scholarly journals Anatomía de la madera de especies arbóteas de un bosque mesófilo de montaña: un enfoque ecológico-evolutivo

2017 ◽  
pp. 51 ◽  
Author(s):  
Silvia Aguilar-Rodríguez ◽  
Josefina Barajas-Morales
Keyword(s):  
Cloud Forest ◽  
Point Of View ◽  
Type I ◽  
Growth Rings ◽  
Ecological Wood Anatomy ◽  
Thin Walls ◽  
Vessel Elements ◽  
Bosque Mesófilo De Montaña ◽  
Perforation Plates ◽  
Long Fibers

In order to investigate trends in ecological wood anatomy of a cloud forest, 29 tree species from Ocuilan, State of Mexico, were studied. The results suggest that the homogeneous climate of the area determines the absence of growth rings for most species; also, a narrow relationship was observed between rings and the phytogeographic origin of taxa. With respect to the remaining anatomical characters, there is a high percentage of wood with diffuse porosity; also, medium and long vessel elements are common, with small diameters and scalariform perforation plates, along with long fibers with thin walls, of libriform type, or fibrotracheids in which septs may be present or not; axial parenchym is scarce and rays are heterogeneous, of type I. These characters are discussed from an ecological and evolutionary point of view.

scholarly journals Estudo anatômico da madeira de Myrceugenia glaucescens (Camb.) Legr. et Kaus

1988 ◽  
Vol 10 (10) ◽  
pp. 105 ◽  
Author(s):  
José Newton Cardoso Marchiori ◽  
Graciela I. Bolzon Muñiz
Keyword(s):  
Microscopic Structure ◽  
Type I ◽  
Common Occurrence ◽  
Anatomical Data ◽  
Vessel Elements ◽  
Perforation Plates ◽  
Vestured Pits

The general and minute wood features of Myrceugenia glaucescens are described. Anatomical data and photomicrographs of the wood are presented. The microscopic structure of the wood is compared with references of the species, genus and family Myrtaceae found in literature. The most important characters observed in the wood are the occurrence of perforation plates varying from simples to scelariform and reticulate, vessel-ray pits radially elongated, spiral thickenings in vessel elements and in the relatively scarce vasicentric tracheids. The presence of Heterogeneous type-I rays, vestured pits, very long vessel elements, apotracheal parenchyma, fibre tracheids and solitary pores, are also important features of this wood and of common occurrence in Myrtaceae.

Ecological Wood Anatomy of the Woody Southern Californian Flora

IAWA Journal ◽  
1985 ◽  
Vol 6 (4) ◽  
pp. 319-347 ◽  
Author(s):  
Sherwin Carlquist ◽  
David A. Hoekman
Keyword(s):  
Southern California ◽  
Woody Species ◽  
Adaptive Strategy ◽  
Vessel Diameter ◽  
Vessel Element ◽  
Growth Rings ◽  
Desert Shrubs ◽  
Perforation Plate ◽  
Vessel Elements ◽  
Perforation Plates

