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1

Regenbögen in Raum und Zeit: Ultrakurze Laserpulse  

NASA Astrophysics Data System (ADS)

Fortschritte auf dem Gebiet der Ultrakurzpulslaser stellen an Forschung und Technik neue Herausforderungen hinsichtlich Formung und Diagnostik komplexer Lichtfelder. Für die Kontrolle der zeitlichen und räumlichen Spektraleigenschaften werden neuartige Optiken entwickelt. Spiegel aus Mehrfachschichten mit trickreichem Design gestatten optimale Pulskompression. Mit verbesserter SPIDER-Technik werden kürzeste Femtosekundenpulse messbar. Dispersionsarme Dünnschicht-Mikrooptiken erlauben eine Analyse von Wellenpaketen in Raum und Zeit. Mit derartigen Komponenten können auch optische Riesenwellen, so genannte X-Pulse, erzeugt werden.

Grunwald, Rüdiger; Steinmeyer, Günter

2004-09-01

2

Variabilität des Reviergesangs des Buchfinken (Fringilla coelebs) zur Raum-Zeit-Beschreibung von Metapopulationen  

NASA Astrophysics Data System (ADS)

Der Buchfinkengesang wurde in Potsdam in zwei Hauptpopulationen über drei Jahre aufgenommen. Jedes Individuum wurde eindeutig am individuellen Strophentypenrepertoire identifiziert. Ein weiterer Punkt der die individuelle Wiedererkennung bestätigt ist die hohe Standorttreue der adulten Männchen. Die beschriebene Methode eignet sich für die Untersuchung von gesamten Populationen, um den Wandel des Gesangs von Populationen in Raum und Zeit zu beschreiben. Die Haupterkenntnisse der Arbeit sind: - Die Gesamtanzahl der Grundstrophentypen innerhalb einer Population bleibt über Jahre konstant. - Die relative Häufigkeit jedes einzelnen Strophentyps variiert von Jahr zu Jahr und von Population zu Population. - Gesangslernen erfolgt exakt mit einem Korrektheitsgrad von mindestens 96%. - Das Song-Sharing ist innerhalb der Population hoch. Die diskutierten Mechanismen für das Song-Sharing sind: Die Lebenserwartung, das Zugverhalten, das Lernverhalten, die Etabliertheit von Strophentypen, Weibchenpräferenzen und die Reaktionen der territorialen Männchen. - Weiterhin wurde ein Modell zur kulturellen Evolution des Buchfinkengesangs programmiert, um die Rolle der Einflussfaktoren, wie Fehlerquote, Abwanderungsrate und Laufzeit zu ermitteln. Der Wandel des Dialektes erfolgt graduell in Raum und Zeit. Daher sind keine scharfen Dialektgrenzen anzutreffen. Trotz dieser Tatsache markieren die etablierten Strophentypen die Population. 50 % der Juvenilen siedeln am Geburtsort, auf diese Weise bleibt der Dialekt erhalten und Inzest wird vermieden. -Analysiert man das Repertoire benachbarten Männchen bei isolierten Alleen, so entspricht die Gesangsangleichung in etwa dem Zufall. -Intraindividuelle Vergleiche der quantitativen Parameter des jeweiligen Strophentyps wurden saisonal und annuell durchgeführt. Saisonal konnten für einen Strophentyp ein Trend ermittelt werden. Bei jährlichen Vergleichen konnten intraindividuell ausschließlich nicht signifikante Ergebnisse ermittelt werden, wohingegen die interindividuelle Variation in zwei Fällen signifikant war. In einem Fall bestand ein Trend und in einem weiteren Fall war die Variationsunterschiede nicht signifikant. - Der Verlauf der Brutsaison lässt sich an der jährlichen Gesangsaktivität nachvollziehen. Chaffinch song was recorded in Potsdam in two major populations of chaffinches over a period of three years. Each male was identified unambiguously because of their individual song type repertoires. These are usually easy to distinguish from sonagrams as the variation is discontinuous. A further point for individual recognition is the fixed territorial behaviour of adult males. The described method is employed to examine whole populations and to observe changes with space and time in the song of a population. The major findings of the study are: - The total amount of basic song types in each population is constant over years. - The quantity of each basic song type is different and varies from year to year and from population to population. - Song copying is extremely accurate on at least 96% of occasions. - Song-type sharing is high within populations. Discussed mechanisms for song neighbourhoods are: expectation of life, semi-migratory behaviour, learning skills, establishment of song types, female choice and male vs male interaction. Furthermore a model of cultural evolution of chaffinch song was programmed to determine the role of factors like error rate, rate of emigration and running time. The changes are gradual in space and time. Hence the dialect borders are smooth. Despite this fact established song types mark the population. As every second juvenile bird settles in the population of his birth inbreeding is avoided and the dialect structure is retained. - Analysing the repertoires of neighbouring males (“next door neighbours”) in isolated avenues to examine mutual influences suggests that these have the same amount of song types in common than would be expected by chance. - Within intraindividual comparisons the quantitative parameters of the same son

Nolte, Björn

2003-10-01

3

Die Orientierungsfunktionen eines affinen Raumes  

Microsoft Academic Search

Der Begriff der Orientierung, der in der Topologie eine wichtig~ Rolle spielt, wird meist auch in tier Geometrie so erkl~rt, wie es in der Topologie fiblich ist [26]: Man nimmt eine Testfigur (,,Indikatrix\\

Erich Glock

1962-01-01

4

Der freie Raum synchroner Chlorella  

Microsoft Academic Search

The free space in the cell wall of Chlorella fusca has been determined by a dilution method with 14C-mannitol. Owing to a Donnan effect, 36Cl-perchlorate is less suitable, 14C-dextran was used to correct for external water. During the light phase (16 h) of the generation cycle, the free space decreases from 11 to 4% of the cell volume. It increases

H. W. Tromballa; E. Broda

1972-01-01

5

The Politics of Language in Education: The "Mikro" Case in South Africa  

ERIC Educational Resources Information Center

School language policies stand at the nexus of identity politics and human rights in contemporary South Africa. Since 1996, litigation on school language policies has been resolved on the basis of language rights. Courts have emphasized that the mere mention of single-medium schools in the constitution in no way privileges these institutions over…

Bargueno, David P.

2012-01-01

6

Evaluation of Satellite Image Lineament Patterns in Raume Baden-Frick-Laufenburg-Zurzach.  

National Technical Information Service (NTIS)

Satellite images often show a dense network of linear elements. The effective meaning of these lineament patterns is still under discussion, especially as to their significance in structural interpretations. In northern Switzerland, a detailed comparison ...

