bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electronic Excitation Energy Migration in a Photonic Dye–Zeolite Antenna
Authors: Yatskou Mikalai M. , Meyer Marc , Huber Stefan , Pfenniger Michel , Calzaferri Gion 
Published: June 2004

AbstractElectronic excitation energy migration in a photonic antenna host–guest material has been investigated by time‐resolved fluorescence experiments and by Monte Carlo calculations. The host consists of a linear channel system (zeolite L). The channels are filled with energy transporting dyes (donors) in their middle section and by one or several monolayers of a strongly luminescent trapping dye (acceptors) at each end of the channels. Excitation energy is transported among the donors in a series of steps until it reaches an acceptor at one end of the channels, or it is somehow trapped on its way, or it escapes by spontaneous emission. We describe the organization of dyes in the channels by means of Monte Carlo simulation and we report time‐resolved data on a variety of pyronine‐, oxonine‐, and oxonine,pyronine–zeolite L materials. In the latter, the pyronine acts as donor and oxonine as acceptor. We find that the luminescence decay of crystals containing only one kind of dye is single exponential for moderate loading if measured under oxygen‐free conditions, but biexponential otherwise. The main characteristic of the time evolution of oxonine,pyronine–zeolite L crystals is that the acceptor intensity is first built up before it starts to decay. This intensity increase becomes faster with increasing donor loading, a fact that beautifully supports the interpretation that the crystals behave as photonic antenna in which excitation energy is transported preferentially along the channels by a Förster‐type mechanism until it reaches the acceptor, where it is emitted as red luminescence.
Synthesis and Characterization of Tris(β‐ketoiminato)ruthenium(III) Complexes: Potential Precursors for CVD of Ru and RuO2 Thin Films
Authors: Chou T.‐Y. , Lai Y.‐H. , Chen Y.‐L. , Chi Y. , Prasad K.R. , Carty A.J. , Peng S.‐M. , Lee G.‐H. 
Published: June 2004

AbstractThe synthesis and characterization of RuIII metal complexes [Ru(keim1)3] (1) and [Ru(keim2)3] (2) are reported, where (keim)H is an abbreviation for the fluorinated ketoimine ligands with formula HOC(CF3)=CHCR=NMe; (keim1)H with R = Me and (keim2)H with R = CF3. These newly synthesized complexes were characterized by spectroscopic methods, while the second complex, 2, was further examined by single‐crystal X‐ray diffraction (XRD), revealing an octahedral coordination for the Ru cation, with three ketoiminate arranged in a mer‐configuration, a consequence of the enhanced steric interaction between ligands. Moreover, both Ru metal complexes show good volatility and thermal stability. CVD experiments were conducted using these complexes at temperatures of 325–450 °C. The Ru metal and RuO2 thin films on silicon wafers were successfully obtained using either a mixture of 2 % O2 in argon or pure O2 as the carrier gas, respectively. Our result shows that a 2 % O2 concentration induces the formation of Ru metal, while that only complex 1 gives formation of a columnar RuO2 phase upon switching to pure O2 as the CVD carrier gas. Scanning electron microscopy (SEM) images were taken to reveal surface morphologies, while X‐ray photoelectron spectroscopy (XPS) and XRD were utilized to access their atomic composition as well as the intrinsic packing of the as‐deposited thin film materials.
Proliferative response of bystander cells adjacent to cells with incorporated radioactivity
Authors: Gerashchenko Bogdan I. , Howell Roger W. 
Published: June 2004

