A new class of magnetically actuated pumps and valves for microfluidic applications

This is the final version of the article. Available from Springer Nature via the DOI in this record.We propose a new class of magnetically actuated pumps and valves that could be incorporated into microfluidic chips with no further external connections. The idea is to repurpose ferromagnetic low Reynolds number swimmers as devices capable of generating fluid flow, by restricting the swimmers’ translational degrees of freedom. We experimentally investigate the flow structure generated by a pinned swimmer in different scenarios, such as unrestricted flow around it as well as flow generated in straight, cross-shaped, Y-shaped and circular channels. This demonstrates the feasibility of incorporating the device into a channel and its capability of acting as a pump, valve and flow splitter. Different regimes could be selected by tuning the frequency and amplitude of the external magnetic field driving the swimmer, or by changing the channel orientation with respect to the field. This versatility endows the device with varied functionality which, together with the robust remote control and reproducibility, makes it a promising candidate for several applications.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 665440. We also acknowledge support via the EPSRC Centre for Doctoral Training in Metamaterials (Grant No. EP/L015331/1)

Analysis of Complete Genome Sequence of <i>Acinetobacter</i> <i>baumannii</i> Strain ATCC 19606 Reveals Novel Mobile Genetic Elements and Novel Prophage.

Acinetobacter baumannii isolate ATCC 19606 was recovered in the US prior to 1948. It has been used as a reference and model organism in many studies involving antibiotic resistance and pathogenesis of A. baumannii, while, until recently, a complete genome of this strain was not available. Here, we present an analysis of the complete 3.91-Mbp genome sequence, generated via a combination of short-read sequencing (Illumina) and long-read sequencing (MinION), and show it contains two small cryptic plasmids and a novel complete prophage of size 41.2 kb. We also characterised several regions of the ATCC 19606 genome, leading to the identification of a novel cadmium/mercury transposon, which was named Tn6551. ATCC 19606 is an antibiotic-sensitive strain, but a comparative analysis of all publicly available ST52 strains predicts a resistance to modern antibiotics by the accumulation of antibiotic-resistance genes via plasmids in recent isolates that belong to this sequence type

Microfluidic devices powered by integrated elasto-magnetic pumps (article)

This is the final version. Available on open access from the Royal Society of Chemistry via the DOI in this recordThe dataset associated with this article is located in ORE at: https://doi.org/10.24378/exe.2863We show how an asymmetric elasto-magnetic system provides a novel integrated pumping solution for lab-on-a-chip and point of care devices. This monolithic pumping solution, inspired by Purcell's 3-link swimmer, is integrated within a simple microfluidic device, bypassing the requirement of external connections. We experimentally prove that this system can provide tuneable fluid flow with a flow rate of up to 600 μL h-1. This fluid flow is achieved by actuating the pump using a weak, uniform, uniaxial, oscillating magnetic field, with field amplitudes in the range of 3-6 mT. Crucially, the fluid flow can be reversed by adjusting the driving frequency. We experimentally prove that this device can successfully operate on fluids with a range of viscosities, where pumping at higher viscosity correlates with a decreasing optimal driving frequency. The fluid flow produced by this device is understood here by examining the non-reciprocal motion of the elasto-magnetic component. This device has the capability to replace external pumping systems with a simple, integrated, lab-on-a-chip component.Engineering and Physical Sciences Research Council (EPSRC)European Union Horizon 2020Medical Research Council (MRC)Royal SocietyWellcome Trus

Targeting Conservation Investments in Heterogeneous Landscapes: A distance function approach and application to watershed management

