TAP reactor investigation of methane coupling over samarium oxide catalysts

The adsorption and reaction characteristics of a Ba/Sr/Sm2O3 catalyst for methane coupling has been investigated using the TAP (Temporal Analysis of Products) reactor system. Pulsed adsorption experiments using methane, oxygen and krypton at temperatures ranging from 17°C to 800°C show that the transient response of methane is similar to that of Kr and is either not adsorbed, or weakly adsorbed on the catalyst. By contrast, oxygen is strongly adsorbed at temperatures above 500°C which suggests incorporation into the lattice with possible formation of surface anions. Pump-probe experiments in which methane and oxygen are introduced over the catalyst were also performed to investigate the effect of lifetimes of suspected surface intermediates on the relative yields of ethane and ethene. It is shown that the relative yields of both species increase with increasing values of the pulse valve time delay between introduction of the oxygen and methane. An explanation of these results using current knowledge and reasonable speculation of the mechanism is provided

Phages & antibiotic resistance: are the most abundant entities on earth ready for a comeback?

Bacteriophages, which lost out to antibiotic therapy in the past, may be poised to make a comeback. Once discarded because of their narrow activity spectrum, it can now be viewed as a major advantage that these intracellular, self-replicating entities can exert their killing effect with minimal damage to the commensal microbiome. In eastern Europe, phages continue to be used both prophylactically and therapeutically to treat infections. More recently, much needed regulated clinical trials are underway with a view to restoring phage therapy as a tool for mainstream medicine, although current regulations may impede their full potential. One hundred years after their discovery, and amid an antibiotic resistance crisis, we must ask, what can be done to harness their full antibacterial potential

Health food store recommendations: implications for breast cancer patients

BACKGROUND: Many breast cancer patients use complementary and alternative medicine (CAM). We aimed to determine what advice health food store employees present to individuals seeking treatment options for breast cancer. METHODS: Eight data gatherers asked employees of all retail health food stores in a major Canadian city, what they recommended for a patient with breast cancer. The data gatherers inquired about product safety, potential drug interactions, costs and efficacy. They also enquired about employee training related to the products. RESULTS: Thirty-four stores were examined. A total of 33 different products were recommended, none of which are supported by sufficient evidence of efficacy. The average cost of the products they recommended was $58.09 (CAD) (minimum$5.28, median $32.99, maximum$600) per month. Twenty-three employees (68%) did not ask whether the patient took prescription medications. Fifteen employees (44%) recommended visiting a healthcare professional (naturopaths (9), physicians (5), nutritionists (1). Three employees (8.8%) discussed potential adverse effects of the products. Eight employees (23.5%) discussed the potential for drug interactions. Two employees (5.9%) suggested a possible cure with the products and one employee (2.9%) suggested discontinuing Tamoxifen. Four employees (11.8%) recommended lifestyle changes and three employees (8.8%) recommended books for further reading on the products. CONCLUSION: This study draws attention to the heterogeneity of advice provided by natural health food stores to individuals seeking treatments for breast cancer, and the safety and cost implications of some of the products recommended. Physicians should enquire carefully about the use of natural health food products by patients with breast cancer. Regulators need to consider regulations to protect vulnerable patients from incurring significant costs in their purchasing of natural health food products lacking evidence of benefit and of questionable safety

Application-motivated, holistic benchmarking of a full quantum computing stack

Quantum computing systems need to be benchmarked in terms of practical tasks they would be expected to do. Here, we propose 3 "application-motivated" circuit classes for benchmarking: deep (relevant for state preparation in the variational quantum eigensolver algorithm), shallow (inspired by IQP-type circuits that might be useful for near-term quantum machine learning), and square (inspired by the quantum volume benchmark). We quantify the performance of a quantum computing system in running circuits from these classes using several figures of merit, all of which require exponential classical computing resources and a polynomial number of classical samples (bitstrings) from the system. We study how performance varies with the compilation strategy used and the device on which the circuit is run. Using systems made available by IBM Quantum, we examine their performance, showing that noise-aware compilation strategies may be beneficial, and that device connectivity and noise levels play a crucial role in the performance of the system according to our benchmarks

Quantification of opportunities for early-stage paramedicine students to practice clinical skills during clinical placements compared with an equal dose of simulation-based workshops

Introduction A reported advantage of simulation-based learning environments (SLE) over clinical placements (CPs) is that the former can provide a greater number and breadth of opportunities to practice level-appropriate clinical skills compared with the random patient presentations provided during the latter. Although logical and widely accepted as fact, we find no published evidence to demonstrate the magnitude, nor indeed veracity, of this assumption. We therefore sought to quantify the clinical skills practiced by entry-level paramedicine students attending a well-selected CP compared with an equal dosage of SLE. Methods N=37 first-year paramedicine students completed activity diaries during 3 days of CP and 3 days of SLE. Opportunities to practice clinical skills were quantified and coded as either: level-appropriate, beyond-level or of non-discipline relevance. Results During SLE, the average student was exposed 226 times to 11 level-appropriate clinical procedures. During CP the average student was exposed 48 times to 24 clinical procedures, the majority relevant to paramedicine (63%), but a minority level-appropriate (38%). Students’ opportunities for supervised, ‘hands on’ practice represented only 10% of exposures in either SLE or CP but in terms of raw numbers of level-appropriate opportunities, SLE provided more than CP (n=23 vs 2). Discussion Our results confirm that SLE provides substantially more opportunities than CP for students to practice level-appropriate skills and is therefore more appropriate for repetitive practice. However, CP is likely to remain useful to students for practicing interpersonal skills and contextualisation of knowledge within the broader health system. Educators should therefore carefully articulate learning objectives before choosing between SLE and CP

