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In this study, as a measure to enhance the antimicrobial activity of biomaterials, the selenium ions have been substituted into hydroxyapatite (HA) at different concentration levels. To balance the potential cytotoxic effects of selenite ions (SeO32−) in HA, strontium (Sr2+) was co-substituted at the same concentration. Selenium and strontium-substituted hydroxyapatites (Se-Sr-HA) at equal molar ratios of x Se/(Se + P) and x Sr/(Sr + Ca) at (x = 0, 0.01, 0.03, 0.05, 0.1, and 0.2) were synthesized via the wet precipitation route and sintered at 900 °C. The effect of the two-ion concentration on morphology, surface charge, composition, antibacterial ability, and cell viability were studied. X-ray diffraction verified the phase purity and confirmed the substitution of selenium and strontium ions. Acellular in vitro bioactivity tests revealed that Se-Sr-HA was highly bioactive compared to pure HA. Se-Sr-HA samples showed excellent antibacterial activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus carnosus) bacterial strains. In vitro cell–material interaction, using human osteosarcoma cells MG-63 studied by WST-8 assay, showed that Se-HA has a cytotoxic effect, however, the co-substitution of strontium in Se-HA offsets the negative impact of selenium and enhanced the biological properties of HA. Hence, the prepared samples are a suitable choice for antibacterial coatings and bone filler applications.

Objectives To assess in vitro the effect of experimental mesoporous BAG, on human dental pulp cells (hDPCs) behavior in terms of cytocompatiblity and bioactivity via mineralization potential. Methods Fine (FP) and large particles (LP) of a fixed BAG composition named 0NaMBG have been elaborated by a sol-gel process. In vitro assessment was achieved on cultured primary hDPCs using indirect contact. The effect of the concentration of 800 μg/mL on cell metabolic activity and cytotoxicity were examined by performing Alamar blue and crystal violet assays. Alizarin Red staining was used to detect and quantify the formation of mineralized nodules and ALP activity was colourimetrically quantified. The expression of Odontogenic markers: DMP-1 and osteopontin (OPN) expression and cell morphology was evaluated by confocal microscopy. Results According to the Alamar blue and crystal violet assay, 0NaMBG samples were non-cytotoxic. Cells treated with 0NaMBG particles expressed higher metabolic activity than control cells, especially for LP. Both FP and LP significantly increased both extra and intra cellular ALP activity. hDPCs exhibited good cell spreading and adhesion in the presence of FP and LP extracts by confocal imaging. Further, Alizarin red S assay demonstrated more mineralization nodules and significant enhancement of the extracellular calcium deposition when cells were interfaced with both FP and LP compared to the control cells. Moreover, LP extracts enhanced the production and secretion of odontogenic markers: dentin matrix protein 1 (DMP-1) and osteopontin. Significance LP have a higher surface area and pore volume, which could explain their greater bioactivity in contact with pulp cells. The clinical relevance of these findings implicate that 0NaMBG could be used as fillers in dental therapeutic materials suitable for dentin and/or pulp tissues preservation.

Phosphate-based glasses (PBG) have low melting temperatures and can be obtained by melt-quenching and sol-gel methods. The most significant characteristic of PBG is their ability to dissolve completely in aqueous solution within different timeframes. This solubility can reduce the need for revision surgeries and makes PBG well-suited for soft tissue regeneration. Phosphate glass fibres (PGF) due to their geometry and volume–surface area ratio are the subject of a growing number of studies on resorbable composites. Medical applications include bone fixation devices, nerve tissue scaffolds and wound healing. PBG can be doped with various ions to enhance their biological, chemical and structural properties allowing the preparation of fibres with designed properties and with the ability to release biologically active ions upon degradation. The aim of this review is to look in detail at the influence of different dopants on PGF behaviour, both at a structural and biological level.

Objective The superior textural properties of sol–gel derived bioactive glasses compared to conventional melt quench glasses accounts for their accelerated bioactivity in vitro. Several studies have explored ways to improve the surface properties of sol–gel glasses in order to maximise their efficiency for bone and tooth regeneration. In this study, we investigated the effect of order of network modifying precursor addition on the textural properties of sol–gel derived bioactive glasses. Methods The effect of precursor addition order on the glass characteristics was assessed by switching the order of network modifying precursor (calcium acetate monohydrate and sodium acetate anhydrous) addition for a fixed composition of bioactive glass (75SiO2:5CaO:10Na2O:10P2O5). Results The results of this study showed that the order of precursor addition does influence the porosity of these glasses. For the glasses of a fixed composition and preparation conditions we achieved a doubling of surface area, a 1.5 times increase in pore volume and a 1.2 times decrease in pore size just by the mixing the network modifying precursors and adding them together in the sol–gel preparation. Significance This simple and straightforward route adaptation to the preparation of bioactive glasses would allow us to enhance the textural properties of existing and novel composition of bioactive glasses and thus accelerate their bioactivity.

