bluuebunny/crossref_metadata_2025_split huggingface dataset:
Feasibility of ultra‐short echo time (UTE) magnetic resonance imaging for identification of carious lesions
Authors: Bracher Anna‐Katinka , Hofmann Christian , Bornstedt Axel , Boujraf Saïd , Hell Erich , Ulrici Johannes , Spahr Axel , Haller Bernd , Rasche Volker 
Published: March 2011

AbstractThe objective of this study was to investigate the potential of ultra short echo time imaging for the assessment of caries lesions and early demineralization. 12 patients with suspected caries lesions underwent a dental magnetic resonance imaging investigation comprising ultra short echo time imaging (echo time = 50 μs) and spin echo imaging. Before the dental magnetic resonance imaging, all patients underwent a conventional clinical dental investigation including visual assessment of the teeth as well as dental x‐ray imaging. All lesions identifiable in the x‐ray could be clearly identified in the ultra short echo time images, but only about 19% of the lesions were visible in the spin echo images. In 19% of all lesions, the lesions could be more clearly delineated in the ultra short echo time images than in the x‐ray images. This was especially the case for secondary lesions. In direct comparison with the x‐ray images, all lesions appeared substantially larger in the dental magnetic resonance imaging data. The presented data provide evidence that caries lesions can be identified in ultra short echo time magnetic resonance imaging with high sensitivity. The apparent larger volume of the lesions in dental magnetic resonance imaging may be attributed to fluid accumulation in demineralized areas without substantial breakdown of mineral structures. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Phase enhancement for time‐of‐flight and flow‐sensitive black‐blood MR angiography
Authors: Kimura Tokunori , Ikedo Masato , Takemoto Shuhei 
Published: March 2011

AbstractA magnitude‐based MR angiography method of standard time‐of‐flight (TOF) employing a three‐dimensional gradient‐echo sequence with flow rephasing is widely used. A recently proposed flow‐sensitive black‐blood (FSBB) method combining three‐dimensional gradient‐echo sequence with a flow‐dephasing gradient and a hybrid technique, called hybrid of opposite‐contrast, allow depiction of smaller blood vessels than does standard TOF. To further enhance imaging of smaller vessels, a new enhancement technique combining phase with magnitude is proposed. Both TOF and FSBB pulse sequences were used with only 0th‐order gradient moment nulling, and suitable dephasing gradients were added to increase the phase shift introduced mainly by flow. Magnitude‐based vessel‐to‐background contrast‐to‐noise ratios in TOF and FSBB were further enhanced to increase the dynamic range between positive and negative signals through the use of cosine‐function‐based filters for white‐ and black‐blood imaging. The proposed phase‐enhancement processing both improved visualization of slow‐flow vessels in the brains of volunteer subjects with shorter echo time in TOF, FSBB, and hybrid of opposite‐contrast and reduced wraparound artifacts with smaller b values without sacrificing vessel‐to‐background contrast in FSBB. This method of enhancement processing has excellent potential to become clinically useful. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
A molecular MRI probe to detect treatment of cardiac apoptosis in vivo
Authors: Dash Rajesh , Chung Jaehoon , Chan Trevor , Yamada Mayumi , Barral Joëlle , Nishimura Dwight , Yang Phillip C. , Simpson Paul C. 
Published: March 2011

