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06:01 IWF (Göttingen) English 1976

Oscillations of Molecules in Melamine Crystal Lattices with Hydrogen Bonds

Translatory and torsional vibrations of the molecules. Using melamine for an example, the elastic properties of the intermolecular hydrogen bonds are demonstrated. Using the thermally induced vibrations at 60 and 300 K it is shown, that they are the mechanical storage means of the specific heat of the melamine crystal.
  • Published: 1976
  • Publisher: IWF (Göttingen)
  • Language: English
21:26 IWF (Göttingen) English 1984

Chromatography - 1. Separation Procedures, Theory and Applications

Adsorption, distribution, ion exchange and gelatin permeation are the basic procedures which lead to a chromatographical fractionation of mixtures of substances, for examples, of dye pigment in a chromatographic system consisting of a mobile and a stationary phase. The kinetic theory, the theory of separation in stages and the van-Deemter equation provide the theoretical basis for this physical-chemical method of separation. The techniques of thin-layer chromatography, fluid-column chromatography and gas chromatography make it possible to combine separations with quantitative analyses in the form of various analysis systems.
  • Published: 1984
  • Publisher: IWF (Göttingen)
  • Language: English
13:16 IWF (Göttingen) English 1985

Activator-Inhibitor - A Model of Biological Pattern Formation

In the development of higher organisms, pattern forming reactions must be involved. In the movie, a yet hypothetical two-component reaction is analysed which is able to generate patterns. Computer simulations made on the basis of two coupled non-linear differential equations show the time course and the regulatory properties of this reaction.
  • Published: 1985
  • Publisher: IWF (Göttingen)
  • Language: English
13:17 IWF (Göttingen) German 1985

Aktivator-Inhibitor - Ein Modell zur biologischen Musterbildung

Das mathematische Modell wird in Computersimulationen interpretiert, wobei sich die verschiedenen Muster durch Variation der Parameter bilden: Anstoßen durch statistische Schwankungen, verschiedene Regenerationsabläufe, spezifische und unspezifische Induktionen, oszillierende Muster und Ausrichtungen, periodische Muster sowie regelmäßige Muster während des Wachstums.
  • Published: 1985
  • Publisher: IWF (Göttingen)
  • Language: German
10:02 IWF (Göttingen) English 1967

Differentiation and Growth in Micrasterias denticulata (Conjugatae)

Desmids in nutrient solution. Nuclear division and septum formation, development of the new half-cells, migration of the nuclei and chloroplasts into the half-cells, differentiation of the chloroplasts and cell walls. Osmotic experiments to demonstrate the mechanics of morphogenesis: plasmolysis by glucose solution, cell wall formation under conditions of reduced turgor. With time-lapse.
  • Published: 1967
  • Publisher: IWF (Göttingen)
  • Language: English
11:02 IWF (Göttingen) English 1980

Stage Specific Protoplasm Streaming in the Stalk of Acetabularia mediterranea

The formation of intracellular transport systems in the course of cell differentiation. A network of cytoplasmic filaments transports chloroplasts, a system of wider cytoplasmic bands moves cell inclusions and generative nuclei. The cytoplasmic bands follow along the filaments and are faster than the movement of the chloroplasts. With time-lapse.
  • Published: 1980
  • Publisher: IWF (Göttingen)
  • Language: English
11:05 IWF (Göttingen) English 1980

Effect of Cytochalasin B and Anti-Microtubule Inhibitors on Protoplasmic Streaming in Acetabularia mediterranea

All intracellular movements are reversibly inhibitedby the anti-microfilament agent cytochalasin B. The microtubule inhibitors colchicine, chlorisopropyl-N-phenyl-carbamate (CIPC), amiprophosmethyl (APM) reversibly inhibit nuclear migration and have no influence on chloroplast movement. With time-lapse.
  • Published: 1980
  • Publisher: IWF (Göttingen)
  • Language: English
10:03 IWF (Göttingen) German 1967

Differenzierung und Wachstum von Micrasterias denticulata (Conjugatae)

Zieralgen in Nährlösung. Kernteilung und Septumbildung, Entwicklung der neuen Halbzelle, Einwandern des Zellkerns und der Chloroplasten, Chloroplastendifferenzierung und Zellwandbildung. Osmotische Versuche zur Mechanik der Formbildung: Plasmolyseform in Glukoselösung, Zellwandbildung bei reduziertem Turgor. Mit Zeitraffung.
  • Published: 1967
  • Publisher: IWF (Göttingen)
  • Language: German
11:13 IWF (Göttingen) English 1970