Sugarcane is a major economic crop that is grown mostly where water availability is a dominant limitation to production. However, selection for cane yield under dry conditions is difficult because of variable rainfall and sometimes high experimental error variance. If measurements made under relative non-stress conditions could be used to predict relative yield of genotypes under dry environments it could improve effectiveness of selection, especially in early stage selection trials in breeding programs. In this study, field experiments were conducted to evaluate 31 sugarcane genotypes in rain-fed and irrigated treatments across multiple sites and years in Yunnan province, South China. The aim was to examine relationships between cane yield and several leaf functional traits and determine if measurements made in environments experiencing low water stress could be used to predict relative yield of genotypes in dry environments. The water treatments had a large impact on mean cane yield and all the measured leaf function traits. However, for cane yield genotype × water treatment interactions were relatively small relative to genotype main effects, except when water stress was severe. For the leaf functional traits in most cases, genotype main effects were highly statistically significant while genotype × date and genotype × water interactions were mostly not statistically significant despite contrasting conditions at different dates of measurement. It was found that a combination of high yield and low leaf conductance or high leaf temperature (both of which may be related to reduced rates of water use), all measured under non-stress conditions, was predictive of yield under the limited water treatments, with prediction levels better than either yield or leaf based measurements alone. This is suggestive of a potentially valuable role for this combination of measurements in optimal selection indices in early stages of selection in sugarcane breeding programs. High sampling and error variances and high labour requirements associated with measuring conductance or leaf temperature using traditional methods are a limitation to practical application. However, these may be overcome through emerging technologies enabling related measures through aerial imaging. Development and testing of these approaches is recommended to develop better selection methods in early stage selection trials in breeding programs.

Correction for ‘Ga and Ce ion-doped phosphate glass fibres with antibacterial properties and their composite for wound healing applications’ by Agata Łapa et al., J. Mater. Chem. B, 2019, DOI: 10.1039/c9tb00820a.

Novel gallium/cerium-doped phosphate glass fibres (PGF) were successfully manufactured by the melt-quenching and melt-spinning process. The amorphous character of the materials produced was confirmed using X-ray powder diffraction (XRD), and the elemental composition was investigated with X-ray fluorescence confirming the presence of 2 mol% of Ga2O3 or CeO2. Fourier Transform Infrared Spectroscopy (FTIR) confirmed the presence of Q1 and Q2 structural phosphate species. Mechanical properties of the PGFs revealed tensile strength values of 428 ± 94 MPa and 379 ± 80 MPa, with elastic modulus values of 45 ± 4 GPa and 54 ± 9 GPa for Ce-PGF (diameter 25 μm) and Ga-PGF (diameter 18 μm), respectively. The influence of both dopants on the glass degradation properties was evaluated by tests in deionised water, which revealed a decreased dissolution rate for gallium-doped PGF in comparison to cerium-doped PGF. Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) measurements were used to explore ion release in cell culture medium, while ICP-mass spectrometry (ICP-MS) was used to measure ion release in deionised water. These techniques showed controlled release of therapeutic and antibacterial ions from the PGF. Antibacterial properties of Ce-PGF and Ga-PGF, based on turbidity measurements, were confirmed against Gram-positive bacteria. Moreover, Ce-doped phosphate glass fibres did not disturb the proliferation of human epidermal keratinocyte (HaCaT) cells or the mobility of mice embryonic fibroblasts (MEF). Applying an in vitro scratch assay showed full wound closure after 24 h of indirect incubation with Ga-PGF. Due to their superior processability as compared with Ga-PGFs, a fully degradable mesh based on Ce-PGF was designed and found to achieve high water uptake (up to 800%), suggesting its suitability for wound healing applications.

Genetic improvement of crops has been critical in reducing costs of production and improving quality and reliability of supply of food worldwide. Genetic improvement depends on testing, ranking, and selecting large numbers of candidate genotypes for predicted commercial value, based on data obtained in selection trials. However, this is often difficult because genotypes can vary for many different traits affecting costs across the value chain, including growing, harvesting, transport, processing, and sales revenue. Selection index methodology can be applied to help resolve this problem. Here we illustrate this methodology through a case study of sugarcane improvement in China. Sugarcane is a major crop, harvested and processed globally in a greater mass than any other crop, and China is the third largest producer in the world. Sugarcane industries in China and many other countries are also changing from labour intensive to mechanised systems of growing and harvesting. Accordingly, two contrasting production systems were considered: (i) current systems, including small farms and harvesting using manual labour (S1); and (ii) likely future production systems with larger farms with mechanised farming and harvesting operations and modern transport and processing sectors (S2). The economic impact of varying a range of crop traits was determined for each system, and economic weightings of each trait defined accordingly. Using example data from a selection trial in southern China, ranking of a set of sugarcane families (crosses) based on selection indices for each system was shown. Important differences in ranking of sugarcane families were observed for indices for S1 and S2, indicating how changes in selection criteria are appropriate for developing cultivars for future production systems compared with currently applied selection criteria. While the cropping production system and economic parameters in the case study were based on data from China, the approach used is applicable generally. Suggestions were made regarding ongoing general application of this methodology in commercial breeding programs. Using the results and recommendations from the case study, advantages and disadvantages of application of selection indices versus other methods to crop improvement programs are discussed.

