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Abstract: Interaction of carbon monoxide (CO) with transition metal surfaces is an essential part of CO oxidation catalysis. In this report, we investigate and compare CO adsorption behavior on Pt (111) and Pd (111) surfaces combining first-principles (FP) calculations and lattice gas Monte-Carlo (LG-MC) simulations. Our results indicate that despite stronger CO binding on Pd (111) at low coverage, more repulsive lateral interactions on Pd surface lead to a more rapid adsorption energy decrease with respect to coverage. This results in lower saturation coverage and weaker CO desorption energies on Pd (111), which could contribute to its excellent reactivity observed under high pressure reaction conditions. [Copyright &y& Elsevier]

Abstract: Combinations of microcrystalline cellulose (MCC) and sodium carboxymethyl cellulose (Na-CMC) are commonly used as stabilising agents and suspending agents in pharmaceutical formulations. This paper is based on a study of the interactions that take place during the process of hydrogel formation, break down, and recovery. Also considered is the binding that occurs between the MCC and the Na-CMC. Avicel RC 591, a processed mixture of MCC and Na-CMC, is one of the more commonly used commercial suspending agents for aqueous compositions. Avicel RC 591 is used as an effective, blended stabilising agent. In this study, the contributions made by each of the components of Avicel RC 591 have been rationalised by monitoring the behaviour of the individual components in Avicel RC 591 suspensions or solutions. The hydrogels that are formed by Avicel RC 591 and by their laboratory formulated equivalent, which is spray dried (MCC+Na-CMC), have been characterised by confocal microscopy scanning electron microscopy and by dynamic light scattering. A 3D network structure that is formed by the MCC, in Avicel RC 591 is visualised. This network is supported by hydrogen bonding and by ionic interactions among and between the MCC, the Na-CMC and water. The strength of the network determines the physical properties of the hydrogel system, as seen in the rheological behaviour. [Copyright &y& Elsevier]

Abstract: A two-dimensional model for predicting the fluid pickout and coated film thickness characteristics of a discrete cell direct gravure roll coater operating in reverse mode is derived. A novel multiscale approach is adopted for this purpose and the resulting equations solved numerically for inertia-less flow conditions. A system of stiff ordinary differential equations is found to be sufficient to capture the major gross flow features, while at the cell level the analysis is based on a finite element solution of the momentum and continuity equations. It represents the first such predictive model of its kind, with particular interest placed on the nature of both the pressure distribution and web-to-roll gap profile spanning the coating bead. The effect of key operating parameters, web-to-roll speed ratio, web-tension, wrap-angle, capillary number and cell-geometry, on the degree of fluid pickout from gravure cells and the coated film thickness is explored. Although an idealised model, the trends observed show qualitative agreement with existing experimental data collected on a small-scale gravure coating rig and point the way forward to the eventual formulation of a full three-dimensional predictive model of the process. [Copyright &y& Elsevier]

Abstract: A mathematical model is presented and solved for the fluid flow within the coating bead of a tri-helical gravure roll coater, operating in reverse mode. A variety of rolls etched circumferentially with grooves of different cross-sectional shape and aligned at non-zero angles of pitch are investigated. Predictions of fluid pick-out from the grooves are compared with complementary experimental data. Quantitative agreement between the two is found to be very good, showing a linear increase in pickout as a function of web-to-roll speed ratio and groove depths up to the point at which streaking, as observed experimentally, occurs and beyond which the model is no longer valid. In regions of parameter space for which there is no experimental data available for comparison purposes the model predicts that: (i) fluid pick-out decreases with increasing groove depth while the film thickness tends to increase and (ii) an increase in groove aspect ratio leads to a reduction in both pick-out and film thickness for a given land width and groove cross-sectional shape. [Copyright &y& Elsevier]

Abstract: Tri-helical, gravure roll coating, operated in reverse mode, is investigated via a complementary experimental and theoretical approach. Flow visualisation reveals the underlying flow structure within the roll-to-web transfer region and highlights when loss of stability, that is a propensity to streaking, occurs. The latter is found to be influenced in turn by the depth of the tri-helical grooves and the capillary number. Experiments show that as the web-to-roll speed ratio is increased, so too is fluid pick-out from the grooves, although the coated film thickness may decrease. Extensive data are provided for coated film thickness, pick-out and meniscus location as a function of speed ratio, for different operating parameters. A key feature of the present investigation is the formulation of a novel complementary mathematical model for the process. The base flow within the grooves is modelled as a Poisson equation in conjunction with simplified approximations for the attendant free-surface boundary conditions. The resultant equation set is written in terms of finite Fourier sine transforms and unique solutions obtained by varying the flux until a consistent pressure distribution throughout the coating bead is obtained. Results from the model are found to be in generally good agreement with their experimental counter-parts, and are seen to predict and capture all the major features of the process over the operating range explored. [Copyright &y& Elsevier]

