cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Advancing the Understanding of Multiple Long-Term Conditions through AI and Open Science: The AIM Research Support Facility
Creators: name: Almarzouq, Batool
Publisher: name: Zenodo
Year: 2023

description: Multiple Long-Term Conditions (MLTC) are a significant health challenge affecting an estimated 14 million people in England alone. As Artificial Intelligence (AI) becomes increasingly relevant to healthcare, researchers are working to better understand how complex disease patterns, treatment pathways, and socioeconomic factors influence patient outcomes. The AI for Multiple Long-Term Conditions (AIM) programme comprises from seven consortia across the UK. The AIM Research Support Facility (RSF) at the Alan Turing Institute, in collaboration with Edinburgh and Swansea universities, supports the secen consortia in prioritising collaborative development, reproducibility, interoperability, and public engagement. The RSF plays a crucial role in ensuring that datasets are properly aligned, FAIR and standardized, supporting the reuse of research artefacts and outputs for extended analyses within the AIM programme and beyond. Through hands-on workshops, ECR lunchtime sessions, and collaboration cafes, the programme fosters connections between researchers, clinicians, policymakers, and the public to create a supportive research environment that drives scientific progress in healthcare research that focuses on open science principles. This lightning talk invites researchers, clinicians, policymakers, and the public to learn about the revolutionary work being done by the AIM RSF programme. We will showcase how collaborative development, reproducibility, interoperability, and public engagement are integral to our approach to advancing the understanding of MLTC. Our collaborations are breaking new ground in the field of health and care through an emphasis on open science principles and inclusive collaboration.
description: This poster was presented during the 4th Open Science Fair (25-27 September, Madrid, Spain).
Dynamics of a population of oscillatory and excitable elements
Creators: name: O'Keeffe, Kevin P.
name: Strogatz, Steven H.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: We analyze a variant of a model proposed by Kuramoto, Shinomoto, and Sakaguchi for a large population of coupled oscillatory and excitable elements. Using the Ott-Antonsen ansatz, we reduce the behavior of the population to a two-dimensional dynamical system with three parameters. We present the stability diagram and calculate several of its bifurcation curves analytically, for both excitatory and inhibitory coupling. Our main result is that when the coupling function is broad, the system can display bistability between steady states of constant high and low activity, whereas when the coupling function is narrow and inhibitory, one of the states in the bistable regime can show persistent pulsations in activity.
Table S1 from Top-down response to spatial variation in productivity and bottom-up response to temporal variation in productivity in a long-term study of desert ants
Creators: name: Gibb, Heloise
name: Wardle, Glenda M.
name: Greenville, Aaron C.
name: Grossman, Blair F.
name: Dickman, Chris R.
Publisher: name: The Royal Society
Year: 2022
Subjects: subject: Ecology
subject: FOS: Biological sciences

description: AIC values for models with and without the interaction between spatial and temporal variation in productivity (Long-term precipitation x Landscape position). Models within 2 AIC of the best model are in bold text. Models without the interaction term are shown below.
Di-photon excess illuminates Dark Matter
Creators: name: Backovic, Mihailo
name: Mariotti, Alberto
name: Redigolo, Diego
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We propose a simplified model of dark matter with a scalar mediator to accommodate the di-photon excess recently observed by the ATLAS and CMS collaborations. Decays of the resonance into dark matter can easily account for a relatively large width of the scalar resonance, while the magnitude of the total width combined with the constraint on dark matter relic density lead to sharp predictions on the parameters of the Dark Sector. Under the assumption of a rather large width, the model predicts a signal consistent with ~300 GeV dark matter particle in channels with large missing energy. This prediction is not yet severely bounded by LHC Run I searches and will be accessible at the LHC Run II in the jet plus missing energy channel with more luminosity. Our analysis also considers astrophysical constraints, pointing out that future direct detection experiments will be sensitive to this scenario.
description: 23 pages, 8 figures. Added 2 figures and more discussions
Anharmonic effects in atomic hydrogen: superconductivity and lattice dynamical stability
Creators: name: Borinaga, Miguel
name: Errea, Ion
name: Calandra, Matteo
name: Mauri, Francesco
name: Bergara, Aitor
Publisher: name: arXiv
Year: 2016
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We present first-principles calculations of metallic atomic hydrogen in the 400-600 GPa pressure range in a tetragonal structure with space group $I4_1/amd$, which is predicted to be its first atomic phase. Our calculations show a band structure close to the free-electron-like limit due to the high electronic kinetic energy induced by pressure. Bands are properly described even in the independent electron approximation fully neglecting the electron-electron interaction. Linear-response harmonic calculations show a dynamically stable phonon spectrum with marked Kohn anomalies. Even if the electron-electron interaction has a minor role in the electronic bands, the inclusion of electronic ex- change and correlation in the density response is essential to obtain a dynamically stable structure. Anharmonic effects, which are calculated within the stochastic self-consistent harmonic approxima- tion, harden high-energy optical modes and soften transverse acoustic modes up to a 20% in energy. Despite a large impact of anharmonicity has been predicted in several high-pressure hydrides, here the superconducting critical temperature is barely affected by anharmonicity, as it is lowered from its harmonic 318 K value only to 300 K at 500 GPa. We atribute the small impact of anharmoncity on superconductivity to the absence of softened optical modes and the fairly uniform distribution of the electron-phonon coupling among the vibrational modes.
