Interstellar molecules : Conversion or C3O-. to C3O in the gas phase

Neutral C3O has been prepared by collision induced neutralisation of the precursor radical anion formed by the reaction C-=C-CO-OEt --> C3O-. +EtO. . The similar neutralisaaion reionisation (-NR+) and charge reversal (CR) spectra of C3O-. indicate that the potential surfaces of C3O and C3O+. show favourable vertical Franck-Condon overlap, This suggests that the bond connectivities of anion, neutral and cation C3O are the same. Copyright (C) 1999 John Wiley & Sons, Ltd.

Interstellar molecules. Conversion or C3O-. to C3O in the gas phase

Neutral C3O has been prepared by collision induced neutralisation of the precursor radical anion formed by the reaction C-=C-CO-OEt --> C3O-. +EtO. The similar neutralisaaion reionisation (-NR+) and charge reversal (CR) spectra of C3O-. indicate that the potential surfaces of C3O and C3O+. show favourable vertical Franck-Condon overlap, This suggests that the bond connectivities of anion, neutral and cation C3O are the same. Copyright (C) 1999 John Wiley & Sons, Ltd.

Treatment plan complexity metrics for predicting IMRT pre-treatment quality assurance results

The planning of IMRT treatments requires a compromise between dose conformity (complexity) and deliverability. This study investigates established and novel treatment complexity metrics for 122 IMRT beams from prostate treatment plans. The Treatment and Dose Assessor software was used to extract the necessary data from exported treatment plan files and calculate the metrics. For most of the metrics, there was strong overlap between the calculated values for plans that passed and failed their quality assurance (QA) tests. However, statistically significant variation between plans that passed and failed QA measurements was found for the established modulation index and for a novel metric describing the proportion of small apertures in each beam. The ‘small aperture score’ provided threshold values which successfully distinguished deliverable treatment plans from plans that did not pass QA, with a low false negative rate.

Disparate companions : tissue engineering meets cancer research

Recreating an environment that supports and promotes fundamental homeostatic mechanisms is a significant challenge in tissue engineering. Optimizing cell survival, proliferation, differentiation, apoptosis and angiogenesis, and providing suitable stromal support and signalling cues are keys to successfully generating clinically useful tissues. Interestingly, those components are often subverted in the cancer setting, where aberrant angiogenesis, cellular proliferation, cell signalling and resistance to apoptosis drive malignant growth. In contrast to tissue engineering, identifying and inhibiting those pathways is a major challenge in cancer research. The recent discovery of adult tissue-specific stem cells has had a major impact on both tissue engineering and cancer research. The unique properties of these cells and their role in tissue and organ repair and regeneration hold great potential for engineering tissue-specific constructs. The emerging body of evidence implicating stem cells and progenitor cells as the source of oncogenic transformation prompts caution when using these cells for tissue-engineering purposes. While tissue engineering and cancer research may be considered as opposed fields of research with regard to their proclaimed goals, the compelling overlap in fundamental pathways underlying these processes suggests that cross-disciplinary research will benefit both fields. In this review article, tissue engineering and cancer research are brought together and explored with regard to discoveries that may be of mutual benefit.

Ambiguity Acceptance Testing : A Comparison of the Ratio Test and Difference Test

Integer ambiguity resolution is an indispensable procedure for all high precision GNSS applications. The correctness of the estimated integer ambiguities is the key to achieving highly reliable positioning, but the solution cannot be validated with classical hypothesis testing methods. The integer aperture estimation theory unifies all existing ambiguity validation tests and provides a new prospective to review existing methods, which enables us to have a better understanding on the ambiguity validation problem. This contribution analyses two simple but efficient ambiguity validation test methods, ratio test and difference test, from three aspects: acceptance region, probability basis and numerical results. The major contribution of this paper can be summarized as: (1) The ratio test acceptance region is overlap of ellipsoids while the difference test acceptance region is overlap of half-spaces. (2) The probability basis of these two popular tests is firstly analyzed. The difference test is an approximation to optimal integer aperture, while the ratio test follows an exponential relationship in probability. (3) The limitations of the two tests are firstly identified. The two tests may under-evaluate the failure risk if the model is not strong enough or the float ambiguities fall in particular region. (4) Extensive numerical results are used to compare the performance of these two tests. The simulation results show the ratio test outperforms the difference test in some models while difference test performs better in other models. Particularly in the medium baseline kinematic model, the difference tests outperforms the ratio test, the superiority is independent on frequency number, observation noise, satellite geometry, while it depends on success rate and failure rate tolerance. Smaller failure rate leads to larger performance discrepancy.