An experimental investigation of direct gravure coating, focusing on roll-to-web fluid transfer over a wide range of conditions is presented. The results highlight that the pickout of fluid from the gravure cells (i.e. the fraction of the cell volume transferred to the web) is affected significantly by the ratio of the web-to-roll speed, the fluid properties and the shape and size of the gravure cells. The stability of the operability window is also explored. At high web-to-roll speed ratios the pickout from the gravure cells approaches one and an instability, caused by starvation, results in streaking on the web. [Copyright &y& Elsevier]

With contemporary cystic fibrosis (CF) care, a lung abscess is an uncommon occurrence. We describe a case of a staphylococcal lung abscess in a teenage girl with CF who presented with a two-week history of non-specific malaise followed by two days of left posterior chest pain and fever. A chest radiograph was consistent with a left sided pulmonary abscess, which was confirmed on a CT scan of the chest. The abscess was drained under ultrasound guidance and cultured methicillin-sensitive Staphylococcus aureus. The patient responded well to antibiotic treatment with the abscess cavity showing complete radiological resolution by six weeks post drainage. [ABSTRACT FROM AUTHOR]

The importance of accounting for the temperature dependence of air properties in numerical simulations of air flows over pinned heat sinks is demonstrated by comparisons with recently published experiments. Numerical simulations, based on a conjugate heat transfer analysis, using the RANS-based modified k-ω turbulence model, with temperature-dependent air properties, are shown to be in significantly better agreement with experimental measurements of pressure drop, heat transfer coefficient, and heat sink base temperature, than those which employ constant air properties. [ABSTRACT FROM AUTHOR]

Abstract: Results from a systematic experimental investigation of deformable roll coating, operating in forward mode, are presented, with particular emphasis as to how the governing parameters of the coater (peripheral roll speed and gap setting) and the physical properties of the associated deformable roll covering (thickness, hardness and material type) influence the onset of the ribbing instability. It is found that for positive gap settings, the critical roll speed at which ribs are first observed can be increased by employing a larger gap or using a thicker covering of compliant material. For negative gap settings, explored here for the first time, ribbing is observed to be ever present over the operating range considered. However, for large negative gaps, a reduction in roll speed and the use of a thinner compliant covering are all found to produce ribs of shorter wavelength. [Copyright &y& Elsevier]

Abstract: Real-time fluid simulation is an active field of research in computer graphics, but they usually focus on visual impact rather than physical accuracy. However, by combining a lattice Boltzmann model with the parallel computing power of a graphics processing unit, both real-time compute capability and satisfactory physical accuracy are now achievable. The implementation of an optimized 3D real-time thermal and turbulent fluid flow solver with a performance of half a billion lattice node updates per second is described in detail. The effects of the hardware error checking code and the competition between appropriate boundary conditions and performance capabilities are discussed. [Copyright &y& Elsevier]

The impact of mechanical left ventricular (LV) unloading before reperfusion on myocardial energetics in acute myocardial infarction (AMI) is unknown. We hypothesized that LV unloading reduces anaerobic glycolysis in models of ischemia reperfusion injury (IRI). Myocardial ischemia was induced by percutaneous occlusion of the left anterior descending (LAD) artery for 90 minutes in adult swine. In Groups A and B, an additional 120 minutes of LAD occlusion was performed in the presence or absence of a trans-valvular pump (TVP). In Group C and D, post ischemia or LV unloading was followed by 120 minutes of reperfusion (Fig. 1A). Tissue from the infarct and non-infarct zones was analyzed using Ultrahigh Performance Liquid Chromatography-Tandem Mass Spectroscopy. In Groups A/B, LV unloading without reperfusion reduced lactate by 30±4% (p<0.006), glucose by 25±5% (p<0.02), and intermediates of glucose metabolism and ATP production consistent with decreased anaerobic glycolysis and reduced myocardial oxygen demand (Fig. 1B-C). In Groups C/D, LV unloading before reperfusion increased lactate and glucose levels by 30±5% and 75±30%, respectively (p<0.05), and increased intermediates of glucose oxidation and the tricarboxylic acid cycle. We report for the first time that LV unloading during coronary occlusion reduces anaerobic glycolysis, energy substrate utilization and ATP production. These data support the need for further studies exploring the utility of LV unloading in AMI. [ABSTRACT FROM AUTHOR]

