Bar-Ilan University

About: Bar-Ilan University is a education organization based out in Ramat Gan, Israel. It is known for research contribution in the topics: Population & Poison control. The organization has 12835 authors who have published 34964 publications receiving 995648 citations. The organization is also known as: Bar Ilan University & BIU.

The influence of film-induced mood on pain perception.

Abstract: It has been shown that a person's mood can influence pain tolerance Films have been used as a means of inducing a desired mood The effect on pain perception of film type and film length to induce mood was investigated Previous research with brief humorous films had not indicated any unique advantage of humor over distraction approaches Other recent research had indicated that after exposure to film stimulation there is a need to wait approximately 40 min before physiological changes can be obtained Thus, the present study varied both film type and length and introduced a 30-min waiting period following the mood induction via film prior to exposure to cold-pressor pain Two hundred subjects in nine different groups participated in the study Three types of films were used: (1) humorous, (2) holocaust, (3) neutral Three lengths of each type were also used: 15 min, 30 min, and 45 min In addition, a tenth no-film group served as a control for the effects of a film Each subject was given a baseline trial of cold-pressor pain, a trial immediately following the film and a trial 30 min later Results indicated an advantage in increased pain tolerance for the humorous film and an increased pain tolerance for the longer film regardless of type only after the 30-min waiting period Results were discussed from a pain theoretical perspective with emphasis placed on returning to psychological manipulations of the sensory aspects of pain and not just the cognitive/emotional/motivational dimensions

Epidemic threshold for the susceptible-infectious-susceptible model on random networks.

Abstract: We derive an analytical expression for the critical infection rate r{c} of the susceptible-infectious-susceptible (SIS) disease spreading model on random networks. To obtain r{c}, we first calculate the probability of reinfection π, defined as the probability of a node to reinfect the node that had earlier infected it. We then derive r{c} from π using percolation theory. We show that π is governed by two effects: (i) the requirement from an infecting node to recover prior to its reinfection, which depends on the SIS disease spreading parameters, and (ii) the competition between nodes that simultaneously try to reinfect the same ancestor, which depends on the network topology.

Role of actin cytoskeleton in mammalian sperm capacitation and the acrosome reaction

Abstract: In order to fertilize, the mammalian spermatozoa should reside in the female reproductive tract for several hours, during which they undergo a series of biochemical modifications collectively called capacitation. Only capacitated sperm can undergo the acrosome reaction after binding to the egg zona pellucida, a process which enables sperm to penetrate into the egg and fertilize it. Polymerization of globular (G)-actin to filamentous (F)-actin occurs during capacitation, depending on protein kinase A activation, protein tyrosine phosphorylation, and phospholipase D activation. F-actin formation is important for the translocation of phospholipase C from the cytosol to the sperm plasma membrane during capacitation. Prior to the occurrence of the acrosome reaction, the F-actin should undergo depolymerization, a necessary process which enables the outer acrosomal membrane and the overlying plasma membrane to come into close proximity and fuse. The binding of the capacitated sperm to the zona pellucida induces a fast increase in sperm intracellular calcium, activation of actin severing proteins which break down the actin fibers, and allows the acrosome reaction to take place.

Towards designing robust coupled networks

Abstract: Natural and technological interdependent systems have been shown to be highly vulnerable due to cascading failures and an abrupt collapse of global connectivity under initial failure Mitigating the risk by partial disconnection endangers their functionality Here we propose a systematic strategy of selecting a minimum number of autonomous nodes that guarantee a smooth transition in robustness Our method which is based on betweenness is tested on various examples including the famous 2003 electrical blackout of Italy We show that, with this strategy, the necessary number of autonomous nodes can be reduced by a factor of five compared to a random choice We also find that the transition to abrupt collapse follows tricritical scaling characterized by a set of exponents which is independent on the protection strategy