cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
title: On the Use of Fractal Void Analysis to Understand Brittle Mode I Compressive Fracture
Creators: name: Ahmed, Ahmed Hassanein Mohamed
Publisher: name: Schulich School of Engineering
Year: 2025
Subjects: subject: fracture
subject: compression
subject: concrete
subject: masonry
subject: stress intensity factor
subject: voids
subject: fractal
subject: Engineering--Civil
subject: Applied Mechanics

description: A key factor limiting the use of fracture mechanics in describing the compressive behaviour of brittle engineering materials is the analytical complexity associated with the need to consider two-dimensional flaw geometries. Researchers have observed that linear elastic (LE) stress fields surrounding voids in compression appear to have predictive value regarding compressive fracture. A theoretical framework for the interpretation of LE stress fields towards compressive fracture, however, remains outstanding. Herein fractal void analysis is proposed to enable interpretation of LE stress fields in the context of Mode I compressive fracture, yielding significant theoretical guidance for this intractable problem. Fractal void analysis consists of considering void surfaces as fractal, and applying what is termed the “small flaw assumption” to analyze stress and energy release rates at the tips of self-affine “surface irregularities”. Fractal void analysis is first applied to two-dimensional LE systems. It is verified against finite element and linear elasticity solutions, and found to account for shape and size effects (key prior limitations). Significantly, two-dimensional fractal void analysis yields efficient KI estimates; peak KI values for radial line cracks emanating from circular voids are calculated to 74% of benchmark numerical values via spreadsheet. Fractal void analysis is then applied to three-dimensional LE systems, where it predicts images of “needle cracks” recently contributed to the literature and suggests two possible mechanisms for planar crack formation. Conclusions from fractal void analysis then support a theoretical analysis of compressive fracture in cementitious materials. The importance of macropore and aggregate distributions in crack initiation is shown. The behaviour of cylinder and masonry prism compression specimens is also considered: successful prediction of cone-shaped fracture patterns in cylinder specimens with length to diameter ratios L/d ≤ 2 is presented, and a discussion of the “lateral tensile splitting theory” in understanding masonry prism fracture is provided. Several areas of potential future research are identified. Theoretical areas include analyses including accounting for mixed-mode fracture and further study of planar crack formation from spheroidal void surfaces. Outstanding experimental work includes correlating test results from materials with simple void distributions to fractal void analysis results.
Reflection Journals - Examples of using this powerful tool to help students synthesize course content
Creators: name: Marquart, Matthea S.
name: Counselman Carpenter, Elisabeth A.
Publisher: name: Columbia University
Year: 2018
Subjects: Web-based instruction
Diaries
Critical thinking
Education
Teaching--Methodology

description: For new and experienced online instructors, or those who work with them, this interactive session will share examples of well received reflection journal assignments from online courses at Columbia University.  The presenters will open by touching on research on the value of reflection journals, sample uses of reflection journal assignments, and how to provide instructor feedback and grading to deepen student work on future journal entries while maintaining a feasible instructor workload.  Next, the presenters will share examples of reflection journal assignment instructions, grading rubrics, and lessons learned from two online courses.  Finally, the presenters will facilitate a chat-based discussion to encourage the session participants to share their experiences, advice, and questions.

Most learning management systems, including Blackboard and Canvas, include a journal tool.  This session will help instructors share and spark ideas of ways to use this tool effectively in their own online courses, regardless of the course topic or academic discipline.

The presenters will be Beth Counselman Carpenter, Assistant Professor, Southern Connecticut State University's School of Health and Human Services; and Matthea Marquart, Director of Administration, Online Campus, and Lecturer, Columbia University School of Social Work.
title: Enhancing Multi-Signature Cryptocurrency Wallets with Risk-Based Authentication
Creators: name: Buhler, Matthew
Publisher: name: Graduate Studies
Year: 2025
Subjects: subject: Cryptographic Key Management
subject: Blockchain
subject: Cryptocurrencies
subject: Risk Management
subject: Risk Based Authentication
subject: Credentials
subject: Multi-Signature Wallets
subject: Computer Science

description: Cryptographic keys are among the most critical security tools in the world. At a basic level, these keys are passwords, and their effectiveness depends on remaining confidential and accessible to authorized users. Historically, key management was confined to a small group of technical experts because of the complexity of securing these secrets (i.e., private keys). However, due to blockchain and cryptocurrencies, millions of users are now directly managing their cryptographic keys. This shift has driven innovations to support individual key management and has created an opportunity to explore these innovations and propose further enhancements. This work examines these innovations, such as multi-signature keys and hierarchical deterministic seed phrases. We investigate the challenges between organizational and individual key and risk management practices and identify issues with multi-signature wallets. To address these challenges, we propose a novel risk-based authentication system that uses a hierarchical credential system to align risk with the confidence of a user’s identity and intent. From here, we design this system and evaluate its security and usability against a conventional multi-sig wallet using a hardware wallet paired with a mobile phone.We conclude by discussing how the underlying key management problem is closely related to identity and how there is a need to bind ownership and access of private keys to a more extensive set of credentials spanning social, physical, temporal, and geographic dimensions. We then recommend an approach that builds upon this work.
title: Metabolomics comparison between Delta and Omicron-infected individuals
Creators: name: Pimentel Guerrero, Eric Iván
Publisher: name: Graduate Studies
Year: 2025
Subjects: subject: SARS-CoV-2
subject: COVID-19
subject: Delta
subject: Omicron
subject: Metabolomics
subject: Biochemistry
subject: Biophysics--Medical
subject: Virology

