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The BioMedical Admissions Test (BMAT) has been used to select students for healthcare courses for 15 years. Recently, the candidature has included an increasing number of test takers who did not complete their schooling in the UK. In line with responsibilities to promote widening participation, a revision of the Section 2 Scientific Knowledge and Applications specification was conducted, to support the preparation of candidates from under-represented groups and international candidates. The process was guided by validity frameworks established in language testing research, with a particular focus on consequential validity and washback. Candidate surveys are reported to illustrate the focus on test preparation. Issues identified in the review demonstrate the impact of international test-takers' linguistic backgrounds and differences in teaching approaches, and possible interactions between these are discussed. It is recommended that admissions test developers make use of holistic frameworks of validity from other contexts to systematically interrogate a wide range of validity evidence relating to their tests.

Significant advances are being made in the incorporation of enzymes into functional materials, which leverage their inherent substrate specificity, efficient catalytic activity, and sustainable origin. These engineered "dead" materials, however, lack the incredible systems‐level control of enzyme activity that living organisms have evolved over millennia. This gap is now being bridged by the rapidly emerging field of engineered living materials (ELMs), which couples the tools of advanced synthetic biology with modern materials science. In this review, the impressive array of methodologies used to fabricate the extensive library of functional enzyme‐based dead materials is discussed, and the design strategies that facilitate their creation unpacked. The spectacular suite of natural and synthetic genetic and post‐translational control systems for enzymes in living organisms is then described. Finally, key recent examples of ELMs that utilize enzyme activity are reviewed, highlighting the central role of the living component in providing responsivity and adaptability to this new class of materials. [ABSTRACT FROM AUTHOR]

Respiratory syncytial virus (RSV) causes severe infections in infants, immunocompromised or elderly individuals resulting in annual epidemics of respiratory disease. Currently, limited clinical surveillance and the lack of predictable seasonal dynamics limit the public health response. Wastewater-based epidemiology (WBE) has recently been used globally as a key metric in determining prevalence of severe acute respiratory syndrome coronavirus 2 in the community, but its application to other respiratory viruses is limited. In this study, we present an integrated genomic WBE approach, applying reverse-transcription quantitative polymerase chain reaction and partial G-gene sequencing to track RSV levels and variants in the community. We report increasing detection of RSV in wastewater concomitant with increasing numbers of positive clinical cases. Analysis of wastewater-derived RSV sequences permitted identification of distinct circulating lineages within and between seasons. Altogether, our genomic WBE platform has the potential to complement ongoing global surveillance and aid the management of RSV by informing the timely deployment of pharmaceutical and nonpharmaceutical interventions. [ABSTRACT FROM AUTHOR]

The synthesis of a porous shape‐changing interpenetrating network (IPN) bioink for the fabrication of large‐scale (cm) reversibly thermosensitive structures is described. The poly(N‐isopropylacrylamide) (PNIPAm) IPN is generated in situ within an ionically crosslinked alginate hydrogel at room temperature and under aerobic conditions using a horseradish peroxidase (HRP)/glucose oxidase (GOx) bienzymatic initiation system. Mechanical testing assessment of the IPN hydrogels confirm mechanical reinforcement via covalent single network interdigitation. Furthermore, the thermosensitive bioink can be used to print biohybrid reactors containing genetically engineered phosphotriesterase‐expressing E. coli capable of hydrolyzing toxic organophosphorus compounds. Herein, increasing the bioink pore size using the contractile‐thermosensitive response of the IPN improves the temperature‐dependent theoretical mass‐transfer‐limited enzyme catalyzed reaction rate, providing a plausible route to externally regulated enzymatic catalysis within bioprinted structures. [ABSTRACT FROM AUTHOR]

Nanomaterial composition, morphology, and mechanical performance are critical parameters for tissue engineering. Within this rapidly expanding space, tubular nanomaterials (TNs), including carbon nanotubes (CNTs), titanium oxide nanotubes (TNTs), halloysite nanotubes (HNTs), silica nanotubes (SiNTs), and hydroxyapatite nanotubes (HANTs) have shown significant potential across a broad range of applications due to their high surface area, versatile surface chemistry, well-defined mechanical properties, excellent biocompatibility, and monodispersity. These include drug delivery vectors, imaging contrast agents, and scaffolds for bone tissue engineering. This review is centered on the recent developments in TN-based biomaterials for structural tissue engineering, with a strong focus on bone tissue regeneration. It includes a detailed literature review on TN-based orthopedic coatings for metallic implants and composite scaffolds to enhance in vivo bone regeneration. [ABSTRACT FROM AUTHOR]

One of the objectives of Curriculum 2000 is to increase the breadth of the curriculum followed by 16-19 year olds. In this paper A level and AS uptake for the years 2001 and 2002 are considered. There was considerable diversity in the uptake of A levels, with nearly 21,000 different combinations of A levels being present in 2002 A level results. Although it is true that biology, chemistry and mathematics is the most common combination of A levels, only 2.2 per cent of candidates took this precise combination. There has been a decline in the percentage of candidates taking three science A levels. In 2002, when only A levels are considered, 35 per cent of candidates could be described as specialists, falling to 21 per cent when AS results are included. AS qualifications appear to have been successful in broadening the curriculum.

