Stretched Exponential Relaxation in the Biased Random Voter Model

We study the relaxation properties of the voter model with i.i.d. random bias. We prove under mild condions that the disorder-averaged relaxation of this biased random voter model is faster than a stretched exponential with exponent $d/(d+\alpha)$, where $0<\alpha\le 2$ depends on the transition rates of the non-biased voter model. Under an additional assumption, we show that the above upper bound is optimal. The main ingredient of our proof is a result of Donsker and Varadhan (1979).Comment: 14 pages, AMS-LaTe

A QUALITATIVE ANALYSIS OF THE HIGH RACQUET POSITION BACKHAND DRIVE OF AN ELITE RACQUETBALL PLAYER

Since 1950, when Joe Sobek put strings on his paddleball paddle, the sport of racquetball has grown to the point where it has attained international status. Today, racquetball is played in 57 countries. It has been granted representation on the United States Olympic Committee (USOC) and is under consideration as a future Olympic sport, possible as early as the 1992 games. In spite of its rapid and international growth, racquetball remains a relatively new sport,on which very little research has been reported

RAPIDLY-LABELLED, ACIDIC PHOSPHOLIPIDS OF THE GOLDFISH BRAIN 1

Homogenates and particulate fractions of goldfish brain incorporated radioactivity from Γ-[ 32 P]ATP selectively into acidic phospholipids during brief periods of incubation. Phosphatidate and lysophosphatidate became strongly labelled and activity was also found in phosphatidyl inositol phosphate and in phosphatidyl inositol diphosphate. When tetraphenylborate (a K + -complexing agent) was added, a selective stimulation of incorporation of 32 P into phosphatidate occurred. The addition of perchlorate (also known to bind K + ) did not produce a similar stimulation, nor did the addition of K + block the stimulation by tetraphenylborate. The stimulation of the labelling of phospholipids by tetraphenylborate appeared to be the result of multiple actions. Besides the evidence that it acted by stimulating the phosphoinositide phosphodiesterase of brain, data were obtained suggesting that it stimulated diglyceride kinase and blocked endogenous destruction of ATP as well. The stimulation by tetraphenylborate was blocked by addition of atropine but not of arecoline.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65711/1/j.1471-4159.1970.tb03374.x.pd

A bulky glycocalyx fosters metastasis formation by promoting G1 cell cycle progression.

Metastasis depends upon cancer cell growth and survival within the metastatic niche. Tumors which remodel their glycocalyces, by overexpressing bulky glycoproteins like mucins, exhibit a higher predisposition to metastasize, but the role of mucins in oncogenesis remains poorly understood. Here we report that a bulky glycocalyx promotes the expansion of disseminated tumor cells in vivo by fostering integrin adhesion assembly to permit G1 cell cycle progression. We engineered tumor cells to display glycocalyces of various thicknesses by coating them with synthetic mucin-mimetic glycopolymers. Cells adorned with longer glycopolymers showed increased metastatic potential, enhanced cell cycle progression, and greater levels of integrin-FAK mechanosignaling and Akt signaling in a syngeneic mouse model of metastasis. These effects were mirrored by expression of the ectodomain of cancer-associated mucin MUC1. These findings functionally link mucinous proteins with tumor aggression, and offer a new view of the cancer glycocalyx as a major driver of disease progression

Large deviations for the one-dimensional Edwards model

Article / Letter to editorMathematisch Instituu