andrew A. [School of Physical Sciences, University of Tasmania, Private Bag 37, Hobart, Tasmania, 7001 Australia (Australia); Weisz, Daniel R. [Department of Astronomy, University of California at Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Dolphin, Andrew E. [Raytheon, 1151 East Hermans Road, Tucson, AZ 85706 (United States); Skillman, Evan D. [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55441 (United States); McConnachie, Alan W. [NRC Herzberg Institute of Astrophysics, Dominion Astrophysical Observatory, Victoria, BC, V9E 2E7 Canada (Canada); Brooks, Alyson M. [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Leaman, Ryan, E-mail: andrew.cole@utas.edu.au, E-mail: drw@ucsc.edu, E-mail: adolphin@raytheon.com, E-mail: skillman@astro.umn.edu, E-mail: alan.mcconnachie@nrc-cnrc.gc.ca, E-mail: abrooks@physics.rutgers.edu, E-mail: rleaman@iac.es [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain)

2014-11-01

We have obtained deep images of the highly isolated (d = 1 Mpc) Aquarius dwarf irregular galaxy (DDO 210) with the Hubble Space Telescope Advanced Camera for Surveys. The resulting color-magnitude diagram (CMD) reaches more than a magnitude below the oldest main-sequence turnoff, allowing us to derive the star formation history (SFH) over the entire lifetime of the galaxy with a timing precision of ≈10% of the lookback time. Using a maximum likelihood fit to the CMD we find that only ≈10% of all star formation in Aquarius took place more than 10 Gyr ago (lookback time equivalent to redshift z ≈ 2). The star formation rate increased dramatically ≈6-8 Gyr ago (z ≈ 0.7-1.1) and then declined until the present time. The only known galaxy with a more extreme confirmed delay in star formation is Leo A, a galaxy of similar M {sub H} {sub I}/M {sub *}, dynamical mass, mean metallicity, and degree of isolation. The delayed stellar mass growth in these galaxies does not track the mean dark matter accretion rate from CDM simulations. The similarities between Leo A and Aquarius suggest that if gas is not removed from dwarf galaxies by interactions or feedback, it can linger for several gigayears without cooling in sufficient quantity to form stars efficiently. We discuss possible causes for the delay in star formation including suppression by reionization and late-time mergers. We find reasonable agreement between our measured SFHs and select cosmological simulations of isolated dwarfs. Because star formation and merger processes are both stochastic in nature, delayed star formation in various degrees is predicted to be a characteristic (but not a universal) feature of isolated small galaxies.

Problems of Kazakh Literary Criticism Formation

Directory of Open Access Journals (Sweden)

Zhandos Smagulov

2013-01-01

Full Text Available Тhe article is concerned with the problem of scientific research of Kazakh literature formation in national science. Kazakh literature, having long history of formation is classified by periods. Besides, the article thoroughly considers the principles of the study of methodology, theory, history of spiritual heritage in Kazakh literary criticism

The Role of Trust in Costly Network Formation

NARCIS (Netherlands)

Gilles, R.P.; Sarangi, S.

2003-01-01

We consider game theoretic models of social network formation.In this paper we limit our investigation to game theoretic models of network formation that are based on individual actions only.Our approach is based on three simple and realistic principles: (1) Link formation is a binary process of

Star formation in the outskirts of disk galaxies

NARCIS (Netherlands)

Ferguson, AMN

2002-01-01

The far outer regions of galactic disks allow an important probe of both star formation and galaxy formation. I discuss how observations of HII regions in these low gas density, low metallicity environments can shed light on the physical processes which drive galactic star formation. The history of

Formation of stars and stellar clusters in galactic environment

OpenAIRE

Smilgys, Romas

2018-01-01

Star and stellar cluster formation in spiral galaxies is one of the biggest questions of astrophysics. In this thesis, I study how star formation, and the formation of stellar clusters, proceeds using SPH simulations. These simulations model a region of 400 pc and 10⁷ solar masses. Star formation is modelled through the use of sink particles which represent small groups of stars. Star formation occurs in high density regions, created by galactic spiral arm passage. The spiral shock compresses...

A Faculty Toolkit for Formative Assessment in Pharmacy Education.

Science.gov (United States)

DiVall, Margarita V; Alston, Greg L; Bird, Eleanora; Buring, Shauna M; Kelley, Katherine A; Murphy, Nanci L; Schlesselman, Lauren S; Stowe, Cindy D; Szilagyi, Julianna E

2014-11-15

This paper aims to increase understanding and appreciation of formative assessment and its role in improving student outcomes and the instructional process, while educating faculty on formative techniques readily adaptable to various educational settings. Included are a definition of formative assessment and the distinction between formative and summative assessment. Various formative assessment strategies to evaluate student learning in classroom, laboratory, experiential, and interprofessional education settings are discussed. The role of reflective writing and portfolios, as well as the role of technology in formative assessment, are described. The paper also offers advice for formative assessment of faculty teaching. In conclusion, the authors emphasize the importance of creating a culture of assessment that embraces the concept of 360-degree assessment in both the development of a student's ability to demonstrate achievement of educational outcomes and a faculty member's ability to become an effective educator.

Formatting Open Science: agilely creating multiple document formats for academic manuscripts with Pandoc Scholar

Directory of Open Access Journals (Sweden)

Albert Krewinkel

2017-05-01

Full Text Available The timely publication of scientific results is essential for dynamic advances in science. The ubiquitous availability of computers which are connected to a global network made the rapid and low-cost distribution of information through electronic channels possible. New concepts, such as Open Access publishing and preprint servers are currently changing the traditional print media business towards a community-driven peer production. However, the cost of scientific literature generation, which is either charged to readers, authors or sponsors, is still high. The main active participants in the authoring and evaluation of scientific manuscripts are volunteers, and the cost for online publishing infrastructure is close to negligible. A major time and cost factor is the formatting of manuscripts in the production stage. In this article we demonstrate the feasibility of writing scientific manuscripts in plain markdown (MD text files, which can be easily converted into common publication formats, such as PDF, HTML or EPUB, using Pandoc. The simple syntax of Markdown assures the long-term readability of raw files and the development of software and workflows. We show the implementation of typical elements of scientific manuscripts—formulas, tables, code blocks and citations—and present tools for editing, collaborative writing and version control. We give an example on how to prepare a manuscript with distinct output formats, a DOCX file for submission to a journal, and a LATEX/PDF version for deposition as a PeerJ preprint. Further, we implemented new features for supporting ‘semantic web’ applications, such as the ‘journal article tag suite’—JATS, and the ‘citation typing ontology’—CiTO standard. Reducing the work spent on manuscript formatting translates directly to time and cost savings for writers, publishers, readers and sponsors. Therefore, the adoption of the MD format contributes to the agile production of open science

Self-regulating star formation and disk structure

International Nuclear Information System (INIS)

Dopita, M.A.

1987-01-01

Star formation processes determine the disk structure of galaxies. Stars heavier than about 1 solar mass determine the chemical evolution of the system and are produced at a rate which maintains (by the momentum input of the stars) the phase structure, pressure, and vertical velocity dispersion of the gas. Low mass stars are produced quiescently within molecular clouds, and their associated T-Tauri winds maintain the support of molecular clouds and regulate the star formation rate. Inefficient cooling suppresses this mode of star formation at low metallicity. Applied to the solar neighborhood, such a model can account for age/metallicity relationships, the increase in the O/Fe ratio at low metallicity, the paucity of metal-poor G and K dwarf stars, the missing mass in the disk and, possibly, the existence of a metal-poor thick disk. For other galaxies, it accounts for constant w-velocity dispersion of the gas, the relationship between gas content and specific rates of star formation, the surface brightness/metallicity relationship and for the shallow radial gradients in both star formation rates and HI content. 71 references

Requirements for a next generation nuclear data format

International Nuclear Information System (INIS)

Archier, Pascal; Jouanne, Cedric; Peneliau, Yannick; Saint-Jean, Cyrille de; Trama, Jean-Christophe; Becky, Bret; Cullen, D.E. Red; Mattoony, Caleb; McNabb, Dennis; Brownyz, David; Herman, Michal; Johnson, Timothy; Sonzogni, Alejandro; Cabellos, Oscar; Capote Noy, Roberto; Forrest, Robin; Trkov, Andrej; Zerkiny, Viktor; Go, Chiba; Conliny, Jeremy Lloyd; Kahler, A.H. Skip; Talouy, Patrick; Whitey, Morgan C.; Cornock, Mark; Coste-Delclaux, Mireille; Malvagi, Fausto; Dunn, Michael; Leal, Luiz; Pigni, Marco; Wiarda, Dorothea; Dupont, Emmeric; Fischer, Ulrich; Tokio, Fukahori; Makoto, Ishikawa; Osamu, Iwamoto; Chikara, Konno; Teruhiko, Kugo; Kenji, Nishihara; Tatsuhiko, Sato; Kenya, Suyama; Kenji, Yokoyama; Haeck, Wim; Hawari, Ayman; Holmes, Jessie; Jacqmin, Robert; Noguere, Gilles; Kodeli, Ivo; Koningy, Arjan; Lee, Morgan; Sublet, Jean-Christophe; Lubitz, Cecil; Romano, Paul; Millsy, Robert; Roubtsovy, Danila; Scopatz, Anthony; Sinitsa, Valentin; Soppera, Nicolas; Vogty, Romona

2015-01-01

This document attempts to compile the requirements for the top-levels of a hierarchical arrangement of nuclear data such as is found in the ENDF format. This set of requirements will be used to guide the development of a new set of formats to replace the legacy ENDF format. (authors)

Modeling of tethered satellite formations using graph theory

DEFF Research Database (Denmark)

Larsen, Martin Birkelund; Smith, Roy S; Blanke, Mogens

2011-01-01

satellite formation and proposes a method to deduce the equations of motion for the attitude dynamics of the formation in a compact form. The use of graph theory and Lagrange mechanics together allows a broad class of formations to be described using the same framework. A method is stated for finding...

Probes of Cosmic Star Formation History

Indian Academy of Sciences (India)

I summarize X-ray diagnostic studies of cosmic star formation history in terms of evolutionary schemes for X-ray binary evolution in normal galaxies with evolving star formation. Deep X-ray imaging studies by Chandra and XMM-Newton are now beginning to constrain both the X-ray luminosity evolution of galaxies and the ...

Seroma formation after surgery for breast cancer

Directory of Open Access Journals (Sweden)

Ebrahimi Mandana

2004-12-01

Full Text Available Abstract Background Seroma formation is the most frequent postoperative complication after breast cancer surgery. We carried out a study to investigate the effect of various demographic, clinical and therapeutic variables on seroma formation. Patients and methods A retrospective cross sectional study of patients who underwent surgical therapy for breast cancer with either modified radical mastectomy (MRM or breast preservation (BP was carried out. The demographic data and clinical information were extracted from case records. Seroma formation was studied in relation to age, type of surgery, tumor size, nodal involvement, preoperative chemotherapy, surgical instrument (electrocautery or scalpel, use of pressure garment, and duration of drainage. The multiple logistic regression analysis was performed to estimate odds ratios. Results A total of 158 patients with breast cancer were studied. The mean age of the patients was 46.3 years (SD ± 11.9. Seventy-three percent underwent modified radical mastectomy and the remaining 27% received breast preservation surgery. Seroma occurred in 35% of patients. In multivariate logistic regression analysis an association of postoperative seroma formation was noted with modified radical mastectomy (OR = 2.83, 95% CI 1.01–7.90, P = 0.04. No other factor studied was found to significantly effect the seroma formation after breast cancer surgery. Conclusion The findings suggest that the type of surgery is a predicting factor for seroma formation in breast cancer patients.

Method of treating non-supporting underground formations

International Nuclear Information System (INIS)

Anderson, B.W.; Trotty, K.D.

1977-01-01

Method of treating non-supporting underground formations, through which passes a borehole, aimed at preventing the transport of sand particles from the formation into the borehole during conveyance of liquids. (orig./RW) [de

Habit formation, work ethics, and technological progress

OpenAIRE

Faria, João Ricardo; León-Ledesma, Miguel A.

2002-01-01

Work ethics affects labor supply. This idea is modeled assuming that work is habit forming. This paper introduces working habits in a neoclassical growth model and compares its outcomes with a model without habit formation. In addition, it analyzes the impact of different forms of technical progress. The findings are that i) labor supply in the habit formation case is higher than in the neoclassical case; ii) unlike in the neoclassical case, labor supply in the presence of habit formation wil...

Negative ion formation and neutralization processes, (1)

International Nuclear Information System (INIS)

Sugiura, Toshio

1982-01-01

This review has been made preliminary for the purpose of contribute to the plasma heating by ''negative ion based neutral beam injection'' in the magnetic confinement fusion reactor. A compilation includes the survey of the general processes of negative ion formation, the data of the cross section of H - ion formation and the neutralization of H - ion, and some of new processes of H - ion formation. The data of cross section are mainly experimental, but partly include the results of theoretical calculation. (author)

Specific plant induced biofilm formation in Methylobacterium species

Science.gov (United States)

Rossetto, Priscilla B.; Dourado, Manuella N.; Quecine, Maria C.; Andreote, Fernando D.; Araújo, Welington L.; Azevedo, João L.; Pizzirani-Kleiner, Aline A.

2011-01-01

Two endophytic strains of Methylobacterium spp. were used to evaluate biofilm formation on sugarcane roots and on inert wooden sticks. Results show that biofilm formation is variable and that plant surface and possibly root exudates have a role in Methylobacterium spp. host recognition, biofilm formation and successful colonization as endophytes. PMID:24031703

Cosmic strings and galaxy formation

International Nuclear Information System (INIS)

Bertschinger, E.

1989-01-01

Cosmic strings have become increasingly popular candidates as seeds for the formation of structure in the universe. This scenario, remains a serious cosmogonical model despite close scrutiny. In constrast, magnetic monopoles and domain walls - relic topological defects as are cosmic strings - are disastrous for cosmology if they are left over from the early universe. The production of heavy cosmic strings is speculative, as it depends on the details of ultrahigh energy physics. Fortunately, speculation about cosmic strings is not entirely idle because, if they exist and are heavy enough to seed galaxy formation, cosmic strings can be detected astronomically. Failure to detect cosmic strings would impose some constraints on grand unified theories (GUTs); their discovery would have exciting consequences for high energy physics and cosmology. This article reviews the basic physics of nonsuperconducting cosmic strings, highlighting the field theory aspects, and provides a progress report on calculations of structure formation with cosmic strings

Unit Monitors Manchester-Format Data Buses

Science.gov (United States)

Amador, Jose J.

