Diagnostic study of the roughness surface effect of zirconium on the third-order nonlinear-optical properties of thin films based on zinc oxide nanomaterials

Zinc oxide (ZnO) and zirconium doped zinc oxide (ZnO:Zr) thin films were deposited by reactive chemical pulverization spray pyrolysis technique on heated glass substrates at 500 °C using zinc and zirconium chlorides as precursors. Effects of zirconium doping agent and surface roughness on the nonlinear optical properties were investigated in detail using atomic force microscopy (AFM) and third harmonic generation (THG) technique. The best value of nonlinear optical susceptibility χ(3) was obtained from the doped films with less roughness. A strong third order nonlinear optical susceptibility χ(3) = 20.12 × 10−12 (esu) of the studied films was found for the 3% doped sample

Influence of Roughness Surfaces on Third-Order Nonlinear-Optical Properties of Erbium-Doped Zinc Oxide Thin Films

ABSTRACT Zinc oxide (ZnO) and erbium-doped zinc oxide (ZnO:Er) thin films were deposited on heated glass substrates using the spray pyrolysis technique. Third-order nonlinear-optical properties of the thin films have been investigated using the third harmonic generation (THG) at wavelength of 1064 nm in picosecond regime. The dependence of third-order nonlinear susceptibility and transmission characteristics on the thin films roughness has been evaluated. Third-order nonlinear optical susceptibility (χ(3)) values of the studied materials were in the remarkable range of 10−2 esu. The morphologic properties of the deposited films have been analyzed using x-ray diffraction (XRD) and atomic force microscopy (AFM) and the luminescence properties by cathodoluminescence (CL). A correlation between optical properties and structural properties is given

Roughness effect on photoluminescence of cerium doped zinc oxide thin films

Undoped and cerium doped zinc oxide thin films have been prepared by spray pyrolysis technique. The influence of Ce as doping agent on the optical and nonlinear optical properties was carefully investigated using transmission, X-ray diffraction, photoluminescence, atomic force microscopy (AFM), and third harmonic generation (THG). It has been found a deep correlation between the surface roughness and the optical properties. In fact the roughness deteriorates the luminescence and nonlinear response, in a sense that the highest luminescence intensity and nonlinear susceptibility χ(3) are obtained for the smoothest layer.Doped layers are characterized with a high visible luminescence, attributed to cerium transitions, and susceptibilities in the range of 6.38 × 10−13 esu

Investigating the Willingness to Pay for a Contributory National Health Insurance Scheme in Saudi Arabia:A Cross-sectional Stated Preference Approach

Background: The Saudi Healthcare System is universal, financed entirely from government revenue principally derived from oil, and is ‘free at the point of delivery’ (non-contributory). However, this system is unlikely to be sustainable in the medium to long term. This study investigates the feasibility and acceptability of healthcare financing reform by examining households’ willingness to pay (WTP) for a contributory national health insurance scheme. Methods: Using the contingent valuation method, a pre-tested interviewer-administered questionnaire was used to collect data from 1187 heads of household in Jeddah province over a 5-month period. Multi-stage sampling was employed to select the study sample. Using a double-bounded dichotomous choice with the follow-up elicitation method, respondents were asked to state their WTP for a hypothetical contributory national health insurance scheme. Tobit regression analysis was used to examine the factors associated with WTP and assess the construct validity of elicited WTP. Results: Over two-thirds (69.6%) indicated that they were willing to participate in and pay for a contributory national health insurance scheme. The mean WTP was 50 Saudi Riyal (US$13.33) per household member per month. Tobit regression analysis showed that household size, satisfaction with the quality of public healthcare services, perceptions about financing healthcare, education and income were the main determinants of WTP. Conclusions: This study demonstrates a theoretically valid WTP for a contributory national health insurance scheme by Saudi people. The research shows that willingness to participate in and pay for a contributory national health insurance scheme depends on participant characteristics. Identifying and understanding the main influencing factors associated with WTP are important to help facilitate establishing and implementing the national health insurance scheme. The results could assist policy-makers to develop and set insurance premiums, thus providing an additional source of healthcare financing

