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Showing papers by "University of Kiel published in 1971"



Journal ArticleDOI
TL;DR: The distribution of planktonic Foraminifera in South Pacific sediments reflects the environments of production in surface waters and those of preservation on the ocean floor as mentioned in this paper, and the interrelation of clusters is examined by temperature-solution rank analysis.

253 citations


Journal ArticleDOI
TL;DR: In this article, a residence time of about one week for living Foraminifera larger than 150 μ is proposed for fertile regions, implying life spans of no more than about 2 weeks.

245 citations


Journal ArticleDOI
TL;DR: The hitherto unknown compounds Ca2CuO3 and SrCuO2 were prepared and the structure determined by investigations of single crystal X-ray data as discussed by the authors, and the results see „Inhaltsubersicht”
Abstract: Ca2CuO3 und SrCuO2 wurden erstmals dargestellt und an Einkristalldaten die Kristallstruktur bestimmt. Ca2CuO3 ist isotyp mit Sr2CuO3; Raumgruppe D-Immm; a = 12,239, b = 3,779, c = 3,259 A. SrCuO2 ist isotyp mit einer Ni-haltigen Verbindung der Zusammensetzung SrCu0,75Ni0,25O2; Raumgruppe D—Cmcm; a = 3,565; b = 16,326; c = 3,921 A. The hitherto unknown compounds Ca2CuO3 and SrCuO2 were prepared and the structure determined by investigations of single crystal X-ray data. Results see „Inhaltsubersicht”.

217 citations


Journal ArticleDOI
TL;DR: The Conradi-Hünermann type of C.p. with predominantly epiphyseal, frequently asymmetric calcifications and dysplastic skeletal changes was reported in combination with cataracts in 17% and with skin changes in 28% of cases, which seems to be a lethal condition leading to death usually before the end of the first year of life.
Abstract: Based on the experience of the Kiel registry of bone dysplasias and on an extensive review of the literature, the clinical and genealogic data of two major types of Chondrodysplasia punctata are presented and discussed. The Conradi-Hunermann type of C.p. with predominantly epiphyseal, frequently asymmetric calcifications and dysplastic skeletal changes was reported in combination with cataracts in 17% and with skin changes in 28% of cases. It has a relatively good prognosis and is possibly caused by a dominant mutation. Genetic heterogeneity and the influence of environmental factors cannot be excluded in this type. The rhizomelic type of C.p. with severe, symmetrical proximal shortening of the extremities, and marked metaphyseal changes was reported to be combined with cataracts in 72% of the cases and with skin changes in 28%. It seems to be a lethal condition leading to death usually before the end of the first year of life. It is probably caused by the homozygous state of an autosomal gene. Other types of Chondrodysplasia punctata possibly exist. Chondrodysplasia punctata has been confused particularly with Zellweger's cerebrohepato-renal syndrome and with multicentric epiphyseal ossification in multiple epiphyseal dysplasia.

202 citations


Journal ArticleDOI
01 Oct 1971-Science
TL;DR: Membrane-enclosed fecal pellets of planktonic herbivores were sampled at several depths in the Baltic Sea and off Portugal by means of a Simonsen multinet and found that siliceous skeletons were protected from dissolution during settling by a membrane around the pellet.
Abstract: Membrane-enclosed fecal pellets of planktonic herbivores were sampled at several depths in the Baltic Sea (459 meters deep) and off Portugal (4000 meters deep) by means of a Simonsen multinet. Pellets contained mainly empty shells of planktonic diatoms and silicoflagellates. Two kinds of fecal pellets were found, those with the remains of one species (for example, Thalassiosira baltica) and those with the remains of several species (for example, Chaetoceros, Achnanthes, and Thalassiosira). Siliceous skeletons were protected from dissolution during settling by a membrane around the pellet.

172 citations


Journal ArticleDOI
TL;DR: The absolute vertical muon intensity in the range 0.2 -1000 GeV/c has been determined from four different measurements as mentioned in this paper, which is 10 - 25% higher than previous spectra which have usually been normalized to the intensity at 1 GeV /c given by Rossi in 1948.

