Morphological and Anatomical Analysis of Vegetative Organs of Avena pilosa (Roem. & Schult.) Bieb.

The article provides information about the structural features of the fodder plant — Avena pilosa (Roem. & Schult.) Bieb., which is widespread on winter pastures in Azerbaijan. As a result of the morphological-anatomical analysis, important structural elements were identified, as well as the morphophysiology and adaptation of this species. As a result of adaptation to drought conditions, this plant showed signs of strong xerophilization. Xerophytes — plants for which the aridity of the norm. Common symptoms of xerophytes — a small evaporating surface, and other structural and physiological symptoms are very diverse. Reduction of leaf area is the main morphological feature of xerophytes

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Repression and Derepression of Minus-Strand Synthesis in a Plus-Strand RNA Virus Replicon

Journal of Virology ◽

10.1128/jvi.78.14.7619-7633.2004 ◽

2004 ◽

Vol 78 (14) ◽

pp. 7619-7633 ◽

Cited By ~ 51

Author(s):

Guohua Zhang ◽

Jiuchun Zhang ◽

Anne E. Simon

Keyword(s):

Solution Structure ◽

Rna Virus ◽

Structural Features ◽

General Mechanism ◽

Minus Strand ◽

Turnip Crinkle Virus ◽

Structural Elements ◽

Transcription In Vitro

ABSTRACT Plus-strand viral RNAs contain sequences and structural elements that allow cognate RNA-dependent RNA polymerases (RdRp) to correctly initiate and transcribe asymmetric levels of plus and minus strands during RNA replication. cis-acting sequences involved in minus-strand synthesis, including promoters, enhancers, and, recently, transcriptional repressors (J. Pogany, M. R. Fabian, K. A. White, and P. D. Nagy, EMBO J. 22:5602-5611, 2003), have been identified for many viruses. A second example of a transcriptional repressor has been discovered in satC, a replicon associated with turnip crinkle virus. satC hairpin 5 (H5), located proximal to the core hairpin promoter, contains a large symmetrical internal loop (LSL) with sequence complementary to 3′-terminal bases. Deletion of satC 3′-terminal bases or alteration of the putative interacting bases enhanced transcription in vitro, while compensatory exchanges between the LSL and 3′ end restored near-normal transcription. Solution structure analysis indicated that substantial alteration of the satC H5 region occurs when the three 3′-terminal cytidylates are deleted. These results indicate that H5 functions to suppress synthesis of minus strands by sequestering the 3′ terminus from the RdRp. Alteration of a second sequence strongly repressed transcription in vitro and accumulation in vivo, suggesting that this sequence may function as a derepressor to free the 3′ end from interaction with H5. Hairpins with similar sequence and/or structural features that contain sequence complementary to 3′-terminal bases, as well as sequences that could function as derepressors, are located in similar regions in other carmoviruses, suggesting a general mechanism for controlling minus-strand synthesis in the genus.

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Chondroitin sulfate and cytoplasmic domain-dependent membrane targeting of the NG2 proteoglycan promotes retraction fiber formation and cell polarization

Journal of Cell Science ◽

10.1242/jcs.114.12.2315 ◽

2001 ◽

Vol 114 (12) ◽

pp. 2315-2325 ◽

Cited By ~ 1

Author(s):

William B. Stallcup ◽

Kimberlee Dahlin-Huppe

Keyword(s):

Chondroitin Sulfate ◽

Rho Gtpase ◽

Cytoplasmic Domain ◽

Structural Features ◽

Cell Polarization ◽

Fiber Formation ◽

Structural Elements ◽

Motile Cells ◽

Chondroitin Sulfate Chain ◽

Ng2 Proteoglycan

Targeting of the NG2 proteoglycan to cellular retraction fibers was studied by expressing mutant NG2 molecules lacking specific structural elements of the proteoglycan. Both the cytoplasmic domain and the chondroitin sulfate chain of NG2 appear to have roles in sorting NG2 to subcellular microdomains destined to become retraction fibers. Neither of these structural features alone is sufficient to allow optimal targeting of NG2 to retraction fibers, but together they promote efficient localization of the proteoglycan to these sites. This pattern of NG2 sorting seems to be necessary for optimal retraction fiber formation, as cells expressing poorly targeted NG2 mutants are noticeably deficient in their ability to extend retraction fibers. Furthermore, retraction fiber formation correlates strongly with the tendency of cells to assume a polarized morphology with NG2-positive retraction fibers at one pole of the cell and actin-rich lamellipodia at the other. This polarization can be triggered either through engagement of NG2 by the substratum or by exposure to lysophosphatidic acid, a potent activator of the rho GTPase. These results suggest a possible role for NG2 in regulating rho-dependent mechanisms in the trailing processes of motile cells.

