Centralized Inverted Decoupling Control

This paper presents a new methodology of multivariable centralized control based on the structure of inverted decoupling. The method is presented for general n×n processes, obtaining very simple general expressions for the controller elements with a complexity independent of the system size. The possible configurations and realizability conditions are stated. Then, the specification of performance requirements is carried out from simple open loop transfer functions for three common cases. As a particular case, it is shown that the resulting controller elements have PI structure or filtered derivative action plus a time delay when the process elements are given by first order plus time delay systems. Comparisons with other works demonstrate the effectiveness of this methodology through the use of several simulation examples and an experimental lab process

Culture Method-Dependent Variation in the Sensitivity of Escherichia coli to Silver Nanoparticles

Preparation of various metal nanoparticles using plant extracts has been well studied in recent years. In this study, we found that nanoparticles synthesized using the extracts of the inflorescence of Cocos nucifera exhibited differential inhibitory activity against Escherichia coli depending on the nature of the bacterial culture source. Incorporation of silver nanoparticles (Ag-NPs) into the nutrient broth culture of E. coli resulted in poor inhibitory activity. However, when the silver nanoparticles are added to nutrient agar plates used for culture of E. coli, effective inhibition was observed. Additionally, E. coli in broth culture resisted the inhibitory effects of Ag-NPs by forming aggregates of bacterial cells. The aggregates then generated a protective zone around the colonies to prevent the entry of Ag-NPs, and the bacterial cells multiplied without inhibition by the Ag-NPs. These differential effects of Ag-NPs on E. coli culture grown in nutrient broth and on nutrient agar plates indicated that E. coli in broth culture formed aggregates of cells to develop a biofilm for protection against toxins probably via the quorum sensing mechanism

An Update on the Effectiveness of Probiotics in the Prevention and Treatment of Cancer

Probiotics are living microbes that play a significant role in protecting the host in various ways. Gut microbiota is one of the key players in maintaining homeostasis. Cancer is considered one of the most significant causes of death worldwide. Although cancer treatment has received much attention in recent years, the number of people suffering from neoplastic syndrome continues to increase. Despite notable improvements in the field of cancer therapy, tackling cancer has been challenging due to the multiple properties of cancer cells and their ability to evade the immune system. Probiotics alter the immunological and cellular responses by enhancing the epithelial barrier and stimulating the production of anti-inflammatory, antioxidant, and anticarcinogenic compounds, thereby reducing cancer burden and growth. The present review focuses on the various mechanisms underlying the role of probiotics in the prevention and treatment of cancer