Interactions in Sociotechnical Systems: Achieving Balance in the Use of an Augmented Reality Mobile Application.

OBJECTIVE: We explore relationships between barriers and facilitators experienced by users to understand dynamic interactions in sociotechnical systems and improve a mobile phone-based augmented reality application that teaches users about the contents of a standardized pediatric code cart. BACKGROUND: Understanding interactions between performance obstacles and facilitators can provide guidance to (re)designing sociotechnical systems to improve system outcomes. Clinicians should know about contents and organization of code carts, and an augmented reality mobile application may improve that knowledge but changes the sociotechnical system in which they learn. Prior work identified barriers and facilitators impacting the use of this application-participants described dimensions together, indicating interactions that are explored in the current study. METHOD: We conducted four focus groups (number of clinicians = 18) and two interviews with clinicians who used the application. We performed a secondary analysis of focus group data exploring interactions between previously identified barriers and facilitators to application use. We used epistemic network analysis to visualize these interactions. RESULTS: Work system barriers interacted with barriers and facilitators interacted with facilitators to amplify cumulative negative or positive impact, respectively. Facilitators balanced barriers, mitigating negative impact. Facilitators also exacerbated barriers, worsening negative impact. CONCLUSION: Barriers and facilitators interact and can amplify, balance, and exacerbate each other-notably, positives are not always positive. To obtain desired outcomes, interactions must be further considered in sociotechnical system design, for example, the potential improvements to the application we identified.

Walking the line: balancing performance barriers and facilitators in an augmented reality mobile application for paediatric code cart training.

An augmented reality (AR) mobile smartphone application was developed for clinicians to improve their knowledge about the contents and organisation of a standardised paediatric code cart, an important tool in safe, effective paediatric resuscitations. This study used focus groups and interviews with 22 clinicians to identify work system barriers and facilitators to use of the application. We identified twelve dimensions of barriers and facilitators: convenience, device ownership, device size and type, gamification, interface design, movement/physical space, perception of others, spatial presence, technological experience, technological glitches, workload, and the perception and attitude towards code cart and resuscitation. These dimensions can guide improvement efforts, e.g. redesigning the interface, providing non-AR modes, improving the tutorial. We propose nine principles to guide the design of other digital health technologies incorporating AR. In particular, the workload demands created by using AR must be considered and accounted for in the design and implementation of such technologies. Practitioner summary: Augmented reality (AR) may prepare workers for situations that do not occur frequently. This study investigates barriers and facilitators to using an AR mobile smartphone application developed to improve clinician knowledge about code carts, leading to improvements to the application and principles to guide the design of other AR-based technologies.

SARS-CoV-2 Spike Pseudoviruses: A Useful Tool to Study Virus Entry and Address Emerging Neutralization Escape Phenotypes.

SARS-CoV-2 genetic variants are emerging around the globe. Unfortunately, several SARS-CoV-2 variants, especially variants of concern (VOCs), are less susceptible to neutralization by the convalescent and post-vaccination sera, raising concerns of increased disease transmissibility and severity. Recent data suggests that SARS-CoV-2 neutralizing antibody levels are a reliable correlate of vaccine-mediated protection. However, currently used BSL3-based virus micro-neutralization (MN) assays are more laborious, time-consuming, and expensive, underscoring the need for BSL2-based, cost-effective neutralization assays against SARS-CoV-2 variants. In light of this unmet need, we have developed a BSL-2 pseudovirus-based neutralization assay (PBNA) in cells expressing the human angiotensin-converting enzyme-2 (hACE2) receptor for SARS-CoV-2. The assay is reproducible (R2 = 0.96), demonstrates a good dynamic range and high sensitivity. Our data suggest that the biological Anti-SARS-CoV-2 research reagents such as NIBSC 20/130 show lower neutralization against B.1.351 SA (South Africa) and B.1.1.7 UK (United Kingdom) VOC, whereas a commercially available monoclonal antibody MM43 retains activity against both these variants. SARS-CoV-2 spike PBNAs for VOCs would be useful tools to measure the neutralization ability of candidate vaccines in both preclinical models and clinical trials and would further help develop effective prophylactic countermeasures against emerging neutralization escape phenotypes.

Stable Particle Acceleration in Coaxial Plasma Channels.