1994-01-01

Circuit card converts data signals into convenient hexadecimal form for troubleshooting. Bus-monitoring unit converts data signals from Manchester II format used on data bus into hexadecimal format. Monitoring circuit causes hexadecimal words to display on video terminal, where test engineer compares them with hexadecimal records for troubleshooting. Circuit monitors one bus or two buses simultaneously.

25 CFR 82.6 - Petition format.

Science.gov (United States)

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Petition format. 82.6 Section 82.6 Indians BUREAU OF... REORGANIZED UNDER FEDERAL STATUTE AND OTHER ORGANIZED TRIBES § 82.6 Petition format. Petitions may consist of... of a petition must set forth at least a summary of the objectives of the petitioners and must show...

Triggered star formation

Czech Academy of Sciences Publication Activity Database

Palouš, Jan; Ehlerová, Soňa

2002-01-01

Roč. 12, - (2002), s. 35-36 ISSN 1405-2059 R&D Projects: GA AV ČR IAA3003705; GA AV ČR KSK1048102 Institutional research plan: CEZ:AV0Z1003909 Keywords : interstellar medium * star formation * HI shells Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

Microbial processes in banded iron formation deposition

DEFF Research Database (Denmark)

Posth, Nicole; Konhauser, Kurt; Kappler, Andreas

2013-01-01

, remains unresolved. Evidence of an anoxic Earth with only localized oxic areas until the Great Oxidation Event ca 2·45 to 2·32 Ga makes the investigation of O2-independent mechanisms for banded iron formation deposition relevant. Recent studies have explored the long-standing proposition that Archean......Banded iron formations have been studied for decades, particularly regarding their potential as archives of the Precambrian environment. In spite of this effort, the mechanism of their deposition and, specifically, the role that microbes played in the precipitation of banded iron formation minerals...... banded iron formations may have been formed, and diagenetically modified, by anaerobic microbial metabolisms. These efforts encompass a wide array of approaches including isotope, ecophysiological and phylogeny studies, molecular and mineral marker analysis, and sedimentological reconstructions. Herein...

Gravitational instability, evolution of galaxies and star formation

International Nuclear Information System (INIS)

Palous, J.

1979-01-01

The gravitational collapse is the key to the theories of galaxy and star formation. The observations, showing intrinsic differences between elliptical and spiral galaxies, guide our fundamental conceptions on the formation and evolution of systems in question. Stars in elliptical galaxies and in spherical components of spiral galaxies were formed in a short period of time during early phases of protogalactic collapse, at a time of violent star formation. The disc-like components of spiral galaxies, however, were built gradually in the course of galactic evolution. Star formation in elliptical galaxies is described by the collision model of interstellar clouds, while star formation in discs is characterised by several processes: the expansion of HII regions, the expansion of supernovae remnants and the shock wave related to the presence of the spiral structure. (author)

Seminary Formation: A Case Study from the Pontifical Beda College, Rome

Science.gov (United States)

Strange, Roderick

2015-01-01

This case study account reviews issues related to seminary formation and education at the Beda College, Rome, including Fundamentals of Formation, Community Life, Organizing Formation, Intellectual Formation, Spiritual Formation, Pastoral Formation, and the challenges arising in these fields.

Program X4TOC4 (Version 86-1). Translation of experimental data from the EXFOR format to a computation format

International Nuclear Information System (INIS)

Cullen, D.E.

1986-09-01

Experimental nuclear reaction data are world-wide compiled in EXFOR format. The computer program X4TOC4 described in the present document translates data from the rather flexible EXFOR format to the more rigid ''computation format'' which is suitable for input to further computer processing of the data including graphical plotting. The program is available costfree from the IAEA Nuclear Data Section, upon request. (author)

Creating and maintaining a gas cap in tar sands formations

Science.gov (United States)

Vinegar, Harold J.; Karanikas, John Michael; Dinkoruk, Deniz Sumnu; Wellington, Scott Lee

2010-03-16

Methods for treating a tar sands formation are disclosed herein. Methods for treating a tar sands formation may include providing heat to at least part of a hydrocarbon layer in the formation from one or more heaters located in the formation. Pressure may be allowed to increase in an upper portion of the formation to provide a gas cap in the upper portion. At least some hydrocarbons are produced from a lower portion of the formation.

Dust formation and ionization in novae

International Nuclear Information System (INIS)

Yamamoto, Tetsuo; Sato, Shuji; Nariai, Kyoji.

1979-01-01

In order to explain the fact that some novae show the increase of infrared radiation indicating the formation of circumstellar dust grains while some others do not, the theory that the formation of dust in the circumstellar envelope of a nova depends on the intensity of ultraviolet radiation from a central star has been presented. It is known that the central star of a nova emits radiation at nearly constant rate, and its effective temperature rises. It was concluded that the novae with higher emission than a certain value are the poor candidates for dust formation because the whole envelope is ionized before dust is formed. But this conclusion is misleading. The evolution of the ultraviolet radiation emanating from a central star is summarized. The condensation of grains is possible when the partial pressure of the vapor, from which the grains are formed, becomes higher than the saturation vapor pressure. The temperature of grains can be estimated by equating the radiations absorbed and emitted. The grains evaporate if the grain temperature is higher than the condensation temperature. The formation of a Stroemgren sphere in the exploding envelope of a nova is discussed. For the formation of grains, it is necessary that temperature drops below the condensation temperature before the whole envelope is ionized. Hence dust grains do not grow if the grain temperature at a phase is higher than the condensation temperature. (Kako, I.)

The formation of stellar black holes

Science.gov (United States)

Mirabel, Félix

2017-08-01

It is believed that stellar black holes (BHs) can be formed in two different ways: Either a massive star collapses directly into a BH without a supernova (SN) explosion, or an explosion occurs in a proto-neutron star, but the energy is too low to completely unbind the stellar envelope, and a large fraction of it falls back onto the short-lived neutron star (NS), leading to the delayed formation of a BH. Theoretical models set progenitor masses for BH formation by implosion, namely, by complete or almost complete collapse, but observational evidences have been elusive. Here are reviewed the observational insights on BHs formed by implosion without large natal kicks from: (1) the kinematics in three dimensions of space of five Galactic BH X-ray binaries (BH-XRBs), (2) the diversity of optical and infrared observations of massive stars that collapse in the dark, with no luminous SN explosions, possibly leading to the formation of BHs, and (3) the sources of gravitational waves (GWs) produced by mergers of stellar BHs so far detected with LIGO. Multiple indications of BH formation without ejection of a significant amount of matter and with no natal kicks obtained from these different areas of observational astrophysics, and the recent observational confirmation of the expected dependence of BH formation on metallicity and redshift, are qualitatively consistent with the high merger rates of binary black holes (BBHs) inferred from the first detections with LIGO.

Endogenous leukotriene formation during anaphylactic shock

International Nuclear Information System (INIS)

Keppler, A.; Oerning, L.; Bernstroem, K.; Hammarstroem, S.

1987-01-01

Leukotriene (LT)C 4 is a biologically active substance, presumed to play major roles as a mediator of allergic and anaphylactic reactions. It is formed e.g. by basophilic and eosinophilic leukocytes, monocytes, macrophages, and mast cells. In cells having IgE receptors, bridging of these by divalent anti-IgE-receptor antibodies or by interaction between receptor-bound IgE and anti-IgE will induce LTC 4 formation. Leukotriene formation has also been demonstrated in other in vitro models of immediate hypersensivity. The biological actions of LTC 4 , comprise induction of airway obstruction, constriction of coronary arteries, hypotension, and plasma extravasation. Leukotriene formation in vivo may mediate anaphylactic shock symptoms and cause the death of an animal. In order to prove the presumed mediator role of this substance in anaphylactic reactions, it is necessary to demonstrate its endogenous formation during shock. Studies on the metabolism of LTC 4 have revealed rapid catabolism by various transformations of the peptide substituent. Recently, three metabolites were demonstrated to be excreted as end-products in man (LTE 4 ,) and the rat (N-acetyl LTE 4 and N-acetyl 11-trans LTE 4 ). By monitoring biliary N-acetyl LTE 4 levels, endogenous leukotriene formation in the rat was demonstrated in vivo after tissue trauma and endotoxin shock. We now wish to report evidence for endogenous leukotriene C 4 production during anaphylactic shock in guinea pigs. 37 refs. (author)

Pattern formations and oscillatory phenomena

CERN Document Server

Kinoshita, Shuichi

2013-01-01

Patterns and their formations appear throughout nature, and are studied to analyze different problems in science and make predictions across a wide range of disciplines including biology, physics, mathematics, chemistry, material science, and nanoscience. With the emergence of nanoscience and the ability for researchers and scientists to study living systems at the biological level, pattern formation research has become even more essential. This book is an accessible first of its kind guide for scientists, researchers, engineers, and students who require a general introduction to thi

The formation of ice sails

Science.gov (United States)

Fowler, A. C.; Mayer, C.

2017-11-01

Debris-covered glaciers are prone to the formation of a number of supraglacial geomorphological features, and generally speaking, their upper surfaces are far from level surfaces. Some of these features are due to radiation screening or enhancing properties of the debris cover, but theoretical explanations of the consequent surface forms are in their infancy. In this paper we consider a theoretical model for the formation of "ice sails", which are regularly spaced bare ice features which are found on debris-covered glaciers in the Karakoram.

A multiple-well method for immunohistochemical testing of many reagents on a single microscopic slide.

Science.gov (United States)

McKeever, P E; Letica, L H; Shakui, P; Averill, D R

1988-09-01

Multiple wells (M-wells) have been made over tissue sections on single microscopic slides to simultaneously localize binding specificity of many antibodies. More than 20 individual 4-microliter wells over tissue have been applied/slide, representing more than a 5-fold improvement in wells/slide and a 25-fold reduction in reagent volume over previous methods. More than 30 wells/slide have been applied over cellular monolayers. To produce the improvement, previous strategies of placing specimens into wells were changed to instead create wells over the specimen. We took advantage of the hydrophobic properties of paint to surround the wells and to segregate the various different primary antibodies. Segregation was complete on wells alternating with and without primary monoclonal antibody. The procedure accommodates both frozen and paraffin sections, yielding slides which last more than a year. After monoclonal antibody detection, standard histologic stains can be applied as counterstains. M-wells are suitable for localizing binding of multiple reagents or sample unknowns (polyclonal or monoclonal antibodies, hybridoma supernatants, body fluids, lectins) to either tissues or cells. Their small sample volume and large number of sample wells/slide could be particularly useful for early screening of hybridoma supernatants and for titration curves in immunohistochemistry (McKeever PE, Shakui P, Letica LH, Averill DR: J Histochem Cytochem 36:931, 1988).

Production, purification, crystallization and preliminary X-ray diffraction analysis of the HIV-2-neutralizing V3 loop-specific Fab fragment 7C8

International Nuclear Information System (INIS)

Uchtenhagen, Hannes; Sourial, Samer; Friemann, Rosmarie; Ehnlund, Mariethe; Spetz, Anna-Lena; Harris, Robert A.; Madhurantakam, Chaithanya; Achour, Adnane

2009-01-01

Neutralizing Fab fragments of the HIV-2-binding murine antibody 7C8 were generated after purification from hybridoma cell-culture supernatant. Crystallization conditions were determined and diffraction data were collected to 2.7 Å resolution. 7C8 is a mouse monoclonal antibody that is specific for the third hypervariable loop (V3 loop) of the human immunodeficiency virus type 2 (HIV-2) associated protein gp125. Fab fragments of 7C8 effectively neutralize HIV-2. 7C8 was expressed and purified from a hybridoma cell line in order to establish the molecular basis underlying the specificity of the 7C8 antibody for the V3 loop as well as the specific role of the elongated third complementarity-determining region of the heavy chain (CDRH3). The antibody was digested with papain and Fab fragments were purified using size-exclusion chromatography. Hanging-drop vapour-diffusion crystallization techniques were employed and the protein was crystallized in 50 mM ammonium sulfate, 100 mM Tris–HCl pH 8.5, 25%(w/v) PEG 8000 and 2.5%(w/v) PEG 400 at 275 K. The analysed crystals belonged to the rhombohedral space group P3 2 21, with unit-cell parameters a = b = 100.1, c = 196.8 Å, and diffracted to 2.7 Å resolution

Mass-Production and Characterization of Anti-CD20 Monoclonal Antibody in Peritoneum of Balb/c Mice

Directory of Open Access Journals (Sweden)

Leili Aghebati

2013-02-01

Full Text Available Purpose: Monoclonal antibodies are important tools are used in basic research as well as, in diagnosis, imaging and treatment of immunodeficiency diseases, infections and cancers. The purpose of this study was to produce large scale of monoclonal antibody against CD20 in order to diagnostic application in leukemia and lymphomas disorders. Methods: Hybridoma cells that produce monoclonal antibody against human CD20 were administered into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. After twelve days, approximately 7 ml ascetic fluid was harvested from the peritoneum of each mouse. Evaluation of mAb titration was assessed by ELISA method. In the present study, we describe a protocol for large scale production of MAbs. Results: We prepared monoclonal antibodies (mAbs with high specificity and sensitivity against human CD20 by hybridoma method and characterized them by ELISA. The subclass of antibody was IgG2a and its light chain was kappa. Ascetic fluid was purified by Protein-A Sepharose affinity chromatography and the purified monoclonal antibody was conjugated with FITC and Immunofluorescence was done for confirming the specific binding. Conclusion: The conjugated monoclonal antibody could have application in diagnosis B-cell lymphomas, hairy cell leukemia, B-cell chronic lymphocytic leukemia, and melanoma cancer stem cells.

