A Review of Chaos Control Strategies for Tri-trophic Food Chain Ecological Systems

The existence of chaos in ecological models is quite obvious due to the presence of nonlinear terms. Controlling chaotic phenomena in ecological systems remains a difficult task due to their unpredictability, and thus chaos control is one of the main objectives for constructing mathematical models in ecology today. Our aim in this paper is to review chaos control strategies for the tri-trophic food chain models by using various ecological factors. The factors include additional food, prey refuge, the Allee effect, the fear effect, and harvesting. We establish the essential conditions for the existence of ecologically feasible equilibrium points in the food chain ecological systems and their local stability. This paper provides a unified overview of recent research on the chaos control of ecological systems. The theoretical results suggest a way to control populations of species in ecological systems for fishing and pest management in farming. Numerical examples are performed to justify and compare the theoretical findings through phase portraits and bifurcation diagrams

Mutational Profile of Human Papilloma Virus (HPV) Induced and Non-HPV Induced Head and Neck Squamous Cell Carcinoma

Head and Neck cancer accounts for approximately 900,000 cases and over 400,000 deaths annually worldwide. The primary risk factors associated with Head and Neck cancer include usage of tobacco, alcohol consumption, Human Papillomavirus (HPV) infection and Epstein-Barr virus (EBV) infection. Few subsites of Head and Neck Squamous Cell Carcinoma (HNSCC) are associated with Human Papilloma Virus (HPV) while others remain non-associated. The anatomical, physiological, genetic, protein profile and epigenetic changes that occur in both HPV-positive and HPV-negative HNSCC has been discussed in this chapter. The mutational profile plays a crucial role in the treatment of the HNSCC patients as the HPV-positive HNSCC patients have a better prognosis compared to the HPV-negative HNSCC patients. This chapter mainly focusses on the mutational profile of both HPV-associated and non-HPV associated HNSCC tumours

Mitochondrial genetics and therapeutic overview of Leber's hereditary optic neuropathy

Leber's hereditary optic neuropathy (LHON) is a common inherited mitochondrial disorder that is characterized by the degeneration of the optic nerves, leading to vision loss. The major mutations in the mitochondrial genes ND1, ND4, and ND6 of LHON subjects are found to increase the oxidative stress experienced by the optic nerve cell, thereby leading to nerve cell damage. Accurate treatments are not available and drugs that are commercially available like Idebenone, EPI-743, and Bendavia with their antioxidant role help in reducing the oxidative stress experienced by the cell thereby preventing the progression of the disease. Genetic counseling plays an effective role in making the family members aware of the inheritance pattern of the disease. Gene therapy is an alternative for curing the disease but is still under study. This review focuses on the role of mitochondrial genes in causing LHON and therapeutics available for treating the disease. A systematic search has been adopted in various databases using the keywords “LHON,” “mitochondria,” “ND1,” “ND4,” “ND6,” and “therapy” and the following review on mitochondrial genetics and therapeutics of LHON has been developed with obtained articles from 1988 to 2017