A. Isler

1984-01-01

7

Wirksamkeit von Anthelminthika gegenüber Pferdestrongyliden im Raum Salzburg und erste Ergebnisse der selektiven Behandlung  

Microsoft Academic Search

\\u000a Summary  In recent years more and more cases of anthelmintic resistant equine strongyles were reported. The latest developments are\\u000a cases of resistance against macrocylic lactones. In order to delay this process less anthelmintics and only those which have\\u000a been previously tested for their efficacy on each individual farm should be used. During the grazing season 2008 faecal samples\\u000a of 281 horses

Anne M. Becher; Kurt Pfister

2010-01-01

8

Zur Kinematik Weylscher Raum-Zeit-Modelle (Kinematic Weyl Space-Time Models).  

National Technical Information Service (NTIS)

This model is based on the axiomatics of Ehlers and Pirani, which use the Lorentz signature (plus-plus-plus-minus). A field equation of the gravitation does not appear from a kinematic point of view. Mathematical propositions are proved in the following c...

V. Perlick

1989-01-01

9

Industrial Evolution and Revolution in the Cislunar Space, 1980 - 2010 Industrielle Evolution und Revolution im Geolunaren Raum 1980-2010.  

National Technical Information Service (NTIS)

The industrial evolution and revolution in geolunar space after 1900 is discussed. Topics include industrial ecology of the open world, growth by extraterrestrial industrialization, and space industry. Energy supply from space, notably electricity generat...

K. A. Ehricke

1973-01-01

10

Topologische Raum Aller Extremalpunkte Einer Kompakten Konvexen Menge (Topological Space of All Extremum Points of a Compact Convex Set).  

National Technical Information Service (NTIS)

The topological space of the extremum points of a completely metric convex set was investigated. The fundamentals and results of the Choquet theory are presented. Contributions to the theory of (semi-)standard Choquet simplex are given. The theory of the ...

D. Bensimon

1987-01-01

11

Die Wirkung als Naturkraft und die Herkunft von Zeit, Raum, Dimensionen, Naturkräften, und Gesetzen von Logik, Geometrie und Physik bei der Entstehung der Welt  

NASA Astrophysics Data System (ADS)

Das Wirkungs-Welt-Modell enthält eine einfache Beschreibung des Anfanges der Welt, wonach, ausgehend vom einfachsten Zustand der logisch notwendigen Bejahung ihrer Existenz innerhalb ihr selbst, alles sukzessiv bewirkt wird, und ihre logischen, geometrischen und physikalischen Eigenschaften Aspekte der Verkörperung und Fortwirkung primordialer Fakten darstellen, ohne externe Schöpfung auszuschließen. Die ersten Dimensionen und sie formal und subjektiv charakterisierenden Größen sind: Informationsmenge und Wirkung, mit abzählbarem Ereignis und Wirkungsquantum; Zeit und Energie, mit deren Planck-Einheiten; Geschwindigkeit oder Strecke und Impuls, mit Lichtgeschwindigkeit oder Planck-Länge; Krümmung oder zwei räumliche Richtungen, mit Gravitationskonstanten, und aus den ihnen entsprechenden primären Naturkräften setzen sich die uns geläufigen zusammen.

Landgraf, Werner

2011-02-01

12

Two mechanisms of vision in primates  

Microsoft Academic Search

Versuche an „split-brain“ Affen legten die Annahme nahe, daß die Wahrnehmung des Raumes und die Wahrnehmung der Identität von Gegenständen auf anatomisch getrennten Hirnmechanismen beruhen. In der vorliegenden Arbeit werden die Sehmechanismen des Gehirns untersucht, wobei von der Überlegung ausgegangen wird, daß hier zwei parallele Prozesse involviert sind: ein dezentrierter („ambient“), der die Wahrnehmung des den Körper umgebenden Raumes bestimmt,

Colwyn B. Trevarthen

1968-01-01

13

Snells Identifikatie van Pathogene Mikro-Organismen in de Lucht m.b.v. Specifieke IgE-antisera, Gekoppeld aan Mestcellen (Rapid Identification of Pathogenic Micro-Organisms in the Air Using Specific IgE-antisers Coupled to Mast Cells).  

National Technical Information Service (NTIS)

The aim of this study was to investigate the feasibility of an immunological method for rapid identification of microorganisms, based on the principle of the immediate type (= type I) hypersensitivity reaction, i.e. the interaction of mast cells, specific...

D. A. Schoonenwolf J. L. F. Gerbrandy

1983-01-01

14

Remotely controlled CODAR continuously observed surface currents in the German Bay  

Microsoft Academic Search

An experiment to continuously measure surface currents in the Helgolander Bucht (German Bay) during two months in the winter 1987-8 is described. Modified CODAR radars were set up 45 km apart on the islands of Helgoland and Wangerooge. Both stations were remotely computer controlled while the data flow of the stations was made possible by telephone links to a Mikro

T. Schlick; K.-W. Gurgel; H.-H. Essen; F. Schirmer

1990-01-01

15

Measurement of Intraocular Pressure from the ExtraOcular Space of the Eye using a MEMS Pressure Sensor  

Microsoft Academic Search

Intraocular pressure measurements are recorded in porcine eyes that have been surgically modified. The vitreous pressure is manipulated by an external connection to a fluidic reservoir and measured directly by a Millar mikro-tip catheter. Indirect vitreous pressure is measured with a Freescale medical grade pressure sensor at the choroid surface, within a scleral recess, and at the sclera surface. Results

Matthew Turner; John Naber; Kevin Walsh

2008-01-01

16

75 FR 4423 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Portland Cement...  

Federal Register 2010, 2011, 2012, 2013

...the National Cooperative Research and Production Act of 1993--Portland Cement Association...the National Cooperative Research and Production Act of 1993, 15 U.S.C. 4301 et...Chemicals, Inc., Allentown, PA; LWB Refractories, York, PA; MikroPul,...