Polarization of forecast densities : a new approach to time series classification

Time series classification has been extensively explored in many fields of study. Most methods are based on the historical or current information extracted from data. However, if interest is in a specific future time period, methods that directly relate to forecasts of time series are much more appropriate. An approach to time series classification is proposed based on a polarization measure of forecast densities of time series. By fitting autoregressive models, forecast replicates of each time series are obtained via the bias-corrected bootstrap, and a stationarity correction is considered when necessary. Kernel estimators are then employed to approximate forecast densities, and discrepancies of forecast densities of pairs of time series are estimated by a polarization measure, which evaluates the extent to which two densities overlap. Following the distributional properties of the polarization measure, a discriminant rule and a clustering method are proposed to conduct the supervised and unsupervised classification, respectively. The proposed methodology is applied to both simulated and real data sets, and the results show desirable properties.

Harnessing the influence of reactive edges and defects of graphene substrates for achieving complete cycle of room-temperature molecular sensing

Molecular doping and detection are at the forefront of graphene research, a topic of great interest in physical and materials science. Molecules adsorb strongly on graphene, leading to a change in electrical conductivity at room temperature. However, a common impediment for practical applications reported by all studies to date is the excessively slow rate of desorption of important reactive gases such as ammonia and nitrogen dioxide. Annealing at high temperatures, or exposure to strong ultraviolet light under vacuum, is employed to facilitate desorption of these gases. In this article, the molecules adsorbed on graphene nanoflakes and on chemically derived graphene-nanomesh flakes are displaced rapidly at room temperature in air by the use of gaseous polar molecules such as water and ethanol. The mechanism for desorption is proposed to arise from the electrostatic forces exerted by the polar molecules, which decouples the overlap between substrate defect states, molecule states, and graphene states near the Fermi level. Using chemiresistors prepared from water-based dispersions of single-layer graphene on mesoporous alumina membranes, the study further shows that the edges of the graphene flakes (showing p-type responses to NO2 and NH3) and the edges of graphene nanomesh structures (showing n-type responses to NO2 and NH3) have enhanced sensitivity. The measured responses towards gases are comparable to or better than those which have been obtained using devices that are more sophisticated. The higher sensitivity and rapid regeneration of the sensor at room temperature provides a clear advancement towards practical molecule detection using graphene-based materials.

Boundary swaying

This practice-led research is positioned within my ongoing enquiry into the dancer’s experience and role within the creative process. Gins and Arakawa (1997) and Keane (2007) speak to the unsatisfactory reliance on discipline boundaries, to describe the dynamic lived-experience of interaction. This theorising is of application to this project, which examines creative agency through the lens of Arakawa and Gins’ language prompt, boundary-swaying. In this project the boundaries of movement creator, performer and director overlap and blur through the use of improvisation and multiple cameras. All contributors are invested creatively and compositionally in the ensuing dynamic collaboration, wearing many hats, ‘conceiver, creative thinker, teacher and learner’ (McKechnie 2005, 93; Stevens & McKechnie 2005, 250). This project asked the question, how can the work of Arakawa and Gins to agitate, disrupt, and transform the modus operandi of creative practice between choreographer and practice, dancer and practice and choreographer and dancer? The use of Arakawa and Gins’ philosophy and language prompts within this project stimulated and positively influenced the established creative relationship of researcher and choreographer/artist in the following ways: • Foregrounded the dancers tacit knowledge, first-hand experience, know-how and embodied savviness; • Promoted artistic collaboration, illuminating new creative possibilities, choices and innovation; • Facilitated the distribution of creative authority and agency. This creative work was presented as part of the AG3 ONLINE: the Third International Arakawa and Gins - Architecture and Philosophy Conference. The work was vetted for inclusion by an international panel of examiners.

