cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Histone Methylation Patterns in Astrocytes are Influenced by Age Following Ischemia
Creators: name: Nioka C Chisholm
name: Henderson, Michael L
name: Amutha Selvamani
name: Park, Min Jung
name: Dindot, Scott
name: Miranda, Rajesh C
name: Sohrabji, Farida
Publisher: name: Taylor & Francis
Year: 2015
Subjects: subject: 111714 Mental Health
subject: FOS: Health sciences
subject: Developmental Biology
subject: Earth and Environmental Sciences
subject: Physiology
subject: FOS: Biological sciences
subject: Neuroscience
subject: Molecular Biology
subject: Genetics
subject: Cell Biology
subject: Biochemistry

description: In animal models, middle-aged females sustain greater ischemia-induced infarction as compared to adult females. This age difference in infarct severity is associated with reduced functional capacity of astrocytes, a critical neural support cell. The impaired response of astrocytes following stroke in middle-aged females may be related to epigenetic alterations, including histone acetylation or methylation. The present study measured the activity of enzymes that regulate histone acetylation and methylation in cerebral cortical astrocytes of adult (6 month) and middle-aged (11+ month) female rats 48 h following middle cerebral artery occlusion. H3K4 histone methyltransferase activity was decreased in astrocytes from middle-aged females. The next experiment therefore examined H3K4me3 (transcriptional enhancer) and H3K9me3 (transcriptional repressor) in astrocytes from adult and middle-aged females using ChIP-seq analysis. Adult females had more enriched H3K4me3 peaks (304 vs. 26) at transcriptional start sites and fewer H3K9me3 enriched peaks than middle-aged females (4 vs. 22), indicating a pattern of less active chromatin in astrocytes in the older group following ischemia. DAVID clustering analysis of H3K4me3 enriched genes found several functional categories, including cell motility, regulation of apoptosis and the vascular endothelial growth factor (VEGF) pathway. H3K4me3 was enriched at the mir17-20 cluster and VEGFa, and analysis of a separate set of astrocytes confirmed that VEGF protein expression and mir20 mRNA expression were significantly greater following ischemia in adult females compared to middle-aged females. These data indicate that astrocytes display less active chromatin with aging and provide new insight into possible mechanisms for differences in stroke severity observed during aging.
DNA methylation analysis of Homeobox genes implicates HOXB7 hypomethylation as risk factor for neural tube defects
Creators: name: Rochtus, Anne
name: Izzi, Benedetta
name: Vangeel, Elise
name: Louwette, Sophie
name: Wittevrongel, Christine
name: Lambrechts, Diether
name: Moreau, Yves
name: Raf Winand
name: Verpoorten, Carla
name: Jansen, Katrien
name: Geet, Chris Van
name: Freson, Kathleen
Publisher: name: Taylor & Francis
Year: 2015
Subjects: subject: Science Policy
subject: Developmental Biology
subject: Molecular Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Cell Biology

description: Neural tube defects (NTDs) are common birth defects of complex etiology. Though family- and population-based studies have confirmed a genetic component, the responsible genes for NTDs are still largely unknown. Based on the hypothesis that folic acid prevents NTDs by stimulating methylation reactions, epigenetic factors, such as DNA methylation, are predicted to be involved in NTDs. Homeobox (HOX) genes play a role in spinal cord development and are tightly regulated in a spatiotemporal and collinear manner, partly by epigenetic modifications. We have quantified DNA methylation for the different HOX genes by subtracting values from a genome-wide methylation analysis using leukocyte DNA from 10 myelomeningocele (MMC) patients and 6 healthy controls. From the 1575 CpGs profiled for the 4 HOX clusters, 26 CpGs were differentially methylated (P-value < 0.05; β-difference > 0.05) between MMC patients and controls. Seventy-seven percent of these CpGs were located in the HOXA and HOXB clusters, with the most profound difference for 3 CpGs within the HOXB7 gene body. A validation case-control study including 83 MMC patients and 30 unrelated healthy controls confirmed a significant association between MMC and HOXB7 hypomethylation (-14.4%; 95% CI: 11.9-16.9%; P-value < 0.0001) independent of the MTFHR 667C>T genotype. Significant HOXB7 hypomethylation was also present in 12 unaffected siblings, each related to a MMC patient, suggestive of an epigenetic change induced by the mother. The inclusion of a neural tube formation model using zebrafish showed that Hoxb7a overexpression but not depletion resulted in deformed body axes with dysmorphic neural tube formation. Our results implicate HOXB7 hypomethylation as risk factor for NTDs and highlight the importance for future genome-wide DNA methylation analyses without preselecting candidate pathways.
EMPHASIS-PREP Deliverable 2.2: Criteria list for user demands in different access modes
Creators: name: Janni, Michela
name: Moscatelli, Silvana
name: Ceriotti, Aldo
name: Loreto, Francesco
Publisher: name: Zenodo
Year: 2019
Subjects: Plant Phenotyping, Plant phenomics, Research Infrastructure, European research infrastructure