Professional identity of nursing students in the post-epidemic era in China: a systematic review and meta-analysis protocol.
Creators: name: Yuan, Ting
name: Zhou, Fen
Publisher: name: Open Science Framework
Year: 2023
Subjects: subject: Medicine and Health Sciences
subject: Education
subject: Higher Education
subject: Nursing
subject: FOS: Health sciences
subject: nursing student
subject: post-epidemic era
subject: professional identity
subject: systematic review

description: A protocol of systematic review and meta-analysis on professional identity of nursing students in the post-epidemic era in China.
Figure S1 from Top-down response to spatial variation in productivity and bottom-up response to temporal variation in productivity in a long-term study of desert ants
Creators: name: Gibb, Heloise
name: Wardle, Glenda M.
name: Greenville, Aaron C.
name: Grossman, Blair F.
name: Dickman, Chris R.
Publisher: name: The Royal Society
Year: 2022
Subjects: subject: Ecology
subject: FOS: Biological sciences

description: Monthly precipitation and mean activity in crests and swales between 1992 and 2013 for each trophic group: a) generalists; b) generalist predators; c) seed harvesters; d) sugar feeders.
Thermal expansion in nanoresonators
Creators: name: Viotti, Agustín Mancardo
name: Monastra, Alejandro G.
name: Moreno, Mariano F.
name: Carusela, M. Florencia
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Inspired by some recent experiments and numerical works related to nanoresonators, we perform classical molecular dynamics simulations to investigate the thermal expansion and the ability of the device to act as a strain sensor assisted by thermally-induced vibrations. The proposed model consists in a chain of atoms interacting anharmonically with both ends clamped to thermal reservoirs. We analyze the thermal expansion and resonant frequency shifts as a function of temperature and the applied strain. For the transversal modes the shift is approximately linear with strain. We also present analytical results from canonical calculations in the harmonic approximation showing that thermal expansion is uniform along the device. This prediction also works when the system operates in a nonlinear oscillation regime at moderate and high temperatures.
description: 12 pages, 6 figures
On the extraction of paramagnon excitations from resonant inelastic X-ray scattering experiments
Creators: name: Lamsal, Jagat
name: Montfrooij, Wouter
Publisher: name: arXiv
Year: 2016
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Resonant X-ray scattering experiments on high-temperature superconductors and related cuprates have revealed the presence of intense paramagnon scattering at high excitation energies, of the order of several hundred meV. The excitation energies appear to show very similar behavior across all compounds, ranging from magnetically ordered, via superconductors, to heavy fermion systems. However, we argue that this apparent behavior has been inferred from the data through model fitting which implicitly imposes such similarities. Using model fitting that is free from such restrictions, we show that the paramagnons are not nearly as well-defined as has been asserted previously, and that some paramagnons might not represent propagating excitations at all. Our work indicates that the data published previously in the literature will need to be re-analyzed with proper models.
description: Submitted to Phys. Rev. B
The Role of Noise in the Spatial Public Goods Game
Creators: name: Javarone, Marco Alberto
name: Battiston, Federico
Publisher: name: arXiv
Year: 2016
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: In this work we aim to analyze the role of noise in the spatial Public Goods Game, one of the most famous games in Evolutionary Game Theory. The dynamics of this game is affected by a number of parameters and processes, namely the topology of interactions among the agents, the synergy factor, and the strategy revision phase. The latter is a process that allows agents to change their strategy. Notably, rational agents tend to imitate richer neighbors, in order to increase the probability to maximize their payoff. By implementing a stochastic revision process, it is possible to control the level of noise in the system, so that even irrational updates may occur. In particular, in this work we study the effect of noise on the macroscopic behavior of a finite structured population playing the Public Goods Game. We consider both the case of a homogeneous population, where the noise in the system is controlled by tuning a parameter representing the level of stochasticity in the strategy revision phase, and a heterogeneous population composed of a variable proportion of rational and irrational agents. In both cases numerical investigations show that the Public Goods Game has a very rich behavior which strongly depends on the amount of noise in the system and on the value of the synergy factor. To conclude, our study sheds a new light on the relations between the microscopic dynamics of the Public Goods Game and its macroscopic behavior, strengthening the link between the field of Evolutionary Game Theory and statistical physics.