This article demonstrates the feasibility of making a partially buried micro gas chromatography ([micro]-GC) column with a rounded channel wall profile, which enables coaling the stationary phase more uniformly and shows better separation characteristics than a square deep reactive ion etched (DRIE) wall profile. A buried structure fabrication method was adapted to fabricate 34 cm long, 165 [micro]m wide, and 65 [micro]m deep partially buried microcolumns, which had a unique rounded microcolumn wall profile similar to that of a flattened circular tube. The separation characteristics were compared to that of a 34 cm long, 100 [micro]m x 100 [micro]m square DRIE microcolumn, which had a similar hydraulic diameter. Minimum height equivalent to a theoretical plate (HETP) and reduced HETP of 0.39 mm and 6.02, respectively, with a retention factor of 6.3 were obtained on the coated partially buried microcolumn compared to 0.66 mm and 6.73, respectively, on the coated square DRIE microcolumn with a similar retention factor. The partially buried microcolumn was found to perform closer to the theoretical approximation and this could be attributed to the uniform phase deposition in the partially buried microcolumn compared to the square DRIE microcolumn. A 10 component mix was separated on the partially buried microcolumn in 3.8 s with the maximum peak width at half-height equal to 0.2 s, while a similar mix separated at higher pressure and temperature conditions on the square DRIE microcolumn in 4.6 s. The rounded comers allowed depositing thinner stationary phase, which was reflected in the faster elution of n-C12 on the partially buried microcolumn compared to the square DRIE microcolumn. The better performance of the partially buried microcolumn may be attributed to either the rounded channel wall profile, the clean channel structures produced by the fabrication process, or the double-etched wall profile, which lowers the Taylor-Ads dispersion.

Microscale total analysis systems ([micro]TAS) allow high-throughput analyses by integrating multiple processes, parallelization, and automation. Here we combine unit operations of [micro]TAS to create a device that can perform multidimensional separations using a three-dimensional hybrid microfluidic/nanofluidic device composed of alternating layers of patterned poly(methyl methacrylate) and nanocapillary array membranes constructed from nuclear track-etched polycarbonate. Two consecutive electrophoretic separations are performed, the first being an achiral separation followed by a chiral separation of a selected analyte band. Separation conditions are optimized for a racemic mixture of fluorescein-isothiocynate-labeled amino acids, serine and aspartic acid, chosen because there are endogenous D-forms of these amino acids in animals. The chiral separation is implemented using micellar electrokinetic chromatography using [beta]-cyclodextrin as the chiral selector and sodium taurocholate as the micelle-forming agent. Analyte separation is monitored by dual-beam laser-induced fluorescence detection. After separation in the first electrophoretic channel, the preselected analyte is sampled by the second-stage separation using an automated collection sequence with a zero-crossing algorithm. The controlled fluidic environment inherent to the three-dimensional architecture enables a series of separations in varying fluidic environments and allows sample stacking via different background electrolyte pH conditions. The ability to interface sequential separations, selected analyte capture, and other fluidic manipulations in the third dimension significantly improves the functionality of multilayer microfluidic devices.

We report microfabrication of a millimeter-scale fuel cell with onboard fuel and a passive control mechanism. This unique power source has a total volume of 9 [micro]L (3 x 3 x 1 [mm.sup.3]), which makes it the smallest fully integrated fuel cell reported in the literature. The first generation of this device delivered an energy density of 254 W x h/L. The device uses a reaction between a metal hydride, LiA1[H.sub.4], and water vapor to generate hydrogen in a reactor. The generated hydrogen exits the reactor through a nanoporous silicon wall to reach a hybrid silicon/Nation membrane electrode assembly. A passive micro-fluidic control system regulates hydrogen generation through controlled delivery of water vapor to the metal hydride based on the reactor pressure. The development of this unique power source greatly benefits the portable electronics industry and enables future technologies that require significantly high energy density power sources such as cognitive arthropods ('thinking' insect-sized robots). This paper provides details of the device micro-fabrication processes, component integration, and performance analysis. [2008-0168] Index Terms--Fuel cell, hydrogen generation, metal hydride, microvalve, power source, power source for portable electronics.

This article demonstrates how to prepare microfabricated columns (microcolumns) for organophosphonate and organosulfur compound separation that rival the performance of commercial capillary columns. Approximately 16 500 theoretical plates were generated with a 3 m long OV-5-coated microcolumn with a 0.25 [micro]m phase thickness using helium as the carrier gas at 20 cm/s. Key to the advance was the development of deactivation procedures appropriate for silicon microcolumns with Pyrex tops. Active sites in a silicon-Pyrex microcolumn cause peak tailing and unwanted adsorption. Experimentally, we found that organosilicon hydride deactivation lowers adsorption activity in microcolumns more than silazane and silane treatments. But without further treatment, the phosphonate peaks continue to tail after the coating process. We found that heat treatment with pinacolyl methylphosphonic acid (PMP) eliminated the phosphonate peak tailing. In contrast, conventional resilylation employing N,O-bis(trimethylsilyl)acetamide, hexamethyldisilazane, and 1-(trimethylsilyl)imidazole does not eliminate peak tailing. Column activity tests show that the PMP treatment also improves the peaks for 2,6-dimethyl aniline, 1-octanol, and 1-decanol implying a decrease in the column's hydrogen bonding sites with the PMP treatment. FT-IR analysis shows that exposure to PMP forms a bond to the stationary phase that deactivates the active sites responsible for organophosphonate peak tailing.