description: Executive Summary Objectives In its preparatory phase (EMPHASIS-PREP), the EMPHASIS project will develop a long-term sustainable strategy for the user-driven building, upgrading and operation of plant phenotyping infrastructures. This deliverable deals with the definition of a criteria list to describe user demand with respect to EMPHASIS plant phenotyping infrastructures (RIs) and resulting services as well as different access modes to infrastructure and services. A criteria list for user demand is functional to the description of users requesting access to EMPHASIS infrastructures and services, and of the scopes for which access is requested. The deliverable is essential to provide concrete benefits to the community, and to help shaping the EMPHASIS-PREP catalogue of services. The criteria list was developed after analysing the result of the EMPHASIS survey launched in 2018 by WP3 and WP2, concerning the mapping of users, of user demand and of the different access mode. This information was then matched with the list of infrastructures previously identified in deliverable 2.1, elaborated by WP2. Main Results The data collected by the 2018 survey “Do you need plant phenotyping?” were analysed to identify: a) the users involved/interested in EMPHASIS, b) their demands, and c) their expectations and needs towards EMPHASIS. A large fraction of the participants in the survey were from the scientific community, which showed to be highly interested in the phenotyping opportunities offered by EMPHASIS-PREP. Twenty percent of the participants were from private companies, showing rising industrial interest in plant phenotyping. For most of the participants EMPHASIS-PREP should support training in plant phenotyping and the expansion of their research network. In 47% of the cases the request was for access to installations. On the basis of user demand towards the EMPHASIS–PREP infrastructures a criteria list was defined for the following types of access and services: ACCESS: access provision for user community to the phenotyping installations incl.: controlled environment installations, field installations, networks of field sites, modelling. QUALITY: measures to implement quality criteria at research infrastructure, specifically experimental design, standards, sensor calibration etc. DATA MANAGEMENT: approaches enabling data reusability embedded in a relevant data policy. INNOVATION: dissemination and utilization of technology and results from access and use of the phenotyping installations. COMMUNICATION: engaging all relevant stakeholders. TRAINIG: supporting the next generation of plant scientist. EXPERT ADVICE: assessment of the plant phenotyping landscape specifically to funders and decision makers
Optimal Selection for Dissimilar Materials using Adhesive Bonding and Mechanical Joining
Creators: name: MKG Abbas
name: N Sakundarini
name: Kong, Ing
Publisher: name: La Trobe
Year: 2021
Subjects: Uncategorized

description: © Published under licence by IOP Publishing Ltd. In the present study, an investigation of double lap joints using two different joining methods was carried out. Carbon fiber and glass fiber reinforced materials were the composite materials that joined with the conventional steel and aluminium. Adhesive bonding joint and a combination of adhesive and mechanical fastener joints were used as a joining approach. It is found that adhesive bonding joint provided a better performance compared to the hybrid joint, where the holes created in the specimens for inserting mechanical fasteners caused a lower strength. It is observed that the adhesive joining of the glass fiber and steel obtained a maximum load of 35.5 KN, which is the highest strength among all other combinations examined in this study, while the similar combination joined using adhesive bonding and mechanical fastener showed a maximum load less than the adhesive joining by 21.4 %.
Latent Surface Models for Networks Using Aggregated Relational Data
Creators: name: McCormick, Tyler H.
name: Zheng, Tian
Publisher: name: Taylor & Francis
Year: 2014
Subjects: subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Science Policy

description: Despite increased interest across a range of scientific applications in modeling and understanding social network structure, collecting complete network data remains logistically and financially challenging, especially in the social sciences. This article introduces a latent surface representation of social network structure for partially observed network data. We derive a multivariate measure of expected (latent) distance between an observed actor and unobserved actors with given features. We also draw novel parallels between our work and dependent data in spatial and ecological statistics. We demonstrate the contribution of our model using a random digit-dial telephone survey and a multiyear prospective study of the relationship between network structure and the spread of infectious disease. The model proposed here is related to previous network models which represents high-dimensional structure through a projection to a low-dimensional latent geometric surface-encoding dependence as distance in the space. We develop a latent surface model for cases when complete network data are unavailable. We focus specifically on aggregated relational data (ARD) which measure network structure indirectly by asking respondents how many connections they have with members of a certain subpopulation (e.g., How many individuals do you know who are HIV positive?) and are easily added to existing surveys. Instead of conditioning on the (latent) distance between two members of the network, the latent surface model for ARD conditions on the expected distance between a survey respondent and the center of a subpopulation on a latent manifold surface. A spherical latent surface and angular distance across the sphere’s surface facilitate tractable computation of this expectation. This model estimates relative homogeneity between groups in the population and variation in the propensity for interaction between respondents and group members. The model also estimates features of groups which are difficult to reach using standard surveys (e.g., the homeless). Supplementary materials for this article are available online.
Architecture of Firm Dynamic Capabilities across Inter-Organizational Activities: Explaining Innovativeness in the Context of Nanotechnology
Creators: name: Petricevic, Olga
Publisher: name: Georgia State University
Year: 2013

