An opposed hydraulic free piston engine is under design at the Tianjin University in China because of the advantages of this engine compared to the conventional engine. The main challenges presented by such engines are the control of the piston motion and synchronization. This study investigates the fundamental control context and control method of the opposed hydraulic free piston engine using...

BACKGROUND The teenage population has a more favourable attitude towards organ donation than other population groups. Teenagers represent the future of the community and their opinion directly affects other family members and friends. Therefore, teenagers who are in favour of donation become promoters of organ donation in their area of influence. Our aim was to determine the opinion and fears o...

The effects of gravity on opposed-flow flame spread in a confined geometry were investigated experimentally in the 2.2-s drop tower at the NASA Glenn Research Center. Pure oxygen flowed through samples of 0.64-cminner-diameter polyvinyl chloride (PVC) tubing held either horizontally or vertically in a combustion chamber filled with nitrogen. The sample was ignited in normal gravity with a hot w...

Fluoridation has acquired the unenviable distinction of having become the most controversial issue in the history of dentistry. In one country after another throughout the world, wherever water supplies have been fluoridated or wherever fluoridation has even been considered, it has been vigorously opposed by increasing numbers of dentists, physicians, public health officials, biochemists, physi...

Influenza is a disease of global public health significance. Traditionally the emphasis has been on adult disease because of the impact of influenza related mortality in the elderly and other high risk groups. However, it is becoming increasingly better recognised that young children suffer considerable morbidity from influenza. There are also potential consequences for siblings, parents, other...

Sterilization levels reported in the Dominican Republic appear well above what we would normally expect given prevailing patterns in the region. We suspect that the use of strangers as interviewers--the normative approach in data collection in both developed and developing country settings--may be partly responsible for this result, and may underlie a long history of bias in family planning dat...

“Every Catholic Child in a Catholic School”: Historical Resistance to State Schooling, Contemporary Private Competition, and Student Achievement across Countries Nineteenth-Century Catholic doctrine strongly opposed state schooling. We show that countries with larger shares of Catholics in 1900 (but without a Catholic state religion) tend to have larger shares of privately operated schools even...

In a country in which contraception is controversial, abortion illegal and in which reproductive rights are limited, IVF is an unaffordable dream for most couples. But things are slowly changing in the only Christian democracy in Asia: the Philippines. In December 2012 the Senate passed the Reproductive Health bill and president Benigno Aquino III signed the measure into a law which is still no...