Wood of 207 species, representing all 178 woody genera of the Munz flora of southern California, was studied by means of sections and macerations. Data were gathered on features relating to the conducting system: number of vessels per mm2, diameter of vessels, length of vessel elements, number of bars per perforation plate, presence of true tracheids, vasicentric tracheids, vascular tracheids, helical sculpture, and growth rings. The occurrence of these features is analysed both with respect to each other and to ecological groupings and habit groupings. Statistically significant data permit ecological groupings to demonstrate degree of xeromorphy in wood features. Xeromorphy is indicated by more numerous vessels per mm2, narrow vessels, shorter vessel elements, presence of vasicentric tracheids or vascular tracheids, presence of helical sculpture on vessel walls, and presence of well-marked growth rings (growth rings are common in moist habitats because in southern California these are also montane and therefore cold in winter). All of these appear to have developed in many phylads independently. Vessel element length appears to change less rapidly, at least in some phylads (those with true tracheids) than the other features. Presence of scalariform perforation plates and of true tracheids is interpreted as relictual; scalariform plates occur virtually only in mesic habitats and in a small number of species. True tracheids, although relictual in nature, have been preferentially preserved because of the value of their enormous safety. Groups without true tracheids have evolved vasicentric tracheids or vascular tracheids (the three types are mutually exclusive) to a high degree. By deducting the species with true and vascular tracheids, one finds that 100% of the alpine shrubs, 77% of the desert shrubs, and 75% of the chaparral shrubs which could possibly have evolved vasicentric tracheids actually have them. These are the three ecological groupings which have vasicentric tracheids not only in southern California, but other areas of the world as well. Tracheid presence (and to a lesser extent vasicentric tracheid presence) forestalls vessel grouping, but in tracheid-free groups vessel grouping is a highly adaptive strategy for xeromorphy. One can rank xeromorphic connotation of qualitative features on the basis of data herein: growth rings are the most common numerically, followed by helical sculpture, vasicentric tracheids, and vascular tracheids. Vasicentric tracheids, like true tracheids, tend to occur in evergreen shrubs whereas vascular tracheids tend to be related to drought-deciduous shrubs. Among quantifiable features, number of vessels per mm2 changes more rapidly than vessel diameter. Scalariform perforation plates, true tracheid presence, and long vessel elements are associated with each other statistically . By entering number of woody species for each genus in the flora and performing appropriate computations, a figure for each feature is projected on the basis of the 512 woody species of southern California. This pro-rated figure shows that phylads with any of the mechanisms cited as signifying xeromorphy speciate much more rapidly than do the phylads with mesomorphic wood features.

scholarly journals Immunological Aspects Related to Viral Infections in Severe Asthma and the Role of Omalizumab

Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 348
Author(s):  
Francesco Menzella ◽  
Giulia Ghidoni ◽  
Carla Galeone ◽  
Silvia Capobelli ◽  
Chiara Scelfo ◽  
...  
Keyword(s):  
Innate Immunity ◽  
Severe Asthma ◽  
Viral Infections ◽  
Respiratory Infections ◽  
Antiviral Effect ◽  
Point Of View ◽  
Type I ◽  
Effector Cells ◽  
Viral Spread ◽  
Increased Risk

Viral respiratory infections are recognized risk factors for the loss of control of allergic asthma and the induction of exacerbations, both in adults and children. Severe asthma is more susceptible to virus-induced asthma exacerbations, especially in the presence of high IgE levels. In the course of immune responses to viruses, an initial activation of innate immunity typically occurs and the production of type I and III interferons is essential in the control of viral spread. However, the Th2 inflammatory environment still appears to be protective against viral infections in general and in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections as well. As for now, literature data, although extremely limited and preliminary, show that severe asthma patients treated with biologics don’t have an increased risk of SARS-CoV-2 infection or progression to severe forms compared to the non-asthmatic population. Omalizumab, an anti-IgE monoclonal antibody, exerts a profound cellular effect, which can stabilize the effector cells, and is becoming much more efficient from the point of view of innate immunity in contrasting respiratory viral infections. In addition to the antiviral effect, clinical efficacy and safety of this biological allow a great improvement in the management of asthma.

Structural diversity of the wood of temperate species of Acacia s.s. (Leguminosae: Mimosoideae)

2013 ◽  
Vol 61 (4) ◽  
pp. 291 ◽  
Author(s):  
Frances Whinder ◽  
Kerri L. Clarke ◽  
Nigel W. M. Warwick ◽  
Peter E. Gasson
Keyword(s):  
New South ◽  
Structural Diversity ◽  
Consistent Difference ◽  
Growth Rings ◽  
Axial Parenchyma ◽  
South Wales ◽  
Great Utility ◽  
Australian Continent ◽  
Qualitative Characters ◽  
Perforation Plates

