cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Expression of platelet derived growth factor (PDGF) ligands and receptors in the ovine ovary and effects of PDGFBB on granulosa cell function
Creators: name: Smith, Peter
name: Reader, Karen
name: French, Michelle
name: Hurst, Peter
name: Juengel, Jenny
Publisher: name: AgResearch
Year: 2025
Subjects: classificationCode: 300305
subject: Animal reproduction and breeding

description: Context: While platelet derived growth factors (PDGF) are expressed in the ovary of some species, relatively little is known regarding the potential role that PDGF play in regulating ovarian follicular development.Aims: To determine the effects of PDGF on granulosa cell function from ovine antral follicles and characterise the expression of PDGF ligands and receptors in developing follicles.Methods: The effects of the PDGF ligand PDGFBB on thymidine incorporation and progesterone production of granulosa cells were determined with established bioassays. Expression patterns of PDGF ligands, PDGFA, B, C, D, and receptors, PDGFRA and B, were determined using in situ hybridisation. The more sensitive technique of RT-PCR was used to confirm expression of PDGFRA and B in granulosa cells of antral follicles.Key results: Thymidine incorporation was increased, and progesterone production decreased, from granulosa cells in response to PDGFBB. Oocytes, granulosa cells, thecal layers and corpora lutea expressed at least one PDGF family member. Granulosa cells had faint expression of PDGF receptors, with thecal and luteal tissue also expressing PDGF receptors. Expression of both ligands and receptors was observed in stroma around the follicle.Conclusions: In sheep, ovarian follicles express both PDGF ligands and receptors, and PDGFBB regulated both thymidine incorporation and progesterone production.Implications: In sheep, PDGF was identified as an additional locally produced growth factor that regulates follicular function, stimulating granulosa cell proliferation and inhibiting progesterone production. Future work to better understand the role of the different ligands and receptors at different stages of ovarian follicular development seems warranted.
Properties of Nb\_xTi\_{(1-x)}N thin films deposited on 300 mm silicon wafers for upscaling superconducting digital circuits
Creators: name: Lozano, Daniel Pérez
name: Soulié, Jean-Philippe
name: Hodges, Blake
name: Piao, Xiaoyu
name: O'Neal, Sabine
name: Valente-Feliciano, Anne-Marie
name: Herr, Quentin
name: Tőkei, Zsolt
name: Kim, Min-Soo
name: Herr, Anna
Publisher: name: arXiv
Year: 2023
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Scaling superconducting digital circuits requires fundamental changes in the current material set and fabrication process. The transition to 300 mm wafers and the implementation of advanced lithography are instrumental in facilitating mature CMOS processes, ensuring uniformity, and optimizing the yield. This study explores the properties of NbxTi(1-x)N films fabricated by magnetron DC sputtering on 300 mm Si wafers. As a promising alternative to traditional Nb in device manufacturing, NbxTi(1-x)N offers numerous advantages, including enhanced stability and scalability to smaller dimensions, in both processing and design. As a ternary material, NbxTi(1-x)N allows engineering material parameters by changing deposition conditions. The engineered properties can be used to modulate device parameters through the stack and mitigate failure modes. We report characterization of NbxTi(1-x)N films at less than 2% thickness variability, 2.4% Tc variability and 3% composition variability. The films material properties such as resistivity (140-375 Ωcm) and critical temperature Tc (4.6 K - 14.1 K) are correlated with stoichiometry and morphology of the films. Our results highlight the significant influence of deposition conditions on crystallographic texture along the films and its correlation with Tc.
description: 8 pages 8 figures
title: Grundfragen multimedialen Lehrens und Lernens
title: 5. und 6. Tagung GML² 2007 und GML² 2008 ; 19. - 21. März 2007 / 13. - 14. März 2008 an der Technischen Universität Berlin und an der Freien Universität Berlin
titleType: Subtitle
Creators: name: (:Unkn) Unknown
Publisher: name: Freie Universität Berlin
Year: 2009
Subjects: subject: 300 Sozialwissenschaften::370 Bildung und Erziehung