Sugarcane is a high biomass crop grown mostly in rain-fed environments. Water is a key determinant of sugarcane productivity, and in most production regions, varying and sometimes severe water stress occurs. Understanding the extent of genetic variation in response to water stress may allow for better targeted breeding programs. In this study a set of field experiments evaluating 31 sugarcane clones under rain-fed and irrigated conditions was conducted in two sugarcane production areas in Yunnan province, South China. While the water treatments had a large impact on mean cane yield there were little or no genotype × water treatment interactions for cane yield or sugar content at harvest, or for dry biomass sampled about five months (early biomass) after the start of crop growth. The high genetic correlation between well-watered and water stress treatments is consistent with the hypothesis that clone performance under water stress is mostly associated with general vigour rather than traits acting specifically under water stress. From a practical breeding program perspective the results suggest that choice or management of water stress level in selection trials is not a critical consideration for sugarcane breeding programs, and that selection under reasonably well watered conditions will be effective for attaining satisfactory selection gains under at least moderate levels of water stress. Early biomass was positively correlated with yield at final harvest for all water treatments. Resolution of the physiological basis of the high genetic correlations between growth under well-watered and water limited conditions may assist in future breeding efforts.

Genetic variation in traits affecting transpiration efficiency has been reported in sugarcane, but the impact of this variation on yield in a range of production environments needs to be estimated for assessing the priority and selection weightings to apply to these traits in crop improvement programs. A modelling approach may be useful and even necessary for reasonable assessment of these traits across production environments with different and temporally variable levels of water availability. Earlier theoretical modelling using the Agricultural Production Systems Simulator (APSIM)-Sugar module, found that traits affecting transpiration efficiency (TE) and water uptake by roots were important for improving sugarcane grown with highly variable rainfall. However, there were limitations of APSIM-Sugar in accommodating key physiological mechanisms, and this led to a revision of the APSIM-Sugar module described in this paper. Four key features were added to enable genetic variation in TE traits and root water supply (RWS) known to exist, to be modelled and assessed for predicted impact. These features were 1) the response of TE to water stress, 2) the midday flattening of hourly transpiration when plants are stressed, 3) conductance limits to hourly transpiration, which can apply even without stress and 4) the separation of soil hydraulic conductivity ( k) and root length density ( l) rather than the use of combined kl for determining RWS. A dataset of 182 observations of above ground biomass from 13 field experiments of sugarcane were used to check firstly that the new sugarcane module did not affect the simulation results when all the new features were disabled (model stability), secondly to check that the new features did not greatly reduce model performance, and thirdly, to determine the response or sensitivity of yields to the new features. Variation in parameter settings for the new features were based on the best evidence available for genetic variation in these traits, and were set before any testing against observations were made. With these features enabled in partial factorial combinations, the accuracy of the simulation of observed biomass, changed only to a minor extent compared to when no features were enabled. Separating k and l had the most consistent effect on improving model performance. Three additional published experiments with varying levels of imposed water stress were also simulated, with and without the new features. The simulation of biomass yield from two of the experiments was remarkably accurate regardless of which features were used in the simulation. Dry stalk yields reported for the third experiment were simulated accurately when no features were enabled and when midday flattening of transpiration was enabled and separate k and l enabled, one at a time. When a limit was placed on hourly transpiration, simulated TE and yield increased substantially when water was limiting but not in well-watered conditions; where yield was reduced. The new APSIM-Sugar features address the limitations of the original module (developed in 1999) for assessing water use related traits, including TE component traits and root growth. Effects of conductance on TE can now be simulated by limiting maximum hourly transpiration at the leaf level or k and specific root length at the root level. The new sugar module will also allow for better discrimination between sugarcane cultivars, now that vigour traits such leaf area development and radiation use efficiency are linked to root water uptake.

Background Hospital admissions with decompensated chronic alcoholic liver disease have been increasing, leading to increased pressure on intensive care unit services. We aimed to determine the outcome and prognostic factors for patients with alcoholic liver disease requiring admission to intensive care unit. Methods This was a retrospective study over 5 years (January 2006–December 2010) of all intensive care unit admissions with alcoholic liver disease to either of the two Leeds Teaching Hospitals NHS Trust general intensive care units. A detailed case note review was conducted based on a pre-established proforma. Eighty-two patients included. Primary outcome was hospital mortality. Results The overall intensive care unit and hospital mortality were 46% and 67%, respectively. Hospital mortality in patients successfully discharged from intensive care unit with the intent of recovery remained high at 21%. Variceal bleed was the only indicator that had a mortality Conclusion These results are similar to previous studies with no significant improvement in outcomes. Alcoholic liver disease is not a contra-indication to intensive care unit admission but assessment of the individual patient is required. The most appropriate objective factors to guide prognostication are the presenting intensive care unit diagnosis and Sequential Organ Failure Assessment score. First presentation of alcoholic liver disease is not a positive prognostic indicator.

This chapter examines how the success of change initiatives can be increased by designing the change communication process to create alignment between the values underpinning the type of change, the values of the people implementing the change, and the values of the people affected by the change. The authors use Graves' ECLET values systems methodology to show how change agents can understand and identify the dominant values systems within the people and organizations they are working with, which will enable them to express change communication in a way that creates values systems alignment. The chapter begins by examining why change fails. It then moves on to describe Graves' work and then to provide examples of how it can be used to improve the success of change projects. The chapter concludes by suggesting key questions change agents need to ask when undertaking change initiatives.

