Immunization crisis may develop due to economic crisis during COVID-19 pandemic

COVID-19 pandemic is a global health crisis with 61, 149,391 confirmed cases and 370,478 deaths till 29May, 2020 [1]. This pandemic has shattered many economies with an estimated loss of $5.8 trillion to $8.8 trillion globally. This economic loss can result in reduction in funds to World Health Organization. Unfortunately, United States of America (USA) has announced termination of any further funding to WHO which can lead to another global health crisis[2]. As WHO is a voluntary funding based organization its main donor are America, China, Japan, Germany and United Kingdom. Among these USA is the main donor with a contribution of $115.8million alone followed by China $57.4 million, Japan $41million, Germany $29.1 million and UK $21.9 million [3].  America’s termination of funding can put WHO and child health programs in serious crisis. Among many programs run by WHO one of the most important program is immunization of children. Immunization coverage programs  save 2-3 million livesper year causing decline in measles related deaths, eradication of polio, surveillance of rotavirus, BCG and DTaP vaccination in children[4]. It is estimated that during MillenniumDevelopment Goal (MDG) there is overall decline in child related mortalities due to malaria, measles, diarrhea, AIDS and meningitis [5]. Remarkable results are achieved with measles are diarrhea immunization programs causing a decline in death rate by 73% and 80% respectively. According to a study with current success rate diarrhea related deaths can be virtually eliminated by 2030. Another successful program is “End Polio” program which eradicated polio from world except from Pakistan and Afghanistan [4][6]. This termination of funds to WHO can waste all previous efforts in developing countries. On the other hand despite of all efforts still 19.4 million children did not received prescribed dose of vaccines. Data analysis revealed among these  60% of children belong to 10 developing countries namelyAngola, Brazil, the Democratic Republic of the Congo, Ethiopia, India, Indonesia, Nigeria, Pakistan, the Philippines and Viet Nam [4]. These countries mainly rely on foreign funding and Non-Government Organization (NGOs) for child health care programs.

Investigation of Collective Modes and Instabilities in Quantum Plasmas

The investigation of electrostatic excitations and associated instabilities at the ionic timescale in ultra-high density (degenerate) quantum plasmas plays a fundamental role in understanding the collective interactions in superdense astrophysical systems, such as in white and brown dwarfs, in magnetars, in neutron stars as well as in laboratory such as in ultraintense laser-matter interaction experiments. In this context, a generalized relativistic Chandrasekhar equation of state (EoS) is employed for inertialess degenerate species (electrons/positrons), while the ions are taken as non-degenerate and inertial. The relativistic degeneracy effects in dense astrophysical plasmas play a vital role on the collective dynamics of degenerate dense plasmas. In this thesis, we primarily focus on the analytical and numerical study of linear and nonlinear ion-acoustic (IA) excitations in degenerate electron-positron-ion (e-p-i) dense plasmas, and in particular four different features are investigated. The first investigates the Korteweg-de Vries (KdV) and Korteweg-de Vries Burgers (KdVB) equations through the well-known reductive perturbation technique. Smaller (in amplitude) and narrower (in width) IA solitons are obtained for increasing values of relativistic degeneracy parameter and positron concentration, while taller and steeper shocks result for higher values of relativistic degeneracy parameter, positron content and ion kinematic viscosity. The second further extends the study to develop and investigate Zakharov-Kuznetsov (ZK) and Zakharov-Kuznetsov Burgers (ZKB) equations governing the three dimensional propagation of IA solitons and shocks in a magnetized degenerate e-p-i dense plasma. It is shown that the characteristics of IA solitons and shocks are substantially influenced by the intrinsic plasma parameters (i.e., the relativistic degeneracy parameter, the positron content, the ion gyrofrequency and the direction cosines). The third application is a comparative study of small amplitude and arbitrary amplitude IA waves in a degenerate e-p-i dense plasma with finite ion temperature effects. Concentrating on large amplitude IA excitations, the fluid equations are scaled and reduced to obtain an energy-balance equation in terms of the Sagdeev potential function. It is shown that the small amplitude expansion of the Sagdeev energy balance equation gives exactly the same result as predicted by the KdV theory, for pulses moving at a weakly supersonic velocity. The range of allowed values of the soliton speed (viz., the minimum and maximum Mach numbers), wherein solitary waves may exist, is determined. The impact of the key plasma configuration parameters, namely the electron relativistic degeneracy parameter, the ion temperature-to-electron Fermi temperature ratio and the positron content, on the soliton characteristics and existence domain, is examined numerically. The fourth involves a detailed theoretical and numerical analysis of nonlinear amplitude modulation of IA waves in a degenerate warm e-p-i plasma. By employing the multi- scale perturbative method, the nonlinear Schrödinger equation (NLSE) for the envelope amplitude is derived, based on which the modulational instability (MI) is also examined. In particular, the relativistic degeneracy parameter has the effect of attenuating the MI. It is shown that various types of localized IA excitations exist in the form of bright type solitons (envelope pulses) or dark type solitons (voids). The relativistic degeneracy parameter, the positron concentration and ion thermal effects significantly modify the occurrence conditions for MI, the associated threshold, the growth rate as well as the characteristics features (amplitude, width) of envelope solitary structures.