Acacia s.s. comprises approximately 1020 species (i.e. just under one-third of all mimosoid legumes) and is almost entirely restricted to, although widespread, on the Australian continent. We investigated variation in the wood anatomy of 12 species from temperate New South Wales in a study concentrating on four recognised taxonomic sections (Botrycephalae, Juliflorae, Phyllodineae and Plurinerves), to elucidate which characteristics are consistent within the sections, having removed climatic effect as much as possible. The sections had great utility in species identification, whereas none of the wood characters reflected the hypothesised phylogeny of the genus. The main consistent difference among species was in ray width (uniseriate versus 1–3 cells wide). All species had distinct growth rings. The vessels had alternate vestured pitting and simple perforation plates. Fibres were generally thick-walled, and many fibres had a gelatinous inner wall (tension wood fibres) and were inconsistently distributed. Axial parenchyma was mainly paratracheal, ranging from vasicentric to confluent and varied greatly in abundance. Prismatic crystals were usually present in chambered fibres and axial parenchyma strands, and also varied in abundance. The variation in these qualitative characters obscures taxonomic differences, but may allow inferences to be made about environmental adaptation.

scholarly journals PREVISÕES TECNOLÓGICAS NA MADEIRA DE QUATRO FOLHOSAS NEOTROPICAIS: UMA ANÁLISE SOB ENFOQUE ANATÔMICO

Nativa ◽  
2018 ◽  
Vol 6 (1) ◽  
pp. 107
Author(s):  
Talita Baldin ◽  
Maiara Talgatti ◽  
José Newton Cardoso Marchiori ◽  
Amanda Grassmann Da Silveira
Keyword(s):  
Standard Technique ◽  
Sao Paulo ◽  
São Paulo ◽  
Black Forest ◽  
Specific Mass ◽  
Growth Rings ◽  
Wood Technology ◽  
Scientific Institutions ◽  
Perforation Plates ◽  
Radial Arrangement

Baseando-se na descrição anatômica de três espécies de Calycophyllum, sendo elas Calycophyllum candidissimum, Calycophyllum multiflorum e Calycophyllum spruceanum e uma variedade Calycophyllum spruceanum f. brasiliensis, pretende-se inferir sobre o comportamento da madeira, e, ao mesmo tempo atribuir, ainda que empiricamente, um uso adequado ao material. As amostras analisadas são provenientes de diferentes instituições científicas, tais como o Jodrell Laboratory (Kew Gardens, Londres), o Instituto de Pesquisas Tecnológicas do Estado de São Paulo (IPT) e a Universidade alemã Black Forest Academy (BFA). Para a obtenção de lâminas histológicas e de macerado utilizou-se respectivamente, a técnica padrão e o método de Franklin modificado. As descrições anatômicas seguiram as recomendações do IAWA Committee. As espécies compartilham os seguintes caracteres: anéis de crescimento distintos; poros em arranjo radial e de paredes espessas; porosidade difusa; placas de perfuração simples; pontoações intervasculares pequenas, ornamentadas; parênquima axial ausente; raios heterocelulares; e fibras libriformes septadas, de comprimento médio, com paredes delgadas a espessas. É pressuposto que as características anatômicas do lenho das espécies investigadas, conferem à madeira uma alta massa específica, resistência a esforços mecânicos, alta contração volumétrica, permeabilidade e boa durabilidade natural.Palavra-chave: tecnologia da madeira, anatomia do lenho, Rubiaceae. TECHNOLOGICAL PREDICTIONS ON THE WOOD OF FOUR AMAZONIAN HARDWOOD:  AN EVALUATION UNDER ANATOMIC APPROACH ABSTRACT:Based on the anatomic description of three species of Calycophyllum being them Calycophyllum candidissimum, Calycophyllum multiflorum and Calycophyllum spruceanum and one variety of Calycophyllum spruceanum f. brasiliensis, it is intended to infer the wood performance, and assign a proper use to the material, even though empirically. The studied samples come from different scientific institutions, such as Jodrell Laboratory (Kew Gardens, London), Institute for Technological Research (São Paulo, Brazil) and the Black Forest Academy (BFA), Germany. To obtain histological slides and from macerated, the standard technique and the modified Franklin method were used, respectively. The anatomic descriptions followed the IAWA Committee recommendations. The species have the followings characteristics in common: distinct growth rings; pores in radial arrangement and thick walls; diffuse porosity; simple perforation plates; pits small intervessel, ornamented; absent axial parenchyma; heterocell rays; and libriform chambered fiber, medium length, with thin and thick walls. It is assumed that the anatomical characteristics of the wood of the investigated species, confer the wood a high specific mass, resistance to mechanical stress, hight shrinkage, permeability and good natural durability.Keywords: wood technology, wood anatomy, Rubiaceae. DOI:

scholarly journals Anatomia da madeira de Colletia paradoxa (Spreng.) Escalante

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.