description: 14 pages, 3 figures
The Challenges of Persons with Disabilities in Participating in Educational, Economic and Social Activities in South Wollo and Dessie City, North East Ethiopia
Creators: name: Mekonen, Goche Tegegne
name: Bitew Atinaf
name: Tegegne Tessema
Publisher: name: Abyssinia Journal of Business and Social Sciences
Year: 2019

description: The study aims to investigate the challenges of persons with disabilities (PWDs) in participating in educational, economic and social activities. To achieve the objective of the study, 335 participants were randomly selected. The data were collected through questionnaire and interview. The quantitative data collected using questionnaire were analyzed using frequency, percentage and t-test whereas qualitative data gathered through interview were analyzed through thematic analysis. The result of the study indicated that the majority of the participants were illiterate and completed their primary level of education; they had low average monthly income; and they had limited participation in social activities. This result is attributed to negative attitudes of the community, inaccessibility of services due to unfriendly physical environment, lack of facilities and assistive devices and lack of capital. Besides, the study found that there were no statistically significant mean differences between male and female participants in their participation in educational, economic and social activities. Moreover, the result of the study indicated that majority of people with disability in the study areas were marginalized and excluded from educational, economic and social activities. As result, stakeholders should work cooperatively to change the negative attitude of the society towards persons with disabilities to enhance their participation in different aspects of life and activities.
description: Abyssinia Journal of Business and Social Sciences, 2019: Vol. 4 No. 2
Conceptualization of Human Security and Its Policy Implications
Creators: name: Kassaw, Alene
Publisher: name: Abyssinia Journal of Business and Social Sciences
Year: 2019

description: The Horn of Africa is one of the most conflict ridden regions in the Continent. In fact, it is labeled as an extension of the Middle East hotspot given the region’s propensity to the taking shape and escalation of violence marked by rebel activities, military coups, ethnic and racial insurgencies, human rights violations, and state collapse. What is more, in view of the broadening and deepening of the concept of security as well as the emergence of new threats of security in the region spanning from different trans-national crimes such as terrorism, human and drug trafficking, money laundering, illegal migration, cybercrimes, maritime piracy, small arms proliferation etc. to widespread environmental degradation, diseases, climate change and even political policies that are prejudicial to national sovereignty necessitates the re-conceptualization of security in the Horn of Africa. Thus, in this undertaking, secondary sources were used to shed light on the changing conceptualization of security with the aim of elucidating its implications for security policy in the Horn of Africa in general and in Ethiopia in particular.
description: Abyssinia Journal of Business and Social Sciences, 2019: Vol. 4 No. 2
When more of the same is better
Creators: name: Fontanari, José F.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Multiagent Systems (cs.MA)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Problem solving (e.g., drug design, traffic engineering, software development) by task forces represents a substantial portion of the economy of developed countries. Here we use an agent-based model of cooperative problem solving systems to study the influence of diversity on the performance of a task force. We assume that agents cooperate by exchanging information on their partial success and use that information to imitate the more successful agent in the system -- the model. The agents differ only in their propensities to copy the model. We find that, for easy tasks, the optimal organization is a homogeneous system composed of agents with the highest possible copy propensities. For difficult tasks, we find that diversity can prevent the system from being trapped in sub-optimal solutions. However, when the system size is adjusted to maximize performance the homogeneous systems outperform the heterogeneous systems, i.e., for optimal performance, sameness should be preferred to diversity.
Investigating Factors Contributing For Recidivism in Dessie and Woldiya Correctional Centers
Creators: name: Messele, Hayelom Abadi
name: Mekonen, Goche Tegegne
Publisher: name: Abyssinia Journal of Business and Social Sciences
Year: 2019

description: The objective of this study was to investigate the factors contributing for recidivism in Dessie and Woldia correction centers. To achieve the purpose of this research, a mixed research design was employed. The respondents were selected through availability and purposive sampling technique. The data were collected through questionnaire, in-depth interview and key informant interview. Both quantitative and qualitative methods of data analysis were used. The researchers used descriptive statistical tools to analyze the quantitative data. Descriptive tools such as frequency, percentages, and tables are employed to present the results. On the other hand, the qualitative data was analyzed by using thematic analysis methods. As the findings indicated that the factors contributing for recidivism were poverty, unemployment, poor living conditions, family conflict, lack of love and affection; lack of close supervision, separation, divorce, and death of parents. Psychological problems including anxiety, depression, drug abuse, aggressive personality traits too pressurized to aggravate their tendency towards committing crime. Finally, the prison officials and other stakeholders should work to address the economic, social and psychological problems of offenders before and after release.