description: In this dissertation I first develop a theoretical framework that explores different components of dynamic capabilities related to firm?s boundary-spanning linkages across two different types of inter-organizational activities - alliances and networks. I argue that there are four different subsets of dynamic capabilities simultaneously at work: alliance opportunity-sensing, alliance opportunity-seizing, network opportunity-sensing and network opportunity-seizing. Furthermore, I argue that there are significant interaction effects between these distinctive subsets driving the firm?s overall effectiveness in sensing and seizing of novel and innovative external opportunities. In order to explore potential interdependencies and draw distinctions among different dynamic capability subsets I integrate concepts from the two theoretical perspectives that often neglect the emphasis of the other - the dynamic capability view and the social network perspective. I then test the hypothesized relationships in the context of firms actively patenting in nanotechnology. Nanotechnology innovations are multidisciplinary in nature and require search and discovery across multiple inter-organizational, scientific, geographic, industry, or technological domains by a particular firm. The findings offer support for the conceptualizations of dynamic capabilities as consisting of distinct subsets of capabilities for the sensing and the seizing of external new-knowledge opportunities. The findings suggest that firm?s innovativeness in an interdisciplinary scientific field such as nanotechnology is the function of the vector of multi-dimensional dynamic capabilities that are context-specific. Furthermore, the findings also suggest that there are inherent trade-offs embedded in different dimensions of dynamic capabilities when deployed across a wide range of inter-organizational relationships.
Smoothed and Corrected Score Approach to Censored Quantile Regression With Measurement Errors
Creators: name: Yuanshan Wu
name: Yanyuan Ma
name: Guosheng Yin
Publisher: name: Taylor & Francis
Year: 2014
Subjects: subject: Medicine
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics

description: Censored quantile regression is an important alternative to the Cox proportional hazards model in survival analysis. In contrast to the usual central covariate effects, quantile regression can effectively characterize the covariate effects at different quantiles of the survival time. When covariates are measured with errors, it is known that naively treating mismeasured covariates as error-free would result in estimation bias. Under censored quantile regression, we propose smoothed and corrected estimating equations to obtain consistent estimators. We establish consistency and asymptotic normality for the proposed estimators of quantile regression coefficients. Compared with the naive estimator, the proposed method can eliminate the estimation bias under various measurement error distributions and model error distributions. We conduct simulation studies to examine the finite-sample properties of the new method and apply it to a lung cancer study. Supplementary materials for this article are available online.
A matter of trust: how Americans and Australians diverged in trust and media use during a global pandemic
Creators: name: Carson, Andrea
name: Ratcliff, Shaun
name: Ruppanner, Leah
Publisher: name: La Trobe
Year: 2021
Subjects: Uncategorized

description: Recent surveys show media trust is low in Australia and the United States. Less clear is how much media trust matters for citizens’ uses of different types of media and under what conditions (Strömbäck et al., 2020). This article focuses on trust in journalists and other information sources – medical experts and friends and family on social media – during a time of crisis: the COVID-19 pandemic. Using survey data, we measure citizens’ trust in COVID-19 information sources and the implications of media use and partisanship during the health crisis. We find stark differences in media use and trust in journalists between the US and Australia. The US has partisan patterns of media consumption serving different public spheres. Most Republican voters do not trust professional journalists and were less likely to trust medical experts. While, Democrats are more trusting of professional journalists, health experts and turn to mainstream media for COVID-19 information. Republicans, who tended to rely on conservative media for news, were the least concerned about catching coronavirus and most likely to believe restrictions on movement and gatherings had gone too far. In contrast, most Australians, regardless of partisanship, express higher levels of trust in professional journalists and medical experts for COVID-19 information. Differences in media use, trust and partisanship between the two democracies reflect patently different attitudes to government lockdowns. We conclude low trust in professional journalists and medical experts matters; without it, government agency to manage the health crisis is undermined.
Analysis of Longitudinal Multivariate Outcome Data From Couples Cohort Studies: Application to HPV Transmission Dynamics
Creators: name: Xiangrong Kong
name: Wang, Mei-Cheng
name: Gray, Ronald
Publisher: name: Taylor & Francis
Year: 2015
Subjects: subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: Science Policy
subject: Cancer
subject: Mathematics
subject: FOS: Mathematics
subject: Biological Sciences
subject: Biotechnology
subject: Medicine

