Automation of one-loop corrections for multi-particle processes

With the advent of the Large Hadron Collider, we are in a new era in Particle Physics, in which unprecedented energy scales can be probed. Although it is a discovery machine, it has already been shown to be able to produce experimental precisions at the percent level, and so our theoretical calculations must match that, which requires (at least) calculations to next-to-leading order (NLO). In this thesis, we explain and develop new techniques for the evaluation of one-loop integrals, which have historically been the bottleneck in NLO calculations. After introducing Quantum Field Theory and NLO calculations, we explain the process of tensor reduction and the golem95 method for avoiding its numerical instabilities. We follow this by discussing the techniques used to improve the stability of a library of scalar integrals (for two- and three-point integrals), and then we discuss the extension of the golem95 library to include complex internal masses, along with the reasons for doing so. We then bring together the GoSam project with the event generator Sherpa, in order to calculate the process pp -> e+e−μ+μ− by diboson production to NLO, including the (formally higher order) loop-induced process with gluons in the initial state

Erodibility of hill peat

peer-reviewedThe project was funded by the European Union Structural Funds EAGGF distributed under the Department of Agriculture and Food Stimulus Fund.The energy necessary to entrain soil in water depends on the soil strength. Once entrained, the settling velocity of the eroded soil in water is of fundamental importance to the processes of sediment transport and deposition. In this paper, stream power theory and transport concepts coupled with the equation of continuity were used to derive a transport-limited peat concentration. The ratio of the log of the actual sediment concentration in surface run-off to the log of the transport-limited sediment concentration was the index of erosion used. The value of this index is a measure of the sensitivity of peat to erosion by sheet flow. Four peats were subjected to a range of overland flow rates under two slopes in a laboratory flume. The peats represented peat farmed in a sustainable manner (Leenane), overgrazed peat (Maam), peat undergoing erosion (Newport) and peat which had undergone weathering following exposure by a landslip (Croagh Patrick). Both in situ and surface damaged slabs were studied. The results indicate that shearing and remoulding of a wet peat surface (e.g., by animal treading) and weathering of exposed drained peat surfaces predispose peat to erosion. Defoliation by overgrazing is considered to be of secondary importance.Department of Agriculture, Food and the MarineEuropean Union Structural Funds EAGG

Motivi u osnovi rekreacijske konzumacije alkohola i kanabisa

The Newcastle Substance Use Questionnaire (NSUQ) Motive section is developed based on a novel theoretical background which is instrumental motives. This study aimed to investigate the latent factor structure of the motives of alcohol and cannabis use. There were 285 participants completing the NSUQ-Alcohol, while 62 of them also answered the NSUQ-Cannabis. Exploratory factor analysis (EFA) was performed through FACTOR version 9.2. The NSUQ-Alcohol motives consisted of 14 items. Three-factor model was retained: the social factor explained the largest variance (3.28), being followed by the perspective taking (3.13) and lastly, the sexual motive (1.85). The NSUQ-Cannabis motives comprised of 16 items which was divided also into three factors. The perspective taking factor contributed the most variance (2.72), being followed by the social motive factor (2.47) and the physical motive factor (1.05). These factors may reflect motives of students consuming alcohol and cannabis recreationally.Sekcija ”motivi” koja je dio Newcastle upitnika o upotrebi supstanci (NSUQ) razvijena je na novoj teorijskoj osnovi instrumentalnih motiva. Cilj ovog istraživanja je bio istražiti latentnu strukturu faktora motiva upotrebe alkohola i kanabisa. NSUQ-Alkohol je ispunilo 285 sudionika, dok je njih 62 također ispunilo NSUQ-Cannabis. Eksplorativna faktorska analiza (EFA) učinjena je programom FACTOR, verzija 9.2. Sekcija motivi NSUQ-Alkohol sastojala se od 14 predmeta. Zadržan je trofaktorski model: socijalni faktor objašnjava najveću varijancu (3,28), potom zauzimanje perspektive (3,13) te na kraju seksualni motiv (1,85). Motivi NSUQ-kanabis sastojali su se od 16 predmeta koji su također podijeljeni u tri faktora. Faktor zauzimanja perspektive doprinio je najvećoj varijansi (2,72), a potom ga slijedi faktor socijalnog motiva (2,47) te faktor fizičkog motiva (1,05). Navedeni čimbenici potencijalno odražavaju motive učenika koji rekreativno konzumiraju alkohol i kanabis