description: Abyssinia Journal of Business and Social Sciences, 2019: Vol. 4 No. 2
The Role of Religion for Mental Health and Psychological Wellbeing: Implications for Ethiopian Context
Creators: name: Mihretu, Awoke
Publisher: name: Abyssinia Journal of Business and Social Sciences
Year: 2019

description: Spiritual and religious beliefs are common worldwide. At least 90% of the world’s population is currently involved in some form of religious or spiritual practice, but in Ethiopia, its pragmatic value has been poorly investigated. Therefore, this review is aimed to search evidence on the relationship between religion/spirituality, mental health or psychological wellbeing. A review of existing literatures was conducted from two data bases; PubMed and Google Scholar. All review studies focusing on religion/spirituality, psychology or psychological wellbeing and mental health were included. The major themes extracted were: definitions and concepts about religion/spirituality and psychology, threshold of association between religion and different types of mental health disorders. Although there is no study from Ethiopia, this review indicates that religion and spirituality tend to have a positive effect on mental health and psychological wellbeing as well as patients’ overall quality of life. Religion or spirituality has been associated with lower levels of depressive symptoms, fewer symptoms of posttraumatic stress, fewer eating disorder symptoms, less perceived stress, lower risk of suicide, less personality disorder and increased subjective happiness. Psychological well-being, but Ethiopia is naive to train, practice and integrate religion/spirituality in the modern academia and mental health services. Therefore, Ethiopia in particular and the globe in general, integration of religion/spirituality in the training and clinical practice of mental health services is warranted.
description: Abyssinia Journal of Business and Social Sciences, 2019: Vol. 4 No. 2
Bringing Open Science to Life: How RDA Supports Data Sharing
Creators: name: O'Connor, Ryan
name: Asmi, Ari
name: Rettberg, Najla
Publisher: name: Zenodo
Year: 2023

description: This poster presentation outlines the resources produced by the global community efforts of the Research Data Alliance (RDA) to support the open science community. RDA facilitates a substantial number of working groups (WGs) and interest groups (IGs) that work towards structured outputs such as technical specifications recommendations which support the implementation of open science practices at a global level. Many diverse data sharing themes are covered by the work of RDA and also resonate with many of the conference themes. Of particular relevance to the conference themes are the following groups and outputs which will be given visibility by this poster: AI - A new RDA WG is examining the challenges of AI and data visitation. The group addresses ethical, legal, and social challenges of Artificial Intelligence (AI) and Data Visitation (DV) affecting of state-of-the art data technology impacting scientific exchange in the context of data sharing and the European Open Science Cloud (EOSC). Interoperability and Data Management - Data repository interoperability recommendations which provide recommendations with respect to na interoperable packaging and Exchange format for digital content; - PID information Types WG; Puts forward a conceptual model for structuring typed information to identify PIDs FAIR data - First results of the FAIR Data Maturity Model WG. - FAIR hardware: the outcome of an RDA/EOSC Future project to examines the adoption of the FAIR principles in the OS Hardware community. - FAIRsharing registry and recommendations to link standards and data policies Publishing workflows - Dynamic Data citation methodology - ICT tech specification to support the efficient processing of data and linking from publications - Publishing Data Workflows Recommendations WG supporting a universal literature-data cross linking service The poster showcases the outputs and give relevant links to how the audience can also get involved in contributing, developing and maintaining these resources.
description: This poster was presented during the 4th Open Science Fair (25-27 September, Madrid, Spain)
Values at Workplace in the Hotel Industry: The Case of Hotels in Dessie and Kombolecha Towns, Ethiopia
Creators: name: Fentaw, Tesfaye
name: Fikadie, Temsgen
Publisher: name: Abyssinia Journal of Business and Social Sciences
Year: 2019

description: The study assesses the values at workplace factors of employees in the hotels in Dessie and Kombolecha towns. Close ended questionnaire was used to collect primary data by using five-point liker scales. Samples of 78 employees were selected based on simple random sampling method from Kombolecha and Dessie town. The finding of the study revealed, withholding ability of information by the managers from the employees (Mean=2.27), the general trust among the employees (Mean=2.40), the freedom of work for leisure and family (Mean=2.64), trust of the management staff on employees about the ability of employees (Mean=2.67), employing different race and religious group (Mean=2.73) and the fair distribution of works (Mean=2.74) in the sampled hotels were low and very low. The trust level of the information’s comes from the management (Mean=2.97), employee’s freedom to express their feeling and views (Mean=2.96), employee’s apparitions by the management (Mean=2.88) and the fair treatment of women and men (Mean=2.82) were somewhat good but these attributes are also need to be developed.
