Enumeration of torus-invariant strata with respect to dimension in the big cell of the quantum minuscule Grassmannian of type 𝐁_{𝐧}

2012 ◽  
pp. 27-40
Author(s):  
Jason Bell ◽  
Karel Casteels ◽  
Stéphane Launois
Keyword(s):  
Big Cell

scholarly journals Hopf algebras having a dense big cell

2015 ◽  
Vol 368 (1) ◽  
pp. 515-538 ◽  
Author(s):  
Julien Bichon ◽  
Simon Riche
Keyword(s):  
Hopf Algebras ◽  
Big Cell

scholarly journals Measurement of ploidy distribution in megakaryocyte colonies obtained from culture: with studies of the effects of thrombocytopenia

Blood ◽  
1981 ◽  
Vol 57 (2) ◽  
pp. 287-297 ◽  
Author(s):  
J Levin ◽  
FC Levin ◽  
DG Penington ◽  
D Metcalf
Keyword(s):  
Bone Marrow ◽  
Ploidy Level ◽  
Dna Content ◽  
Soft Agar ◽  
Distribution Characteristic ◽  
Cell Type ◽  
Big Cell ◽  
Platelet Depletion ◽  
Number Of Cells

Abstract Microdensitometric measurement of the DNA content of individual megakaryocytes was performed using megakaryocyte colonies obtained following culture, in soft agar, of hematopoietic cells from C57BL/6J mice. Two types of colonies were detected. After 7 days of culture, the big cell type contained 16 /+- 2.3 acetylcholinesterase (AChE) positive cells/colony, with a mean ploidy level of 16.8 /+- 0.8/cell and the ploidy distribution characteristic of recognizable megakaryocytes in bone marrow. The heterogeneous type contained 44 /+- 9.6 cells/colony (some of which were AChE negative), with a mean ploidy level of 6.8 /+- 0.7/cell. The ploidy distribution of heterogeneous colonies differed markedly from big cell colonies, with preponderance of 2N and 4N cells. Colony-forming cells, obtained 4–5 days after induction of acute thrombocytopenia, gave big cell colonies with a marked increase in DNA content. Mean ploidy level increased to 21.5 /%- 1.8/cell; the frequency of 32N cells increased from 17% to 30% and 64N cells from 0% to 6%. This is the pattern of change observed in bone marrow, in vivo, 24 to 48 hr after induction of acute thrombocytopenia. The number of cells/colony did not increase. In contrast, acute thrombocytopenia did not alter the ploidy of heterogeneous colonies. The different responses to the stimulus of acute thrombocytopenia suggest that there are at least two types of Meg-CFC. The delayed appearance of altered Meg-CFC that produced big cell colonies indicates that the pool of stem cells, from which committed megakaryocyte precursors are derived, may respond indirectly to the stimulus of platelet depletion.

Experimental investigation of low velocity impact on textile cellular composite with different energy construction

2018 ◽  
Vol 48 (6) ◽  
pp. 1009-1023 ◽  
Author(s):  
Xiaozhou Gong ◽  
Pengying Pei ◽  
Yu Hu ◽  
Xiaogang Chen
Keyword(s):  
Cell Size ◽  
Impact Energy ◽  
Initial Velocity ◽  
Low Velocity Impact ◽  
Wall Material ◽  
Low Velocity ◽  
Velocity Impact ◽  
Cellular Composite ◽  
Big Cell ◽  
The Impact

Cellular composite, with an array of regular hexagonal cells in the cross section, is a type of textile composites having the advantage of being light weight and energy absorbent over the solid composite materials. However, when it is under the same energy level of low velocity impact with different tup mass and velocity, its behavior is yet unknown. In the experiment, four groups of samples, with twelve geometrical variants have been systematically created for the impact testing. The impact test is running in two categories with one type of low velocity impact with initial velocity of 5.5 m/s by the tup mass of 0.55 kg, and another testing under the similar impact energy but with a lower initial velocity around 2.0 m/s with heavier tup mass of 4.52 kg. The impact energies in the above cases are very similar about 8.5 J, which indicates that the impact energy is the same while the energy construction is different. After the test, it is found that composite with medium cell size has more stable mechanical performances under various exposed impact conditions. It is also concluded that composites with big cell size are much easier to be destroyed under heavier impact tup, therefore, under condition of more critical loading force, it is necessary to find a way to enhance the big cell sized composites’ wall material in order to strengthen their structure performances. The results of this work provide a reference for the researchers who are kneeing to investigate the impact mechanism of textile cellular composites.