Large Scale Generation and Characterization of Anti-Human IgA Monoclonal Antibody in Ascitic Fluid of Balb/c Mice

Science.gov (United States)

Ezzatifar, Fatemeh; Majidi, Jafar; Baradaran, Behzad; Aghebati Maleki, Leili; Abdolalizadeh, Jalal; Yousefi, Mehdi

2015-01-01

Purpose: Monoclonal antibodies are potentially powerful tools used in biomedical research, diagnosis, and treatment of infectious diseases and cancers. The monoclonal antibody against Human IgA can be used as a diagnostic application to detect infectious diseases. The aim of this study was to improve an appropriate protocol for large-scale production of mAbs against IgA. Methods: For large-scale production of the monoclonal antibody, hybridoma cells that produce monoclonal antibodies against Human IgA were injected intraperitoneally into Balb/c mice that were previously primed with 0.5 ml Pristane. After ten days, ascitic fluid was harvested from the peritoneum of each mouse. The ELISA method was carried out for evaluation of the titration of produced mAbs. The ascitic fluid was investigated in terms of class and subclass by a mouse mAb isotyping kit. MAb was purified from the ascitic fluid by ion exchange chromatography. The purity of the monoclonal antibody was confirmed by SDS-PAGE, and the purified monoclonal antibody was conjugated with HRP. Results: Monoclonal antibodies with high specificity and sensitivity against Human IgA were prepared by hybridoma technology. The subclass of antibody was IgG1 and its light chain was the kappa type. Conclusion: This conjugated monoclonal antibody could have applications in designing ELISA kits in order to diagnose different infectious diseases such as toxoplasmosis and H. Pylori. PMID:25789225

Mass-Production and Characterization of Anti-CD20 Monoclonal Antibody in Peritoneum of Balb/c Mice

Science.gov (United States)

Sineh sepehr, Koushan; Baradaran, Behzad; Majidi, Jafar; Abdolalizadeh, Jalal; Aghebati, leili; Zare Shahneh, Fatemeh

2013-01-01

Purpose: Monoclonal antibodies are important tools are used in basic research as well as, in diagnosis, imaging and treatment of immunodeficiency diseases, infections and cancers. The purpose of this study was to produce large scale of monoclonal antibody against CD20 in order to diagnostic application in leukemia and lymphomas disorders. Methods: Hybridoma cells that produce monoclonal antibody against human CD20 were administered into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. After twelve days, approximately 7 ml ascetic fluid was harvested from the peritoneum of each mouse. Evaluation of mAb titration was assessed by ELISA method. In the present study, we describe a protocol for large scale production of MAbs. Results: We prepared monoclonal antibodies (mAbs) with high specificity and sensitivity against human CD20 by hybridoma method and characterized them by ELISA. The subclass of antibody was IgG2a and its light chain was kappa. Ascetic fluid was purified by Protein-A Sepharose affinity chromatography and the purified monoclonal antibody was conjugated with FITC and Immunofluorescence was done for confirming the specific binding. Conclusion: The conjugated monoclonal antibody could have application in diagnosis B-cell lymphomas, hairy cell leukemia, B-cell chronic lymphocytic leukemia, and melanoma cancer stem cells. PMID:24312821

Large Scale Generation and Characterization of Anti-Human IgA Monoclonal Antibody in Ascitic Fluid of Balb/c Mice

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Fatemeh Ezzatifar

2015-03-01

Full Text Available Purpose: Monoclonal antibodies are potentially powerful tools used in biomedical research, diagnosis, and treatment of infectious diseases and cancers. The monoclonal antibody against Human IgA can be used as a diagnostic application to detect infectious diseases. The aim of this study was to improve an appropriate protocol for large-scale production of mAbs against IgA. Methods: For large-scale production of the monoclonal antibody, hybridoma cells that produce monoclonal antibodies against Human IgA were injected intraperitoneally into Balb/c mice that were previously primed with 0.5 ml Pristane. After ten days, ascitic fluid was harvested from the peritoneum of each mouse. The ELISA method was carried out for evaluation of the titration of produced mAbs. The ascitic fluid was investigated in terms of class and subclass by a mouse mAb isotyping kit. MAb was purified from the ascitic fluid by ion exchange chromatography. The purity of the monoclonal antibody was confirmed by SDS-PAGE, and the purified monoclonal antibody was conjugated with HRP. Results: Monoclonal antibodies with high specificity and sensitivity against Human IgA were prepared by hybridoma technology. The subclass of antibody was IgG1 and its light chain was the kappa type. Conclusion: This conjugated monoclonal antibody could have applications in designing ELISA kits in order to diagnose different infectious diseases such as toxoplasmosis and H. Pylori.

Generation and Application of Monoclonal Antibody Against Lycopene.

Science.gov (United States)

Tsibezov, Valeriy V; Bashmakov, Yuriy K; Pristenskiy, Dmitry V; Zigangirova, Naylia A; Kostina, Ludmila V; Chalyk, Natalya E; Kozlov, Alexey Y; Morgunova, Elena Y; Chernyshova, Marina P; Lozbiakova, Marina V; Kyle, Nigel H; Petyaev, Ivan M

2017-04-01

A monoclonal antibody (Mab) against lycopene was developed from hybridoma clones obtained from BALB/c mice immunized with trans-isomer of lycopene (t-lycopene, t-LC) conjugated with colloidal gold particles. An alternating immunization schedule which included injection of both formulations of immunogen (without and with Freund's adjuvant) was most effective in the elucidation of a measurable immune response to the t-Lycopene conjugate. Selected hybridoma clones were able to produce an Mab positive in competition assay. In particular, preincubation of 6B9 Mabs with t-LC abolished the ability of 6B9 Mabs to bind LC in the competition assay. Mabs produced by other clones (4F10, 4A3, and 3B12) worked similarly. Analysis of antigen specificity showed that 6B9 Mab raised against t-LC did not recognize other carotenoids such as lutein and carotene. Mab 6B9 was shown to recognize lycopene on a glass surface and in the settings of indirect immunofluorescence experiments performed in cultured hepatocytes and alveolar macrophages incubated with and without lycopene, as well as in sebum and corneocyte specimens from the skin of volunteers supplemented with nutraceutical formulation of lycopene. Newly generated Mabs against lycopene may provide a valuable tool for different analytical assays of lycopene content in various biological, agricultural, and food products.

Characterization of antigen association with accessory cells: specific removal of processed antigens from the cell surface by phospholipases

International Nuclear Information System (INIS)

Falo, L.D. Jr.; Haber, S.I.; Herrmann, S.; Benacerraf, B.; Rock, K.L.

1987-01-01

To characterize the basis for the cell surface association of processed antigen with the antigen-presenting cell (APC) the authors analyzed its sensitivity to enzymatic digestion. Antigen-exposed APC that are treated with phospholipase and then immediately fixed lose their ability to stimulate antigen-plus-Ia-specific T-T hybridomas. This effect is seen with highly purified phospholipase A 2 and phospholipase C. In addition it is observed with three distinct antigens - ovalbumin, bovine insulin, and poly(LGlu 56 LLys 35 LPhe 9 )[(GluLysPhe)/sub n/]. The effect of phospholipases is highly specific. Identically treated APC are equivalent to control in their ability to stimulate alloreactive hybridomas specific for precisely the same Ia molecule that is corecognized by antigen-plus-Ia-specific hybrids. Furthermore, the antigen-presenting function of enzyme-treated, fixed APC can be reconstituted by the addition of exogenous in vitro processed or processing independent antigens. In parallel studies 125 I-labeled avidin was shown to specifically bind to APC that were previously exposed and allowed to process biotin-insulin. Biotin-insulin-exposed APC that are pretreated with phospholipase bind significantly less 125 I-labeled avidin than do untreated, exposed APC. Identical enzyme treatment does not reduce the binding of avidin to a biotinylated antibody already bound to class II major histocompatibility complex molecules of APC. These studies demonstrate that phospholipase effectively removes processed cell surface antigen

Nitrate formation during ozonation as a surrogate parameter for abatement of micropollutants and the N-nitrosodimethylamine (NDMA) formation potential.

Science.gov (United States)

Song, Yang; Breider, Florian; Ma, Jun; von Gunten, Urs

2017-10-01

In this study, nitrate formation from ammonium and/or dissolved organic nitrogen (DON) was investigated as a novel surrogate parameter to evaluate the abatement of micropollutants during ozonation of synthetic waters containing natural organic matter (NOM) isolates, a natural water and secondary wastewater effluents. Nitrate formation during ozonation was compared to the changes in UV absorbance at 254 nm (UVA 254 ) including the effect of pH. For low specific ozone doses UVA 254 was abated more efficiently than nitrate was formed. This is due to a relatively slow rate-limiting step for nitrate formation from the reaction between ozone and a proposed nitrogen-containing intermediate. This reaction cannot compete with the fast reactions between ozone and UV-absorbing moieties (e.g., activated aromatic compounds). To further test the kinetics of nitrate formation, two possible intermediates formed during ozonation of DON were tested. At pH 7, nitrate was formed during ozonation of acetone oxime and methyl nitroacetate with second-order rate constants of 256.7 ± 4.7 M -1  s -1 and 149.5 ± 5.8 M -1  s -1 , respectively. The abatement of the selected micropollutants (i.e., 17α-ethinylestradiol (EE2), carbamazepine (CBZ), bezafibrate (BZF), ibuprofen (IBU), and p-chlorobenzoic acid (pCBA)) was investigated for specific ozone doses ≤1.53 mgO 3 /mgDOC and its efficiency depended strongly on the reactivity of the selected compounds with ozone. The relative abatement of micropollutants (i.e., EE2 and CBZ) with high ozone reactivity showed linear relationships with nitrate formation. The abatement of micropollutants with intermediate-low ozone reactivity (BZF, IBU, and pCBA) followed one- and two-phase behaviors relative to nitrate formation during ozonation of water samples containing high and low concentrations of nitrate-forming DON, respectively. During ozonation of a wastewater sample, the N-nitrosodimethylamine formation potential (NDMA-FP) during

THE PSYCHOLOGICAL PECULIARITIES OF THE INFORMATION-COMMUNICATION COMPETENCE FORMATION

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Pyannikov Mikhail Mikhailovich

2013-01-01

Full Text Available Informatization of society has significantly changed the paradigm of education, posing the new problems to the scientists. One of such problems is the formation of new conscience – conscience, whose inalienable part is the information culture. The information-communication competence is the basis for the formation of such conscience. In this connection the aim of study is the analysis of psychological peculiarities of the formation of information-communication competence and determination of the role of this personality new formation in conscience of a modern human. The characteristic features of psychological new formations, the stages of cultural development and the role of cultural level of society in the formation of world outlook of a child are studied in this work. In the result of study there was found out the basis of psychic development. The sphere of results application includes the conclusions received in the result of study, which can be used by scholars, who deal with the problem of psychic development of a child. In practice the data of study help to understand better the stages of skill formation and the role of elementary actions in the formation of complex behavioral system.

Relative dynamics and motion control of nanosatellite formation flying

Science.gov (United States)

Pimnoo, Ammarin; Hiraki, Koju

2016-04-01

Orbit selection is a necessary factor in nanosatellite formation mission design/meanwhile, to keep the formation, it is necessary to consume fuel. Therefore, the best orbit design for nanosatellite formation flying should be one that requires the minimum fuel consumption. The purpose of this paper is to analyse orbit selection with respect to the minimum fuel consumption, to provide a convenient way to estimate the fuel consumption for keeping nanosatellite formation flying and to present a simplified method of formation control. The formation structure is disturbed by J2 gravitational perturbation and other perturbing accelerations such as atmospheric drag. First, Gauss' Variation Equations (GVE) are used to estimate the essential ΔV due to the J2 perturbation and atmospheric drag. The essential ΔV presents information on which orbit is good with respect to the minimum fuel consumption. Then, the linear equations which account for J2 gravitational perturbation of Schweighart-Sedwick are presented and used to estimate the fuel consumption to maintain the formation structure. Finally, the relative dynamics motion is presented as well as a simplified motion control of formation structure by using GVE.

Flexible Structure Control Scheme of a UAVs Formation to Improve the Formation Stability During Maneuvers

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Kownacki Cezary

2017-09-01

Full Text Available One of the issues related to formation flights, which requires to be still discussed, is the stability of formation flight in turns, where the aerodynamic conditions can be substantially different for outer vehicles due to varying bank angles. Therefore, this paper proposes a decentralized control algorithm based on a leader as the reference point for followers, i.e. other UAVs and two flocking behaviors responsible for local position control, i.e. cohesion and repulsion. But opposite to other research in this area, the structure of the formation becomes flexible (structure is being reshaped and bent according to actual turn radius of the leader. During turns the structure is bent basing on concentred circles with different radiuses corresponding to relative locations of vehicles in the structure. Simultaneously, UAVs' air-speeds must be modified according to the length of turn radius to achieve the stability of the structure. The effectiveness of the algorithm is verified by the results of simulated flights of five UAVs.

ALPINE MAGMATIC-METALLOGENIC FORMATIONS OF THE NORTHWESTERN AND CENTRAL DINARIDES

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Jakob Pamić

1997-12-01

Full Text Available In the paper are presented basic geological, petrologieca1, geochemi-cal and mineral deposit data for five main magmatic-metallogenic formations of the northwestern and central Dinarides: (lThe Permo Triassic rifting related andesite-diorite formations; (2 The Jurassic-Lower Cretaceous accretionary (ophiolite formations; (3 The Upper Cretaceous-Paleogene subduction related basalt-rhyohite formations; (4 The Paleogene collisional granite formations, and (5 The Oligo-cene-Neogene postsubduction andesite formations. All these magmatic-metallogenic formations originated in different geotectonic settings during the Alpine evolution of the Dinaridic parts of thc Tethys and the postorogenic evolution of the Paratethys and the Pannonian Basin, respectively.

Thermodynamics and kinetics of vesicles formation processes.

Science.gov (United States)

Guida, Vincenzo

2010-12-15

Vesicles are hollow aggregates, composed of bilayers of amphiphilic molecules, dispersed into and filled with a liquid solvent. These aggregates can be formed either as equilibrium or as out of equilibrium meta-stable structures and they exhibit a rich variety of different morphologies. The surprising richness of structures, the vast range of industrial applications and the presence of vesicles in a number of biological systems have attracted the interest of numerous researchers and scientists. In this article, we review both the thermodynamics and the kinetics aspects of the phenomena of formation of vesicles. We start presenting the thermodynamics of bilayer membranes formation and deformation, with the aim of deriving the conditions for the existence of equilibrium vesicles. Specifically, we use the results from continuum thermodynamics to discuss the possibility of formation of stable equilibrium vesicles, from both mixed amphiphiles and single component systems. We also link the bilayer membrane properties to the molecular structure of the starting amphiphiles. In the second part of this article, we focus on the dynamics and kinetics of vesiculation. We review the process of vesicles formation both from planar lamellar phase under shear and from isotropic micelles. In order to clarify the physical mechanisms of vesicles formation, we continuously draw a parallel between emulsification and vesiculation processes. Specifically, we compare the experimental results, the driving forces and the relative scaling laws identified for the two processes. Describing the dynamics of vesicles formation, we also discuss why non equilibrium vesicles can be formed by kinetics control and why they are meta-stable. Understanding how to control the properties, the stability and the formation process of vesicles is of fundamental importance for a vast number of industrial applications. Copyright © 2009. Published by Elsevier B.V.