2010-01-27

18

Agentenbasierte Modelle in der Soziologie  

Microsoft Academic Search

\\u000a Dieser Beitrag zielt darauf ab zu illustrieren, wie agentenbasiertes Modellieren für die Integration von Theorie und Empirie\\u000a bei mechanismenbasierten Erklärungen hilfreich sein kann. Unser Ausgangspunkt ist, dass die Erforschung der MikroGrundlagen\\u000a sozialer Resultate der wichtigste Stützpfeiler bei Untersuchungen in der Analytischen Soziologie ist. Wenn Makro-Resultate\\u000a auf Handlungen, Motivationen und Interaktionen von Individuen zurückgeführt werden, kann die Soziologie weit informativere\\u000a Erklärungen

Riccardo Boero; Flaminio Squazzoni

19

The influence of orthoses on the proprioception of the ankle joint  

Microsoft Academic Search

The ankle joints of 14 healthy volunteers and 16 patients with unstable ankle joints were tested regarding their functional and proprioceptive capabilities. All of them were active athletes. Three tests were used of the study: single-leg stance test, single-leg jumping course test, angle-reproduction test. The influence of three stabilization devices (lace-on-brace\\/“Mikros”, stirrup-brace\\/ “Aircast”, taping) on the proprioceptivity of stable and

J. Jerosch; I. Hoffstetter; H. Bork; M. Bischof

1995-01-01

20

Left ventricular dysfunction after open repair of simple congenital heart defects in infants and children: Quantitation with the use of a conductance catheter immediately after bypass  

Microsoft Academic Search

Objective: Quantification of myocardial injury after the simplest pediatric operations by load-independent indices of left ventricular function, using conductance and Mikro-Tip pressure catheters (Millar Instruments, Inc., Houston, Tex.) inserted through the left ventricular apex. Methods: Sixteen infants and children with intact ventricular septum undergoing cardiac operations had left ventricular function measured, immediately before and after bypass. Real-time pressure-volume loops were

Rajiv R. Chaturvedi; Christopher Lincoln; John W. W. Gothard; Michael H. Scallan; Paul A. White; Andrew N. Redington; Darryl F. Shore

1998-01-01

21

Strahlentherapie von gutartigen Erkrankungen: eine Bestandsaufnahme für Deutschland  

Microsoft Academic Search

Hintergrund: Der Einsatz der Strahlentherapie bei gutartigen Erkrankungen wird kontrovers diskutiert und zum Teil kaum noch praktiziert, zum Beispiel im angloamerikanischen Raum. In anderen Teilen der Welt, besonders Zentral- und Osteuropa, wird die Strahlentherapie routinemäßig eingesetzt. Analog zur European Society of Therapeutic Radiology and Oncology (ESTRO) wurde eine systematische Analyse zum Stand der Radiotherapie bei gutartigen Erkrankungen in Deutschland durchgeführt.

M. Heinrich Seegenschmiedt; Alexander Katalinic; Hans-Bruno Makoski; Wulf Haase; Günther Gademann; Eckhard Hassenstein

1999-01-01

22

Paul Parin \\/ Fritz Morgenthaler \\/ Goldy Parin-Matthèy: Die Weißen denken zuviel  

Microsoft Academic Search

Der Ausdruck „Ethnopsychoanalyse“ wurde erstmals von Georges Devereux bei seinen theoretischen Bemühungen verwendet, eine\\u000a kulturübergreifende Psychiatrie und Psychotherapie zu konzipieren. Im deutschsprachigen Raum ist der Begriff mit den psychoanalytischen\\u000a Untersuchungen der Zürcher Psychoanalytiker Paul Parin, Goldy Parin-Matthèy und Fritz Morgenthaler verbunden.

Johannes Reichmayr

23

Didaktik Anfassen erwünscht - Science Center unter der Lupe  

NASA Astrophysics Data System (ADS)

In den letzten Jahren gab es einen wahren Boom von Neugründungen so genannter Science Center. Sie sollen die Naturwissenschaften insbesondere die Physik für einen breiten Personenkreis erfahr- und lernbar machen. In loser Folge werden wir einige dieser Center im deutschsprachigen Raum vorstellen. Der vorliegende einführende Beitrag gibt eine kurze Übersicht über Konzepte, Anliegen und Trends dieser Einrichtungen.

Schneider, Werner; Vollmer, Michael

2005-03-01

24

Partizipatives Gesundheitslernen in Organisationen  

Microsoft Academic Search

Zusammenfassung  Bei betrieblicher Gesundheitsförderung (BGF) werden partizipative Prozesse des Organisationalen Lernens (OL) als zentral angesehen.\\u000a Gesundheitszirkel stellen dazu im deutschsprachigen Raum, auch wegen der Unterstützung durch Krankenkassen, zentrale Instrumente\\u000a dar. Lernen, das durch Gesundheitszirkel angeregt wird, soll dabei nachhaltig sein, d.h die Lernkreisläufe sollen nicht unterbrochen\\u000a werden. Um diese Lernprozesse, insbesondere die Lernkreisläufe bei Gesundheitszirkel zu analysieren, wurden in der vorliegenden

Harald Stummer; Cäcilia Innreiter-Moser; Karoline Moldaschl; Martina Schaffenrath-Resi; Claudia Eitzinger

2008-01-01

25

Free energy by space quanta manipulation (RQM)  

Microsoft Academic Search

RQM-i.e. the Space (German: Raum)-Quanta-Manipulation stands for purposeful dilution resp. compression of the space quanta medium and the thereby resulting interactions with the matter contained within the influenced space volume. RQM aggregates-containing a system of electromagnets set in a specific geometric arrangement are capable of converting mechanical pressure differences within the space quanta medium (gravitational waves) into electric energy. The

Peter A. Gibas; Friedrich Greilinger; J.-M. Lehner; W. Rusterholz

1997-01-01

26

Über differenzierbare asymptotisch konvexe funktionenfamilien bei der nicht-linearen gleichmä?igen approximation  

Microsoft Academic Search

w 1. Eialeituag Den Begriff der asymptotischen Konvexit~t haben MEINARDUS und SCHWEDT [7, 8] in die Approximationstheorie eingeffihrt. Den Ausgangspunkt bildet dabei das folgende nicht-lineare Approximationsproblem: Sei M ein kompakter Hausdorff-Raum und C(M) der Vektorraum der stetigen reellwertigen Funktionen auf M, versehen mit der Maximum-Norm Ilgll =maxlg(x)l, g6C(M). xeM In den Anwendungen ist M gew6hnlich ein reeUes abgeschlossenes Intervall, eine

Werner Krabs; L. COLLATZ

1967-01-01

27

Strategien in der ambulaten Behandlung des Tinnitus  

Microsoft Academic Search

  \\u000a Beim chronischen Tinnitus ist dies mit der Einführung der Retrainingtherapie durch Jastreboff (1994, 1993, 1996) und Hazell (1994) in den angloamerikanischen\\u000a Staaten und durch Biesinger (1996) und Kellerhals (1996) im deutschsprachigen Raum gegeben.\\u000a \\u000a \\u000a \\u000a In Deutschland wird im Gegensatz zu den angloamerikanischen und vielen europäischen Ländern auch die Akutbehandlung des Tinnitus durchgeführt und wissenschaftlich untersucht. Die Leitlinien hierfür wurden von

E. Biesinger; C. Heiden; V. Greimel; T. Lendle; R. Höing; K. Albegger

1998-01-01

28

Spezielle Relativitätstheorie und die klassische Feldtheorie  

NASA Astrophysics Data System (ADS)

Der Autor vermittelt den Lesern in didaktisch eingängiger Weise wichtige Grundlagen des Gebietes ausgehend vom Relativitätsprinzip, der Lorentz-Transformation und deren physikalischen Folgen. Nach relativistischer Mechanik und kinetischer Theorie werden Elektro-, Hydro- und Thermodynamik als klassische Feldtheorien in relativistischem Gewand vorgestellt und Anwendungsbeispiele gegeben. Die Geometrie der Raum-Zeit, die Struktur von Lorentz- und Poincaré-Gruppe und ihrer Darstellungen werden ebenso besprochen wie klassische 1-Teilchen-Gleichungen (Klein-Gordon, Dirac) als Vorstufen zur Feldquantisierung.