Due to their osteoconductive and osteoinductive abilities, bioglasses (BGs) have attracted attention in tissue engineering, especially for mineralized tissue. The aim of this study is to review the current state of the art on the effects of BGs produced by sol-gel on cells for dental and periodontal regeneration. The study also discusses associated antibacterial properties. The research was performed by considering the Preferred Reporting Items for Systematic Reviews and the Meta-Analyses (PRISMA) statement. The research ranged 5 years' window time (from January, 01, 2012, to August, 31, 2017) and the relevant studies were identified based on the inclusion/exclusion criteria. A total of 45 articles were selected from 244 initial returns, plus seven further articles coming from other sources were selected for the same purpose. From this systematic study, it is revealed that only 13 of the 52 articles have proved both the ability of BGs to differentiate dental cells at genetic level and their ability of triggering cell-mediated mineralization, but only six of them showed, along with cells, the antibacterial properties of the glasses. This review shows that sol-gel BGs are not toxic, can sustain cell proliferation and differentiation at a genetic level, and can keep the bacterial population under control. Moreover, a standard methodology and an ideal material are suggested. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1210-1227, 2019.

The aim of this study was to assess the influence of CaO/Na2O ratio on the structural and textural properties of mesoporous bioactive glasses generated from an acetic acid catalysed acetate based sol-gel system. The glass network formers (SiO2 and P2O5) were fixed and the network modifiers were varied [75SiO2:XCaO:(15-X)Na2O:10P2O5 where X = 5, 10, 15, in mole percent] such that increasing alkaline earth oxide is compensated by decreasing alkali oxide. The glass properties were assessed using techniques such as XRF, XRD, FTIR, BET/BJH, SEM, TEM and ICP. The rapid gelling of the sol resulted in the deposition of the calcium and sodium acetate precursors on the particle surface which required thermal treatment to facilitate their entry into the glass network. The results of our study demonstrated that the porosity was clearly driven by CaO in the composition possibly due to its inferior fluxing effect in comparison to Na2O. The sample with highest CaO content reached a high surface area and pore volume (535 m2 g−1 and 0.33 cm3 g−1) even in a non-surfactant based preparation suggesting that acetic acid catalysed acetate system favours improved textural properties. In vitro SBF tests confirmed the potential of the sample with highest CaO for earlier apatite formation.

CO2 responsive colloids are of interest for the delivery of active molecules in both pharmaceutical applications and for gas treatment technologies, among others. Primary and secondary organic amines react with CO2 gas in aqueous solution to form ionic carbamates in an exothermic “CO2 sequestration” reaction. Several amines important in this context are 2-aminoethanol, 2,2′-iminodiethanol, and piperazine. We have used small-angle X-ray scattering at a high intensity synchrotron source to demonstrate that triblock copolymer micelles containing carbamate-forming amines change shape upon exposure to CO2. Modeling of the scattering data is used to elucidate the effects of exposure on micelle size and morphology. Electron density distribution within the micelles, derived from the SAXS data, established that the amines interact with the polymer micelles. The products of CO2 exposure, namely, carbamate, bicarbonate anions, and protons, modify the packing of the polymer chains, and occupy the volume within the po...

International audience; Phosphate-based glasses have been attracting attention due to their possible medical applications arising from unique dissolution characteristics in the human body leading to the possibility of new tissue regeneration. In this study, the leaching kinetics of a series of melt-quenched Sr-doped phosphate glasses are presented. Regardless of the presence of Sr, all the glasses have an initial linear and sustained release of the ions followed by a plateau. To guarantee proper nutritional support to the growing tissue during regeneration and to mimic the 3-dimensional architecture of tissues, organic scaffold systems have been developed. However, their poor mechanical strength has limited their application. To overcome this problem, cross-linkers can be used although this then limits the solubility of the materials. To succeed in dealing with such a limitation, in this paper, by freeze-drying, the aforementioned soluble melt-quenched phosphate glasses were combined as powders with collagen fibres from bovine achilles tendon to make degradable scaffolds. The scaffolds were characterized by SEM, EDX and BET. Changes to the dissolution behaviour of the glasses arising from the presence of collagen interacting with the ions leached were reported. Furthermore, the ability of the scaffolds to induce hydroxyapatite (HA) formation was evaluated: one the elaborated scaffold could grow an HA-like layer after a week in SBF. Based on the results obtained, a possible application in restorative dentistry is proposed for one or more materials.

International audience; Background and objectives: Strategies to achieve dentin remineralization is at present an important target of restorative dentistry. Remineralization of dentin by a bioactive material is complete only when the tissue regains its functionality. This is achieved when there is adequate apatite formation which most importantly translates into improved mechanical properties of dentin as a result of intrafibrillar mineralization. Bioactive glass (BAG) is a well-known implant material for bone regeneration and is proven to have excellent ability of apatite formation. Hence, recent studies have proposed BAGs as one of the most desired materials for remineralization of dentin. Therefore the aim of this systematic review was to scope the evidence of bioactive glass to remineralize dentin.Methods: The following research question was formulated: "Is there strong evidence for bioactive glass to remineralize dentin?" Three databases (Web of science, PubMed and Science direct) were scanned independently following PRISMA guidelines. Inclusion and exclusion criteria were set to identify relevant articles based on title and abstract screening. Finally, potentially relevant articles were downloaded and the full text was scrutinized to select the articles included in this review.Results: The first phase of search returned 303 articles. A total of 19 papers with full text were scrutinized for inclusion, of which 3 papers were chosen for the final synthesis. All three studies confirm that BAG treatment leads to enhanced apatite formation in dentin. Only 1 of the 3 studies has reported the mechanical properties of dentin after BAG treatment and it revealed that the Young's modulus and flexural bend strength of BAG treated dentin were much lower than natural dentin even though they had similar apatite content.Conclusions: This review highlights the importance of assessing the mechanical properties of dentin alongside to the newly formed apatite content in order to prove BAGs efficiency to remineralize this tissue. Though studies have confirmed that BAGs stimulate excellent apatite formation in dentin, it should be concluded that there isn't sufficient evidence for bioactive glass to effectively remineralize this tissue as the mechanical properties of the BAG treated dentin haven't been well explored.