Object formation and subject formation: The innovation campus in the Netherlands

NARCIS (Netherlands)

Kooij, H.J.

2015-01-01

A central question within planning theory is how changes between the relations of ‘grand institutions’ such as state, market and education influence the formation of objects ‘on the ground’. Drawing upon Foucault’s work, this article contributes to the understanding of these relations and argues

The early ISM and galaxy formation

Science.gov (United States)

White, Simon D. M.

1990-01-01

Current ideas about galaxy formation are reviewed, with particular attention to when and how it occurred, and what it might have looked like. It is argued that galaxy formation is more recent than originally predicted. Suggestions are presented as to how current observations of distant objects may be interpreted within the cold dark matter theory for the origin of structure.

Atmospheric particle formation in spatially and temporally varying conditions

Energy Technology Data Exchange (ETDEWEB)

Lauros, J.

2011-07-01

Atmospheric particles affect the radiation balance of the Earth and thus the climate. New particle formation from nucleation has been observed in diverse atmospheric conditions but the actual formation path is still unknown. The prevailing conditions can be exploited to evaluate proposed formation mechanisms. This study aims to improve our understanding of new particle formation from the view of atmospheric conditions. The role of atmospheric conditions on particle formation was studied by atmospheric measurements, theoretical model simulations and simulations based on observations. Two separate column models were further developed for aerosol and chemical simulations. Model simulations allowed us to expand the study from local conditions to varying conditions in the atmospheric boundary layer, while the long-term measurements described especially characteristic mean conditions associated with new particle formation. The observations show statistically significant difference in meteorological and back-ground aerosol conditions between observed event and non-event days. New particle formation above boreal forest is associated with strong convective activity, low humidity and low condensation sink. The probability of a particle formation event is predicted by an equation formulated for upper boundary layer conditions. The model simulations call into question if kinetic sulphuric acid induced nucleation is the primary particle formation mechanism in the presence of organic vapours. Simultaneously the simulations show that ignoring spatial and temporal variation in new particle formation studies may lead to faulty conclusions. On the other hand, the theoretical simulations indicate that short-scale variations in temperature and humidity unlikely have a significant effect on mean binary water sulphuric acid nucleation rate. The study emphasizes the significance of mixing and fluxes in particle formation studies, especially in the atmospheric boundary layer. The further

Negative ion formation processes: A general review

International Nuclear Information System (INIS)

Alton, G.D.

1990-01-01

The principal negative ion formation processes will be briefly reviewed. Primary emphasis will be placed on the more efficient and universal processes of charge transfer and secondary ion formation through non-thermodynamic surface ionization. 86 refs., 20 figs

Protostar formation in the early universe.

Science.gov (United States)

Yoshida, Naoki; Omukai, Kazuyuki; Hernquist, Lars

2008-08-01

The nature of the first generation of stars in the universe remains largely unknown. Observations imply the existence of massive primordial stars early in the history of the universe, and the standard theory for the growth of cosmic structure predicts that structures grow hierarchically through gravitational instability. We have developed an ab initio computer simulation of the formation of primordial stars that follows the relevant atomic and molecular processes in a primordial gas in an expanding universe. The results show that primeval density fluctuations left over from the Big Bang can drive the formation of a tiny protostar with a mass 1% that of the Sun. The protostar is a seed for the subsequent formation of a massive primordial star.

Microwave based method of monitoring crack formation

International Nuclear Information System (INIS)

Aman, Sergej; Aman, Alexander; Majcherek, Soeren; Hirsch, Soeren; Schmidt, Bertram

2014-01-01

The formation of cracks in glass particles was monitored by application of linearly polarized microwaves. The breakage behavior of glass spheres coated with a thin gold layer of about 50 nm, i.e. a thickness that is lower than the microwave penetration depth, was tested. In this way the investigation of fracture behavior of electronic circuits was simulated. A shielding current was induced in the gold layer by the application of microwaves. During the crack formation the distribution of this current changed abruptly and a scattered microwave signal appeared at the frequency of the incident microwaves. The time behavior of the scattered signal reflects the microscopic processes occurring during the fracture of the specimen. The duration of the increasing signal corresponds to the crack formation time in the tested specimen. This time was estimated as particle size divided by crack development speed in glass. An intense emission of electrons occurs during the formation of cracks. Due to this, coherent Thomson scattering of microwaves by emitted electrons becomes significant with a delay of a few microseconds after the initial phase of crack formation. In this time the intensity of the microwave signal increases. (paper)

Galaxy formation: internal mechanisms and cosmological processes

International Nuclear Information System (INIS)

Martig, Marie

2010-01-01

This thesis is devoted to galaxy formation and evolution in a cosmological context. Cosmological simulations have unveiled two main modes of galaxy growth: hierarchical growth by mergers and accretion of cold gas from cosmic filaments. However, these simulations rarely take into account small scale mechanisms, that govern internal evolution and that are a key ingredient to understand galaxy formation and evolution. Thanks to a new simulation technique that I have developed, I first studied the colors of galaxies, and in particular the reddening of elliptical galaxies. I showed that the gas disk in an elliptical galaxy could be stabilized against star formation because of the galaxy's stellar component being within a spheroid instead of a disk. This mechanism can explain the red colors of some elliptical galaxies that contain a gas disk. I also studied the formation of spiral galaxies: most cosmological simulations cannot explain the formation of Milky Way-like galaxies, i.e. with a large disk and a small bulge. I showed that this issue could be partly solved by taking into account in the simulations the mass loss from evolved stars through stellar winds, planetary nebulae and supernovae explosions. (author) [fr

Star-formation history of very young clusters

International Nuclear Information System (INIS)

Stahler, S.W.

1985-01-01

The popular idea that star formation has proceeded sequentially from lowest to highest mass members in open clusters is examined critically. For extremely young clusters, such as NGC 2264 and NGC 6530, this sequential hypothesis is a consequence of the assignment of pre-main-sequence contraction ages to all member stars. However, such ages yield a formation history which is implausible from a physical point of view, since the critical time for the onset of formation at any stellar mass is equal to the pre-main-sequence contraction time for that mass. Moreover, these ages are in conflict with the strong observational evidence that a substantial fraction of cluster members have already reached the main sequence. After reconsideration of the probable main-sequence members, the stellar ages in NGC 2264 and NGC 6530 are consistent with a variety of formation histories, and, in particular, with the view that all stellar masses form in approximately the same interval of time within a given cluster, i.e., that there is no mass-age correlation. A notion closely related to the sequential hypothesis, that the total star-formation rate increases exponentially with time, is subject to the same criticism

The formation of planets by disc fragmentation

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Stamatellos Dimitris

2013-04-01

Full Text Available I discuss the role that disc fragmentation plays in the formation of gas giant and terrestrial planets, and how this relates to the formation of brown dwarfs and low-mass stars, and ultimately to the process of star formation. Protostellar discs may fragment, if they are massive enough and can cool fast enough, but most of the objects that form by fragmentation are brown dwarfs. It may be possible that planets also form, if the mass growth of a proto-fragment is stopped (e.g. if this fragment is ejected from the disc, or suppressed and even reversed (e.g by tidal stripping. I will discuss if it is possible to distinguish whether a planet has formed by disc fragmentation or core accretion, and mention of a few examples of observed exoplanets that are suggestive of formation by disc fragmentation.

Promoting proximal formative assessment with relational discourse

Science.gov (United States)

Scherr, Rachel E.; Close, Hunter G.; McKagan, Sarah B.

2012-02-01

The practice of proximal formative assessment - the continual, responsive attention to students' developing understanding as it is expressed in real time - depends on students' sharing their ideas with instructors and on teachers' attending to them. Rogerian psychology presents an account of the conditions under which proximal formative assessment may be promoted or inhibited: (1) Normal classroom conditions, characterized by evaluation and attention to learning targets, may present threats to students' sense of their own competence and value, causing them to conceal their ideas and reducing the potential for proximal formative assessment. (2) In contrast, discourse patterns characterized by positive anticipation and attention to learner ideas increase the potential for proximal formative assessment and promote self-directed learning. We present an analysis methodology based on these principles and demonstrate its utility for understanding episodes of university physics instruction.

Inflow of atomic gas fuelling star formation

DEFF Research Database (Denmark)

Michałowski, M. J.; Gentile, G.; Hjorth, Jeppe

2016-01-01

Gamma-ray burst host galaxies are deficient in molecular gas, and show anomalous metal-poor regions close to GRB positions. Using recent Australia Telescope Compact Array (ATCA) Hi observations we show that they have substantial atomic gas reservoirs. This suggests that star formation in these ga......Gamma-ray burst host galaxies are deficient in molecular gas, and show anomalous metal-poor regions close to GRB positions. Using recent Australia Telescope Compact Array (ATCA) Hi observations we show that they have substantial atomic gas reservoirs. This suggests that star formation...... in these galaxies may be fuelled by recent inflow of metal-poor atomic gas. While this process is debated, it can happen in low-metallicity gas near the onset of star formation because gas cooling (necessary for star formation) is faster than the Hi-to-H2 conversion....

Systematization of experiences in the professor formation to integrate the university and the family to the professional formation.

Directory of Open Access Journals (Sweden)

Geycell Emma Guevara Fernández

2012-04-01

Full Text Available The current work presents a systematization of experiences carried out at the University José Martí Pérez of Sancti Spíritus as a modality of participative action research which permitted, from the articulation of theory and practice, to organize the knowledge about family-university relationship and its influence in the professional formation. As a starting point, different diagnostic techniques were applied such as: document analysis, participating observation, auto assessing scales, discussion groups, interviews, survey and the methodological triangulation data which led to the determination of shortages and potentialities that the staff had as to formation to face it. By means of a shared process, the implied actors agreed the execution of actions which supplied the formative needs and led to grow up gradually towards the improvement of a continuing formation for the educative orientation carried out in higher education and where the development social situation of the young university professor demands as a fundamental category.

Distributed formation tracking using local coordinate systems

DEFF Research Database (Denmark)

Yang, Qingkai; Cao, Ming; Garcia de Marina, Hector

2018-01-01

This paper studies the formation tracking problem for multi-agent systems, for which a distributed estimator–controller scheme is designed relying only on the agents’ local coordinate systems such that the centroid of the controlled formation tracks a given trajectory. By introducing a gradient...... descent term into the estimator, the explicit knowledge of the bound of the agents’ speed is not necessary in contrast to existing works, and each agent is able to compute the centroid of the whole formation in finite time. Then, based on the centroid estimation, a distributed control algorithm...

Emissions and dioxins formation from waste incinerators

International Nuclear Information System (INIS)

Carbone, A.I.; Zagaroli, M.

1989-01-01

This paper describes current knowledge on dioxins formation and emission from waste incinerators. The pertinent Italian law and effects on man health are dealt with, too. The picture of existing municipal incinerators is presented concerning both the actual emission levels and the monitored levels in the environment. Sampling and analysis systems of these organic chlorinated micro-pollutants and current theories on precursors, formation mechanisms, and influence of different parameters are also described. The last section deals with some of the techniques that can be used to reduce dioxins formation and emission from municipal incinerators. (author)

Formation and filtration characteristics of solids generated in a high level liquid waste treatment process. Solids formation behavior from simulated high level liquid waste

International Nuclear Information System (INIS)

Kondo, Y.; Kubota, M.

1997-01-01

The solids formation behavior in a simulated high level liquid waste (HLLW) was experimentally examined, when the simulated HLLW was treated in the ordinary way of actual HLLW treatment process. Solids formation conditions and mechanism were closely discussed. The solids formation during a concentration step can be explained by considering the formation of zirconium phosphate, phosphomolybdic acid and precipitation of strontium and barium nitrates and their solubilities. For the solids formation during the denitration step, at least four courses were observed; formation of an undissolved material by a chemical reaction with each other of solute elements (zirconium, molybdenum, tellurium) precipitation by reduction (platinum group metals) formation of hydroxide or carbonate compounds (chromium, neodymium, iron, nickel, strontium, barium) and a physical adsorption to stable solid such as zirconium molybdate (nickel, strontium, barium). (author)

Plasma formation in TBR

International Nuclear Information System (INIS)

Del Bosco, E.

1981-01-01

In this work are presented and discussed results of the formation and equilibrium of the plasma current in TBR, a small tokamak, designed and contructed at the Instituto de Fisica of Universidade de Sao Paulo. The measured breakdown curves for H 2 , A and He are compared with the predictions of a simple model with reasonable agreement. The influence of stray magnetic fields in the plasma formation is investigated and conditions are chosen to facilitate the breakdown. The time profile of loop voltage and plasma current for shots with plasma equilibrium are shown. A comparison is made between experimental results and analytical-numerical model for tokamaks discharges with ohmic heating. Reasonable agreement is obtained when Z, effective atomic number, is assumed as a parameter. (Author) [pt

Reconsidering Formative Measurement

Science.gov (United States)

Howell, Roy D.; Breivik, Einar; Wilcox, James B.

2007-01-01

The relationship between observable responses and the latent constructs they are purported to measure has received considerable attention recently, with particular focus on what has become known as formative measurement. This alternative to reflective measurement in the area of theory-testing research is examined in the context of the potential…

Cu(II) promotes amyloid pore formation

International Nuclear Information System (INIS)

Zhang, Hangyu; Rochet, Jean-Christophe; Stanciu, Lia A.

2015-01-01

The aggregation of α-synuclein is associated with dopamine neuron death in Parkinson's disease. There is controversy in the field over the question of which species of the aggregates, fibrils or protofibrils, are toxic. Moreover, compelling evidence suggested the exposure to heavy metals to be a risk of PD. Nevertheless, the mechanism of metal ions in promoting PD remains unclear. In this research, we investigated the structural basis of Cu(II) induced aggregation of α-synuclein. Using transmission electron microscopy experiments, Cu(II) was found to promote in vitro aggregation of α-synuclein by facilitating annular protofibril formation rather than fibril formation. Furthermore, neuroprotective baicalein disaggregated annular protofibrils accompanied by considerable decrease of β-sheet content. These results strongly support the hypothesis that annular protofibrils are the toxic species, rather than fibrils, thereby inspiring us to search novel therapeutic strategies for the suppression of the toxic annular protofibril formation. - Highlights: • Cu(II) promoted the annular protofibril formation of α-synuclein in vitro. • Cu(II) postponed the in vitro fibrillization of α-synuclein. • Neuroprotective baicalein disaggregated annular protofibrils

Cu(II) promotes amyloid pore formation

Energy Technology Data Exchange (ETDEWEB)

Zhang, Hangyu, E-mail: hangyuz@uw.edu [Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907 (United States); Rochet, Jean-Christophe [Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907 (United States); Stanciu, Lia A. [Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907 (United States); School of Materials Engineering, Purdue University, West Lafayette, IN 47907 (United States)

2015-08-14

The aggregation of α-synuclein is associated with dopamine neuron death in Parkinson's disease. There is controversy in the field over the question of which species of the aggregates, fibrils or protofibrils, are toxic. Moreover, compelling evidence suggested the exposure to heavy metals to be a risk of PD. Nevertheless, the mechanism of metal ions in promoting PD remains unclear. In this research, we investigated the structural basis of Cu(II) induced aggregation of α-synuclein. Using transmission electron microscopy experiments, Cu(II) was found to promote in vitro aggregation of α-synuclein by facilitating annular protofibril formation rather than fibril formation. Furthermore, neuroprotective baicalein disaggregated annular protofibrils accompanied by considerable decrease of β-sheet content. These results strongly support the hypothesis that annular protofibrils are the toxic species, rather than fibrils, thereby inspiring us to search novel therapeutic strategies for the suppression of the toxic annular protofibril formation. - Highlights: • Cu(II) promoted the annular protofibril formation of α-synuclein in vitro. • Cu(II) postponed the in vitro fibrillization of α-synuclein. • Neuroprotective baicalein disaggregated annular protofibrils.