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Aspect structural du Medoc atlantique

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.s7-ii.6.796 ◽

1960 ◽

Vol S7-II (6) ◽

pp. 796-800

Author(s):

Michelle Caralp ◽

M. Vigneaux

Keyword(s):

Atlantic Coast ◽

River Mouth ◽

Structural Features ◽

Structural Elements

Abstract Data from some 10 boreholes in the area south of the Gironde river mouth on the Atlantic coast of France show that there are three main structural elements below the Quaternary cover. From north to south, these are the Hourtin syncline, the faulted Carcans anticline, and the block-faulted section south of Carcans. These structural features controlled Tertiary deposition and, in particular, explain the lateral facies variations of Miocene formations.

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A functional analysis of flying and walking in pterosaurs

Paleobiology ◽

10.1017/s009483730000765x ◽

1983 ◽

Vol 9 (3) ◽

pp. 218-239 ◽

Cited By ~ 114

Author(s):

Kevin Padian

Keyword(s):

Functional Analysis ◽

Shoulder Girdle ◽

Structural Features ◽

The Other ◽

Bipedal Locomotion ◽

Structural Elements ◽

Wing Membrane ◽

Other Hand ◽

Recovery Stroke

An analysis of the structure and kinematics of the forelimbs and hindlimbs of pterosaurs, and functional analogy with recent and fossil vertebrates, supports a reappraisal of the locomotory abilities of pterosaurs. A hypothesis of structural, aerodynamic, and evolutionary differences distinguishing vertebrate gliders from fliers is proposed; pterosaurs fit all the criteria of fliers but none pertaining to gliders. The kinematics of the reconstructed pterosaur flight stroke reveal a down-and-forward component found also in birds and bats; structural features of the shoulder girdle and sternum unique to pterosaurs may be explained in light of this motion. The recovery stroke of flight was accomplished, in birdlike fashion, by a functional reversal of the action of theM. supracoracoideusby the pronounced enlargement of the acrocoracoid process, which acted as a pulley. The wing membrane was supported and controlled through a system of stiffened, intercalated fibers, which were oriented like the main structural elements in the wings of birds and bats.The hindlimbs of pterosaurs were independent of the wing membrane, and articulated like those of other advanced archosaurs and birds, not like those of bats. The gait was parasagittal and the stance digitigrade. Because of limitations on the motion of the forelimb at the shoulder, pterosaurs could not have walked quadrupedally. However, bipedal locomotion appears to have been normal and quite sufficient in all pterosaurs. There is nothing batlike about pterosaur anatomy; on the other hand, pterosaurs bear close structural resemblances to birds and dinosaurs, to which they are most closely related phylogenetically.

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Radiation and water balance properties of cadmium-polluted maize in a wet year

Acta Agronomica Hungarica ◽

10.1556/aagr.60.2012.3.2 ◽

2012 ◽

Vol 60 (3) ◽

pp. 191-200 ◽

Cited By ~ 1

Author(s):

A. Anda

Keyword(s):

Leaf Area ◽

Dry Matter ◽

Sensible Heat ◽

Net Radiation ◽

Yield Losses ◽

Vegetative Organs ◽

Unit Leaf ◽

Silage Maize ◽

Matter Production ◽

Annual Water

The effect of spraying maize weekly with a 0.5 M concentration of Cd was studied in Hungary at two water supply levels. Cd reduced the size of the leaf area and the annual water loss. The intensity of evapotranspiration (mm water/unit leaf area) of the polluted crops grew. The higher net radiation of polluted maize resulted in an increase in sensible heat and a warmer canopy. The warmer the canopy, the higher the stress level of the contaminated crops was. While Cd caused a 28% significant decline in plant dry matter production in the rainfed plots, only a declining tendency amounting to a few percent was recorded in the ET treatment.Cd of atmospheric origin was only detected in the leaves; it was not accumulated in the grain. It was concluded from the results that the yield losses in grain maize grown on Cd-polluted areas could be mitigated by irrigation. The production of silage maize, however, is not recommended in regions affected by Cd pollution, especially in areas where irrigation is required, since supplementary water supplies promote the accumulation of Cd in the vegetative organs.