Objective Nowadays bioactive glasses are finding increasing applications in medical practice due to their ability to stimulate re-mineralisation. However, they are intrinsically brittle materials and the study of new compositions will open up new scenarios enhancing their mechanical properties and maintaining the high bioactivity for a broader range of applications. This systematic review aims to identify the relationship between the composition of bioactive glasses used in medical applications and their influence on the mechanical and biological properties. Methods Various electronic databases (PubMed, Science Direct) were used for collecting articles on this subject. This research includes papers from January 2011 to March 2016. PRISMA guidelines for systematic review and meta-analysis have been used. 109 abstracts were collected and screened, 68 articles were read as relevant articles and a total of 22 papers were finally selected for this study. Results Most of the studies obtained enhanced mechanical properties and the conservation of bioactivity behaviours; although a lack of homogeneity in the characterization methods makes it difficult to compare data. Significance New compositions of bioactive glasses incorporating specific ions and the addition in polymers will be the most important direction for future researches in developing new materials for medical applications and especially for dentistry.

The Australian Defence Science and Technology Organisation (DSTO) was recently tasked with evaluating an in-service fatigue crack discovered in the primary structure of an Australian Army Black Hawk helicopter. This crack, discovered early in the affected components service life, was quite large and subsequent fractographic analysis generated substantial information with respect to its growth characteristics. Consequently, it was decided to use this in-service fatigue crack to test the ability of those methods and technologies being developed at DSTO to model and assess a ‘real’ example of helicopter airframe fatigue cracking. This paper details the process of analysing an in-service fatigue crack using methods and technologies developed and/or improved at DSTO in the areas of visualisation, fatigue spectra generation, load and stress analysis, and crack growth prediction. Results will highlight the effectiveness of the methods and techniques in modelling the observed fatigue damage and areas where further improvements are required.

Controlling vapour pressure is necessary for the viability of aqueous ammonia solutions in commercial applications such as refrigeration. In this study, Gibbs ensemble Monte Carlo (GEMC) simulations were used to calculate the vapour–liquid equilibrium (VLE) of ammonia–water–MCl mixtures, M = Na or Cs, within the isobaric–isothermal- (NpT-) ensemble. The results indicate that in the presence of alkali metal additives, there is a non-negligible ‘salting-in’ effect for ammonia in the liquid phase. Experimental measurements of the liquid phase concentration of ammonia confirm the GEMC results i.e. the vapour loss rates in systems containing ionic additives is slightly lower. Gibbs ensemble Monte Carlo simulations also indicate that ammonia prefers to solvate aqueous cations as a result of electrostatic interactions. Ab-initio calculations show that the M+–ammonia complex is energetically more stable than the M+–water complex. The difference in the binding free energy Δ(ΔG bind(M+–NH3)−ΔG bind(M+–H2O)) depends on the size of the cation and is highest for the smallest tight cations (e.g. Li+) and lowest for the most polarisable cations (Cs+).

The amine-based post-combustion capture (PCC) of CO 2 is an option being considered for the reduction of anthropogenic CO 2 emissions. PCC plants will be attached or retro-fitted to fossil-fuel fired power generating infrastructure (i.e. large stationary point sources) during the transition to renewable energy, which is expected to take place over several decades. Despite being an established technology widely used to remove CO 2 from small scale-commercial process such as natural gas sweetening, there are many challenges that must be overcome before large scale implementation of the process can be realised. Some of these challenges include: • Reducing plant capital costs • Reducing the energy required for solvent regeneration/release of captured CO • Reducing solvent degradation in the presence of O2 and other flue gas contaminants, such as NOx and SOx, and • Reducing and understanding the environmental impact i.e. the potential of solvents and solvent degradation products to be released into the environment through off-gases, leaks or spills, and any associated impact this might have. Several recent research articles1-3 have highlighted the propensity of amine-based solvents to undergo certain chemical transformations, both in the condensed and aqueous phases, which produce harmful materials such as nitrosamines and nitramines. The formation and emission of nitrosated amines from the PCC process has not been fully investigated, although it is now the focus of some research agencies in Europe and Australasia. Nitrosamine formation mechanisms are presented in relation to the post- combustion capture of CO 2 with aqueous amine solvents. The relative merits of nitrosamine mitigation strategies are also discussed. In particular the susceptibility of several nitrosamines to UV destruction is explored; the results are compared with TD-DFT results which predict excitation energies with good accuracy. The rate of destruction versus UV wavelength is also discussed, with a view to understanding which electronic transition facilitates decomposition

We propose a complete process for designing, simulating, and fabricating synthetic skin for an animatronics character that mimics the face of a given subject and its expressions. The process starts with measuring the elastic properties of a material used to manufacture synthetic soft tissue. Given these measurements we use physicsbased simulation to predict the behavior of a face when it is driven by the underlying robotic actuation. Next, we capture 3D facial expressions for a given target subject. As the key component of our process, we present a novel optimization scheme that determines the shape of the synthetic skin as well as the actuation parameters that provide the best match to the target expressions. We demonstrate this computational skin design by physically cloning a real human face onto an animatronics figure. © 2012 ACM 0730-0301/2012/08-ART118.