AbstractBackgroundIn a recent study, we showed that cells irradiated with γ‐rays stimulate cell growth of unirradiated (bystander) cells, when the two populations are co‐cultured as a mixture (Cytometry 2003;54A:1–7). Direct cell‐to‐cell contact appears to be a prerequisite for the proliferative response of the bystander cells (Cytometry, 2003 56A:71–80). The aim of the current work is to investigate the possible proliferative bystander effects caused by intracellular irradiation with incorporated radionuclides, specifically the short‐range β particle emitter, tritium (3H).MethodsSubconfluent monolayers of rat liver epithelial cells (WB‐F344) were incubated in the presence of (methyl‐3H)thymidine (3HTdR) at concentrations ranging between 5.2 kBq/ml and 57.8 kBq/ml for 18 h. Radiolabeled cells, containing between 0.7 × 10−3 Bq/cell and 8.8 × 10−3 Bq/cell were mixed with unlabeled (i.e., bystander) cells in a ratio of 1:1 and cultured together for 24 h followed by an flow cytometry (FCM) study of their proliferation. In order to discriminate the two populations of co‐cultured cells, one cell population (unlabeled bystander cells) was stained with carboxyfluorescein diacetate, succinimidyl ester (CFDA SE), which metabolizes intracellularly. The absorbed doses received by the radiolabeled cells that contained 0.7 × 10−3, 2.5 × 10−3, and 8.8 × 10−3 Bq/cell were 0.14, 0.49, and 1.7 Gy, respectively.ResultsCells that were not treated with tritiated thymidine (unlabeled cells), in the presence of radiolabeled cells that received absorbed doses from 0.14–1.7 Gy, showed enhanced cell growth by approximately 9 to 10%.ConclusionsCells labeled with 3HTdR can induce increased proliferation in neighboring unlabeled bystander cells. FCM provides an excellent basis for characterization of proliferative bystander effects in co‐culture systems. © 2004 Wiley‐Liss, Inc.
Automated counting of mammalian cell colonies by means of a flat bed scanner and image processing
Authors: Dahle Jostein , Kakar Manish , Steen Harald B. , Kaalhus Olav 
Published: June 2004

AbstractBackgroundClonogenic assays are used frequently to measure the cell killing and mutagenic effects of radiation and other agents. Clonogenic assays carried out manually are tedious and time‐consuming and involve a significant element of subjectivity. However, several commercial automatic colony counters are available. Based on CCD video imaging and image analysis they are relatively expensive and can analyze only one petri dish at a time.MethodWe have developed a cheaper and more efficient device, which employs a flat bed scanner to image 12 60‐mm petri dishes at a time. Two major problems in automated colony counting are the clustering of colonies and edge effects. By using standard image analysis and implementing an inflection point algorithm, these problems were greatly diminished. The resulting system was compared with two manual colony counts, as well as with automated counts with the Oxford Optronix ColCount colony counter for cell lines V79 and HaCaT.ResultsComparisons assuming the manual counts to be correct showed that our automatic counter was slightly more accurate than the commercial unit.ConclusionsAs a whole, our automated colony counter performed significantly better than the commercial unit with regard to processing time, cost and accuracy. © 2004 Wiley‐Liss, Inc.
Chromatic shifts in the fluorescence emitted by murine thymocytes stained with Hoechst 33342
Authors: Petersen Timothy W. , Ibrahim Sherrif F. , Diercks Alan H. , van den Engh Ger 
Published: June 2004

AbstractBackgroundMany methods in flow cytometry rely on staining DNA with a fluorescent dye to gauge DNA content. From the relative intensity of the fluorescence signature, one can then infer position in cell cycle, amount of DNA (i.e., for sperm selection), or, as in the case of flow karyotyping, to distinguish individual chromosomes. This work examines the staining of murine thymocytes with a common DNA dye, Hoechst 33342, to investigate nonlinearities in the florescence intensity as well as chromatic shifts.MethodsMurine thymocytes were stained with Hoechst 33342 and measured in a flow cytometer at two fluorescence emission bands. In other measurements, cells were stained at different dye concentrations, and then centrifuged. The supernatant was then used for a second round of staining to test the amount of dye uptake. Finally, to test for resonant energy transfer, we measured fluorescence anisotropy at two different wavelengths.ResultsThe fluorescence of cells stained with Hoechst 33342 is a nonlinear process that shows an overall decrease in intensity with increased dye uptake, and spectral shift to the red. Along with the spectral shift of the fluorescence to the longer wavelengths, we document decreases in the fluorescence anisotropy that may indicate resonant energy transfer.ConclusionsAt low concentrations, Hoechst 33342 binds to the minor groove of DNA and shows an increase in fluorescence and a blue shift upon binding. At higher concentrations, at which the dye molecules can no longer bind without overlapping, the blue fluorescence decreases and the red fluorescence increases until there is approximately one dye molecule per DNA base pair. The ratio of the blue fluorescence to the red fluorescence is an accurate indicator of the cellular dye concentration. © 2004 Wiley‐Liss, Inc.
Use of SYBR14, 7‐amino‐actinomycin D, and JC‐1 in assessing sperm damage from rats with spinal cord injury
Authors: Nunez Rafael , Murphy Thomas F. , Huang Hosea F. , Barton Beverly E. 
Published: June 2004

