Anatomy of Dianthoveus cremnophilus (Cyclanthaceae)

1989 ◽  
Vol 67 (12) ◽  
pp. 3580-3599 ◽  
Author(s):  
George J. Wilder
Keyword(s):  
Boundary Layers ◽  
Cross Section ◽  
Central Cylinder ◽  
Vascular Bundles ◽  
Monotypic Genus ◽  
Ground Tissue ◽  
Intercellular Spaces ◽  
First Order ◽  
Parenchyma Cells ◽  
Order Root

Dianthoveus is a monotypic genus of the Cyclanthaceae and in this paper the anatomy of D. cremnophilus is described, including that of the lamina, petiole, peduncle, rhizome and first-order root. The lamina within interridge areas is hypostomatic and the mesophyll between boundary layers exhibits either two main regions according to sizes of intercellular spaces, or three main regions according to wall thickness of ordinary parenchyma cells. Expansion tissue occurs opposite adaxial and abaxial ridges of the lamina and where the median costa and noncostal portions of lamina are joined together. The petiole exhibits three main zones of ground tissue and the median costa has two to three zones. Certain veins of the petiole compose a conspicuous V in cross section. The peduncle has four main zones of ground tissue, including pith. This organ contains simple vascular bundles (commonly, collateral bundles) and bipolar compound vascular bundles. The rhizome has a conspicuous periderm, cortex (including endodermis), and central cylinder. Diverse forms of vascular bundles occur within the central cylinder, e.g., collateral, amphivasal, compound-tetrapolar, and compound-multipolar. In the first-order root the cortex exhibits various regions, including exodermis and endodermis, and the stele contains peripheral and nonperipheral fascicles, each type of fascicle of either xylem or phloem. Styloid sacs and raphide sacs occur in all and some organs studied, respectively, and in the rhizome and interridge areas of the lamina the styloid sacs are randomly oriented and abundant. Mucilage canals occur in the peduncle and petiole. These anatomical data are used to compare Dianthoveus with other cyclanthaceous genera, particularly Evodianthus.

Permineralized monocotyledons from the Middle Eocene Princeton chert (Allenby Formation) of British Columbia: Alismataceae

1989 ◽  
Vol 67 (9) ◽  
pp. 2636-2645 ◽  
Author(s):  
Diane M. Erwin ◽  
Ruth A. Stockey
Keyword(s):  
British Columbia ◽  
Middle Eocene ◽  
Vascular Bundles ◽  
Western North America ◽  
Ground Tissue ◽  
Abaxial Surface ◽  
Parenchyma Cells ◽  
In Series ◽  
Thin Walled ◽  
Tannin Cells

One small monocotyledon petiole, 1.8 × 1.5 mm wide, has been recovered from the Princeton chert in the Middle Eocene Allenby Formation, British Columbia. The petiole, rectangular in transverse outline, shows approximately 36 circular to oval-shaped vascular bundles within aerenchymatous ground tissue that includes tannin cells. The epidermis is underlain by a discontinuous hypodermis of thick-walled, pitted cells. Vascular bundles are in five series: (I) a median U-shaped arc of 11 – 13 bundles; (II) an abaxial arc of 6 bundles located below the main arc; (III) two short abaxial arcs of 3 bundles each; (IV) 2 bundles just below the abaxial surface; and (V) an adaxial series of 7 bundles that show an inverse orientation to those bundles in series I–IV. Larger bundles are collateral, with a protoxylem lacuna encircled by a ring of 9 – 14 thin-walled parenchyma cells, a relatively well-developed phloem strand, and one to three thin-walled metaxylem elements. Based on bundle arrangement, orientation, and morphology, the fossil petiole most closely resembles those of the Butomaceae and Alismataceae. This new species, Heleophyton helobiaeoides Erwin and Stockey gen. et sp.nov., in the Princeton chert flora, documents the presence of the Alismataceae in the Middle Eocene of western North America and provides further evidence that the locality represents an ancient aquatic ecosystem.

