Electrochemical versus gas-phase oxidation of ru single-crystal surfaces

The electrochemical uptake of oxygen on a Ru(0001) electrode was investigated by electron diffraction, Auger spectroscopy, and cyclic voltammetry. An ordered (2 × 2)-O overlayer forms at a potential close to the hydrogen region. At +0.42 and +1.12 V vs Ag/AgCl, a (3 × 1) phase and a (1 × 1)-O phase, respectively, emerge. When the Ru electrode potential is maintained at +1.12 V for 2 min, RuO2 grows epitaxially with its (100) plane parallel to the Ru(0001) surface. In contrast to the RuO domains, the non-oxidized regions of the Ru electrode surface are flat. If, however, the electrode potential is increased to +1.98 V for 2 min, the remaining non-oxidized Ru area also becomes rough. These findings are compared with O overlayers and oxides on the Ru(0001) and Ru(101¯1) surfaces created by exposure to gaseous O under UHV conditions. On the other hand, gas-phase oxidation of the Ru(101¯0) surface leads to the formation of RuO with a (100) orientation. It is concluded that the difference in surface energy between RuO(110) and RuO(100) is quite small. RuO again grows epitaxially on Ru(0001), but with the (110) face oriented parallel to the Ru(0001) surface. The electrochemical oxidation of the Ru(0001) electrode surface proceeds via a 3-dimensional growth mechanism with a mean cluster size of 1.6 nm, whereas under UHV conditions, a 2-dimensional oxide film (1-2 nm thick) is epitaxially formed with an average domain size of 20 µm. © 2000 American Chemical Society.

Disordered vascular compliance in haemochromatosis

Background: A relationship may exist between body iron stores, endothelial dysfunction and overall cardiovascular risk.

Aims: To compare vascular compliance, biochemical endothelial function and antioxidant status between patients with homozygous hereditary haemochromatosis and healthy controls.

Methods: Haemochromatosis patients and healthy controls were recruited. Measures of vascular compliance were assessed by applanation tonometry. Serological markers of endothelial function (plasma lipid hydroperoxides, cell adhesion molecules), antioxidant levels (ascorbate, lipid soluble antioxidants) and high-sensitivity C-reactive protein (CRP) were also measured.

Results: Thirty-five hereditary haemochromatosis patients (ten females, mean age 54.6) and 36 controls (27 female, mean age 54.0) were recruited. Haemochromatosis patients had significantly higher systolic and diastolic blood pressures. Pulse wave velocity (PWV) was significantly higher in male haemochromatosis patients (9.90 vs. 8.65 m/s, p = 0.048). Following adjustment for age and blood pressure, male haemochromatosis patients continued to have a trend for higher PWVs (+1.37 m/s, p = 0.058). Haemochromatosis patients had significantly lower levels of ascorbate (46.11 vs. 72.68 lmol/L, p = 0.011), retinol (1.17 vs. 1.81 lmol/L, p = 0.001) and g-tocopherol (2.51 vs. 3.14 lmol/L, p = 0.011). However, there was no difference in lipid hydroperoxides (0.46 vs. 0.47 nmol/L, p = 0.94), cell adhesion molecule levels (ICAM: 348.12 vs. 308.03 ng/mL, p = 0.32 and VCAM: 472.78 vs. 461.31 ng/mL, p = 0.79) or high-sensitivity CRP (225.01 vs. 207.13 mg/L, p = 0.32).

Conclusions: Haemochromatosis is associated with higher PWVs in males and diminished antioxidants across the sexes but no evidence of endothelial dysfunction or increased lipid peroxidation.

Prospective clinical audit of chloral hydrate administration practices in a neonatal unit

Aim: Chloral hydrate is generally considered a safe and effective single dosing procedural sedative for neonates in the clinical setting. However, its safety profile as a repetitive dosing maintenance sedative is largely unknown. This study aimed to document current administration practices of chloral hydrate in the Neonatal Unit, Royal Children's Hospital, Melbourne, Australia, over a 6-month period.