description: At the end of 2019, SARS-CoV-2, the novel coronavirus emerged causing a widespread increase in airway and lung infections that was driven by different viral variants. Only the variants with significant differences in transmissibility, disease severity, reduction in neutralization by antibodies, and reduction in treatment effectiveness were designated as variants of concern (VOC). Among these variants, the Delta and Omicron forms have demonstrated marked differences in transmissibility and disease severity. This study aims to identify the plasma metabolomics differences that characterize Delta-infected compared to Omicron-infected patients, analyze the severity within these SARS-CoV-2 variant infections, and investigate how vaccination status and corticosteroid treatment impacted the plasma metabolomic profiles of these patients infected with these variants. Our hypothesis is that the metabolomic profiles will reveal significant metabolomic differences between the two variants, reflecting their varied clinical outcomes. Furthermore, we hypothesize that the treatments used during each variant’s wave of infection may be reflected in the plasma metabolome of infected individuals. This study demonstrates that not only are there differences in plasma metabolites that distinguish Delta and Omicron-infected individuals, but also that metabolites do differentiate between various degrees of severity.
Telatrygon zugei
Creators: name: Zainal Abidin, Danial Hariz
name: Lavoué, Sébastien
name: Mohd Abu Hassan Alshari, Norli Fauzani
name: Mohd. Nor, Siti Azizah
name: A. Rahim, Masazurah
name: Mohammed Akib, Noor Adelyna
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Elasmobranchii
Myliobatiformes
Dasyatidae
Telatrygon
Telatrygon zugei

description: Telatrygon zugei (Bürger, 1841) Figure 2B Material examined. MALAYSIA • 1 ♀, 148 mm DW, tail missing; Kedah State, Kuala Kedah, Kuala Muda Whispering Market; 05.578°N, 100.341°E; 6 Dec. 2018; Danial H. Zainal Abidin, Norli F.M.A.H. Alshari leg.; USMFC (1) 00002. Identification. A small species of dasyatid (maximal disc width less than 300 mm); elongated snout with largely concave disc anterior margins; eye small; no dark transverse band through the eyes; dorsal surface of the disc uniformly brown, ventral side of the disc uniformly pale greyish (Carpenter and Niem 1999a). According to Weigmann (2011), T. zugei can be distinguished from all other stingrays occurring in this region by its very elongated snout with the broadly concave anterior margins of the disc. A common coastal species in Southeast Asia regularly occurring in brackish environments. Generic classification follows Last et al. (2016); previously classified in the genus Dasyatis.
description: Published as part of Zainal Abidin, Danial Hariz, Lavoué, Sébastien, Mohd Abu Hassan Alshari, Norli Fauzani, Mohd. Nor, Siti Azizah, A. Rahim, Masazurah & Mohammed Akib, Noor Adelyna, 2021, Ichthyofauna of Sungai Merbok Mangrove Forest Reserve, northwest Peninsular Malaysia, and its adjacent marine waters, pp. 601-631 in Check List 17 (2) on page 607, DOI: 10.15560/17.2.601
description: {"references": ["Carpenter KE, Niem VH (Eds.) (1999 a) FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Volume 3. Batoid fishes, chimaeras and bony fishes part 1 (Elopidae to Linophrynidae). FAO, Rome, Italy, pp. 1397 - 2068.", "Weigmann S (2011) Contribution to the taxonomy and distribution of eight ray species (Chondrichthyes, Batoidea) from coastal waters of Thailand. Verhandlungen des Naturwissenschaftlichen Vereins in Hamburg 46: 249 - 312. https: // doi. org / 10.5402 / 2012 / 860768", "Last PR, Naylor G, Manjaji-Matsumoto BM (2016) A revised classification of the family Dasyatidae (Chondrichthyes: Myliobati- formes) based on new morphological and molecular insights. Zootaxa 4139: 345 - 368. https: // doi. org / 10.11646 / zootaxa. 4139.3.2"]}
Revisiting non-Gaussianity in non-attractor inflation models in the light of the cosmological soft theorem
Creators: name: Suyama, Teruaki
name: Tada, Yuichiro
name: Yamaguchi, Masahide
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We revisit the squeezed-limit non-Gaussianity in the single-field non-attractor inflation models from the viewpoint of the cosmological soft theorem. In the single-field attractor models, inflaton's trajectories with different initial conditions effectively converge into a single trajectory in the phase space, and hence there is only one \emph{clock} degree of freedom (DoF) in the scalar part. Its long-wavelength perturbations can be absorbed into the local coordinate renormalization and lead to the so-called \emph{consistency relation} between $n$- and $(n+1)$-point functions. On the other hand, if the inflaton dynamics deviates from the attractor behavior, its long-wavelength perturbations cannot necessarily be absorbed and the consistency relation is expected not to hold any longer. In this work, we derive a formula for the squeezed bispectrum including the explicit correction to the consistency relation, as a proof of its violation in the non-attractor cases. First one must recall that non-attractor inflation needs to be followed by attractor inflation in a realistic case. Then, even if a specific non-attractor phase is effectively governed by a single DoF of phase space (represented by the exact ultra-slow-roll limit) and followed by a single-DoF attractor phase, its transition phase necessarily involves two DoF in dynamics and hence its long-wavelength perturbations cannot be absorbed into the local coordinate renormalization. Thus, it can affect local physics, even taking account of the so-called \emph{local observer effect}, as shown by the fact that the bispectrum in the squeezed limit can go beyond the consistency relation. More concretely, the observed squeezed bispectrum does not vanish in general for long-wavelength perturbations exiting the horizon during a non-attractor phase.
description: 19 pages, 2 figures; v2: Eq. (80) and references added; v3: acknowledgments added; v4: published version
Emergency Preparedness Training for Hospital Nursing Staff, New York City, 2012–2016
Creators: name: Jacobs‐Wingo, Jasmine L.
name: Schlegelmilch, Jeffrey
name: Berliner, Maegan S.
name: Airall‐Simon, Gloria
name: Lang, William
Publisher: name: Columbia University
Year: 2018
Subjects: subject: Emergency management--Planning
subject: Nursing
subject: FOS: Health sciences
subject: Curriculum planning
subject: Nurses--Training of