scholarly journals Anatomical investigation of three emergent Cyperus species growing naturally on the canal banks of the Nile delta, Egypt

2017 ◽  
Vol 1 ◽  
pp. 294
Author(s):  
Yasser A. El-Amier ◽  
Ahmed M. Abd El-Gawad
Keyword(s):  
Transverse Section ◽  
Nile Delta ◽  
Bundle Sheath ◽  
Vascular Bundles ◽  
Ground Tissue ◽  
Intercellular Spaces ◽  
Palisade Parenchyma ◽  
Thin Walls ◽  
The World ◽  
Large Genus

The genus Cyperus is a large genus with about 600 species, widespread all over the world. The present work contains anatomical descriptions of culms and leaves anatomy of three taxa of Cyprus spp. (Cyperus alopecuroides, C. articulates and C. papyrus). Cyperus spp. were collected from canal banks of Nile Delta. The culms in transverse section of all examined species were triangular except for C. articulates which was circular. The ground tissue differentiated into parenchyma cells with thin walls and small, triangular intercellular spaces, while C. articulates has large hollow pith. Vascular bundles are small, angular and scattered throughout the thin-walled ground tissue. Leaf anatomy of C. alopecuroides and C. papyrus is an example of the isobilateral mesophyll with palisade parenchyma on both sides, enlarged epidermal cells referred to as hing cells found in the middle of the blade. The center of the leaf is occupied by a large vascular bundle surrounded by a bundle sheath.    

Compression properties of vascular boundles and parenchyma of rattan (Plectocomia assamica Griff)

Holzforschung ◽  
2014 ◽  
Vol 68 (8) ◽  
pp. 927-932 ◽  
Author(s):  
Xing’e Liu ◽  
Genlin Tian ◽  
Lili Shang ◽  
Shumin Yang ◽  
Zehui Jiang
Keyword(s):  
Young’S Modulus ◽  
Cross Section ◽  
Compression Strength ◽  
Young's Modulus ◽  
Vascular Bundles ◽  
Mechanical Compression ◽  
Compression Tests ◽  
Compression Properties ◽  
Parenchyma Cells ◽  
Different Parts

Abstract Rattan is a unique unidirectional vascular bundles-reinforced biocomposite with many nodes along its canes. Mechanical compression tests have been performed from rattan samples taken from different parts of the cross section. Compression strength increased with increasing amounts of vascular bundles (VBs) in the tissues was investigated. Samples including the outer ring with many VBs have the highest apparent Young’s modulus of 1.08 GPa and the highest compression strength of 17.6 MPa. However, samples consisting of parenchyma cells had an apparent Young’s modulus of 25 MPa, and the compression strength of 1.81 MPa. The compression properties of core samples improved with increasing amounts of VB. The apparent Young’s modulus and compression strength of a single VB were 730 MPa and 6.87 MPa, respectively, and were calculated according to the rule of mixture of composites.

scholarly journals The influence of two morphactins on forming of tissues in sunflower (Helianthus annuus L.) stem

2013 ◽  
Vol 35 (2) ◽  
pp. 175-183
Author(s):  
J. Kostrzewska-Kuczumow ◽  
E. Weryszko ◽  
A. Tomaszewski
Keyword(s):  
Helianthus Annuus ◽  
Considerable Increase ◽  
Central Cylinder ◽  
Vascular Bundles ◽  
Tissue Formation ◽  
Histological Changes ◽  
Water Solutions ◽  
Helianthus Annuus L ◽  
Parenchyma Cells ◽  
Different Types