AbstractBackgroundAlthough fluorescent dyes combined with flow cytometry have been used to confirm the viability of sperm in the past, methods to detect damage to spermatozoa following injury have been limited to use of dyes, which are often difficult to adequately compensate for in a single laser system.MethodsIn this article, we present what we believe is a better method to assess damage to sperm secondary to spinal cord injury in an in vivo model, for use with a standard Ar laser and flow cell. In this rat model of spinal cord injury leading to sperm damage, the spinal cords of the rats were injured, but the reproductive organs were not. To understand the origins of sperm injury, and to develop ways to overcome the loss of fertility, we used the viability dye SYBR‐14 along with 7‐amino actinomycin D to detect apoptosis. Additionally, we used the dye JC‐1 to measure the changes in mitochondrial transmembrane potential that accompany the damage.ResultsWe found that SYBR‐14 plus 7‐amino actinomycin D was a useful method for quantifying apoptosis, particularly when another dye, such as JC‐1, was used simultaneously. By using these dyes in concert with motility studies, we were able to quantify the extent of damage to sperm and correlate it to the decrease in motility of sperm (r2 = 0.99 for SYBR14 versus motility and r2 = 0.98 for JC‐1 versus motility by regression analysis).ConclusionsWith a method established to measure injury to sperm, we hope to determine which treatment regimens of ones we will test are effective in restoring sperm to a more fertile state, in the future. © 2004 Wiley‐Liss, Inc.
“Cellular astronomy”—A foreseeable future in cytometry
Authors: Shapiro Howard M. 
Published: June 2004

AbstractAdvances in electro‐optic technology within the past 2 years, notably the development of high‐intensity light‐emitting diodes and highly efficient charge‐coupled device cameras, have made it feasible to produce small, simple, rugged, automated fluorescence image cytometers, with selling prices well below US $10,000, that can make measurements previously the exclusive domain of flow and scanning cytometers costing many times more. It should be feasible to apply the new cytometric technology in scientific and geographic areas for which a previous generation of instruments was too complex and too expensive, e.g., to problems of diagnosis and management of infectious diseases prevalent at critical levels in resource‐poor areas, such as the human immunodeficiency virus, malaria, and tuberculosis. © 2004 Wiley‐Liss, Inc.
Biegebemessung von bewehrtem Mauerwerk nach dem ω‐Verfahren auf der Grundlage realer Spannungs‐Dehnungs‐Beziehungen
Authors: Mertzsch Olaf 
Published: June 2004