scholarly journals Measurement of ploidy distribution in megakaryocyte colonies obtained from culture: with studies of the effects of thrombocytopenia

Blood ◽  
1981 ◽  
Vol 57 (2) ◽  
pp. 287-297 ◽  
Author(s):  
J Levin ◽  
FC Levin ◽  
DG Penington ◽  
D Metcalf
Keyword(s):  
Bone Marrow ◽  
Ploidy Level ◽  
Dna Content ◽  
Soft Agar ◽  
Distribution Characteristic ◽  
Cell Type ◽  
Big Cell ◽  
Platelet Depletion ◽  
Number Of Cells

Microdensitometric measurement of the DNA content of individual megakaryocytes was performed using megakaryocyte colonies obtained following culture, in soft agar, of hematopoietic cells from C57BL/6J mice. Two types of colonies were detected. After 7 days of culture, the big cell type contained 16 /+- 2.3 acetylcholinesterase (AChE) positive cells/colony, with a mean ploidy level of 16.8 /+- 0.8/cell and the ploidy distribution characteristic of recognizable megakaryocytes in bone marrow. The heterogeneous type contained 44 /+- 9.6 cells/colony (some of which were AChE negative), with a mean ploidy level of 6.8 /+- 0.7/cell. The ploidy distribution of heterogeneous colonies differed markedly from big cell colonies, with preponderance of 2N and 4N cells. Colony-forming cells, obtained 4–5 days after induction of acute thrombocytopenia, gave big cell colonies with a marked increase in DNA content. Mean ploidy level increased to 21.5 /%- 1.8/cell; the frequency of 32N cells increased from 17% to 30% and 64N cells from 0% to 6%. This is the pattern of change observed in bone marrow, in vivo, 24 to 48 hr after induction of acute thrombocytopenia. The number of cells/colony did not increase. In contrast, acute thrombocytopenia did not alter the ploidy of heterogeneous colonies. The different responses to the stimulus of acute thrombocytopenia suggest that there are at least two types of Meg-CFC. The delayed appearance of altered Meg-CFC that produced big cell colonies indicates that the pool of stem cells, from which committed megakaryocyte precursors are derived, may respond indirectly to the stimulus of platelet depletion.

scholarly journals Morphology, anatomy and ultrastructure of yarrow (Achillea millefolium L.) floral nectaries

2012 ◽  
Vol 59 (1) ◽  
pp. 17-28 ◽  
Author(s):  
Aneta Sulborska ◽  
Elżbieta Weryszko-Chmielewska
Keyword(s):  
Cell Ultrastructure ◽  
Achillea Millefolium ◽  
Secretory Cells ◽  
Vascular Bundles ◽  
Cell Nuclei ◽  
Golgi Bodies ◽  
Glandular Cells ◽  
A Cell ◽  
Electron Microscopes ◽  
Big Cell

The studies focused on the morphological and anatomical features as well as those related to the ultrastructure of nectary cells <i>Achillea millefolium</i> Asteraceae family. The nectary presence was confirmed only in the disk flowers at the pistil style base. The micromorphology of nectaries was investigated in SEM, and structure was observed in a light and transmission electron microscopes. A number of layers composing a gland, the size and shape of epidermal and glandular cells were determined. The secretory cell ultrastructure was analyzed. The discoidal nectary gland observed from above had a pentagonal shape, 181.5 µm height and 299.4 µm diameter. It was built of the monolayer epidermis and 6 layers of the secretory cells on average. The glandular cells appeared to be bigger (27 µm) than the epidermal cells (22 µm), a cell shape in both tissues differed as well. The nectar secretion occured through the modified stomata. The stomata cells were at distinguishable greater size and raised above the surface of epidermis. The nectaries were supplied by the vascular bundles running from the pistil style up to the nectary base, not getting into the gland. In the cells of the nectary epidermis observed in TEM the big cell nuclei, numerous plastids, mitochondria and vacuoles with fibrous secretion deposits and vesicular structures were found. In the cells of the nectary secretory tissue there were dense cytoplasm, many plastids, mitochondria, Golgi bodies and the extensive network of the endoplasmic reticulum.

scholarly journals Ultrastructural analysis of murine megakaryocyte maturation in vitro: comparison of big-cell and heterogeneous megakaryocyte colonies

Blood ◽  
1987 ◽  
Vol 70 (5) ◽  
pp. 1509-1518
Author(s):  
PE Stenberg ◽  
J Levin
Keyword(s):  
Bone Marrow ◽  
Soft Agar ◽  
Small Cells ◽  
Specific Marker ◽  
Mouse Bone Marrow ◽  
Structural Level ◽  
Agar Culture ◽  
Big Cell ◽  
Mature Bone