The influence of two morphactins (IT 3233 and IT 3456) on tissue formation in sunflower stem was studied. The seeds were wetted with water solutions of morphactins in concentrations of 10 ppm and 50 ppm. The stems of the treated plants were thinner and they had less nodes. The diminution of stem thickness took place as a result of the decrease of central cylinder parenchyma cells in size. There also appeared histological changes in the composition of vascular bundles. The diminution of the number of bundles was ascertained together with an increase of their size. Arched intrabundle cambium and xylem exhibited an inclination to partial surrounding of phloem. A considerable increase of the number oftracheal elements was observed. Their diameter was much smaller. Spiral vessels and tracheids arose after treatment with IT 3456 10 ppm. Different types of vessels appeared in the remaining combinations. The disruption and obliteration of many vessels of protoxylem and also disruption of the parenchyma adhesing to them took place.

scholarly journals Histopathology of Red Stripe of Rice

Plant Disease ◽  
2004 ◽  
Vol 88 (12) ◽  
pp. 1304-1309 ◽  
Author(s):  
Hisatoshi Kaku
Keyword(s):  
Bacterial Infection ◽  
Histological Study ◽  
Vascular Bundles ◽  
Bacterial Cells ◽  
Intercellular Spaces ◽  
Early Appearance ◽  
Vessel Walls ◽  
Dark Blue ◽  
Causal Bacterium

A histological study of red stripe of rice was conducted to elucidate the mode of infection of the causal bacterium Microbacterium sp. When pin-point-sized spots first appeared at 3 days after inoculation, the bacterial cells had entered through stomata and multiplied in the intercellular spaces of substomatal parenchymatous tissues. With the early appearance of small yellow spots at 4 to 5 days after inoculation, the bacterium was detected in some xylem vessels as well as in parenchymatous tissues, and it had apparently translocated directly from parenchymatous tissues to transverse vascular systems through spiral vessel walls. With the appearance of typical red stripe symptoms comprised of orange lesions and halos at 8 days after inoculation, bacterial masses were present in transverse and longitudinal vascular bundles in areas with orange lesions. In the areas with orange to light brown spots, granules that stained dark blue using Stoughton's method appeared in the protoplasm of the host parenchymatous cells, which later became necrotic. In halo areas, bacterial masses were observed only in some cases, and chloroplasts were disorganized. Bacterial infection was also confirmed by observing sections of naturally infected samples, and the distribution of bacteria was much more extensive than in artificially inoculated samples.

Natural frequencies of parabolic arches with a single crack on opposite cross-section sides

2019 ◽  
Vol 25 (7) ◽  
pp. 1313-1325 ◽  
Author(s):  
U Eroglu ◽  
G Ruta ◽  
E Tufekci
Keyword(s):  
Cross Section ◽  
Natural Vibration ◽  
Natural Frequencies ◽  
Damage Identification ◽  
Crack Opening ◽  
Curved Beams ◽  
Governing Equations ◽  
First Order ◽  
Crack Location ◽  
Original Contribution

We study natural vibration of elastic parabolic arches, modeled as plane curved beams susceptible to elongation, shear, and bending, exhibiting small concentrated cracks. The crack is simulated by springs between regular chunks, with stiffness evaluated following stress concentration in usual crack opening modes. We evaluate and compare the linear dynamic response of the undamaged and damaged arch in nondimensional form. The governing equations are turned into a system of first-order differential equations that are solved numerically by the so-called matricant. The original contribution of this study lies in highlighting the dependence of the variation of the first natural frequencies on the crack location not only along the axis but also on opposite sides of the cross-section. We obtain the relative variations of the first frequencies in terms of the two crack locations. The result of this direct problem provides information on the possibility to detect such locations, and gives indications on structural monitoring and damage identification.