description: Purpose
Many nurses are trained inadequately in emergency preparedness (EP), preventing them from effectively executing response roles during disasters, such as chemical, biological, radiological, nuclear, and explosive (CBRNE) events. Nurses also indicate lacking confidence in their abilities to perform EP activities. The purpose of this article is to describe the phased development of, and delivery strategies for, a CBRNE curriculum to enhance EP among nursing professionals. The New York City (NYC) Department of Health and Mental Hygiene (DOHMH) and the National Center for Disaster Preparedness at Columbia University's Earth Institute led the initiative.

Methods
Curriculum development included four phases. In Phases I and II, nursing staff at 20 participating NYC hospitals conducted 7,177 surveys and participated in 20 focus groups to identify training gaps in EP. In Phase III, investigators developed and later refined the CBRNE curriculum based on gaps identified. In Phase IV, 22 nurse educators (representing 7 of the original 20 participating hospitals) completed train‐the‐trainer sessions. Of these nurse educators, three were evaluated on their ability to train other nurses using the curriculum, which investigators finalized.

Findings
The CBRNE curriculum included six modules, a just‐in‐time training, and an online annual refresher course that addressed EP gaps identified in surveys and focus groups. Among the 11 nurses who were trained by three nurse educators during a pilot training, participant knowledge of CBRNE events and response roles increased from an average of 54% (range 45%–75%) on the pre‐test to 89% (range 80%–90%) on the posttest.

Conclusions
By participating in nursing CBRNE training, nurses increased their knowledge of and preparedness to respond to disasters. The train‐the‐trainer curriculum is easily adaptable to meet the needs of other healthcare settings.

Clinical Relevance
The CBRNE curriculum can be used to train nurses to better prepare for and more effectively respond to disasters.
Fractional Brownian motion and the critical dynamics of zipping polymers
Creators: name: Walter, Jean-Charles
name: Ferrantini, Alessandro
name: Carlon, Enrico
name: Vanderzande, Carlo
Publisher: name: arXiv
Year: 2011
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We consider two complementary polymer strands of length $L$ attached by a common end monomer. The two strands bind through complementary monomers and at low temperatures form a double stranded conformation (zipping), while at high temperature they dissociate (unzipping). This is a simple model of DNA (or RNA) hairpin formation. Here we investigate the dynamics of the strands at the equilibrium critical temperature $T=T_c$ using Monte Carlo Rouse dynamics. We find that the dynamics is anomalous, with a characteristic time scaling as $τ\sim L^{2.26(2)}$, exceeding the Rouse time $\sim L^{2.18}$. We investigate the probability distribution function, the velocity autocorrelation function, the survival probability and boundary behaviour of the underlying stochastic process. These quantities scale as expected from a fractional Brownian motion with a Hurst exponent $H=0.44(1)$. We discuss similarities and differences with unbiased polymer translocation.
description: 7 pages, 8 figures
title: The influence of two physical activity programs on bone and muscle health in youth with cerebral palsy and other neuromotor impairments.
Creators: name: Hodgson, Erin
Publisher: name: Graduate Studies
Year: 2025
Subjects: subject: Bone Health
subject: Cerebral palsy
subject: pQCT
subject: Neuromotor impairments
subject: Engineering--Biomedical
subject: Human Development