Chromosome doubling in megaspores of sugarcane was first reported over 70 years ago and was seen primarily in interspecific crosses between Saccharum officinarum and Saccharum spontaneum. Since then, there has been robust debate on the mechanism(s) responsible for this doubling with hypotheses ranging from second division restitution (SDR), post-meiotic restitution to fusion of the two innermost cells of the megaspore tetrad. In the present study, we sought to answer this question using molecular marker data from a cross which demonstrated 2n + n chromosome transmission between an S. officinarum clone (IJ76-514; 2n transmission) and a commercial hybrid (Q165 ; n transmission). Molecular marker data from four other bi-parental crosses were used to form a “base-line” for expected segregation ratios (n + n transmission). Comparison of segregation ratios showed that 2n transmission from the S. officinarum clone could be identified by the increased segregation ratios, a characteristic of both SDR and tetrad cell fusion. Simulation was then undertaken based on current understandings of sugarcane meiosis, to determine if the observed segregation ratios matched those simulated for SDR/tetrad cell fusion. Analysis of the simulation confirmed that most and perhaps all progeny appear to have been formed from a mechanism akin to SDR/tetrad cell fusion. The genetic consequences of this are discussed.

This review examined the burden of alcohol-related liver disease (ALD) in the intensive care unit, which is increasing, and whether scoring systems can assist in judging prognosis. Embase, Medline and internet databases were searched for relevant articles whose quality was then scored using the Centre for Evidence-Based Medicine’s (CEBM) critical appraisal tool. Unit mortality of patients with ALD admitted to intensive care in these studies was between 40-50%. In comparison with liver-specific prognostic scoring, physiological scoring systems discriminated better between survivors and nonsurvivors. This is likely to be a reflection of the fact that patients with ALD in intensive care tend to die of multi-organ failure rather than isolated acute liver failure.

Erianthus arundinaceus, a wild relative of sugarcane has a number of traits including tolerance to environmental stresses desired by sugarcane breeders. The value of genetic diversity studies in providing useful information for introgression breeding and germplasm conservation is well known. A previous study reported little genetic diversity in a number of Indonesian E. arundinaceus while Indian E . arundinaceus was more diverse. A small number of Chinese E. arundinaceus was observed as being relatively diverse. However, an assessment of the genetic diversity of E. arundinaceus from the major geographical areas in the world has not been reported before. In this study, 207 E. arundinaceus accessions from China, Indonesia, India, New Guinea, Philippines and Vietnam were sampled for genetic diversity analysis using AFLP markers. Three AFLP primer combinations generated 286 markers in total, with the percentage of polymorphism observed being 99.3%. A dendrogram and PCA diagram were constructed based on the matrix of similarity analyzed with UPGMA method by NTSYS software. The results showed that: (1) a high level of diversity found within the Chinese collection compared with the Indonesian collection and (2) there was a general division amongst clones from China based on those collected from eastern versus western parts of the country, and clones from Yunnan province (western China) were the most diverse.

The reaction between CO2 and aqueous amines to produce a charged carbamate product plays a crucial role in post-combustion capture chemistry when primary and secondary amines are used. In this paper, we report the low energy negative-ion CID results for several anionic carbamates derived from primary and secondary amines commonly used as post-combustion capture solvents. The study was performed using the modern equivalent of a triple quadrupole instrument equipped with a T-wave collision cell. Deuterium labeling of 2-aminoethanol (1,1,2,2,-d4-2-aminoethanol) and computations at the M06-2X/6-311++G(d,p) level were used to confirm the identity of the fragmentation products for 2-hydroxyethylcarbamate (derived from 2-aminoethanol), in particular the ions CN−, NCO− and facile neutral losses of CO2 and water; there is precedent for the latter in condensed phase isocyanate chemistry. The fragmentations of 2-hydroxyethylcarbamate were generalized for carbamate anions derived from other capture amines, including ethylenediamine, diethanolamine, and piperazine. We also report unequivocal evidence for the existence of carbamate anions derived from sterically hindered amines (Tris(2-hydroxymethyl)aminomethane and 2-methyl-2-aminopropanol). For the suite of carbamates investigated, diagnostic losses include the decarboxylation product (−CO2, 44 mass units), loss of 46 mass units and the fragments NCO− (m/z 42) and CN− (m/z 26). We also report low energy CID results for the dicarbamate dianion (−O2CNHC2H4NHCO2−) commonly encountered in CO2 capture solution utilizing ethylenediamine. Finally, we demonstrate a promising ion chromatography-MS based procedure for the separation and quantitation of aqueous anionic carbamates, which is based on the reported CID findings. The availability of accurate quantitation methods for ionic CO2 capture products could lead to dynamic operational tuning of CO2 capture-plants and, thus, cost-savings via real-time manipulation of solvent regeneration energies. Electronic supplementary material The online version of this article (doi:10.1007/s13361-011-0161-5) contains supplementary material, which is available to authorized users.

