We consider nearly Kähler structures on a 6-dimensional sphere as sections of the twistor bundle over the sphere and prove that for any point of the space of twistor bundle there is a one-parameter ...family of nearly Kähler structures passing through the point. We study some properties of such one-parameter families.
The constitution of the ternary system CoaSiaTi was investigated using electron microscopy, energy dispersive spectroscopy, x-ray diffraction, and differential thermal analysis. Eleven ternary phases ...were identified and their homogeneity ranges characterized. The equilibria between these phases at 1000 degree C are presented in an isothermal section. A reaction scheme linking this isothermal section with the liquidus surface is derived. It contains three ternary eutectics at 1195 degree C, 1148 degree C and 988 degree C in the Si-rich, Co-rich and Ti-rich corners, respectively. The liquidus surface projection proposed shows large regions of primary crystallization for the congruently melting ternary phases I1-CoSiTi and I2-Co4Si7Ti4, the incongruently melting Laves phase (bundle) I6, as well as the binary phases CoSi, CoTi, and Ti5Si3.
We investigate monopoly profit under a new online tying strategy, namely sequential bundling. This method allows customers to buy additional products at discounted prices immediately after purchasing ...one or some of the available products. This strategy has been practiced by
Walmart
and others but has not been modelled to date. We use microeconomics analysis to conduct a comparison of the gained profit with the three commonly used bundling strategies: no bundling, pure bundling and mixed bundling. The main result shows that the sequential bundling strategy yields higher profits in comparison to all three classic strategies. In particular, for the symmetric cost case, our model provides a useful tool for practitioners such as common online shops.
This paper investigates the impact of product interrelatedness (substitutability and complementarity) on decision optimisation in a distribution channel consisting of a manufacturer and a retailer. ...The retailer purchases the manufacturer's product and retails it with another product as a bundle. The retailer decides the bundling strategy as a choice between full mixed bundling, partial mixed bundling, and pure bundling. Based on analytical models, we reveal how the degree of substitutability and complementarity influences the channel members' optimal bundling decisions. Considering substitutes, the retailer benefits from partial mixed bundling only when the substitutability is sufficiently high; otherwise, full mixed bundling dominates. The partial mixed bundling strategy outperforms full mixed bundling for the manufacturer when the substitutability is relatively high, but when it is not, full mixed bundling is better. Considering complements, the retailer will choose pure bundling as its optimal bundling strategy along with increasing complementarity. Otherwise, the retailer benefits from the partial mixed bundling with decreasing complementarity. The pure bundling strategy always improves the manufacturer's profit by expanding market demand significantly.
We establish a twistor correspondence between a cuspidal cubic curve in a complex projective plane, and a co-calibrated homogeneous G sub(2) structure on the seven-dimensional parameter space of such ...cubics. Imposing the Riemannian reality conditions leads to an explicit co-calibrated G sub(2) structure on SU(2, 1)/U(1). This is an example of an SO(3) structure in seven dimensions. Cuspidal cubics and their higher degree analogues with constant projective curvature are characterised as integral curves of certain seventh order ODEs. Projective orbits of such curves are shown to be analytic continuations of Aloff-Wallach manifolds, and it is shown that only cubics lift to a complete family of contact rational curves in a projectivised cotangent bundle to a projective plane.
How does fascin promote cancer metastasis? Lin, Shengchen; Taylor, Matthew D.; Singh, Pankaj K. ...
The FEBS journal,
March 2021, Letnik:
288, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Fascin is a pro‐metastasis actin‐bundling protein overexpressed in all carcinomas. This review will cover the biochemical basis for fascin‐bundling activity, the mechanisms by which cancer cells ...upregulate fascin expression and the mechanism underlying fascin‐mediated cancer cell migration, invasion, and metastatic colonization. We propose that fascin has broad roles in both metastatic dissemination and metastatic colonization. Understanding these mechanisms will be crucial to the development of anti‐metastasis therapeutics targeting fascin.
Fascin is an F‐actin‐bundling protein that cross‐links individual actin filaments into straight and stiff bundles. Fascin overexpression in cancer is strongly associated with poor prognosis and metastatic progression across different cancer types. It is well established that fascin plays a causative role in promoting metastatic progression. We will review the recent progress in our understanding of mechanisms underlying fascin‐mediated cancer metastasis. This review will cover the biochemical basis for fascin‐bundling activity, the mechanisms by which cancer cells upregulate fascin expression and the mechanism underlying fascin‐mediated cancer cell migration, invasion, and metastatic colonization. We propose that fascin has broad roles in both metastatic dissemination and metastatic colonization. Understanding these mechanisms will be crucial to the development of anti‐metastasis therapeutics targeting fascin.
Let S be a surface with pg(S)=0, q(S)=1 and endowed with a very ample line bundle OS(h) such that h1(S,OS(h))=0. We show that such an S supports families of dimension p of pairwise non-isomorphic, ...indecomposable, Ulrich bundles for arbitrary large p. Moreover, we show that S supports stable Ulrich bundles of rank 2 if the genus of the general element in |h| is at least 2.
A firm's two‐product bundling decision is examined when the supply of one product is limited and consumer valuations are normally distSteckeributed. The firm can choose to sell products separately ...and/or through a bundle. We find that the impact of limited supply on a firm's bundling decision depends on the correlation between the consumer valuations of the two products as well as the symmetry level of the two products in terms of their attractiveness (how much they are valued by consumers). When the valuation correlation is high and the symmetry level of the two products is low, limited supply can drive bundling. When the valuation correlation is low or the symmetry level is high, limited supply can drive no bundling. When the attractiveness of both products are low or the valuation correlation is very high, limited supply has no impact on a firm's bundling decision: The firm should not bundle for all supply levels.
This study offers a new driver for product bundling: the limited supply of a product. The existing bundling literature suggests that a firm should bundle symmetric products that have a low consumer valuation correlation, when bundling is driven by consumer valuation heterogeneity reduction. In contrast, when bundling is driven by limited supply, a firm should bundle asymmetric products with a high consumer valuation correlation. The benefit of supply‐driven bundling depends on the severity of supply limitation. When supply limitation is moderate, bundling creates value by expanding the market of the less attractive product. When supply limitation is severe, bundling enables a firm to extract a higher margin from the less attractive product.
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