description: Weight-bearing physical activity is crucial for building strong bones, especially during childhood and adolescence when bones grow rapidly. During this time, physical activity, muscle-bone interactions, and gravity help stimulate bone development. However, in conditions that limit mobility, such as cerebral palsy (CP) and other non-progressive neuromotor impairments (CP-like), physical activity is reduced, which can lead to poor bone health. This increases the risk of fractures and may lead to osteoporosis in adults with CP. This thesis examines bone health in children and youth with CP and CP-like conditions using peripheral quantitative computed tomography (pQCT) scans of the tibiae. Bone and muscle parameters, including bone mineral content (BMC), bone mineral density (both trabecular and cortical; BMD), bone size, and muscle size, were compared to age-, sex-, and ethnicity-matched peers from a typically developing population. A total of 22 participants from all Gross Motor Function Classification System (GMFCS) levels (I-V) were included. This study found smaller, thinner and weaker bones and lower muscle strength in children and adolescents with CP and CP-like conditions across all GMFCS levels, with deficits relating to functional ability. As weaker bones increase the incidence of fragility fractures, causing pain and predisposing future comorbidities, this thesis further evaluated the effects of two physical activity programs on bone and muscle strength. Robot-assisted walking in three participants with the greatest functional limitations found upright mobility may improve bone strength. In contrast, power training in eight participants with the greatest functional abilities found no adaptations in bone or muscle. These findings suggest that while bone health is a concern across all functional abilities, adaptations appear to correlate to the loading one previously experienced, having the greatest impacts in those who do not regularly ambulate. This highlights the importance of tailored physical activity programs based on functional ability during growth and could inform strategies for improving musculoskeletal health in children and youth with CP and CP-like conditions.
Quasi-Dilaton: Theory and Cosmology
Creators: name: D'Amico, Guido
name: Gabadadze, Gregory
name: Hui, Lam
name: Pirtskhalava, David
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: General Relativity (GR), with or without matter fields, admits a natural extension to a scale invariant theory that requires a dilaton. Here we show that the recently formulated massive GR, minimally coupled to matter, possesses a new global symmetry related to scaling of the reference coordinates w.r.t. the physical ones. The field enforcing this symmetry, dubbed here quasi-dilaton, coincides with an ordinary dilaton if only pure gravity is considered, but differs from it when the matter Lagrangian is present. We study: (1) Theoretical consistency of massive GR with the quasi-dilaton; (2) Consistency with observations for spherically symmetric sources on (nearly) flat backgrounds; (3) Cosmological implications of this theory. We find that: (I) The theory with the quasi-dilaton is as consistent as massive GR is. (II) The Vainshtein mechanism is generically retained, owing to the fact that in the decoupling limit there is an enhanced symmetry, which turns the quasi-dilaton into a second galileon, consistently coupled to a tensor field. (III) Unlike in massive GR, there exist flat FRW solutions. In particular, we find self-accelerated solutions and discuss their quadratic perturbations. These solutions are testable by virtue of the different effective Newton's constants that govern the Hubble expansion and structure growth.
description: v2: discussion of quadratic perturbations in section 5 modified with more positive outlook. References added
To switch or not to switch: Intentions to switch to injectable PrEP among gay and bisexual men with at least twelve months oral PrEP experience
Creators: name: Meyers, Kathrine
name: Wu, Yumeng
name: Brill, Atrina
name: Sandfort, Theodorus G.
name: Golub, Sarit A.
Publisher: name: Columbia University
Year: 2018
Subjects: HIV (Viruses)--Prevention
Gay men--Sexual behavior
Bisexual men--Sexual behavior
Drugs--Dosage forms
Pre-exposure prophylaxis

description: Background
Phase III trials of long-acting injectable (LAI) PrEP, currently underway, have great potential for expanding the menu of HIV prevention options. Imagining a future in which multiple PrEP modalities are available to potential users of biomedical HIV prevention, we investigated which factors might help direct a patient-physician shared-decision making process to optimize the choice of biomedical HIV prevention method.

Methods
Participants (n = 105; ages 19–63; 46.7% men of color) were former participants in a PrEP demonstration project and had taken daily oral PrEP for ≥ 12 months. Participants were given information about LAI PrEP and asked whether they would be interested in switching from oral to LAI PrEP. Participants were also asked about specific pros/cons of LAI PrEP, PrEP attitudes and experiences, and personality factors.

Results
Two-thirds (66.7%) of current oral PrEP users would switch to LAI PrEP. Intention to switch was associated with product-level and psychosocial factors. Attitudes towards logistical factors (i.e. getting to regular clinic visits for recurring shots) featured more prominently than factors related to the physical experience of PrEP modality (i.e., concerns about injection pain) as motivators for switching. In a multivariate regression model, psychosocial factors including the emotional burden of daily pill taking, deriving a sense of responsibility from PrEP use, and self-identifying as an early adopter, were the strongest predictors of switching.