Sexual Reproduction in the Green Alga Hydrodictyon reticulatum

The water-net. Splitting of the protoplasts into many uninucleate portions, formation of flagella, mobilization and emergence of gametes, copulation (fusion at posterior or flagellar poles), withdrawal of flagella, rounding-off of zygote, development and release of meiospores, polyhedral stage, formation and growth of disc-net.
  • Published: 1970
  • Publisher: IWF (Göttingen)
  • Language: English
11:37 IWF (Göttingen) English 1978

Life History of Ectocarpus siliculosus (Phaeophyta)

Vegetative reproduction and alternation of generations in the brown alga under laboratory conditions: formation of plurilocular sporangia, liberation and germination of mitospores, growth to sporophyte generation; formation of unilocular sporangia, liberation and germination of meiospores, formation of plurilocular gametangia, release and copulation of gametes. Microcinematography, partly in time-lapse, animated graphics of life cycle.
  • Published: 1978
  • Publisher: IWF (Göttingen)
  • Language: English
41:41 IWF (Göttingen) German 1988

Heutige und eiszeitliche Vergletscherung Hochasiens - Ergebnisse der Südtibet- und Mt. Everest-Expedition 1984

Neue Befunde zur aktuellen Glaziologie, Geomorphologie und Klimatologie Hochasiens sowie zur vorzeitlichen Gletscherbedeckung und Eiszeitforschung anhand südtibetischer Beispiele: Heutige Vergletscherung, Prozesse der Reliefentwicklung nach glazialer Verformung, Vergletscherungsgeschichte und Rekonstruktion eines hocheiszeitlichen subtropischen Inlandeises (Tibet-Eis als eigentlicher Auslöser der Hocheiszeit?).
  • Published: 1988
  • Publisher: IWF (Göttingen)
  • Language: German
08:30 IWF (Göttingen) German 1976

Entwicklung von Sphaeroplea annulina (Chlorophyta)

Under conditions of limiting oxygen vegetative reproduction stops and is replaced by sexual reproduction. Metamorphosis of multinucleate cells by antheridia and oogonia. Production of spermatozoids and eggs. Chemotatic attraction of the male gametes, their penetration into the oogonia, fertilization, development of spherical hypnozygotes, zygote germination, growth of the initially bicillate zoospores to threads.
  • Published: 1976
  • Publisher: IWF (Göttingen)
  • Language: German
06:55 IWF (Göttingen) English 1970

Asexual Reproduction in the Green Alga Hydrodictyon reticulatum

The water-net. Formation of tubular network: darkening of the cell, disappearance of the pyrenoids, "pavement stage", differentiation and motility of zoospores, assembly to mesh structure and immobilization of the zoospores, dissolution of old cell-wall, growth of daughter colony up to fully grown net. Flagellar movements and incompletely divided double zoospores.
  • Published: 1970
  • Publisher: IWF (Göttingen)
  • Language: English
11:16 IWF (Göttingen) German 1970

Geschlechtliche Fortpflanzung der Grünalge Hydrodictyon reticulatum

Wassernetz. Aufteilung des Protoplasten in viele einkernige Portionen, Ausbildung der Geißeln, Beweglichwerden und Austreten der Gameten, Kopulation (Fusion am Hinterende oder am Geißelpol), Einschmelzen der Geißeln und Abrundung der Zygote, Differenzierung und Schlüpfen der Meiosporen, Polyederstadium, Bildung und Wachstum des Scheibennetzes.
  • Published: 1970
  • Publisher: IWF (Göttingen)
  • Language: German
08:30 IWF (Göttingen) English 1983

Ecology of Larger Foraminifera

Nummulites gizehensis is one of numerous larger foraminifera which from the Carboniferous to the Tertiary contributed to the formation of sedimentary rocks. In the Allgäu, Bavaria, nummulitic limestones are exposed. Recent larger foraminifera occur, like their fossil allies, in warm shallow seas. Upon their death, their shells turn into marine sand. This is illustrated by a Hawaiian sandy beach. The sublittoral algal benthos of a Hawaiian rockpool is a habitat of these sand producers. Here Sorites variabilis, Amphistegina lobifera, Amphistegina lessonii, Peneroplis pertusus and Heterostegina depressa occur the ecology of which is treated in the film. In the interstice of the algae they are protected against surf and solar radiation.
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: English
10:39 IWF (Göttingen) English 1982