AbstractDie Tragfähigkeit von bewehrtem Mauerwerk ist in starkem Maße von der Art des verwendeten Mauerwerks abhängig. Dabei wirken sich nicht nur die Festigkeit, sondern auch das Spannungs‐Dehnungs‐Verhalten auf die Tragfähigkeit aus. In /1/ wurde das Spannungs‐Dehnungs‐Verhalten von Mauerwerk untersucht. Die für die weiteren Betrachtungen wesentlichen Ergebnisse sind in Tabelle 1 zusammengestellt. Ein Vergleich dieser Ergebnisse mit den in /2/ und /3/ zugrunde gelegten Ansätzen zeigt, daß hier das reale Dehnungsverhalten nur unzureichend berücksichtigt wird. Aus diesem Grund wurden Berechnungshilfsmittel erarbeitet, mit deren Hilfe das Verformungsverhalten des verwendeten Mauerwerks wirklichkeitsnah berücksichtigt werden kann. Ein Vergleich der maximalen Tragfähigkeit zeigt deutliche Unterschiede, die bei einer Bemessung nach /2/ und /3/ nicht ausreichend berücksichtigt werden.
Zur Biegebemessung von bewehrtem Mauerwerk nach Eurocode 6
Authors: Jäger Wolfram , Baier Gunar 
Published: June 2004

AbstractIm Rahmen der Überarbeitung des EC 6, Teil 1‐1 in der Fassung der ENV 1996‐1‐1 /1/ erfolgte eine Überprüfung wesentlicher Teile der Passagen zum bewehrtem Mauerwerk /2/. Die Ergebnisse bildeten die Grundlage für die deutsche Stellungnahme. Das Ziel dabei war vorrangig, Sicherheitsrisiken bei der Bemessung von bewehrtem Mauerwerk auszuschließen und eine Modifikation der Bemessungsregeln zu erreichen.Als ein wesentliches Ergebnis konnte das bisher enthaltene, aus dem British Standard stammende Verfahren zur Biegebemessung von bewehrtem Mauerwerk an die besonderen Eigenschaften der in Deutschland vorzugsweise eingesetzten Stein‐Mörtel‐Kombinationen angepaßt und in die Schlußfassung des Eurocode 6, prEN 1996‐1‐1: 2003‐03 /3/ eingebracht werden. Weitere Themenstellungen, wie z. B. Schubbeanspruchung sowie Bemessung von stabilitätsgefährdeten bewehrten Mauerwerksbauteilen, wurden ebenfalls untersucht. Der nachfolgende Beitrag beschränkt sich auf die Darstellung der Grundlagen der Biegebemessung nach EC 6 und die Berücksichtigung der heute in Deutschland üblichen Mauerwerkarten.
Untersuchungen zur Schubtragfähigkeit von Ziegelmauerwerk
Authors: Roßbach Michael , Schmidt Ulf , Schubert Peter 
Published: June 2004

AbstractDurch Einwirkung von Wind und auch Erdbeben werden Mauerwerkwände in der Wandebene auf Schub (Scheibenschub) beansprucht. Der Nachweis ausreichender Schubtragfähigkeit erfolgt nach DIN 1053‐1 für Mauerwerk aus genormten Steinen und Mauermörteln bzw. nach entsprechenden allgemeinen bauaufsichtlichen Zulassungen. Aus der bisherigen Auswertung von Schubversuchen an Mauerwerk ergeben sich teilweise erhebliche Festigkeitsreserven. Die nachfolgend beschriebenen theoretischen und experimentellen Untersuchungen sollen dazu beitragen, die bisherigen Untersuchungsergebnisse zu ergänzen und abzusichern und den Erkenntnisstand zur rechnerischen Bestimmung der Schubtragfähigkeit von Mauerwerk zu verbessern — insbesondere in Hinblick auf die derzeitige Überarbeitung von DIN 1053‐1.
Bauausführung der Hauptkuppel
Authors: Spiegel Frank , Uhlmann Thomas 
Published: June 2004

AbstractIm Juni 1996 wurden von der Niederlassung Dresden der Walter Bau AG vereinigt mit Dywidag als Federführender in Arbeitsgemeinschaften die Arbeiten zum archäologischen Wiederaufbau der Frauenkirche aufgenommen. Beim Mauerwerksbau aus Sandstein waren dabei in Einheit die hohen ästhetischen Anforderungen der Gestaltung als auch die weit über dem Üblichen liegenden ingenieurmäßigen Vorgaben für das Mauerwerk zu bewältigen. Die Errichtung der zweischaligen Hauptkuppel begann unter Nutzung aller bis dahin gesammelten Erfahrungen im Juni 2002 und wurde am 23. Mai 2003 mit dem Setzen des Schlußsteins vollendet.
Das Lehrgerüst der Hauptkuppel
Authors: Noack Mario 
Published: June 2004