171 citations


Journal ArticleDOI

78 citations


Journal ArticleDOI
TL;DR: The experimental results could be described by extending the Hodgkin-Huxley equations introducing two terms of potassium inactivation and the steady-state inactivation curve was S-shaped but not symmetrical.
Abstract: 1. Voltage clamp measurements were performed on single myelinated nerve fibres of the frog Xenopus laevis. 2. During long-lasting depolarizations the potassium current decayed in a fast phase with a time constant of about 0.6 sec and a following slow phase with a time constant between 3.6 (V=0) and 20 sec (V=100 mV). 3. The decay of the potassium current was the result of an inactivation of the potassium permeability and not of a shift of the potassium equilibrium potential as shown by experiments in isotonic KCl solution. 4. At a hyperpolarization of −20 mV the potassium inactivation was fully removed. It remained incomplete even at large depolarizations. The steady-state inactivation curve was S-shaped but not symmetrical. 5. The experimental results could be described by extending the Hodgkin-Huxley equations introducing two terms of potassium inactivation.

77 citations


Journal ArticleDOI
K. Unsicker1
TL;DR: The innervation of the adrenal cortex of the rat and the pig is investigated with the electron microscope and nerve fibers containing synaptic and two types of dense-cored vesicles come into contact with endocrine cells.
Abstract: The innervation of the adrenal cortex of the rat and the pig is investigated with the electron microscope. Nerve fibers containing synaptic and two types of dense-cored vesicles come into contact with endocrine cells. There are no specialized pre- and postsynaptic membranes. The synaptic cleft is about 200 A wide. Generally the basement membrane between nerve and cell is absent. These observations are discussed on the base of more recent experimental findings. Small fibers having an average diameter of about 0.2 to 0.5 μ and containing only tubules and filaments are considered to represent parts of an afferent nervous system.

61 citations


Journal ArticleDOI
W. Bartels1
TL;DR: 5-HT-containing, yellow fluorescent perikarya are to be observed within the nucleus raphes and its neighbourhood, and yellow fluorescent varicosities in the interpeduncular nucleus and in an area between the medial and the lateral septal nucleus.
Abstract: Vorkommen und Verteilung biogener Amine im Gehirn von Rana temporaria-Kaulquappen wurden fluoreszenzmikroskopisch untersucht. Catecholaminhaltige Perikaryen erscheinen ab Stadium 20 im Nucleus reticularis mesencephali, im Tuber cinereum und im Bulbus olfactorius, ab Stadium 22 in den Flugelplatten der Medulla oblongata und in der Area praeoptica. Ab Entwicklungsstufe 20 zeigen sich ventrolateral in Medulla oblongata und Mittelhirn, lateral vom Organon vasculosum hypothalami, im Bereich des medialen Vorderhirnbundels und im Striatum catecholaminhaltige Faseranschwellungen, ab Stadium 22 auserdem in der Eminentia mediana und dem Hypophysenzwischenlappen, in der Commissura transversa (bis zur Stufe 26), in der Commissura anterior (bis zur Stufe 26) und in der Pars ventrolateralis nuclei lateralis septi. Im Striatum ist von dieser Entwicklungsstufe an ein zweites Areal mit grun fluoreszierenden Varikositaten nachweisbar. Ab Stadium 26 finden sich auch in der Pars dorsolateralis des lateralen Septumkerns catecholaminhaltige Faseranschwellungen. Ab Entwicklungsstufe 22 sind 5-HT-haltige, gelb fluoreszierende Perikaryen im Nucleus raphes und in seiner Umgebung zu beobachten, gelb fluoreszierende Varikositaten im Nucleus interpeduncularis und zwischen medialem und lateralem Septumkern.

Journal ArticleDOI
TL;DR: It is concluded that under the present conditions restoration of neuromuscular transmission is accomplished by a re-innervation of the preserved subneural apparatuses of former junctions by regenerating axons.
Abstract: Electron microscopic observations have been made on the regeneration of neuromuscular junctions during spontaneous re-innervation of the rat diaphragm, following unilateral transsection of the phrenic nerve. 3 and 4 weeks after denervation motor end plates displayed the pattern of almost complete degeneration, i.e. persisting subneural foldings, deprived of neural contact and covered with collagen fibrils and fibrocytes. From observations at 5, 10 and 24 weeks after denervation the following sequence of events could be established: a few small axon terminals, accompanied by Schwann cells, became apposed to subneural folds, while most foldings were covered initially by Schwann cells or still by collagen fibrils. Gradually an increasing number of subneural folds came into contact with axon terminals. At 24 weeks all junctions displayed the pattern of a mature motor end plate. In the majority of regenerating neuromuscular junctions single dense-cored vesicles of approximately 900–1200 A were present in axon terminals.