description: Dem Lernen und Lehren mit Neuen Medien werden in Zeiten der Informationsgesellschaft oft sagenhafte Eigenschaften zugeschrieben: es sei anschaulicher, attraktiver, motivierender, effizienter, kostengünstiger, gehe besser auf den Lernenden ein, steigere den Lernerfolg, orientiere sich mehr an den kognitiven Strukturen von Lernenden etc.. Damit wenigstens einige der genannten Vorteile wirksam werden, sind geeignete didaktische und methodische Modelle und Konzepte unverzichtbar. Hinzu kommen detaillierte Kenntnisse in der Gestaltung von Lernoberflächen, der technischen Realisierung von Lerninhalten, dem Aufbau lernförderlicher Strukturen und Betreuungskonzepte und dem Betrieb von teilweise virtuellen Universitäten. Inwieweit gesteckte Ziele erreicht wurden, ist anhand von Evaluationsmaßnahmen zu ermitteln. Sämtliche Aspekte müssen bereits in die Planung entsprechender Angebote einbezogen werden. Die Tagungsreihe widmet sich ausgewählten Fragestellungen dieses Themenkomplexes, die durch Vorträge ausgewiesener Experten, durch eingereichte Beiträge und durch Diskussionen in Arbeitsgruppen/Tutorials intensiv behandelt werden. Der Schwerpunkt liegt dabei auf den didaktischen und methodischen Konzepten, die im Rahmen multimedialer Lehre zum Einsatz kommen. Zur Präsentation von Beispielszenarien, Projektergebnissen, Best- Practice sowie zum Erfahrungsaustausch sind ebenfalls stets ausreichend Freiräume eingeplant. Als Zielgruppe sehen wir u.a. Interessentinnen und Interessenten, die – vor allem im Raum Berlin/Brandenburg – an Entwicklung und Einsatz von multimedialen Lehrangeboten arbeiten. Besonders angesprochen sind Mitarbeiter und Mitarbeiterinnen in den laufenden BMBF-Förderprojekten im Programm „Neue Medien in der Bildung“ und in Bildungsinitiativen und -projekten zur Gestaltung der Informationsgesellschaft. Eingeladene Hauptvorträge und eingereichte Beiträge haben die GML² 2007 und die GML² 2008 neben einem Tutorial zu Serious Learning und der Verabschiedung von Thesen zu den Grundfragen multimedialer Lehre und Lernens besonders geprägt. Es wurden Vorträge zur Präsentation angenommen aus Themenbereichen wie Lernszenarien, Online-Learning, Methodik und Didaktik von Lernmodulen, Verteilte Kollaboration, Folie und Blended Learning, hybride Lernumgebungen, Mobile Geräte für Blended Learning, Instruktionsdesign, didaktische Modellierungswerkzeuge, Lernplattformen, Knowledge Sharing, Medien in der Softwareausbildung, E-Learning global, Medienverbünde, E-Learning Produktionsprozess, Online-Betreuung, Kommunikation und Neue Medien im Mathematikunterricht. Ein Posterprogramm begleitete die Tagungen. Die Reihenfolge dieses Doppelbandes ist inhaltlich geordnet, in Reihenfolge Konzepten des eLearning über Studien/Projekte zu Werkzeugen.
Transcriptome Analysis of Environmental Pseudomonas Isolates Reveals Mechanisms of Biodegradation of Naphthenic Acid Fraction Compounds (NAFCs) in Oil Sands Tailings
Creators: name: Chegounian, Parisa
name: Flibotte, Stephane
name: Peru, Kerry
name: Headley, John
name: McMartin, Dena
name: Gramlich, Bryne
name: Yadav, Vikramaditya G.
Publisher: name: Multidisciplinary Digital Publishing Institute
Year: 2021

description: Naphthenic acid fraction compounds (NAFCs) are highly recalcitrant constituents of oil sands tailings. Although some microorganisms in the tailings can individually and synergistically metabolize NAFCs, the biochemical mechanisms that underpin these processes are hitherto unknown. To this end, we isolated two microorganisms, Pseudomonas protegens and Pseudomonas putida, from oils sands tailings and analyzed their transcriptomes to shed light on the metabolic processes employed by them to degrade and detoxify NAFCs. We identified 1048, 521 and 1434 genes that are upregulated in P. protegens, P. putida and a 1:1 co-culture of the strains, respectively. We subsequently enumerated the biochemical activities of enriched genes and gene products to reveal the identities of the enzymes that are associated with NAFC degradation. Separately, we analyzed the NAFCs that are degraded by the two pseudomonads and their 1:1 co-culture and determined the composition of the molecules using mass spectrometry. We then compared these molecular formulas to those of the cognate substrates of the enriched enzymes to chart the metabolic network and understand the mechanisms of degradation that are employed by the microbial cultures. Not only does the consortium behave differently than the pure cultures, but our analysis also revealed the mechanisms responsible for accelerated rate of degradation of NAFCs by the co-culture. Our findings provide new directions for engineering or evolving microorganisms and their consortia for degrading NAFCs more stably and aggressively.
The grounded theory method and its uses for political science
Creators: name: Becker, Brittney
Publisher: name: Freie Universität Berlin
Year: 2012
Subjects: subject: Grounded Theory
subject: International Relations
subject: Political Science
subject: FOS: Political science
subject: applicability
subject: 300 Sozialwissenschaften
subject: 300 Sozialwissenschaften::320 Politikwissenschaft
subject: 300 Sozialwissenschaften::320 Politikwissenschaft::327 Internationale Beziehungen

description: Abstract 4 Introduction 4 The Grounded Theory Method 5 GTM and Theory Generation in Political Science 7 Discussion 10 Conclusion 10 References 12
description: Over the past fifty years, Glaser and Strauss's grounded theory method has become an important component of social science methodology. This paper seeks to determine the uses of grounded theory methodology for the field of political science. After giving an overview of the grounded theory method, the criticisms Glaser and Strauss levelled at the field of sociology are examined and their relevance for political science are discussed. The findings show that grounded theory is able to resolve some of the problems of political science methods, such as its over-reliance on theory testing and deductive approaches to theory generation. However, when considering how one could apply grounded theory methodology to a ‘typical’ political science question on regime change, it becomes clear that the theory’s usage is very limited in some sub-fields of the discipline such as international relations. In the field of political science, therefore, grounded theory methodology is clearly not as widely applicable and useful as Glaser and Strauss proclaim.
ОЦЕНКА СТОМАТОЛОГИЧЕСКОГО СОСТОЯНИЯ КАРИЕСА МОЛОЧНЫХ ЗУБОВ ПОД ВОЗДЕЙСТВИЕМ ГОРМОНАЛЬНЫХ ПРЕПАРАТОВ, ПРИМЕНЯЕМЫХ В ПЕРИОД ВЫНАШИВАНИЯ ПЛОДА.
Creators: name: Мирсалихова, Ф.Л
name: Абдиримова, Гулрух
Publisher: name: Zenodo
Year: 2024