To achieve a given level of an environmental amenity at least cost, decision-makers must integrate information about spatially variable biophysical and economic conditions. Although the biophysical attributes that contribute to supplying an environmental amenity are often known, the way in which these attributes interact to produce the amenity is often unknown. Given the difficulty in converting multiple attributes into a unidimensional physical measure of an environmental amenity (e.g., habitat quality), analyses in the academic literature tend to use a single biophysical attribute as a proxy for the environmental amenity (e.g., species richness). A narrow focus on a single attribute, however, fails to consider the full range of biophysical attributes that are critical to the supply of an environmental amenity. Drawing on the production efficiency literature, we introduce an alternative conservation targeting approach that relies on distance functions to cost-efficiently allocate conservation funds across a spatially heterogeneous landscape. An approach based on distance functions has the advantage of not requiring a parametric specification of the amenity function (or cost function), but rather only requiring that the decision-maker identify important biophysical and economic attributes. We apply the distance-function approach empirically to an increasingly common, but little studied, conservation initiative: conservation contracting for water quality objectives. The contract portfolios derived from the distance-function application have many desirable properties, including intuitive appeal, robust performance across plausible parametric amenity measures, and the generation of ranking measures that can be easily used by field practitioners in complex decision-making environments that cannot be completely modeled. Working Paper # 2002-01

Epinephelus corallicola, Coral Grouper

Epinephelus corallicola is a fairly widespread, reef species that is naturally uncommon throughout its range. There are no directed fisheries, but it is occasionally caught and marketed. There is no evidence of population declines and no known major threats; therefore, it is listed as Least Concern. The change in status from the previous assessment reflects an improved application of the Red List categories and criteria, as well as a better understanding of available data

Epinephelus malabaricus, Malabar Grouper

This widely distributed species inhabits a variety of nearshore habitats. It can be common in parts of its range and is relatively fast-growing. Adults and juveniles are exploited by fisheries, especially for the live reef fish food trade based in Hong Kong. Population declines have occurred in the Andaman Islands, New Caledonia and the Philippines, and probably elsewhere in areas of heavy fishing pressure, but the level is not known or quantified. Even anecdotal information is missing from large areas of the range of this grouper, including Indonesia, most of East Africa, the Red Sea and New Guinea. Populations are considered to have remained healthy in Australia. Overfishing is a threat on a localised basis, and is not known to be driving global-level population declines that would approach a 'threatened' level. Therefore, it is listed as Least Concern. It is strongly recommended that fishery management and data collection is improved to monitor population trends, as well as additional research on its life history. The change in status from the previous assessment reflects an improved application of the Red List categories and criteria, as well as a better understanding of available data

Epinephelus malabaricus, Malabar Grouper

This widely distributed species inhabits a variety of nearshore habitats. It can be common in parts of its range and is relatively fast-growing. Adults and juveniles are exploited by fisheries, especially for the live reef fish food trade based in Hong Kong. Population declines have occurred in the Andaman Islands, New Caledonia and the Philippines, and probably elsewhere in areas of heavy fishing pressure, but the level is not known or quantified. Even anecdotal information is missing from large areas of the range of this grouper, including Indonesia, most of East Africa, the Red Sea and New Guinea. Populations are considered to have remained healthy in Australia. Overfishing is a threat on a localised basis, and is not known to be driving global-level population declines that would approach a 'threatened' level. Therefore, it is listed as Least Concern. It is strongly recommended that fishery management and data collection is improved to monitor population trends, as well as additional research on its life history. The change in status from the previous assessment reflects an improved application of the Red List categories and criteria, as well as a better understanding of available data

Aethaloperca rogaa, Redmouth Grouper

This widely distributed, Indo-West Pacific species inhabits reefs and is naturally uncommon. It is captured mostly incidentally in fisheries in many areas of its range, but this is not considered a major threat on a global level. It is listed as Least Concern. The change in status from the previous assessment reflects an improved application of the Red List categories and criteria, as well as a better understanding of available data

Plectropomus punctatus, Marbled Coral grouper

This widely distributed, reef-associated species is naturally uncommon in much of its range. It is a minor component of subsistence fisheries in parts of its range, but declines have not been detected. It is listed as Least Concern with a recommendation to improve monitoring of fished populations, especially in areas where pressure is expected to increase in the future, and to protect spawning aggregations. The change in status from the previous assessment reflects an improved application of the Red List categories and criteria, as well as a better understanding of available data