DEVELOPMENTAL STUDIES OF THE APPLE FRUIT IN THE VARIETIES McINTOSH RED AND WAGENER: II. AN ANALYSIS OF DEVELOPMENT

1941 ◽  
Vol 19c (10) ◽  
pp. 371-382 ◽  
Author(s):  
Mary MacArthur ◽  
R. H. Wetmore
Keyword(s):  
Cell Division ◽  
Cell Size ◽  
Fruit Size ◽  
Apple Fruit ◽  
Vascular Bundles ◽  
Developmental Studies ◽  
Cell Enlargement ◽  
Ground Tissue ◽  
Fundamental Pattern

Growth in the various tissues of the fruit of a McIntosh Red and a Wagener tree, both self-pollinated, is compared. For several days succeeding pollination no increase in fruit size is apparent. Fertilization is followed by general cell division and cell enlargement. The period of cell division varies with the tissue and with the variety. Final cell size is reached first by the cells of those tissues near the centre of the apple. Impressed upon the fundamental pattern of growth is the localized activity of the primary vascular bundles, the cambia of which add cells to the ground tissue. Angulation in the Wagener is accentuated by this activity. With the exception of cells of the epidermis, final cell size is approximately equal in comparable regions of the two varieties. Differences in regional extent are due to differences in numbers of cells in that region.

The Myocardial Signature: Absolute Backscatter, Cyclical Variation, Frequency Variation, and Statistics

1986 ◽  
Vol 8 (2) ◽  
pp. 107-120 ◽  
Author(s):  
T. L. Rhyne ◽  
K. B. Sagar ◽  
S. L. Wann ◽  
G. Haasler
Keyword(s):  
Fine Structure ◽  
Cross Section ◽  
Rayleigh Scattering ◽  
Cardiac Cycle ◽  
Frequency Variation ◽  
Myocardial Ultrastructure ◽  
Order Model ◽  
Integrated Backscatter ◽  
Cyclical Variation ◽  
First Order

This paper studies the absolute myocardial backscatter as a function of the frequency and phase of the cardiac cycle. This was achieved by calibration of the ultrasonic instrumentation and the random diffraction process. We have discovered a first-order model in which the scattering from the myocardium is Rayleigh scattering with a cardiac cycle variation in the scattering cross section. Furthermore, the statistics are approximately those of a radio frequency waveform with two independent Gaussian components (Rayleigh envelope). Deviations from the first-order model suggest measurable fine structure related to myocardial ultrastructure. This model has profound effects on the choice of optimal radiation patterns and signal processing schemes for preparing diagnostic parameters (e.g., integrated backscatter).

Vibration Characteristics of Straight Blades of Asymmetrical Aerofoil Cross-Section

1969 ◽  
Vol 20 (2) ◽  
pp. 178-190 ◽  
Author(s):  
W. Carnegie ◽  
B. Dawson
Keyword(s):  
Analytical Solution ◽  
Cross Section ◽  
Natural Frequencies ◽  
Equations Of Motion ◽  
Limited Range ◽  
First Order ◽  
Special Cases ◽  
Theoretical Results ◽  
Theoretical Procedure ◽  
Good Agreement

SummaryTheoretical and experimental natural frequencies and modal shapes up to the fifth mode of vibration are given for a straight blade of asymmetrical aerofoil cross-section. The theoretical procedure consists essentially of transforming the differential equations of motion into a set of simultaneous first-order equations and solving them by a step-by-step finite difference procedure. The natural frequency values are compared with results obtained by an analytical solution and with standard solutions for certain special cases. Good agreement is shown to exist between the theoretical results for the various methods presented. The equations of motion are dependent upon the coordinates of the axis of the centre of flexure of the beam relative to the centroidal axis. The effect of variations of the centre of flexure coordinates upon the frequencies and modal shapes is shown for a limited range of coordinate values. Comparison is made between the theoretical natural frequencies and modal shapes and corresponding results obtained by experiment.

Absolute cross section of first-order Raman scattering in GaAs

1979 ◽  
Vol 20 (4) ◽  
pp. 1758-1761 ◽  
Author(s):  
M. H. Grimsditch ◽  
D. Olego ◽  
M. Cardona
Keyword(s):  
Raman Scattering ◽  
Cross Section ◽  
Absolute Cross Section ◽  
First Order
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