description: В этой статье особое внимание уделяется исследованиям и разработкам, направленным на улучшение лечения гипоплазии эмали у детей, вызванной гормональными препаратами во время беременности. В ней представлены меры по выявлению клинико-функциональных особенностей специфического течения заболеваний, связанных с заболеваниями полости рта в современной стоматологии, развивающихся у детей в результате гормональных препаратов при беременности.
A resolution theorem for extriangulated categories with applications to the index
Creators: name: Ogawa, Yasuaki
name: Shah, Amit
Publisher: name: arXiv
Year: 2023
Subjects: subject: K-Theory and Homology (math.KT)
subject: Category Theory (math.CT)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: Primary 18F25, Secondary 18G80, 18E35

description: Quillen's Resolution Theorem in algebraic $K$-theory provides a powerful computational tool for calculating $K$-groups of exact categories. At the level of $K_0$, this result goes back to Grothendieck. In this article, we first establish an extriangulated version of Grothendieck's Resolution Theorem.
 Second, we use this Extriangulated Resolution Theorem to gain new insight into the index theory of triangulated categories. Indeed, we propose an index with respect to an extension-closed subcategory $\mathscr{N}$ of a triangulated category $\mathscr{C}$ and we prove an additivity formula with error term. Our index recovers the index with respect to a contravariantly finite, rigid subcategory $\mathscr{X}$ defined by Jørgensen and the second author, as well as an isomorphism between $K_0^{\mathsf{sp}}(\mathscr{X})$ and the Grothendieck group of a relative extriangulated structure $\mathscr{C}_{R}^{\mathscr{X}}$ on $\mathscr{C}$ when $\mathscr{X}$ is $n$-cluster tilting. In addition, we generalize and enhance some results of Fedele. Our perspective allows us to remove certain restrictions and simplify some arguments.
 Third, as another application of our Extriangulated Resolution Theorem, we show that if $\mathscr{X}$ is $n$-cluster tilting in an abelian category, then the index introduced by Reid gives an isomorphism $K_0(\mathscr{C}_R^{\mathscr{X}}) \cong K_0^{\mathsf{sp}}(\mathscr{X})$.
description: v4: 27 pages; added Lemma 3.7 and some discussion before it
Functional separation in Europe: The Swedish model
Creators: name: Bergström, Ola
Publisher: name: Swinburne
Year: 2024

description: Access problems in Sweden have led the Swedish government to propose a bill of functional separation well ahead of the parallel process in the European Union. The proposed bill is a framework for imposing functional separation on an operator and does not answer, although implies affirmatively, whether functional separation actually should be imposed in Sweden. A related question is if functional separation could lead to a reduction in and help the removal of sector regulation. Structural measures have been used in general competition law to improve competitive conditions and experience can be drawn from this.
Multi-task Learning Approach for Intracranial Hemorrhage Prognosis
Creators: name: Cobo, Miriam
name: del Barrio, Amaia Pérez
name: Fernández-Miranda, Pablo Menéndez
name: Bellón, Pablo Sanz
name: Iglesias, Lara Lloret
name: Silva, Wilson
Publisher: name: arXiv
Year: 2024
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences
subject: I.2