AbstractBei der Konstruktion des Lehrgerüstes für die Hauptkuppel flossen die Besonderheiten des Bauwerks und die Erfahrungen aus vorangegangenen Lehrgerüstkonstruktionen an der Frauenkirche ein.Da die Tragwirkung der einzelnen Mauerwerksschichten erst nach Ringschluß und Erreichen der notwendigen Festigkeit des Mörtels entsteht, mußte das Mauerwerk bis dahin unterstützt werden. Die begrenzte Tragfähigkeit der Stützkonstruktion der Lehrschalung machte eine schrittweise Entlastung bereits fertiggestellter Abschnitte der Kuppel erforderlich.Das auf Schalungs‐ und Gerüstbau spezialisierte Ingenieurbüro Noack war mit der Planung des Lehrgerüstes der Kuppel beauftragt.
Mäßige Vorspannung des Kuppelmauerwerks
Authors: Stoll Volker , Dornacher Siegfried 
Published: June 2004

AbstractBei rotationssymmetrischen Kuppeln, die aus Kreisbogenabschnitten erzeugt werden, entstehen unterhalb der oberen Bruchfuge Ringzugkräfte, so auch bei der Kuppel der Frauenkirche. Da Mauerwerk diese nicht oder nur begrenzt aufnehmen kann, müssen umlaufende Anker eingelegt werden. Die Notwendigkeit dazu erkannte intuitiv George Bähr bereits beim Bau der Kuppel (Bild 1).Beim Wiederaufbau wurden insgesamt sechs robuste Anker aus hochfesten Breitflachstählen in geometrischer Anlehnung an das historische Vorbild in den Mauerwerksverband der Kuppel integriert. Um ihre sofortige Wirksamkeit und damit die Dichtheit der Kuppel zu gewährleisten, wurden sie mäßig vorgespannt. Der Beitrag stellt die gewählte Lösung dar und erläutert deren Ausführung.
Die Laterne als krönender Abschluß
Authors: Jäger Wolfram , Stoll Volker 
Published: June 2004

AbstractDer obere Abschluß des Steinbaus der Frauenkirche wird wie bei vielen anderen Kirchen von einer Laterne gebildet. Filigran krönt sie das Kirchbauwerk. Die Laterne trägt das hölzerne Laternendach und das Turmkreuz. Gemeinsam mit diesen beiden Bauteilen weist sie mit ca. 30 m eine Höhe auf, die eine baurechtliche Einordnung als Hochhaus erfordern würde.
Detection of high‐risk human papillomavirus (HPV) DNA by Hybrid Capture II in women referred due to atypical glandular cells in the primary screening
Authors: Oliveira Eliane R.Z.M. , Derchain Sophie F.M. , Rabelo‐Santos Silvia H. , Westin Maria Cristina A. , Zeferino Luiz Carlos , Campos Elisabete A. , Syrjanen Kari J. 
Published: June 2004

AbstractWe assessed the detection of high‐risk human papillomavirus DNA (HPV‐DNA) in women examined by a second Pap smear due to atypical glandular cells (AGC) detected in their screening Pap smear. In 91 women included in the study, a second Pap smear was taken and HPV‐DNA test was performed using Hybrid Capture II (HC II). The second Pap smear showed no abnormalities in 28 (31%) cases, ACG in 17 (19%) cases, and high‐grade squamous intraepithelial lesions (HSIL) or worse in 24 (26%). HC II test was positive in 36% of the cases. Considering the second Pap smear diagnosis, HPV‐DNA was detected in 87% of the women with HSIL, 100% of women with in situ adenocarcinoma, and only in 11% of the women with no abnormalities. The use of the second Pap smear combined with HPV‐DNA may improve the management of women with AGC in the primary screening. Diagn. Cytopathol. 2004;31:19–22. © 2004 Wiley‐Liss, Inc.
Novel tyramide‐based tyrosinase assay for the detection of melanoma cells in cytological preparations
Authors: Angeletti Cesar , Khomitch Vitali , Halaban Ruth , Rimm David L. 
Published: June 2004

