BACKGROUND Chondrogenesis is the complex process that leads to the establishment of cartilage and bone formation. Due to their ability to differentiate in vitro and mimic development, embryonic stem cells (ESCs) show great potential for investigating developmental processes. In this study, we used chondrogenic differentiation of ESCs as a model to analyze morphogenetic events during chondrogene...

In this paper, we discuss the formation of collaboration networks among …rms that are located in a circular city. The model is a two-stage game. In the …rst stage, …rms form collaboration links, and in the second stage the …rms engage in price competition. The model in the second stage is a generalization of Salop’s (1979) model. We examine pairwise stability of networks and a stochastic networ...

Transmission of the malaria parasite from the mammalian host to the mosquito vector requires the formation of adequately adapted parasite forms and stage-specific organelles. Here we show that formation of the crystalloid-a unique and short-lived organelle of the Plasmodium ookinete and oocyst stage required for sporogony-is dependent on the precisely timed expression of the S-acyl-transferase ...

Malus hupehensis is an excellent Malus rootstock species, known for its strong adverse-resistance and apomixes. In the present study, stem cuttings of M. hupehensis were treated with three types of exogenous hormones, including indole acetic acid (IAA), naphthalene acetic acid (NAA), or green growth regulator (GGR). The effects and mechanisms of exogenous hormone treatment and antioxidant enzym...

study area is located in district of bajestan and ferdows cities, ne of iran. structurally, this area is part of lut block. the oldest exposed rocks, to the north of intrusive rocks and in eastern bajestan, are meta-chert, slate, quartzite, thin-bedded crystalline limestone and meta-argillite. the sedimentary units are: sardar formation (carboniferous), jamal formation (permian), sorkh shale an...

Aberrant gene silencing accompanied by DNA methylation is associated with neoplastic progression in many tumors that also show global loss of DNA methylation. Using conditional inactivation of de novo methyltransferase Dnmt3b in Apc(Min/+) mice, we demonstrate that the loss of Dnmt3b has no impact on microadenoma formation, which is considered the earliest stage of intestinal tumor formation. N...

We report on the energetics of intercalation of lithium, sodium and potassium in graphite by density functional theory using recently developed van der Waals (vdW) density functionals. First stage intercalation compounds are well described by conventional functionals like GGA, but van der Waals functionals are crucial for higher stage intercalation compounds and graphite, where van der Waals in...

microspore culture was applied to induce embryogenesis in roses (rosa hybrida) cv. hav1. important factors affecting viability of isolated microspores and formation of multi-cellular structures including isolation media (nln, ab, b) and induction media were studied. the most responsive developmental stage of microspores (late unicellular) was determined using dapi staining. the least infection ...

BACKGROUND Factor V (FV) in its activated form, FVa, is a critical regulator of thrombin generation during fibrin clot formation. There is a need of a simple, fast, and inexpensive microplate-based coagulation assay to measure the functional activity of FV in human plasma. The objective of this study was to develop a microplate-based assay that measures FV coagulation activity during clot forma...

amygdaloidal, cavity- and fracture-filling zeolites in eocene volcanic rocks from the kuh-e-aradeh of southern kahrizak, in the northernmost part of central iran have been studied in some detail by optical, chemical analysis, sem, and xrd techniques. the zeolites identified, in order of their relative time of formation from early to late, are tetranatrolite, analcime, natrolite, mesolite, stilb...