Journal ArticleDOI
03 Feb 1971-Nature
TL;DR: Individual filamentous structures from the phloem exudate of cut cucurbit stems are isolated and the presence of the filaments could be clearly demonstrated after negative staining with the electron microscope.
Abstract: PROTEIN filaments are characteristic structural components of the assimilatory conducting elements of angiosperm plants (“P protein” of Cronshaw and Esau1). We have isolated filamentous structures from the phloem exudate of cut cucurbit stems2. The presence of the filaments could be clearly demonstrated after negative staining with the electron microscope.

Journal ArticleDOI
TL;DR: Biplane videoangiocardiograms of the left ventricle are stored on a video-disc recorder and replayed onto a TV monitor in a stop-action mode and programs are available which allow a simultaneous or successive evaluation of the biplane video-information.

Journal ArticleDOI
TL;DR: The Glandula harderiana des Kaninchens as discussed by the authors is a tubulo-alveolare Druse, e.g., an der medialen und hinteren Wand der Orbita, which besteht aus zwei, makroskopisch unterscheidbaren anteilen: Ein kleinerer oberer Teil ist von weiser farbe, der grosere untere ist rot.
Abstract: 1. Die Glandula harderiana des Kaninchens ist eine tubulo-alveolare Druse. Sie liegt an der medialen und hinteren Wand der Orbita und besteht aus zwei, makroskopisch unterscheidbaren Anteilen: Ein kleinerer oberer Teil ist von weiser Farbe, der grosere untere ist rot. Die sezernierenden Zellen in den tubulosen Endstucken beider Lappen enthalten Fette, die sich mit Scharlachrot und Sudanschwarz B anfarben. Die luminale Oberflache aller Zelltypen farbt sich mit Alcianblau bei pH 2,5 an. 2. Die Drusentubuli beider Lappen sind von einem einschichtigen kubischen bis zylindrischen Epithel ausgekleidet. Die Drusenzellen sind im roten Anteil grosblasig, im weisen Lappen sehr fein vakuolisiert. Das Cytoplasma dieser multilocularen Zellen enthalt freie Ribosomen und eine erstaunlich grose Zahl von Mitochondrien, die meistens eng aneinander lagern. Alle Zellen enthalten ferner mehrere Golgi-Stapel, aber nur sparliche Ergastoplasmamembranen. 3. Die exokrinen Zellen werden an den seitlichen Kontaktflachen durch ein differenziertes Schlusleistennetz (Zonulae occludentes, Zonulae adhaerentes, Desmosomen) verbunden. Die sezernierende Oberflache wird durch die Ausbildung interzellularer Sekretkapillaren vergrosert. 4. Bevor die Fettsubstanzen in die Lichtungen der Drusenschlauche extrudiert werden, kommt es zur Verschmelzung benachbart liegender Pettvakuolen. Die Extrusion wird abgeschlossen durch das Verschmelzen der Hullmembran der Fettvakuolen mit der Plasmamembran, durch Ausbildung einer Offnung in der Plasmamembran und durch das Ausfliesen der Fettsubstanzen. Ein anderer Extrusionsmechanismus besteht darin, das apikal gelegene Fettvakuolen die Zellmembran weit in die Lichtung hinein vorwolben und anschliesend mit einer Hullmembran abgenabelt werden. 5. Terminale Nervenfasern mit bekannter Innenstruktur durchbrechen die Basalmembran und lagern sich den Drusen- oder Myoepithelzellen eng an, teilweise in Vertiefungen ihrer Oberflache eingebettet. Diese terminalen Axone enthalten synaptische Vesikel, Blaschen mit einem massendichten Granulum, Mitochondrien und Neurotubuli. Spezialisierte pra- und postsynaptische Membranen kommen nicht vor.