The attainable transformer ratio in plasma accelerators is limited by instabilities. Using three-dimensional particle-in-cell simulations, we demonstrate that these can be controlled using a hollow plasma channel with a coaxial plasma filament. The driver scatters electrons from the filament, and the slow pinch of the ions leads to a strong chirp of the effective betatron frequency, preventing beam breakup. We demonstrate the monoenergetic acceleration of an electron bunch to 20 GeV over 4.4 m, achieving a transformer ratio of 10, an energy efficiency of 40%, and an emittance of 1.8 µm.

Influences upon the lead isotopic composition of organic and mineral horizons in soil profiles from the National Soil Inventory of Scotland (2007-09).

Some 644 individual soil horizons from 169 sites in Scotland were analyzed for Pb concentration and isotopic composition. There were three scenarios: (i) 36 sites where both top and bottom (i.e. lowest sampled) soil horizons were classified as organic in nature, (ii) 67 with an organic top but mineral bottom soil horizon, and (iii) 66 where both top and bottom soil horizons were mineral. Lead concentrations were greater in the top horizon relative to the bottom horizon in all but a few cases. The top horizon (206)Pb/(207)Pb ratio was lesser (outside analytical error) than the corresponding bottom horizon (206)Pb/(207)Pb ratio at (i) 64%, (ii) 94% and (iii) 73% of sites, and greater at only (i) 8%, (ii) 3% and (iii) 8% of sites. A plot of (208)Pb/(207)Pb vs. (208)Pb/(206)Pb ratios showed that the Pb in organic top (i, ii) and bottom (i) horizons was consistent with atmospherically deposited Pb of anthropogenic origin. The (206)Pb/(207)Pb ratio of the organic top horizon in (ii) was unrelated to the (206)Pb/(207)Pb ratio of the mineral bottom horizon as demonstrated by the geographical variation in the negative shift in the ratio, a result of differences in the mineral horizon values arising from the greater influence of radiogenic Pb in the north. In (iii), the lesser values of the (206)Pb/(207)Pb ratio for the mineral top horizon relative to the mineral bottom horizon were consistent with the presence of anthropogenic Pb, in addition to indigenous Pb, in the former. Mean anthropogenic Pb inventories of 1.5 and 4.5 g m(-2) were obtained for the northern and southern halves of Scotland, respectively, consistent with long-range atmospheric transport of anthropogenic Pb (mean (206)Pb/(207)Pb ratio~1.16). For cultivated agricultural soils (Ap), this corresponded to about half of the total Pb inventory in the top 30 cm of the soil column.

My 40-Year History with Cronobacter/Enterobacter sakazakii - Lessons Learned, Myths Debunked, and Recommendations.

Much has been learned about organism in the Cronobacter/Enterobacter sakazakii complex since I first named and described Enterobacter sakazakii in 1980. However, there are still wide knowledge gaps. One of the most serious is that are still many uncertainties associated with assessing the public health risk posed by these bacteria, particularly in neonatal meningitis. Over the last few decades, Cronobacter contamination of commercial powdered infant formula products has apparently been reduced, but it is still an ongoing problem. The powdered infant formula industry still cannot produce powdered formula that is free of bacterial contamination with Cronobacter, other Enterobacteriaceae, other pathogenic bacteria, and other microorganisms. Until this happens, infants and other will be at risk of becoming infected when they ingest contaminated formula.

Mobility of antimony, arsenic and lead at a former antimony mine, Glendinning, Scotland.

Elevated concentrations of antimony (Sb), arsenic (As) and lead (Pb) in upland organic-rich soils have resulted from past Sb mining activities at Glendinning, southern Scotland. Transfer of these elements into soil porewaters was linked to the production and leaching of dissolved organic matter and to leaching of spoil material. Sb was predominantly present in truly dissolved (<3 kDa) forms whilst As and Pb were more commonly associated with large Fe-rich/organic colloids. The distinctive porewater behaviour of Sb accounts for its loss from deeper sections of certain cores and its transport over greater distances down steeper sections of the catchment. Although Sb and As concentrations decreased with increasing distance down a steep gully from the main spoil heap, elevated concentrations (~6-8 and 13-20 µg L(-1), respectively) were detected in receiving streamwaters. Thus, only partial attenuation occurs in steeply sloping sections of mining-impacted upland organic-rich soils and so spoil-derived contamination of surface waters may continue over time periods of decades to centuries. CAPSULE ABSTRACT: Production and leaching of dissolved organic matter led to the concomitant transfer of truly dissolved Sb to soil porewaters. Leaching of spoil-derived Sb impacted on the quality of receiving stream waters.

