Silencing of retrovirus vectors poses a significant obstacle to genetic manipulation of stem cells and their use in gene therapy. We describe a mammalian silencer blocking assay using insulator elements positioned between retrovirus silencer elements and an LCRbeta-globin reporter transgene. In transgenic mice, we show that retrovirus silencers are blocked by the cHS4 insulator. Silencer blocki...

In the blocking paradigm, subjects receive reinforced presentations of a compound, AX, after reinforced presentations of A alone. Following this training, responding to X is often diminished relative to a control group, which did not receive the prior training with A. Standard associative theories of learning such as the Rescorla-Wagner model (Rescorla & Wagner, 1972) explain this effect by ass...

We have developed a multi-state mathematical model to describe the transmission of Plasmodium vivax malaria; the model accommodates variable transmission-blocking/enhancing immunity during the course of a blood infection, a short memory for boosting immunity, and relapses. Using the model, we simulated the incidence of human malaria, sporozoite rates in the vector population, and the level of t...

Although response blocking can decrease problem behavior, one potential adverse side effect is the induction of aggression. In the current study, we report on a young adult who engaged in high rates of pica maintained by automatic reinforcement. Blocking pica, however, led to aggression. When redirection to an alternative preferred food item was added to an intervention consisting of response b...

Previous studies have shown that paragigantocellularis nucleus (PGI) neurons contain some neurotransmitters such as GABA, neuropeptides, monoamines, substance P, enkephalin and serotonin. It has been suggested that PGI is a main cholinergic source in the rat’s brain stem. There are few evidences on the presence and importance of cholinergic receptors on PGI neurons with regard to nociception. I...

A novel GOD∼/AuNPs#rGO-CHIT/GC electrode was fabricated to realize the direct electron transfer of glucose oxidase (GOD) for rapid, highly sensitive and cost-effective determination BDE-15 based on blocking effect.

Optical packet/burst switching is considered a promising technique to improve the performance of optical networks. Key components in these technologies are the optical switching nodes. Some of these node architectures suffer from internal blocking. Synchronous operation allows overcoming most of the problems introduced by this internal blocking. However, in asynchronous networks internal blocki...

Many studies investigating cue competition have focused on the blocking effect. We investigated the blocking effect with pigeons using a landmark-based spatial search task in both a touchscreen preparation (Exp. 1a) and an automated remote environmental navigation apparatus (Exp. 1b). In Phase 1, two landmarks (LMs: A and Z) appeared on separate trials as colored circles among a row of eight (t...

We apply a causal inference-based framework to test and quantify previously suggested relationships between Northern Hemisphere blocking, upward wave-activity fluxes stratospheric polar vortex (SPV) variability using reanalysis data. show that the influence of blocking on is entirely mediated by fluxes, as classical view would suggest. However, pathway not completely straightforward. In contras...