description: We consider a specific situation of correlated data where multiple outcomes are repeatedly measured on each member of a couple. Such multivariate longitudinal data from couples may exhibit multi-faceted correlations that can be further complicated if there are polygamous partnerships. An example is data from cohort studies on human papillomavirus (HPV) transmission dynamics in heterosexual couples. HPV is a common sexually transmitted disease with 14 known oncogenic types causing anogenital cancers. The binary outcomes on the multiple types measured in couples over time may introduce inter-type, intra-couple, and temporal correlations. Simple analysis using generalized estimating equations or random effects models lacks interpretability and cannot fully use the available information. We developed a hybrid modeling strategy using Markov transition models together with pairwise composite likelihood for analyzing such data. The method can be used to identify risk factors associated with HPV transmission and persistence, estimate difference in risks between male-to-female and female-to-male HPV transmission, compare type-specific transmission risks within couples, and characterize the inter-type and intra-couple associations. Applying the method to HPV couple data collected in a Ugandan male circumcision (MC) trial, we assessed the effect of MC and the role of gender on risks of HPV transmission and persistence. Supplementary materials for this article are available online.
Latent Surface Models for Networks Using Aggregated Relational Data
Creators: name: McCormick, Tyler H.
name: Zheng, Tian
Publisher: name: Taylor & Francis
Year: 2016
Subjects: subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Science Policy

description: Despite increased interest across a range of scientific applications in modeling and understanding social network structure, collecting complete network data remains logistically and financially challenging, especially in the social sciences. This article introduces a latent surface representation of social network structure for partially observed network data. We derive a multivariate measure of expected (latent) distance between an observed actor and unobserved actors with given features. We also draw novel parallels between our work and dependent data in spatial and ecological statistics. We demonstrate the contribution of our model using a random digit-dial telephone survey and a multiyear prospective study of the relationship between network structure and the spread of infectious disease. The model proposed here is related to previous network models which represents high-dimensional structure through a projection to a low-dimensional latent geometric surface-encoding dependence as distance in the space. We develop a latent surface model for cases when complete network data are unavailable. We focus specifically on aggregated relational data (ARD) which measure network structure indirectly by asking respondents how many connections they have with members of a certain subpopulation (e.g., How many individuals do you know who are HIV positive?) and are easily added to existing surveys. Instead of conditioning on the (latent) distance between two members of the network, the latent surface model for ARD conditions on the expected distance between a survey respondent and the center of a subpopulation on a latent manifold surface. A spherical latent surface and angular distance across the sphere’s surface facilitate tractable computation of this expectation. This model estimates relative homogeneity between groups in the population and variation in the propensity for interaction between respondents and group members. The model also estimates features of groups which are difficult to reach using standard surveys (e.g., the homeless). Supplementary materials for this article are available online.
Smoothed and Corrected Score Approach to Censored Quantile Regression With Measurement Errors
Creators: name: Yuanshan Wu
name: Yanyuan Ma
name: Guosheng Yin
Publisher: name: Taylor & Francis
Year: 2016
Subjects: subject: Medicine
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics

description: Censored quantile regression is an important alternative to the Cox proportional hazards model in survival analysis. In contrast to the usual central covariate effects, quantile regression can effectively characterize the covariate effects at different quantiles of the survival time. When covariates are measured with errors, it is known that naively treating mismeasured covariates as error-free would result in estimation bias. Under censored quantile regression, we propose smoothed and corrected estimating equations to obtain consistent estimators. We establish consistency and asymptotic normality for the proposed estimators of quantile regression coefficients. Compared with the naive estimator, the proposed method can eliminate the estimation bias under various measurement error distributions and model error distributions. We conduct simulation studies to examine the finite-sample properties of the new method and apply it to a lung cancer study. Supplementary materials for this article are available online.
Texture evolution in Ti-6AI-4V
Creators: name: Wyatt, Simon James
Publisher: name: Imperial College London
Year: 2019