Dynamics of maize carbon contribution to soil organic carbon in association with soil type and fertility level.

Soil type and fertility level influence straw carbon dynamics in the agroecosystems. However, there is a limited understanding of the dynamic processes of straw-derived and soil-derived carbon and the influence of the addition of straw carbon on soil-derived organic carbon in different soils associated with different fertility levels. In this study, we applied the in-situ carborundum tube method and 13C-labeled maize straw (with and without maize straw) at two cropland (Phaeozem and Luvisol soils) experimental sites in northeast China to quantify the dynamics of maize-derived and soil-derived carbon in soils associated with high and low fertility, and to examine how the addition of maize carbon influences soil-derived organic carbon and the interactions of soil type and fertility level with maize-derived and soil-derived carbon. We found that, on average, the contributions of maize-derived carbon to total organic carbon in maize-soil systems during the experimental period were differentiated among low fertility Luvisol (from 62.82% to 42.90), high fertility Luvisol (from 53.15% to 30.00%), low fertility Phaeozem (from 58.69% to 36.29%) and high fertility Phaeozem (from 41.06% to 16.60%). Furthermore, the addition of maize carbon significantly decreased the remaining soil-derived organic carbon in low and high fertility Luvisols and low fertility Phaeozem before two months. However, the increasing differences in soil-derived organic carbon between both soils with and without maize straw after two months suggested that maize-derived carbon was incorporated into soil-derived organic carbon, thereby potentially offsetting the loss of soil-derived organic carbon. These results suggested that Phaeozem and high fertility level soils would fix more maize carbon over time and thus were more beneficial for protecting soil-derived organic carbon from maize carbon decomposition.

Arabidopsis AtSUC2 and AtSUC4, encoding sucrose transporters, are required for abiotic stress tolerance in an ABA-dependent pathway.

Sucrose transporters (SUCs or SUTs) play a central role, as they orchestrate sucrose allocation both intracellularly and at the whole plant level. Previously, we found AtSUC4 mutants changing sucrose distribution under drought and salt stresses. Here, we systematically examined the role of Arabidopsis AtSUC2 and AtSUC4 in response to abiotic stress. The results showed significant induction of AtSUC2 and AtSUC4 in salt, osmotic, low temperature and exogenous abscisic acid (ABA) treatments by public microarray data and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analyses. The loss-of-function mutation of AtSUC2 and AtSUC4 led to hypersensitive responses to abiotic stress and ABA treatment in seed germination and seedling growth. These mutants also showed higher sucrose content in shoots and lower sucrose content in roots, as compared with that in wild-type plants, and inhibited the ABA-induced expression of many stress- and ABA-responsive genes, especially ABFs and ABF-downstream and upstream genes. The loss-of-function mutant of AtSUC3, a unique putative sucrose sensor, reduced the expression of AtSUC2 and AtSUC4 in response to abiotic stresses and ABA. These findings confirmed that AtSUC2 and AtSUC4 are important regulators in plant abiotic stress tolerance that use an ABA signaling pathway, which may be crossed with sucrose signaling.

Geochemical associations and availability of cadmium (Cd) in a paddy field system, northwestern Thailand.

The Mae Tao watershed, northwest Thailand, has become contaminated with cadmium (Cd) as a result of zinc ore extraction (Padaeng deposit) in the nearby Thanon-Thongchai mountains. Consumption of contaminated rice has led to documented human health impacts. The aim of this study was to elucidate transfer pathways from creek and canal waters to the paddy field soils near Baan Mae Tao Mai village and to determine the relationship between Cd speciation in the soil and uptake by rice plants. Transfer mainly occurred in association with particulate matter during flooding and channel dredging and, in contrast with many other studies, most of the soil Cd was associated with exchangeable and carbonate-bound fractions. Moreover, there was a linear relationship between soil total Cd and rice grain Cd (R(2) = 0.715), but a stronger relationship between both the Tessier-exchangeable soil Cd and the BCR-exchangeable soil Cd and rice grain Cd (R(2) = 0.898 and 0.862, respectively).