description: Prognosis after intracranial hemorrhage (ICH) is influenced by a complex interplay between imaging and tabular data. Rapid and reliable prognosis are crucial for effective patient stratification and informed treatment decision-making. In this study, we aim to enhance image-based prognosis by learning a robust feature representation shared between prognosis and the clinical and demographic variables most highly correlated with it. Our approach mimics clinical decision-making by reinforcing the model to learn valuable prognostic data embedded in the image. We propose a 3D multi-task image model to predict prognosis, Glasgow Coma Scale and age, improving accuracy and interpretability. Our method outperforms current state-of-the-art baseline image models, and demonstrates superior performance in ICH prognosis compared to four board-certified neuroradiologists using only CT scans as input. We further validate our model with interpretability saliency maps. Code is available at https://github.com/MiriamCobo/MultitaskLearning_ICH_Prognosis.git.
description: 16 pages. Accepted at Machine Learning in Medical Imaging Workshop @ MICCAI 2024 (MLMI2024). This is the submitted manuscript with added link to github repo, funding acknowledgements and authors' names and affiliations. No further post submission improvements or corrections were integrated. Final version not published yet
Edge-dependent anomalous topology in synthetic photonic lattices subject to discrete step walks
Creators: name: Sokhen, Rabih El
name: Gómez-León, Álvaro
name: Adiyatullin, Albert F.
name: Randoux, Stéphane
name: Delplace, Pierre
name: Amo, Alberto
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Anomalous topological phases, where edge states coexist with topologically trivial Chern bands, can only appear in periodically driven lattices. When the driving is smooth and continuous, the bulk-edge correspondence is guaranteed by the existence of a bulk invariant known as the winding number. However, in lattices subject to periodic discrete-step walks the existence of edge states does not only depend on bulk invariants but also on the boundary. This is a consequence of the absence of an intrinsic time-dependence or micromotion in discrete-step walks. We report the observation of edge states and a simultaneous measurement of the bulk invariants in anomalous topological phases in a two-dimensional synthetic photonic lattice subject to discrete-step walks. The lattice is implemented using time multiplexing of light pulses in two coupled fibre rings, in which one of the dimensions displays real space dynamics and the other one is parametric. The presence of edge states is inherent to the periodic driving and depends on the properties of the boundary in the implemented two-band model with zero Chern number. We provide a suitable expression for the topological invariants whose calculation does not rely on micromotion dynamics.
description: 12 pages main text plus 7 pages of apppendix (19 pages total). Published version
STUDY OF SHOOT MULTIPLICATION OF STRAWBERRY (Fragaria ananassa)
Creators: name: Zobayer, Nayem
name: Prodham, Shamsul H.
name: Sikdar, Saif U.
name: Azim, Fazle
name: Ashrafuzzaman, M.
name: Zobayer, Nayem
name: Prodham, Shamsul H.
name: Sikdar, Saif U.
name: Azim, Fazle
name: Ashrafuzzaman, M.
Publisher: name: Unknown
Year: 0
Subjects: subject: Crop Production/Industries
subject: RABI Strawberry-3
subject: Benzyl Adenine
subject: Kinetin
subject: Shoot Formation and Regeneration

description: Effects of different hormonal concentration on multiple shoot formation of RABI Strawberry-3 were studied. Where the explants were runner tips that cultured on MS basal medium supplemented with 6-Benzyl Adenine and Kinetin. The maximum percentage 80% of shoot was obtained from Benzyl Adenine concentrations of 0.5 mg/l and 1.0 mg/l whereas Kinetin concentrations were 1.5 mg/l and 2.0 mg/l separately. More promising result was found by combining two impressive concentrations of each hormone. When MS basal media was supplemented with Kinetin 2.0mg/l + Benzyl Adenin A 0.5 mg/l, Kinetin 1.5 mg/l + Benzyl Adenine 0.5 mg/l and Kinetin 1.5 mg/l + Benzyl Adenine 1.0 mg/l respectively then 100% shoots were obtained.
Giftfrei leben: Gesundheit schützen, Gefahren minimieren
Creators: name: (:Unkn) Unknown
Publisher: name: Deutscher Naturschutzring e. V.
Year: 2023

description: Für 18 untersuchte Stoffe und Stoffgruppen hat das Gesundheitsforschungsprojekt HBM4EU (Europäische Human Biomonitoring Initiative) über fünf Jahre hinweg kritische Belastungen in nahezu allen Bevölkerungsgruppen Europas gefunden. In 14 Prozent der Körper von Kindern und Jugendlichen finden sich Werte, "bei denen gesundheitliche Folgen nicht mehr ausgeschlossen werden können", erläutert Chemikalienexpertin Dr. Marike Kolossa-Gehring vom Umweltbundesamt (UBA). Und im durchschnittlichen mitteleuropäischen Körper lassen sich rund 400 Chemikalien im Blut finden. Phthalat-Weichmacher, Blei, Fluorchemikalien (PFAS), Arsen - die Belastung ist bedenklich hoch. Erfolgen Stoffverbote, lässt sich das mit zeitlichem Abstand in den Daten wiederfinden, dort finden sich dann aber auch die Substanzen, die die Verbotenen ersetzt haben. Im Sinne der menschlichen und auch planetaren Gesundheit muss hier dringend gehandelt werden. Mit einer nachhaltigen Chemikalienproduktion könnte man eine ganze Reihe Schäden abwenden, sagt Kolossa-Gehring. Ein bisschen mehr leben wie unsere Großeltern sei letztlich auch gut für die Erde, denn "es wird kein gesundes Leben geben, wenn unser Planet nicht auch gesund ist." Quelle: www.dnr.de
Engagement and Progression in Open Online 'Micro Lessons': An Analysis of Learners’ Log Data from an Online Learning Platform
Creators: name: Akbar, Fatema
name: Yasseri, Taha
Publisher: name: American University of Bahrain
Year: 2024
Subjects: classificationCode: 390408
subject: Learning analytics

description: With the rise of different forms of online learning platforms and the new ways that people learn in these platforms, new methods of conceptualizing and measuring learning engagement and progression are needed. The availability of large and detailed data about learners’ actions online can provide insight into different aspects of the learning trajectory. This paper (1) highlights micro-lessons as a type of open online learning that is different from other online platforms in its pedagogical approach and affordances, (2) characterizes user interactions with learning resources on a prominent micro-lesson provider, Khan Academy, and (3) constructs and analyzes measures of learning progression based on the theoretical concepts of learners' grit and growth mindsets using log data of over 300,000 users of micro-lessons. The findings indicate that micro-lessons are most used for just-in-time learning (indicated by single-visits to the platform), rather than attempting to get a more holistic educational experience. Learners' performance in terms of time taken and the number of attempts to get to a correct answer in practice exercises indicated learning progress over time. This work lays the groundwork for future research to understand how micro-lessons can cater to different learner motivations and how learners' interactions with micro-lessons fit with their broader learning experience and goals. Future research can also extend this study’s measures of learning progression in other online platforms that do not offer formal assessments.
eTRIKS analytical environment: a practical platform for medical big data analysis
Creators: name: Oehmichen, Axel
Publisher: name: Imperial College London
Year: 2018