During the process of exploring aqueous piperazine chemistry under simulated flue-gas scrubbing conditions, positive-ion electrospray ionisation mass spectrometric (ESI-MS) analyses of the resulting reaction mixtures in a triple quadrupole system revealed the presence of peaks at m/z 116 and 145, the putative N-nitroso derivatives of piperazine. Confirmation of the presence of these species in the reaction mixtures was achieved using collision-induced dissociation experiments. A purchased standard, together with in-house synthesised N-nitrosopiperazine standards (including N-nitroso derivatives derived from deuterium-labelled precursor materials), were used for this purpose. Across a small range of collision energies, large fluctuations in the abundance of the two major product ions of protonated N-nitrosopiperazine, m/z 86 and 85, were observed. Using B3LYP/6-311 + +G(d,p) computations, the potential energy surface was determined for loss of NO and [H,N,O]. At an activation energy slightly in excess of 1 eV, intramolecular isomerisation precedes loss of NO (m/z 86) via a 4,1 H-shift, and at activation energies between 2.1-2.3 eV, consecutive loss of NO and atomic hydrogen competes with the direct loss of nitrosyl hydride (m/z 85). It is recommended that any multiple reaction monitoring method for quantifying N-nitrosopiperazines at low collision energies use the sum of both transitions (m/z 116 ← 85, m/z 116 ← 86) to avoid errors that could be introduced by subtle changes in ES source conditions or collision voltages. This approach is adopted in an HPLC/MS/MS method used to monitor the degradation of N-nitrosopiperazine exposed to (i) broad-band UV light and (ii) heat typical of an amine regeneration (stripper) tower. The results reveal that aqueous N-nitrosopiperazine is thermally stable at 150°C but will degrade slowly upon exposure to UV light.

Diversity Arrays Technology (DArT) provides whole genome profiling for hundreds to thousands of polymorphic markers in a single assay using a high-throughput microarray platform. The presented work aimed to establish DArT genotyping for the genetically challenging genome of sugarcane. Due to the genome complexity of this sugar-producing crop of high economic importance, an application of DArT genotyping to this species required extensive testing and optimization. As the method of genome complexity reduction determines the efficiency of polymorphism identification in DArT, various approaches and several methods were tested, in order to establish the most optimal. The sugarcane DArT markers generated with these established methods identified high genetic differentiation of sugarcane ancestral species from modern cultivars, in agreement with the data available for other types of molecular markers for this crop. The majority of sugarcane DArT markers segregated in a Mendelian fashion and were readily incorporated into the framework genetic map. As the DArT markers are sequence-ready genomic clones, we sequenced 384 clones and found that one-third of sequenced markers came from the transcribed portion of the sugarcane genome. The presented results further validate the potential of DArT technology in providing cost-effective genetic profiles for plants, irrespective of their genome complexity, for effective applications in molecular-assisted breeding, diversity analysis or genetic identity testing.

The identification of markers linked to quantitative trait loci (QTLs) for increased sugar accumulation could improve the effectiveness of current breeding strategies in sugarcane. Progeny from a cross between a high sucrose producing cultivar, Open image in new window (denotes Australian plant breeding rights), and a Saccharum officinarum clone, IJ76-514 were grown in two field experiments in different years, and evaluated in the early and mid-season phases of crop maturity, to identify robust QTLs in Open image in new window affecting sucrose content in cane. Using an extensive genetic map constructed for Open image in new window with over 1,000 AFLP and SSR markers, a total of 37 QTLs were identified for brix and pol of which, 16 were detected in both experiments. Of these 37 QTL, 30 were clustered into 12 genomic regions in six of the eight homo(eo)logous groups. Each QTL explained from 3 to 9% of the phenotypic variation observed. Both positive and negative effects were identified and the location of the QTLs on linkage groups belonging to the same homo(eo)logy group suggested that a number of the QTLs were allelic forms of the same genes. Of the 37 QTLs identified, the majority were significant in both early and mature cane, but 8 were identified as early specific QTLs and 9 as mature cane QTLs. In total, 97 interactions were significant (P

Erianthus rockii is a drought and cold tolerant wild relative of sugar cane from China that is currently being used in sugar cane introgression programs. It has not been described outside of China. Although classified as an Erianthus species using morphological characters, its relationship with other Erianthus species and other species in the Saccharum complex is not well understood. Genotypes representing seventeen species from five genera in the Saccharum complex were evaluated with approximately 200 microsatellite (SSR) and amplified fragment length polymorphism (AFLP) markers and similarity matrices constructed. Principal component analysis (PCA) was undertaken separately with the AFLP and SSR data. The results from both data sets were very similar and suggested that E. rockii was distinct from other Erianthus and Saccharum species. E. rockii clustered with E. fulvus and two Miscanthus species, mid-way between the major Saccharum and Erianthus clusters.