AbstractCell death by apoptosis is critical in myocardial diseases, and noninvasive detection of early, reversible apoptosis might be useful clinically. Exogenous Annexin‐V (ANX) protein binds membrane phosphatidylserine, which is externalized in early apoptosis. A molecular MRI probe was constructed with superparamagnetic iron oxide (SPIO) conjugated to recombinant human ANX (ANX‐SPIO). Apoptosis was induced with doxorubicin, a cardiotoxic cancer drug, in culture in neonatal rat ventricular myocytes, cardiac fibroblasts, and mesenchymal stem cells, and in vivo in the mouse heart. ANX‐SPIO was validated using T2*‐weighted 3T MRI. ANX‐SPIO produced T2* signal loss, reflecting iron content, that correlated highly with independent apoptosis markers; bound with high affinity to apoptotic myocytes by competition assay (Ki 69 nM); detected apoptosis in culture much earlier than did TUNEL stain; and revealed fibroblast resistance to apoptosis. With apoptosis in vivo, ANX‐SPIO produced diffuse myocardial T2* signal loss that correlated with increased iron stain and caspase activity. Treatment with an alpha‐1‐adrenergic agonist in vivo reversed apoptosis and eliminated the ANX‐SPIO MRI signal. It is concluded that cardiac MRI of ANX‐SPIO detects early, nonischemic cardiac apoptosis in culture and in vivo, and can identify reversibly injured cardiac cells in diseased hearts, when treatment is still possible. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
A new approach for vertical impedance in radially inhomogeneous soil layer
Authors: Wang K. H. , Yang D. Y. , Zhang Z. Q. , Leo Chin Jian 
Published: March 2011

SUMMARYIn the past studies on pile vibrations, the soil around the pile is mainly regarded as homogeneous or multi‐layered piecewise homogeneous. However, under most engineering conditions, the surrounding soil becomes seriously disturbed due to construction effects. This may strengthen or weaken the shear modulus of the soil resulting in the soil becoming radially inhomogeneous. As a consequence of this, El Naggar extended Novak's plane‐strain model to account for the radial inhomogeneity by the use of multiple springs connected in series. Rather than using this approach, this paper proposes a new model which is thought to be theoretically more rigorous and one which may be described as complex stiffness transfer model. It is shown that the solution developed in this study agrees well with the more limited solutions of Novak and Dotson and Veletsos under several special conditions. Finally, the scope of application has been enlarged as a result of the generalizations made in the present model. Copyright © 2011 John Wiley & Sons, Ltd.
OLEDs für Display‐ und Beleuchtungsanwendungen
Authors: Murano Sven 
Published: March 2011

AbstractDurch kontinuierliche technologische Verbesserungen haben organische Leuchtdioden (OLEDs) mittlerweile ein Niveau erreicht, das eine starke Penetration der Display‐ und Beleuchtungsmärkte in den nächsten Jahren erwarten lässt. OLEDs werden insbesondere für Anwendungen als Lichtquellen zur Beleuchtung oder Beschilderung zu völlig neuartigen Konzepten führen.
Licht im Kampf gegen Krebs und andere Volkskrankheiten
Authors: Jürgens Marion , Popp Jürgen 
Published: March 2011

AbstractOptische Technologien werden immer wichtigere Werkzeuge für Lebenswissenschaften und Medizin. Weltweit sind orschungsaktivitäten im Gang, die zum eil durch hoch dotierte öffentliche Förderprogramme unterstützt werden. Auch die Bundesregierung setzt weiter auf die Biophotonik: Seit dem vergangenen Jahr unterstützt sie acht neue Forschungsprojekte. Damit erhöht sich das Gesamtvolumen der öffentlichen und privaten Investitionen im Forschungsschwerpunkt Biophotonik auf rund 90 Millionen Euro.
Optisch‐elektrische Hybridkabel
Authors: Schramm Volker 
Published: March 2011

AbstractDie technologischen Vorteile beim Einsatz von optisch‐elektrischen Hybridkabeln sind offensichtlich: Der Verbindungsaufwand zwischen den Einsatzstandorten wird minimiert. Leistung und Meßdaten werden in einem Kabel übertragen. Die Verbindung ist bewegungsfähiger. Die Verwendung nur eines Kabels ermöglicht eine größere Packungsdichte. Die produktions‐ und ingenieurstechnische Lieferleistung wird durch nur einen Hersteller für nur ein Kabel erbracht. Der Anwender hat dadurch einen geringeren Koordinationsund Kostenaufwand.
Ein Strahl — Eine Matrix
Authors: Herdt Barbara , Bril Moshe 
Published: March 2011