Methods: Patients who had been prescribed chloral hydrate during the specified audit period were recruited into the study and prospectively followed for a period of 28 days, or until they were discharged from the unit. Demographic data were collected on recruitment, and daily documentation of chloral hydrate administration was recorded.

Results: A total of 238 doses of chloral hydrate were administered to a cohort of 32 patients during the study period. The majority of the audited doses (84%) were ordered as repeating doses. Doses were more likely to be given at night than during the day, and the median dosage for repetitive dosing was found to be above the study site's recommended dosing range. Pre-dose and/or post-dose assessment of distress/agitation accompanied dosage approximately half of the time. The audit did not reveal any recognisable pattern of sedation maintenance or weaning process for patients who received multiple doses.

Conclusions: Health-care professionals caring for hospitalised infants should be made aware of the potential risks of chloral hydrate as a repetitive dosing sedative, and of the importance of systematically evaluating the appropriateness and effectiveness of utilising such pharmacological intervention for managing and treating distress.

Let's talk about health: shoppers' discourse regarding health while food shopping

Objective: The present study aimed to examine the role of health in consumers’ food purchasing decisions through investigating the nature of people’s discourse regarding health while conducting their food shopping.

Design: The study employed the think-aloud technique as part of an accompanied shop. All mentions of health and terms relating to health were identified from the data set. Inductive thematic analysis was conducted to examine how health was talked about in relation to people’s food choice decisions.

Setting: Supermarkets in Dublin, Republic of Ireland and Belfast, Northern Ireland.

Subjects Participants: (n 50) were aged over 18 years and represented the main household shopper.

Results: Responsibility for others and the perceived need to illicit strict control to avoid ‘unhealthy’ food selections played a dominant role in how health was talked about during the accompanied shop. Consequently healthy shopping was viewed as difficult and effort was required to make the healthy choice, with shoppers relating to product-based inferences to support their decisions.

Conclusions: This qualitative exploration has provided evidence of a number of factors influencing the consideration of health during consumers’ food shopping. These results highlight opportunities for stakeholders such as public health bodies and the food industry to explore further ways to help enable consumers make healthy food choices.

Human mesenchymal stem cells reduce the severity of acute lung injury in a sheep model of bacterial pneumonia

Background Human bone marrow-derived mesenchymal stem (stromal) cells (hMSCs) improve survival in mouse models of acute respiratory distress syndrome (ARDS) and reduce pulmonary oedema in a perfused human lung preparation injured with Escherichia coli bacteria. We hypothesised that clinical grade hMSCs would reduce the severity of acute lung injury (ALI) and would be safe in a sheep model of ARDS.

Methods Adult sheep (30–40 kg) were surgically prepared. After 5 days of recovery, ALI was induced with cotton smoke insufflation, followed by instillation of live Pseudomonas aeruginosa (2.5×10¹¹ CFU) into both lungs under isoflurane anaesthesia. Following the injury, sheep were ventilated, resuscitated with lactated Ringer's solution and studied for 24 h. The sheep were randomly allocated to receive one of the following treatments intravenously over 1 h in one of the following groups: (1) control, PlasmaLyte A, n=8; (2) lower dose hMSCs, 5×10⁶ hMSCs/kg, n=7; and (3) higher-dose hMSCs, 10×10⁶ hMSCs/kg, n=4.

Results By 24 h, the PaO₂/FiO₂ ratio was significantly improved in both hMSC treatment groups compared with the control group (control group: PaO₂/FiO₂ of 97±15 mm Hg; lower dose: 288±55 mm Hg (p=0.003); higher dose: 327±2 mm Hg (p=0.003)). The median lung water content was lower in the higher-dose hMSC-treated group compared with the control group (higher dose: 5.0 g wet/g dry [IQR 4.9–5.8] vs control: 6.7 g wet/g dry [IQR 6.4–7.5] (p=0.01)). The hMSCs had no adverse effects.

