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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
08:39 IWF (Göttingen) English 1979

Protoplasmic Streaming

Agitation, circulation, rotational streaming and their variants (multi-striate, sleeve-type, and fountain streaming) as well as shuttle streaming are shown in the following: Allium, Tradescantia, Elodea, Vallisneria, Nitella, Acetabularia, Closterium, Phycomyces, Limnobium and Physarum.
  • Published: 1979
  • Publisher: IWF (Göttingen)
  • Language: English
10:39 IWF (Göttingen) English 1983

Locomotion of Plant Cells

Flagellar movement is visualized using spirochaetes, the algal flagellates Chlamydomonas, Volvox, Euglena, Peranema, Gymnodinium, and the gametes of Chara and Hydrodictyon. Amoeboid movement is demonstrated with Physarum and Amoeba proteus, sliding on Beggiatoa, Oscillatoria, Spirulina and on selected diatoms and desmids.
  • Published: 1983
  • 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
00:43 IWF (Göttingen) German 2005

Plasmaströmung in Algen und Wurzelhaarspitzen

Rotationsströmung in Zellen der Armleuchteralge Nitella flexilis. Plasmaströmung in der Wurzelhaarspitze von Limnobium stoloniferum. Aus der CD-ROM: BEREITER-HAHN, JÜRGEN (Frankfurt a. M.). Die Zelle I - Leben aus Licht und Luft. (C 7100)
  • Published: 2005
  • Publisher: IWF (Göttingen)
  • Language: German
00:57 IWF (Göttingen) German 2005

Endosymbiontentheorie

Amoeba proteus, kombiniert mit 3D-Darstellung von Chloroplast und Mitochondrium. Pantoffeltierchen (Paramecium bursaria) mit einzelligen Algen der Gattung Chlorella im Zytoplasma. Aus der CD-ROM: BEREITER-HAHN, JÜRGEN (Frankfurt a. M.). Die Zelle I - Leben aus Licht und Luft. (C 7100)
  • Published: 2005
  • 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
07:54 IWF (Göttingen) English 1976

Electron Microscopic Preparation Techniques - 5. Spreading Technique for Preparing Isolated DNA

DNA and cytochrome c spread on the surface of a salt solution. The spreading area is dabbed at random with filmed grids. In this way a thin layer of protein and DNA adheres to the grid. Contrast enhancement by rotation cone shadowing with platinum-iridium alloy.
  • Published: 1976
  • Publisher: IWF (Göttingen)
  • Language: English
20:39 IWF (Göttingen) English 1976

Electron Microscopic Preparation Techniques - 6. Freeze Etching

Preparation of the specimen by glycerol treatment and centrifugation; freezing the specimen; preparing the freeze-etching plant; course of fracturing, etching and shadowing the replica with platinum-iridium alloy and carbon and cone shadowing with carbon; reallife film and animation sequences; cleaning the replicas and mounting on carrier grids. Result: freeze-etched replica of a longitudinally fractured cell of the green alga Ankistrodesmus braunii.
  • Published: 1976
  • Publisher: IWF (Göttingen)
  • Language: English
09:00 IWF (Göttingen) English 1976

Electron Microscopic Preparation Techniques - 1. Making a Plastic Carrier Film

Making a carbon-reinforced carrier film by the "flow out" method, floating off the film on the water surface, judging its quality, coating support grids with film, removing the coated grids from the water surface. Reinforcing the films by coating with evaporated carbon. Demonstration of the results.
  • Published: 1976
  • Publisher: IWF (Göttingen)
  • Language: English
20:39 IWF (Göttingen) German 1976

Elektronenmikroskopische Präparationsmethoden - 6. Gefrierätzung

Vorbereitung des Objekts durch Glyzerinbehandlung und Zentrifugierung; Einfrieren der Präparate; Vorbereitung der Gefrierätzanlage; Ablauf von Gefrierbruch, Ätzung und Herstellung des Abdrucks durch Metall-Kohle-Schrägbedampfung und Kegelbedampfung mit Kohle; natürlicher Ablauf und schematische Darstellung; Reinigung und Aufnehmen der Abdrücke auf Objektträgernetze. Resultat: Gefrierätzabdruck eines Längsbruches durch eine Zelle der Grünalge Ankistrodesmus braunii.
  • Published: 1976
  • Publisher: IWF (Göttingen)
  • Language: German
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
16:50 IWF (Göttingen) Silent film 1963