description: Abyssinia Journal of Business and Social Sciences, 2019: Vol. 4 No. 2
By the community, for the community: A multilingual Open Access Journals Toolkit
Creators: name: Johnson, Rob
name: Chiarelli, Andrea
name: Loffreda, Lucia
name: Mitchell, Dominic
name: Redhead, Clare
Publisher: name: Zenodo
Year: 2023

description: This poster presents the Open Access Journals Toolkit, which will be launched in the second half of 2023. The Toolkit is being developed by the Open Access Scholarly Publishing Association (OASPA) and the Directory of Open Access Journals (DOAJ), with support from an international Editorial Board. The Toolkit will be a unique online resource that will support the development and management of Open Access journals. It will provide vital information to support emerging, developing and established journals, and will provide support for journals to develop a range of established and emerging open access publishing models. The Toolkit addresses a need in the scholarly publishing community, for a diverse, equitable and inclusive resource on OA journal management. The Toolkit will support multilingualism in academic publishing, and will be publicly available in multiple languages. In this sense, the Toolkit will provide users, including publishers, editors, authors, technical providers, reviewers, researchers, and librarians, with the tools needed to support a range of regional initiatives and publishing efforts. To achieve the above, the Toolkit will operate as a community-led initiative driven by a diverse Editorial Board of 12 international experts with support from Research Consulting. The resource is seeking to translate lessons learned by worldwide experts into insights applicable at the local level. This poster introduces the Toolkit and highlight the importance of accessible resources that can help join the dots between local, national and international efforts to enhance knowledge dissemination across borders.
description: This poster was presented during the 4th Open Science Fair (25-27 September, Madrid, Spain)
Precision optical displacement measurements using biphotons
Creators: name: Lyons, Kevin
name: Pang, Shengshi
name: Kwiat, Paul G.
name: Jordan, Andrew N.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We propose and examine the use of biphoton pairs, such as those created in parametric down conversion or four-wave mixing, to enhance the precision and the resolution of measuring optical displacements by position-sensitive detection. We show that the precision of measuring a small optical beam displacement with this method can be significantly enhanced by the correlation between the two photons, given the same optical mode. The improvement is largest if the correlations between the photons are strong, and falls off as the biphoton correlation weakens. More surprisingly, we find that the smallest resolvable parameter of a simple split detector scales as the inverse of the number of biphotons for small biphoton number ("Heisenberg scaling"), because the Fisher information diverges as the parameter to be estimated decreases in value. One usually sees this scaling only for systems with many entangled degrees of freedom. We discuss the transition for the split-detection scheme to the standard quantum limit scaling for imperfect correlations as the biphoton number is increased. An analysis of an $N$-pixel detector is also given to investigate the benefit of using a higher resolution detector. The physical limit of these metrology schemes is determined by the uncertainty in the birth zone of the biphoton in the nonlinear crystal.
description: 12 pages, 5 figures
A generalized sampling and preconditioning scheme for sparse approximation of polynomial chaos expansions
Creators: name: Jakeman, John D.
name: Narayan, Akil
name: Zhou, Tao
Publisher: name: arXiv
Year: 2016
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 42C05, 41A10, 41A63

description: In this paper we propose an algorithm for recovering sparse orthogonal polynomials using stochastic collocation. Our approach is motivated by the desire to use generalized polynomial chaos expansions (PCE) to quantify uncertainty in models subject to uncertain input parameters. The standard sampling approach for recovering sparse polynomials is to use Monte Carlo (MC) sampling of the density of orthogonality. However MC methods result in poor function recovery when the polynomial degree is high. Here we propose a general algorithm that can be applied to any admissible weight function on a bounded domain and a wide class of exponential weight functions defined on unbounded domains. Our proposed algorithm samples with respect to the weighted equilibrium measure of the parametric domain, and subsequently solves a preconditioned $\ell^1$-minimization problem, where the weights of the diagonal preconditioning matrix are given by evaluations of the Christoffel function. We present theoretical analysis to motivate the algorithm, and numerical results that show our method is superior to standard Monte Carlo methods in many situations of interest. Numerical examples are also provided that demonstrate that our proposed Christoffel Sparse Approximation algorithm leads to comparable or improved accuracy even when compared with Legendre and Hermite specific algorithms.
description: 32 pages, 10 figures
The linear response function of an idealized atmosphere. Part 2: Implications for the practical use of the Fluctuation-Dissipation Theorem and the role of operator's non-normality
Creators: name: Hassanzadeh, Pedram
name: Kuang, Zhiming
Publisher: name: arXiv
Year: 2016
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Chaotic Dynamics (nlin.CD)
subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: A linear response function (LRF) relates the mean-response of a nonlinear system to weak external forcings and vice versa. Even for simple models of the general circulation, such as the dry dynamical core, the LRF cannot be calculated from first principles due to the lack of a complete theory for eddy-mean flow feedbacks. According to the Fluctuation-Dissipation Theorem (FDT), the LRF can be calculated using only the covariance and lag-covariance matrices of the unforced system. However, efforts in calculating the LRFs for GCMs using FDT have produced mixed results, and the reason(s) behind the poor performance of the FDT remains unclear. In Part 1 of this study, the LRF of an idealized GCM, the dry dynamical core with Held-Suarez physics, is accurately calculated using Green's functions. In this paper (Part 2), the LRF of the same model is computed using FDT, which is found to perform poorly for some of the test cases. The accurate LRF of Part 1 is used with a linear stochastic equation to show that dimension-reduction by projecting the data onto leading EOFs, which is commonly used for FDT, can alone be a significant source of error. Simplified equations and examples of 2 x 2 matrices are then used to demonstrate that this error arises because of the non-normality of the operator. These results suggest that errors caused by dimension-reduction are a major, if not the main, contributor to the poor performance of the LRF calculated using FDT, and that further investigations of dimension-reduction strategies with a focus on non-normality are needed.