4DCT radiotherapy for NSCLC: A review of planning methods

Purpose To establish whether the use of a passive or active technique of planning target volume (PTV) definition and treatment methods for non-small cell lung cancer (NSCLC) deliver the most effective results. This literature review assesses the advantages and disadvantages in recent studies of each, while assessing the validity of the two approaches for planning and treatment. Methods A systematic review of literature focusing on the planning and treatment of radiation therapy to NSCLC tumours. Different approaches which have been published in recent articles are subjected to critical appraisal in order to determine their relative efficacy. Results Free-breathing (FB) is the optimal method to perform planning scans for patients and departments, as it involves no significant increase in cost, workload or education. Maximum intensity projection (MIP) is the fastest form of delineation, however it is noted to be less accurate than the ten-phase overlap approach for computed tomography (CT). Although gating has proven to reduce margins and facilitate sparing of organs at risk, treatment times can be longer and planning time can be as much as 15 times higher for intensity modulated radiation therapy (IMRT). This raises issues with patient comfort and stabilisation, impacting on the chance of geometric miss. Stereotactic treatments can take up to 3 hours to treat, along with increases in planning and treatment, as well as the additional hardware, software and training required. Conclusion Four-dimensional computed tomography (4DCT) is superior to 3DCT, with the passive FB approach for PTV delineation and treatment optimal. Departments should use a combination of MIP with visual confirmation ensuring coverage for stage 1 disease. Stages 2-3 should be delineated using ten-phases overlaid. Stereotactic and gated treatments for early stage disease should be used accordingly; FB-IMRT is optimal for latter stage disease.

Annealing-free high-mobility diketopyrrolopyrrole-quaterthiophene copolymer for solution-processed organic thin film transistors

A donor-acceptor polymer semiconductor, PDQT, comprising diketopyrrolopyrrole (DPP) and β-unsubstituted quaterthiophene (QT) for organic thin film transistors (OTFTs) is reported. This polymer forms ordered layer-by-layer lamellar packing with an edge-on orientation in thin films even without thermal annealing. The strong intermolecular interactions arising from the fused aromatic DPP moiety and the DPP-QT donor-acceptor interaction facilitate the spontaneous self-assembly of the polymer chains into close proximity and form a large π-π overlap, which are favorable for intermolecular charge hopping. The well-interconnected crystalline grains form efficient intergranular charge transport pathways. The desirable chemical, electronic, and morphological structures of PDQT bring about high hole mobility of up to 0.97 cm2/(V·s) in OTFTs with polymer thin films annealed at a mild temperature of 100 °C and similarly high mobility of 0.89 cm2/(V·s) for polymer thin films even without thermal annealing.

Understanding Heliothine (Lepidoptera: Heliothinae) pests: What is a host plant?

Heliothine moths (Lepidoptera: Heliothinae) include some of the world's most devastating pest species. Whereas the majority of nonpest heliothinae specialize on a single plant family, genus, or species, pest species are highly polyphagous, with populations often escalating in size as they move from one crop species to another. Here, we examine the current literature on heliothine host-selection behavior with the aim of providing a knowledge base for research scientists and pest managers. We review the host relations of pest heliothines, with a particular focus on Helicoverpa armigera (Hubner), the most economically damaging of all heliothine species. We then consider the important question of what constitutes a host plant in these moths, and some of the problems that arise when trying to determine host plant status from empirical studies on host use. The top six host plant families in the two main Australian pest species (H. armigera and Helicoverpa punctigera Wallengren) are the same and the top three (Asteraceae, Fabaceae, and Malvaceae) are ranked the same (in terms of the number of host species on which eggs or larvae have been identified), suggesting that these species may use similar cues to identify their hosts. In contrast, for the two key pest heliothines in the Americas, the Fabaceae contains approximate to 1/3 of hosts for both. For Helicoverpa zea (Boddie), the remaining hosts are more evenly distributed, with Solanaceae next, followed by Poaceae, Asteraceae, Malvaceae, and Rosaceae. For Heliothis virescens (F.), the next highest five families are Malvaceae, Asteraceae, Solanaceae, Convolvulaceae, and Scrophulariaceae. Again there is considerable overlap in host use at generic and even species level. H. armigera is the most widely distributed and recorded from 68 plant families worldwide, but only 14 families are recorded as a containing a host in all geographic areas. A few crop hosts are used throughout the range as expected, but in some cases there are anomalies, perhaps because host plant relation studies are not comparable. Studies on the attraction of heliothines to plant odors are examined in the context of our current understanding of insect olfaction, with the aim of better understanding the connection between odor perception and host choice. Finally, we discuss research into sustainable management of pest heliothines using knowledge of heliothine behavior and ecology. A coordinated international research effort is needed to advance our knowledge on host relations in widely distributed polyphagous species instead of the localized, piecemeal approaches to understanding these insects that has been the norm to date.