description: Crystallographic orientation and microstructural morphology control properties in engineering materials. Titanium alloys are used extensively in commercial turbofan aircraft engines, due to their high strength and excellent corrosion resistance. The formation of preferred crystallite orientations during manufacturing must be understood in order to maximise component lifespan and avoid failure. In this thesis, I present a methodology which generates virtual 3D microstructures representing a material, conforming to an approximation of a 2D reference surface characterised by electron backscatter diffraction (EBSD). The subsurface grains of this microstructure are instanced using statistical information taken from the map, controlling grain size and texture. The subsurface texture is controlled through optimisations of an orientation distribution function (ODF) and misorientation distribution function (MDF). The influence of this control is shown through simulating deformation within the DAMASK crystal plasticity fast Fourier transform (CP-FFT) solver, to demonstrate the effect of subsurface texture on the stress and strain partitioning on the reference surface. The textures of Ti-6Al 4V formed through hot-rolling at temperatures between 750 and 950 °C are characterised by EBSD. As this method measures spatial and orientation information describing a 2D surface the material, I investigate the mechanisms through which lattice orientations of crystallites evolve during processing. EBSD maps are segmented by preferred orientation to demonstrate the spatial distribution of texture fibres. By measuring phase composition through direct backscatter spectroscopy (DBS) and elemental composition through energy dispersive x-ray spectroscopy (EDS), I demonstrate the influence of the β phase on the formation of texture fibres during rolling, with weak evolution of all existing texture fibres as the Ti-6Al-4V bar plastically deforms through slip. Through CP-FFT simulations of synthetic textured polycrystals in DAMASK, using the orientations of the texture fibres observed by EBSD, I simulate the texture evolution during deformation by hot rolling. Through examination of lattice rotation, slip shear rates and twinning shear rates, I demonstrate that the texture evolution resulting from plastic deformation at high temperatures is conducted entirely by crystal slip, resulting in only small lattice rotations and weak texture evolution. This is in agreement with the textures obtained through EBSD of hot-rolled Ti-6Al-4V.
Latent surface models for networks using Aggregated Relational Data
Creators: name: Zheng, Tian
name: McCormick, Tyler H.
Publisher: name: Taylor & Francis
Year: 2014
Subjects: subject: Science Policy
subject: Biological Sciences
subject: Ecology
subject: FOS: Biological sciences
subject: Earth and Environmental Sciences

description: Despite increased interest across a range of scientific applications in modeling and understanding social network structure, collecting complete network data remains logistically and financially challenging, especially in the social sciences. This paper introduces a latent surface representation of social network structure for partially observed network data. We derive a multivariate measure of expected (latent) distance between an observed actor and unobserved actors with given features. We also draw novel parallels between our work and dependent data in spatial and ecological statistics. We demonstrate the contribution of our model using a random digit-dial telephone survey and a multiyear prospective study of the relationship between network structure and the spread of infectious disease. The model proposed here is related to previous network models which represents high dimensional structure through a projection to a low-dimensional latent geometric surface—encoding dependence as distance in the space. We develop a latent surface model for cases when complete network data are unavailable. We focus specifically on Aggregated Relational Data (ARD) which measure network structure indirectly by asking respondents how many connections they have with members of a certain subpopulation (e.g. How many individuals do you know who are HIV positive?) and are easily added to existing surveys. Instead of conditioning on the (latent) distance between two members of the network, the latent surface model for ARD conditions on the expected distance between a survey respondent and the center of a subpopulation on a latent manifold surface. A spherical latent surface and angular distance across the sphere’s surface facilitate tractable computation of this expectation. This model estimates relative homogeneity between groups in the population and variation in the propensity for interaction between respondents and group members. The model also estimates features of groups which are difficult to reach using standard surveys (the homeless, for example).
Supporting breastfeeding in local communities (SILC): a cluster randomised controlled trial in Victoria
Creators: name: Forster, Della
name: McLachlan, Helen
name: Amir, Lisa
name: Small, Rhonda
name: Meabh Cullinane
name: L Watson
name: Touran Shafiei
Publisher: name: La Trobe
Year: 2021
Subjects: Uncategorized

description: No description supplied
Smoothed and Corrected Score Approach to Censored Quantile Regression With Measurement Errors
Creators: name: Guosheng Yin
name: Yuanshan Wu
name: Yanyuan Ma
Publisher: name: Taylor & Francis
Year: 2014
Subjects: subject: Mathematics
subject: FOS: Mathematics
subject: Biological Sciences
subject: Earth and Environmental Sciences
subject: Biotechnology
subject: Medicine

description: Censored quantile regression is an important alternative to the Cox proportional hazards model in survival analysis. In contrast to the usual central covariate effects, quantile regression can effectively characterize the covariate effects at different quantiles of the survival time. When covariates are measured with errors, it is known that naively treating mismeasured covariates as error-free would result in estimation bias. Under censored quantile regression, we propose smoothed and corrected estimating equations to obtain consistent estimators. We establish consistency and asymptotic normality for the proposed estimators of quantile regression coefficients. Compared with the naive estimator, the proposed method can eliminate the estimation bias under various measurement error distributions and model error distributions. We conduct simulation studies to examine the finite-sample properties of the new method and apply it to a lung cancer study.
Latent Space Models for Dynamic Networks
Creators: name: Sewell, Daniel K.
name: Yuguo Chen
Publisher: name: Taylor & Francis
Year: 2014
Subjects: subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Computational Biology