Goenner, Hubert

29

Pacific coral reefs of panamá: Structure, distribution and predators  

Microsoft Academic Search

Zusammenfassung  Die rezenten Korallenriffstrukturen an der östlichen Pazifikküste von Panamá zeigen starkes Wachstum. Von den 20 vorhandenen Arten hermatypischer Coelenteraten gehören 3 zu der GattungMillepora, die erstmals im ostpazifischen Raum beobachtet wurde. Die häufigeren Scleractinia sindPocillopora (4 Arten),Pavona (6 Arten) undPorites (5 Arten).Pocillopora ist der wichtigste Gerüstbildner in Kuppen- und Saumriffen, während die massigen Kolonien vonPavona undPorites an der Basis der

Peter W. Glynn; Robert H. Stewart; John E. McCosker

1972-01-01

30

Segmental structure of alpha waves in sleep-deprived subjects  

Microsoft Academic Search

\\u000a Zusammenfassung\\u000a \\u000a Das Ziel der Forschung \\u000a   Die quasi-stationären Segmente des EEG-Signals können als zeitlich stabile lokale Mikro-Zustände der Gehirntätigkeit dargestellt\\u000a werden,wobei die Übergänge zwischen aufeinander folgenden Segmenten die relativ schnelle Änderung eines solchen Mikrozustandes\\u000a in den anderen bedeuten können. Die adaptive Segmentierung erlaubt es, die Übergangspunkte mit drastischen Änderungen der\\u000a Amplitude zu identifizieren und die EEG-Aufzeichnung in quasi-stationäre Segmente zu schneiden.Wir

Dmitriy A. Putilov; Evgeniy G. Verevkin; Olga G. Donskaya; Arcady A. Putilov

2007-01-01

31

Grundlagen  

NASA Astrophysics Data System (ADS)

Jede Form der auditiven Kommunikation durchläuft eine Übertragungskette. Im einfachsten Fall besteht sie aus einer Schallquelle, der Luft als akustischem Medium und einem Hörer. Bereits hier beeinflussen die Eigenschaften der Quelle, des Mediums, des umgebenden Raums und des Empfängers das Verständnis der übermittelten Nachricht auf charakteristische Weise. Jeder Musiker und jeder Schauspieler kann bestätigen, wie stark seine "Botschaft“ etwa von den Eigenschaften des Aufführungsraums beeinflusst wird. Selbst in dieser Alltagssituation wird die Kommunikation also durch ein Audiosystem vermittelt und durch dessen Eigenschaften spezifisch geprägt, erst recht natürlich bei der Übertragung durch technische, elektronische Medien.

Weinzierl, Stefan

32

Hermann Minkowski: From Geometry of Numbers to Physical Geometry  

NASA Astrophysics Data System (ADS)

For the historian or philosopher of science, Hermann Minkowski is known for the formulation of Special Relativity in terms of four-dimensional space-time. The original text is the famous 1908 "Raum und Zeit", but it is rarely mentioned that Minkowski is the author of a geometry of numbers "Geometrie der Zahlen", a most important work in number theory. In his arithmetic geometry, Minkowski introduces the notion of numerical grids or lattices (Zahlengitter) that are meant as a geometrical representation of arithmetical relations, that is isolated points and intersection points used to define the approximation of a real number by rational numbers.

Gauthier, Yvon

33

Basic principles for measurement of intramuscular pressure  

NASA Technical Reports Server (NTRS)

We review historical and methodological approaches to measurements of intramuscular pressure (IMP) in humans. These techniques provide valuable measures of muscle tone and activity as well as diagnostic criteria for evaluation of exertional compartment syndrome. Although the wick and catheter techniques provide accurate measurements of IMP at rest, their value for exercise studies and diagnosis of exertional compartment syndrome is limited because of low frequency response and hydrostatic (static and inertial) pressure artifacts. Presently, most information on diagnosis of exertional compartment syndromes during dynamic exercise is available using the Myopress catheter. However, future research and clinical diagnosis using IMP can be optimized by the use of a miniature transducer-tipped catheter such as the Millar Mikro-tip.

Hargens, A. R.; Ballard, R. E.

1995-01-01

34

Diagnosis of genital Chlamydia trachomatis infections in asymptomatic males by testing urine by PCR.  

PubMed

An enzyme-linked immunosorbent assay (EIA) (MikroTrak; Syva) was compared with PCR (Amplicor; Roche) for detection of Chlamydia trachomatis in first-void urine (FVU) from 184 men attending a skin and venereal disease clinic. The prevalence of C. trachomatis in the population studied was 18.5%. Discrepant results between Syva EIA and Roche PCR were retested by using major outer membrane protein primer-based PCR. After retesting, the sensitivity, the specificity, and the positive and negative predictive values for the Syva EIA were 85.3, 100, 100, and 77.5%, respectively, and those for the Roche PCR 100, 100, 100, and 100%, respectively. It was concluded that PCR provides a highly sensitive and specific noninvasive screening method for genital chlamydial infection in asymptomatic men. PMID:7814464

Domeika, M; Bassiri, M; Mårdh, P A

1994-10-01

35

Diagnosis of genital Chlamydia trachomatis infections in asymptomatic males by testing urine by PCR.  

PubMed Central

An enzyme-linked immunosorbent assay (EIA) (MikroTrak; Syva) was compared with PCR (Amplicor; Roche) for detection of Chlamydia trachomatis in first-void urine (FVU) from 184 men attending a skin and venereal disease clinic. The prevalence of C. trachomatis in the population studied was 18.5%. Discrepant results between Syva EIA and Roche PCR were retested by using major outer membrane protein primer-based PCR. After retesting, the sensitivity, the specificity, and the positive and negative predictive values for the Syva EIA were 85.3, 100, 100, and 77.5%, respectively, and those for the Roche PCR 100, 100, 100, and 100%, respectively. It was concluded that PCR provides a highly sensitive and specific noninvasive screening method for genital chlamydial infection in asymptomatic men.