Erianthus arundinaceus has a number of important agronomic traits including good ratooning ability, tolerance to both drought and water logging, disease resistance and vigour and is of interest as a potential source of parental germplasm to sugarcane breeders. However, to date, attempts to produce fertile hybrids between sugarcane (Saccharum spp.) and E. arundinaceus have been unsuccessful. Microsatellite markers that generated genus-specific markers and were highly polymorphic within sugarcane were identified. The microsatellite markers and 5S rDNA PCR were used to screen intergeneric (F 1 ) clones from Saccharum officinarum x E. arundinaceus crosses, and two Saccharum backcross progeny (BC 1 ) populations derived from crosses between selected F 1 clones and sugarcane (Saccharum spp.), to identify genuine Saccharum spp. BC 1 progeny. The 5S rDNA PCR marker and highly polymorphic microsatellites with Erianthus-specific bands confirmed the F 1 parent of the two putative BC 1 populations was a S. officinarum x E. arundinaceus hybrid and allowed the identification of the genuine BC 1 progeny from selfs of the F 1 parent. This is the first verification of BC 1 progeny from an F 1 intergeneric hybrid x sugarcane (Saccharum spp.) clone with molecular markers and confirms the introgression of E. arundinaceus germplasm into sugareane. It should now be possible to exploit genes of value from E. arundinaceus in sugarcane breeding programmes.

Author for correspondence e-mail: lynne.mcintyre@csiro.au; International audience; Mandalay is an important Saccharum spontaneum clone used historically in Australian sugarcane breeding programs, and has given rise to many valuable cultivars. In order to better understand the genetic contribution of Mandalay to Australian varieties and elite parental material, a combined pedigree and quantitative trait loci (QTL) mapping approach was undertaken. A genetic map containing 400 single-dose markers was constructed for the Australian sugarcane clone MQ77–340, one parent of an Australian sugarcane population (Q117 · MQ77–340), using amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers. This cultivar was selected because it is a direct descendent of Mandalay; its grandparents are Korpi, a S. o.cinarum clone, and Mandalay. The 400 markers were scattered onto 101 linkage groups (LGs) with an estimated map length of 3582 cM. The ancestral origin of all of the markers was determined with approximately 25% of the markers shown to originate from Mandalay, and a similar percentage from Korpi. Of the 101 LGs, 65 contained markers originating from Mandalay and/or Korpi. QTL analysis was undertaken using the map and 3 years of field data for three sugar-related traits (pol, brix, and CCS) and using single year .eld data for .bre, stalk weight and cane and sugar yield. Markers from both Mandalay and Korpi were found to be associated with both positive and negative effects on all of the traits analysed

In sugarcane breeding programs, parents used in crosses are classified as male or female based on relative amounts of viable pollen produced. Usually the ‘female’ parent produces some pollen, albeit at a lower level than the ‘male’ parent. The possibility of selfing and associated problems have long been recognised by breeders. A high level of selfing may seriously bias estimates of breeding value of parents and affect the reliability of family means for identifying superior crosses. However, there is no reliable information reported indicating the level to which selfing is occurring in sugarcane crosses. The level of selfing was evaluated in eight Australian sugarcane crosses using RAPD markers. The crosses were selected as exhibiting variable levels of performance, as judged by measurements of commercial cane sugar (CCS), cane yield (TCH) and sugar yield (TSH) in plots consisting of random progeny clones. Five to eight male-specific RAPD bands were identified for each cross and used to screen twenty-eight to thirty-eight progeny from each cross. Selfed progeny were identified in each cross on the basis of absence of any male-specific RAPD bands after screening with at least 5 such RAPDs. Levels of selfing ranged from 0 to17.6%, with most of the crosses exhibiting zero or low levels of selfing. Although only a limited number of sugarcane crosses have been studied, this survey suggests that unwanted selfing is not a significant problem in the Australian sugarcane breeding program.

Specific products and their relative abundances observed in gas-phase collision-induced dissociation experiments for [amine-H + CO2 + H2O](-) reflect the behaviour of the bulk aqueous amines in the presence of CO2.

During the process of exploring aqueous piperazine chemistry under simulated flue-gas scrubbing conditions, positive-ion electrospray ionisation mass spectrometric (ESI-MS) analyses of the resulting reaction mixtures in a triple quadrupole system revealed the presence of peaks at m/z 116 and 145, the putative N-nitroso derivatives of piperazine. Confirmation of the presence of these species in the reaction mixtures was achieved using collision-induced dissociation experiments. A purchased standard, together with in-house synthesised N-nitrosopiperazine standards (including N-nitroso derivatives derived from deuterium-labelled precursor materials), were used for this purpose. Across a small range of collision energies, large fluctuations in the abundance of the two major product ions of protonated N-nitrosopiperazine, m/z 86 and 85, were observed. Using B3LYP/6-311 + +G(d,p) computations, the potential energy surface was determined for loss of NO and [H,N,O]. At an activation energy slightly in excess of 1 eV, intramolecular isomerisation precedes loss of NO (m/z 86) via a 4,1 H-shift, and at activation energies between 2.1-2.3 eV, consecutive loss of NO and atomic hydrogen competes with the direct loss of nitrosyl hydride (m/z 85). It is recommended that any multiple reaction monitoring method for quantifying N-nitrosopiperazines at low collision energies use the sum of both transitions (m/z 116 ← 85, m/z 116 ← 86) to avoid errors that could be introduced by subtle changes in ES source conditions or collision voltages. This approach is adopted in an HPLC/MS/MS method used to monitor the degradation of N-nitrosopiperazine exposed to (i) broad-band UV light and (ii) heat typical of an amine regeneration (stripper) tower. The results reveal that aqueous N-nitrosopiperazine is thermally stable at 150°C but will degrade slowly upon exposure to UV light.

Among persons who were at risk for infection with 2009 H1N1 virus, being born before 1957 was associated with a lower infection risk.