description: Dynamic networks are used in a variety of fields to represent the structure and evolution of the relationships between entities. We present a model which embeds longitudinal network data as trajectories in a latent Euclidean space. We propose Markov chain Monte Carlo (MCMC) algorithm to estimate the model parameters and latent positions of the actors in the network. The model yields meaningful visualization of dynamic networks, giving the researcher insight into the evolution and the structure, both local and global, of the network. The model handles directed or undirected edges, easily handles missing edges, and lends itself well to predicting future edges. Further, a novel approach is given to detect and visualize an attracting influence between actors using only the edge information. We use the case-control likelihood approximation to speed up the estimation algorithm, modifying it slightly to account for missing data. We apply the latent space model to data collected from a Dutch classroom, and a cosponsorship network collected on members of the U.S. House of Representatives, illustrating the usefulness of the model by making insights into the networks. Supplementary materials for this article are available online.
The effect of constraint on the fracture toughness of reactor pressure vessel steels
Creators: name: Rait, Geena Kaur
Publisher: name: Imperial College London
Year: 2019

description: Fracture toughness assessments of nuclear pressure vessel (PV) steels are conducted on highly constrained test geometries to ensure a conservative, lower bound prediction of fracture toughness properties. These assessment methods, whilst safe, can result in over conservative predictions of toughness and therefore component life. This research explores the effect of different crack tip constraint conditions on the measured fracture toughness of PV steels. Experimental fracture toughness tests of two deeply notched specimen geometries were conducted on SA508 Grade 3 Class 1 forging steel. These were the single edge notched bend specimen and the single edge notched tension specimen. These samples were tested at a range of temperatures to obtain: the Master Curve reference temperature, T$_0$, and to observe the behaviour of the tension geometry along the ductile to brittle transition. The tests were also modelled using finite element analysis. Subsequent work simulated historical wide plate biaxial fracture toughness tests conducted on A533B plate steel. These geometries were cruciform specimens with through thickness cracks tested in tension for a range of biaxial loading conditions. For all of the simulations conducted, the fracture parameters K and J and the in-plane constraint parameters, T-stress and Q, were obtained in order to provide a description of constraint effects on fracture toughness. Despite a significant amount of scatter evidenced in the fracture toughness results of the SA508 alloy, T$_0$ reference temperatures were determined. These temperatures were representative of the geometrical constraint associated with the geometries tested, for the given material condition. These results indicated that the fracture toughness behaviour of the deeply notched bend and tension specimens were similar for low temperature testing. This was further shown through Q parameter analysis and crack tip plastic zone size evaluation for both geometries. For the biaxial simulations, it was found that an increase in biaxial ratio resulted in reduced predictions of fracture toughness and a corresponding increase in constraint prediction. The highest biaxial ratio considered, indicated a similar level of constraint to the deeply notched bend and tension geometry. A deeply notched bend geometry can therefore still be considered as a suitable, i.e. conservative, specimen in the fracture toughness testing of PV steels.
Assessment and optimisation of wearable activity monitors within an enhanced recovery framework
Creators: name: Abeles, Aliza
Publisher: name: Imperial College London
Year: 2019

description: Enhanced recovery after surgery (ERAS) is a model of care that aims to improve patient recovery after surgery. Wearable activity monitors (WAMs) have the potential to provide possible solutions to a wide range of clinical challenges. The aim of this thesis was to assess whether physical activity, measured by a WAM, can be used as a measurable marker of peri-operative well-being and recovery after surgery, and whether the WAM can therefore be used to assess and help improve recovery after surgery. A wrist-worn WAM was utilised to measure physical activity in a healthy normal cohort showing that it was feasible to monitor continuous physical activity in a healthy cohort in a free-living environment. Activity data were processed both at an individual level and as a group allowing further analysis and comparator with the surgical patient cohort. The WAM was used to measure objective physical activity data for a cohort of patients undergoing colorectal surgery. Activity was assessed pre-operatively at home, post-operatively on the in-patient ward and then on discharge home back into the community. The physical activity data gave insight into patients’ baseline function and their progression and recovery following their surgical procedure, with more detailed analysis showing the WAM’s ability to reflect the daily activities on the ward. There were statistically significant correlations between peri-operative physical activity and post-operative outcomes. The results from the use of WAMs within this thesis provide an opportunity for refining the ERAS concept through continuous, objective physical activity monitoring as well as the potential to enhance patient/clinician communication, leading to more personalised care and an improvement in post-operative outcomes.
Analysis of longitudinal multivariate outcome data from couples cohort studies: application to HPV transmission dynamics
Creators: name: Xiangrong Kong
name: Wang, Mei-Cheng
name: Gray, Ronald
Publisher: name: Taylor & Francis
Year: 2015
Subjects: subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: Science Policy
subject: Cancer
subject: Mathematics
subject: FOS: Mathematics
subject: Biological Sciences
subject: Biotechnology
subject: Medicine