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Anatomy of vegetative organs with an emphasis on the secretory structures of two species of Aldama (Asteraceae–Heliantheae)

Botany ◽

10.1139/cjb-2012-0271 ◽

2013 ◽

Vol 91 (6) ◽

pp. 335-342 ◽

Cited By ~ 19

Author(s):

Tuane Oliveira ◽

Aline Bertolosi Bombo ◽

Beatriz Appezzato-Da-Glória

Keyword(s):

Adventitious Roots ◽

Glandular Trichomes ◽

Diagnostic Value ◽

Aromatic Plants ◽

Secretory Structures ◽

Vegetative Organs ◽

Anatomical Features ◽

Anatomical Analysis ◽

Secretory Cavities ◽

Underground System

Aldama arenaria (Baker) E.E.Schill. & Panero and Aldama robusta (Gardner) E.E.Schill. & Panero are aromatic plants, morphologically very similar and usually confused on the analysis of exsiccates. The present study aimed to identify the secretory structures present in vegetative organs and to survey for anatomical features with diagnostic value between A. arenaria and A. robusta based on an examination of these organs. Aldama arenaria and A. robusta exhibit hydathodes in the dentate ornamentations of the leaf margins and apices in addition to glandular trichomes, secretory cavities and ducts, all of which vary with respect to type and location in each species. Xylopodia and adventitious roots constitute the underground system. The xylopodium is covered by epidermis or by suberised cells resulting from periclinal divisions of parenchyma cells. The tuberisation process of adventitious roots results mainly from hypertrophy and hyperplasia of medullary cells, especially in A. arenaria. Through anatomical analysis, useful features for distinction between A. arenaria and A. robusta in exsiccates and fresh materials were identified, and these features were related mainly to the position and frequency of secretory structures.

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Structural Analysis in Transit System Using Network Theory Case of Guadalajara, Mexico

Urban Science ◽

10.3390/urbansci5040087 ◽

2021 ◽

Vol 5 (4) ◽

pp. 87

Author(s):

Orlando Barraza ◽

Miquel Estrada

Keyword(s):

Structural Analysis ◽

Network Theory ◽

Planning Process ◽

Structural Features ◽

Transport Network ◽

Structural Elements ◽

Transit System ◽

Transit Network ◽

Network Properties ◽

In Transit

Structural analysis in a transit network is a key aspect used to evaluate in a planning process. In this sense, the use of network science was applied in this work to generate a framework of the main structural features of a transport network. In this case, an alternative transport network in Guadalajara, Mexico was taken as an example. The network properties selected were grade of accessibility, spatial friction, and vulnerability. In the case of the grade of accessibility, this propriety makes reference to the efficiency of the travel time that the network gives due to its structural features. The spatial friction measures how direct in terms of distance the trips that the network provides are, and the vulnerability relates to the ease with which the network can comprise its performance by affectations to their nodes or links. In this sense, this work presents a detailed methodology and a set of open-source tools that can be used to measure these key structural elements for decision making.

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Structural elements influencing von Willebrand factor (vWF) binding affinity for platelet glycoprotein Ib within a dispase-digested vWF fragment

Blood ◽

10.1182/blood.v84.5.1553.bloodjournal8451553 ◽

1994 ◽

Vol 84 (5) ◽

pp. 1553-1558 ◽

Cited By ~ 1

Author(s):

S Miura ◽

Y Fujimura ◽

M Sugimoto ◽

T Kawasaki ◽

Y Ikeda ◽

...

Keyword(s):

Binding Affinity ◽

Von Willebrand Factor ◽

Disulfide Bridge ◽

Structural Features ◽

Platelet Glycoprotein ◽

Structural Elements ◽

Competitive Binding Assay ◽

Sugar Chains ◽

Von Willebrand ◽

Willebrand Factor

We investigated the structural elements in human von Willebrand factor (vWF) that influence binding affinity for platelet glycoprotein (GP) Ib using a dispase-digested vWF fragment as a prototype (residues Leu480/Val481-Gly718 of the vWF subunit; Andrews et al, Biochemistry 28:8326, 1989). The major structural features of this fragment are a large A1-loop formed by an intrachain disulfide bond between Cys509 and Cys695 and six O-linked sugar chains. The fragment was chemically modified by (1) reduction and S-carboxyamido-methylation (R/A), (2) desialylation (DS), or (3) a combination of both (R/A-DS). The GPIb binding affinity of these fragments was basically evaluated by competitive binding assay with anti-GPIb monoclonal antibody (LJ-Ib1), a receptor blocker for vWF (Sugimoto et al, Biochemistry 30:5202, 1991). Both the prototype and the R/A fragments were also assessed for their function in shear-induced platelet aggregation. Results unambiguously demonstrated that the presence of a disulfide bridge (Cys509-Cys695) within this domain downregulates the affinity of vWF to GPIb. In addition, it was also demonstrated that the terminal sialic acids attached to six o-linked sugar chains within this domain contribute to optimal functional modulation by the antibiotic ristocetin, but not by snake venom botrocetin.

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