Conclusions Human MSCs were well tolerated and improved oxygenation and decreased pulmonary oedema in a sheep model of severe ARDS.

Developing an international Pseudomonas aeruginosa reference panel

Pseudomonas aeruginosa is a major opportunistic pathogen in cystic fibrosis (CF) patients and causes a wide range of infections among other susceptible populations. Its inherent resistance to many antimicrobials also makes it difficult to treat infections with this pathogen. Recent evidence has highlighted the diversity of this species, yet despite this, the majority of studies on virulence and pathogenesis focus on a small number of strains. There is a pressing need for a P. aeruginosa reference panel to harmonize and coordinate the collective efforts of the P. aeruginosa research community. We have collated a panel of 43 P. aeruginosa strains that reflects the organism's diversity. In addition to the commonly studied clones, this panel includes transmissible strains, sequential CF isolates, strains with specific virulence characteristics, and strains that represent serotype, genotype or geographic diversity. This focussed panel of P. aeruginosa isolates will help accelerate and consolidate the discovery of virulence determinants, improve our understanding of the pathogenesis of infections caused by this pathogen, and provide the community with a valuable resource for the testing of novel therapeutic agents.

Evaluating environmental enrichment options for commercial broiler chickens

Implications Provision of environmental enrichment in line with that required by welfare-based quality assurance schemesdoes not always appear to lead to clear improvements in broiler chicken welfare. This research perhaps serves to highlightthe deficit in information regarding the ‘real world’ implications of enrichment with perches, string and straw bales.

Introduction Earlier work showed that provision of natural light and straw bales improved leg health in commercial broilerchickens (Bailie et al., 2013). This research aimed to determine if additional welfare benefits were shown in windowedhouses by increasing straw bale provision (Study 1), or by providing perches and string in addition to straw bales (Study 2).

Material and methods Commercial windowed houses in Northern Ireland containing ~23,000 broiler chickens (placed inhouses as hatched) were used in this research which took place in 2011. In Study 1 two houses on a single farm wereassigned to one of two treatments: (1) 30 straw bales per house (1 bale/44m2), or (2) 45 straw bales per house (1bale/29m2). Bales of wheat straw, each measuring 80cm x 40cm x 40cm were provided from day 10 of the rearing cycle,as in Bailie et al. (2013). Treatments were replicated over 6 production cycles (using 276,000 Ross 308 and Cobb birds),and were swapped between houses in each replicate. In Study 2, four houses on a single farm were assigned to 1 of 4treatments in a 2 x 2 factorial design. Treatments involved 2 levels of access to perches (present (24/house), or absent), and2 levels of access to string (present (24/house), or absent), and both types of enrichment were provided from the start of thecycle. Each perch consisted of a horizontal, wooden beam (300 cm x 5 cm x 5cm) with a rounded upper edge resting on 2supports (15 cm high). In the string treatment, 6 pieces of white nylon string (60 cm x 10 mm) were tied at their mid-pointto the wire above each of 4 feeder lines. Thirty straw bales were also provided per house from day 10. This study wasreplicated over 4 production cycles using 368,000 Ross 308 birds. In both studies behaviour was observed between 0900and 1800 hours in weeks 3-5 of the cycle. In Study 1, 8 focal birds were selected in each house each week, and generalactivity, exploratory and social behaviours recorded directly for 10 minutes. In Study 2, 10 minute video recordings weremade of 6 different areas (that did not contain enrichment) of each house each week. The percentage of birds engaged inlocomotion or standing was determined through scan sampling these recordings at 120 second intervals. Four perches andfour pieces of string were filmed for 25 mins in each house that contained these enrichments on one day per week. The totalnumber of times the perch or string was used was recorded, along with the duration of each bout. In both studies, gaitscores (0 (perfect) to 5 (unable to walk)) and latency to lie (measured in seconds from when a bird had been encouraged tostand) were recorded in 25 birds in each house each week. Farm and abattoir records were also used in both studies todetermine the number of birds culled for leg and other problems, mortality levels, slaughter weights, and levels of pododermatitis and hock burn. Data were analysed using SPSS (version 20.0) and treatment and age effects on behaviouralparameters were determined in normally distributed data using ANOVA (‘Straw bale density*week’, or‘string*perches*week’ as appropriate), and in non-normally distributed data using Kuskall-Wallace tests (P<0.05 forsignificance) . Treatment (but not age) effects on performance and health data were determined using the same testsdepending on normality of data.

