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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
451

Immunohistochemical Comparison of Markers for Wound Healing on Plastic-Embedded and Frozen Mucosal Tissue

Mai, Ronald, Gedrange, Tomasz, Leonhardt, Henry, Sievers, Nicole, Lauer, Günter 04 March 2014 (has links) (PDF)
Immunohistologic investigations of wound healing in human oral mucosa require specific cell biological markers as well as consecutive small biopsies. Small specimens are ideally embedded in plastic (methylmethacrylate, MMA) resin due to their miniature size. This limits the use of antibodies for these markers. In this immunohistochemical study, the distribution of wound healing markers, e.g. cytokeratin (CK), laminin, collagen IV, vimentin, vinculin and fibronectin, were compared between semithin sections of plastic-embedded tissue and frozen sections of mucosal tissue in order to assess their use for future investigations. The antibodies against laminin, collagen IV and CK 1/2/10/11, 5/6, 13, 14, 17, 19 gave comparable staining patterns on cryostat sections of attached mucosa and on semithin sections of MMA-embedded attached mucosa. In the epithelial cell layers, the following distribution of CK immunostaining was observed: The basal cell layer was positive for CK 5/6, CK 14 and CK 19; the intermediate cell layer for CK 13, CK 17 and CK 1/2/10/11, and the superficial cell layer for CK 13 and CK 1/2/10/11. For most of these antibodies, enzyme digestion with 0.1% trypsin was adequate for demasking the antigens, except for anti-CK 14, anti-CK 17 and anti-laminin; predigestion with 0.4% pepsin in 0.01 N HCl gave similar staining results. The antibodies against vimentin, vinculin, fibronectin and CK 4 showed no affinity or a reciprocal reaction on the semithin sections. Therefore, the antibodies against CK 1/2/10/11; 5/6; 13; 14; 17, and 19, as well as the basement proteins laminin and collagen IV are deemed markers suitable on semithin sections of plastic-embedded attached oral mucosa. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
452

A search for the standard model Higgs Boson in the neutrino channel using the DELPHI detector at LEP2

McPherson, Gavin James January 1999 (has links)
No description available.
453

Presentation of the Digital School Journal: Revista Escolar de la Olimpiada Iberoamericana de Matemática, Sponsored by the O.E.I. Organización de Estados Iberoamericanos para la Educación, la Ciencia y la Cultura

Bellot Rosado, Francisco 12 April 2012 (has links) (PDF)
The purpose of this paper is to present all participants of the Dresden Conference the digital School Journal Revista Escolar de la Olimpiada Iberoamericana de Matemática, online since May-June 2002, with lmost 16,000 subscribers at current issue number 32. Subscribers are based all over the world, but mostly in Spain, Portugal and Latin America.
454

Coupled multi-group neutron photon transport for the simulation of high-resolution gamma-ray spectroscopy applications

Burns, Kimberly Ann 02 July 2009 (has links)
The accurate and efficient simulation of coupled neutron-photon problems is necessary for several important radiation detection applications. Examples include the detection of nuclear threats concealed in cargo containers and prompt gamma neutron activation analysis for nondestructive determination of elemental composition of unknown samples. In these applications, high-resolution gamma-ray spectrometers are used to preserve as much information as possible about the emitted photon flux, which consists of both continuum and characteristic gamma rays with discrete energies. Monte Carlo transport is the most commonly used modeling tool for this type of problem, but computational times for many problems can be prohibitive. This work explored the use of coupled Monte Carlo-deterministic methods for the simulation of neutron-induced photons for high-resolution gamma-ray spectroscopy applications. A method was developed for the implementation of coupled neutron-photon problems into RAdiation Detection Scenario Analysis Toolbox (RADSAT), a computer code that couples the complementary strengths of discrete-ordinate and Monte Carlo approaches to obtain high-resolution detector responses. Central to this work was the development of a method for generating multi-group neutron-photon cross-sections in a way that separates the discrete and continuum photon emissions so that the key signatures in neutron activation analysis (i.e., the characteristic line energies) are preserved. The mechanics of the cross-section preparation method are described and contrasted with standard neutron-gamma cross-section sets. These custom cross-sections were then applied to several benchmark problems using the method developed in this work. Multi-group results for neutron and photon flux are compared to MCNP results. Finally, calculated responses of high-resolution spectrometers were compared. The added computational efficiency of the coupled Monte Carlo-deterministic method and the positive agreement achieved in the code-to-code verification make the integration of the coupled neutron-photon method into RADSAT a promising endeavor.
455

Genotyping and Mutation Detection In Situ : Development and application of single-molecule techniques