Transcriptional regulation of Drosophila gonad formation.

Science.gov (United States)

Tripathy, Ratna; Kunwar, Prabhat S; Sano, Hiroko; Renault, Andrew D

2014-08-15

The formation of the Drosophila embryonic gonad, involving the fusion of clusters of somatic gonadal precursor cells (SGPs) and their ensheathment of germ cells, provides a simple and genetically tractable model for the interplay between cells during organ formation. In a screen for mutants affecting gonad formation we identified a SGP cell autonomous role for Midline (Mid) and Longitudinals lacking (Lola). These transcriptional factors are required for multiple aspects of SGP behaviour including SGP cluster fusion, germ cell ensheathment and gonad compaction. The lola locus encodes more than 25 differentially spliced isoforms and we have identified an isoform specific requirement for lola in the gonad which is distinct from that in nervous system development. Mid and Lola work in parallel in gonad formation and surprisingly Mid overexpression in a lola background leads to additional SGPs at the expense of fat body cells. Our findings support the idea that although the transcription factors required by SGPs can ostensibly be assigned to those being required for either SGP specification or behaviour, they can also interact to impinge on both processes. Copyright © 2014 Elsevier Inc. All rights reserved.

TIME-VARYING DYNAMICAL STAR FORMATION RATE

Energy Technology Data Exchange (ETDEWEB)

Lee, Eve J.; Chang, Philip; Murray, Norman, E-mail: evelee@berkeley.edu [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, University of Toronto, Toronto, ON M5S 3H8 (Canada)

2015-02-10

We present numerical evidence of dynamic star formation in which the accreted stellar mass grows superlinearly with time, roughly as t {sup 2}. We perform simulations of star formation in self-gravitating hydrodynamic and magnetohydrodynamic turbulence that is continuously driven. By turning the self-gravity of the gas in the simulations on or off, we demonstrate that self-gravity is the dominant physical effect setting the mass accretion rate at early times before feedback effects take over, contrary to theories of turbulence-regulated star formation. We find that gravitational collapse steepens the density profile around stars, generating the power-law tail on what is otherwise a lognormal density probability distribution function. Furthermore, we find turbulent velocity profiles to flatten inside collapsing regions, altering the size-line width relation. This local flattening reflects enhancements of turbulent velocity on small scales, as verified by changes to the velocity power spectra. Our results indicate that gas self-gravity dynamically alters both density and velocity structures in clouds, giving rise to a time-varying star formation rate. We find that a substantial fraction of the gas that forms stars arrives via low-density flows, as opposed to accreting through high-density filaments.

Solution mining dawsonite from hydrocarbon containing formations with a chelating agent

Science.gov (United States)

Vinegar, Harold J [Bellaire, TX

2009-07-07

A method for treating an oil shale formation comprising dawsonite includes providing heat from one or more heaters to the formation to heat the formation. Hydrocarbon fluids are produced from the formation. At least some dawsonite in the formation is decomposed with the provided heat. A chelating agent is provided to the formation to dissolve at least some dawsonite decomposition products. The dissolved dawsonite decomposition products are produced from the formation.

Evaluation of anomalies during nickel and titanium silicide formation using the effective heat of formation mode

CSIR Research Space (South Africa)

Pretorius, R

1993-11-01

Full Text Available , as well as the observed sequence of growth of different silicide phases, are not in agree- ment with thermodynamic considerations [26]. In the case of the nickel silicides Ni,Si is nearly always found to be the first... to determine how the oxygen content in the silicon affects phase formation. We also show how the anomalous behaviour of titanium and nickel silicide formation can be explained thermodynamically by using the ?effective heat...

Black-hole-regulated star formation in massive galaxies

Science.gov (United States)

Martín-Navarro, Ignacio; Brodie, Jean P.; Romanowsky, Aaron J.; Ruiz-Lara, Tomás; van de Ven, Glenn

2018-01-01

Supermassive black holes, with masses more than a million times that of the Sun, seem to inhabit the centres of all massive galaxies. Cosmologically motivated theories of galaxy formation require feedback from these supermassive black holes to regulate star formation. In the absence of such feedback, state-of-the-art numerical simulations fail to reproduce the number density and properties of massive galaxies in the local Universe. There is, however, no observational evidence of this strongly coupled coevolution between supermassive black holes and star formation, impeding our understanding of baryonic processes within galaxies. Here we report that the star formation histories of nearby massive galaxies, as measured from their integrated optical spectra, depend on the mass of the central supermassive black hole. Our results indicate that the black-hole mass scales with the gas cooling rate in the early Universe. The subsequent quenching of star formation takes place earlier and more efficiently in galaxies that host higher-mass central black holes. The observed relation between black-hole mass and star formation efficiency applies to all generations of stars formed throughout the life of a galaxy, revealing a continuous interplay between black-hole activity and baryon cooling.

Black-hole-regulated star formation in massive galaxies.

Science.gov (United States)

Martín-Navarro, Ignacio; Brodie, Jean P; Romanowsky, Aaron J; Ruiz-Lara, Tomás; van de Ven, Glenn

2018-01-18

Supermassive black holes, with masses more than a million times that of the Sun, seem to inhabit the centres of all massive galaxies. Cosmologically motivated theories of galaxy formation require feedback from these supermassive black holes to regulate star formation. In the absence of such feedback, state-of-the-art numerical simulations fail to reproduce the number density and properties of massive galaxies in the local Universe. There is, however, no observational evidence of this strongly coupled coevolution between supermassive black holes and star formation, impeding our understanding of baryonic processes within galaxies. Here we report that the star formation histories of nearby massive galaxies, as measured from their integrated optical spectra, depend on the mass of the central supermassive black hole. Our results indicate that the black-hole mass scales with the gas cooling rate in the early Universe. The subsequent quenching of star formation takes place earlier and more efficiently in galaxies that host higher-mass central black holes. The observed relation between black-hole mass and star formation efficiency applies to all generations of stars formed throughout the life of a galaxy, revealing a continuous interplay between black-hole activity and baryon cooling.

Cloud Optimized Image Format and Compression

Science.gov (United States)

Becker, P.; Plesea, L.; Maurer, T.

2015-04-01

Cloud based image storage and processing requires revaluation of formats and processing methods. For the true value of the massive volumes of earth observation data to be realized, the image data needs to be accessible from the cloud. Traditional file formats such as TIF and NITF were developed in the hay day of the desktop and assumed fast low latency file access. Other formats such as JPEG2000 provide for streaming protocols for pixel data, but still require a server to have file access. These concepts no longer truly hold in cloud based elastic storage and computation environments. This paper will provide details of a newly evolving image storage format (MRF) and compression that is optimized for cloud environments. Although the cost of storage continues to fall for large data volumes, there is still significant value in compression. For imagery data to be used in analysis and exploit the extended dynamic range of the new sensors, lossless or controlled lossy compression is of high value. Compression decreases the data volumes stored and reduces the data transferred, but the reduced data size must be balanced with the CPU required to decompress. The paper also outlines a new compression algorithm (LERC) for imagery and elevation data that optimizes this balance. Advantages of the compression include its simple to implement algorithm that enables it to be efficiently accessed using JavaScript. Combing this new cloud based image storage format and compression will help resolve some of the challenges of big image data on the internet.

THE PSYCHOLOGICAL PECULIARITIES OF THE INFORMATION-COMMUNICATION COMPETENCE FORMATION

Directory of Open Access Journals (Sweden)

Михаил Михайлович Пьянников

2013-04-01

Full Text Available Informatization of society has significantly changed the paradigm of education, posing the new problems to the scientists. One of such problems is the formation of new conscience – conscience, whose inalienable part is the information culture. The information-communication competence is the basis for the formation of such conscience. In this connection the aim of study is the analysis of psychological peculiarities of the formation of information-communication competence and determination of the role of this personality new formation in conscience of a modern human. The characteristic features of psychological new formations, the stages of cultural development and the role of cultural level of society in the formation of world outlook of a child are studied in this work. In the result of study there was found out the basis of psychic development. The sphere of results application includes the conclusions received in the result of study, which can be used by scholars, who deal with the problem of psychic development of a child. In practice the data of study help to understand better the stages of skill formation and the role of elementary actions in the formation of complex behavioral system.DOI: http://dx.doi.org/10.12731/2218-7405-2013-1-33

Hydrogen or formate: Alternative key players in methanogenic degradation.

Science.gov (United States)

Schink, Bernhard; Montag, Dominik; Keller, Anja; Müller, Nicolai

2017-06-01

Hydrogen and formate are important electron carriers in methanogenic degradation in anoxic environments such as sediments, sewage sludge digestors and biogas reactors. Especially in the terminal steps of methanogenesis, they determine the energy budgets of secondary (syntrophically) fermenting bacteria and their methanogenic partners. The literature provides considerable data on hydrogen pool sizes in such habitats, but little data exist for formate concentrations due to technical difficulties in formate determination at low concentration. Recent evidence from biochemical and molecular biological studies indicates that several secondary fermenters can use both hydrogen and formate for electron release, and may do so even simultaneously. Numerous strictly anaerobic bacteria contain enzymes which equilibrate hydrogen and formate pools to energetically equal values, and recent measurements in sewage digestors and biogas reactors indicate that - beyond occasional fluctuations - the pool sizes of hydrogen and formate are indeed energetically nearly equivalent. Nonetheless, a thermophilic archaeon from a submarine hydrothermal vent, Thermococcus onnurineus, can obtain ATP from the conversion of formate to hydrogen plus bicarbonate at 80°C, indicating that at least in this extreme environment the pools of formate and hydrogen are likely to be sufficiently different to support such an unusual type of energy conservation. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

Cosmology and galaxy formation

International Nuclear Information System (INIS)

Rees, M.J.

1977-01-01

Implications of the massive halos and ''missing mass'' for galaxy formation are addressed; it is suggested that this mass consists of ''Population III'' stars that formed before the galaxies did. 19 references

Standardization of Licorice and TCM Formulations Using Eastern Blot Fingerprinting Analysis

OpenAIRE

Shoyama, Yukihiro

2013-01-01

To prepare the antiglycyrrhizin (GC) monoclonal antibody (MAb), GC was treated with NaIO4 resulting in aldehyde which can be combined with carrier protein. An antigen conjugate was performed by a matrix-assisted laser desorption/ionization TOF mass spectrometry to determine the hapten numbers in the conjugate. Anti-GC MAb was prepared from a hybridoma which was fixed from the spleen cells producing anti-GC MAb and the myeloma cells after immunization. The TCM and licorice extract were develop...

Understanding Collagen Organization in Breast Tumors to Predict and Prevent Metastasis

Science.gov (United States)

2015-11-01

mouse mammary tumor virus polyoma middle T (MMTV-PyMT) mice crossed with MMP13 KO mice, noted proportionately more “thin collagen fibers” (rela- tive to...mammary gland gene expression and increased tumor growth following social isolation. Cancer Prev. Res. 2, 850–861. Wohleb, E.S., Hanke, M.L., Corona , A.W...1:100 dilution of mouse anti-Collagen II (II-II6B3; Developmental Studies Hybridoma Bank, Iowa City, IA) or a mouse monoclonal anti-Collagen I ( Cat

Rat Monoclonal Antibodies Specific for LST1 Proteins

OpenAIRE

Schiller, Christian; Nitschké, Maximilian J. E.; Seidl, Alexander; Kremmer, Elisabeth; Weiss, Elisabeth H.

2009-01-01

The LST1 gene is located in the human MHC class III region and encodes transmembrane and soluble isoforms that have been suggested to play a role in the regulation of the immune response and are associated with inflammatory diseases such as rheumatoid arthritis. Here we describe the generation and characterization of the first monoclonal antibodies against LST1. Two hybridoma lines secreting monoclonal antibodies designated 7E2 and 8D12 were established. The 7E2 antibody detects recombinant a...

Qualitative analysis of the e-cloud formation

International Nuclear Information System (INIS)

Heifets, Samuel A

2002-01-01

The qualitative analysis of the electron cloud formation is presented. Two mechanisms of the cloud formation, generation of jets of primary photo-electrons and thermalization of electrons in the electron cloud, are analyzed and compared with simulations for the NLC damping ring [1

Stone Formation in the Infected Pediatric Enterocystoplasty

NARCIS (Netherlands)

R.B. Mathoera (Rejiv)

2003-01-01

markdownabstract__Abstract__ Proteus mirabilis is one of the most frequent bacterial agents that can induce infection stone formation by urease production. In recent years the influence of Proteus mirabilis on stone formation in enterocystoplasties has been primarily related to the presence of

QUESTION FORMATION OF BAHASA INDONESIA AS A SECOND LANGUAGE

Directory of Open Access Journals (Sweden)

zulfa Sakhiyya

2013-07-01

Full Text Available Abstract: This article aims to implement Processability Theory (PT to Bahasa Indonesia or Indonesian language and to identify developmental stages for question formation in the setting of Bahasa Indonesia as a second language (ISL. PT provides a theoretical framework in making predictions about the course of language development, in this case the question formation acquisition. This study proposes developmental stages of question formation in ISL setting by contrasting the lexical functional grammar of Indonesian question as compared to ESL question formation. Four stages of ISL question formation were proposed. The proposed stages serve as the basis for data analysis and to show its plausibility.