Arterial stiffness as a risk factor for coronary artery disease.

Hypertension is a major modifiable risk factor, and clinical trials have demonstrated that successful reduction of elevated blood pressure to target levels translates into decreased risk for the development of coronary artery disease, stroke, heart failure, and renal failure. The arterial system had previously been regarded as a passive conduit for the transportation of arterial blood to peripheral tissues. The physiologic role the arterial system was greatly expanded by the recognition of the central role of the endothelial function in a variety of physiologic processes. The role of arterial function and structure in cardiovascular physiology was expanded with the development of a variety of parameters that evaluate arterial stiffness. Markers of arterial stiffness have been correlated with cardiovascular outcomes, and have been classified as an emerging risk factor that provides prognostic information beyond standard stratification strategies involving hypertension, diabetes, obesity, dyslipidemia and smoking. Multiple epidemiologic studies have correlated markers of arterial stiffness such as pulse-wave velocity, augmentation index and pulse pressure with risk for the development of fatal and nonfatal cardiovascular events. Additionally, measurements of arterial stiffness had clarified the results of clinical trials that demonstrated differing impacts on clinical outcomes, despite similar reductions in blood pressure, as measured by brachial and sphygmomanometry.

Validation of an eight parameter immunophenotyping panel in adult canines for assessment of immunotoxicity.

Analysis of peripheral blood leukocyte populations by flow cytometry in adult beagles is a critical component of immunotoxicity assessment in regulated pre-clinical toxicology studies. In this study, data is presented utilizing a single panel, six-color method to simultaneously enumerate absolute cell counts and determine the relative percentage of leukocytes. A GLP validation was performed to determine intra- and inter-assay variance, inter-instrument variance, and pre- and post-fixation stability for the target populations. The results demonstrated all samples met acceptance criteria, CV values less than 25%, for all precision and stability intervals assessed. The intra and inter-assay data demonstrated the single panel method generated acceptable precision. Furthermore, stability results indicated whole blood samples and processed samples may be stored without a statistically significant difference in the data compared to samples immediately processed and analyzed after blood collection. This assay will provide researchers a more precise and efficient tool to evaluate the immunotoxic effects of a test article on canine peripheral blood leukocytes during pre-clinical drug testing.

Association between preoperative diuretic use and in-hospital outcomes after cardiac surgery.

BACKGROUND: There is a paucity of evidence on the association between preoperative diuretics use and outcomes following cardiac surgery. We hypothesized that diuretic use prior to cardiac surgery will be associated with adverse in-hospital clinical outcomes. METHODS: We evaluated patients undergoing cardiac surgery at a single institution between January 1, 2000, and December 31, 2011. Patients were grouped as follows: isolated coronary artery bypass grafting (CABG) (n = 8759), CABG plus valve surgery (n = 1188), and valve surgery only (n = 2646). A fourth group "All cardiac surgery" is comprised of patients from all three groups. Preoperative diuretic use was defined as patient on any diuretic till the day of surgery. Primary outcome was the incidence of major adverse events (MAEs) defined as the composite of mortality, postoperative renal dysfunction, myocardial infarction, stroke, and new-onset atrial fibrillation (AF). Logistic regression analysis and propensity score matching were performed. RESULTS: We included 12,593 patients [3546 on diuretic (28%)]. After logistic regression analyses, preoperative diuretic use was associated with an increased risk of the following: (1) MAE among all groups except the concomitant CABG and valve surgery group, (2) AF in "All cardiac surgery" and isolated CABG groups, (3) postoperative renal dysfunction in all groups. After propensity score matching (n = 3050 in each group), preoperative diuretic use was significantly associated with MAE (48% vs. 43%; P < 0.0001), postoperative renal dysfunction (19% vs. 14%; P < 0.0001), and AF (34% vs. 32%; P = 0.03) in the "All cardiac surgery" group. CONCLUSION: Preoperative diuretics use is associated with an increased incidence of MAEs after cardiac surgery.

Aggressive statin therapy and the risk of malignancy.