Domeika, M; Bassiri, M; Mardh, P A

1994-01-01

36

Analyzing Real Vector Fields with Clifford Convolution and Clifford-Fourier Transform  

NASA Astrophysics Data System (ADS)

Postprocessing in computational fluid dynamics and processing of fluid flow measurements need robust methods that can deal with scalar and vector fields. While image processing of scalar data is a well-established discipline, there is a lack of similar methods for vector data. This paper surveys a particular approach defining convolution operators on vector fields using geometric algebra. This includes a corresponding Clifford-Fourier transform including a convolution theorem. Finally, a comparison is tried with related approaches for a Fourier transform of spatial vector or multivector data. In particular, we analyze the Fourier series based on quaternion holomorphic functions of Gürlebeck et al. (Funktionentheorie in der Ebene und im Raum, Birkhäuser, Basel, 2006), the quaternion Fourier transform of Hitzer (Proceedings of Function Theories in Higher Dimensions, 2006) and the biquaternion Fourier transform of Sangwine et al. (IEEE Trans. Signal Process. 56(4),1522-1531, 2007).

Reich, Wieland; Scheuermann, Gerik

37

Fehler begehen - Mathematik verstehen Über die Bedeutung von Fehlern für das Verstehen  

NASA Astrophysics Data System (ADS)

Auch wenn eine historisch oder systematisch umfassende Darstellung zur Fehlerthematik bislang nicht vorliegt, ist die Idee, einer Fehleranalyse unter der Leitfrage, welche Fehler von Schülerinnen und Schülern aufgrund welcher epistemologischen Überzeugungen begangen werden, zentralen Raum für die Betrachtung von Verstehensprozessen einzuräumen, nicht neu. So ist es geradezu ein Charakteristikum einer modernen konstruktivistischen Didaktik, die eigenen Fehler von Lernenden als ihre individuellen Lerngelegenheiten zu begreifen, die einen wichtigen Motor für den subjektiven Lernfortschritt bilden. Diese Sichtweise wurzelt aus psychologischer Perspektive in Analysen in der Tradition Piagets, der in Abkehr von einer quantitativen, psychometrischen Beschreibung kognitiver Prozesse, wie sie sich zum Beispiel in Intelligenztheorien nach Binet findet, qualitativ zu beschreiben versuchte, in welcher Weise Kinder und Jugendliche denken und urteilen. Doch auch schon in der klassischen Philosophie sind entsprechende Ansätze zu finden. Prominente Beispiele hierfür sind die Idolenlehre Bacons und die Ideenlehre Platons.

Käser, Udo

38

Chemical Speciation and Mobilization of Mercury and Methyl Mercury at Sub-anoxic Conditions in Wetlands and Sediments with Special Emphasis on Organic Thiols  

NASA Astrophysics Data System (ADS)

A correct description of the chemical speciation of Hg and MeHg is a prerequisite for understanding biogeochemical processes like retention-mobilization, methylation-demethylation and bioaccumulation. Binding affinity experiments and spectroscopic studies have clearly established that both inorganic Hg and methyl mercury (MeHg) are strongly complexed by reduced organic functional groups (thiols, RSH) in natural organic matter (NOM). Stability constants for Hg and MeHg associated to NOM macromolecules (humic substances) have been shown to be of a similar magnitude as Hg-thiol and MeHg-thiol associations in well-defined organic molecules like cysteine. As a consequence of this strong bonding, complexes with NOM will highly dominate the speciation of Hg and MeHg, both in the solid phase and in pore water, under oxidized conditions. This also holds for environments with concentrations of halides (Cl) in the mM range. Under anoxic conditions in soils and sediments, inorganic mono-, bi- and polysulfides will form complexes with Hg. At concentrations of dissolved inorganic sulfides exceeding 10 mikroM, Hg-sulfide complexes will dominate the speciation and the contribution from organic Hg-thiols will be less than 1%. However, at slightly reduced (sub-anoxic) conditions with inorganic sulfides in the 0.1-2 mikroM range, complexes with thiols, bi- and polysulfides will all contribute to the solubility of Hg. Crucial is whether elemental sulphur is formed or not. With elemental S present, Hg-polysulfides will outcompete all other species, including neutral Hg-sulfides available for methylating bacteria. Thus, as a basis for selection of relevant chemical speciation models, independent spectroscopic information about solid phases like S80(s) and HgS(s) (using sulfur XANES, Hg EXAFS etc) is crucial. The identity of some proposed Hg-sulfides and their stability constants (e.g. HOHgSH0 and HgS5OH- ), are still uncertain and their influence on the chemical speciation will be discussed. The importance of relevant models for the chemical speciation of MeHg is discussed in the context that changes in MeHg solubility in many studies erroneously are interpreted as a consequence of methylation-demethylation and transport processes.

Skyllberg, U.

2007-12-01

39

Fontinalis antipyretica as a bioindicator of environmental conditions in freshwater ecosystem from Sava River watershed and Cerkni?ko Lake, Slovenia  

NASA Astrophysics Data System (ADS)