The Role of Emotions in Delusion Formation

Directory of Open Access Journals (Sweden)

Smurzyńska Adrianna

2016-12-01

Full Text Available The text concerns the role of emotions in delusion formation. Provided are definitions from DSM-V and DSM-IV-R and the problems found in those definitions. One of them, the problem of delusion formation, is described when providing cognitive theories of delusions. The core of the paper is a presentation of the emotional and affective disorders in delusions, especially Capgras delusion and Cotard delusion. The author provides a comparison of the kinds of delusions and the conclusions taken from neuroimaging studies. As a result of the fact that an explanation of delusion formation focusing on emotional problems turns out to be insufficient, the author provides examples of the reasoning impairments which coexist with them. At the end of the article, some hypotheses are proposed concerning the role of emotions and reasoning in delusion formation and the relation between belief disorders and emotional disorders.

Formation of soap bubbles by gas jet

Science.gov (United States)

Zhou, Maolei; Li, Min; Chen, Zhiyuan; Han, Jifeng; Liu, Dong

2017-12-01

Soap bubbles can be easily generated by various methods, while their formation process is complicated and still worth studying. A model about the bubble formation process was proposed in the study by Salkin et al. [Phys. Rev. Lett. 116, 077801 (2016)] recently, and it was reported that the bubbles were formed when the gas blowing velocity was above one threshold. However, after a detailed study of these experiments, we found that the bubbles could be generated in two velocity ranges which corresponded to the laminar and turbulent gas jet, respectively, and the predicted threshold was only effective for turbulent gas flow. The study revealed that the bubble formation was greatly influenced by the aerodynamics of the gas jet blowing to the film, and these results will help to further understand the formation mechanism of the soap bubble as well as the interaction between the gas jet and the thin liquid film.

Bonded exciplex formation: electronic and stereoelectronic effects.

Science.gov (United States)

Wang, Yingsheng; Haze, Olesya; Dinnocenzo, Joseph P; Farid, Samir; Farid, Ramy S; Gould, Ian R

2008-12-18

As recently proposed, the singlet-excited states of several cyanoaromatics react with pyridine via bonded-exciplex formation, a novel concept in photochemical charge transfer reactions. Presented here are electronic and steric effects on the quenching rate constants, which provide valuable support for the model. Additionally, excited-state quenching in poly(vinylpyridine) is strongly inhibited both relative to that in neat pyridine and also to conventional exciplex formation in polymers, consistent with a restrictive orientational requirement for the formation of bonded exciplexes. Examples of competing reactions to form both conventional and bonded exciplexes are presented, which illustrate the delicate balance between these two processes when their reaction energetics are similar. Experimental and computational evidence is provided for the formation of a bonded exciplex in the reaction of the singlet excited state of 2,6,9,10-tetracyanoanthracene (TCA) with an oxygen-substituted donor, dioxane, thus expanding the scope of bonded exciplexes.

Complexity and formative experiences

Directory of Open Access Journals (Sweden)

Roque Strieder

2017-12-01

Full Text Available The contemporaneity is characterized by instability and diversity calling into question certainties and truths proposed in modernity. We recognize that the reality of things and phenomena become effective as a set of events, interactions, retroactions and chances. This different frame extends the need for revision of the epistemological foundations that sustain educational practices and give them sense. The complex thinking is an alternative option for acting as a counterpoint to classical science and its reductionist logic and knowledge compartmentalization, as well as to answer to contemporary epistemological and educational challenges. It aims to associate different areas and forms of knowledge, without, however merge them, distinguishing without separating the several disciplines and instances of the realities. This study, in theoretical references, highlights the relevance of complex approaches to support formative experiences because also able to produce complexities in reflections about educational issues. We conclude that formative possibilities from complexity potentialize the resignification of human’s conception and the understanding of its singularity in interdependence; The understanding that pedagogical and educational activities is a constant interrogation about the possibilities of knowing the knowledge and reframe learning, far beyond knowing its functions and utilitarian purposes; and, as a formative possibility, places us on the trail of responsibility, not as something eventual, but present and indicative of freedom to choose to stay or go beyond.

The role of chloramine species in NDMA formation.

Science.gov (United States)

Selbes, Meric; Beita-Sandí, Wilson; Kim, Daekyun; Karanfil, Tanju

2018-09-01

N-nitrosodimethylamine (NDMA), a probable human carcinogen disinfection by-product, has been detected in chloraminated drinking water systems. Understanding its formation over time is important to control NDMA levels in distribution systems. The main objectives of this study were to investigate the role of chloramine species (i.e., monochloramine and dichloramine); and the factors such as pH, sulfate, and natural organic matter (NOM) influencing the formation of NDMA. Five NDMA precursors (i.e., dimethylamine (DMA), trimethylamine (TMA), N,N-dimethylisopropylamine (DMiPA), N,N-dimethylbenzylamine (DMBzA), and ranitidine (RNTD)) were carefully selected based on their chemical structures and exposed to varying ratios of monochloramine and dichloramine. All amine precursors reacted relatively fast to form NDMA and reached their maximum NDMA yields within 24 h in the presence of excess levels of chloramines (both mono- and dichloramine) or excess levels of dichloramine conditions (with limited monochloramine). When the formation of dichloramine was suppressed (i.e., only monochloramine existed in the system) over the 5 day contact time, NDMA formation from DMA, TMA, and DMiPA was drastically reduced (∼0%). Under monochloramine abundant conditions, however, DMBzA and RNTD showed 40% and 90% NDMA conversions at the end of 5 day contact time, respectively, with slow formation rates, indicating that while these amine precursors react preferentially with dichloramine to form NDMA, they can also react with monochloramine in the absence of dichloramine. NOM and pH influenced dichloramine levels that affected NDMA yields. NOM had an adverse effect on NDMA formation as it created a competition with NDMA precursors for dichloramine. Sulfate did not increase the NDMA formation from the two selected NDMA precursors. pH played a key role as it influenced both chloramine speciation and protonation state of amine precursors and the highest NDMA formation was observed at the p

On the formation of ball lightning

International Nuclear Information System (INIS)

Silberg, P.A.

1981-01-01

A plasma continuum model for the formation of ball lightning is developed based on a substantial number of reports that the ball is often in the discharge column of a previous lightning stroke. The usual method of setting up the plasma equation for a one-component electron plasma is used. An approximate equation for the plasma is derived from the describing equation which is then solved exactly in terms of the Jacobi elliptic functions. The formation of the ball is based on a nonlinearity of the plasma equation which uner certain circumstances permits the field to collapse into a small region. This collapse is interpreted to be ball lightning. The approximate equation derived for the plasma has the same form as a previous equation used to describe the formation of the fireball plasma. (author)

Forced migration, adolescence, and identity formation.

Science.gov (United States)

Anagnostopoulos, Dimitris C; Vlassopoulos, Maria; Lazaratou, Helen

2006-09-01

Adolescence is a complex biopsychosocial phenomenon. All the inner-subjective changes in adolescents take place within the context of a specific social environment, which offers the necessary ideological setting that adolescents must confront in the course of their identity formation. Forced migration creates conditions under which the adolescent Ego may be traumatized more easily, resulting in the development of defensive mechanisms, which may interfere with the natural process of identity formation. The aim of this paper is to investigate how a traumatic situation such as forced migration may affect the mechanisms of identity formation in adolescence. For this purpose, clinical material, consisting of two cases of psychoanalytical psychotherapy of adolescents who were forced to immigrate to Greece, is presented and discussed in a psychoanalytical theoretical framework, along with the historical-sociological background.

String cavitation formation inside fuel injectors

Science.gov (United States)

Reid, B. A.; Gavaises, M.; Mitroglou, N.; Hargrave, G. K.; Garner, C. P.; McDavid, R. M.

2015-12-01

The formation of vortex or ‘string’ cavitation has been visualised at pressures up to 2000 bar in an automotive-sized optical diesel fuel injector nozzle. The multi-hole nozzle geometry studied allowed observation of the hole-to-hole vortex interaction and, in particular, that of a bridging vortex in the sac region between the holes. Above a threshold Reynolds number, their formation and appearance during a 2 ms injection event was repeatable and independent of upstream pressure and cavitation number. In addition, two different hole layouts and threedimensional flow simulations have been employed to describe how, the relative positions of adjacent holes influenced the formation and hole-to-hole interaction of the observed string cavitation vortices, with good agreement between the experimental and simulation results being achieved.

New concepts in the abstract format of the Compositional Interchange Format

NARCIS (Netherlands)

D.A. van Beek; P.J. Collins (Pieter); D.E. Nadales Agut; J.E. Rooda (Jacobus); R.R.H. Schiffelers; A. Giua; M. Silva (Manuel); J. Zaytoon

2009-01-01

textabstractThe compositional interchange format for hybrid systems (CIF) supports inter-operability of a wide range of tools by means of model transformations to and from the CIF. Work on the CIF takes place in the FP7 Multiform project, and in several other European projects. The CIF consists of

Smectite formation in the presence of sulfuric acid: Implications for acidic smectite formation on early Mars

Science.gov (United States)

Peretyazhko, T. S.; Niles, P. B.; Sutter, B.; Morris, R. V.; Agresti, D. G.; Le, L.; Ming, D. W.

2018-01-01

The excess of orbital detection of smectite deposits compared to carbonate deposits on the martian surface presents an enigma because smectite and carbonate formations are both favored alteration products of basalt under neutral to alkaline conditions. We propose that Mars experienced acidic events caused by sulfuric acid (H2SO4) that permitted phyllosilicate, but inhibited carbonate, formation. To experimentally verify this hypothesis, we report the first synthesis of smectite from Mars-analogue glass-rich basalt simulant (66 wt% glass, 32 wt% olivine, 2 wt% chromite) in the presence of H2SO4 under hydrothermal conditions (∼200 °C). Smectites were analyzed by X-ray diffraction, Mössbauer spectroscopy, visible and near-infrared reflectance spectroscopy and electron microprobe to characterize mineralogy and chemical composition. Solution chemistry was determined by Inductively Coupled Plasma Mass Spectrometry. Basalt simulant suspensions in 11-42 mM H2SO4 were acidic with pH ≤ 2 at the beginning of incubation and varied from acidic (pH 1.8) to mildly alkaline (pH 8.4) at the end of incubation. Alteration of glass phase during reaction of the basalt simulant with H2SO4 led to formation of the dioctahedral smectite at final pH ∼3 and trioctahedral smectite saponite at final pH ∼4 and higher. Anhydrite and hematite formed in the final pH range from 1.8 to 8.4 while natroalunite was detected at pH 1.8. Hematite was precipitated as a result of oxidative dissolution of olivine present in Adirondack basalt simulant. Formation of secondary phases, including smectite, resulted in release of variable amounts of Si, Mg, Na and Ca while solubilization of Al and Fe was low. Comparison of mineralogical and solution chemistry data indicated that the type of smectite (i.e., dioctahedral vs trioctahedral) was likely controlled by Mg leaching from altering basalt and substantial Mg loss created favorable conditions for formation of dioctahedral smectite. We present a model

ON STAR FORMATION RATES AND STAR FORMATION HISTORIES OF GALAXIES OUT TO z ∼ 3

International Nuclear Information System (INIS)

Wuyts, Stijn; Foerster Schreiber, Natascha M.; Lutz, Dieter; Nordon, Raanan; Berta, Stefano; Genzel, Reinhard; Magnelli, Benjamin; Poglitsch, Albrecht; Altieri, Bruno; Andreani, Paola; Aussel, Herve; Daddi, Emanuele; Elbaz, David; Bongiovanni, Angel; Cepa, Jordi; Garcia, Ana Perez; Cimatti, Andrea; Koekemoer, Anton M.; Maiolino, Roberto; McGrath, Elizabeth J.

2011-01-01

We compare multi-wavelength star formation rate (SFR) indicators out to z ∼ 3 in the GOODS-South field. Our analysis uniquely combines U to 8 μm photometry from FIREWORKS, MIPS 24 μm and PACS 70, 100, and 160 μm photometry from the PEP, and Hα spectroscopy from the SINS survey. We describe a set of conversions that lead to a continuity across SFR indicators. A luminosity-independent conversion from 24 μm to total infrared luminosity yields estimates of L IR that are in the median consistent with the L IR derived from PACS photometry, albeit with significant scatter. Dust correction methods perform well at low-to-intermediate levels of star formation. They fail to recover the total amount of star formation in systems with large SFR IR /SFR UV ratios, typically occuring at the highest SFRs (SFR UV+ I R ∼> 100 M sun yr -1 ) and redshifts (z ∼> 2.5) probed. Finally, we confirm that Hα-based SFRs at 1.5 SED and SFR UV+IR provided extra attenuation toward H II regions is taken into account (A V,neb = A V,continuum /0.44). With the cross-calibrated SFR indicators in hand, we perform a consistency check on the star formation histories inferred from spectral energy distribution (SED) modeling. We compare the observed SFR-M relations and mass functions at a range of redshifts to equivalents that are computed by evolving lower redshift galaxies backward in time. We find evidence for underestimated stellar ages when no stringent constraints on formation epoch are applied in SED modeling. We demonstrate how resolved SED modeling, or alternatively deep UV data, may help to overcome this bias. The age bias is most severe for galaxies with young stellar populations and reduces toward older systems. Finally, our analysis suggests that SFHs typically vary on timescales that are long (at least several 100 Myr) compared to the galaxies' dynamical time.

Chemostratigraphy of Neoproterozoic Banded Iron Formation (BIF)

DEFF Research Database (Denmark)

Gaucher, Claudio; Sial, Alcides N.; Frei, Robert

2015-01-01

Sawawin BIF (Saudi Arabia), and the Jucurutu Formation of the Seridó Belt (NE Brazil). Lake Superior type BIFs are represented by the Tonian Shilu Group (South China) and the late Ediacaran Arroyo del Soldado Group (Yerbal and Cerro Espuelitas formations, Uruguay). Useful chemostratigraphic tools...

Harnessing Collaborative Annotations on Online Formative Assessments

Science.gov (United States)

Lin, Jian-Wei; Lai, Yuan-Cheng

2013-01-01

This paper harnesses collaborative annotations by students as learning feedback on online formative assessments to improve the learning achievements of students. Through the developed Web platform, students can conduct formative assessments, collaboratively annotate, and review historical records in a convenient way, while teachers can generate…

Cellular chain formation in Escherichia coli biofilms

DEFF Research Database (Denmark)

Vejborg, Rebecca Munk; Klemm, Per

2009-01-01

; type I fimbriae expression significantly reduced cellular chain formation, presumably by steric hindrance. Cellular chain formation did not appear to be specific to E coli K-12. Although many urinary tract infection (UTI) isolates were found to form rather homogeneous, flat biofilms, three isolates...

