Changes in anandamide levels in mouse uterus are associated with uterine receptivity for embryo implantation

Anandamide (N-arachidonoylethanolamine) is an endogenous ligand for both the brain-type (CB1-R) and spleen-type (CB2-R) cannabinoid receptors. This investigation demonstrates that the periimplantation mouse uterus contains the highest levels of anandamide (142-1345 pmol/micromol lipid P; 1-7 microg/g wet weight) yet discovered in a mammalian tissue. The levels fluctuate with the state of pregnancy; down-regulation of anandamide levels is associated with uterine receptivity, while up-regulation is correlated with uterine refractoriness to embryo implantation. Anandamide levels are highest during the nonreceptive phase in the pseudopregnant uterus and in the interimplantation sites, and lowest at the site of embryo implantation. The lower levels of uterine anandamide at the implantation sites may be a mechanism by which implanting embryos protect themselves from the detrimental effects of this endogenous ligand. We also observed a reduced rate of zona-hatching of blastocysts in vitro in the presence of anandamide, and inhibition of implantation by systemic administration of a synthetic cannabinoid agonist CP 55,940. These adverse effects were reversed by SR141716A, a specific CB1-R antagonist. Taken together, the results suggest that an aberrant synthesis of anandamide and/or expression of the cannabinoid receptors in the uterus/embryo may account for early pregnancy failure or female infertility.     

Simple linear profiles monitoring in the presence of within profile autocorrelation

Quality of some processes or products can be characterized effectively by a function referred to as profile. Many studies have been done by researchers on the monitoring of simple linear profiles when the observations within each profile are uncorrelated. However, due to spatial autocorrelation or time collapse, this assumption is violated and leads to poor performance of the proposed control charts. In this paper, we consider a simple linear profile and assume that there is a first order autoregressive model between observations in each profile. Here, we specifically focus on phase II monitoring of simple linear regression. The effect of autocorrelation within the profiles is investigated on the estimate of regression parameters as well as the performance of control charts when the autocorrelation is overlooked. In addition, as a remedial measure, transformation of Y-values is used to eliminate the effect of autocorrelation. Four methods are discussed to monitor simple linear profiles and their performances are evaluated using average run length criterion. Finally, a case study in agriculture field is investigated.     

Rayleigh waves in electrostrictive dielectric solids

Summary The possibility of the propagation of Rayleigh waves in an electrostrictive dielectric medium is investigated. It is shown that such waves can propagate, but they induce some body forces and surface tractions.     

Constitutive equations in Cosserat elasticity

Summary A new theory for the constitutive equations in Cosserat elasticity is proposed. It is based on the assumption that the rotation vector depending on the displacement vector should be coupled with a rotation vector independent of the displacement vector. This eliminates the indeterminancies in stress and couple-stress encountered earlier.     

Synthesis of polypyrrole/indium tin oxide nanocomposites via miniemulsion polymerization

Polypyrrole/indium tin oxide nanocomposites were synthesized via in situ miniemulsion polymerization of pyrrole monomer in the presence of indium tin oxide nanoparticles. Different nanocomposites were synthesized by different loadings of nano indium tin oxide. The morphology and nanoparticles distribution of the nanocomposites were characterized by electron microscopy. The results of XRD and TEM analysis showed that indium tin oxide nanoparticles were well placed in the polymeric structure of latex. FTIR analysis was used for the characterization of synthesized polypyrrole and its nanocomposites. TGA analysis was performed to investigate the thermal behavior of pristine polypyrrole and its nanocomposites. Conductivities of nanocomposites were measured by 4-point probe method and compared to the neat polymer.     

Polyvinyl butyral as a dispersant for barium titanate in a non-aqueous suspension

Polyvinyl butyral (PVB) was used as a dispersant for BaTiO₃ in a toluene-methanol system and its efficiency was evaluated by measuring the zeta potential and by a rheological study of the suspension. Addition of only 1.6 vol % low-molecular-weight (50 000) PVB is effective in making a well-dispersed suspension. But a lower concentration (0.6 vol %) of high-molecular-weight (200 000) PVB is necessary to stabilize the suspension due to the longer chain length of the polymer, which enhances steric stabilization. Dispersion of BaTiO₃ by PVB is better in a reverse azeotropic composition of toluene-methanol (72.427.6) than in an azeotropic composition.