description: revision submitted to the Journal of Atmospheric Sciences; Part 1 is at http://www.people.fas.harvard.edu/~hassanzadeh/HassanzadehKuang2016JAS_Part1.pdf
Dust production in debris discs: constraints on the smallest grains
Creators: name: Thebault, Philippe
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The surface energy constraint puts a limit on the smallest fragment $s_{surf}$ that can be produced after a collision. Based on analytical considerations, this mechanism has been recently identified as been potentially able to prevent the production of small dust grains in debris discs and cut off their size distribution at sizes larger than the blow-out size. We numerically investigate the importance of this effect to find under which conditions it can leave a signature in the small-size end of a disc's particle size distribution (PSD). An important part of this work is to map out, in a disc at steady-state, what is the most likely collisional origin for micron-sized grains, in terms of the sizes of their collisional progenitors. We implement, for the first time, the surface energy constraint into a collisional evolution code. We consider a debris disc extending from 50 to 100AU and 2 different stellar types. We also consider two levels of stirring in the disc: dynamically "hot" (e=0.075) and "cold" (e=0.01). For all cases, we derive $s_{surf}$ maps as a function of target and projectile sizes, $s_t$ and $s_p$, and compare them to equivalent maps for the dust-production rate. We then compute disc-integrated PSDs and estimate the imprint of the surface energy constraint. We find that the ($s_p$,$s_t$) regions of high $s_{surf}$ values do not coincide with those of high dust production rate. As a consequence, the surface energy constraint has generally a weak effect on the system's PSD. The maximum $s_{surf}$-induced depletion of $μ$m-sized grains is $\sim 30$% and is obtained for a sun-like star and a dynamically hot case. For the e=0.01 cases, the surface energy effect is negligible compared to the massive small grain depletion induced by another mechanism: the natural imbalance between dust production and destruction rates in low-stirring discs identified by Thebault&Wu(2008).
description: Accepted for Publication in A&A (abstract truncated for astroph) (v3 and v4 corrected from minor language errors and typos)
Membrane tension is a key determinant of bud morphology in clathrin-mediated endocytosis
Creators: name: Hassinger, Julian E.
name: Oster, George
name: Drubin, David G.
name: Rangamani, Padmini
Publisher: name: arXiv
Year: 2016
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Cell Behavior (q-bio.CB)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: In clathrin-mediated endocytosis (CME), clathrin and various adaptor proteins coat a patch of the plasma membrane, which is reshaped to form a budded vesicle. Experimental studies have demonstrated that elevated membrane tension can inhibit bud formation by a clathrin coat. In this study, we investigate the impact of membrane tension on the mechanics of membrane budding by simulating clathrin coats that either grow in area or progressively induce greater curvature. At low membrane tension, progressively increasing the area of a curvature-generating coat causes the membrane to smoothly evolve from a flat to budded morphology, whereas the membrane remains essentially flat at high membrane tensions. Interestingly, at physiologically relevant, intermediate membrane tensions, the shape evolution of the membrane undergoes a snapthrough instability in which increasing coat area causes the membrane to "snap" from an open, U-shaped bud to a closed, $Ω$-shaped bud. This instability is accompanied by a large energy barrier, which could cause a developing endocytic pit to stall if the binding energy of additional coat is insufficient to overcome this barrier. Similar results were found for a coat of constant area in which the spontaneous curvature progressively increases. Additionally, a pulling force on the bud, simulating a force from actin polymerization, is sufficient to drive a transition from an open to closed bud, overcoming the energy barrier opposing this transition.
Helicity, Topology and Kelvin Waves in reconnecting quantum knots
Creators: name: di Leoni, P. Clark
name: Mininni, P. D.
name: Brachet, M. E.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Helicity is a topological invariant that measures the linkage and knottedness of lines, tubes and ribbons. As such, it has found myriads of applications in astrophysics and solar physics, in fluid dynamics, in atmospheric sciences, and in biology. In quantum flows, where topology-changing reconnection events are a staple, helicity appears as a key quantity to study. However, the usual definition of helicity is not well posed in quantum vortices, and its computation based on counting links and crossings of vortex lines can be downright impossible to apply in complex and turbulent scenarios. We present a new definition of helicity which overcomes these problems. With it, we show that only certain reconnection events conserve helicity. In other cases helicity can change abruptly during reconnection. Furthermore, we show that these events can also excite Kelvin waves, which slowly deplete helicity as they interact nonlinearly, thus linking the theory of vortex knots with observations of quantum turbulence.