Program PLOTC4 (Version 86-1). Plot evaluated data from the ENDF/B format and/or experimental data which is in a computation format

International Nuclear Information System (INIS)

Cullen, D.E.

1986-09-01

Experimental and evaluated nuclear reaction data are world-wide compiled in EXFOR format and ENDF format, respectively. The computer program PLOTC4 described in the present document plots data from both formats; EXFOR data must be converted first to a ''computation format''. The program is available costfree from the IAEA Nuclear Data Section, upon request. (author)

Carbon nanotube formation by laser direct writing

International Nuclear Information System (INIS)

Wu, Y.-T.; Su, H.-C.; Tsai, C.-M.; Liu, K.-L.; Chen, G.-D.; Huang, R.-H.; Yew, T.-R.

2008-01-01

This letter presents carbon nanotube (CNT) formation by laser direct writing using 248 nm KrF excimer pulsed laser in air at room temperature, which was applied to irradiate amorphous carbon (a-C) assisted by Ni catalysts underneath for the transformation of carbon species into CNTs. The CNTs were synthesized under appropriate combination of laser energy density and a-C thickness. The growth mechanism and key parameters to determine the success of CNT formation were also discussed. The demonstration of the CNT growth by laser direct writing in air at room temperature opens an opportunity of in-position CNT formation at low temperatures

Formation of nuclear security culture in Ukraine

International Nuclear Information System (INIS)

Gavrilyuk, V.Yi.; Gavrilyuk-Burakova, A.V.; Drapej, S.S.; Parkhomenko, V.V.; Proskuryin, D.V.; Romanova, O.P.

2014-01-01

Issues of nuclear security culture formation are considered in the article. Information on establishing and activity of Working Group for formation and development of nuclear security culture being held during 2010 - 2013 is given. An issue of regulation of activity on formation and development of nuclear security culture is illustrated. Analysis of the survey results regarding efficiency assessment of the work aimed to form and develop of nuclear security culture of nuclear facilities is carried out. The results show that the nuclear security culture of the most of nuclear facilities in Ukraine has been formed and is at the stage of development

Biofilm formation in a hot water system

DEFF Research Database (Denmark)

Bagh, L.K.; Albrechtsen, Hans-Jørgen; Arvin, Erik

2002-01-01

The biofilm formation rate was measured in situ in a hot water system in an apartment building by specially designed sampling equipment, and the net growth of the suspended bacteria was measured by incubation of water samples with the indigeneous bacteria. The biofilm formation rate reached......, in the sludge, or in the water from the distribution system was negligible. This indicated that bacterial growth took place on the inner surfaces in the hot water system and biofilm formation and detachment of bacteria could account for most of the suspended bacteria actually measured in hot water. Therefore...

Formation of adduct of cerium (4) thenoyltrifluoroacetonate

International Nuclear Information System (INIS)

Anyfrieva, S.I.; Polyakova, G.V.; Snezhko, N.I.; Pechurova, N.I.; Martynenko, L.I.; Spitsyn, V.I.

1981-01-01

Adduct formation of thenoyltrifluoroacetonate of Ce(4) [Ce(TTFA) 4 ] with seven nitrogen- and oxygen-containing donor additional ligands is studied using the methods of IR-spectroscopy, derivatography, X-ray phase analysis. The presence of formation of Ce(TTFA) 4 adducts with phosphorus-containing additional ligands tributyl phosphate (TBP), trioctylphosphine oxide (TOPO), triphenylphosphine oxide (TPPO); α, α'-dipyridyl (Dipy) and o-phenanthroline (Phen) is established. The adduct Ce(TTFA) 4 stable to reduction is formed with Dipy, and in the case of Phen, TBP, TOPO, TPPO in the process of adduct formation the reduction of Ce(4) to Ce(3) takes place [ru

Update to the R33 cross section file format

International Nuclear Information System (INIS)

Vickridge, I.C.

2003-01-01

In September 1991, in response to the workshop on cross sections for Ion Beam Analysis (IBA) held in Namur (July 1991, Nuclear Instruments and Methods B66(1992)), a simple ascii format was proposed to facilitate transfer and collation of nuclear reaction cross section data for Ion Beam Analysis (IBA) and especially for Nuclear Reaction Analysis (NRA). Although intended only as a discussion document, the ascii format - referred to as the R33 (Report 33) format - has become a de facto standard. In the decade since this first proposal there have been spectacular advances in computing power and in software usability, however the cross-platform compatibility of the ascii character set has ensured that the need for an ascii format remains. Nuclear reaction cross section data for Nuclear Reaction analysis has been collected and archived on internet web sites over the last decade. This data has largely been entered in the R33 format, although there is a series of elastic cross sections that are expressed as the ratio to the corresponding Rutherford cross sections that have been entered in a format referred to as RTR (ratio to Rutherford). During this time the R33 format has been modified and added to - firstly to take into account angular distributions, which were not catered for in the first proposal, and more recently to cater for elastic cross sections expressed as the ratio-to- Rutherford, which it is useful to have for some elastic scattering programs. It is thus timely to formally update the R33 format. There also exists the large nuclear cross section data collections of the Nuclear Data Network - of which the core centres are the OECD NEA Nuclear Data Bank, the IAEA Nuclear Data Section, the Brookhaven National Laboratory National Nuclear Data Centre and CJD IPPE Obninsk, Russia. The R33 format is now proposed to become a legal computational format for the NDN. It is thus also necessary to provide an updated formal definition of the R33 format in order to provide

Adolescent Violent Victimization and Precocious Union Formation*

Science.gov (United States)

C. Kuhl, Danielle; Warner, David F.; Wilczak, Andrew

2013-01-01

This article bridges scholarship in criminology and family sociology by extending arguments about “precocious exits” from adolescence to consider early union formation as a salient outcome of violent victimization for youths. Research indicates that early union formation is associated with several negative outcomes; yet the absence of attention to union formation as a consequence of violent victimization is noteworthy. We address this gap by drawing on life course theory and data from the National Longitudinal Study of Adolescent Health (Add Health) to examine the effect of violent victimization (“street” violence) on the timing of first co-residential union formation—differentiating between marriage and cohabitation—in young adulthood. Estimates from Cox proportional hazard models show that adolescent victims of street violence experience higher rates of first union formation, especially marriage, early in the transition to adulthood; however, this effect declines with age, as such unions become more normative. Importantly, the effect of violent victimization on first union timing is robust to controls for nonviolent delinquency, substance abuse, and violent perpetration. We conclude by discussing directions for future research on the association between violent victimization and coresidential unions with an eye toward the implications of such early union formation for desistance. PMID:24431471

THE BLACK HOLE FORMATION PROBABILITY

International Nuclear Information System (INIS)

Clausen, Drew; Piro, Anthony L.; Ott, Christian D.

2015-01-01

A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P BH (M ZAMS ). Although we find that it is difficult to derive a unique P BH (M ZAMS ) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P BH (M ZAMS ) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P BH (M ZAMS ) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment

The Black Hole Formation Probability

Science.gov (United States)

Clausen, Drew; Piro, Anthony L.; Ott, Christian D.

2015-02-01

A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P BH(M ZAMS). Although we find that it is difficult to derive a unique P BH(M ZAMS) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P BH(M ZAMS) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P BH(M ZAMS) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment.

Formation control of unicycle robots using virtual structure approach

NARCIS (Netherlands)

Sadowska, A.D.; Huijberts, H.J.C.; Kostic, D.; Wouw, van de N.; Nijmeijer, H.

2011-01-01

This paper addresses the problem of formation control of groups of unicycle robots with possibly time-varying formation shapes. To solve the problem, we propose two simple distributed formation control algorithms based on the virtual structure approach. We prove exponential convergence of error

ENDF/X: an Extended ENDF Format (Evolution, not Revolution)

International Nuclear Information System (INIS)

Cullen, Dermott E.

2012-01-01

Recently there has been yet another round of complaints about the ENDF format not being modern and general enough to handle today's nuclear data. This has led to suggestions to abandon the current ENDF and move on to a new format. The complaints I hear I fear are based upon not understanding the primary purpose of ENDF and a lack of experience in using the ENDF format and not being flexible to enough to deal with the current format. Personally I do not think that any changes to the ENDF format are Necessary. But here I address the complaints that I have recently heard about the limitations of the ENDF format, and I suggest minor changes that will completely handle these complaints. In turn I would ask those who are complaining and feel that extensions are needed Please give us some examples where these extensions are Needed. Personally I am not aware of any such data, but I am keeping an open mind and I would love to see examples that really Require extensions. I propose a few fairly simple extensions to the current ENDF/B format; what I call ENDF/X. Compared to other suggested revolutionary changes, my evolutionary approach has the advantage that it maintains compatibility with the existing ENDF/B format that we have used successfully for almost fifty years, and still allows the format to be extended for use with other types of data. In addition to my suggested changes to the ENDF/B format I also include a brief history of ENDF/B, in the hope that the experience we have gained over the last almost 50 years will be of help to the present generation of nuclear data developers and users. Please let's not make the mistake of learning nothing from history. Lastly I finish by identifying what I see as the weak point in the current infrastructure that we use to handle evaluated nuclear data; it me it is not the format of the data. (author)

Star formation properties of galaxy cluster A1767

International Nuclear Information System (INIS)

Yan, Peng-Fei; Li, Feng; Yuan, Qi-Rong

2015-01-01

Abell 1767 is a dynamically relaxed, cD cluster of galaxies with a redshift of 0.0703. Among 250 spectroscopically confirmed member galaxies within a projected radius of 2.5r 200 , 243 galaxies (∼ 97%) are spectroscopically covered by the Sloan Digital Sky Survey. Based on this homogeneous spectral sample, the stellar evolutionary synthesis code STARLIGHT is applied to investigate the stellar populations and star formation histories of galaxies in this cluster. The star formation properties of galaxies, such as mean stellar ages, metallicities, stellar masses, and star formation rates, are presented as functions of local galaxy density. A strong environmental effect is found such that massive galaxies in the high-density core region of the cluster tend to have higher metallicities, older mean stellar ages, and lower specific star formation rates (SSFRs), and their recent star formation activities have been remarkably suppressed. In addition, the correlations of the metallicity and SSFR with stellar mass are confirmed. (paper)

Search for Formation Criteria for Globular Cluster Systems

Science.gov (United States)

Nuritdinov, S. N.; Mirtadjieva, K. T.; Tadjibaev, I. U.

2005-01-01

Star cluster formation is a major mode of star formation in the extreme conditions of interacting galaxies and violent starbursts. By studying ages and metallicities of young metal-enhanced star clusters in mergers / merger remnants we can learn about the violent star formation history of these galaxies and eventually about galaxy formation and evolution. We will present a new set of evolutionary synthesis models of our GALEV code specially developed to account for the gaseous emission of presently forming star clusters and an advanced tool to compare large model grids with multi-color broad-band observations becoming presently available in large amounts. Such observations are an ecomonic way to determine the parameters of young star clusters as will be shown in the presentation. First results of newly-born clusters in mergers and starburst galaxies are presented and compared to the well-studied old globulars and interpreted in the framework of galaxy formation / evolution.

A theory of biological pattern formation

OpenAIRE

Gierer, Alfred; Meinhardt, H.

2006-01-01

The paper addresses the formation of striking patterns within originally near-homogenous tissue, the process prototypical for embryology, and represented in particularly puristic form by cut sections of hydra regenerating a complete animal with head and foot. Essential requirements are autocatalytic, self-enhancing activation, combined with inhibitory or depletion effects of wider range - “lateral inhibition”. Not only de-novo-pattern formation, but also well known, striking features of devel...

Formation of coronal cavities

International Nuclear Information System (INIS)

An, C.H.; Suess, S.T.; Tandberg-Hanssen, E.; Steinolfson, R.S.

1986-01-01

A theoretical study of the formation of a coronal cavity and its relation to a quiescent prominence is presented. It is argued that the formation of a cavity is initiated by the condensation of plasma which is trapped by the coronal magnetic field in a closed streamer and which then flows down to the chromosphere along the field lines due to lack of stable magnetic support against gravity. The existence of a coronal cavity depends on the coronal magnetic field strength; with low strength, the plasma density is not high enough for condensation to occur. Furthermore, we suggest that prominence and cavity material is supplied from the chromospheric level. Whether a coronal cavity and a prominence coexist depends on the magnetic field configuration; a prominence requires stable magnetic support

Radiation induced formation of giant cells (Saccharomyces uvarum). Pt. 1

Energy Technology Data Exchange (ETDEWEB)

Baumstark-Khan, C; Schnitzler, L; Rink, H

1984-02-01

X-irradiated yeast cells (Saccharomyces uvarum) grown in liquid media stop mitosis and form giant cells. Chitin ring formation, being a prerequisite for cell separation, was studied by fluorescence microscopy using Calcofluor White, a chitin specific dye. Experiments with inhibitors of DNA synthesis (hydroxyurea) and chitin synthesis (polyoxin D) demonstrate chitin ring formation to be dependent on DNA synthesis, whereas bud formation is independent of DNA synthesis and chitin ring formation respectively. Basing on these results the formation of X-ray induced giant cells implies one DNA replication which in turn induces the formation of only one chitin ring between mother cell and giant bud. Obviously no septum can be formed. Thus cell separation does not occur, but the bud already formed, produces another bud demonstrating that bud formation itself is independent of DNA synthesis.

Using an ACTIVE teaching format versus a standard lecture format for increasing resident interaction and knowledge achievement during noon conference: a prospective, controlled study

Science.gov (United States)

2014-01-01

Background The traditional lecture is used by many residency programs to fulfill the mandate for regular didactic sessions, despite limited evidence to demonstrate its effectiveness. Active teaching strategies have shown promise in improving medical knowledge but have been challenging to implement within the constraints of residency training. We developed and evaluated an innovative structured format for interactive teaching within the residency noon conference. Methods We developed an ACTIVE teaching format structured around the following steps: assemble (A) into groups, convey (C) learning objectives, teach (T) background information, inquire (I) through cases and questions, verify (V) understanding, and explain (E) answer choices and educate on the learning points. We conducted a prospective, controlled study of the ACTIVE teaching format versus the standard lecture format, comparing resident satisfaction, immediate knowledge achievement and long-term knowledge retention. We qualitatively assessed participating faculty members’ perspectives on the faculty development efforts and the feasibility of teaching using the ACTIVE format. Results Sixty-nine internal medicine residents participated in the study. Overall, there was an improvement in perceived engagement using the ACTIVE teaching format (4.78 vs. 3.80, P teaching format (overall absolute score increase of 11%, P = 0.04) and a trend toward improvement in long-term knowledge retention. Faculty members felt adequately prepared to use the ACTIVE teaching format, and enjoyed teaching with the ACTIVE teaching format more than the standard lecture. Conclusions A structured ACTIVE teaching format improved resident engagement and initial knowledge, and required minimal resources. The ACTIVE teaching format offers an exciting alternative to the standard lecture for resident noon conference and is easy to implement. PMID:24985781

A Decentralized Approach to Formation Flight Routing

NARCIS (Netherlands)

Visser, H.G.; Lopes dos Santos, Bruno F.; Verhagen, C.M.A.