description: Personalised medicine and translational research have become sciences driven by Big Data. Healthcare and medical research are generating more and more complex data, encompassing clinical investigations, 'omics, imaging, pharmacokinetics, Next Generation Sequencing and beyond. In addition to traditional collection methods, economical and numerous information sensing IoT devices such as mobile devices, smart sensors, cameras or connected medical devices have created a deluge of data that research institutes and hospitals have difficulties to deal with. While the collection of data is greatly accelerating, improving patient care by developing personalised therapies and new drugs depends increasingly on an organization's ability to rapidly and intelligently leverage complex molecular and clinical data from that variety of large-scale heterogeneous data sources. As a result, the analysis of these datasets has become increasingly computationally expensive and has laid bare the limitations of current systems. From the patient perspective, the advent of electronic medical records coupled with so much personal data being collected have raised concerns about privacy. Many countries have introduced laws to protect people's privacy, however, many of these laws have proven to be less effective in practice. Therefore, along with the capacity to process the humongous amount of medical data, the addition of privacy preserving features to protect patients' privacy has become a necessity. In this thesis, our first contribution is the development a new platform called the eTRIKS Analytical Environment (eAE) as an answer to those needs of analysing and exploring massive amounts of medical data in a privacy preserving fashion with the constraint of enabling the broadest audience, ranging from medical doctors to advanced coders, to easily and intuitively exploit this new resource. We will present the use of location data in the context of public health research, the work done in the context of data privacy for location data and the extension of the eAE to support privacy preserving analytics. Our second contribution is the implementation of new workflows for tranSMART that leverage the eAE and the support of novel life science approaches for features extraction using deep learning models in the context of sleep research. Finally, we demonstrate the universality and extensibility of the architecture to other research domains by proposing a model aiming at the identification of relevant features for characterizing political deception on Twitter.
Enabling the quantification of human stress from physiological responses
Creators: name: Adjei, Tricia Akua Boakyewaa
Publisher: name: Imperial College London
Year: 2019

description: The stress response primes the human body to overcome a challenge or threat, and is governed by the sympathetic (SNS) and parasympathetic nervous systems (PNS). However, there is a great need to objectively identify stress, as overactivation of the SNS is dangerous to health. This PhD aimed to produce a heart rate variability (HRV) based measure of stress, to outperform the state-of-the- art and objectively identify levels of stress. Classification Angle (ClassA), a nonlinear framework based on second-order-difference plots of HRV, was developed to achieve this aim; ClassA produces four metrics, which include measures of SNS and PNS dynamics, and was tested on the HRV of ten males and ten females, exposed to periods of rest and mental (arithmetic) stress. The framework was compared to the state-of-the-art temporal, spectral and nonlinear measures. Only the heart rate of the males produced significant differences (p-value < 0.01) between the HRV from the rest and stress epochs. In contrast, two of the ClassA metrics were able to discern stress in both the males and females, with three-dimensional plots of the ClassA metrics spatially separating the HRV from the rest and stress epochs. The ability of the framework to distinguish between levels of stress was then tested on the cardiac signals of 28 day-surgery patients, recorded before and during surgery. Pain was defined as a stressor, and the ClassA framework produced significant differences between the HRV from the patients who experienced extreme pain, and those who did not. Furthermore, the ClassA framework has proved unique in accounting for sex-differences in the stress response, and in analysing only ten seconds of HRV data, whilst the state-of-the-art require five minutes. The development of the ClassA framework therefore achieves the PhD aim, and is the first step in the creation of a tool to objectively identify stress.
A multi-dataset analysis of the dynamics of Saturn’s magnetic field configuration
Creators: name: Davies, Ewen
Publisher: name: Imperial College London
Year: 2019

description: The planet Saturn is the second largest planet in the solar system. It is a magnetised body, surrounded by a magnetosphere which acts as a cavity within the solar wind. The Cassini spacecraft explored this system for 13 years, from 2004 until 2017, seeking to answer many of the outstanding questions about this unique solar system environment. This thesis examines a small part of the answer to one of those questions: To what extent are the dynamics of Saturn’s magnetosphere driven by internal and external factors? Saturn’s dayside magnetic field azimuthal configuration is found to exhibit a swept-back configuration at dawn and throughout the dayside, until the early afternoon where it becomes swept-forward. This is found to be similar to the Jovian configuration, although with an earlier boundary. The configuration is shown not to vary significantly with Saturn’s seasons, although some variation is shown to exist. This background having been established, transient events in the configuration can be examined. A case study is carried out on a series of orbits that carry the spacecraft through the high latitude pre-dusk region. These orbits are examined for transient changes as a result of solar wind shocks, the arrival of which is modelled by the Michigan Solar Wind Model. Such transients are detected in 2 of 3 cases, suggesting a solar wind influence on the transient behaviour of the field configuration. To study internal influences of the system, a survey of the post-dawn sector is carried out for transient changes in the configuration that would indicate the presence of return flow plasma, resulting from tail reconnection. 33 instances are detected, characterised by field and particle signatures. These events are found to exhibit organisation by planetary period oscillation phase, suggesting a degree of control on tail reconnection by the rotation of the planet.
Efficacy of an exoskeleton-based physical therapy program for non-ambulatory patients during subacute stroke rehabilitation: a randomized controlled trial
Creators: name: Louie, Dennis R.
name: Mortenson, W. Ben
name: Durocher, Melanie
name: Schneeberg, Amy
name: Teasell, Robert
name: Yao, Jennifer
name: Eng, Janice
Publisher: name: BioMed Central
Year: 2021