Two morphologically distinct types of murine megakaryocyte (MK) colonies are present after three to seven days in soft agar culture: (a) “big-cell” colonies composed of ten to 30 large, mature-appearing megakaryocytes and (b) “heterogeneous” colonies consisting of approximately 100 or more cells at various stages of differentiation. Cytochemical and immunocytochemical techniques were used to study MK maturation in colonies as well as normal mouse bone marrow. Acetylcholinesterase (AChE), a specific marker for murine platelets and MK, was found in the perinuclear cisterna, endoplasmic reticulum, and occasionally, Golgi cisternae of MK in three-day big-cell colonies and immature bone marrow MK. MK in seven-day big-cell colonies and mature bone marrow MK showed additional reaction sites in the demarcation membrane system and occasional granules. In seven-day heterogeneous colonies, small cells resembled immature bone marrow MK with respect to AChE localization, whereas large cells corresponded to mature bone marrow MK. With immunogold procedures at the ultrastructural level, polyclonal antibodies against human platelet membrane glycoprotein IIIa and antimouse platelet antiserum labeled bone marrow MK and all MK from colonies grown in soft agar cultures for three to seven days. Granulocytes and macrophages in both bone marrow and soft agar cultures were negative for AChE and these immunocytochemical markers. These data indicate that the pattern of expression of AChE during maturation of MK is similar in vivo and in vitro and demonstrate, when using this marker at the fine-structural level, that a greater range of MK maturational stages is present in heterogeneous colonies than is observed in MK in big-cell colonies. Furthermore, we have confirmed that small cells in heterogeneous colonies are MK and that these colonies are composed solely of MK and their precursors.

The Lubrication Properties of Microbial Cells and their Biopolymers

2015 ◽  
Vol 794 ◽  
pp. 285-291
Author(s):  
Marvin Redetzky ◽  
Andreas Rabenstein ◽  
Benedikt Seidel ◽  
Ekkard Brinksmeier
Keyword(s):  
Extracellular Polymeric Substances ◽  
Microbial Cell ◽  
Metalworking Fluids ◽  
Premature Failure ◽  
Cell Counts ◽  
Water Based ◽  
Cell Components ◽  
Big Cell ◽  
High Level ◽  
Lubrication Properties

Many machining operations e.g. turning, milling or grinding are dependent on the application of water-based metalworking fluids (MWF) which contribute significantly to their high level of performance. MWF in-use are exposed to a microbial contamination, which leads to a deterioration of water-based MWF components and can cause a premature failure of the whole coolant system. Expensive monitoring and the addition of biocides are needed to maintain the MWF quality and to reduce the microbial load, regardless of the potential risk for health and environment. To overcome these limitations, the paradigm shift of using microorganisms as a replacement for conventional MWF is investigated in this paper. Microbial cell components and some microbial inclusions are comparable to conventional MWF components like e.g. fatty acids or sulfur compounds. Due to this fact, it is possible to create a regenerative system on a microbiological basis for the substitution of conventional MWF components. In preliminary tribological investigations the basic lubrication properties of microorganisms and their potential as a replacement for conventional MWF were shown. The presented approach intends to investigate the influence of microbial cell counts, cells size and extracellular polymeric substances (EPS) on the lubrication behavior respectively. The results of the tribological tests show that especially microorganisms with a big cell volume or a high EPS productivity exhibit superior Brugger-values (up to 174%) compared to a highly concentrated conventional MWF (emulsion 10%) and indicate the great potential of microorganisms as a replacement for conventional MWF.

scholarly journals Tempered D-modules and Borel–Moore homology vanishing

2021 ◽  
Author(s):  
Dario Beraldo
Keyword(s):  
Compact Support ◽  
De Rham Cohomology ◽  
Affine Grassmannian ◽  
D Modules ◽  
De Rham ◽  
Smooth Affine ◽  
Big Cell ◽  
Sigma G ◽  
Concrete Statement

AbstractWe characterize the tempered part of the automorphic Langlands category $$\mathfrak {D}({\text {Bun}}_G)$$ D ( Bun G ) using the geometry of the big cell in the affine Grassmannian. We deduce that, for G non-abelian, tempered D-modules have no de Rham cohomology with compact support. The latter fact boils down to a concrete statement, which we prove using the Ran space and some explicit t-structure estimates: for G non-abelian and $$\Sigma $$ Σ a smooth affine curve, the Borel–Moore homology of the indscheme $${\text {Maps}}(\Sigma ,G)$$ Maps ( Σ , G ) vanishes.

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