Journal ArticleDOI
Heiko Braak1
TL;DR: Both nuclei develop a characteristical and homogenous population of pigment granules and possibly the knowledge of the different types of lipofuscin occuring in nerve cells can help to clarify problems of the architectural subdivisions of the brain.
Abstract: The neurolipofuscin of the oliva inferior and nucleus dentatus has been investigated by means of histochemical, and light- and electron microscopical methods. The pigments of both nuclei contain hydrolytic enzymes and can be demonstrated by lipid stains. The PAS-reaction and the performic acid-aldehyde-fuchsin staining give different results. The pigment of oliva inferior is PAS-positive and gives a strong reaction with aldehydefuchsin or astrablue, the pigment of the nucleus dentatus, on the contrary, does not react at all or only faintly. On the electron microscopical level the two types of pigments differ in their shape, diameter, electron density, and composition. It is assumed, that the pigment of oliva inferior consists to a large extent of a sulfur containing melanin-like substance, which is linked with a PAS-positive autoxidised and polymerised lipid component. This compound is lacking in the pigment of the nucleus dentatus or is present only in small amounts.

Journal ArticleDOI
Jörn Thiede1
TL;DR: The coiling direction of Globorotalia species (G. crassaformis, G. truncatulinoides) in sediment cores from the continental slope off Portugal and Morocco varied during the Holocene as mentioned in this paper.

Journal ArticleDOI
TL;DR: The crystal structure of the 1:1 compound TeCl4 · AlCl3 has been determined from three-dimensional X-ray data as mentioned in this paper, which consists of layers composed of strongly distorted TeCl6 octahedra sharing three neighbouring corners with three different AlCl4 tetrahedra.
Abstract: Die 1:1-Verbindung TeCl4 · AlCl3 kristallisiert monoklin in der Raumgruppe P21/c mit a = 6,600, b = 12,675, c = 13,578 A, β = 105,72°, Z = 4. Die Rontgenstrukturanalyse ergab eine Schichtenstruktur. Die Schichten werden von TeCl6-Oktaedern gebildet, die jeweils uber drei benachbarte Ecken mit verschiedenen AlCl4-Tetraedern zu einem zweidimensionalen Netz verbunden sind. Die TeCl6-Oktaeder sind stark verzerrt, die mittleren Abstande TeCl (endst.) betragen 2,276 A, wahrend die Abstande TeCl (Brucke) im Mittel mit 3,061 A sehr viel langer sind. Der Art ihrer Verknupfung entsprechend (uber 3 Ecken mit verschiedenen TeCl6-Polyedern) sind die AlCl4-Tetraeder schwach verzerrt: AlCl-Bindungsabstande: 2,138, 2,142, 2,146 A (Brucke), 2,087 A (endst.). Im polaren Grenzfall ist die Struktur in guter Naherung zu beschreiben als Anordnung von trigonal-pyramidalen TeCl-Ionen und AlCl-Ionen, beide im wesentlichen mit C3v-Symmetrie. Diese Formulierung ist in Ubereinstimmung mit schwingungsspektroskopischen Ergebnissen. The crystal structure of the 1:1 compound TeCl4 · AlCl3 has been determined from three-dimensional X-ray data. The compound crystallizes in space group P21/c with a = 6.600, b = 12.675, c = 13.578 A, β = 105.72°, Z = 4. The structure consists of layers composed of strongly distorted TeCl6 octahedra sharing three neighbouring corners with three different AlCl4 tetrahedra. Mean bond distances are 2.276 A in the TeCl (terminal) bonds and 3.061 A for the TeCl (bridge) bonds. The AlCl tetrahedra, which share one corner with each of three TeCl6 polyhedra, have AlCl distances of 2.087 A (terminal), 2.138, 2.142 and 2.146 A. As a good approximation (in the polar limiting case) the structure can be described as an arrangement of trigonal pyramidal TeCl ions and tetrahedral AlCl ions, both with essentially C3v symmetry. This formulation is in accordance with spectroscopic results.


Journal ArticleDOI
TL;DR: In this article, the ground state energy of the neutral Hubbard model is calculated by BCS methods for all values of total spinSz. Numerical results are given for the simple cubic and for the body centred cubic lattice.
Abstract: The ground state energy of the neutral Hubbard model is calculated by BCS methods for all values of total spinSz. Numerical results are given for the simple cubic and for the body centred cubic lattice. Antiferromagnetic ordering and a finite paramagnetic susceptibility is found for all values of the coupling constantV0.