description: Background Individuals requiring greater physical assistance to practice walking complete fewer steps in physical therapy during subacute stroke rehabilitation. Powered exoskeletons have been developed to allow repetitious overground gait training for individuals with lower limb weakness. The objective of this study was to determine the efficacy of exoskeleton-based physical therapy training during subacute rehabilitation for walking recovery in non-ambulatory patients with stroke. Methods An assessor-blinded randomized controlled trial was conducted at 3 inpatient rehabilitation hospitals. Patients with subacute stroke (< 3 months) who were unable to walk without substantial assistance (Functional Ambulation Category rating of 0 or 1) were randomly assigned to receive exoskeleton-based or standard physical therapy during rehabilitation, until discharge or a maximum of 8 weeks. The experimental protocol replaced 75% of standard physical therapy sessions with individualized exoskeleton-based sessions to increase standing and stepping repetition, with the possibility of weaning off the device. The primary outcome was walking ability, measured using the Functional Ambulation Category. Secondary outcomes were gait speed, distance walked on the 6-Minute Walk Test, days to achieve unassisted gait, lower extremity motor function (Fugl-Meyer Assessment), Berg Balance Scale, Patient Health Questionnaire, Montreal Cognitive Assessment, and 36-Item Short Form Survey, measured post-intervention and after 6 months. Results Thirty-six patients with stroke (mean 39 days post-stroke) were randomized (Exoskeleton = 19, Usual Care = 17). On intention-to-treat analysis, no significant between-group differences were found in the primary or secondary outcomes at post-intervention or after 6 months. Five participants randomized to the Exoskeleton group did not receive the protocol as planned and thus exploratory as-treated and per-protocol analyses were undertaken. The as-treated analysis found that those adhering to exoskeleton-based physical therapy regained independent walking earlier (p = 0.03) and had greater gait speed (p = 0.04) and 6MWT (p = 0.03) at 6 months; however, these differences were not significant in the per-protocol analysis. No serious adverse events were reported. Conclusions This study found that exoskeleton-based physical therapy does not result in greater improvements in walking independence than standard care but can be safely administered at no detriment to patient outcomes. Clinical Trial Registration The Exoskeleton for post-Stroke Recovery of Ambulation (ExStRA) trial was registered at ClinicalTrials.gov (NCT02995265, first registered: December 16, 2016)
Axion minicluster streams in the solar neighbourhood
Creators: name: O'Hare, Ciaran A. J.
name: Pierobon, Giovanni
name: Redondo, Javier
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: A consequence of QCD axion dark matter being born after inflation is the emergence of small-scale substructures known as miniclusters. Although miniclusters merge to form minihalos, this intrinsic granularity is expected to remain imprinted on small scales in our galaxy, leading to potentially damaging consequences for the campaign to detect axions directly on Earth. This picture, however, is modified when one takes into account the fact that encounters with stars will tidally strip mass from the miniclusters, creating pc-long tidal streams that act to refill the dark matter distribution. Here we ask whether or not this stripping rescues experimental prospects from the worst-case scenario in which the majority of axions remain bound up in unobservably small miniclusters. We find that the density sampled by terrestrial experiment on mpc-scales will be, on average, around 70--90\% of the average local DM density, and at a typical point in the solar neighbourhood, we expect most of the dark matter to be comprised of debris from $\mathcal{O}(10^2$--$10^3)$ overlapping streams. If haloscopes can measure the axion signal with high-enough frequency resolution, then these streams are revealed in the form of an intrinsically spiky lineshape, in stark contrast with the standard assumption of a smooth, featureless Maxwellian distribution -- a unique prediction that constitutes a way for experiments to distinguish between pre and post-inflationary axion cosmologies.
description: 5 + 9 pages, matches journal version
Structural health monitoring of composite patch repair
Creators: name: Lambinet, Florian P. M.
Publisher: name: Imperial College London
Year: 2019

