Stationary Operated Lithium In-Vessel Elements of a Tokamak

Initiation of vessel formation and vessel maturation indicated by secondary wall deposition have been compared in eleven deciduous broadleaved tree species. In ring-porous species the first vessel element formation in the current growth ring was initiated two to six weeks prior to the onset of leaf expansion, and secondary wall deposition on the vessel elements was completed from one week before to three weeks after leaf expansion. In diffuse-porous species, the first vessel element formation was initiated two to seven weeks after the onset of leaf expansion, and secondary wall deposition was completed four to nine weeks after leaf expansion. These results suggest that early maturation of the first vessel elements in the ring-porous species will serve for water conduction in early spring. On the contrary, the late maturation of the first vessel elements in the diffuse-porous species indicates that no new functional vessels exist at the time of the leaf expansion.

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Development of cambium and length of vessel elements and fibers in dwarfAlnus hirsuta (Spach) rupr

Journal of Plant Biology ◽

10.1007/bf03030455 ◽

1997 ◽

Vol 40 (4) ◽

pp. 245-248 ◽

Cited By ~ 2

Author(s):

Dong Ok Lim ◽

Woong Young Son

Keyword(s):

Vessel Elements

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CARACTERIZAÇÕES ANATÔMICA E FÍSICO-MECÂNICA DA MADEIRA DE Liquidambar sp.

FLORESTA ◽

10.5380/rf.v45i4.36878 ◽

2015 ◽

Vol 45 (4) ◽

pp. 723 ◽

Cited By ~ 2

Author(s):

Thaís Pereira Freitas ◽

Lairo David Feuchard ◽

José Tarcísio Silva Oliveira ◽

Juarez Benigno Paes ◽

Marina Donária Chaves Arantes

Keyword(s):

Specific Gravity ◽

Dimensional Stability ◽

Mechanical Characterization ◽

Great Influence ◽

Low Frequency ◽

Ground Level ◽

Espírito Santo ◽

Vessel Elements ◽

Espirito Santo

Este trabalho teve como objetivo a caracterização anatômica e físico-mecânica da madeira de Liquidambar sp. Para tanto, foram utilizadas três árvores com oito anos de idade, provenientes de um arboreto localizado do município de Guaçuí, Espírito Santo. As características anatômicas analisadas foram as dimensões das fibras (comprimento, diâmetro total e do lume e espessura da parede), dos elementos de vasos (diâmetro tangencial e frequência) e dos raios (altura, largura e frequência). Para a caracterização físico-mecânica foram avaliadas a massa específica (básica, aparente a 12% de umidade e anidra), as contrações totais lineares e volumétrica, a resistência à flexão estática, à compressão paralela às fibras, ao cisalhamento e dureza Janka. Constatou-se frequência vascular numerosa com vasos de pequeno diâmetro tangencial, raios heterocelulares ocorrendo em baixa frequência, e fibras libriformes longas de paredes delgadas a espessas. A massa específica básica da madeira proveniente de discos retirados a 1,30 m do nível do solo foi de 0,48 g cm-3, sendo considerada média, a estabilidade dimensional foi considerada baixa, e houve grande influência da umidade nos valores de resistência da madeira. AbstractAnatomical and physical-mechanical characterization of Liquidambar sp. wood. This research aimed to improve anatomical, physical and mechanical characterization of Liquidambar sp.wood. Three trees were obtained, at eight years of age, from an arboretum located in Guaçuí, Espírito Santo State, Brazil. The analyzed variables were dimensions of the fibers (length, total diameter and diameter of the lumen and wall thickness), the vessel elements (tangential diameter and frequency), and ray (height, width and frequency). The specific gravity (basic, at 12% moisture content and dry), and total volumetric and linear shrinkages, resistance to bending, compression parallel to the fibers, shear and Janka hardness. For anatomical description it was found numerous vessels often with small tangential diameter, heterocellular rays occurring at low frequency, and long libriform fibers with thick to thin walls. The specific gravity of wood from disks taken at 1.30 m from ground level was 0.48 g cm-3, wich we considered average, the dimensional stability was low, and there was great influence of moisture in the resistance values in wood.Keywords: Anatomy; specific gravity; dimensional stability; mechanical strength.

