Exponential Qubit Reduction in Optimization for Financial Transaction Settlement

We extend the qubit-efficient encoding presented in [Tan et al., Quantum 5, 454 (2021)] and apply it to instances of the financial transaction settlement problem constructed from data provided by a regulated financial exchange. Our methods are directly applicable to any QUBO problem with linear inequality constraints. Our extension of previously proposed methods consists of a simplification in varying the number of qubits used to encode correlations as well as a new class of variational circuits which incorporate symmetries, thereby reducing sampling overhead, improving numerical stability and recovering the expression of the cost objective as a Hermitian observable. We also propose optimality-preserving methods to reduce variance in real-world data and substitute continuous slack variables. We benchmark our methods against standard QAOA for problems consisting of 16 transactions and obtain competitive results. Our newly proposed variational ansatz performs best overall. We demonstrate tackling problems with 128 transactions on real quantum hardware, exceeding previous results bounded by NISQ hardware by almost two orders of magnitude.Comment: 16 pages, 8 figure

Analysis of clogging in constructed wetlands using magnetic resonance

In this work we demonstrate the potential of permanent magnet based magnetic resonance sensors to monitor and assess the extent of pore clogging in water filtration systems. The performance of the sensor was tested on artificially clogged gravel substrates and on gravel bed samples from constructed wetlands used to treat wastewater. Data indicate that the spin lattice relaxation time is linearly related to the hydraulic conductivity in such systems. In addition, within biologically active filters we demonstrate the ability to determine the relative ratio of biomass to abiotic solids, a measurement which is not possible using alternative techniques

A multi-bacteriocin cheese starter system comprising nisin and lacticin 3147 in Lactococcus lactis, in combination with plantaricin from Lactobacillus plantarum

Functional starter cultures demonstrating superior technological and food safety properties are advantageous to the food fermentation industry. We evaluated the efficacy of single and double bacteriocin-producing starters of Lactococcus lactis capable of producing the Class I bacteriocins, nisin A and/or lacticin 3147 in terms of starter performance. Single producers were generated by mobilising the conjugative, bacteriophage resistance plasmid pMRC01, encoding lacticin genetic determinants, or the conjugative transposon Tn5276, encoding nisin genetic determinants, to the commercial starter L. lactis CSK2775. The effect of bacteriocin co-production was examined by superimposing pMRC01 into the newly constructed nisin transconjugant. Transconjugants were improved with regard to antimicrobial activity and bacteriophage insensitivity when compared to the recipient strain and the double producer was immune to both bacteriocins. Bacteriocin production in the starter was stable, although the recipient strain proved to be a more efficient acidifier than transconjugant derivatives. Overall, combining Class I bacteriocins (the double-producer or a combination of single producers) proved as effective as individual bacteriocins for controlling Listeria innocua growth in laboratory-scale cheeses. However, using the double producer in combination with the Class II bacteriocin producer Lactobacillus plantarum, or the lacticin producer with the Class II producer, proved most effective for reducing bacterial load. As emergence of bacteriocin tolerance was reduced 10-fold in the presence of nisin and lacticin, we suggest that the double producer in conjunction with the Class II producer could serve as a protective culture providing a food-grade, multi-hurdle approach to control pathogenic growth in a variety of industrial applications. IMPORTANCE: We generated a suite of single and double-bacteriocin producing starter cultures capable of generating the Class I bacteriocins lacticin 3147 or nisin or both bacteriocins simultaneously via conjugation. The transconjugants exhibited improved bacteriophage resistance and antimicrobial activity. The single producers proved as effective as the double-bacteriocin producer at reducing Listeria numbers in laboratory-scale cheese. However, combining the double producer or the lacticin producing starter with a Class II bacteriocin producer, Lactobacillus plantarum LMG P-26358, proved most effective at reducing Listeria numbers, and was significantly better than a combination of the three bacteriocin producing strains, as the double producer is not inhibited by either of the Class I bacteriocins. Since the simultaneous use of lacticin and nisin should reduce the emergence of bacteriocin tolerant derivatives this study suggests that a protective starter system produced by bacteriocin stacking is a worthwhile multi-hurdle approach for food safety applications

Currently prescribed drugs in the UK that could upregulate or downregulate ACE2 in COVID-19 disease: a systematic review.