"Taking away the chaos": a health needs assessment for people who inject drugs in public places in Glasgow, Scotland

Background: Public injecting of recreational drugs has been documented in a number of cities worldwide and was a key risk factor in a HIV outbreak in Glasgow, Scotland during 2015. We investigated the characteristics and health needs of people involved in this practice and explored stakeholder attitudes to new harm reduction interventions. Methods: We used a tripartite health needs assessment framework, comprising epidemiological, comparative, and corporate approaches. We undertook an analysis of local and national secondary data sources on drug use; a series of rapid literature reviews; and an engagement exercise with people currently injecting in public places, people in recovery from injecting drug use, and staff from relevant health and social services. Results: Between 400 and 500 individuals are estimated to regularly inject in public places in Glasgow city centre: most experience a combination of profound social vulnerabilities. Priority health needs comprise addictions care; prevention and treatment of blood-borne viruses; other injecting-related infections and injuries; and overdose and drug-related death. Among people with lived experience and staff from relevant health and social care services, there was widespread – though not unanimous – support for the introduction of safer injecting facilities and heroin-assisted treatment services. Conclusions: The environment and context in which drug consumption occurs is a key determinant of harm, and is inextricably linked to upstream social factors. Public injecting therefore requires a multifaceted response. Though evidence-based interventions exist, their implementation internationally is variable: understanding the attitudes of key stakeholders provides important insights into local facilitators and barriers. Following this study, Glasgow plans to establish the world’s first co-located safer injecting facility and heroin-assisted treatment service

Predicting whole genome protein interaction networks from primary sequence data in model and non-model organisms using ENTS

Background The large-scale identification of physical protein-protein interactions (PPIs) is an important step toward understanding how biological networks evolve and generate emergent phenotypes. However, experimental identification of PPIs is a laborious and error-prone process, and current methods of PPI prediction tend to be highly conservative or require large amounts of functional data that may not be available for newly-sequenced organisms. Results In this study we demonstrate a random-forest based technique, ENTS, for the computational prediction of protein-protein interactions based only on primary sequence data. Our approach is able to efficiently predict interactions on a whole-genome scale for any eukaryotic organism, using pairwise combinations of conserved domains and predicted subcellular localization of proteins as input features. We present the first predicted interactome for the forest tree Populus trichocarpa in addition to the predicted interactomes for Saccharomyces cerevisiae, Homo sapiens, Mus musculus, and Arabidopsis thaliana. Comparing our approach to other PPI predictors, we find that ENTS performs comparably to or better than a number of existing approaches, including several that utilize a variety of functional information for their predictions. We also find that the predicted interactions are biologically meaningful, as indicated by similarity in functional annotations and enrichment of co-expressed genes in public microarray datasets. Furthermore, we demonstrate some of the biological insights that can be gained from these predicted interaction networks. We show that the predicted interactions yield informative groupings of P. trichocarpa metabolic pathways, literature-supported associations among human disease states, and theory-supported insight into the evolutionary dynamics of duplicated genes in paleopolyploid plants. Conclusion We conclude that the ENTS classifier will be a valuable tool for the de novoannotation of genome sequences, providing initial clues about regulatory and metabolic network topology, and revealing relationships that are not immediately obvious from traditional homology-based annotations

Allostery without conformation change: modelling protein dynamics at multiple scales

The original ideas of Cooper and Dryden, that allosteric signalling can be induced between distant binding sites on proteins without any change in mean structural conformation, has proved to be a remarkably prescient insight into the rich structure of protein dynamics. It represents an alternative to the celebrated Monod–Wyman–Changeux mechanism and proposes that modulation of the amplitude of thermal fluctuations around a mean structure, rather than shifts in the structure itself, give rise to allostery in ligand binding. In a complementary approach to experiments on real proteins, here we take a theoretical route to identify the necessary structural components of this mechanism. By reviewing and extending an approach that moves from very coarse-grained to more detailed models, we show that, a fundamental requirement for a body supporting fluctuation-induced allostery is a strongly inhomogeneous elastic modulus. This requirement is reflected in many real proteins, where a good approximation of the elastic structure maps strongly coherent domains onto rigid blocks connected by more flexible interface regions