description: This thesis addresses the challenge of composite patch repair of primary structures by proposing structural health monitoring (SHM) solutions to monitor the integrity of the bondline. Two smart repair solutions were investigated with three different sensor technologies. In order to facilitate the data acquisition of multiple sensor devices, a software architecture was developed and a hardware/software solution was designed for Lamb waves acquisition. This data acquisition system proved to be successful in recording Lamb waves in complex scenarios. The first smart re- pair relies on piezoelectric transducers (PZTs) only and was developed throughout different composite repairs of increasing structural complexity. In particular, the final design was a composite step-sanded repair equipped with ten transducers us- ing Lamb waves for damage detection. A novel damage detection and localisation algorithm has been developed and was especially designed to take into account the complexity of composite patch repair. The approach called Minimal Intersection Score (MIS) is based on the first wave packet difference between pristine and dam- age signals of different transmitter-receiver (T-R) pairs intersections in a sparse array. Its effectiveness has been experimentally validated on the smart repair with impact detection under environmental conditions. This algorithm proved to be very robust against temperature. The second smart repair solution uses PZTs and Fiber Bragg Gratings (FBG) and has two different damage detection techniques at its dis- posal: strain sensing or hybrid PZT-FBG guided waves. Firstly, the applicability of an hybrid diagnostic system was demonstrated for detecting an artificial damage at a skin/stiffener interface of a thick composite structure. Then, a hybrid smart repair was manufactured with five PZTs and five FBGs embedded in the bondline of the repair’s top ply. The damage detection efficiency of such hybrid repair was inves- tigated and presented under temperature variations. A novel calibration procedure was designed to take into account the FBG reflectivity changes due to temperature that causes amplitude scaling issues for hybrid Lamb waves measurements. Finally, this calibration method efficiency was experimentally validated by enhancing the impact damage detection capabilities of the hybrid smart repair under temperature variations.
Book review: Protecting good names in cyberspace
Creators: name: Gerrand, Peter
Publisher: name: Swinburne
Year: 2024

description: Review of David Lindsay, International Domain Name Law: ICANN and the UDRP. (Hart Publishing: Oxford and Portland, Oregon, 2007, 512 pp. Hardback, RRP £95/€145/AUD206. ISBN 9781841135847).
Error estimation of different schemes to measure spin-squeezing inequalities
Creators: name: Bönsel, Jan Lennart
name: Imai, Satoya
name: Liu, Ye-Chao
name: Gühne, Otfried
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: How can we analyze quantum correlations in large and noisy systems without quantum state tomography? An established method is to measure total angular momenta and employ the so-called spin-squeezing inequalities based on their expectations and variances. This allows detection of metrologically useful entanglement, but efficient strategies for estimating such nonlinear quantities have yet to be determined. In this paper we show that spin-squeezing inequalities can not only be evaluated by measurements of the total angular momentum but also by two-qubit correlations, either involving all pair correlations or randomly chosen pair correlations. Then we analyze the estimation errors of our approaches in terms of a hypothesis test. For this purpose, we discuss how error bounds can be derived for nonlinear estimators with the help of their variances, characterizing the probability of falsely detecting a separable state as entangled. We focus on the spin-squeezing inequalities in multiqubit systems. Our methods, however, can also be applied to spin-squeezing inequalities for qudits or for the statistical treatment of other nonlinear parameters of quantum states.
description: 22 pages, 9 figures
Gravitational form factor $D$ of charmonium from shear stress
Creators: name: Hu, Tianyang
name: Cao, Xianghui
name: Xu, Siqi
name: Li, Yang
name: Zhao, Xingbo
name: Vary, James P.
Publisher: name: arXiv
Year: 2024
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Based on our recent analysis of the hadronic matrix element of the stress-energy tensor in covariant light front dynamics, we extract the charmonium gravitational form factor $D(Q^2)$ from shear stress $T^{12}$. This is in contrast to our recent work using the (light-front) energy density $T^{+-}$. Indeed, by comparing these two currents, we identify terms that are responsible for the violation of the current conservation. Numerical results based on basis light-front quantization show that the violation effects are small and the $D$-term extracted from the two currents are close to each other, hence validating our previous work using $T^{+-}$.
description: 9 pages, 4 figures, published in Phys. Rev. D
A Melnikov analysis on a family of second order discontinuous differential equations
Creators: name: Novaes, Douglas D.
name: Silva, Luan V. M. F.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 34A36, 34C15, 34C25, 37G15

description: This paper aims to provide a Melnikov-like function that governs the existence of periodic solutions bifurcating from period annuli in certain families of second-order discontinuous differential equations of the form $\ddot{x}+α\; \textrm{sign}(x)=ηx+\varepsilon \;f(t,x,\dot{x})$. This family has attracted considerable attention from researchers, particularly in the analysis of specific instances of $f(t,x,\dot{x})$. The study of this type of differential equation is motivated by its significance in modeling systems with abrupt state changes, both in natural and engineering contexts.
Exploring challenges and opportunities in meeting late-stage end TB goals: Taiwan as a case study
Creators: name: Fu, Han
Publisher: name: Imperial College London
Year: 2019