Conclusions
These data underscore the importance of attending not only to product-level factors, but also to the logistical and psychological experience of prevention methods for users. Findings have significant implications for the development of patient education materials and patient-provider shared decision aids.
Glycogen synthase kinase-3 signaling in Alzheimer's disease : regulation of beta-amyloid precursor protein processing and amyloid beta protein production
Creators: name: Ly, Philip T.T.
Publisher: name: University of British Columbia
Year: 2012

description: Glycogen synthase kinase 3 (GSK3) is a serine/threonine kinase that plays a part in a number of physiological processes ranging from glycogen metabolism to gene transcription. Recent studies indicated that GSK3 also involved in the formation of Alzheimer’s disease (AD) pathologies: neurofibrillary tangles and amyloid plaques. Neurofibrillary tangles develop when abnormal tau proteins accumulate inside neurons and form insoluble filaments, and amyloid plaques develop when the amyloid β protein (Aβ) accumulates in increasingly insoluble forms. The Aβ peptide is generated through sequential cleavages of the β-amyloid precursor protein by β-secretase (BACE1) and γ-secretase. Accumulation of insoluble Aβ is believed to trigger the initial series of neurodegenerative events leading to AD. Therefore, inhibition of the pathways that lead to Aβ generation will have therapeutic implications for AD treatment. The mechanism by which GSK3 affects APP processing and Aβ production has been controversial. Previous published reports have found differential effects on GSK3-mediated APP processing. This thesis entails a thorough investigation of GSK3’s role in APP processing and Aβ production. First, the therapeutic effects of the anti-convulsant drug, valproic acid (VPA) were tested in AD modeled mice. VPA, a known GSK3 inhibitor could interfere with Aβ production, and rescued memory deficits. In addition to inhibiting GSK3 activity, VPA also stimulate a plethora of signaling cascades. To further our understanding of GSK3’s effect on APP processing, a GSK3 specific pharmacological inhibitor (AR-A014418) and siRNA technologies were used in our systems. With specific GSK3β inhibition, we showed that BACE1-mediated cleavage of APP and Aβ production were reduced. Moreover, GSK3β induced BACE1 gene expression depends on NFκB activity. Additionally, specific inhibition of GSK3 also reduced Aβ production and neuritic plaque formation in AD modeled mice, as well as improved memory functions. Finally, this thesis examined in detail the role of GSK3 in AD pathogenesis. This study demonstrated for the first time that the GSK3β signaling pathway regulates BACE1 transcription and facilitates Aβ production. These findings reinforced the notion that specific GSK3 inhibition is a safe and effective approach for treating AD.
Gymnura poecilura
Creators: name: Zainal Abidin, Danial Hariz
name: Lavoué, Sébastien
name: Mohd Abu Hassan Alshari, Norli Fauzani
name: Mohd. Nor, Siti Azizah
name: A. Rahim, Masazurah
name: Mohammed Akib, Noor Adelyna
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Elasmobranchii
Myliobatiformes
Gymnuridae
Gymnura
Gymnura poecilura

description: Gymnura poecilura (Shaw, 1804) Figure 2C Material examined. MALAYSIA • 1 ♂, 475 mm DW; Kedah State, Kuala Kedah, Kuala Muda Whispering Market; 05.578°N, 100.341°E; 6 Dec. 2018; Danial H. Zainal Abidin, Norli F.M.A.H. Alshari leg.; USMFC (104) 00001. • 1 ♂, 285 mm DW; Kedah State, Kuala Kedah, Kuala Muda Whispering Market; 05.578°N, 100.341°E; 6 Dec. 2018; Danial H. Zainal Abidin, Norli F.M.A.H. Alshari leg.; USMFC (104) 00002.
description: Published as part of Zainal Abidin, Danial Hariz, Lavoué, Sébastien, Mohd Abu Hassan Alshari, Norli Fauzani, Mohd. Nor, Siti Azizah, A. Rahim, Masazurah & Mohammed Akib, Noor Adelyna, 2021, Ichthyofauna of Sungai Merbok Mangrove Forest Reserve, northwest Peninsular Malaysia, and its adjacent marine waters, pp. 601-631 in Check List 17 (2) on page 607, DOI: 10.15560/17.2.601
The diversity of symplectic Calabi-Yau six-manifolds
Creators: name: Fine, Joel
name: Panov, Dmitri
Publisher: name: arXiv
Year: 2011
Subjects: subject: Symplectic Geometry (math.SG)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 53D05