Base4NFDI - Creating NFDI-wide basic services in a world of specific domains
Creators: name: Schimmler, Sonja
name: Altenhöner, Reinhard
name: Bernard, Lars
name: Fluck, Juliane
name: Klinger, Axel
name: Lorenz, Sören
name: Mathiak, Brigitte
name: Miller, Bernhard
name: Ritz, Raphael
name: Schörner-Sadenius, Thomas
name: Sczyrba, Alexander
name: Stein, Regine
Publisher: name: Zenodo
Year: 2023
Subjects: NFDI
Base4NFDI
Basisdienste
CoRDI 2023
Basic Services

description: Today, research data is often stored in many different places, difficult to find and only available for a limited time. Base4NFDI creates the basis for better findability, accessibility, interoperability ans reusability of research data. For this purpose, common, technical services are developed together with experts for the data in the different research disciplines. Since many scientific fields have similar requirements for research data, Base4NFDI supports common solutions to avoid parallel developments. Already existing services are thereby adapted or extended to be usable for researchers from other disciplines.
 This slides were presented from Sonja Schimmler at the first Conference on Research Data Infrastructure (CoRDI 2023) on September 14, 2023 in Karlsruhe, Germany. The presentation will give an insight into the idea and structure of Base4NFDI, the processes for developing basic services and the services currently funded.
description: Funded by DFG as part of NFDI. Grant Numbers: 521453681, 521460392, 521462155, 521463400, 521466146, 521471126, 521473512, 521474032, 521475185, 521476232
Mass effect on the lithium abundance evolution of open clusters: Hyades, NGC 752, and M67
Creators: name: Castro, Matthieu
name: Duarte, Tharcísyo
name: Pace, Giancarlo
name: Nascimento, José Dias do
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Lithium abundances in open clusters provide an effective way of probing mixing processes in the interior of solar-type stars and convection is not the only mixing mechanism at work. To understand which mixing mechanisms are occurring in low-mass stars, we test non-standard models, which were calibrated using the Sun, with observations of three open clusters of different ages, the Hyades, NGC 752, and M67. We collected all available data, and for the open cluster NGC 752, we redetermine the equivalent widths and the lithium abundances. Two sets of evolutionary models were computed, one grid of only standard models with microscopic diffusion and one grid with rotation-induced mixing, at metallicity [Fe/H] = 0.13, 0.0, and 0.01 dex, respectively, using the Toulouse-Geneva evolution code. We compare observations with models in a color-magnitude diagram for each cluster to infer a cluster age and a stellar mass for each cluster member. Then, for each cluster we analyze the lithium abundance of each star as a function of mass. The data for the open clusters Hyades, NGC 752, and M67, are compatible with lithium abundance being a function of both age and mass for stars in these clusters. Our models with meridional circulation qualitatively reproduce the general trend of lithium abundance evolution as a function of stellar mass in all three clusters. This study points out the importance of mass dependence in the evolution of lithium abundance as a function of age. Comparison between models with and without rotation-induced mixing shows that the inclusion of meridional circulation is essential to account for lithium depletion in low-mass stars. However, our results suggest that other mechanisms should be included to explain the Li-dip and the lithium dispersion in low-mass stars.
