cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Integrated omics unveil the secondary metabolic landscape of a basal dinoflagellate
Creators: name: Beedessee, Girish
name: Kubota, Takaaki
name: Arimoto, Asuka
name: Nishitsuji, Koki
name: Waller, Ross F.
name: Hisata, Kanako
name: Yamasaki, Shinichi
name: Satoh, Noriyuki
name: Kobayashi, Jun’ichi
name: Shoguchi, Eiichi
Publisher: name: Apollo - University of Cambridge Repository
Year: 2020
Subjects: Research Article
Polyketide synthases
Harmful algal blooms
Dinoflagellates
Iso-Seq
Duplication
Amphidinium

description: Abstract: Background: Some dinoflagellates cause harmful algal blooms, releasing toxic secondary metabolites, to the detriment of marine ecosystems and human health. Our understanding of dinoflagellate toxin biosynthesis has been hampered by their unusually large genomes. To overcome this challenge, for the first time, we sequenced the genome, microRNAs, and mRNA isoforms of a basal dinoflagellate, Amphidinium gibbosum, and employed an integrated omics approach to understand its secondary metabolite biosynthesis. Results: We assembled the ~ 6.4-Gb A. gibbosum genome, and by probing decoded dinoflagellate genomes and transcriptomes, we identified the non-ribosomal peptide synthetase adenylation domain as essential for generation of specialized metabolites. Upon starving the cells of phosphate and nitrogen, we observed pronounced shifts in metabolite biosynthesis, suggestive of post-transcriptional regulation by microRNAs. Using Iso-Seq and RNA-seq data, we found that alternative splicing and polycistronic expression generate different transcripts for secondary metabolism. Conclusions: Our genomic findings suggest intricate integration of various metabolic enzymes that function iteratively to synthesize metabolites, providing mechanistic insights into how dinoflagellates synthesize secondary metabolites, depending upon nutrient availability. This study provides insights into toxin production associated with dinoflagellate blooms. The genome of this basal dinoflagellate provides important clues about dinoflagellate evolution and overcomes the large genome size, which has been a challenge previously.
Relativistic Shock Waves and Mach Cones in Viscous Gluon Matter
Creators: name: Bouras, Ioannis
name: Molnár, Etele
name: Niemi, Harri
name: Xu, Zhe
name: El, Andrej
name: Fochler, Oliver
name: Lauciello, Francesco
name: Greiner, Carsten
name: Rischke, Dirk H.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: To investigate the formation and the propagation of relativistic shock waves in viscous gluon matter we solve the relativistic Riemann problem using a microscopic parton cascade. We demonstrate the transition from ideal to viscous shock waves by varying the shear viscosity to entropy density ratio $η/s$. Furthermore we compare our results with those obtained by solving the relativistic causal dissipative fluid equations of Israel and Stewart (IS), in order to show the validity of the IS hydrodynamics. Employing the parton cascade we also investigate the formation of Mach shocks induced by a high-energy gluon traversing viscous gluon matter. For $η/s = 0.08$ a Mach cone structure is observed, whereas the signal smears out for $η/s \geq 0.32$.
description: 6 pages, 4 figures; To appear in the proceedings of the 26th Winter Workshop on Nuclear Dynamics (2010).
Arem, a Vietic Language
Creators: name: Ferlus, Michel
Publisher: name: Mon-Khmer Studies Journal
Year: 2014
Subjects: subject: aem, ptk, vie
subject: Vietic languages, lexicon, phonology

description: The paper reports on the state of knowledge of Arem, a small endangeredlanguage of the Vietic branch of Austroasiatic. Special attention is paid to thesynchronic and diachronic phonology, which display many remarkable andhighly significant features. The paper is richly illustrated with lexical examples.
Driving denaturation: Nanoscale thermal transport as a probe of DNA melting
Creators: name: Velizhanin, Kirill A.
name: Chien, Chih-Chun
name: Dubi, Yonatan
name: Zwolak, Michael
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: DNA denaturation has long been a subject of intense study due to its relationship to DNA transcription and its fundamental importance as a nonlinear, structural transition. Many aspects of this phenomenon, however, remain poorly understood. Existing models fit quite well with experimental results on the fraction of unbound base pairs versus temperature. Yet, these same models give incorrect results for other essential quantities. For example, the predicted base pair fluctuation timescales - relevant to transcription - are orders of magnitude different from those observed experimentally. Here, we demonstrate that nanoscale thermal transport can serve as a sensitive probe of the underlying microscopic mechanisms responsible for the dynamics of DNA denaturation. Specifically, we show that the heat transport properties of DNA are altered significantly and abruptly as it denaturates, and this alteration encodes detailed information on the dynamics of thermal fluctuations and their interaction along the chain. This finding allows for the unambiguous discrimination between models of DNA denaturation. Measuring the thermal conductance will thus shed new light on the nature of this important molecule.
description: 7 pages, 2 figures (revised version) Accepted for publication in Physical Review E, Rapid Communications
T lymphocyte senescence is attenuated in Parkinson’s disease
Creators: name: Kouli, Antonina
name: Jensen, Melanie
name: Papastavrou, Vanesa
name: Scott, Kirsten M.
name: Kolenda, Claire
name: Parker, Craig
name: Solim, Imtiaz H.
name: Camacho, Marta
name: Martin-Ruiz, Carmen
name: Williams-Gray, Caroline H.
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: Research
Parkinson’s disease
Immunosenescence
T lymphocytes
Ageing markers