AbstractDiffraktive optische Elemente (DOEs) werden genutzt, um mittels Vielstrahlinterferenz an periodischen Strukturen Lichtstrahlen zu formen. Am häufigsten werden sie zur Strahlprofiländerung (Beam Shaping), zur Korrektur von Abbildungsfehlern und zur Strahlteilung (Beam Sampling) eingesetzt. Ihre Vorteile dabei: einfache Handhabung, geringste Justage und geringe Anforderungen an den Eingangsstrahl.
Excellent Prospects for Europe
Authors: Wilkens Markus , Schellberg Florence 
Published: March 2011

AbstractA recently published study predicts surpassing growth rates for the Photonics sector. Photonics world market expected to reach 439 billion Euros in 2015. Revenues of European companies in Photonics climbed by 12 % to 49 billion Euros from 2005 to 2006.
EUVL — Extreme Ultraviolet Lithography
Authors: Kaiser Winfried , Kürz Peter 
Published: March 2011

AbstractDo you remember your first cell phone? And what you could do with it? Exactly: make phone calls. It has only been 10 years. And today? Cell phones have mutated into multifunction devices: now you can make phone calls, send text messages, take and send pictures, surf the Internet, listen to MP3s, play games, navigate and even watch movies. Essentially, cell phones tell the success story of the chip industry like no other technical instrument: even more power in an even smaller space at — comparably — even lower prices. It is the increasing power of microchips that influence the development of cell phones.Optical lithography is a key driver of this success story. In many aspects it is playing a key role in the manufacture of semiconductors. After all, every microchip is produced using the lithography process. Depending on its complexity, it must undergo this process several dozen times. At the same time, it is primarily the advances in optical lithography that enable the continuously rising integration density of microchips. Mammoth efforts are allowing the semiconductor industry and its suppliers to introduce a new technology today, EUV lithography (EUVL), which will continue to drive progress over the next decade through miniaturization. This article deals with the perspectives of EUVL and the challenges of the technology, and reviews its development.
Innovative Beam Guide Systems
Authors: Frank Dieter W. 
Published: March 2011

AbstractIn recent years, the use of lasers in all fields of endeavour has exploded. Laser producers are conquering new market niches with specialized equipment designed to fit the needs of their clients. The output produced by industrial lasers has increased greatly in recent years. Lasers can cut, mark or weld with a power of 10 kW and more. Unfortunately, the transfer of laser energy from the laser to the target still presents great difficulties. Adequate beam guides to direct the laser energy are often not available. Tailor made beam guide solutions are boosting efficiency and reliability in applying lasers to real‐world solutions.
Optical Design of Beam Delivery and Beam Forming Systems
Authors: Eppich Bernd 
Published: March 2011

AbstractThe layout of beam delivery and/or beam forming optical systems is a recurring task in development and application of laser systems and necessarily requires adequate simulation tools. Accurate and precise simulation of the propagation of laser beams through optical systems, with the aim of predicting the beam profile at desired locations, is challenging. It requires detailed characterization of the initial beam and application of sophisticated software, which usually can only be operated by highly qualified personal. Relaxing the requirements to the prediction of more general beam parameters like beam diameter, beam divergence, and Rayleigh length, important layout jobs can be accomplished by ease‐to‐use simulation tools based on a few beam parameters measured according to the well‐known ISO 11146 standard.
Titan‐Saphir Laser
Authors: Frowein Helmut 
Published: March 2011

AbstractIn den letzten 20 Jahren hat sich der Titan‐Saphir Laser zum Arbeitspferd der Spektroskopie und in vielen anderen Bereichen der Forschung entwickelt. Aus den Versuchsaufbauten der achtziger Jahre sind inzwischen stabile Systeme geworden, heute kann man Turn‐Key‐Systeme kaufen mit Pulsenergien von wenigen Nanojoule bis fast in den Joulebereich. Ti:Sa steht für Terawattlaser genauso wie für ultrapräzise Metrologie. Mit der Stabilität der Laser hat sich auch die Zahl der Anwendungen vergrößert, und die Entwicklung ist noch lange nicht am Ende.
Europäische Bildverarbeitungs‐Industrie weiter auf Wachstumskurs
Authors: Schwarzkopf Patrick 
Published: March 2011