Results Average slaughter weight, and levels of mortality, culling, hock burn and pododermatitis were not affected bytreatment in either study (P<0.05). In Study 1 straw bale (SB) density had no significant effect on the frequency orduration of behaviours including standing, walking, ground pecking, dust bathing, pecking at bales or aggression, or onaverage gait score (P>0.05). However, the average latency to lie was greater when fewer SB were provided (30SB 23.38s,45SB 18.62s, P<0.01). In Study 2 there was an interaction between perches (Pe) and age in lying behaviour, with higherpercentages of birds observed lying in the Pe treatment during weeks 4 and 5 (week 3 +Pe 77.0 -Pe 80.9, week 4 +Pe 79.5 -Pe 75.2, week 5 +Pe 78.4 -Pe 76.2, P<0.02). There was also a significant interaction between string (S) and age inlocomotory behaviour, with higher percentages of birds observed in locomotion in the string treatment during week 3 butnot weeks 4 and 5 (week 3 +S 4.9 -S 3.9, week 4 +S 3.3 -S 3.7, week 5 +S 2.6 -S 2.8, P<0.04). There was also aninteraction between S and age in average gait scores, with lower gait scores in the string treatment in weeks 3 and 5 (week3: +S 0.7, -S 0.9, week 4: +S 1.5, -S 1.4, week 5: +S 1.9, -S 2.0, P<0.05). On average per 25 min observation there were15.1 (±13.6) bouts of perching and 19.2 (±14.08) bouts of string pecking, lasting 117.4 (±92.7) and 4.2 (±2.0) s for perchesand string, respectively.

Conclusion Increasing straw bale levels from 1 bale/44m2 to 1 bale/29m2 floor space does not appear to lead to significantimprovements in the welfare of broilers in windowed houses. The frequent use of perches and string suggests that thesestimuli have the potential to improve welfare. Provision of string also appeared to positively influence walking ability.However, this effect was numerically small, was only shown in certain weeks and was not reflected in the latency to lie.Further research on optimum design and level of provision of enrichment items for broiler chickens is warranted. Thisshould include measures of overall levels of activity (both in the vicinity of, and away from, enrichment items).

FRENKEL-KONTOROVA DOMAIN-WALL PHASE-TRANSITIONS IN AN ADSORBED LAYER - POTASSIUM ON CO(10(1)OVER-BAR-0)

As the potassium fractional coverage of a cobalt {1010BAR} surface is increased over the range 0.2 to 0.6 monolayer the adlayer passes through a series of phase transitions. A commensurate phase is formed at exactly 0.5 monolayer, and corresponds to adatoms bonded in high-symmetry hollow sites on the unreconstructed cobalt surface, with an effective adatom radius lying between the ionic and covalent radii of potassium. A detailed structural study shows that the structural transitions can be characterised within a one-dimensional Frenkel-Kontorova model, with small lateral displacements of adatoms away from hollow sites in the low and high coverage phases. The low coverage phases progress from a distributed vacancy structure to a low density domain-wall structure; while the high coverage phase formed above half a monolayer is a high density asymmetric domain-wall structure.