scholarly journals Florística del bosque mesófilo de montaña de Molocotlán, Molango-Xochicoatlán, Hidalgo, México

2017 ◽  
pp. 101
Author(s):  
Rafael Mayorga-Saucedo ◽  
Isolda Luna-Vega ◽  
Othón Alcántara-Ayala
Keyword(s):  
Cloud Forest ◽  
Sierra Madre Oriental ◽  
Sierra Madre ◽  
Present Distribution ◽  
Bosque Mesófilo De Montaña

The cloud forest of Molocotlán indudes part of two municipalities of the Hidalgo State, Molango and Xochicoatlán, and is located in the Huasteca region in the Sierra Madre Oriental. Arboreal vegetation is divided in three vertical strata: high (20-30 m), medium (8-20 m) , and lower (2 -8 m). The flora of the area includes 391 species, 270 genera, and 112 families. Genera are grouped according to their present distribution in six categories; a high percentaje of them are exclusively American.

scholarly journals An Approach to the study of vessels climber species

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.

scholarly journals Magnolia guerrerensis (Magnoliaceae), una especie nueva del bosque mesófilo de montaña del estado de Guerrero, México

2017 ◽  
pp. 73
Author(s):  
Jaime Jiménez-Ramírez ◽  
Karla Vega-Flores ◽  
Ramiro Cruz-Durán ◽  
J. Antonio Vázquez-García
Keyword(s):  
New Species ◽  
Cloud Forest ◽  
The State ◽  
Especie Nueva ◽  
Bosque Mesófilo De Montaña ◽  
A New Species

Magnolia guerrerensis from the cloud forest in the state of Guerrero, Mexico, is illustrated and proposed as a new species. This taxon is similar to M. schiedeana Schltdl., but differs from it because of its smaller stipules, pedicellated flowers and gynoecium with less carpels. A key to distinguish both species is included.

scholarly journals The nature of the radius valley

2020 ◽  
Vol 643 ◽  
pp. L1 ◽  
Author(s):  
Julia Venturini ◽  
Octavio M. Guilera ◽  
Jonas Haldemann ◽  
María P. Ronco ◽  
Christoph Mordasini
Keyword(s):  
Mass Loss ◽  
Size Distribution ◽  
Point Of View ◽  
Parameter Study ◽  
Type I ◽  
Water Ice ◽  
Wide Range ◽  
Orbital Periods ◽  
Gas Accretion ◽  
Second Peak

The existence of a radius valley in the Kepler size distribution stands as one of the most important observational constraints to understand the origin and composition of exoplanets with radii between those of Earth and Neptune. In this work we provide insights into the existence of the radius valley, first from a pure formation point of view and then from a combined formation-evolution model. We run global planet formation simulations including the evolution of dust by coagulation, drift, and fragmentation, and the evolution of the gaseous disc by viscous accretion and photoevaporation. A planet grows from a moon-mass embryo by either silicate or icy pebble accretion, depending on its position with respect to the water ice line. We include gas accretion, type I–II migration, and photoevaporation driven mass-loss after formation. We perform an extensive parameter study evaluating a wide range of disc properties and initial locations of the embryo. We find that due to the change in dust properties at the water ice line, rocky cores form typically with ∼3 M⊕ and have a maximum mass of ∼5 M⊕, while icy cores peak at ∼10 M⊕, with masses lower than 5 M⊕ being scarce. When neglecting the gaseous envelope, the formed rocky and icy cores account naturally for the two peaks of the Kepler size distribution. The presence of massive envelopes yields planets more massive than ∼10 M⊕ with radii above 4 R⊕. While the first peak of the Kepler size distribution is undoubtedly populated by bare rocky cores, as shown extensively in the past, the second peak can host half-rock–half-water planets with thin or non-existent H-He atmospheres, as suggested by a few previous studies. Some additional mechanisms inhibiting gas accretion or promoting envelope mass-loss should operate at short orbital periods to explain the presence of ∼10–40 M⊕ planets falling in the second peak of the size distribution.

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