Oberharzer Erzbergbau um 1920 - 1. Der Bergbau

The film covers the first part of an three-part film on the Upper harz ore mining industry, shot in 1923. It begins with shots of the hydroeconomic drain an dpond system, and of the shaft system "Silbersegen", conveyance of which was done with one water wheel up to 1931 and of the modern installed shaft "Kaiser-Wilhelm-II". Then follows the "conveyance" of the miners in the Kaiser-Wilhelm shaft, with a brief view of the hydraulic head machine in this shaft and of the power generating plant in the Ernst-August gallery. Winning and conveyance underground are then shown in detail: long-distance conveyance in closed trains with electric trolley locomotives, winning of the crude or by drilling and blasting and removal to the tubs, which are brought to the surface in the cage.
  • Published: 1963
  • Publisher: IWF (Göttingen)
  • Language: Silent film
13:47 IWF (Göttingen) Silent film 1963

Oberharzer Erzbergbau um 1920 - 3. Die Verhüttung

The film covers the third part of an, originally, three-part film on the Upper Harz ore mining industry, shot in 1923. Here we see the smelting in the Frankenscharrn smelting plant in Clausthal, which was first operated in 1554; first step is the roasting and desulphurization of the ore concentrates in a one-story rotary furnace with subsequent dead-roasting and sintering in a converter. The roasting charge is then smelted in blast-furnaces with lateral gas exhaust. We are also shown the slag tapping and, finally, the lead tapping. In addition to the silver-bearing lead, which is cast in bars, copper-bearing compounds are also won.
  • Published: 1963
  • Publisher: IWF (Göttingen)
  • Language: Silent film
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
11:14 IWF (Göttingen) German 1981

Mechanismus des Luftwechsels bei Labyrinthfischen

How labyrinthine fish breathe air using 3 examples; Ctenopoma kingsleyae, Osphronemus gouramy and Anabas testudineus. Dissection and demonstration of breathing in real-time and slow-motion film. Description of the breathing mechanisms using X-ray cinematography and animations.
  • Published: 1981
  • Publisher: IWF (Göttingen)
  • Language: German
07:38 IWF (Göttingen) Silent film 1965

Tilapia heudeloti (Cichlidae) - Balz

Senegal cichlid. Female performing the courtship display: impressing, tail beating, "bowing" before the congener. The male stays with the female digging the spawning ground. Both partners in preparation of spawning.
  • Published: 1965
  • Publisher: IWF (Göttingen)
  • Language: Silent film
19:32 IWF (Göttingen) German 1999

Polarität bei Pflanzen

Polarity is a basic phenomenon in plants. Induction of polarity by blue light is demonstrated on cellular level in side branch formation of the alga Vaucheria (Siphonales) and in the germination of the spermatized eggs of the brown alga Pelvetia. Polarity, once established in a cell persists during the whole lifetime of a plant. Expression of polarity is illustrated in roots and in under water leaves of higher plants; in the case of the leave it is characterized by the flux of protons from under to upper side. The influence of proton flow in leave and root is molecularly visualised using computer animations.
  • Published: 1999
  • Publisher: IWF (Göttingen)
  • Language: German
10:59 IWF (Göttingen) English 1984

Production of Purified Clostridia Toxoid Vaccines by Cascade Ultrafiltration

A system is described which consists firstly of identifying pathogen anaerobes in tropical grazing lands by means of GLC and biometrical comparison of metabolically produced fatty acid patterns with such of known reference strains. Locality specific anaerobes may then be continuously cultivated in an especially designed bioreactor and their toxins separated through ultra-filtration. The filtration process is a continuous two step procedure. At first the microbes are separated from the spent broth with a hollow fiber of approx. 1 Mio. NMCO and in the second stage the toxin is concentrated and freed of allergenic peptides with a hollow fiber filter of 20.000 NMCO. The highly concentrated formalinized toxoid may be applicated intradermically beside the tail of the animal in a volume of 0,25 ml with a dermo-jet.
  • Published: 1984
  • Publisher: IWF (Göttingen)
  • Language: English
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
01:25 IWF (Göttingen) German 2006

Gefrierbruch-Technik

Elektronenmikroskopisches Bild einer Gap junction im Gefrierbruch. Animation zum Aufbau einer Gap junction und zur Technik des Gefrierbruchs am Beispiel von Gap junctions. Aus der CD-ROM: BEREITER-HAHN, JÜRGEN; WINFRIED S. PETERS (Frankfurt a. M.). Die Zelle III - Innere Grenzen - Membranen und Transport. (C 7102)
  • Published: 2006
  • Publisher: IWF (Göttingen)
  • Language: German
08:12 IWF (Göttingen) German 1978

Einstufige Schubzentrifuge - Trennung von Feststoff und Flüssigkeit unter verschiedenen Betriebsbedingungen

Beim Zentrifugieren einer Suspension werden Kuchenbildung und Transport unter Variation der Trommellänge, Drehzahl, Schubfrequenz und Vorschublänge mit stroboskopischen Filmaufnahmen gezeigt.
  • Published: 1978
  • Publisher: IWF (Göttingen)
  • Language: German
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