The Larger Foraminifer Heterostegina depressa - Organization and Growth of the Megalospheric Generation

The foraminiferan constructs a test and attaches it to the substrate with elastic threads. There are large numbers of symbionts (Diatoms) in its protoplasm; Heterostegina gets its nourishment from them. The film shows test anatomy and organic protective sheaths, cytoplasmic streaming and symbiont transport, local movement with pseudopodia and chamber formation in detail. With time-lapse.
  • Published: 1982
  • Publisher: IWF (Göttingen)
  • Language: English
10:12 IWF (Göttingen) English 1983

The Larger Foraminifer Heterostegina depressa - Multiple Fission in Microspheric and Megalospheric Generation

The protoplasm retreats into the shell shortly before multiple fission. It then flows out through a system of channels before reforming on the shell surface. The second chamber is formed shortly after subdivision into daughter individuals. After a 13 h resting phase the offspring, which are still connected by maternal protoplasmic strands, are dispersed. They settle in the immediate vicinity and start to grow new shells. Time-lapse.
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: English
08:38 IWF (Göttingen) English 1989

Calcarinidae - Larger Foraminiferes of the South Sea

The calcarinidae, which measure only a millimetre in size and have shells composed of calcium carbonate, mainly occur in the Western Pacific. They are characterized by radiating appendices of the shell, which give them a starlike appearance. The following calcarinidae are presented: Baculogypsina sphaerulata, Calcarina calcar, Calcarina defrancii, Calcarina gaudichaudii, Calcarina hispida. The presentation includes quick-motion sequences.
  • Published: 1989
  • Publisher: IWF (Göttingen)
  • Language: English
14:05 IWF (Göttingen) Silent film 2007

Mausohrfledermaus

The DVD contains the IWF-films: E 1837 "Glossophaga soricina (Phyllostomatidae) - Ingestion of Food (Licking)"; E 1838 "Glossophaga soricina (Phyllostomatidae) - Flight in Place"; C 1094 "Biology of the Mouse-eared Bat (Myotis myotis)"; E 1631 "Myotis myotis (Vespertilionidae) - Birth"; C 884 "Sensory Abilities of the Bat Myotis myotis Taking up Food from the Ground".
  • Published: 2007
  • Publisher: IWF (Göttingen)
  • Language: Silent film
09:46 IWF (Göttingen) German 1987

Interzelluläre Kommunikation über Gap junctions

Gap junctions dienen der Informationsübertragung in Geweben und Organen tierischer Herkunft. Sie bestehen aus Ansammlungen feiner Kanälchen, die einen direkten Kontakt zwischen benachbarten Zellen herstellen und so eine schnelle Nachrichtenübermittlung zulassen. Darstellung des Aufbaus einer gap junction in Trick- und EM-Aufnahmen. Demonstration der Kopplung von Zellen durch Ausbreitung von Fluoreszensfarbstoff (Lucifer yellow) und Übertragung elektrischer Signale.
  • Published: 1987
  • Publisher: IWF (Göttingen)
  • Language: German
13:34 IWF (Göttingen) German 1979

Zweistufige Schubzentrifuge - Trennung von Feststoff und Flüssigkeit unter verschiedenen Betriebsbedingungen

During the mechanical separation of a liquid in a two-stage pusher centrifuge the starting process, the formation and the transport of a solid cake will be shown with the variations of the mass flow of the suspension, the number of revolutions, the frequency of the pusher plate and the length of the conveyance. By means of a synchronization device and a stroboscopical lighting the rotating barrels of the centrifuge apparently come to a standstill.
  • Published: 1979
  • Publisher: IWF (Göttingen)
  • Language: German
26:16 IWF (Göttingen) English 1995

Laser Microbeam and Optical Tweezers - Physical Principles. Applications in Cell Biology and Biotechnology

With the aid of laser beams (UV and IR) which can be coupled with the light path of an optical microscope, objects such as cells can be more gently manipulated without mechanical contact. The UV laser (laser microbeam) serves to cut and drill, the IR laser (optical tweezers) to hold and move particles. The film explains the method and shows practical examples. (Micro, real-life and animation sequences).
  • Published: 1995
  • Publisher: IWF (Göttingen)
  • Language: English
11:39 IWF (Göttingen) German 1978

Entwicklung von Ectocarpus siliculosus (Phaeophyta)