description: Abstract: Background: Immune involvement is well-described in Parkinson’s disease (PD), including an adaptive T lymphocyte response. Given the increasing prevalence of Parkinson’s disease in older age, age-related dysregulation of T lymphocytes may be relevant in this disorder, and we have previously observed changes in age-associated CD8+ T cell subsets in mid-stage PD. This study aimed to further characterise T cell immunosenescence in newly diagnosed PD patients, including shifts in CD4+ and CD8+ subpopulations, and changes in markers of cellular ageing in CD8+ T lymphocytes. Methods: Peripheral blood mononuclear cells were extracted from the blood of 61 newly diagnosed PD patients and 63 age- and sex-matched controls. Flow cytometric analysis was used for immunophenotyping of CD8+ and CD4+ lymphocyte subsets, and analysis of recent thymic emigrant cells. Telomere length within CD8+ T lymphocytes was assessed, as well as the expression of the telomerase reverse transcriptase enzyme (hTERT), and the cell-ageing markers p16INK4a and p21CIP1/Waf1. Results: The number of CD8+ TEMRA T cells was found to be significantly reduced in PD patients compared to controls. The expression of p16INK4a in CD8+ lymphocytes was also lower in patients versus controls. Chronic latent CMV infection was associated with increased senescent CD8+ lymphocytes in healthy controls, but this shift was less apparent in PD patients. Conclusions: Taken together, our data demonstrate a reduction in CD8+ T cell replicative senescence which is present at the earliest stages of Parkinson’s disease.
Enumerating odd-degree hyperelliptic curves and abelian surfaces over $\mathbb{P}^1$
Creators: name: Han, Changho
name: Park, Jun-Yong
Publisher: name: arXiv
Year: 2020
Subjects: subject: Algebraic Geometry (math.AG)
subject: Algebraic Topology (math.AT)
subject: Number Theory (math.NT)
subject: FOS: Mathematics

description: Given asymptotic counts in number theory, a question of Venkatesh asks what is the topological nature of lower order terms. We consider the arithmetic aspect of the inertia stack of an algebraic stack over finite fields to partially answer this question. Subsequently, we acquire new sharp enumerations on quasi-admissible odd-degree hyperelliptic curves over $\mathbb{F}_q(t)$ ordered by bounded discriminant height.
description: 40 pages, expository changes and added the arithmetic geometry of inertia stacks of algebraic stacks. Comments welcome!
Conception and FPGA implementation of IEEE 802.11s mesh network MAC layer transmitter
Creators: name: Chaari, Lamia
name: Ayadi, Rim
name: Kamoun, Lotfi
Publisher: name: arXiv
Year: 2010
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: This paper proposes, a hardware implementation of Wireless Mesh Networks (WMN) medium Access Controller (MAC) layer transmitter. In the literature a lot of works are focused on WMN routing protocol as well as performance analysis and software integration of WMN units, however few works deals with WMN hardware implementation. In this field our contribution is to conceive and to implements on FPGA a WMN MAC transmitter module. Our implementation, written in hardware description language (HDL) is based on the IEEE 802.11 s standard. The hardware implementation retains a good performance in speed.
description: Lamia Chaari, Rim Ayadi and Lotfi Kamoun, "Conception and FPGA implementation of IEEE 802.11s mesh network MAC layer transmitter"
Multimodal Controller for Generative Models
Creators: name: Diao, Enmao
name: Ding, Jie
name: Tarokh, Vahid
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Class-conditional generative models are crucial tools for data generation from user-specified class labels. Existing approaches for class-conditional generative models require nontrivial modifications of backbone generative architectures to model conditional information fed into the model. This paper introduces a plug-and-play module named `multimodal controller' to generate multimodal data without introducing additional learning parameters. In the absence of the controllers, our model reduces to non-conditional generative models. We test the efficacy of multimodal controllers on CIFAR10, COIL100, and Omniglot benchmark datasets. We demonstrate that multimodal controlled generative models (including VAE, PixelCNN, Glow, and GAN) can generate class-conditional images of significantly better quality when compared with conditional generative models. Moreover, we show that multimodal controlled models can also create novel modalities of images.
Nature of the spin liquid state of the Hubbard model on honeycomb lattice
Creators: name: Clark, B. K.
name: Abanin, D. A.
name: Sondhi, S. L.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Recent numerical work (Nature 464, 847 (2010)) indicates the existence of a spin liquid phase (SL) that intervenes between the antiferromagnetic and semimetallic phases of the half filled Hubbard model on a honeycomb lattice. To better understand the nature of this exotic phase, we study the quantum $J_1-J_2$ spin model on the honeycomb lattice, which provides an effective description of the Mott insulating region of the Hubbard model. Employing the variational Monte Carlo approach, we analyze the phase diagram of the model, finding a phase transition between antiferromagnet and an unusual $Z_2$ SL state at $J_2/J_1\approx 0.08$, which we identify as the SL phase of the Hubbard model. At higher $J_2/J_1\gtrsim 0.3$ we find a transition to a dimerized state with spontaneously broken rotational symmetry.
description: 5 pages, 6 figures
title: Der emanzipierte Patient - Eine empirische Untersuchung zum Einfluss des Arzt-Patienten-Gesprächs auf das Informationsverhalten im Web
Creators: name: Lein, Celina
Publisher: name: Hochschule Hannover
Year: 2021
Subjects: subject: 380 Handel, Kommunikation, Verkehr