AbstractDie industrielle Bildverarbeitung (IBV) ist längst zu einem Synonym für Wettbewerbsfähigkeit, hohe Qualität und Kosteneffizienz in der industriellen Produktion geworden. Aber auch außerhalb der Fabrik erobert sich diese universell einsetzbare Technologie schnell neue Märkte — in der Verkehrstechnik, im Labor, im Sicherheitsbereich oder als Bestandteil des Automobils. Dementsprechend positiv entwickeln sich derzeit die Zahlen im Bereich IBV.
Glänzend gelöst
Authors: Schmidgall Thomas 
Published: March 2011

AbstractIn der modernen Qualitätssicherung sind industrielle Bildverarbeitungssysteme ein unentbehrlicher Helfer. Sie sorgen für eine schnelle Qualitätsprüfung und Fehlerdetektion im laufenden Fertigungsprozess. Bei der Kontrolle von glänzenden Oberflächen stieß die automatisierte Bildverarbeitung bisher an ihre Grenzen. Hier ist das Erkennen von Einschlüssen, Textur‐ oder Farbabweichungen immer noch stichprobenartig dem menschlichen Auge vorbehalten. Ein neues Prüfverfahren ermöglicht jetzt die 100 % in‐process Prüfung von glänzenden und spiegelnden Teilen.
Von der strukturierten Faser zum Faserlaser
Authors: Reichel Volker , Schuster Kay , Kobelke Jens , Kirchhoff Johannes , Bartelt Hartmut 
Published: March 2011

AbstractFaserlaser sind kompakt, langlebig und haben eine ausgezeichnete Strahlqualität. Deshalb finden Faserlaser verschiedenster Ausgangsleistungen zunehmendes Interesse in der Mikrobeschriftung, Mikromaterialbearbeitung und in der Automobilindustrie. In diesem Artikel sollen neben den Anwendungsmöglichkeiten dieser neuartigen Lichtquellen vor allem auch die erforderlichen Technologien zur Herstellung von strukturierten und laseraktiven Fasern vorgestellt werden.
Neue optische Beschichtungen
Authors: Ehlers Henrik , Lappschies Marc , Beermann Nils , Ristau Detlev 
Published: March 2011

AbstractGegenwärtig gilt das Ionenstrahl‐Zerstäuben (Ion Beam Sputtering, IBS) als das Beschichtungsverfahren der Wahl, wenn im Bereich der optischen Beschichtungen höchste Qualitätsansprüche erfüllt werden müssen. In jüngster Zeit konnte das IBS‐Verfahren durch Kombination mit neuen Prozesskontrolltechniken und Materialmischtechniken für die Herstellung von Rugate‐Filtern mit kontinuierlichen Brechungsindexverläufen in seiner Anwendungsbreite noch einmal deutlich gesteigert werden.
Messen mit Subpixel‐Genauigkeit: Legende und Wirklichkeit
Authors: Schuster Norbert 
Published: March 2011

AbstractDie 2‐D‐Messtechnik mit elektronischen Bildaufnehmern hat sich zu einer Schlüsseltechnologie der Automatisierung entwickelt. Dabei hat die Frage nach der erreichbaren Genauigkeit oberste Priorität. Sie entscheidet über die Wahl der Kamera, der Abbildungsoptik und der Beleuchtung.
Metrology under Control
Authors: Kozma Ida Z. , Holzwarth Ronald , Sizmann Andreas , Mei Michael 
Published: March 2011

AbstractMode‐locked femtosecond lasers enable ultra precise measurements based on fundamental constants. Although in terms of pulse properties the performance of the state‐of‐the‐art Ti:sapphire lasers are yet superior to alternative ultrafast laser technologies, it is the fiber laser technology that facilitates the development of breakthrough applications outside the laboratory environment. Reliability and robustness of fiber lasers are attractive features for industry, while the unique SWaP factor (size, weight and power) designates the fiber‐based optical frequency combs a promising enabling technology even for space science.
Terahertz with Electronic Delay
Authors: Posthumus Jan 
Published: March 2011

