This paper describes the development towards a miniaturized analytical system that can perform the major ke yf unctions of a flow cytometer. The development aims at diagnostic applications for cell counting and sorting with the ultimate goal of a low-cost portable instrument for point of care diagnosis. The present systems configuration consists of a disposable microfluidic device, that enables injection, single file cell flow through a miniaturized laser induced fluorescence detection system as well as sorting of identified samples. The microfluidic devices were fabricated by means of rapid prototyping technologies based on thick film photo-polymers. This paper reports various approaches on cell sorting and demonstrates sorting of single cells by means of an off-chip valve switching technique. The miniaturized fluorescence detection system employs active and passive micro-optical components, including semiconductor laser and ultra bright LED sources, highly sensitive avalanche photodiodes as well as micro-prism, holographic diffraction gratings and fibre optics for transmission and collection of light. Furthermore we demonstrate the feasibility of integrating solid-state components as part of an on-chip detection system. (Some figures in this article are in colour only in the electronic version)

Nanopore-based DNA analysis is a new single-molecule technique that involves monitoring the flow of ions through a narrow pore, and detecting changes in this flow as DNA molecules also pass through the pore. It has the potential to carry out a range of laboratory and medical DNA analyses, orders of magnitude faster than current methods. Initial experiments used a protein channel for its pre-defined, precise structure, but since then several approaches for the fabrication of solid-state pores have been developed. These aim to match the capabilities of biochannels, while also providing increased durability, control over pore geometry and compatibility with semiconductor and microfluidics fabrication techniques. This review summarizes each solid-state nanopore fabrication technique reported to date, and compares their advantages and disadvantages. Methods and applications for nanopore surface modification are also presented, followed by a discussion of approaches used to measure pore size, geometry and surface properties. The review concludes with an outlook on the future of solid-state nanopores.

With the global increase in the deployment of photovoltaic (PV) modules in recent years, the need to explore and understand their reported failure mechanisms has become crucial. Despite PV modules being considered reliable devices, failures and extreme degradations often occur. Some degradations and failures within the normal range may be minor and not cause significant harm. Others may initially be mild but can rapidly deteriorate, leading to catastrophic accidents, particularly in harsh environments. This paper conducts a state-of-the-art literature review to examine PV failures, their types, and their root causes based on the components of PV modules (from protective glass to junction box). It outlines the hazardous consequences arising from PV module failures and describes the potential damage they can bring to the PV system. The literature reveals that each component is susceptible to specific types of failure, with some components deteriorating on their own and others impacting additional PV components, leading to more severe failures. Finally, this review briefly summarises PV failure detection techniques, emphasising the significance of electrical characterisation techniques and underlining the importance of considering more electrical parameters. Most importantly, this review identifies the most prevalent degradation processes, laying the foundation for further investigation by the PV research community through modelling and experimental studies. This allows for early detection by comparing PV performance when failures or degradation occur to prevent serious progression. It is worth noting that most of the studies included in this review primarily focus on detailing failures and degradation observed in PV operations, which can be attributed to various factors, including the manufacturing process and other external influences. Hence, they provide explanations of these failure mechanisms and causes but do not extensively explore corrective actions or propose solutions based on either laboratory experiments or real-world experience. Although, within this field of study, there are corresponding studies that have designed experiments to suggest preventive measures and potential solutions, an in-depth review of those studies is beyond the scope of this paper. However, this paper, in turn, serves as a valuable resource for scholars by confining PV failures to critically evaluate available studies for preventative measures and corrective actions.