Polluted waters recharging from agriculture water systems into watersheds have influence on water quality and living habitat. Stable isotopes of carbon and nitrogen in combination with other minor and trace elements are often used to trace biogeochemical processes and contamination of water systems. The aim of the study was to assess state of environment with minor and trace elements and stable isotopes of C and N in selected Slovenian streams. Ten locations in Notranjska region, Slovenia, with different land use in the catchment (town, village, agricultural areas, farms, dairy farms), including reference point considered as non-polluted site, were sampled. Samples of water and aquatic moss F. antipyretica in Slovenian fresh waters were taken in all four seasons during years 2010 and 2012, but for stable isotope analyses of C and N only in three seasons during years 2010 and 2011. The water chemistry of investigated locations is dominated by hydrogen carbonate - calcium - magnesium, concentrations of nitrate seasonally range from 2.07 mg/l to 6.4 mg/l and at reference site does not exceed 1.3 mg/l. Total alkalinity of water at investigated locations ranges from 2.9 to 6.02 mM. The pH of investigated water range from 7.2 to 8.5, waters are saturated with oxygen (up to 134%) and conductivity ranges from 295 to 525 mikroS/cm, while at reference site conductivity is up to 180 mikroS/cm. The content of minor and trace elements in F. antipyretica ranged for Ni 4-38 mikrog/g, Zn 17-105 mikrog/g, Pb 2-28 mikrog/g, Cd 220-1953 ng/g, Cu 4-27 mikrog/g, Cr 4-49 mikrog/g, As 1-6 mikrog/g and Se 0.33-3.24 mikrog/g. The most polluted watershed was Pšata stream (agricultural areas, cattle farm) with highest values for Ni, Cr, Pb, Zn and As. The highest content of Se, was found in village (dairy farms) in Žerovniš?ica stream. The highest values were measured in February and October. Isotopic composition of dissolved inorganic carbon seasonally range from -13.3 to -8.1‰, and indicate waters dominated by degradation of organic matter and dissolution of carbonates. At the reference point average measured isotopic composition of dissolved inorganic carbon value is -2.7‰ which confirmed that this is a non-polluted site. Isotopic composition of carbon of F. antipyretica seasonally ranges from -45 to -32.9‰ and isotopic composition of nitrogen from -0.2‰ to 6.5‰, respectively. In comparison to C3 terrestrial plants F. antipyretica has more negative isotopic composition of carbon value, which is probably related with the difference in CO2 plant fixation and depends on isotopic composition of dissolved inorganic carbon in water, which is primarily controlled by geological composition and soil thickness in the watershed. Higher isotopic composition of nitrogen value found in F. antipyretica is related to agricultural activity in watershed, while at the reference site measured isotopic composition of nitrogen value is -4.1 ‰. From our study it is evident that isotopic composition of carbon and nitrogen is useful tracer of natural and anthropogenic inputs from terrestrial (fertilizing, sewage sludge) to water system.

Kandu?, Tjaša; Mechora, Špela; Stibilj, Vekoslava

2014-05-01

40

Diagnose und Therapie einer Depression im h?heren Lebensalter - Einfl?sse von Patienten- und Arztmerkmalen  

PubMed Central

Zusammenfassung Studienergebnissee aus dem englischsprachigen Raum zeigen, dass diagnostische und therapeutische Entscheidungen von Hausärzten bei der Versorgung von depressiven Patienten systematischen Einflüssen unterliegen, und dass sowohl Merkmale des Arztes als auch des Patienten unabhängig vom Krankheitsbild Einfluss auf diese Entscheidungen haben. In der vorliegenden Arbeit werden Ergebnisse einer deutschen Studie präsentiert, in der die Einflüsse von Patienten- und Arztmerkmalen auf diagnostische und therapeutische ärztliche Entscheidungen bei einer Depression untersucht wurden. Unter Anwendung eines faktoriellen Experimentaldesigns spielten professionelle Schauspieler in Videofilmen die Rolle von Patienten, die Symptome für eine depressive Erkrankung äußern. In den Videofilmen, die alle auf einem identischen Skript basieren, wurden systematisch die Patientenmerkmale Alter (55 vs. 75 Jahre), Geschlecht und sozialer Status (Hausmeister vs. Lehrer) variiert. Die randomisierte Ärztestichprobe wurde nach dem Arztgeschlecht und professioneller Erfahrung (< 5 vs. > 15 Jahre) geschichtet. Der Videofilm wurde insgesamt 128 niedergelassenen Ärzten für Allgemeinmedizin und hausärztlich tätigen Internisten in ihrer Praxis vorgespielt. Danach wurden die Ärzte zu unterschiedlichen Aspekten von Diagnose und Therapie befragt. Es wurde erhoben, ob der Arzt dem Patienten über das gezeigte Gespräch hinausgehende Fragen stellen würde, welche Diagnosen er für wahrscheinlich hält, wie sicher er sich mit seiner Diagnose ist, welche diagnostischen Tests er anordnen würde, ob er den Patienten überweisen würde oder ob er Medikamente verordnen oder ihm Empfehlungen zur Änderung seines Lebensstils geben würde. Die Ergebnisse weisen darauf hin, dass sowohl die Diagnose als auch die Therapie einer Depression durch niedergelassene Hausärzte in Deutschland nur geringfügig durch die untersuchten Merkmale der Patienten und der behandelnden Ärzte beeinflusst wird.

von dem Knesebeck, Olaf; Bonte, Markus; Siegrist, Johannes; Marceau, Lisa; Link, Carol; McKinlay, John

2013-01-01

41

Vom Urknall zum Durchknall  

NASA Astrophysics Data System (ADS)

Lautstarker Applaus erhob sich im Salon III/IV des Marriott-Hotels von Crystal City im amerikanischen Bundesstaat Virginia. In dem überfüllten Konferenzraum starrten alle wie gebannt auf die Leinwand, wo nicht mehr zu sehen war als ein nüchternes Diagramm aus zahlreichen Punkten und einer geschwungenen Kurve. Nureine eigenartige Personengruppe konnte sich davon zu Emotionen hinreißen lassen - Physiker auf der Jahrestagung der Astronomischen Gesellschaft, die ihren Begeisterungssturm noch minutenlang fortsetzten. Was war geschehen? Die im Diagramm aufgetragenen Daten bestätigten mit einer nie da gewesenen Genauigkeit ein fundamentales Naturgesetz zur Wärmeabstrahlung von heißen Körpern. 1900 von Max Planck entdeckt, leuchtete es nun in geradezu mathematischer Reinheit auf. Noch sensationeller war der Ursprung der Daten - Mikrowellensignale verschiedener Frequenzen, die nicht aus einem irdischen Labor stammten, sondern von einem heißen Urzustand des Universums! Ein Feuerball aus Wasserstoff und Helium, noch ohne jegliche Strukturen, die irgendwann Leben ermöglichen sollten, ließ damals seinem Licht freien Lauf. Mehr als zehn Milliarden Jahre war es bis zu den Detektoren des vom Menschen gebauten Satelliten COBE unterwegs, der wenige Tage zuvor die Daten übertragen hatte. Wenn ich das alles wie einen Film in meiner Vorstellung ablaufen lasse, bekomme ich immer eine Gänsehaut, als würde ich die inzwischen extrem abgekühlte Strahlung tatsächlich spüren. Ihre Gleichverteilung im Raum macht uns auch deutlich, dass wir uns nicht einbilden dürfen, an einem besonderen Ort im Universum zu leben - intelligente Aliens könnten sich seitdem überall entwickelt haben! Sollten sie - was nicht wahrscheinlich ist - uns wirklich von Zeit zu Zeit über die Schulter schauen, dann hätten sie an jenem Nachmittag des 13. Januar 1990, als der Vortrag stattfand, bestimmt anerkennend mit ihrem großen Kopf genickt.