Journal ArticleDOI
TL;DR: In this article, a millimeter-wave spectrometer has been employed for precise measurements of the millimeter wave rotational spectrum of HCNO, where the ground state and the first excited state of v4 and of v5 were measured.
Abstract: Abstract A newly designed millimeter-wave spectrometer has been employed for precise measurements of the millimeter-wave rotational spectrum of HCNO. Absorptions in several excited vibrational states as well as the ground state could be measured. The present paper presents the observed frequen cies and molecular constants obtained for the ground state and the first excited state of v4 and of v5, the vibrational bending modes

Journal ArticleDOI
TL;DR: Tolerances to temperature, salinity and desiccation are wider in the species of brackish water and less exposed rocky shores, correlating with the greater variations in these conditions where wave action is reduced.
Abstract: Ten sympatric rocky shore species and 3 brackish-water species of Sphaeromatidae were studied. Rocky shores were classified in terms of substrate and exposure to wave action. Although most of the rocky-shore species occur on all shore classes, vertical and horizontal distribution in each species, as well as densities, vary with substrate and wave action. A close relationship between distribution and breeding exists in the rocky-shore species; maximum differences in the vertical distribution of juveniles and adults occur, together with the highest reproductive capacities, in the species exposed to the greatest wave action. Tolerances to temperature, salinity and desiccation are wider in the species of brackish water and less exposed rocky shores, correlating with the greater variations in these conditions where wave action is reduced. Exoskeletons and pereopods are stouter in the species of more exposed shores, except where the microhabitat affords protection from wave action. In Isocladus armatus, geographic and seasonal variations in relative frequencies of colour forms correlate with differences in environmental temperatures. Under laboratory conditions, the colour forms show differences in tolerances to temperature and salinity.

Journal ArticleDOI
TL;DR: Pharmacological evidence for a central component in the regulation of carbohydrate mechanism is presented and the most likely site of action in the CNS is the hypothalamic region which in its turn may activate the anterior pituitary gland.

Journal ArticleDOI
TL;DR: In this article, the Δ1.6-diene-base 12 is hydrogenated only partially to give the Δ 1(6)-base 19 which, on platinum in acetic acid, can be further hydrogenated to a mixture of isomers 8 and 5.
Abstract: Die katalytische Hydrierung des Δ1.6-Dien-lactams 13 mit Platin in Eisessig fuhrt zu den stereoisomeren Lactamen 14 und 15, aus denen durch Reduktion mit Lithiumalanat die cis-und trans-Basen 8 und 5 erhalten werden. Die Δ1.6-Dienbase 12 last sich mit Palladium-Kohle in Methanol nur partiell zur Δ1(6)-Base 19 hydrieren, deren Weiterhydrierung mit Platin in Eisessig ein Gemisch von 8 und 5 liefert. Die Regeln von Prelog fur die katalytische Hydrierung der aromatischen Erythrina-Alkaloide gelten daher fur den ersten Hydrierungsschritt, aber nicht fur den zweiten, der nicht mehr stereospezifisch verlauft. Die cis/trans-Isomerie von 8 und 5 ist durch die Spektren und den Abbau beider Isomeren nach Hofmann bis zum gemeinsamen Endprodukt 27 bewiesen. Durch Spaltung von 5 werden die optischen Antipoden gewonnen, von denen der rechtsdrehende die 5S, 6R-Konfiguration besitzt. Um einen Vergleich mit dem cis-Erythrinan (7) von Belleau durchzufuhren, wird 5 zum trans-Erythrinan (6) abgebaut. Syntheses of Aromatic Erythrina-Alkaloids, XX Synthesis of 15.16-Dimethoxy-trans-erythrinane and its Degradation to trans-Erythrinane Catalytic hydrogenation of the Δ1.6-dien-lactam 13 on platinum in acetic acid yields the stereoisomeric lactams 14 and 15. Reduction with LiAlH4 affords the cis- and trans-bases 8 and 5, respectively. On palladium/carbon in methanol, the Δ1.6-diene-base 12 is hydrogenated only partially to give the Δ1(6)-base 19 which, on platinum in acetic acid, can be further hydrogenated to a mixture of isomers 8 and 5. For the first step. this result is in agreement with Prelog's rules concerning catalytic hydrogenation of aromatic Erythrina alkaloids, whereas the second step is non-stereospecific. 8 and 5 are cis/trans-isomers according to their spectra and Hofmann degradation to the same product 27. Resolution of 5 yields the antipodes. The (+)-compound has 5S, 6R configuration. The trans-crythrinane (6) was prepared by degradation of 5 for purposes of comparison with Belleau's cis-crythrinane (7).

