6,241 research outputs found
Effects of Ionospheric Asymmetry on Electron Density Standard Inversion Algorithm Applicable to Radio Occultation (RO) Data Using Best-suited Ionospheric Model
The "Onion-peeling" algorithm is a very common technique used to invert Radio Occultation (RO) data in the ionosphere. Because of the implicit assumption of spherical symmetry for the electron density (Ne) distribution in the ionosphere, the standard Onion-peeling algorithm could give erroneous concentration values in the retrieved electron density vertical profile Ne(h). In particular, this happens when strong horizontal ionospheric electron density gradients are present, like for example in the Equatorial Ionization Anomaly (EIA) region during high solar activity periods. Using simulated RO Total Electron Content (TEC) data computed by means of the best-suited ionospheric model and ideal RO geometries, we evaluated the asymmetry level index for quasi-horizontal TEC observations. This asymmetry index is based on the Ne variations that a signal may experience along its ray-path (satellite to satellite link) during a RO event. The index is strictly dependent on RO geometry and azimuth of the occultation plane and is able to provide us indication of the errors (in particular those concerning the peak electron density NmF2 and the vertical TEC) expected in the retrieval of Ne(h) using standard Onion-peeling algorithm. On the basis of the outcomes of our work, and using best-suited ionospheric model, we will try to investigate the possibility to predict the ionospheric asymmetry expected for the particular RO geometry considered. We could also try to evaluate, in advance, its impact on the inverted electron density profile, providing an indication of the product qualit
Investigating the Multiple Hit hypothesis of Parkinson disease using transgenic LRRK2-R1441G rats
The ‘multiple hit’ hypothesis of Parkinson disease (PD) suggests that the combination of several risk factors leads to the development of PD. Here, we explore the interaction between two potential causes of PD; a genetic mutation in the leucine-rich repeat kinase 2 (LRRK2) gene and exposure to the neurotoxin, Paraquat. This project characterizes transgenic BAC rats expressing human LRRK2 bearing the familial PD mutation, R1441G. These rats were tested for PD-related deficits at 3, 6, 9 & 12 months. These rats were then exposed to intraperitoneal injections of Paraquat. We hypothesized that LRRK2R1441G rats will show increased vulnerability to Paraquat compared to wildtype controls. Our results showed that LRRK2R1441G rats are not significantly different from wildtype rats by the 12 month stage, suggesting that this mutation alone is insufficient to manifest PD-like features in rats. In addition LRRK2R1441G rats failed to show increased vulnerability to Paraquat administration
Studies on some free living protozoan from Salim Ali lake. Aurangabad
Protozoa are one-celled animals found worldwide in most habitats. Most species are free living, but all higher animals are infected with one or more species of protozoa. Infections range from asymptomatic to life threatening, depending on the species and strain of the parasite and the resistance of the host. Present study deals with the free living protozoa inhabiting fresh water bodies. The factor which influence their distribution and population in a given water bodies temperature, light, pH, chemical composition, acidity, and amount of food present in water and degree of adaptability of the individual protozoa to various environmental changes. 
Social marketing of insecticide-treated bednets: The case for Pakistan
With an estimated half a million cases of malaria annually in Pakistan, and drug resistant cases on the increase, more practical preventive measures such as insecticide-treated bednets are essential. Social marketing through commercial channels has become an important cost-effective means to deliver health products and services to low income people and to motivate them to use these services. It has been demonstrated that social marketing of insecticide-treated bednets has saved the lives of millions of people in malaria-endemic regions at a cost as low as U.S. $2 per person. Social marketing could be an effective strategy for getting insecticide-treated nets to poor communities in Pakistan who are most vulnerable to malaria
Health seeking behaviour and health services utilization trends in national health survey of Pakistan: what needs to be done?
In developing countries, health seeking behaviours and health care services utilization patterns have been studied and the determinants have been classified in physical, socio-economic, cultural and political contexts. This paper is based on a systematic review of peer-reviewed literature on the relationship of factors affecting health service utilization and the focus has been on Pakistan. For this purpose, National Health Survey (NHS) of Pakistan, conducted in 1990-1994, has been critically reviewed. The review reveals specific behaviours following gender differences, socio-cultural milieu, disease patterns, household economics etc. Thus it becomes imperative to design evidence based policies by developing the understanding of health behaviours and health care utilization trends and to give enough credence to all determinants in the background. Health sector reforms therefore necessitate developing mechanisms to deliver more need based and quality services, considering thoughtfully users\u27 concerns and perspectives. The advent of decentralization in Pakistan provides a unique opportunity for tackling multi-faceted issues by multisectoral approaches
Stalling HIV through social marketing: prospects in Pakistan
Over the last two decades HIV/AIDS has evolved from a series of interesting case-reports to a growing epidemic that threatens the entire world. It is feared to cause devastation among large pockets of populations and may roll back more than thirty years of public health achievements. This killer disease has been more amenable to behavioral change than by provision of curative services and attempts are being made to educate the public about this threat. Various techniques of promotion have been tried through out the world including television dramas/soaps, mass media and school curricula. Social marketing is an evolving strategy used to influence human behavior and choices. By using the principles of marketing and promoting behavior as a product, social marketers attempt to understand the dynamics of human behaviour and devise messages and products to change, modify, accept or reject unsafe behaviors or practices. Thus, social marketers provide an effective force to combat the spread of HIV and may serve to be invaluable allies in health promotion efforts. In a complex and diversified cultural milieu of Pakistan, social marketing can have a significant impact on health determinants and the conditions that will facilitate the adoption of health-oriented behaviors and practices. This paper gives an account of the elements needed for the success of a health promotion strategy adopted in a developing country and makes a case for social marketing to be adopted as the lead strategy for stalling HIV/AIDS in Pakistan
Health seeking behaviour and health service utilization in Pakistan: challenging the policy makers
There is a growing literature on health seeking behaviours and the determinants of health services utilization especially in the context of developing countries. However, very few focused studies have been seen in Pakistan in this regard. This paper presents an extensive literature review of the situation in developing countries and relates the similar factors responsible for shaping up of a health seeking behaviour and health service utilization in Pakistan. The factors determining the health behaviours may be seen in various contexts: physical, socio-economic, cultural and political. Therefore, the utilization of a health care system, public or private, formal or non-formal, may depend on socio-demographic factors, social structures, level of education, cultural beliefs and practices, gender discrimination, status of women, economic and political systems environmental conditions, and the disease pattern and health care system itself. Policy makers need to understand the drivers of health seeking behaviour of the population in an increasingly pluralistic health care system. Also a more concerted effort is required for designing behavioural health promotion campaigns through inter-sectoral collaboration focusing more on disadvantaged segments of the population
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