Unzicker, Alexander

42

Large effects on body mass index and insulin resistance of fat mass and obesity associated gene (FTO) variants in patients with polycystic ovary syndrome (PCOS)  

PubMed Central

Background The polycystic ovary syndrome (PCOS), a common endocrine disorder in women of child-bearing age, mainly characterised by chronic anovulation and hyperandrogenism, is often associated with insulin resistance (IR) and obesity. Its etiology and the role of IR and obesity in PCOS are not fully understood. We examined the influence of validated genetic variants conferring susceptibility to obesity and/or type 2 diabetes mellitus (T2DM) on metabolic and PCOS-specific traits in patients with PCOS. Methods We conducted an association study in 386 patients with PCOS (defined by the Rotterdam-criteria) using single nucleotide polymorphisms (SNPs) in or in proximity to the fat mass and obesity associated gene (FTO), insulin-induced gene-2 (INSIG2), transcription factor 7-like 2 gene (TCF7L2) and melanocortin 4 receptor gene (MC4R). To compare the effect of FTO obesity risk alleles on BMI in patients with PCOS to unselected females of the same age range we genotyped 1,971 females from the population-based KORA-S4 study (Kooperative Gesundheitsforschung im Raum Augsburg, Survey 4). Results The FTO risk allele was associated with IR traits and measures of increased body weight. In addition, the TCF7L2 SNP was associated with body weight traits. For the SNPs in the vicinity of INSIG2 and MC4R and for the other examined phenotypes there was no evidence for an association. In PCOS the observed per risk allele effect of FTO intron 1 SNP rs9939609 on BMI was +1.56 kg/m2, whereas it was +0.46 kg/m2 in females of the same age range from the general population as shown previously. Conclusion The stronger effect on body weight of the FTO SNP in PCOS might well have implications for the etiology of the disease.

2010-01-01

43

A brief history of head and neck pathology.  

PubMed

Surgical pathology had its beginnings in the late 1800s. A biopsy that gained much attention was from the larynx of Crown Prince Frederick in 1887. The tissue was seen by Rudolph Virchow and the clinical management of the Prince eventuated in a highly publicized furor. During the first half of the twentieth century, numerous entities in the head and neck were described by dozens of pathologists worldwide. The information was scattered in clinical journals for radiotherapists, general surgeons, and otolaryngologists. The first book on ear, nose, and throat pathology did not appear until 1947 and by 1956 two atlases were available. The book was "Histopathology of the Ear, Nose and Throat" by Eggston and Wolff (1947), and the atlases were the first Armed Forces Institute of Pathology (AFIP) fascicle on salivary gland tumors by Foote and Frazell (1954) and "An Atlas of Otolaryngic Pathology" by Ash and Raum (1956). Clinicopathologic studies accelerated in the 1960s as laryngeal conservation therapy evolved and radiation therapy became more sophisticated. The years 1968 and 1974 mark major events for the emergence of Head and Neck Pathology into a clear-cut discipline. In 1968, Vincent J. Hyams was appointed Director of Otolaryngic Pathology at the AFIP, and 1974 was the publication date of "Tumors of the Head and Neck" by John G. Batsakis. The past 25 years have been filled with hundreds of articles on new entities and the application of fresh technology to old entities. Specialized therapeutic approaches have demanded greater diagnostic precision. This paper touches on a few representative aspects in the history of Head and Neck Pathology during the past 130 years. PMID:11904339

Fechner, Robert E

2002-03-01

44

Das Blüte-Bestäuber-Netz auf Brachflächen : biozönologische Untersuchung zur Bedeutung von Brachen in einer intensiv genutzten Agrarlandschaft  

NASA Astrophysics Data System (ADS)

In der vorliegenden Dissertation wird die Bedeutung von Brachen für Artenvielfalt und Stabilität von Blüte-Bestäuber-Nahrungsnetzen in agrarisch genutzten Landschaften anhand ausgewählter blütenbesuchender Insektengruppen (Syrphidae, Lepidoptera) untersucht. Die Freilandarbeiten fanden von 1998-2000 im Raum der Feldberger Seenlandschaft, Mecklenburg-Vorpommern, statt. Es werden die beiden Hauptnahrungsquellen Nektar und Pollen betrachtet, dabei fanden Untersuchungen zur Intensität der Blüte-Bestäuber-Interaktion auf Stilllegungsflächen, zum flächenbezogenen quantitativen Nektarangebot im Jahresverlauf, zur individuellen Pollennutzung bei Syrphiden und zur Breite und Überlappung der Nahrungsnischen bei den dominanten Arten Episyrphus balteatus, Metasyrphus corollae, Syritta pipiens und Sphaerophoria scripta statt. Im Ergebnis zeigt sich eine hohe Bedeutung der Brachflächen für die Stabilität des Blüte-Bestäuber-Netzes, während die Diversität von anderen, eher landschaftsbezogenen Faktoren abhängig ist. This dissertation examines the importance of fallow land for the diversity and stability of pollination webs in agricultural landscapes as exemplified by selected groups of anthophilous insects (syrphidae and lepidoptera). The field studies were carried out between 1998 and 2000 in the Feldberg lakeland area in the north-east German State of Mecklenburg-Western Pomerania. Observations were made of nectar and pollen as the two main sources of food. Studies were conducted into the intensity of plant-pollinator interaction in set-aside areas, the site-specific quantity of nectar available during the vegetation period and the individual pollen intake of syrphid flies. Different methods were employed to establish the breadth of the trophic niches among the predominant species (Episyrphus balteatus, Metasyrphus corollae, Syritta pipiens and Sphaerophoria scripta) and the extent to which they overlapped. The studies showed that, while fallow land is very important for the stability of plant-pollinator food webs, their diversity depends on other factors that are more closely related to the landscape.

Hahn, Robert

2002-11-01

45

Possibilities for a valorisation of geomorphologic research deliverables  

NASA Astrophysics Data System (ADS)

Many geomorphological studies focus on fundamental research questions in large parts, although there are lots of applied fields like landslide hazard assessment or water framework directive. As fundamental research is a common property, their outcomes should be more "open" and accessible to the public. This means that scientists have to find new ways presenting their results and outcomes besides publishing in scientific journals. This paper shows possibilities for a valorisation of geomorphologic research deliverables using print as well as digital media. Geotrails explain remarkable and exciting landscape features using information boards and become more and more popular and important for tourism in many parts of the world. With the growing interest in environmental change and outdoor activities, print media like field guides reach an increasing number of people. Field guides and Geotrails can be coupled in order to arise awareness about geomorphological landforms and to deliver more specific information on the site beyond the information given on the boards in the field. As field guides are designed for the general public they can be used for educational purposes as well. Today, this information can also be found in the internet offering virtual trips through landscapes using dynamic maps. Here, server side GIS technologies (WebGIS) using standardised interfaces provide new possibilities to show geomorphic data to the public and to share them with the scientific community. Furthermore, data formats like XML or KML are powerful tools for data exchange and can be used in interactive data viewers like Google Earth. We will present the Geotrail "Geomorphologischer Lehrpfad am Fuße der Zugspitze. Das Reintal - Eine Wanderung durch Raum und Zeit" (Bavarian Alps, Germany). Additionally, three geomorphologic WebGIS applications (Geomorphologic map Turtmanntal, Permafrostmap of Austria, Geomorphologic maps of Germany) will exemplify how geomorphologic information and data can be presented in the internet. These examples illustrate the dissemination of geomorphologic research deliverables with modern web technologies and classic print media aimed to laymen, students, and scientists in order to valorise geomorphologic research.