A DNA REPAIR/PHASE VARIATION REPORTER SYSTEM USING A POLY-GUANINE TRACT IN A NEISSERIA GONORRHOEAE NITROREDUCTASE GENE

Neisseria gonorrhoeae undergoes phase variation to adapt to new environments, increase pathogenesis, and evade the host immune system. This may be due to defects in DNA repair. A reporter system was created to detect phase variation by phenotypic switching from a nitrofuran-sensitive phenotype to a nitrofuran-resistant (NitR) phenotype. Strains were created with poly-guanine tracts from 5 to 12 guanines in the coding region of a nitroreductase gene (nfsB) that would be susceptible to frame-shifting mutations during DNA replication. The minimum number of consecutive guanines needed to observe increased mutation was 5. A strain expressing 7 guanines nfsB possessed nitroreductase activity similar to wild-type and a spontaneous mutation frequency that was increased ~104 fold relative to wild-type. Frame-shifting mutations of strain expressing 8 guanines in nfsB were observed using denaturing gradient gel electrophoresis (DGGE). Future work with the reporter system could lead to new understanding of phase variation and DNA repair

Research priorities relating to the debate on assisted dying: what do we still need to know? : Results of a modified Delphi technique

Objective To identify the main areas of uncertainty and subsequent research priorities to inform the ongoing debate around assisted dying. Design Two-round electronic modified Delphi consultation with experts and interested bodies. Setting and participants 110 groups and individuals interested in the subject of end of life care and/or assisted dying were approached to participate. Respondents included health and social care professionals, researchers, campaigners, patients, and carers predominately based in the UK. In the first round, the respondents were asked to propose high-priority research questions related to the topic of assisted dying. The collected research questions were then de-duplicated and presented to all respondents in a second round in which they could rate each question in terms of importance. Results 24% and 26% of participants responded to the first and second rounds respectively. Respondents suggested 85 unique research questions in the first round. These were grouped by theme and rated in terms of importance in the second round. Emergent themes were: Palliative care/symptom control; patient characteristics, experiences and decisions; families and carers; society and the general public; arguments for and against assisted dying; international experiences /analysis of existing national data; suicide; mental health, psychological and psychosocial considerations; comorbidities; the role of clinicians; environment and external influences; broader topics incorporating assisted dying; and moral, ethical and legal issues. Ten of the 85 proposed questions were rated as being important (≥7/10) by at least 50% of respondents. Conclusions Research questions with the highest levels of consensus were predominately concerned with understanding how and why people make end-of-life decisions, and which factors influence those decisions. Dissemination of these findings alongside a focused examination of the existing literature may be the most effective way to add evidence to the ongoing debate around assisted dying

Point-Focus Concentration Compact Telescoping Array: EESP Option 1 Phase Final Report for Public Release

Orbital ATK, in partnership with Mark ONeill LLC (MOLLC) and SolAero Technologies Corp., has developed a novel solar array platform, PFC-CTA, which provides a significant advance in performance and cost reduction compared to all currently available space solar systems. PFC refers to the Point Focus Concentration of light provided by MOLLCs thin, flat Fresnel optics. These lenses focus light to a point of approximately 100 times the intensity of the ambient light, onto a solar cell of approximately 1/25th the size of the lens. CTA stands for Compact Telescoping Array1, which is the solar array blanket structural platform originally devised by NASA and currently being advanced by Orbital ATK and partners under NASA and AFRL funding to a projected TRL 5+ by late-2018. The NASA Game Changing Development Extreme Environment Solar Power (EESP) Option 1 Phase study has enabled Orbital ATK to generate and refine component designs, perform component level and system performance analyses, and test prototype hardware of the key elements of PFC-CTA, and increased the TRL of PFC-specific technology elements to TRL ~5. Key performance metrics currently projected are as follows: Scalability from 300 kW per wing (AM0); Specific Power > 250 W/kg (BoL, AM0); Stowage Efficiency > 60 kW/m3; 5:1 margin on pointing tolerance vs. capability; >50% launched cost savings; Wide range of operability between Venus and Saturn by active and/or passive thermal management