Disposable sensors in diagnostics, food and environmental monitoring

Disposable sensors are low‐cost and easy‐to‐use sensing devices intended for short‐term or rapid single‐point measurements. The growing demand for fast, accessible, and reliable information in a vastly connected world makes disposable sensors increasingly important. The areas of application for such devices are numerous, ranging from pharmaceutical, agricultural, environmental, forensic, and food sciences to wearables and clinical diagnostics, especially in resource‐limited settings. The capabilities of disposable sensors can extend beyond measuring traditional physical quantities (for example, temperature or pressure); they can provide critical chemical and biological information (chemo‐ and biosensors) that can be digitized and made available to users and centralized/decentralized facilities for data storage, remotely. These features could pave the way for new classes of low‐cost systems for health, food, and environmental monitoring that can democratize sensing across the globe. Here, a brief insight into the materials and basics of sensors (methods of transduction, molecular recognition, and amplification) is provided followed by a comprehensive and critical overview of the disposable sensors currently used for medical diagnostics, food, and environmental analysis. Finally, views on how the field of disposable sensing devices will continue its evolution are discussed, including the future trends, challenges, and opportunities

Factors that influence the expansion of the microenterprise sector: results from three national surveys in Zimbabwe

Using panel data from three nationwide surveys in Zimbabwe, an error components model is estimated to explore the factors that drive the small-enterprise sector. Among labour-intensive industries in urban areas, entry of new enterprises appears to be driven by surplus labour. This is supported by low barriers to entry and the negative relationship between economic growth and entry rates. In contrast, entry in capital-intensive industries is unrelated to economic growth and it is characterized by significant barriers to entry, including capital, working capital, and proprietor experience. With the exception of labour-intensive industries in rural areas, entry in all other small-enterprise industries is positively correlated with agricultural income. Copyright © 2003 John Wiley & Sons, Ltd.

Bike sharing: A review of evidence on impacts and processes of implementation and operation

© 2015 Elsevier Ltd. Despite the popularity of bike sharing, there is a lack of evidence on existing schemes and whether they achieved their objectives. This paper is concerned with identifying and critically interpreting the available evidence on bike sharing to date, on both impacts and processes of implementation and operation. The existing evidence suggests that bike sharing can increase cycling levels but needs complementary pro-cycling measures and wider support to sustainable urban mobility to thrive. Whilst predominantly enabling commuting, bike sharing allows users to undertake other key economic, social and leisure activities. Benefits include improved health, increased transport choice and convenience, reduced travel times and costs, and improved travel experience. These benefits are unequally distributed, since users are typically male, younger and in more advantaged socio-economic positions than average. There is no evidence that bike sharing significantly reduces traffic congestion, carbon emissions and pollution. From a process perspective, bike sharing can be delivered through multiple governance models. A key challenge to operation is network rebalancing, while facilitating factors include partnership working and inclusive scheme promotion. The paper suggests directions for future research and concludes that high-quality monitoring impact/process data, systematically and consistently collected, as well as innovative and inclusive evaluation methods are needed