Geilhausen, M.; Götz, J.; Otto, J.-C.; Schrott, L.

2009-04-01

46

PREFACE: NC-AFM 2004: Proceedings of the 7th International Conference on Non-contact Atomic Force Microscopy  

NASA Astrophysics Data System (ADS)

With the ongoing miniaturization of devices and controlled nanostructuring of materials, the importance of atomic-scale information on surfaces and surface properties is growing continuously. The astonishing progress in nanoscience and nanotechnology that took place during the last two decades was in many ways related to recent progress in high-resolution imaging techniques such as scanning tunnelling microscopy and transmission electron microscopy. Since the mid-1990s, non-contact atomic force microscopy (NC-AFM) performed in ultrahigh vacuum has evolved as an alternative technique that achieves atomic resolution, but without the restriction to conducting surfaces of the previously established techniques. Advances of the rapidly developing field of NC-AFM are discussed at annual conferences as part of a series that started in 1998 in Osaka, Japan. This special issue of Nanotechnology is a compilation of original work presented at the 7th International Conference on Non-contact Atomic Force Microscopy that took place in Seattle, USA, 12-15 September 2004. Over the years, the conference grew in size and scope. Atomic resolution imaging of oxides and semiconductors remains an issue. Noticeable new developments have been presented in this regard such as, e.g., the demonstrated ability to manipulate individual atoms. Additionally, the investigation of individual molecules, clusters, and organic materials gains more and more attention. In this context, considerable effort is undertaken to transfer the NC-AFM principle based on frequency modulation to applications in air and liquids with the goal of enabling high-resolution surface studies of biological material in native environments, as well as to reduce the experimental complexity, which so far involves the availability of (costly) vacuum systems. Force spectroscopy methods continue to be improved and are applied to topics such as the imaging of the three-dimensional force field as a function of the distance with atomic resolution, the investigation of near-surface electronic states, the quantification of adhesion forces, and the lateral mapping of surface potentials. The origin of energy dissipation, which is closely related to an in-depth understanding of tip-surface interactions and imaging mechanisms, was the subject of an ongoing discussion and addressed by various theoretical, computational, and experimental contributions. A characteristic of the NC-AFM conference series is the lively and friendly atmosphere, which year after year stimulates scientific discussions between the participants. This time, the programme included 5 invited talks, 84 contributed presentations, and 113 participants; furthermore, three educational lectures were given as part of a pre-conference workshop targeted at NC-AFM newcomers, which was attended by 30 participants. I would like to thank the members of the international steering committee and the programme committee for their continued effort in organizing the meeting. Special thanks go to the chair of the programme and local organizing committees S Fain and the conference manager J Kvamme for making the meeting a success. Financial support is acknowledged from the corporate sponsors MikroMasch USA, Nanonis GmbH, Nanosurf AG, Omicron Nanotechnology, PSIA, Inc., and RHK Technology, as well as from the institutional sponsors National Science Foundation and PNNL/UW Joint Institute for Nanoscience. Finally, I would like to express my gratitude to everyone who participated in assembling this special issue including the authors, the reviewers, and, in particular, the excellent and experienced journal team from the Institute of Physics Publishing headed by Nina Couzin, for devoting their time and efforts so that we could make this issue a useful representation of the progress in NC-AFM while maintaining our tight publication schedule. In conclusion, I would like to mention that the Seattle conference was the first one of the NC-AFM series that took place in the USA. As such, it was part of a series of recent activities within the USA, which will

Schwarz, Udo

2005-03-01

47

MT3250BA: a 320×256-50µm snapshot microbolometer ROIC for high-resistance detector arrays  

NASA Astrophysics Data System (ADS)

This paper reports the development of a new microbolometer readout integrated circuit (MT3250BA) designed for high-resistance detector arrays. MT3250BA is the first microbolometer readout integrated circuit (ROIC) product from Mikro-Tasarim Ltd., which is a fabless IC design house specialized in the development of monolithic CMOS imaging sensors and ROICs for hybrid photonic imaging sensors and microbolometers. MT3250BA has a format of 320 × 256 and a pixel pitch of 50 µm, developed with a system-on-chip architecture in mind, where all the timing and biasing for this ROIC are generated on-chip without requiring any external inputs. MT3250BA is a highly configurable ROIC, where many of its features can be programmed through a 3-wire serial interface allowing on-the-fly configuration of many ROIC features. MT3250BA has 2 analog video outputs and 1 analog reference output for pseudo-differential operation, and the ROIC can be programmed to operate in the 1 or 2-output modes. A unique feature of MT3250BA is that it performs snapshot readout operation; therefore, the image quality will only be limited by the thermal time constant of the detector pixels, but not by the scanning speed of the ROIC, as commonly found in the conventional microbolometer ROICs performing line-by-line (rolling-line) readout operation. The signal integration is performed at the pixel level in parallel for the whole array, and signal integration time can be programmed from 0.1 µs up to 100 ms in steps of 0.1 µs. The ROIC is designed to work with high-resistance detector arrays with pixel resistance values higher than 250 k?. The detector bias voltage can be programmed on-chip over a 2 V range with a resolution of 1 mV. The ROIC has a measured input referred noise of 260 µV rms at 300 K. The ROIC can be used to build a microbolometer infrared sensor with an NETD value below 100 mK using a microbolometer detector array fabrication technology with a high detector resistance value (? 250 K?), a high TCR value (? 2.5 % / K), and a sufficiently low pixel thermal conductance (Gth ? 20 nW / K). The ROIC uses a single 3.3 V supply voltage and dissipates less than 75 mW in the 1-output mode at 60 fps. MT3250BA is fabricated using a mixed-signal CMOS process on 200 mm CMOS wafers, and tested wafers are available with test data and wafer map. A USB based compact test electronics and software are available for quick evaluation of this new microbolometer ROIC.

Eminoglu, Selim; Akin, Tayfun

2013-06-01