description: 13 pages, 9 figures, 2 tables
Computerized Processing and Analysis of CT Images for Developing a New Criterion in COPD Diagnosis
Creators: name: Hosseini, Mohammad-Parsa
name: Soltanian-Zadeh, Hamid
name: Akhlaghpoor, Shahram
Publisher: name: arXiv
Year: 2016
Subjects: subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: Background: Chronic obstructive pulmonary disease (COPD) is one of the most prevalent and dangerous pulmonary diseases in the world. It is forecasted that COPD will be the third deadly disease in the future. Therefore, developing non-invasive methods for diagnosis of the disease would be helpful for physicians and patients. Methods: Based on clinical investigations and spirometry tests, ten adult patients with COPD (6 male and 4 female) with mean age of 49.8 years were enrolled as the case group. In addition, ten age and sex-matched healthy, non-COPD individuals (6 male and 4 female) with mean age of 45.4 years were recruited as the controls. Lung CT-scan images of the subjects were processed and analyzed by a computer to find a relationship. Findings: The elasticity of lung parenchyma variation was obtained with digital image processing. The normalized average of this pattern was found to be 21.6% in patients and 40.7% in controls. In addition, normalized mean value of Hounsfield unit variations in square 10 pixel * 10 pixel windows in the expiratory images were calculated as a parameter of air-trapping in COPD. Differences between the groups were shown by student t-test (P < 0.05). Conclusion: This study showed that the variation of lung parenchyma elasticity and Hounsfield units are found by processing and analysis of the full inspiration and expiration images. These factors can be used as criteria in diagnosis of COPD. Moreover, the severity of the disease can be presented by the proposed method. Keywords: Air-trapping, Chronic obstructive pulmonary disease, Image processing and analysis, CT-scan lung images
description: http://jims.mui.ac.ir/index.php/jims/article/view/1276
Identification of the defect distribution at ferroelectric domain walls from the evolution of nonlinear dielectric response during aging process
Creators: name: Mokry, Pavel
name: Sluka, Tomas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Motion of ferroelectric domain walls greatly contributes to the macroscopic dielectric and piezoelectric response of ferroelectric materials. The domain wall motion through the ferroelectric material is however hindered by pinning on crystal defects which substantially reduces these contributions. Here, using thermodynamic models based on the Landau-Ginzburg-Devonshire theory, we find a relation between microscopic reversible motion of non-ferroelastic 180-degree domain walls interacting with a periodic array of pinning centers and the nonlinear macroscopic permittivity. We show, that the reversible motion of domain walls can be split into two basic modes. First, the bending of a domain wall between pinning centers, and, second, the uniform movement of domain wall plane. We show that their respective contributions may change when the distribution of pinning centers is rearranged during the material aging. We demonstrate that it is possible to indicate which mechanism of the domain wall motion is affected during material aging. This allows to judge whether the defects only homogeneously accumulate at domain walls or prefer to align in certain directions inside the domain wall plane. We suggest that this information can be obtained using simple macroscopic dielectric measurements and a proper analysis of the nonlinear response. Our results may therefore serve as a simple and useful tool to obtain details on domain wall pinning in an aging process.
description: Accepted in Phys Rev B
Secular models and Kozai resonance for planets in coorbital non-coplanar motion
Creators: name: Giuppone, Cristian A.
name: Leiva, Alejandro M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: In this work, we construct and test an analytical and a semianalytical secular models for two planets locked in a coorbital non-coplanar motion, comparing some results with the case of restricted three body problem. The analytical average model replicates the numerical N-body integrations, even for moderate eccentricities ($\lesssim$ 0.3) and inclinations ($\lesssim10^\circ$), except for the regions corresponding to quasi-satellite and Lidov-Kozai configurations. Furthermore, this model is also useful in the restricted three body problem, assuming very low mass ratio between the planets. We also describe a four-degree-of-freedom semianalytical model valid for any type of coorbital configuration in a wide range of eccentricities and inclinations. {Using a N-body integrator, we have found that the phase space of the General Three Body Problem is different to the restricted case for inclined systems, and establish the location of the Lidov-Kozai equilibrium configurations depending on mass ratio. We study the stability of periodic orbits in the inclined systems, and find that apart from the robust configurations $L_4$, $AL_4$, and $QS$ is possible to harbour two Earth-like planets in orbits previously identified as unstable $U$ and also in Euler $L_3$ configurations, with bounded chaos.
description: 15 pages. 20 figures
Turbulent transport in a strongly stratified forced shear layer with thermal diffusion
Creators: name: Garaud, Pascale
name: Kulenthirarajah, Logithan
Publisher: name: arXiv
Year: 2015
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: This work presents numerical results on the transport of heat and chemical species by shear-induced turbulence in strongly stratified but thermally diffusive environments. The shear instabilities driven in this regime are sometimes called "secular" shear instabilities, and can take place even when the gradient Richardson number of the flow (the square of the ratio of the buoyancy frequency to the shearing rate) is large, provided the Péclet number (the ratio of the thermal diffusion timescale to the turnover timescale of the turbulent eddies) is small. We have identified a set of simple criteria to determine whether these instabilities can take place or not. Generally speaking, we find that they may be relevant whenever the thermal diffusivity of the fluid is very large (typically larger than $10^{14}$cm$^2$/s), which is the case in the outer layers of high-mass stars ($M\ge 10 M_\odot$) for instance. Using a simple model setup in which the shear is forced by a spatially sinusoidal, constant-amplitude body-force, we have identified several regimes ranging from effectively unstratified to very strongly stratified, each with its own set of dynamical properties. Unless the system is in one of the two extreme regimes (effectively unstratified or completely stable), however, we find that (1) only about 10% of the input power is used towards heat transport, while the remaining 90% is viscously dissipated; (2) that the effective compositional mixing coefficient is well-approximated by the model of Zahn (1992), with $D \simeq 0.02 κ_T /J$ where $κ_T$ is the thermal diffusivity and $J$ is the gradient Richardson number. These results need to be confirmed, however, with simulations in different model setups and at higher effective Reynolds number.
description: Submitted to ApJ