description: Given an integer b and a finitely presented group G we produce a compact symplectic six-manifold with c_1 = 0, b_2 > b, b_3 > b and fundamental group G. In the simply-connected case we can also arrange for b_3 = 0; in particular these examples are not diffeomorphic to Kähler manifolds with c_1 = 0. The construction begins with a certain orientable four-dimensional hyperbolic orbifold assembled from right-angled 120-cells. The twistor space of the hyperbolic orbifold is a symplectic Calabi-Yau orbifold; a crepant resolution of this last orbifold produces a smooth symplectic manifold with the required properties.
description: 18 pages, 1 figure. v2 added proof that b_3 can also be taken arbitrarily large
Mirror-Descent Inverse Kinematics for Box-constrained Joint Space
Creators: name: Kobayashi, Taisuke
name: Jin, Takanori
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: To control humanoid robots, the reference pose of end effector(s) is planned in task space, then mapped into the reference joints by IK. By viewing that problem as approximate quadratic programming (QP), recent QP solvers can be applied to solve it precisely, but iterative numerical IK solvers based on Jacobian are still in high demand due to their low computational cost. However, the conventional Jacobian-based IK usually clamps the obtained joints during iteration according to the constraints in practice, causing numerical instability due to non-smoothed objective function. To alleviate the clamping problem, this study explicitly considers the joint constraints, especially the box constraints in this paper, inside the new IK solver. Specifically, instead of clamping, a mirror descent (MD) method with box-constrained real joint space and no-constrained mirror space is integrated with the Jacobian-based IK, so-called MD-IK. In addition, to escape local optima nearly on the boundaries of constraints, a heuristic technique, called $ε$-clamping, is implemented as margin in software level. Finally, to increase convergence speed, the acceleration method for MD is integrated assuming continuity of solutions at each time. As a result, the accelerated MD-IK achieved more stable and enough fast tracking performance compared to the conventional IK solvers. The low computational cost of the proposed method mitigated the time delay until the solution is obtained in real-time humanoid gait control, achieving a more stable gait.
description: 6 pages, 4 figures
Composition of Collaborative Innovation Networks: An Investigation of Process Characteristics and Outcomes
Creators: name: Veflen, Nina
name: Scholderer, Joachim
name: Elvekrok, Ingunn
Publisher: name: International Journal on Food System Dynamics
Year: 2019
Subjects: Collaborative innovation networks; composition; manufacturer; suppliers

description: In this study we test how different ways of composing collaborative action networks influence food innovation. Networks have received considerable attention in the literature and are perceived to enhance the likelihood of innovation success by overcoming resource and capability deficiencies. While previous studies of collaborate innovation in the food sector have been mostly qualitative case studies of one or a few networks, we compare 96 networks which were all structured according to the same network template. After content-analysing archive data, we estimated a vector-generalised linear model with binomial response distributions and probit link functions; with network composition as the predictor and the innovation process charateristics and outcomes as response variables. Our findings show that differently composed manufacturer networks lead to different outcomes and different process characteristics. We find that strong management and coordination of activities are more important for heterogeneous manufacturer networks than for homogeneous manufacturer networks, and that vertically composed networks with suppliers contribute to efficiency gains to a higher extent than networks consisting solely of manufacturers.
description: International Journal on Food System Dynamics, Vol 10, No 1 (2019)
Additional file 2 of Physiological, metabolomic, and transcriptomic reveal metabolic pathway alterations in Gymnocypris przewalskii due to cold exposure
Creators: name: Liu, Sijia
name: Tian, Fei
name: Qi, Delin
name: Qi, Hongfang
name: Wang, Yang
name: Xu, Shixiao
name: Zhao, Kai
Publisher: name: figshare
Year: 2023
Subjects: subject: Genetics
subject: FOS: Biological sciences

description: Additional file 2.
title: Applying Dynamic Capabilities in Business Model Innovation: An Exploratory Case Study in a Self-Managing Organization
Creators: name: Mayer, Matthew
Publisher: name: Graduate Studies
Year: 2025
Subjects: subject: Business model innovation
subject: Self-managing organization
subject: Dynamic capabilities
subject: Business Administration--Management

description: Despite a significant amount of literature on business model innovation (BMI) suggesting the importance of organizational design as a firm-level moderator for successful BMI outcomes, few studies have addressed it directly. Self-managing organizations (SMO) are a type of less-hierarchical organization that aims to redefine hierarchical structures, especially the role of traditional managers. Like any firm, SMOs that innovate well may enjoy Schumpeterian entrepreneurial rents and, if effective at continually reconfiguring their resources, may sustain a competitive advantage in line with the dynamic capabilities (DCs) theoretical perspective. Despite practitioners suggesting that SMOs are better at adapting and responding to environmental conditions, few public-facing examples of BMI in these organizations exist in either popular management literature or scholarship. This intensive, exploratory case study researched an SMO that transformed its resources several times to pursue an array of BMIs over time. Interviews, observation and archival data were collected over 18 months. The study results showed that balancing hierarchical tensions, enacting collaborative routines for knowledge creation and configuring a community of leaders are foundational DCs when BMI is practiced in an SMO. In addition to outlining the routines and practices for DCs for BMI in an SMO, the study also proposed a model for how these DCs are applied. For scholars and practitioners, the study discusses the role of a manager, innovation champion and network for SMOs engaging in BMI. In practice, identifiable organizational routines and processes are present, and practices can be strategically selected to enact multiple DCs simultaneously. The exploratory nature of this case study elucidated future research to advance the field of BMI and SMOs.
Inhomogeneous vacuum energy
Creators: name: Wands, David
name: De-Santiago, Josue
name: Wang, Yuting
Publisher: name: arXiv
Year: 2012
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Vacuum energy remains the simplest model of dark energy which could drive the accelerated expansion of the Universe without necessarily introducing any new degrees of freedom. Inhomogeneous vacuum energy is necessarily interacting in general relativity. Although the four-velocity of vacuum energy is undefined, an interacting vacuum has an energy transfer and the vacuum energy defines a particular foliation of spacetime with spatially homogeneous vacuum energy in cosmological solutions. It is possible to give a consistent description of vacuum dynamics and in particular the relativistic equations of motion for inhomogeneous perturbations given a covariant prescription for the vacuum energy, or equivalently the energy transfer four-vector, and we construct gauge-invariant vacuum perturbations. We show that any dark energy cosmology can be decomposed into an interacting vacuum+matter cosmology whose inhomogeneous perturbations obey simple first-order equations.
description: 8 pages; v2 clarified discussion of Chaplygin gas model, references added
Parameter and density estimation from real-world traffic data: A kinetic compartmental approach
Creators: name: Pereira, Mike
name: Baykas, Pinar Boyraz
name: Kulcsár, Balázs
name: Lang, Annika
Publisher: name: arXiv
Year: 2021
Subjects: subject: Signal Processing (eess.SP)
subject: Numerical Analysis (math.NA)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Mathematics
subject: 65M12, 35L03, 35D40, 62G05