Funder: Medical Research Council; FundRef: http://dx.doi.org/10.13039/501100000265; Grant(s): MRC Epidemiology Unit programme: MC_UU_12015/4.OBJECTIVE: To review evidence on routinely prescribed drugs in the UK that could upregulate or downregulate ACE2 and potentially affect COVID-19 disease. DESIGN: Systematic review. DATA SOURCE: MEDLINE, EMBASE, CINAHL, the Cochrane Library and Web of Science. STUDY SELECTION: Any design with animal or human models examining a currently prescribed UK drug compared with a control, placebo or sham group, and reporting an effect on ACE2 level, activity or gene expression. DATA EXTRACTION AND SYNTHESIS: MEDLINE, EMBASE, CINAHL, the Cochrane Library, Web of Science and OpenGrey from inception to 1 April 2020. Methodological quality was assessed using the SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) risk-of-bias tool for animal studies and Cochrane risk-of-bias tool for human studies. RESULTS: We screened 3360 titles and included 112 studies with 21 different drug classes identified as influencing ACE2 activity. Ten studies were in humans and one hundred and two were in animal models None examined ACE2 in human lungs. The most frequently examined drugs were angiotensin receptor blockers (ARBs) (n=55) and ACE inhibitors (ACE-I) (n=22). More studies reported upregulation than downregulation with ACE-I (n=22), ARBs (n=55), insulin (n=8), thiazolidinedione (n=7) aldosterone agonists (n=3), statins (n=5), oestrogens (n=5) calcium channel blockers (n=3) glucagon-like peptide 1 (GLP-1) agonists (n=2) and Non-steroidal anti-inflammatory drugs (NSAIDs) (n=2). CONCLUSIONS: There is an abundance of the academic literature and media reports on the potential of drugs that could attenuate or exacerbate COVID-19 disease. This is leading to trials of repurposed drugs and uncertainty among patients and clinicians concerning continuation or cessation of prescribed medications. Our review indicates that the impact of currently prescribed drugs on ACE2 has been poorly studied in vivo, particularly in human lungs where the SARS-CoV-2 virus appears to enact its pathogenic effects. We found no convincing evidence to justify starting or stopping currently prescribed drugs to influence outcomes of COVID-19 disease

The connectivity of spring stopover sites for geese heading to arctic breeding grounds

During the spring migration arctic-breeding geese pause in temperate and sub-arctic staging areas in order to deposit body reserves for breeding. Focusing on a single arctic stopover site in West-Spitsbergen, Svalbard, Norway (Varsol-bukta, 77 degrees 45'N, 14 degrees 24'E), behavioural strategies of Barnacle Geese Branta leucopsis were investigated and body condition and presence of individually marked birds recorded. Individuals using different staging areas earlier along the migration route (Helgeland and Vesteralen on the Norwegian mainland) and heading to different breeding colonies (the close-by Nordenskioldkysten, and the distant Kongsfjorden) were compared during springs 2003-05. Birds in Vesteralen left the staging area earlier than those in Helgeland, and arrived earlier in Varsolbukta as well. In Varsolbukta, females gained body condition at a similar rate regardless of their colony affiliation, whereas males from Nordenskioldkysten exhibited a smaller overall increase in condition compared to males from Kongsfjorden. The Kongsfjorden birds stayed for a shorter period (average 2.8 days) than those from Nordenskioldkysten (average 4.0 days). Nordenskioldkysten birds frequently left Varsolbukta for short periods presumably visiting the breeding area in order to optimise nest initiation with respect to prevailing snow conditions. The date of final departure was also correlated with nest initiation date at Nordenskioldkysten. No such relationship for the Kongsfjorden birds was found. We suggest that the geese adopt a 'hopping' strategy, using a network of stopover sites in Svalbard during spring with a last stopover at a buffer area in the proximity to the breeding area. For this vulnerable population it is important to identify the sites forming the links in this chain, and to establish their function and utilisation by geese during the vital prebreeding period

Use of matrix-assisted laser desorption ionization-time of flight mass spectrometry to identify vancomycin-resistant enterococci and investigate the epidemiology of an outbreak

The control of vancomycin-resistant enterococci (VRE) has become an increasing burden on health care resources since their discovery over 20 years ago. Current techniques employed for their detection include time-consuming and laborious phenotypic methods or molecular methods requiring costly equipment and consumables and highly trained staff. An accurate, rapid diagnostic test has the ability to greatly reduce the spread of this organism, which has the ability to colonize patients for long periods, potentially even lifelong. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is a technology with the ability to identify organisms in seconds and has shown promise in the identification of other forms of antimicrobial resistance in other organisms. Here we show that MALDI-TOF MS is capable of rapidly and accurately identifying vanB-positive Enterococcus faecium VRE from susceptible isolates. Internal validation of the optimal model generated produced a sensitivity of 92.4% and a specificity of 85.2%. Prospective validation results, following incorporation into the routine laboratory work flow, demonstrated a greater sensitivity and specificity at 96.7% and 98.1%, respectively. In addition, the utilization of MALDI-TOF MS to determine the relatedness of isolates contributing to an outbreak is also demonstrated

Conservation of the Gharial (Gavialis gangeticus) at the Madras Crocodile Bank Trust, Chennai, India

Gavialis gangeticus are in serious decline in the wild. In this short article we provide an overview of Gharial ecology and current conservation measures taking place at the Madras Crocodile Bank Trust in India