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A silicon-based microchip for electrochromatographic separations is presented. Apart from a microfluidic network, the microchip has integrated UV-transparent waveguides for detection and integrated couplers for optical fibers on the chip, yielding the most complete chromatography microchip to date in terms of the integration of optical components. The microfluidic network and the optical component

This paper reports simultaneous detection of ultra violet (UV) absorbance and native UV-excited fluorescence in an electrophoresis microchip using UV transparent integrated waveguides. Absorbance detection enables detection of a wide range of analytes. When exposed to UV light, some compounds also exhibit native fluorescence, which is here detected simultaneously. Calibration curves were measured

Simultaneous label-free detection of UV absorbance and native UV-excited fluorescence in an electrophoresis microchip is presented. UV transparent integrated waveguides launch light at a wavelength of 254 nm from a mercury lamp along the length of a 1-mm long detection cell. Transmitted UV light is collected by another waveguide in the opposite end of the detection cell, while visible fluorescence

Cyclic olefin polymers (COPs) are increasingly popular as substrate material for microfluidics. This is due to their promising properties, such as high chemical resistance, low water absorption, good optical transparency in the near UV range and ease of fabrication. COPs are commercially available from a range of manufacturers under various brand names (Apel, Arton, Topas, Zeonex and Zeonor). Some

In this paper we present a method to characterize the acoustic trapping efficiency of nanoparticles and bacteria when using seeding particles. Through the use of fluorescent microscopy and video analysis, single particles/bacteria were counted as they entered the acoustic trap at different flow focusing ratios and by comparing the amount of trapped objects to the amount of objects that were lost f

We present a significantly improved acoustophoresis method to separate bacteria from red and white blood cells. As much as 98% of the bacteria were recovered, while only 0.06 % of the red and white blood cells remained. This 1600-fold relative enrichment was achieved by adjusting the center medium density, tightly controlling the chip temperature and stabilizing the fluid flows. This is a crucial

This paper presents an acoustofluidic chip for the sorting of bacteria from protozoa in water using standing acoustic waves. The size-based acoustophoretic sorting method provides a means for sample pre-concentration, which is vital for real-time, on-site monitoring of drinking water quality and preventing outbreak of waterborne diseases. In practice, high throughput and high recovery pre-concentr

Soil is likely the most complex ecosystem on earth. Despite the global importance and extraordinary diversity of soils, they have been notoriously challenging to study. We show how pioneering microfluidic techniques provide new ways of studying soil microbial ecology by allowing simulation and manipulation of chemical conditions and physical structures at the microscale in soil model habitats.The

Livestock manure is a valuable source of nutrients for crop production, but can also pose a public health hazard and have negative environmental impacts. This study investigated manure management practices among urban and peri-urban livestock keepers in Cambodia, to identify risk behaviours and socio-economic aspects associated with the handling of manure. A survey including 204 households was con

Resveratrol is a natural phenol with many positive effects for human health. However it is a photosensitive molecule with geometric isomerism, easily oxidised with short biological half-life and rapid metabolism and elimination. Thus, encapsulation of resveratrol is necessary. It has low solubility in water and in most of common oils. The goal of this work was to prepare oil-in-water emulsion stab

Water availability and water demand are not evenly distributed in time and space. Many mega water diversion projects have been launched to alleviate water shortages in China. This paper analyzes the temporal and spatial features of 59 mega water diversion projects in China using statistical analysis. The relationship between nine major basins is measured using a network analysis method, and the as

The term ‘private school’ as used in the Chinese context denotes a wide variety of schools, reaching from schools for poor rural children, to those for migrant children with external residency, to schools for children from the middle and upper classes seeking an education beyond the ordinary. Even though Chinese education has not undergone any large-scale privatization, an increasing number of fam

This chapter will look at the academic responses to China’s PISA performance as articulated in Chinese academic journals and educational newspapers. These responses belong largely to four different types: (i) Learning from PISA and its implications for assessing educational quality; (ii) establishing China as an educational role model; (iii) contrasting the Chinese system’s exam-efficiency with in

The structural properties, and the intracrystalline swelling of Na+-, and Ca2+-montmorillonite (Na-, and Ca-mmt) have been investigated as an effect of decreasing the relative permittivity of the solvent, i.e. from water to ethanol (EtOH), utilizing the experimental techniques; small angle X-ray scattering (SAXS) and osmotic pressure measurements. The experimental data were compared with the conti

This paper revisits stiffness optimization of non-linear elastic structures. Due to the non-linearity, several possible stiffness measures can be identified and in this work conventional compliance, i.e. secant stiffness designs are compared to tangent stiffness designs. The optimization problem is solved by the method of moving asymptotes and the sensitivities are calculated using the adjoint met

Coastal ecosystems are subjected to both large natural variability and increasing anthropogenic impact on environmental parameters such as changes in salinity, temperature, and pH. This study documents the distribution of living benthic foraminifera under the influence of multiple environmental stressors in the Skagerrak-Baltic Sea region. Sediment core tops were studied at five sites along a tran

Microgels are interesting as potential delivery systems for antimicrobial peptides. In order to elucidate membrane interactions of such systems, we here investigate effects of microgel charge density on antimicrobial peptide loading and release, as well as consequences of this for membrane interactions and antimicrobial effects, using ellipsometry, circular dichroism spectroscopy, nanoparticle tra