Search

Abstract Flexible organic light-emitting diodes (OLEDs) are promising light sources for biomedical applications. However, the use of these flexible devices has been restricted by their short shelf lifetimes due to poor ambient stability. Here, the fabrication of a long-lived flexible OLED is reported by replacing air-sensitive metals such as aluminum, and alkali metals used as n dopants, with silver. In addition, to achieve stable and efficient flexible OLEDs we tuned the optical cavity length to the second-order interference maximum. The device design has simple encapsulation and leads to an improvement in the air stability of flexible OLEDs which show a shelf lifetime of greater than 130 days whereas the conventional structure exhibits degradation after only 12 days. The proposed design for making flexible OLEDs demonstrates a great potential for using the devices for wearable bioelectronic applications.

Introduction: Breast cancer is the most commonly occurring cancer in women. It is also one of the most important health issues in many countries. Its high prevalence in women makes it necessary to encourage breast cancer screening behaviours. Aim: To investigate the relationship between breast cancer prevention behaviour and its screening behaviour in Tehranian women. Materials and Methods: This was cross-sectional study conducted on 859 women from November to December 2019 by the Iran University of Medical Sciences in Tehran, Iran. These women were selected by the multistage cluster method among five socio-economic classes living in different districts of Tehran. Structural Equation Modeling (SEM) was used to determine the relationship between breast cancer prevention behaviour and its screening behaviour. Data were analysed by Statistical Package for Social Sciences (SPSS) version 22.0 and Analysis of Moment Structures (AMOS) software. The level of significance was set at 0.05. Results: The mean age of the participants was 42±6.94 years. Also,137 (15.9%) of the participants were single, and 604 (70.3%) were married, 78 (9.08%) were divorced and rest widow. Among the studied subjects, 510 (57%) had unfavourable breast cancer screening behaviour. In Pearson’s correlation test, there was a direct and significant relationship between the mean score of breast cancer prevention behaviour and its subscales with breast cancer screening behaviour, except for the dimension of information-seeking (r=0.35, p=0.007). In other words, with the increased breast cancer prevention behaviour, breast cancer screening behaviour also increased. The results of SEM analysis showed that breast cancer prevention behaviour was positively correlated to breast cancer screening behaviour (p

Abstract Some applications of organic light‐emitting diodes (OLEDs) require large area, high light output, and high uniformity. It is difficult to achieve these attributes simultaneously because of voltage drops in the contacts, which cannot easily satisfy high optical transparency and electrical conductivity simultaneously. In large area OLEDs, thin electrodes with high sheet resistance induce voltage drops across the devices, leading to non‐uniform distribution of light. However, thick electrodes with low sheet resistance decrease the light output due to low transmittance. To overcome this trade‐off, a multilayer hybrid electrode based on Ag (20 nm)/WO3/Ag (20 nm)/WO3 is designed to obtain high electrical conductance with low optical loss. Compared to conventional devices using a single Ag (40 nm) top electrode, there is a considerable increase in the external quantum efficiency (EQE) of the device using this electrode (from 11.5% to 25.5% at 1000 cd m−2), while maintaining similar sheet resistance. In addition, a large area (≈57 cm2) OLED with the hybrid electrode demonstrates a luminance uniformity of 77% as compared to a device using single silver electrode with uniformity of 66%. Therefore, the proposed Ag/WO3/Ag/WO3 hybrid electrode is a promising choice for the fabrication of efficient and uniform large‐area OLEDs.

An ecologic study was conducted on 177 countries which the information of tobacco tax and price and also Human Development Index (HDI) was available in 2014. In this study, the relationship between HDI and four reported indexes by World Health Organization (WHO) was studied. These four indexes included: Tobacco affordability, Taxes as a percent of price of the most sold brand (total tax), Price of a 20 cigarette pack of the most sold brand international dollars at purchasing power parity (Price_ppp) and Price of a 20 cigarette pack of the most sold brand in US$ at official exchange rates (Price_US$). The data of HDI and tobacco were mined from WHO and United Nations Development Programme sites respectively. To study the correlation between HDI and the variables of this study, Pearson correlation coefficient was used and also Linear Regression Analysis was used to study the relationship between HDI and the variables of the study. According to the findings of the linear regression analysis, there was a significant relationship between HDI and total tax (B = 0.81, CI 95%: 0.63–0.99) and tobacco affordability (B = --0.35, CI 95%: --0.42 _ --0.28). There was also a significant relationship between HDI whit price-ppp (B = 9.44, CI 95%: 7.13–11.75) and price-US$ ;(B = 11.97, CI 95%: 9.71–14.23). According to the findings of this study, less developed countries devote less tax on tobacco. Due to the rising trend of the prevalence and also development of non-communicable diseases such as lung cancer in developing countries, policy makers of these countries are required to design stricter policies toward tobacco production and supply as well. Keywords: Tobacco, Tobacco affordability, Tobacco tax, Human Development Index

This study was conducted to investigate the effect of human development index (HDI) on tobacco smoking prevalence in men and women of countries which their data about tobacco smoking were available for 2015. Pearson's correlation coefficient and linear regression were used to investigate the association between HDI and all types of smoking, particularly cigarette. Daily smoking and current smoking were used as tobacco smoking indices. The information about prevalence of tobacco smoking and HDI was obtained from the World Health Organization (WHO) website and United Nations Development Programme (UNDP), respectively. The results showed that there is no statistically significant relationship between HDI and current tobacco smoking in men (B = −0.45_CI 95%: −29.97, 29.06). However, the same association was significant for women (B = 43.87, CI 95%: 24.97–62.78). The results indicated that women in developed countries are more at risk of health effects attributed to tobacco smoking. Countries should focus on socioeconomic factors to prevent the spread of risk factors for non-communicable diseases. Keywords: Tobacco, Cigarette smoking, Human development index

The present study investigated the effect of human development index (HDI) on diarrheal deaths per 1000 live births in children under 5 years old in 2015. In addition, the association between HDI, and the use of improved drinking-water sources and sanitation facilities were evaluated in this year. 75 countries that their information was available in Global Analysis and Assessment of Sanitation and Drinking-Water (GLAAS) conducted by the World Health Organization (WHO) were included in this study. The data required was obtained from WHO and United Nations Development Programme (UNDP) websites. Pearson's correlation coefficient and linear regression were used to evaluate the correlation and association between the variables, respectively. The results showed that there is a significant relationship between HDI and diarrhea-associated deaths per 1000 live births in children during 2015 (B = −354.85, CI95%: −408.91, −300.79). In addition, HDI was associated with the use of improved drinking-water sources (B = 83.93, CI95%: 64.71, 103.15) and improved sanitation facilities (B = 199.90, CI95%: 174.39, 225.42) in 2015. These findings indicate the association between HDI and the measures relevant to diarrheal disease among children. Therefore, in order to achieve to the Millennium Development Goals regarding child health, policymakers should concentrate on environmental and social factors affecting health. Keywords: Diarrhea, Drinking water, Sanitation, Human development index