Use of acute mechanical circulatory support (AMCS) for cardiogenic shock (CS) is growing. We sought to determine whether plasma protein profiles are differentially regulated after initiation of veno-arterial extracorporeal membrane oxygenation (ECMO) or Impella in patients with CS. Plasma samples were collected before device implantation and 72 hours after initiation of support in 11 CS patients receiving ECMO (n=5) or Impella (n=6). The aptamer-based SOMAscan assay was used to detect 1305 circulating proteins. Ingenuity Pathway Analysis identified cellular pathways and network interactions defined by proteins with a fold change >1.3 or <0.7 and p<0.05 after AMCS initiation. 67/1305 proteins were changed after ECMO (18 upregulated and 49 downregulated, p<0.05) and 38/1305 after Impella (10 upregulated and 28 downregulated, p<0.05). Only 8 proteins were commonly affected by ECMO and Impella. Despite minimal overlap in individual proteins, both devices were associated with markers of reduced inflammation including regulatory cytokines and increased apoptosis of leukocytes, phagocytes, and antigen-presenting cells (Figures A-B). Using unbiased proteomic screening we identified that ECMO and Impella are associated with reduced expression of inflammatory markers and increased markers of inflammatory cell death. These circulating proteins may serve as novel targets of therapy or novel biomarkers to tailor AMCS device use and improve patient outcomes. [ABSTRACT FROM AUTHOR]

Background: Concern exists that involving vulnerable individuals as participants in research into suicide and self-harm may cause distress and increase suicidal feelings. Actual understanding of participants' experiences is however limited, especially in relation to in-depth qualitative research.Methods: Data were collected from four separate studies focused on self-harm or suicide. These included people with varying levels of past distress, including some who had made nearly lethal suicide attempts. Each involved semi-structured qualitative interviewing. Participants (n=63) were asked to complete a visual analogue scale measuring current emotional state before and after their interview and then comment on how they had experienced the interview, reflecting on any score change.Results: Most participants experienced a change in well-being. Between 50% and 70% across studies reported improvement, many describing the cathartic value of talking. A much smaller group in each study (18-27%) reported lowering of mood as they were reminded of difficult times or forced to focus on current issues. However, most anticipated that their distress would be transient and it was outweighed by a desire to contribute to research. An increase in distress did not therefore necessarily indicate a negative experience.Limitations: There was no follow-up so the long-term effects of participation are unknown. Scores and post interview reflections were collected from participants by the researcher who had conducted the interview, which may have inhibited reporting of negative effects.Conclusions: These findings suggest individuals are more likely to derive benefit from participation than experience harm. Overprotective gate-keeping could prevent some individuals from gaining these benefits. [ABSTRACT FROM AUTHOR]

Abstract: Transient Epileptic Amnesia (TEA) is a form of temporal lobe epilepsy associated with ictal and interictal memory disturbance. Some patients with TEA exhibit Accelerated Long-term Forgetting (ALF), in which memory for verbal and non-verbal material is retained normally over short delays but fades at an unusually rapid rate over days to weeks. This study addresses three questions about ALF in TEA: (i) whether real-life events undergo ALF in a similar fashion to laboratory-based stimuli; (ii) whether ALF can be detected within 24h; (iii) whether procedural memories are susceptible to ALF. Eleven patients with TEA and eleven matched healthy controls wore a novel, automatic camera, SenseCam, while visiting a local attraction. Memory for images of events was assessed on the same day and after delays of one day, one week, and three weeks. Forgetting of real-life events was compared with forgetting of a word list and with performance on a procedural memory task. On the day of their excursion, patients and controls recalled similar numbers of primary events, associated secondary details (contiguous events, thoughts and sensory information) and items from the word list. In contrast, patients showed ALF for primary events over three weeks, with ALF for contiguous events, thoughts and words over the first day. Retention on the procedural memory task was normal over three weeks. The results indicate that accelerated forgetting in TEA: (i) affects memory for real-life events as well as laboratory stimuli; (ii) is maximal over the first day; and (iii) is specific to declarative memories. [ABSTRACT FROM AUTHOR]