description: Tuberculosis (TB) in intermediate-burden settings presents an annual incidence rate between 10 and 100 per 100,000 population, with burden concentrating in older adults. Although these settings do not comprise a major part of global TB burden, understanding their epidemics can cast light on priorities for TB elimination elsewhere. In this thesis, using Taiwan as a country example, I apply mathematical models to explore the opportunities and challenges for TB control in such settings. I first evaluate a current policy question about discontinuing universal Bacillus Calmette-Guerin vaccination in Taiwan, considering the vaccine benefits and side-effects. The analysis shows that a substantial cost reduction would occur following the discontinuation, while an uncertain net health impact would result from different assumptions of vaccine protection. Next, I explore the mechanisms driving a notable feature of the TB epidemic - the concentrated burden in the elderly. A combination effect of ‘immune senescence’, ’declining transmission’, and ’age-specific assortativity’ is most likely to explain the wide age disparities, as well as the declining trend of TB burden. I also discuss further evidence for characterising these mechanisms. In collaboration with the Taiwan TB programme, I incorporate key risk structures of TB and compare the impacts of potential strategies for meeting the End TB goals. Model projections reveal a limited effect of active case-finding but great potential of preventive therapy in reducing TB burden, with incremental contribution from glycaemic control. Additionally, critical determinants of the epidemiological impacts are evaluated. Overall, in the intermediate-burden settings like Taiwan, ageing trend will present considerable challenges in achieving TB elimination. Consequently, control strategies which address remote infection in elders will be increasingly crucial. Learnings from this thesis can be useful in strategic planning for other countries approaching similar conditions of TB burden. Meanwhile, uncertainties in TB epidemiology and interventions need further assessment.
A butyrolactone derivative from marine-derived fungal strain Aspergillus terreus BTBU20211037
Creators: name: Zhang, Xinwan
name: Jia, Renming
name: Yang, Jinpeng
name: Song, Zhijun
name: Xu, Xiuli
name: Song, Fuhang
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Biochemistry
subject: Microbiology
subject: FOS: Biological sciences
subject: Pharmacology
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: Biological Sciences not elsewhere classified
subject: Inorganic Chemistry
subject: FOS: Chemical sciences
subject: Infectious Diseases
subject: FOS: Health sciences
subject: Virology

description: The secondary metabolites of marine-derived fungal strain, Aspergillus terreus BTBU20211037, isolated from Qinhuangdao coast were investigated. Thirteen compounds were isolated and identified, including one new compound, butyrolactone J (1), and twelve known compounds, butyrolactone I (2), butyrolactone VI (3), aspernolide B (4), aspernolide A (5), 7’-hydroxybutyrolactone III (6), methyl asterrate (7), methyl dichloroasterrate (8), sulochrin (9), methyl 6-acetyl-4-methoxy-5,7,8-trihydroxynaphthalene-2-carboxylate (10), serantrypinone (11), alantrypinone (12), and territrem A (13). The structures of the compounds were elucidated by HRESIMS, NMR, and ECD analysis. Compounds 1, 10, and 13 showed inhibitory effects against Staphylococcus aureus ATCC 25923 with minimal inhibitory concentrations of 12.5, 25, and 100 μg/mL, respectively.
Fast and adaptive monitor placement for efficient fault localization in large-scale wireless sensor networks
Creators: name: Lins Bezerra, Pamela Thays
Publisher: name: Imperial College London
Year: 2019

description: The recent popularity of different Internet of Things (IoT) applications, such as Digital Twins and Precision Agriculture, has led to the development of different devices and wireless communications protocols to support the deployment of Wireless Sensor Networks (WSN). Unfortunately, WSNs are fault-prone systems, consisting of resource-constrained devices, and unreliable wireless communication links. Additionally, these devices are regularly exposed to the physical world, making WSN more vulnerable to malicious attacks, interference, and physical damage compared to other non-wireless networked systems. Identifying and localizing faults in WSN is relevant for the correct operation of these systems. However, it is a challenging task, and, therefore, there is a growing effort to develop effective fault localization methods. Network tomography, the act of observing end-to-end in-network properties through special nodes known as monitors, is an emerging approach to localize faults in such networks. This non-intrusive solution can be applied to different applications without requiring knowledge of the underlying system. The efficiency of this method depends on the number and position of the monitors, with recent research proposing algorithms to optimize the monitor placement while accurately localizing a number \emph{k} of simultaneous faults. The state-of-the-art solution solves this problem using a greedy heuristic named maximum node-identifiability monitor placement (MNMP). Initial experiments with different networks show, however, that this approach is too slow and does not scale for large systems. This thesis develops solutions to make MNMP fast and adaptable to the topology changes common to WSN. For the fast computation of the monitor placement, we propose schemes for both reducing the size of the network analyzed and the number of redundant operations. For adapting this placement to topology changes, we develop strategies to minimize the search for new monitors by only analyzing the areas of interest. Our experiments show that our fast algorithms compute the best monitor placement 100x faster than MNMP, while the adaptive algorithm adjusts the initial monitor set 1000x more quickly.
On the periodic and antiperiodic aspects of the Floquet normal form
Creators: name: Novaes, Douglas D.
name: Pereira, Pedro C. C. R.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: 34A30, 37C27

description: Floquet's Theorem is a celebrated result in the theory of ordinary differential equations. Essentially, the theorem states that, when studying a linear differential system with $T$-periodic coefficients, we can apply a, possibly complex, $T$-periodic change of variables that transforms it into a linear system with constant coefficients. In this paper, we explore further the question of the nature of this change of variables. We state necessary and sufficient conditions for it to be real and $T$-periodic. Failing those conditions, we prove that we can still find a real change of variables that is "partially" $T$-periodic and "partially" $T$-antiperiodic. We also present applications of this new form of Floquet's Theorem to the study of the behavior of solutions of nonlinear differential systems near periodic orbits.