Grundberg, Ida January 2011 (has links)
The human body is composed of trillions of cells closely working together to maintain a functional organism. Every cell is unique in molecular composition and can acquire genetic variations that might cause it to turn pathological. It is essential to develop improved tools to better understand the development of normal and disease tissue, ideally enabling single-cell expression studies in preserved context of complex tissue with single-nucleotide resolution. This thesis presents the development and application of a new in situ method for localized detection and genotyping of individual transcripts directly in cells and tissues. The described technique utilizes padlock probes and target-primed rolling circle amplification and is highly suitable for sensitive in situ analysis. First, a new strategy for directed cleavage of single stranded DNA was investigated, e.g. nucleic acid targets with extended 3´ ends, for successful initiation of rolling circle amplification. The presented cleavage strategy is simple and applicable for subsequent enzymatic reactions, e.g. ligation and polymerization. Specific cleavage of long target overhangs was demonstrated in synthetic oligonucleotides and in genomic DNA and the detection efficiency was substantially increased. For multiplex detection and genotyping of individual transcripts in single cells, a new in situ method was developed. The technique showed a satisfactorily detection efficiency and was later applied as a general mutation analysis tool for detection of KRAS point mutations in complex tumor tissue sections, e.g. formalin-fixed, paraffin-embedded tumor tissues and cytologic tumor imprints. Mutation status was assessed in patient samples by in situ padlock probe detection and results were confirmed by DNA-sequencing.  Finally, the method was adapted for simultaneous detection of individual mRNA molecules and endogenous protein modifications in single cells using padlock probes and in situ PLA. This assay will be useful for gene expression analysis and exploration of new drugs with vague effector sites. To our knowledge, no other technique exists today that offers in situ transcript detection with single-nucleotide resolution in heterogeneous tissues. The method will especially be suitable for discrimination of highly similar transcripts, e.g. splice variants, SNPs and point mutations, within gene expression studies and for cancer diagnostics.
456

Study of the Quasielastic {sup 3}He(e,e{prime}p) Reaction at Q{sup 2}=1.5 (GeV/c){sup 2} up to Missing Momenta of 1 GeV/c

Marat Rvachev January 2003 (has links)
Thesis (Ph.D.); Submitted to Massachusetts Inst. of Tech., Cambridge, MA (US); 1 Sep 2003. / Published through the Information Bridge: DOE Scientific and Technical Information. "JLAB-PHY-03-167" "DOE/ER/40150-2745" Marat Rvachev. 09/01/2003. Report is also available in paper and microfiche from NTIS.
457

Searching for Short Range Correlations Using (e,e'NN) Reactions

Bin Zhang January 2003 (has links)
Thesis; Thesis information not provided; 1 Feb 2003. / Published through the Information Bridge: DOE Scientific and Technical Information. "JLAB-PHY-03-38" "DOE/ER/40150-2762" Bin Zhang. 02/01/2003. Report is also available in paper and microfiche from NTIS.
458

An investigation of the feasibility of a method for measuring thermal neutron absorption cross sections using the AGN-201 reactor

Jenkins, George J Richter, Herbert B. January 1965 (has links) (PDF)
Thesis (M.S. in Physics)--Naval Postgraduate School, January 1965. / Thesis Advisor(s): Handle, Harry E. "January 1965." Description based on title screen as viewed on June 2, 2010 DTIC Descriptor(s): (Neutron Cross Sections, Thermal Neutrons), (Research Reactors, Reactor Feasibility Studies), Fast Neutrons, Gold, Radioactive Isotopes, Measurement, Perturbation Theory, Neutron Capture, Indium, Standards, Errors, Materials, Neutron Flux, Mathematical Analysis, Cadmium, Reactor Shielding Materials, Computer Programming, Foils (Materials), Reactor Control, Reactor Kinetics, Reactor Start Up Sources. DTIC Identifier(s): AGN-201 Reactors Includes bibliographical references (p. 32). Also available in print.
459

Determinacao experimental do potencial nucleo-nucleo e da densidade do projetil sup(18)O, por meio do espalhamento quase-elastico em nucleos-alvos na camada f-p

ROSSI JUNIOR, ERNESTO S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:45:29Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:01Z (GMT). No. of bitstreams: 1 07295.pdf: 6617875 bytes, checksum: 02bc676c5e25a80397e40d7d6eecf61d (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
460

What makes news on the front page? : an investigation of conceptions of newsworthiness in the East African Standard

Nzioka, Roseleen M 19 June 2013 (has links)
Determining what is newsworthy is a daily challenge even to the very people who source news, produce and disseminate it. This study is part an exposition and exploration of the different approaches that media researchers have used to explain and determine the value of news. Like similar research before it, this study more specifically delves into the news selection process of news of one particular newspaper with the goal of investigating why and how news is selected for publication in the front page. News is the 'result of many forces: ranging from source power, journalistic orientation, medium-preference and market model, news values and production routines and processes. The study briefly expounds on the different definitions of news as perceived in terms of the developed and developing world. Just as journalists do not operate in a vacuum, a close examination of the various definitions reveals that news cannot be defined in isolation. Its definition is intrinsically tied to that of news values. Also explored here are debates about news values and their Western rootedness. Here reference is made to literature regarding theories on the social construction of meanings and on the gatekeeping concept.The study is informed by similar research in gatekeeping studies and sociology of news studies. It is important to state at the outset that the study is not concerned with how news is produced but why there is a bias for certain kinds of news. I am interested in explaining why and how the writers and editors at the East African Standard make decisions about what is worthy of being published on the front page of the newspaper. This distinction is necessary because the theories that inform this study transcend news sourcing and production. This study takes cognizance ofthe fact that one cannot separate social processes from the individual and vice versa. For this reason, this study investigates and analyses the biases of individual gatekeepers at the East African Standard as well as their collective biases. In the concluding section, this study calls for an alternative paradigm for journalism and news. The foregoing discussions in the other sections prove that a universal definition of news and what is newsworthy will not suffice and there is need to contexualise it.

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