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Background Epoxy adhesives are one of the polymers used as high performance matrix in adhesives. However, the high brittleness and low toughness due to their high-crosslinking degree are critical problems during their service in structural applications. The lack of appropriate thermal stability at high temperature is another drawback of these valuable materials. In this study, the effect of hybrid reinforcement comprising zirconium oxide nanoparticles (NPs), phenolic resin (resol type) and poly (butyl acrylate-block-styrene) copolymer (BCP) on mechanical, adhesion, thermal and morphological properties of the epoxy adhesive was studied. Methods Mechanical properties, thermal stability, and microstructure of the epoxy adhesive was assessed using tensile test, TGA, and FESEM tests, respectively. To investigate the adhesion features, the formulated adhesive was applied in lap joint bonding of an aluminum to aluminum. Significant findings A new approach was developed for designing advanced adhesives with high mechanical, adhesion and thermal properties by adding hybrid additives. Based on the tensile test results, adding 5 phr of zirconium oxide nanoparticles to the epoxy adhesive increased the tensile strength, modulus, and the toughness of the dumbbell-shaped samples by 69%, 33% and 175% as compared with the neat epoxy adhesive, respectively. Furthermore, the highest improvement of shear strength in the single lap joint was observed in the sample containing 10 phr phenolic resin, 5 phr zirconia NPs, and 2.5 phr block copolymer, showing a 420% increment compared to the pure epoxy, reflecting the synergistic impact of these compounds at the mentioned percentage. The TGA results indicated the highest initial degradation temperature in the sample containing 5 phr zirconia NPs which was 54.4oC higher than that of the pure epoxy. The images of the fracture surface of the optimal samples in the tensile test showed that the cavitation, shear band formation, crack deviation, and crack tip blunting are among the major mechanisms in the increase of the toughness of the samples.

Beaulieu-Boycott-Innes syndrome (BBIS), an autosomal recessive disorder, is characterized by dysmorphic facial features and developmental delay. In this case study, we used the age and stages questionnaire 2 (ASQ-2) to assess the developmental status of an Iranian 20-month-old girl displaying a complex BBIS phenotype. Rehabilitation interventions were designed and performed focusing on neurodevelopmental delay. Because she had a severe developmental delay and her scores in all five domains of ASQ-2 were below the cut-off points available for Iranian children, the effectiveness of rehabilitation interventions was slower than expected. It seems that early rehabilitation and close follow-up should be considered for these children. We can assume that early and properly sensory-motor and cognitive interventions in these children may lead to growth development and prevent secondary complications.

Sarcocystosis caused by different Sarcocystis species and is a zoonotic protozoan infection with worldwide distribution in man and many animal species. In the present study, three techniques — direct inspection, impression smears and digestion method — were used for the diagnosis of Sarcocystis infection in 112 slaughtered sheep in a Kerman abattoir from November 2010 to May 2011. A total of 450 slaughtered sheep were selected randomly during three seasons, and their oesophagus and diaphragm were inspected using naked eye examination. In the second stage, 112 carcasses out of the 450 which had no apparent infection were selected randomly and their meat investigated using two techniques: impression smear with staining and pepsin digestion. The percentage of macroscopic cysts found in the oesophagus and diaphragm muscle was 6% and 2.88%, respectively, and microscopically, infection was found in 100% of the organs. There was no significant difference between different ages or between males and females. Although all of the sheep were found to be infected with Sarcocystis, majority of the cysts were demonstrated microscopically. This suggests that meat should be cooked sufficiently, since a macroscopic inspection may not provide true results.

In this paper, a new method for adaptive control of nonlinear systems using neural networks and Proportional-Integral-Derivative (PID) methodology is proposed. In this method, a PID control and adaptive linear neural network is used to control a inverted pendulum with uncertainities and external disturbances. The system consists of an inverted pole hinged on a cart which is free to move in the x direction. The performance of the proposed method is demonstrated via simulations.