This paper deals with containment control of multi‐agent systems where high‐order canonical controllable linear systems with heterogeneous uncertainties are considered as the agents' dynamics. The leaders are dynamic with polynomial‐type trajectories. In this paper, the control protocol is smooth and it is constructed from a flexible combination of local state feedback controller and a PI‐type protocol. Utilizing this protocol, containment without suffering from chattering phenomena and consideration of any bound on the agents' states is achieved. In addition, the flexibility of this protocol helps the designer to reduce or even discard the inter‐agent communication. Recalling the significant effects of time delay on the performance and stability of multi‐agent systems, in this paper input time delay is also considered. Following a Lyapunov‐Krasovskii stability approach, two linear matrix inequalities (LMIs) are derived, and then solving the LMIs' gains of the protocol are attained such that asymptotic stability of the multi‐agent system under switching graph topology is guaranteed. Finally, the feasibility of the LMIs and the validity of the theoretical results are demonstrated through some numerical examples.

This paper employs nonlinear disturbance observer for robust Nonlinear Model Predictive Control (NMPC) of biped robots. The NMPC is used in order to imitate some properties of human walking, which is optimal and uses some basic goals and constraints, yielding safe and stable walking. Since there may be some uncertainties in the dynamics or parameters variations in the biped model, the controller robustness is also considered. However, the NMPC is a model based controller; this characteristic reduces the effectiveness of the NMPC based controlling. In order to overcome this shortcoming of the NMPC, the nonlinear disturbance observer (NDO) will be used to robustify the proposed controller against dynamic uncertainties in the biped robot and rejecting external disturbances. Simulation results reveal better performance of the nonlineardisturbance-observer-based NMPC as compared to the previously reported NMPC controllers.

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Background: Breast cancer is the most common malignancy in females worldwide. Several etiological factors including environmental factors have been recognized for breast cancer. Epstein Barr virus as a viral etiological factor has been proposed. So far, several studies have investigated the relationship between development of breast cancer and Epstein Barr virus, but few have been done in Iran. The aim of this study was to determine whether there was an association between EBV infection and female breast cancer in Iran. Materials and Methods:We analyzed paraffin embedded breast tissue specimens by polymerase chain reaction (PCR) including breast cancer specimens (as case group) and breast fibroadenoma specimens (as control group). PCR was performed to amplify specific sequences of EBV. Results: From 130 cases of breast samples, 67 cases of breast cancer tissues and 41 cases of breast fibroadenoma tissues had adequate quality and quantity of DNA to detect EBV. PCR for EBV was positive in 4 invasive ductal carcinoma specimens (7.3%) and only one of the fibroadenoma specimens (2.4%). No significant association was found between EBV infection and invasive ductal carcinoma (p> 0.05). Also, patient's age and histological grade of IDC were not correlated with EBV infection (p>0.05). Conclusion:We observed no etiologic association between EBV infection and invasive ductal carcinoma of female breast in our regions; however, further studies are required to elucidate this association.

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