AbstractTerahertz radiation has recently captured the imagination of many researchers and visionaries alike. Today, the most advanced means of terahertz spectroscopy are based on femtosecond lasers. Meanwhile the advantages of ultrafast fiber lasers are widely recognised. The newly introduced ECOPS technique makes another step forward by removing the need for mechanical delay stages.
Ultrafast Laser Supports Bio‐Imaging Applications
Authors: Ziegs Werner 
Published: March 2011

AbstractA wide range of bio‐imaging methods have evolved using ultrafast lasers, including numerous variants on multiphoton fluorescence excitation microscopy (MPE) and other types of non‐linear optical effects. Laser manufacturers have supported these cutting edge imaging techniques with a variety of new laser tools and accessories. This article reviews recent developments in ultrafast lasers and examines some research that exploits their performance.
Silicon‐based Photonics
Authors: Iannone Eugenio 
Published: March 2011

AbstractThe phenomenal increase in the amount of traffic generated by new video‐based telecommunications services such as IPTV is rapidly pushing optical transmission equipment towards higher bandwidth and a high quality of service. This trend demands a radical change in the cost model for optical telecommunications systems. It is no longer acceptable to provide high cost, low volume “jewels” — future development must be towards high volume, low cost commodities that can be more widely implemented throughout the network. One answer to this demand is the development of silicon‐nanophotonics.
Interview mit Theodor W. Hänsch
Authors: Wengenmayr Roland 
Published: March 2011

Abstract2005 erhielt Theodor W. Hänsch den Nobelpreis für Physik [1]. Der Direktor am MPI für Quantenoptik und Professor an der LMU München wird damit für seine Beiträge zur Laser‐Präzisionsspektroskopie gewürdigt, besonders für die Entwicklung des optischen Frequenzkamms. Außerdem verliehen ihm die Deutsche Physikalische Gesellschaft und die Gesellschaft Deutscher Chemiker den diesjährigen Otto‐Hahn‐Preis. Roland Wengenmayr sprach mit ihm über seinen Lebensweg als Forscher und seine aktuelle Arbeit.
Das perfekte Paar
Authors: Reeb Winfried 
Published: March 2011

AbstractIn der optoelektronischen Messtechnik spielt die optimale Abstimmung zwischen Emitter und Detektor die entscheidende Rolle für den reibungsfreien Betrieb von Systemen. Schon bei der Entwicklung ist darauf zu achten, dass bestimmte Bauteile anwendungsspezifisch angepasst werden.
Improved microwave absorption and electrostatic charge dissipation efficiencies of conducting polymer grafted fabrics prepared via in situ polymerization
Authors: Saini Parveen , Choudhary Veena , Dhawan Sundeep. K. 
Published: March 2011

AbstractPolyaniline (PANI) and polypyrrole (PPY) were grafted over cotton fabrics by in situ polymerization. FTIR spectra show systematic shifting of bands corroborating surface grafting of conducting polymers on cotton fabric. SEM images revealed that the surface coating of PANI was smoother than PPY. However, better control over coating thickness and uniformity was achieved in PPY fabric. The probable formation mechanism of grated fabrics has also been proposed. The good thermal stability and acceptable electronic conductivity values indicate that these fabrics could be used for electrostatic charge dissipation and microwave absorption. The antistatic studies have shown complete charge dissipation (decay time <0.01 sec). The microwave absorption studies of the conducting fabrics in X‐band (8.2–12.4 GHz) show absorption dominated total shielding effectiveness in the range −11.3 to −11.7 dB (>92% attenuation) and −9.2 to −9.6 dB (>88% attenuation) for fabrics grafted with PPY and PANI, respectively. Copyright © 2011 John Wiley & Sons, Ltd.
Characterization and antibacterial activity of chitosan‐based composites with polyester
Authors: Wu Chin‐San 
Published: March 2011