Investigations of environmental radioactivity in the northern state of Sudan

Investigations have been carried out for naturally occurring radionuclides in surface soils in selected regions of the Northern State of Sudan, in response to widely spread rumours of elevated levels of radioactivity causing higher than normal incidence of cancer in that area. Eighty surface soil samples were collected from different regions in the Northern State and their activity concentrations were measured by a high-purity germanium detector gamma spectrometer system. From the data obtained the mean values and standard deviations of the radionuclide activities were calculated. From the activity concentrations of 226Ra, 232Th and 40K radionuclides the external absorbed dose rate in air and the annual effective dose were calculated. The radium equivalent activity and the external hazard index were applied for estimating the radiation hazards of soil used as building material. The mean activity concentrations of 226Ra, 232Th and 40K in different regions of the Northern State were found to be 82.6 + 6.8, 26.0 + 2.9 and 726.4 + 72.0 Bq/kg, respectively. The average outdoor gamma absorbed dose rate in air at 1meter above ground was calculated as 84.6 + 7.1 nGy/h. The average annual effective dose equivalent for population in the regions under study was found to be 103.7 + 8.7 uSv/y. The external hazard index was found to be 0.48 + 0.04

Being victims or beneficiaries? : perspectives on female genital cutting and reinfibulation in Sudan

Female Genital Mutilation (FGM) or the more value neutral term, Female Genital Cutting (FGC) is widely practised in northern Sudan, where around 90% of women undergo the most extensive form of FGC, infibulation. One new approach to combating FGC in Sudan is to acknowledge the previously hidden form of FGC, reinfibulation (RI) after delivery, when the woman is sewn back so much as to mimic virginity. Based on a qualitative study in Khartoum State, this article explores Sudanese women's and men's perceptions and experiences of FGC with emphasis on RI after delivery. The results showed that both genders blame each other for the continuation of the practices, and the comprehensive understanding of the perceptions and experiences was that both the women and the men in this study were victims of th e consequences of FGC and RI. The female narratives could be understood in the three categories: viewing oneself as being "normal" in having undergone FGC and RI; being caught between different perspectives; and having limited influence on the practices of FGC and RI. The male narratives could be understood in the three categories: suffering from the consequences of FGC and RI, trying to counterbalance the negative sexual effects of FGC and striving in vain to change female traditions. The results indicate that the complexity of the persistence of FGC and RI goes far beyond being explained by subconscious patriarchal and maternalistic actions, related to socially constructed concepts of normality, female identity,tradition and religion a"silent" culture betweenmen and women.La mutilation génitale féminine (MGF) ou bien le terme neutre de plus de valeur, l’excision génitale féminine (EGF) est pratiquée un peu partout au Soudan, où environ 90% des femmes subissent le type le plus coûteux de l’infibulation, l’EGF. Une nouvelle approche pour combattre l’EGF au Soudan consiste à reconnaître l’ancienne forme cachée de l’EGF, la reinfibulation après l’accouchement quand la femme est tellement recoussue si tellement comme pour imiter la virginité. Cet article qui est fondé sur une étude qualitative sur l’état de Khartoum explore les perceptions et l’expérience des femmes et des hommes soudanais par rapport à l’EGF, tout en mettant l’accent sur la RI après l’accouchement. Les résultats ont montré que les deux genres s’accusent l’un et l’autre pour la continuation de la pratique et la compréhension totale des perspectives et des expériences étaient que les femmes et les hommes dans cette étude sont victimes des conséquences des l’EGF et de la RI. Les narrations des femmes peuvent être comprises dans trois catégories: s’apercevant comme un être “normal” pour avoir subi l’EGF et la RI; être attrapées entre les perspectives différentes ayant une influence limitée sur les pratiques de l’EGF. Les narrations des hommes peuvent être comprises dans les trois catégories: la souffrance provoquée par les conséquences de l’EGF et la RI, les tentatives de contrebalancer les effets sexuels négatifs de l’EGF et s’efforcant en vain de changer les traditions féminines. Les résultats ont montré que la complexité de la persistence de l’EGF et la RI dépasse l’explication par la subconscient patriarchal et les actions matriarcales relatives aux concepts socialement construits par rapport à la normalité, l’identité, la tradition et la religion dans une culture “silencieuse” entre les hommes et les femmes

Do Micro Health Insurance Units Need Capital or Reinsurance? A Simulated Exercise to Examine Different Alternatives*

The purpose of this article is to provide a technical discussion of capital loading that “micro health insurance units” (MIUs) must add to the premium to maintain financial sustainability. MIUs offer benefit packages and require prepayment, that is, they create a rudimentary community-based health insurance for poor people in low-income countries. We broke up the 2001 data set of a health insurer containing upward of 1.3 million insureds into 535 “virtual MIUs”; and running 1,005 iterations, we got a data yield of 537,675 virtual MIUs. Capital loading levels increased steeply with decreasing group size and higher confidence levels. The impact of group size remains strong even with groups of 25,000 plus, and is stronger than the impact of changes in confidence levels. We discuss options to correct size-related premium bias through government subsidies, and conclude that reinsurance is cheaper than capital loading and a preferable solution for governments compared to other alternatives. The Geneva Papers (2006) 31, 739–761. doi:10.1057/palgrave.gpp.2510107