One of the most promising approaches to boost the communication efficiency in wireless systems is the use of multiuser diversity (MUDiv), where the fading of channels is exploited. The mechanism of scheduling the user with the best channel condition is called opportunistic scheduling (OS). In this paper we propose a joint polling and contention based feedback (JPCF) algorithm that exploits MUDi...

Action potentials (APs) are fundamental cellular electrical signals. The genesis of short APs lasting milliseconds is well understood. Ultra-long APs (ulAPs) lasting seconds to minutes also occur in eukaryotic organisms, but their biological functions and mechanisms of generation are largely unknown. Here, we identify TPC3, a previously uncharacterized member of the two-pore channel protein fam...

In future personal communications networks (PCN’s) supporting network-wide handoffs, new and handoff requests will compete for connection resources in both the mobile and backbone networks. Forced call terminations due to handoff call blocking are generally more objectionable than new call blocking. The previously proposed guard channel scheme for radio channel allocation in cellular networks r...

Ca(2) (+)-dependent protein kinases (CPKs) form a large family of 34 genes in Arabidopsis (Arabidopsis thaliana). Based on their dependence on Ca(2+), CPKs can be sorted into three types: strictly Ca(2+)-dependent CPKs, Ca(2+)-stimulated CPKs (with a significant basal activity in the absence of Ca(2+)), and essentially calcium-insensitive CPKs. Here, we report on the third type of CPK, CPK13, w...

For a number of mammalian ion channels, trafficking to the plasma membrane was found to be controlled by intrinsic sequence motifs. Among these sequences are diacidic motifs that function as endoplasmic reticulum (ER) export signals. So far it is unclear if similar motifs also exist in plant ion channels. In this study we analyzed the function of four diacidic DXE/DXD motifs of the plant K(+) c...

In this paper, a two-tier cellular wireless network is characterized by overlapping the service area for managing the new calls users having different mobility speed. The overlapping property of the two-tier system provides the advantages that share the traffic load to improve the efficiency of new calls subscriber with guard channels in cell to handle the handoff calls. Using Guard channels, o...

Aluminum (Al) inhibits inward K(+) channels (K(in)) in both root hair and guard cells, which accounts for at least part of the Al toxicity in plants. To understand the mechanism of Al-induced K(in) inhibition, we performed patch clamp analyses on K(in) in guard cells and on KAT1 channels expressed in Xenopus oocytes. Our results show that Al inhibits plant K(in) by blocking the channels at the ...

the iranian poultry sector has experienced many significant structural changes in recent years. such changes may have influenced price dynamics and transmission of shocks through marketing channels especially on retail markets. this paper investigate price transmission, threshold behavior and asymmetric adjustment in poultry sector of ardebil (ar), east azerbaijan (ea) and west azerbaijan (wa) ...