Escherichia coli isolates causing asymptomatic bacteriuria in catheterized and noncatheterized individuals possess similar virulence properties

Urinary tract infections (UTIs) are among the most common infectious diseases of humans, with Escherichia coli being responsible for >80% of all cases. Asymptomatic bacteriuria (ABU) occurs when bacteria colonize the urinary tract without causing clinical symptoms and can affect both catheterized patients (catheter-associated ABU [CA-ABU]) and noncatheterized patients. Here, we compared the virulence properties of a collection of ABU and CA-ABU nosocomial E. coli isolates in terms of antibiotic resistance, phylogenetic grouping, specific UTI-associated virulence genes, hemagglutination characteristics, and biofilm formation. CA-ABU isolates were similar to ABU isolates with regard to the majority of these characteristics; exceptions were that CA-ABU isolates had a higher prevalence of the polysaccharide capsule marker genes kpsMT II and kpsMT K1, while more ABU strains were capable of mannose-resistant hemagglutination. To examine biofilm growth in detail, we performed a global gene expression analysis with two CA-ABU strains that formed a strong biofilm and that possessed a limited adhesin repertoire. The gene expression profile of the CA-ABU strains during biofilm growth showed considerable overlap with that previously described for the prototype ABU E. coli strain, 83972. This is the first global gene expression analysis of E. coli CA-ABU strains. Overall, our data suggest that nosocomial ABU and CA-ABU E. coli isolates possess similar virulence profiles.

Morphometric modelling of ageing in the human pubic symphysis : sexual dimorphism in an Australian population

Despite the prominent use of the pubic symphysis for age estimation in forensic anthropology, little has been documented regarding the quantitative morphological and micro-architectural changes of this surface. Specifically, utilising post-mortem computed tomography data from a large, contemporary Australian adult population, this study aimed to evaluate sexual dimorphism in the morphology and bone composition of the symphyseal surface; and temporal characterisation of the pubic symphysis in individuals of advancing age. The sample consisted of multi-slice computed tomography (MSCT) scans of the pubic symphysis(slice thickness: 0.5 mm, overlap: 0.1 mm) of 200 individuals of Caucasian ancestry aged 15–70 years, obtained in 2011. Surface rendering reconstruction of the symphyseal surface was conducted in OsiriX1 (v.4.1) and quantitative analyses in Rapidform XOSTM and OsteomeasureTM. Morphometric variables including inter-pubic distance, surface area, circumference, maximum height and width of the symphyseal surface and micro-architectural assessment of cortical and trabecular bone compositions were quantified using novel automated engineering software capabilities. The major results of this study are correlated with the macroscopic ossification and degeneration pattern of the symphyseal surface, demonstrating significant age-related changes in the morphometric and bone tissue variables between 15 and 70 years. Regardless of sex, the overall dimensions of the symphyseal surface increased with age, coupled with a decrease in bone mass in the trabecular and cortical bone compartments. Significant differences between the ventral, dorsal and medial cortical surfaces were observed, which may be correlated to bone formation activity dependent on muscle activity and ligamentous attachments. Our study demonstrates significant sexual dimorphism at this site, with males exhibiting greater surface dimensions than females. These baseline results provide a detailed insight into the changes in the structure of the pubic symphysis with ageing and sexually dimorphic features associated with the cortical and trabecular bone profiles.

Theorizing the use of multiple conceptual models in combination

Conceptual modelling continues to be an important means for graphically capturing the requirements of an information system. Observations of modelling practice suggest that modellers often use multiple conceptual models in combination, because they articulate different aspects of real-world domains. Yet, the available empirical as well as theoretical research in this area has largely studied the use of single models, or single modelling grammars. We develop a Theory of Combined Ontological Coverage by extending an existing theory of ontological expressiveness of conceptual modelling grammars. Our new theory posits that multiple conceptual models are used to increase the maximum coverage of the real-world domain being modelled, whilst trying to minimize the ontological overlap between the models. We illustrate how the theory can be applied to analyse sets of conceptual models. We develop three propositions of the theory about evaluations of model combinations in terms of users’ selection, understandability and usefulness of conceptual models.

Aggregating energy supply and demand

Energy usage in general, and electricity usage in particular, are major concerns internationally due to the increased cost of providing energy supplies and the environmental impacts of electricity generation using carbon-based fuels. If a "systems" approach is taken to understanding energy issues then both supply and demand need to be considered holistically. This paper examines two research projects in the energy area with IT tools as key deliverables, one examining supply issues and the other studying demand side issues. The supply side project used hard engineering methods to build the models and software, while the demand side project used a social science approach. While the projects are distinct, there was an overlap in personnel. Comparing the knowledge extraction, model building, implementation and interface issues of these two deliverables identifies both interesting contrasts and commonalities.