Mortality in cardiogenic shock (CS) remains prohibitively high despite recent advances in treatment. The extent of clinical benefit of the use of pulmonary artery catheters (PACs) in CS patients is still unclear. We hypothesize that the comprehensive assessment of PAC data is associated with reduced risk of in-hospital mortality in CS patients. 1,414 all-cause CS patients from the Cardiogenic Shock Working Group Registry, a national multicenter retrospective CS registry, were classified according to the Society for Cardiovascular Angiography and Intervention (SCAI) CS stages and evaluated for PAC use. PAC use was quantified by the presence of pulmonary artery saturation, pulmonary artery pressures and wedge pressure. We compared patients without any of these measurements (No PAC data), patients with at least one (Some PAC data) and patients with all these parameters and right atrial pressure (Complete PAC data). PAC usage was analyzed for association with in-hospital mortality in a multivariate logistic regression model. Of the total cohort of 1414 patients, 267 (18.88%) had no recorded PAC data, 549 (38.83%) had partially recorded PAC data, and 598 (42.29%) had complete PAC data. The majority of SCAI stage B (n=43, 93.5%) and C (n=132, 50.19%) had complete PAC data while the majority of SCAI stages D (n=361, 47.63%) and E (n=90, 42.45%) had some PAC data. After adjusting for institution in the total cohort, patients with complete PAC data had almost half the risk of mortality compared to those with no PAC data (OR 95%CI: 0.586, 0.418-0.822) and those with partial PAC data (OR 95%CI: 0.602, 0.467-0.813). The differences in mortality by PAC usage in the overall and SCAI stage cohorts are summarized in the figure below. These data suggest that using a PAC in CS patients, especially those in more critical condition, may decrease their risk of in-hospital mortality. This benefit could potentially be explained by the information provided by the PAC in developing a more appropriate treatment plan. [ABSTRACT FROM AUTHOR]

Cardiogenic shock (CS) mortality remains unacceptably high. Risk stratification of CS patients may improve trial design and treatment strategies. We tested the application of the expert consensus-based Society for Cardiovascular Angiography and Intervention (SCAI) CS stages in a retrospective dataset. Furthermore, we hypothesized that unsupervised clustering of CS patients is feasible and identifies clinically applicable phenotypes of CS. The Cardiogenic Shock Working Group (CSWG) registry is a retrospective multicenter registry of patients with all-cause CS. Descriptive analyses were performed on 1,414 CSWG patients to quantify the association of clinical variables and in-hospital mortality. In myocardial infarction-caused CS (AMICS) patients, a random forest classifier was used to identify variables that predict in-hospital mortality in CSWG. Consensus k means clustering was performed on these variables in 1,000 randomly assigned 85% samples of 408 AMICS patients from the CSWG training cohort and 701 AMICS patients from the Danish National Patient Registry (DNPR). CSWG patients with heart failure (CSWG-HF, n=480) were then assigned to the clusters. Variables associated with in-hospital mortality in all-cause CS included SCAI Stages, but also pulmonary artery catheter use, and venous congestion. In AMICS the mortality driving continuous variables comprised glomerular filtration rate, lactate, HCO3, platelets, alanine aminotransferase, and white blood cell count. Independent, unsupervised consensus k means clustering on these variables identified three phenotypes of CS that were associated with in-hospital mortality in similar patterns in CSWG, DNPR, and CSWG-HF. The phenotypes revealed unique demographic, clinical, metabolic and hemodynamic profiles. This is the first report to employ an unbiased, machine learning approach in CS and identified 3 phenotypes of patients with CS due to MI. These findings may inform treatment strategies and future CS clinical trials. [ABSTRACT FROM AUTHOR]

Impella percutaneous left ventricular assist devices (LVAD) (Abiomed, Danvers, MA) use is rapidly expanding for cardiogenic shock management. Devices are delivered through the aortic valve (AV). Due to the design, there remains concern that Impella may disrupt aortic valve morphology and competency, potentially causing secondary aortic insufficiency (AI) after explantation. Secondary AI could compromise cardiac function and may further reduce the efficacy of future mechanical circulatory support. Prior reports are limited and results remain unclear. The aim of this study is to characterize the relationship between Impella placement and AI after explantation. This was a single center retrospective analysis. All patients who had Impella LVAD support from April 2014 to August 2019 were included. Patient demographics, implant indications, duration of support, and pre- and post-implant echocardiograms were analyzed. Post-implant echocardiograms were analyzed at eight time points, with focus on the most recent finding. ASE guidelines were used to quantify AI. Impella CP and Impella 5.0 patients were sub-analyzed separately. A Mann Whitney U-test was performed on AI analysis. Any AV complications requiring surgical procedures were reviewed. 146 patients received Impella (CP: n= 104, 71.2%, 5.0: n=37, 25.3%, 2.5: n=5, 3.4%) support. Mean age was 63.8 years (16-88). 27.4% of patients were female (n=40). Mean days of support was 4.8 days (0-28). Mean follow up time was 70.2 days post-implant (0-1484 days). Indications were bridge to recovery, bridge to LVAD or heart transplant, ECPELLA, and high-risk PCI, respectively (n=57, 39.0%; n=19, 13.0%; n=18, 12.3%; n=52, 35.6%). The pre-implant and post-explant degree of AI is shown in figure 1. There was no statistically significant AI progression (p=0.76). One patient developed severe AI and required an AV replacement (0.68%). Although increasing AI post-Impella support is rare, careful follow up is warranted. [ABSTRACT FROM AUTHOR]