Selective Myeloid Depletion of Galectin-3 Offers Protection Against Acute and Chronic Lung Injury

Rationale: Galectin-3 (Gal-3) is an immune regulator and an important driver of fibrosis in chronic lung injury, however, its role in acute lung injury (ALI) remains unknown. Previous work has shown that global deletion of galectin-3 reduces collagen deposition in a bleomycin-induced pulmonary fibrosis model (MacKinnon et al., Am. J. Respir. Crit. Care Med., 2012, 185, 537–46). An inhaled Gal-3 inhibitor, GB0139, is undergoing Phase II clinical development for idiopathic pulmonary fibrosis (IPF). This work aims to elucidate the role of Gal-3 in the myeloid and mesenchymal compartment on the development of acute and chronic lung injury. Methods:LgalS3(fl/fl) mice were generated and crossed with mice expressing the myeloid (LysM) and mesenchymal (Pdgfrb) cre drivers to yield LysM-cre (+/-) /LgalS3 (fl/fl) and Pdgfrb-cre (+/-) /LgalS3 (fl/fl) mice. The response to acute (bleomycin or LPS) or chronic (bleomycin) lung injury was compared to globally deficient Gal-3 (−/−) mice. Results: Myeloid depletion of Gal-3 led to a significant reduction in Gal-3 expression in alveolar macrophages and neutrophils and a reduction in neutrophil recruitment into the interstitium but not into the alveolar space. The reduction in interstitial neutrophils corelated with decreased levels of pulmonary inflammation following acute bleomycin and LPS administration. In addition, myeloid deletion decreased Gal-3 levels in bronchoalveolar lavage (BAL) and reduced lung fibrosis induced by chronic bleomycin. In contrast, no differences in BAL Gal-3 levels or fibrosis were observed in Pdgfrb-cre (+/-) /LgalS3 (fl/fl) mice. Conclusions: Myeloid cell derived Galectin-3 drives acute and chronic lung inflammation and supports direct targeting of galectin-3 as an attractive new therapy for lung inflammation

Enhancing the stress responses of probiotics for a lifestyle from gut to product and back again

Before a probiotic bacterium can even begin to fulfill its biological role, it must survive a battery of environmental stresses imposed during food processing and passage through the gastrointestinal tract (GIT). Food processing stresses include extremes in temperature, as well as osmotic, oxidative and food matrix stresses. Passage through the GIT is a hazardous journey for any bacteria with deleterious lows in pH encountered in the stomach to the detergent-like properties of bile in the duodenum. However, bacteria are equipped with an array of defense mechanisms to counteract intracellular damage or to enhance the robustness of the cell to withstand lethal external environments. Understanding these mechanisms in probiotic bacteria and indeed other bacterial groups has resulted in the development of a molecular toolbox to augment the technological and gastrointestinal performance of probiotics. This has been greatly aided by studies which examine the global cellular responses to stress highlighting distinct regulatory networks and which also identify novel mechanisms used by cells to cope with hazardous environments. This review highlights the latest studies which have exploited the bacterial stress response with a view to producing next-generation probiotic cultures and highlights the significance of studies which view the global bacterial stress response from an integrative systems biology perspective

Volumetric Benchmarking of Error Mitigation with Qermit

The detrimental effect of noise accumulates as quantum computers grow in size. In the case where devices are too small or noisy to perform error correction, error mitigation may be used. Error mitigation does not increase the fidelity of quantum states, but instead aims to reduce the approximation error in quantities of concern, such as expectation values of observables. However, it is as yet unclear which circuit types, and devices of which characteristics, benefit most from the use of error mitigation. Here we develop a methodology to assess the performance of quantum error mitigation techniques. Our benchmarks are volumetric in design, and are performed on different superconducting hardware devices. Extensive classical simulations are also used for comparison. We use these benchmarks to identify disconnects between the predicted and practical performance of error mitigation protocols, and to identify the situations in which their use is beneficial. To perform these experiments, and for the benefit of the wider community, we introduce Qermit - an open source python package for quantum error mitigation. Qermit supports a wide range of error mitigation methods, is easily extensible and has a modular graph-based software design that facilitates composition of error mitigation protocols and subroutines.Comment: 25 pages, Comments welcom

A Thorough Search for Elusive Lunar Granophyres

Recent remote sensing studies [e.g., 1-3] indicate that several un-sampled regions of the Moon have significantly higher concentrations of silicic material (also high in [K], [U], and [Th]) than sampled regions. Within these areas are morphological features that are best explained by the existence of chemically evolved volcanic rocks. Observations of silicic domes [e.g., 1-5] suggest that sizable networks of silicic melt were present during crust-formation. Because of these recent findings there is a renewed interest in the petrogenesis of lunar, felsic igneous rocks. Specific questions are: (1) when were these magmas generated?, and (2) what was the source material? The two main hypotheses for generating silicic melts on Earth are fractional crystallization or partial melting of preexisting crust. On the Moon silicic melts are thought to have been generated during extreme fractional crystallization involving end-stage silicate liquid immiscibility (SLI) [e.g. 6, 7]. However, SLI cannot account for the production of significant volumes of silicic melt and its wide distribution, as reported by the remote global surveys [1, 2, 3]. In addition, experimental and natural products of SLI show that U and Th, which are abundant in the lunar granites and seen in the remote sensing data of the domes, are preferentially partitioned into the depolymerized ferrobasaltic magma and not the silicic portion [8, 9]. If SLI is not the mechanism that generated silicic magmas on the Moon then alternative processes such as fractional crystallization (only crystal-liquid separation) or partial melting should be considered as viable possibilities to be tested