PS1-10afx at z = 1.388: Pan-STARRS1 Discovery of a New Type of Superluminous Supernova

We present the Pan-STARRS1 discovery of PS1-10afx, a unique hydrogen-deficient superluminous supernova (SLSN) at redshift z = 1.388. The light curve peaked at z P1 = 21.7 mag, making PS1-10afx comparable to the most luminous known SNe, with Mu = -22.3 mag. Our extensive optical and near-infrared observations indicate that the bolometric light curve of PS1-10afx rose on the unusually fast timescale of ~12 days to the extraordinary peak luminosity of 4.1 × 1044 erg s-1 (M bol = -22.8 mag) and subsequently faded rapidly. Equally important, the spectral energy distribution is unusually red for an SLSN, with a color temperature of ~6800 K near maximum light, in contrast to previous hydrogen-poor SLSNe, which are bright in the ultraviolet (UV). The spectra more closely resemble those of a normal SN Ic than any known SLSN, with a photospheric velocity of ~11, 000 km s-1 and evidence for line blanketing in the rest-frame UV. Despite the fast rise, these parameters imply a very large emitting radius (gsim 5 × 1015 cm). We demonstrate that no existing theoretical model can satisfactorily explain this combination of properties: (1) a nickel-powered light curve cannot match the combination of high peak luminosity with the fast timescale; (2) models powered by the spindown energy of a rapidly rotating magnetar predict significantly hotter and faster ejecta; and (3) models invoking shock breakout through a dense circumstellar medium cannot explain the observed spectra or color evolution. The host galaxy is well detected in pre-explosion imaging with a luminosity near L*, a star formation rate of ~15 M ⊙ yr-1, and is fairly massive (~2 × 1010 M ⊙), with a stellar population age of ~108 yr, also in contrast to the young dwarf hosts of known hydrogen-poor SLSNe. PS1-10afx is distinct from known examples of SLSNe in its spectra, colors, light-curve shape, and host galaxy properties, suggesting that it resulted from a different channel than other hydrogen-poor SLSNe.

Global surveillance of cancer survival 1995–2009: analysis of individual data for 25 676 887 patients from 279 population-based registries in 67 countries (CONCORD-2)

BACKGROUND: Worldwide data for cancer survival are scarce. We aimed to initiate worldwide surveillance of cancer survival by central analysis of population-based registry data, as a metric of the effectiveness of health systems, and to inform global policy on cancer control.

METHODS: Individual tumour records were submitted by 279 population-based cancer registries in 67 countries for 25·7 million adults (age 15-99 years) and 75,000 children (age 0-14 years) diagnosed with cancer during 1995-2009 and followed up to Dec 31, 2009, or later. We looked at cancers of the stomach, colon, rectum, liver, lung, breast (women), cervix, ovary, and prostate in adults, and adult and childhood leukaemia. Standardised quality control procedures were applied; errors were corrected by the registry concerned. We estimated 5-year net survival, adjusted for background mortality in every country or region by age (single year), sex, and calendar year, and by race or ethnic origin in some countries. Estimates were age-standardised with the International Cancer Survival Standard weights.

FINDINGS: 5-year survival from colon, rectal, and breast cancers has increased steadily in most developed countries. For patients diagnosed during 2005-09, survival for colon and rectal cancer reached 60% or more in 22 countries around the world; for breast cancer, 5-year survival rose to 85% or higher in 17 countries worldwide. Liver and lung cancer remain lethal in all nations: for both cancers, 5-year survival is below 20% everywhere in Europe, in the range 15-19% in North America, and as low as 7-9% in Mongolia and Thailand. Striking rises in 5-year survival from prostate cancer have occurred in many countries: survival rose by 10-20% between 1995-99 and 2005-09 in 22 countries in South America, Asia, and Europe, but survival still varies widely around the world, from less than 60% in Bulgaria and Thailand to 95% or more in Brazil, Puerto Rico, and the USA. For cervical cancer, national estimates of 5-year survival range from less than 50% to more than 70%; regional variations are much wider, and improvements between 1995-99 and 2005-09 have generally been slight. For women diagnosed with ovarian cancer in 2005-09, 5-year survival was 40% or higher only in Ecuador, the USA, and 17 countries in Asia and Europe. 5-year survival for stomach cancer in 2005-09 was high (54-58%) in Japan and South Korea, compared with less than 40% in other countries. By contrast, 5-year survival from adult leukaemia in Japan and South Korea (18-23%) is lower than in most other countries. 5-year survival from childhood acute lymphoblastic leukaemia is less than 60% in several countries, but as high as 90% in Canada and four European countries, which suggests major deficiencies in the management of a largely curable disease.