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Anatomia da madeira de Colletia paradoxa (Spreng.) Escalante

Ciência e Natura ◽

10.5902/2179460x25024 ◽

1983 ◽

Vol 5 (5) ◽

pp. 161

Author(s):

José Newton Cardoso Marchiori

Keyword(s):

Wood Anatomy ◽

Small Diameter ◽

Rio Grande ◽

Rio Grande Do Sul ◽

Microscopic Anatomy ◽

Physiological Aspect ◽

Anatomical Features ◽

Vessel Elements ◽

Ray Cells ◽

Perforation Plates

This paper deals with the description of general, macroscopic and microscopic anatomy of Colletia paradoxa (Spreng.) Escalante, an aphyllous and xerophilous shrub from Rio Grande do Sul (Brazil). Pores of very small diameter, very short vessel elements, spiral thickenings and simple perforation plates in vessels, non sptate libriform fibers, scanty paratracheal axial paranchyma, and Heterogeneous II rays were observed in the wood.. Perforated cells are also common in rays. The presence of perforated ray cells and anatomical features of the vessel elements are discussed with respect to eco-physiological aspect of the plant and wood anatomy literature.

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Using cell cross-section dimensions and digital image correlation to evaluate drying shrinkage and collapse in Eucalyptus nitens wood

BioResources ◽

10.15376/biores.15.3.6149-6164 ◽

2020 ◽

Vol 15 (3) ◽

pp. 6149-6164

Author(s):

Alan Dickson ◽

Bernard Dawson

Keyword(s):

Digital Image Correlation ◽

Cross Section ◽

Digital Image ◽

Laser Scanning ◽

Drying Shrinkage ◽

Laser Scanning Microscopy ◽

Image Correlation ◽

Confocal Laser ◽

Eucalyptus Nitens ◽

Vessel Elements

An approach combining maps of wood morphology and digital image correlation was developed to investigate the drying of Eucalyptus nitens wood. Maps of morphological features (vessel and ray distribution) and cell cross-section dimensions were acquired by confocal laser scanning microscopy. Shrinkage maps were generated using digital image correlation. There were statistically significant correlations between shrinkage/collapse and wood morphology at two levels. Firstly, there were positional relationships, with for example, both radial and tangential shrinkage increasing with increasing distance from vessel elements. Secondly, there were dimensional relationships, such as, cells with large perimeters (relative to their wall thickness) on average showing greater shrinkage. Generally, the positional relationships dominated the dimensional relationships. Detailed analysis over large areas allows for a fuller analysis of the interrelationship between wood morphology and drying shrinkage and collapse.

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An Approach to the study of vessels climber species

FLORA AND FAUNA ◽

10.33451/florafauna.v26i1pp15-21 ◽

2020 ◽

Vol 26 (1) ◽

Author(s):

R.R. Khandagale ◽

B.K. Auti

Keyword(s):

Middle Part ◽

Line Drawings ◽

Plant Soil ◽

Vessel Elements ◽

Specialized Tissue ◽

Large Perforation ◽

Perforation Plates ◽

And Storage ◽

Soil Interface ◽

Highly Evolved

The angiosperms are characterized by vessels in wood, and therefore, vessel elements were selected to study them in climber species. Xylem is the specialized tissue that transports water and nutrients from the plant–soil interface to stem and leaves and provides mechanical support and storage. Water is the primary solvent for plant nutrition and metabolism and is essential for photosynthesis, turgor and for transport of minerals, hormones and other molecules. Studies on vessels showed that the characters of vessels can throw some light on the phylogeny of species. The short vessel members with many perforation plates with a single large perforation are most specialized and those that were long with elongate obliquely placed perforation plates with many perforations separated by bars that together give a scalariform appearance are primitive. The degree of specialization of vessel elements can be measured in terms of vessel length, breadth and the number of bars on the end plate of vessels. Vessels show highly evolved and primitive vessel elements. Mostly elongated vessel elements are present in middle region of the stem. During this study the broadest vessels were found in the middle part of the stem of dicots (Clitoria, Daemia and Aristolochia) and root of the monocots (Gloriosa) and the narrowest vessel elements were found in different parts of the species investigated. The present work is supported with line drawings of prepared stained sections, provides a framework of the vessels. This study will be very useful to a wideseries of community, who work with plants.

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Resistance of hardwood vessels to degradation by white rot Basidiomycetes

Canadian Journal of Botany ◽

10.1139/b88-251 ◽

1988 ◽

Vol 66 (9) ◽

pp. 1841-1847 ◽

Cited By ~ 38

Author(s):

Robert A. Blanchette ◽

John R. Obst ◽

John I. Hedges ◽

Karen Weliky

Keyword(s):

Cell Wall ◽

Secondary Wall ◽

White Rot ◽

Fungal Decay ◽

Acacia Koa ◽

Monomer Composition ◽

Lignin Removal ◽

Vessel Elements ◽

Parenchyma Cells ◽

Unusual Type

White stringy rot, an unusual type of selective fungal decay, can be found in wood of some dicotyledonous angiosperms. Stages of advanced decay consist of a mass of vessel elements with only remnants of other cells adhering to the vessel walls. Degradation by various white rot Basidiomycetes causes loss of fibers, fiber tracheids, and parenchyma cells but not vessels. In wood of Acacia koa var. koa with a white pocket rot caused by Phellinus kawakamii, fibers and parenchyma cells were preferentially delignified. After extensive lignin removal the cellulose remaining in the secondary wall was degraded. Large vessel elements remained relatively intact after other cells were completely degraded. The resistance of vessels to degradation appears to be due to their high ligninxarbohydrate ratio, lignin monomer composition, and cell wall morphology.