description: We consider a specific situation of correlated data where multiple outcomes are repeatedly measured on each member of a couple. Such multivariate longitudinal data from couples may exhibit multi-faceted correlations which can be further complicated if there are polygamous partnerships. An example is data from cohort studies on human papillomavirus (HPV) transmission dynamics in heterosexual couples. HPV is a common sexually transmitted disease with 14 known oncogenic types causing anogenital cancers. The binary outcomes on the multiple types measured in couples over time may introduce inter-type, intra-couple, and temporal correlations. Simple analysis using generalized estimating equations or random effects models lacks interpretability and cannot fully utilize the available information. We developed a hybrid modeling strategy using Markov transition models together with pairwise composite likelihood for analyzing such data. The method can be used to identify risk factors associated with HPV transmission and persistence, estimate difference in risks between male-to-female and female-to-male HPV transmission, compare type-specific transmission risks within couples, and characterize the inter-type and intra-couple associations. Applying the method to HPV couple data collected in a Ugandan male circumcision (MC) trial, we assessed the effect of MC and the role of gender on risks of HPV transmission and persistence.
Pharmacological inhibition of Polo-like kinase 1 (PLK1) by BI-2536 decreases the viability and survival of hamartin and tuberin deficient cells via induction of apoptosis and attenuation of autophagy
Creators: name: Valianou, Matthildi
name: Cox, Andrew M
name: Pichette, Benjamin
name: Hartley, Shannon
name: Unmesha Roy Paladhi
name: Astrinidis, Aristotelis
Publisher: name: Taylor & Francis
Year: 2015
Subjects: subject: Biophysics
subject: Biochemistry
subject: Medicine
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Pharmacology
subject: Developmental Biology
subject: Cancer
subject: Hematology

description: The mechanistic target of rapamycin complex 1 (mTORC1) increases translation, cell size and angiogenesis, and inhibits autophagy. mTORC1 is negatively regulated by hamartin and tuberin, the protein products of the tumor suppressors TSC1 and TSC2 that are mutated in Tuberous Sclerosis Complex (TSC) and sporadic Lymphangioleiomyomatosis (LAM). Hamartin interacts with the centrosomal and mitotic kinase polo-like kinase 1 (PLK1). Hamartin and tuberin deficient cells have abnormalities in centrosome duplication, mitotic progression, and cytokinesis, suggesting that the hamartin/tuberin heterodimer and mTORC1 signaling are involved in centrosome biology and mitosis. Here we report that PLK1 protein levels are increased in hamartin and tuberin deficient cells and LAM patient-derived specimens, and that this increase is rapamycin-sensitive. Pharmacological inhibition of PLK1 by the small-molecule inhibitor BI-2536 significantly decreased the viability and clonogenic survival of hamartin and tuberin deficient cells, which was associated with increased apoptosis. BI-2536 increased p62, LC3B-I and GFP-LC3 punctae, and inhibited HBSS-induced degradation of p62, suggesting that PLK1 inhibition attenuates autophagy. Finally, PLK1 inhibition repressed the expression and protein levels of key autophagy genes and proteins and the protein levels of Bcl-2 family members, suggesting that PLK1 regulates both autophagic and apoptotic responses. Taken together, our data point toward a previously unrecognized role of PLK1 on the survival of cells with mTORC1 hyperactivation, and the potential use of PLK1 inhibitors as novel therapeutics for tumors with dysregulated mTORC1 signaling, including TSC and LAM.
Pharmacological inhibition of Polo-like kinase 1 (PLK1) by BI-2536 decreases the viability and survival of hamartin and tuberin deficient cells via induction of apoptosis and attenuation of autophagy
Creators: name: Valianou, Matthildi
name: Cox, Andrew M
name: Pichette, Benjamin
name: Hartley, Shannon
name: Unmesha Roy Paladhi
name: Astrinidis, Aristotelis
Publisher: name: Taylor & Francis
Year: 2015
Subjects: subject: Hematology
subject: Cancer
subject: Developmental Biology
subject: Biological Sciences
subject: Chemistry
subject: Pharmacology
subject: Molecular Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Cell Biology
subject: Medicine
subject: Biochemistry
subject: Biophysics