description: The main motivation of this work is to assess the validity of a LWR traffic flow model to model measurements obtained from trajectory data, and propose extensions of this model to improve it. A formulation for a discrete dynamical system is proposed aiming at reproducing the evolution in time of the density of vehicles along a road, as observed in the measurements. This system is formulated as a chemical reaction network where road cells are interpreted as compartments, the transfer of vehicles from one cell to the other is seen as a chemical reaction between adjacent compartment and the density of vehicles is seen as a concentration of reactant. Several degrees of flexibility on the parameters of this system, which basically consist of the reaction rates between the compartments, can be considered: a constant value or a function depending on time and/or space. Density measurements coming from trajectory data are then interpreted as observations of the states of this system at consecutive times. Optimal reaction rates for the system are then obtained by minimizing the discrepancy between the output of the system and the state measurements. This approach was tested both on simulated and real data, proved successful in recreating the complexity of traffic flows despite the assumptions on the flux-density relation.
description: 31 pages, 18 figures, 4 tables
Deformation of LeBrun's ALE metrics with negative mass
Creators: name: Honda, Nobuhiro
Publisher: name: arXiv
Year: 2012
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: In this article we investigate deformations of a scalar-flat Kähler metric on the total space of complex line bundles over CP^1 constructed by C. LeBrun. In particular, we find that the metric is included in a one-dimensional family of such metrics on the four-manifold, where the complex structure in the deformation is not the standard one.
description: 20 pages, no figure. V2: added two references, filled a gap in the proof of Theorem 1.2. V3: corrected a wrong statement about Kuranishi family of a Hirzebruch surface stated in the last paragraph in the proof of Theorem 1.2, and fixed a relevant error in the proof. Also added a reference [24] about Kuranishi family of Hirzebruch surfaces
Meta-analyses of expression profiling data in the postmortem human brain
Creators: name: Mistry, Meeta
Publisher: name: University of British Columbia
Year: 2013

description: Schizophrenia is a severe psychiatric illness for which the precise etiology remains unknown. Studies using postmortem human brain have become increasingly important in schizophrenia research, providing an opportunity to directly investigate the diseased brain tissue. Gene expression profiling technologies have been used by a number of groups to explore the postmortem human brain and seek genes which show changes in expression correlated with schizophrenia. While this has been a valuable means of generating hypotheses, there is a general lack of consensus in the findings across studies. Expression profiling of postmortem human brain tissue is difficult due to the effect of various factors that can confound the data. The first aim of this thesis was to use control postmortem human cortex for identification of expression changes associated with several factors, specifically: age, sex, brain pH and postmortem interval. I conducted a meta-analysis across the control arm of eleven microarray datasets (representing over 400 subjects), and identified a signature of genes associated with each factor. These genes provide critical information towards the identification of problematic genes when investigating postmortem human brain in schizophrenia and other neuropsychiatric illnesses. The second aim of this thesis was to evaluate gene expression patterns in the prefrontal cortex associated with schizophrenia by exploring two methods of analysis: differential expression and coexpression. Seven schizophrenia microarray studies of prefrontal cortex were combined for a total of 153 subjects with schizophrenia and 153 healthy controls. Meta-analysis was conducted with careful consideration for the effects of covariates, revealing a robust list of 98 differentially expressed ‘schizophrenia genes’. Using the same seven schizophrenia datasets, coexpression networks were generated for control and schizophrenia cohorts within each dataset and then combined across studies using a rank aggregation approach. Topological properties of our ‘schizophrenia genes’ were evaluated in the context of each network, highlighting differences in correlation structure of these genes in the control and schizophrenia brain. Together these results converge towards a general conclusion, emphasizing that the integration of postmortem human brain expression profiling data improves statistical power and is particularly useful in detecting subtle yet consistent changes in expression associated with schizophrenia
title: Machine Learning for Robust Detection and Mitigation of GNSS Multipath
Creators: name: Phillips, Christian Michael
Publisher: name: Graduate Studies
Year: 2025
Subjects: subject: GNSS
subject: Machine Learning
subject: Deep Learning
subject: Multipath
subject: Positioning
subject: Navigation
subject: Engineering