Journal ArticleDOI
TL;DR: Using isolated atria, the positive inotropic action of digitoxin and digoxin was compared quantitatively with the cardiac action of metabolites found in guinea pigs and the bis- and monodigitoxoside of digitoxigenin showed the strongest inotropic effect with respect to the affinity and the maximum response.

Journal ArticleDOI
TL;DR: The hepatic wedge biopsy of a 3 1/2-year-old boy with fucosidosis was studied by electron microscopy and the storage elements appear to be produced by deposition of storage material in lysosomes.
Abstract: The hepatic wedge biopsy of a 3 1/2-year-old boy with fucosidosis was studied by electron microscopy. The cytoplasm of liver parenchymal cells is filled with various forms of membrane-invested storage elements measuring up to 3 μm in diameter. In these storage elements large central deposits of reticulogranular material are surrounded by a narrow peripheral ring of electron-dense material. Others contain numerous lamellar structures with parallel and/or concentric orientation, opaque globules and vesicular structures. Typical peribiliary dense bodies (lysosomes) are generally absent. The storage elements appear to be produced by deposition of storage material in lysosomes. The absence of the lysosomal enzyme α-L-fucosidase is in favor of this concept. Kupffer cells, epithelial cells of the bile canalicular system, vascular endothelial cells of portal tracts and histiocytes are rich in storage elements which are also found in the majority of fibrocytes and fibroblasts. They are uncommon in pericytes and cannot be demonstrated in smooth muscle and fat-storing cells. Ultrastructural features and cellular distribution of storage elements are compared with previous descriptions of related storage disorders.

Journal ArticleDOI
TL;DR: Structural peculiarities ofEpidermal receptor cells of Priapulus caudatus and Rhynchelmis limosella have been investigated with the electron microscope and are interpreted to represent mechanoreceptors because they have the above mentioned structures in common with mechanoreceptor groups of other invertebrate groups.
Abstract: Rezeptoren von Priapulus caudatus und Rhynchelmis limosella werden elektronenmikroskopisch untersucht. Ihre Strukturen stimmen in folgenden Merkmalen uberein: Apikal steht eine Zilie, die von regelmasig angeordneten Mikrovilli umgeben wird. Das Cytoplasma der Mikrovilli ist zentral verdichtet und im ubrigen Bereich von Filamenten ausgefullt, die im Perikaryon wurzeln. Im distalen Teil der Zelle liegt ein reich entwickeltes glattes E. R., darunter folgen Tubuli. Die Zellen werden reich innerviert. Aufgrund der strukturellen Ubereinstimmung mit Mechanorezeptoren anderer Tiergruppen wird den Rezeptoren der untersuchten Formen ebenfalls eine mechanorezeptive Funktion zugeschrieben.


Journal ArticleDOI
Herbert Haug1
TL;DR: In the region of the sulci of the cats brain the membrana limitans gliae superficialis is thicker than in the gyri and contains 3 different kinds of processes of astrocytes.
Abstract: Die Membrana gliae limitans superficialis im Cortex des Gehirns der Katze ist an den Kuppen dunner (herab bis 3 μm) als an den Windungstalern (bis zu 15 μm). Sie enthalt drei verschiedene Fortsatze der Astrocyten, deren Perikarya an der Grenze zum eigentlichen Neuropil der Molekularschicht liegen. Es handelt sich um: 1. Runde oder ovale Fortsatze mit dicht gepackten Gliafilamenten, die horizontal, schrag oder radiar verlaufen. 2. Flache, oberflachliche Fortsatze mit Filamenten (Endfuse). 3. Astrocytenlamellen, d.h. sehr platte, horizontal liegende Fortsatze ohne Filamente, die stapelformig aufeinanderliegen. Eine „specific junction“ wird beschrieben.

Journal ArticleDOI
TL;DR: Dentine and cementum are pyro- and piezoelectric and two well-defined directions of pyroelectric behaviour were demonstrable: in the direction of the longitudinal axis of the tooth—i.e. parallel to the general course of the collagen fibrils—and in the directed direction around the pulp cavity.