The advent of pharmacologic agents which partially inhibit the rate limiting enzyme in cholesterol synthesis (3-hydroxy-3-methylglutaryl Co-A reductase) provided a major advance in preventive medicine. Clinical trials in both primary and secondary prevention have demonstrated reduction in cardiovascular events by statin therapy. However, early epidemiologic studies proposed an inverse relationship between cholesterol levels and mortality. While the epidemiologic studies were controversial and did not establish a cause and effect relationship, concern was raised that aggressive lipid lowering by pharmacological means may be associated with increased risk for noncardiac mortality, including malignancy. The theoretical concern was intensified by meta-analysis of statin trials, which confirmed the reduction in cardiovascular mortality but also demonstrated a potential increase in cancer risk. This review evaluates the epidemiologic and prospective trial data which address the potential relationship between aggressive statin therapy and the risk of malignancy.

Metabolic syndrome in South Asians.

Metabolic syndrome (MS) is a cluster of multiple cardio-metabolic risk factors in the same individual. People with MS are at high risk for the development of cardiovascular disease (CVD), chronic kidney disease (CKD), and cerebrovascular disease (CeVD). The excessive presence of MS in South Asians is likely responsible for significant morbidity in this population. This review discusses the scope of MS in South Asians and measures to combat its effects by preventive and therapeutic measures.

High-density lipoprotein and atherosclerosis: the role of antioxidant activity.

Levels of high-density lipoprotein (HDL) cholesterol are generally inversely associated with the risk for the development of atherosclerosis. The mechanism by which HDL imparts protection from the initiation and progression of occlusive vascular disease is complex and multifactorial. The major anti-atherosclerotic effect of HDL is felt to be reverse cholesterol transport. HDL has been demonstrated to scavenge cholesterol from the peripheral vasculature with transport to the liver, where is it excreted in the biliary system. However, HDL exhibits multiple other physiologic effects that may play a role in the reduced risk for atherosclerosis. HDL has been demonstrated to exhibit beneficial effects on platelet function, endothelial function, coagulation parameters, inflammation, and interactions with triglyceride-rich lipoproteins. Increasing amounts of clinical and experimental data have shown that HDL cholesterol has significant antioxidant effect that may significantly contribute to protection from atherosclerosis.

Processes controlling manganese distributions and associations in organic-rich freshwater aquatic systems: the example of Loch Bradan, Scotland.

Recent increases in manganese (Mn) concentrations in surface waters, including drinking water supplies, have triggered renewed interest in its geochemical behaviour in freshwater systems. This study, involving analysis of bottom sediments and ultrafiltered water (stream, loch and sediment porewater) samples, identified changes in aqueous phase speciation of Mn upon entering the loch waters and during its transit from the inflow to the outflow of Loch Bradan, a drinking water reservoir in SW Scotland. Diffusion out of the bottom sediments during calm periods or mixing of porewaters with loch water during resuspension events also released Mn into the overlying waters. Although 65% Mn was in colloidal form (3 kDa-0.2 µm) in the main streamwater inflow at the western end, 57-66% was present in the <3 kDa fraction in the proximal loch waters, at least partly as a result of the release of Mn(2+) from the bottom sediments. Towards the outflow at the eastern end, however, the increase in the amount of Mn associated with large organic colloids (100 kDa-0.2 µm) correlated with the speciation of Mn in the bottom water and the bottom sediment porewaters. While the inflow waters do have some impact upon Mn speciation at the western end of the loch, it appears that within-loch processes have a greater impact on Mn speciation near the outflow. These findings emphasise the importance of understanding the geochemical controls on Mn behaviour in aquatic systems: it is clear that although Mn may be present as truly dissolved Mn(2+) in some parts of the loch, it can also be associated to a significant extent (35-47%) with large organic colloids. These findings are important not only with respect to water treatment but also in terms of understanding the likely consequences of climatic change which may exacerbate losses of Mn from the bottom sediments.

Type 2 diabetes and cardiovascular risk factors.

Diabetes is associated with higher cardiovascular morbidity and mortality. Hypertension, hyperlipidemia and diabetes are independently associated with increased risk of cardiovascular (CV) disease. Subjects with type 2 diabetes are at two- to four-fold increased risk of CV disease compared to those without diabetes. Long-term hyperglycemia is much more closely associated with microvascular complications than macrovascular complications. There is a lack of adequate evidence that improvement in glycemic control decreases CV risk.