AbstractThe effects of replacing poly(butylene succinate adipate) (PBSA) with acrylic acid‐grafted PBSA (PBSA‐g‐AA) on the structure and the properties of a PBSA/chitosan composite were investigated. The properties of both PBSA‐g‐AA/chitosan and PBSA/chitosan were compared using Fourier transform infrared (FTIR), 13C nuclear magnetic resonance (NMR), X‐ray diffraction (XRD), and an antibacterial activity test. With PBSA‐g‐AA in the composite, the compatibility with chitosan and, consequently, the properties of the composite became greatly improved due to the formation of ester and imide groups that conferred better dispersion and homogeneity of chitosan in the matrix. Composites containing PBSA‐g‐AA/chitosan exhibited superior mechanical properties due to greater compatibility between the two components. Moreover, chitosan enhanced the antibacterial activity of the composites. Composites of PBSA‐g‐AA or PBSA that contain chitosan have better antibacterial activity. The functionalized PBSA‐g‐AA/chitosan composites showed markedly enhanced antibacterial properties due to the carboxyl groups of acrylic acid, which acted as coordination sites for the chitosan phase, allowing the formation of stronger chemical bonds. Copyright © 2011 John Wiley & Sons, Ltd.
Homo‐ and copolymerization of norbornene and 5‐norbornene‐2‐yl acetate with bis‐(β‐ketonaphthylamino)palladium(II)/B(C6F5)3 catalytic system
Authors: Huang Ran , He Xiaohui , Chen Yiwang , Nie Huarong , Zhou Weihua 
Published: March 2011

AbstractThe polymerization of norbornene with bis(β‐ketonaphthylamino) palladium(II), Pd{CH3C(O)CHC[N(naphthyl)]CH3}2, in combination with tris(pentafluorophenyl)borane (B(C6F5)3), was investigated by varying the B:Pd(II) molar ratio, monomer concentration, reaction temperature, and time. The catalytic activity was found to reach 2.8 × 104 gPolymer/(molPd•h) and the obtained polynorbornene (PNBE) was confirmed to be vinyl addition polymer and showed good thermo‐stability (Tdec > 350°C), but exhibited poor solubility in organic solvents due to the relative higher stereo regularity. Pd{CH3C(O)CHC[N(naphthyl)]CH3}2/B(C6F5)3 system is also an active catalyst for copolymerization of norbornene and 5‐norbornene‐2‐yl acetate (NBE‐OCOCH3) in toluene with moderate yields (in 9.2–36.5% yields) and produces the addition‐type copolymer with relatively high molecular weights (0.96 × 104–2.13 × 104 g/mol). The incorporation of functional group in the copolymer can be controlled up to 0.9–23.5 mol% by varying the NBE‐OCOCH3 monomer feed ratios from 10 to 90%. The copolymers are proved to be noncrystalline and show good solubility in common organic solvents and excellent thermal stability up to 350°C. Copyright © 2011 John Wiley & Sons, Ltd.
Preparation, characterization, and properties of polyamic acid nano‐emulsion
Authors: Ding Fuchuan , Tong Yuejin , Luo Xiaolan , Guan Huaimin , Hu Binghuan 
Published: March 2011

AbstractA facile method was developed to prepare polyamic acid (PAA) nano‐emulsion using a non‐aqueous emulsification. The resultant PAA nano‐emulsion was characterized by light‐scattering particle size analysis, transmission electron microscopy (TEM), zeta potential, and conductivity analyses. It was found that polyamic acid salt (PAS), formed by partially neutralizing PAA at the carboxylic groups using triethyl amine (TEA), was of great importance for nano‐emulsification. The effect factors on the formation of PAA nano‐emulsion were investigated. To get a stable PAA nano‐emulsion in methanol (precipitant), the following ratios are required: amine/COOH (molar ratio) = 0.6–0.7, precipitant/solvent (mass ratio) = 1.5–2.25. A PAA nano‐emulsion with droplets ranging in size from 50 to 100 nm was obtained under optimized conditions. The driving force for the formation of PAA nano‐emulsion was also discussed. Copyright © 2011 John Wiley & Sons, Ltd.