AbstractFine‐needle aspiration (FNA) has been used as a fast, minimally invasive, and reliable method for the evaluation of enlarged lymph nodes. However, there are some cases where the definitive diagnosis cannot be elicited with morphology alone, especially cases without a known primary lesion. Although immunocytochemical studies may be helpful in some situations, they are often complicated by nonspecific staining. Recently, a novel tyramide‐based tyrosinase assay was developed. Since melanocytes, both benign and malignant, produce tyrosinase, we postulated that this assay could be useful as an in situ biochemical diagnostic test. We modified the Perkin Elmer TSA assay, a commercial assay based on tyramide, a tyrosine analog that is a substrate for tyrosinase, for use on air‐dried cytological preparations. We validated the assay on cell lines, then tested a small series of melanoma and nonmelanoma cytology specimens. The YUGEN8 melanoma cell line was used to optimize the assay and it showed abundant reaction product, while HeLa cells served as a negative control. All melanoma cytology specimens were positive and all nonmelanoma specimens were negative. These results suggest that this simple, fast, and inexpensive assay is a sensitive and specific method for detection of melanoma cells in cytology specimens. This method may be a useful ancillary procedure for the resolution of challenging melanoma cases. Diagn. Cytopathol. 2004;31:33–37. © 2004 Wiley‐Liss, Inc.
Atypical teratoid/rhabdoid tumor: Cytology and differential diagnosis in adults
Authors: Raisanen Jack , Hatanpaa Kimmo J. , Mickey Bruce E. , White Charles L. 
Published: June 2004

AbstractAtypical teratoid/rhabdoid tumors (AT/RTs) are malignant intracranial neoplasms that usually occur in the posterior fossa of children. They are characterized by cells with paranuclear rhabdoid inclusions, a mesenchymal and epithelial immunohistochemical profile, and 22q deletions with inactivation of the INI1/hSNF5 gene. Although they usually occur in young children, AT/RTs are being recognized in adults with increasing frequency. We report the cytologic features of an AT/RT from the cerebellum of a 45‐year‐old man and discuss the differential diagnosis in adults. Diagn. Cytopathol. 2004;31:60–63. © 2004 Wiley‐Liss, Inc.
Metastatic bronchioloalveolar carcinoma presenting as a solitary thyroid nodule: Report of a case with fine‐needle aspiration cytopathology
Authors: Parwani Anil V. , Erozan Yener S. , Ali Syed Z. 
Published: June 2004

AbstractAlthough cancers metastatic to the thyroid are frequently mentioned in autopsy studies, such a finding is quite rare in routine clinical practice. Metastatic non‐small‐cell carcinomas to the thyroid may present a diagnostic dilemma, particularly when they share morphological similarities with primary thyroid tumors. Herein, we report a case of metastatic bronchioloalveolar carcinoma that presented as an isolated left thyroid nodule in a 68‐year‐old woman. The aspirates were cellular and showed numerous papillary‐like tissue fragments, elongated nuclei with prominent nuclear grooves, frequent mitoses, and psammoma bodies. The latter features raised the possibility of papillary thyroid carcinoma. However, also seen were three‐dimensional tumor nests and acinar‐forming fragments. Immunostains (positive for cytokeratin‐7 and carcinoembryonic antigen and negative for cytokeratin‐20 and thyroglobulin) confirmed the metastatic nature of the carcinoma. In a patient with known primary neoplasm, the differential diagnosis of a thyroid nodule should always include a metastatic lesion along with primary neoplasia. Diagn. Cytopathol. 2004;31:43–47. © 2004 Wiley‐Liss, Inc.