2016-01-01

This paper describes the development of an optimization-based cooperative planning system for the efficient routing and scheduling of flight formations. This study considers the use of formation flight as a means to reduce the overall fuel consumption of civil aviation in long-haul operations. It

Combinations of partners’ joint venture formation motives

NARCIS (Netherlands)

Klijn, E.; Reuer, J.J.; Buckley, P.J.; Glaister, K.W.

2011-01-01

Purpose – Prior research on joint venture (JV) formation often examines a single focal firm and assumes it has a single motive for collaboration. This study seeks to investigate how formation motives of partner firms are symmetrically coupled. It considers motives in the context of different

Enhancing the Lecture: Revitalizing the Traditional Format.

Science.gov (United States)

Bonwell, Charles C.

1996-01-01

The traditional lecture format of college courses can be enhanced by including active learning designed to further course goals of learning knowledge, developing skills, or fostering attitudes. Techniques suggested include using pauses, short writing periods, think-pair-share activities, formative quizzes, lecture summaries, and several assessment…

Formation of a compact toroid for enhanced efficiency

Energy Technology Data Exchange (ETDEWEB)

Mozgovoy, A. G. [P.N. Lebedev Physical Institute, Moscow 119991 (Russian Federation); Romadanov, I. V.; Ryzhkov, S. V., E-mail: ryzhkov@power.bmstu.ru [Bauman Moscow State Technical University, Moscow 105005 (Russian Federation)

2014-02-15

We report here our results on the formation of a plasma configuration with the generic name of compact toroid (CT). A method of compact toroid formation to confine, heat and compress a plasma is investigated. Formation of a compact torus using an additional toroidal magnetic field helps to increase the plasma current to a maintainable level of the original magnetic field. We design the Compact Toroid Challenge (CTC) experiment in order to improve the magnetic flux trapping during field reversal in the formation of a compact toroid. The level of the magnetic field immersed in the plasma about 70% of the primary field is achieved. The CTC device and scheme of high level capturing of magnetic flux are presented.

Timing of College Enrollment and Family Formation Decisions

DEFF Research Database (Denmark)

Humlum, Maria; Kristoffersen, Jannie H. G.; Vejlin, Rune Majlund

The level of progression of an individual’s educational or labor market career is a potentially important factor for family formation decisions. We address this issue by considering the effects of a particular college admission system on family formation. We show that the admission system affects...... system to estimate the effect of being above the admission requirement in the year of application on later family formation decisions. We find that the admission system has substantial effects on the timing of family formation and, specifically, that the timing of college enrollment is an important...... determinant hereof. This suggests that career interruptions such as delays in the educational system can have large effects on family decision - making....

Report formatting in laboratory medicine - a call for harmony.

Science.gov (United States)

Jones, Graham R D; Legg, Michael

2018-04-19

The results of medical laboratory testing are only useful if they lead to appropriate actions by medical practitioners and/or patients. An underappreciated component of the medical testing process is the transfer of the information from the laboratory report into the reader's brain. The format of laboratory reports can be determined by the testing laboratory, which may issue a formatted report, or by electronic systems receiving information from laboratories and controlling the report format. As doctors can receive information from many laboratories, interpreting information from reports in a safe and rapid manner is facilitated by having similar report layouts and formats. Using Australia as an example, there is a wide variation in report formats in spite of a body of work to define standards for reporting. In addition to standardising of report formats, consideration needs to be given to optimisation of report formatting to facilitate rapid and unambiguous reading of the report and also interpretation of the data. Innovative report formats have been developed by some laboratories; however, wide adoption has not followed. The need to balance uniformity of reporting with appropriate innovation is a challenge for safe reporting of laboratory results. This paper discusses the current status and opportunity for improvement in safety and efficiency of the reading of laboratory reports, using current practise and developments in Australia as examples.

Bearing-Only Formation Control for Cascade Multirobots

Directory of Open Access Journals (Sweden)

Qing Han

2016-01-01

Full Text Available A new formation control method is proposed, which is used to queue multirobots in a single-direction cascade structure. In the cascade formation, each robot is a follower for the previous robot and a leader for the next robot, and the robots in the middle act as both leader and follower. The follower robot can only observe the bearing information of the leader robot. The observability of the cascade leader-follower formation is studied, which shows that the bearing-only observation meets the observability conditions required for the nonlinear system. Based on the bearing-only observations, the unscented Kalman filter (UKF is employed for the state estimation of the leader and the follower robots at all levels, which enables the real-time movement control of the follower robots via the input-output feedback control. Simulation results demonstrate that the proposed approach can efficiently control the formation of multirobots as desired.

Rethinking pattern formation in reaction-diffusion systems

Science.gov (United States)

Halatek, J.; Frey, E.

2018-05-01

The present theoretical framework for the analysis of pattern formation in complex systems is mostly limited to the vicinity of fixed (global) equilibria. Here we present a new theoretical approach to characterize dynamical states arbitrarily far from (global) equilibrium. We show that reaction-diffusion systems that are driven by locally mass-conserving interactions can be understood in terms of local equilibria of diffusively coupled compartments. Diffusive coupling generically induces lateral redistribution of the globally conserved quantities, and the variable local amounts of these quantities determine the local equilibria in each compartment. We find that, even far from global equilibrium, the system is well characterized by its moving local equilibria. We apply this framework to in vitro Min protein pattern formation, a paradigmatic model for biological pattern formation. Within our framework we can predict and explain transitions between chemical turbulence and order arbitrarily far from global equilibrium. Our results reveal conceptually new principles of self-organized pattern formation that may well govern diverse dynamical systems.

Pebble pile-up and planetesimal formation at the snow line

Science.gov (United States)

Drazkowska, J.

2017-09-01

The planetesimal formation stage represents a major gap in our understanding of planet formation process. Because of this, the late-stage planet accretion models typically make arbitrary assumptions about planetesimals and pebbles distribution, while the state-of-the-art dust evolution models predict no or little planetesimal formation. With this contribution, I present a step toward bridging the gap between the early and late stages of planet formation by models that connect dust coagulation and planetesimal formation. With the aid of evaporation, outward diffusion, and re-condensation of water vapor, pile-up of large pebbles is formed outside of the snow line that facilitates planetesimal formation by streaming instability.

Method and apparatus for nuclear heating of oil-bearing formations

International Nuclear Information System (INIS)

Alspaw, D.I.

1979-01-01

A method and apparatus are provided for using heat generated by absorption of radiation from nuclear waste materials to reduce the viscosity of petroleum products contained within a subsurface earth formation. The nuclear waste material is positioned in a salt water formation underlying the subsurface earth formation so that the radiation emitted by the material heats the salt water formation. conduction and convection transfer the heat to the subsurface earth formation, raising the temperature and thereby reducing the viscosity of the petroleum products. To prevent radioactive contamination within the salt water formation, the nuclear waste material may be encapsulated in a material selected to absorb alpha and beta radiation

Experimental Investigation of Effect on Hydrate Formation in Spray Reactor

Directory of Open Access Journals (Sweden)

Jianzhong Zhao

2015-01-01

Full Text Available The effects of reaction condition on hydrate formation were conducted in spray reactor. The temperature, pressure, and gas volume of reaction on hydrate formation were measured in pure water and SDS solutions at different temperature and pressure with a high-pressure experimental rig for hydrate formation. The experimental data and result reveal that additives could improve the hydrate formation rate and gas storage capacity. Temperature and pressure can restrict the hydrate formation. Lower temperature and higher pressure can promote hydrate formation, but they can increase production cost. So these factors should be considered synthetically. The investigation will promote the advance of gas storage technology in hydrates.

Jet formation in shock-heavy gas bubble interaction

Institute of Scientific and Technical Information of China (English)

Zhi-Gang Zhai; Ting Si; Li-Yong Zou; Xi-Sheng Luo

2013-01-01

The influences of the acoustic impedance and shock strength on the jet formation in shock-heavy gas bubble interaction are numerically studied in this work.The process of a shock interacting with a krypton or a SF6 bubble is studied by the numerical method VAS2D.As a validation,the experiments of a SF6 bubble accelerated by a planar shock were performed.The results indicate that,due to the mismatch of acoustic impedance,the way of jet formation in heavy gas bubble with different species is diversified under the same initial condition.With respect to the same bubble,the manner of jet formation is also distinctly different under different shock strengths.The disparities of the acoustic impedance result in different effects of shock focusing in the bubble,and different behaviors of shock wave inside and outside the bubble.The analyses of the wave pattern and the pressure variation indicate that the jet formation is closely associated with the pressure perturbation.Moreover,the analysis of the vorticity deposition,and comparisons of circulation and baroclinic torque show that the baroclinic vorticity also contributes to the jet formation.It is concluded that the pressure perturbation and baroclinic vorticity deposition are the two dominant factors for the jet formation in shock-heavy gas bubble interaction.

Research on formation of microsatellite communication with genetic algorithm.

Science.gov (United States)

Wu, Guoqiang; Bai, Yuguang; Sun, Zhaowei

2013-01-01

For the formation of three microsatellites which fly in the same orbit and perform three-dimensional solid mapping for terra, this paper proposes an optimizing design method of space circular formation order based on improved generic algorithm and provides an intersatellite direct spread spectrum communication system. The calculating equation of LEO formation flying satellite intersatellite links is guided by the special requirements of formation-flying microsatellite intersatellite links, and the transmitter power is also confirmed throughout the simulation. The method of space circular formation order optimizing design based on improved generic algorithm is given, and it can keep formation order steady for a long time under various absorb impetus. The intersatellite direct spread spectrum communication system is also provided. It can be found that, when the distance is 1 km and the data rate is 1 Mbps, the input wave matches preferably with the output wave. And LDPC code can improve the communication performance. The correct capability of (512, 256) LDPC code is better than (2, 1, 7) convolution code, distinctively. The design system can satisfy the communication requirements of microsatellites. So, the presented method provides a significant theory foundation for formation-flying and intersatellite communication.

Protocol for Communication Networking for Formation Flying

Science.gov (United States)

Jennings, Esther; Okino, Clayton; Gao, Jay; Clare, Loren

2009-01-01

An application-layer protocol and a network architecture have been proposed for data communications among multiple autonomous spacecraft that are required to fly in a precise formation in order to perform scientific observations. The protocol could also be applied to other autonomous vehicles operating in formation, including robotic aircraft, robotic land vehicles, and robotic underwater vehicles. A group of spacecraft or other vehicles to which the protocol applies could be characterized as a precision-formation- flying (PFF) network, and each vehicle could be characterized as a node in the PFF network. In order to support precise formation flying, it would be necessary to establish a corresponding communication network, through which the vehicles could exchange position and orientation data and formation-control commands. The communication network must enable communication during early phases of a mission, when little positional knowledge is available. Particularly during early mission phases, the distances among vehicles may be so large that communication could be achieved only by relaying across multiple links. The large distances and need for omnidirectional coverage would limit communication links to operation at low bandwidth during these mission phases. Once the vehicles were in formation and distances were shorter, the communication network would be required to provide high-bandwidth, low-jitter service to support tight formation-control loops. The proposed protocol and architecture, intended to satisfy the aforementioned and other requirements, are based on a standard layered-reference-model concept. The proposed application protocol would be used in conjunction with conventional network, data-link, and physical-layer protocols. The proposed protocol includes the ubiquitous Institute of Electrical and Electronics Engineers (IEEE) 802.11 medium access control (MAC) protocol to be used in the datalink layer. In addition to its widespread and proven use in

HDF5-Ph-Data format - Version 0.2 Draft

OpenAIRE

Antonino Ingargiola

2014-01-01

This format has been renamed Photon-HDF5 and the latest specification can be found at http://photon-hdf5.readthedocs.org/. This document contains the specifications for the HDF5-Ph-Data format. This format allows saving single-molecule spectroscopy experiments when there is at least a stream of photon timestamps. It has been envisioned as a standard container format for a broad range of experiments involving confocal microcopy. Notable examples are confocal smFRET experiments (with or wit...

Program ECSX4 (version 78-1): conversion of experimentally measured cross-section data from the four-center-exchange (X-4) format to the Livermore ECSIL format

International Nuclear Information System (INIS)

Cullen, D.E.; Perkins, S.T.

1978-01-01

A computer code called ECSX4 converts experimentally measured cross-section data from the four-center-exchange (X-4) format to the Livermore Experimental Cross-Section Information Library (ECSIL) format. The major advantage of this program is that it converts the variable format and dimensioned data of the X-4 format to the fixed-field format and consistent set of units of the ECSIL format. This consistency greatly simplifies the subsequent use of the data for cross-section evaluations. 2 figures, 3 tables

Aspartate inhibits Staphylococcus aureus biofilm formation.

Science.gov (United States)

Yang, Hang; Wang, Mengyue; Yu, Junping; Wei, Hongping

2015-04-01

Biofilm formation renders Staphylococcus aureus highly resistant to conventional antibiotics and host defenses. Four D-amino acids (D-Leu, D-Met, D-Trp and D-Tyr) have been reported to be able to inhibit biofilm formation and disassemble established S. aureus biofilms. We report here for the first time that both D- and L-isoforms of aspartate (Asp) inhibited S. aureus biofilm formation on tissue culture plates. Similar biofilm inhibition effects were also observed against other staphylococcal strains, including S. saprophyticus, S. equorum, S. chromogenes and S. haemolyticus. It was found that Asp at high concentrations (>10 mM) inhibited the growth of planktonic N315 cells, but at subinhibitory concentrations decreased the cellular metabolic activity without influencing cell growth. The decreased cellular metabolic activity might be the reason for the production of less protein and DNA in the matrix of the biofilms formed in the presence of Asp. However, varied inhibition efficacies of Asp were observed for biofilms formed by clinical staphylococcal isolates. There might be mechanisms other than decreasing the metabolic activity, e.g. the biofilm phenotypes, affecting biofilm formation in the presence of Asp. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.