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Mucilaginous Secretions in the Xylem and Leaf Apoplast of the Swamp Palm Mauritia flexuosa L.f. (Arecaceae)

Microscopy and Microanalysis ◽

10.1017/s1431927620001543 ◽

2020 ◽

Vol 26 (3) ◽

pp. 609-621

Author(s):

Alessandra Flávia Silveira ◽

Maria Olívia Mercadante-Simões ◽

Leonardo Monteiro Ribeiro ◽

Yule Roberta Ferreira Nunes ◽

Lucienir Pains Duarte ◽

...

Keyword(s):

Cell Wall ◽

Cell Wall Polysaccharides ◽

Anatomical Structures ◽

Carboxylate Groups ◽

Medicinal Value ◽

Mauritia Flexuosa ◽

Vessel Elements ◽

Wall Loosening ◽

Sclerenchyma Fibers ◽

Leaf Apoplast

AbstractMauritia flexuosa palms inhabit wetland environments in the dry, seasonal Brazilian savanna (Cerrado) and produce mucilaginous secretions in the stem and petiole that have a medicinal value. The present study sought to characterize the chemical natures of those secretions and to describe the anatomical structures involved in their synthesis. Chemical analyzes of the secretions, anatomical, histochemical analyses, and electron microscopy studies were performed on the roots, stipes, petioles, and leaf blades. Stipe and petiole secretions are similar, and rich in cell wall polysaccharides and pectic compounds such as rhamnose, arabinose, xylose, mannose, galactose, and glucose, which are hydrophilic largely due to their hydroxyl and carboxylate groups. Mucilaginous secretions accumulate in the lumens of vessel elements and sclerenchyma fibers of the root, stipe, petiole, and foliar veins; their synthesis involves cell wall loosening and the activities of dictyosomes. The outer faces of the cell walls of the parenchyma tissue in the mesophyll expand to form pockets that rupture and release pectocellulose substances into the intercellular spaces. The presence of mucilage in the xylem, extending from the roots to the leaf veins and continuous with the leaf apoplast, and sub-stomatal chambers suggest a strategy for plant water economy.

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Lignin Distribution in Coppice Poplar, Linseed and Wheat Straw

Holzforschung ◽

10.1515/hf.2001.063 ◽

2001 ◽

Vol 55 (4) ◽

pp. 379-385 ◽

Cited By ~ 65

Author(s):

Lloyd Donaldson ◽

Jamie Hague ◽

Rebecca Snell

Keyword(s):

Wheat Straw ◽

Secondary Wall ◽

Middle Lamella ◽

Laser Scanning Microscopy ◽

Interference Microscopy ◽

Confocal Laser ◽

Lignin Concentration ◽

Lignin Distribution ◽

Vessel Elements ◽

Parenchyma Cells

Summary Lignin distribution was determined by interference microscopy, and by confocal laser scanning microscopy (CLSM) for a range of agricultural residues including coppice poplar, linseed, and wheat straw. Interference microscopy was used to determine the lignin concentration in the middle lamella at the cell corner, and for the secondary wall of libriform fibres in the secondary xylem of poplar and linseed. Wheat was examined in the same way for cortical fibres. In addition the secondary wall of vessel elements was examined for poplar. Confocal microscopy was used to confirm the results from interference microscopy by providing semiquantitative information based on lignin autofluorescence, and by staining with acriflavine. Wheat had the lowest level of lignification, with 31 % lignin in the middle lamella of cortical fibres and 9% lignin in the secondary wall. Poplar had a lignin concentration of 63% in the middle lamella and 6% in the secondary wall of libriform fibres, while linseed had corresponding values of 69 % and 13 %. The secondary wall of poplar vessel elements had a lignin concentration of 25 %. In all three species most of the stem tissue was lignified except for phloem and bark, where present. In linseed the pith was unlignified. In wheat, most of the parenchyma cells were lignified except for a few cells lining the stem cavity. Libriform fibres in poplar and linseed sometimes had an unlignified gelatinous layer in samples containing tension wood. In linseed, lignification was greater in xylem fibres compared to bast fibres. Ray parenchyma cells of poplar and linseed appeared to be lignified to the same extent as xylem fibres.

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