INTERPRETATION: International comparison of survival trends reveals very wide differences that are likely to be attributable to differences in access to early diagnosis and optimum treatment. Continuous worldwide surveillance of cancer survival should become an indispensable source of information for cancer patients and researchers and a stimulus for politicians to improve health policy and health-care systems.

Elucidating the mechanism and active site of the cyclohexanol dehydrogenation on copper-based catalysts: A density functional theory study

Abstract The dehydrogenation of cyclohexanol to cyclohexanone is very important in the manufacture of nylon. Copper-based catalysts are the most popular catalysts for this reaction, and on these catalysts the reaction mechanism and active site are in debate. In order to elucidate the mechanism and active site of the cyclohexanol dehydrogenation on copper-based catalysts, density functional theory with dispersion corrections were performed on up to six facets of copper in two different oxidation states: monovalent copper and metallic copper. By calculating the surface energies of these facets, Cu(111) and Cu2O(111) were found to be the most stable facets for metallic copper and for monovalent copper, respectively. On these two facets, all the possible elementary steps in the dehydrogenation pathway of cyclohexanol were calculated, including the adsorption, dehydrogenation, hydrogen coupling and desorption. Two different reaction pathways for dehydrogenation were considered on both surfaces. It was revealed that the dehydrogenation mechanisms are different on these two surfaces: on Cu(111) the hydrogen belonging to the hydroxyl is removed first, then the hydrogen belonging to the carbon is subtracted, while on Cu2O(111) the hydrogen belonging to the carbon is removed followed by the subtraction of the hydrogen in the hydroxyl group. Furthermore, by comparing the energy profiles of these two surfaces, Cu2O(111) was found to be more active for cyclohexanol dehydrogenation than Cu(111). In addition, we found that the coordinatively unsaturated copper sites on Cu2O(111) are the reaction sites for all the steps. Therefore, the coordinatively unsaturated copper site on Cu2O(111) is likely to be the active site for cyclohexanol dehydrogenation on the copper-based catalysts.

X-Ray Emission from the Super-Earth Host GJ 1214

Stellar activity can produce large amounts of high-energy radiation, which is absorbed by the planetary atmosphere leading to irradiation-driven mass loss. We present the detection and an investigation of high-energy emission in a transiting super-Earth host system, GJ 1214, based on XMM-Newton observations. We derive an X-ray luminosity of LX = 7.4 × 1025 erg s-1 and a corresponding activity level of log (LX /L bol) ~ -5.3. Further, we determine a coronal temperature of about ~3.5 MK, which is typical for coronal emission of moderately active low-mass stars. We estimate that GJ 1214 b evaporates at a rate of 1.3× 1010 g s-1 and has lost a total of ≈2-5.6 M ⊕.

Indexing and matching trajectories under inconsistent sampling rates

Quantifying the similarity between two trajectories is a fundamental operation in analysis of spatio-temporal databases. While a number of distance functions exist, the recent shift in the dynamics of the trajectory generation procedure violates one of their core assumptions; a consistent and uniform sampling rate. In this paper, we formulate a robust distance function called Edit Distance with Projections (EDwP) to match trajectories under inconsistent and variable sampling rates through dynamic interpolation. This is achieved by deploying the idea of projections that goes beyond matching only the sampled points while aligning trajectories. To enable efficient trajectory retrievals using EDwP, we design an index structure called TrajTree. TrajTree derives its pruning power by employing the unique combination of bounding boxes with Lipschitz embedding. Extensive experiments on real trajectory databases demonstrate EDwP to be up to 5 times more accurate than the state-of-the-art distance functions. Additionally, TrajTree increases the efficiency of trajectory retrievals by up to an order of magnitude over existing techniques.