Vegetative Vermehrung und Generationswechsel der Braunalge unter Laborbedingungen: Bildung plurilokulärer Sporangien, Freisetzung und Keimung von Mitosporen, aufwachsende Sporophyten; Bildung unilokulärer Sporangien, Freisetzung und Keimung von Meiosporen, Bildung plurilokulärer Gametangien, Freisetzung und Kopulation von Gameten. Mikrokinematographische Aufnahmen, z. T. Zeitraffung, Schemata des Entwicklungsgangs.
  • Published: 1978
  • Publisher: IWF (Göttingen)
  • Language: German
08:44 IWF (Göttingen) English 1982

Hormone Effects in Sexual Reproduction of Brown Algae

Attached female Ectocarpus gametes attract the male gametes with the pheromone ectocarpen, which they release into the sea water. Mature Laminaria egg cells effect the release of their pheromone. With high-speed, time-lapse and animated sequences.
  • Published: 1982
  • Publisher: IWF (Göttingen)
  • Language: English
13:40 IWF (Göttingen) English 1991

Fertilization Biology in Fucus (Phaeophyceae) - Dioecism and Moecism

While the dioecious brown alga Fucus serratus releases its sexual products in two phases - gametangia at outgoing tide and gametes at incoming tide - the monoecious species Fucus spiralis releases gametangia and gametes with the incoming tide. The monoecious species releases fertilized egg cells; in the dioecious species, the gametes must find each other on the sea floor. Biotope photography, partially with time-lapse.
  • Published: 1991
  • Publisher: IWF (Göttingen)
  • Language: English
13:42 IWF (Göttingen) German 1991

Befruchtungsbiologie bei Fucus (Phaeophyceae) - Diözie und Monözie

Während die diözische Braunalge Fucus serratus ihre Geschlechtsprodukte in zwei Phasen abgibt - Gametangien bei Niedrigwasser, Gameten bei auflaufendem Wasser - , entläßt die monözische Art Fucus spiralis Gametangien und Gameten bei auflaufendem Wasser. Die monözische Art entläßt befruchtete Eizellen, die diözische Art ist auf eine Gametenfindung am Meeresboden angewiesen. Biotopaufnahmen; z. T. in Zeitraffung.
  • Published: 1991
  • Publisher: IWF (Göttingen)
  • Language: German
08:18 IWF (Göttingen) German 1989

Calcarinidae - Großforaminiferen der Südsee

Die millimetergroßen, kalkschaligen Calcariniden leben vor allem im Westpazifik. Charakteristisch sind radiär ausstrahlende Schalenfortsätze, die ihnen ein sternförmiges Aussehen geben. Vorgestellt werden Baculogypsina sphaerulata, Calcarina calcar, Calcarina defrancii, Calcarina gaudichaudii, Calcarina hispida. Mit Zeitraffung.
  • Published: 1989
  • Publisher: IWF (Göttingen)
  • Language: German
17:58 IWF (Göttingen) German 1997

Jagdkäfer und Kupferstecher - Aspekte einer Räuber-Beute-Beziehung

Der Kupferstecher Pityogenes chalcographus hat eine große ökonomische Bedeutung, da er riesige Schäden in Fichtenforsten verursacht. Seine Häufigkeit wird mit Lockstoff-Fallen biotechnisch überwacht, in denen auch sein natürlicher Gegenspieler, der Jagdkäfer Nemosoma elongatum, regelmäßig als Beifang auftritt. Larven und Imagines leben unter der Rinde in den Brutsystemen des Kupferstechers, wo der Jagdkäfer ihn zu überwältigen vermag. Die Imago ernährt sich von erwachsenen Borkenkäfern, während die 3-4 Larvenstadien Borkenkäferlarven und -puppen fressen. Der Film stellt die Biologie beider Arten vor und beleuchtet einige ökologische Grundlagen ihrer Räuber-Beute-Beziehung. Mit Zeitraffung, unter Verwendung von Aufnahmen aus Film C 1450.
  • Published: 1997
  • Publisher: IWF (Göttingen)
  • Language: German
06:58 IWF (Göttingen) German 1970

Ungeschlechtliche Fortpflanzung der Grünalge Hydrodictyon reticulatum

Wassernetz. Schlauchnetzbildung: Dunkelwerden der Zelle, Verschwinden der Pyrenoide, "Pflasterstadium", Differenzierung und Bewegung der Zoosporen, Ordnen zum Netz und Ruhigwerden der Zoosporen, Platzen der Wand, Ausbildung des Tochternetzes, Schlauchnetzwachstum. Geißelbewegung und Doppelstadien an isolierten Zoosporen.
  • Published: 1970
  • Publisher: IWF (Göttingen)
  • Language: German
08:32 IWF (Göttingen) German 1983