description: Distortion to the correlation function caused by multipath and non-line of sight signals can result in pseudorange errors on the order of several tens of meters in urban canyon environments. To address this problem, a deep learning approach for classifying multipath and estimating observation weights from a global navigation satellite systems (GNSS) receiver correlation function is presented. This approach uses a 1-dimensional convolutional neural network, suitable for embedded applications, to classify the magnitude of pseudorange error associated with correlation functions and to generate a multipath probability used for deriving observation weights. The network is trained and tested on live GNSS data collected in a challenging urban environment. The capability of the model to remove high error measurements for a least-squares positioning solution and to generate weights for a weighted least-squares positioning solution is explored. The network has proven to be effective at detecting measurements with high multipath ranging error, and to effectively generalize to unseen data. The removal of detected measurements reduced positioning error by up to 80%, and the use of deep learning derived weights in the positioning solution reduced positioning error by a further 50%. In both cases, positioning errors were comparable to what is expected for an open-sky single frequency standalone positioning solution.
Chiloscyllium indicum
Creators: name: Zainal Abidin, Danial Hariz
name: Lavoué, Sébastien
name: Mohd Abu Hassan Alshari, Norli Fauzani
name: Mohd. Nor, Siti Azizah
name: A. Rahim, Masazurah
name: Mohammed Akib, Noor Adelyna
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Elasmobranchii
Orectolobiformes
Hemiscylliidae
Chiloscyllium
Chiloscyllium indicum

description: Chiloscyllium indicum (Gmelin, 1789) Figure 2D Material examined. MALAYSIA • 1, 170 mm TL; Kedah State, Kampung Batu Lintang, Pompang Batu Lintang; 05.625°N, 100.394°E; 10 Oct. 2019; Sébastien Lavoué leg.; USMFC (114) 00001.
description: Published as part of Zainal Abidin, Danial Hariz, Lavoué, Sébastien, Mohd Abu Hassan Alshari, Norli Fauzani, Mohd. Nor, Siti Azizah, A. Rahim, Masazurah & Mohammed Akib, Noor Adelyna, 2021, Ichthyofauna of Sungai Merbok Mangrove Forest Reserve, northwest Peninsular Malaysia, and its adjacent marine waters, pp. 601-631 in Check List 17 (2) on page 607, DOI: 10.15560/17.2.601
Upper estimate of martingale dimension for self-similar fractals
Creators: name: Hino, Masanori
Publisher: name: arXiv
Year: 2012
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60G44, 28A80, 31C25, 60J60

description: We study upper estimates of the martingale dimension $d_m$ of diffusion processes associated with strong local Dirichlet forms. By applying a general strategy to self-similar Dirichlet forms on self-similar fractals, we prove that $d_m=1$ for natural diffusions on post-critically finite self-similar sets and that $d_m$ is dominated by the spectral dimension for the Brownian motion on Sierpinski carpets.
description: 49 pages, 7 figures; minor revision with adding a reference
Mooney face stimuli for visual perception research
Creators: name: Schwiedrzik, Caspar M.
name: Melloni, Lucia
name: Schurger, Aaron
Publisher: name: Columbia University
Year: 2018
Subjects: Sensory stimulation
Neurosciences--Research
Cognitive psychology--Research

description: In 1957, Craig Mooney published a set of human face stimuli to study perceptual closure: the formation of a coherent percept on the basis of minimal visual information. Images of this type, now known as “Mooney faces”, are widely used in cognitive psychology and neuroscience because they offer a means of inducing variable perception with constant visuo-spatial characteristics (they are often not perceived as faces if viewed upside down). Mooney’s original set of 40 stimuli has been employed in several studies. However, it is often necessary to use a much larger stimulus set. We created a new set of over 500 Mooney faces and tested them on a cohort of human observers. We present the results of our tests here, and make the stimuli freely available via the internet. Our test results can be used to select subsets of the stimuli that are most suited for a given experimental purpose.
Hybrid classical integrability in squashed sigma models
Creators: name: Kawaguchi, Io
name: Yoshida, Kentaroh
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We show that SU(2)_L Yangian and q-deformed SU(2)_R symmetries are realized in a two-dimensional sigma model defined on a three-dimensional squashed sphere. These symmetries enable us to develop the two descriptions to describe its classical dynamics, 1) rational and 2) trigonometric descriptions. The former 1) is based on the SU(2)_L symmetry and the latter 2) comes from the broken SU(2)_R symmetry. Each of the Lax pairs constructed in both ways leads to the same equations of motion. The two descriptions are related one another through a non-local map.
description: 12 pages, LaTeX, typos corrected and references added, further clarification added
Numerical approximation and simulation of the stochastic wave equation on the sphere
Creators: name: Cohen, David
name: Lang, Annika
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60H15, 60H35, 65C30, 60G15, 60G60, 60G17, 33C55, 41A25

description: Solutions to the stochastic wave equation on the unit sphere are approximated by spectral methods. Strong, weak, and almost sure convergence rates for the proposed numerical schemes are provided and shown to depend only on the smoothness of the driving noise and the initial conditions. Numerical experiments confirm the theoretical rates. The developed numerical method is extended to stochastic wave equations on higher-dimensional spheres and to the free stochastic Schrödinger equation on the unit sphere.
description: 26 pages, 7 figures