description: The mechanistic target of rapamycin complex 1 (mTORC1) increases translation, cell size and angiogenesis, and inhibits autophagy. mTORC1 is negatively regulated by hamartin and tuberin, the protein products of the tumor suppressors TSC1 and TSC2 that are mutated in Tuberous Sclerosis Complex (TSC) and sporadic Lymphangioleiomyomatosis (LAM). Hamartin interacts with the centrosomal and mitotic kinase polo-like kinase 1 (PLK1). Hamartin and tuberin deficient cells have abnormalities in centrosome duplication, mitotic progression, and cytokinesis, suggesting that the hamartin/tuberin heterodimer and mTORC1 signaling are involved in centrosome biology and mitosis. Here we report that PLK1 protein levels are increased in hamartin and tuberin deficient cells and LAM patient-derived specimens, and that this increase is rapamycin-sensitive. Pharmacological inhibition of PLK1 by the small-molecule inhibitor BI-2536 significantly decreased the viability and clonogenic survival of hamartin and tuberin deficient cells, which was associated with increased apoptosis. BI-2536 increased p62, LC3B-I and GFP-LC3 punctae, and inhibited HBSS-induced degradation of p62, suggesting that PLK1 inhibition attenuates autophagy. Finally, PLK1 inhibition repressed the expression and protein levels of key autophagy genes and proteins and the protein levels of Bcl-2 family members, suggesting that PLK1 regulates both autophagic and apoptotic responses. Taken together, our data point toward a previously unrecognized role of PLK1 on the survival of cells with mTORC1 hyperactivation, and the potential use of PLK1 inhibitors as novel therapeutics for tumors with dysregulated mTORC1 signaling, including TSC and LAM.
Towards a non-equilibrium thermodynamic theory of ecosystem assembly and development
Creators: name: Cook, Jacob
Publisher: name: Imperial College London
Year: 2021

description: Non-equilibrium thermodynamics has had a significant historic influence on the development of theoretical ecology, even informing the very concept of an ecosystem. Much of this influence has manifested as proposed extremal principles. These principles hold that systems will tend to maximise certain thermodynamic quantities, subject to the other constraints they operate under. A particularly notable extremal principle is the maximum entropy production principle (MaxEPP); that systems maximise their rate of entropy production. However, these principles are not robustly based in physical theory, and suffer from treating complex ecosystems in an extremely coarse manner. To address this gap, this thesis derives a limited but physically justified extremal principle, as well as carrying out a detailed investigation of the impact of non-equilibrium thermodynamic constraints on the assembly of microbial communities. The extremal principle we obtain pertains to the switching between states in simple bistable systems, with switching paths that generate more entropy being favoured. Our detailed investigation into microbial communities involved developing a novel thermodynamic microbial community model, using which we found the rate of ecosystem development to be set by the availability of free-energy. Further investigation was carried out using this model, demonstrating the way that trade-offs emerging from fundamental thermodynamic constraints impact the dynamics of assembling microbial communities. Taken together our results demonstrate that theory can be developed from non-equilibrium thermodynamics, that is both ecologically relevant and physically well grounded. We find that broad extremal principles are unlikely to be obtained, absent significant advances in the field of stochastic thermodynamics, limiting their applicability to ecology. However, we find that detailed consideration of the non-equilibrium thermodynamic mechanisms that impact microbial communities can broaden our understanding of their assembly and functioning.
What is the mental health literacy of tertiary students? A systematic review
Creators: name: Johnson, Nicole
name: Anderson, Karen
name: Spong, Jo
name: Hanson, Lisa
name: Wilson, Elena
name: Emond, Katherine
name: Furness, Susan
name: Brown, Christopher
Publisher: name: La Trobe
Year: 2021
Subjects: Uncategorized

description: No description supplied
Is there a moral difference between killing and letting die in healthcare?
Creators: name: Alanazi, Mohammed
Publisher: name: figshare
Year: 2015
Subjects: Health Care

description: The purpose of this review is to prove that there is no moral difference between killing and letting one die in healthcare. It is important to be aware of the moral equivalence of killing and letting die. The doctor that allows the patient to die without providing life saving measures, and the doctor that administers a lethal injection both have the same outcome. The patient dies in either case. The Abrahamic religions; Islam, Christianity, and Judaism, all argue for the sanctity of life. The world’s major religions; Islam, Christianity, and Judaism all have doctrines concerning the sanctity of life; and they support the main arguments of this study that there is no moral difference between killing and letting die. In relation to patient autonomy and the patient's right to die, it is very important to highlight that doctors have a moral and legal responsibility to save lives. In addition, we discuss the distinction centres on the true definition of patient autonomy, and who is responsible for defining the “quality” of life. The intention and foresight are critical points that support the thesis statement that killing and letting one die are one in the same. Intention is the intentional killing of a human being, however, the when one refers to foreseen, it brings to mind images of a doctor and a patient’s family that is taking into consideration the entire different variables that they must deal with in order to decide whether or not to terminate life sustaining measures. They are trying to foresee what type of life the patient will have if life prolonging treatment is withdrawn. The acts and omissions doctrine as described in this review shows that there is no moral difference to kill a person or to let him die. The end result is the same, and someone is dead. Finally, we extensively discussed the various viewpoints regarding whether or not there is a moral difference between killing and letting die. The evidence reveals that there is no moral difference between the two. There is no doubt that the debate over killing and letting die will continue for years to come. It is critical that the issue be addressed at this particular time in history with the advent of modern medical technology.