Ökologie der Großforaminiferen

Großforaminiferen bewohnten im Alttertiär die Tethys. Ihre Gehäuse bilden heute als Nummulitenkalke mächtige Gesteinsschichten, z. B. am Rande der Kalkalpen. Die heute lebenden Verwandten besiedeln entsprechende Lebensräume, durchlichtete Flachmeere der Tropen und Subtropen. Die Sande am Strand von Hawaii bestehen hauptsächlich aus Gehäusen rezenter Foraminiferen. Die die Felsküsten dicht besiedelnden Braun- und Rotalgen sind Substrat für Sorites, Amphistegina, Peneroplis und Heterostegina.
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: German
10:14 IWF (Göttingen) German 1983

Die Großforaminifere Heterostegina depressa - Vielteilung der mikrosphärischen und der megalosphärischen Generation

Kurz vor der Vielteilung zieht sich das Protoplasma in den inneren Gehäuseteil zurück. Darauf fließt es durch das Kanalsystem heraus und formiert sich auf der Schale neu. Nach der Aufteilung in Tochterindividuen wird bald die zweite Kammer angelegt. Nach einer etwa 13stündigen Ruhezeit werden die zweikammerigen Jungen durch restliche mütterliche Protoplasmafäden vom Gehäuse wegtransportiert. Die Jungen siedeln sich in der Nähe an und wachsen unter Kammerbildung heran. Zeitraffung.
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: German
10:41 IWF (Göttingen) German 1982

Die Großforaminifere Heterostegina depressa - Organisation und Wachstum der megalosphärischen Generation

Die Foraminifere bildet eine Hülle und befestigt diese mit Hilfe elastischer Fäden am Substrat. Im Protoplasma sind zahlreiche Symbionten (Kieselalge) enthalten, von denen Heterostegina lebt. Der Aufbau des Gehäuses und der Hülle, Schalenstruktur, Protoplasmaströmung und Symbiontentransport, Ortsbewegung mittels Pseudopodien und Kammerbau werden im Detail dargestellt. Mit Zeitraffung.
  • Published: 1982
  • Publisher: IWF (Göttingen)
  • Language: German
02:04 IWF (Göttingen) German 1985

Photophobische Reaktionen - Navicula

Pennales. Autonomous reversal rhythm in Navicula peregrina and step-down-reaction in darkness or step-up-reaction in bright light. Slight time-lapse and animation.
  • Published: 1985
  • Publisher: IWF (Göttingen)
  • Language: German
11:14 IWF (Göttingen) German 1972

Biologie der Mausohrfledermaus Myotis myotis

The film shows the most important biological characteristics of Myotis myotis in the course of one year which, at the same time, reflect those its life. A cave in the "Fraenkische Schweiz" is shown as its winter quarters, the summer quarters (i. e. the lying-in-room) being on the loft of St. Martin's Church at Bamberg. Interesting ways of acting are rendered by the proceedings of birth; it is the active assistance of a young one during parturition, the tightening of the navelstring and the act of detaching it that is unparalleled among mammals. Food intake from the soil, way of eating, swimming as well as the surprising flushing from water show some ways of living of Myotis myotis. The cycle of the year is concluded by the return into winter quarters.
  • Published: 1972
  • Publisher: IWF (Göttingen)
  • Language: German
07:09 IWF (Göttingen) Silent film 1975

Glossophaga soricina (Phyllostomatidae) - Flug auf der Stelle

The film shows slow motion takes of the hovering flight of a glossophagine bat whirring on the spot while licking honey water from a pipette. The kinematics of the hovering flight can be observed in takes from the side, from above and from the front. The downward beat of the wings takes place with out-stretched, spread wings with a considerable inclination to the airflow. During the upward sweep a functional division of the wings takes place: the arm part is gathered and led up with little air resistance, the hand is turned sharply so that its morphological upper side receives a positive inclination angle relative to the oncoming airflow. In this way lift may be produced in the upward as well as the downward movements.
  • Published: 1975
  • Publisher: IWF (Göttingen)
  • Language: Silent film
01:05 IWF (Göttingen) Silent film 1976

Flug auf der Stelle - Blütenbesuchende Fledermaus (Glossophaga soricina)

Hovering in place, seen from the side, from above and from the front. With slow motion.
  • Published: 1976
  • Publisher: IWF (Göttingen)
  • Language: Silent film
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