description: Im Rahmen dieser Bachelorarbeit wird das Feld des Arzt-Patienten-Gesprächs und die Forschung zum digitalen Informationsverhalten verknüpft. Dabei soll empirisch überprüft werden, welche Faktoren des Gesprächs zwischen Arzt und Patient sich auf die Online-Informationssuche auswirken.
Laparoscopic vs. open feeding jejunostomy insertion in oesophagogastric cancer
Creators: name: Mastoridis, Sotiris
name: Bracalente, Giada
name: Hanganu, Christine-Bianca
name: Neccia, Michela
name: Giuliani, Antonio
name: Gillies, Richard
name: Marshall, Robert
name: Maynard, Nicholas
name: Sgromo, Bruno
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: Research Article
Visceral and general surgery
Laparoscopic
Feeding
Jejunostomy
Oesophagogastric
Cancer

description: Abstract: Background: Jejunal feeding is an invaluable method by which to improve the nutritional status of patients undergoing neoadjuvant and surgical treatment of oesophageal malignancies. However, the insertion of a feeding jejunostomy can cause significant postoperative morbidity. The aim of this study is to compare the outcomes of patients undergoing placement of feeding jejunostomy by conventional laparotomy with an alternative laparoscopic approach. Methods: A retrospective review of data prospectively collected at the Oxford Oesophagogastric Centre between August 2017 and July 2019 was performed including consecutive patients undergoing feeding jejunostomy insertion. Results: In the study period, 157 patients underwent jejunostomy insertion in the context of oesophageal cancer therapy, 126 (80%) by open technique and 31 (20%) laparoscopic. Pre-operative demographic and nutritional characteristics were broadly similar between groups. In the early postoperative period jejunostomy-associated complications were noted in 54 cases (34.4%) and were significantly more common among those undergoing open as compared with laparoscopic insertion (38.1% vs. 19.3%, P = 0.049). Furthermore, major complications were more common among those undergoing open insertion, whether as a stand-alone or at the time of staging laparoscopy (n = 11/71), as compared with insertion at the time of oesophagectomy (n = 3/86, P = 0.011). Conclusions: This report represents the largest to our knowledge single-centre comparison of open vs. laparoscopic jejunostomy insertion in patients undergoing oesophagectomy in the treatment of gastroesophageal malignancy. We conclude that the laparoscopic jejunostomy insertion technique described represents a safe and effective approach to enteral access which may offer superior outcomes to conventional open procedures.
Generalized Zeta Function Regularization and the Multiplicative Anomaly
Creators: name: Cognola, G.
name: Zerbini, S.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: A brief survey of the zeta function regularization and multiplicative anomaly issues when the associated zeta function of fluctuation operator is the regular at the origin (regular case) as well as when it is singular at the origin (singular case) is presented. In the singular case, new results for the multiplicative anomaly are presented
description: 10 pages, submitted to the volume "Cosmology, Quantum Vacuum, and Zeta Functions", in honour of Professor Emilio Elizalde on the occasion of his 60th birthday
Detailed cluster lensing profiles at large radii and the impact on cluster weak lensing studies
Creators: name: Oguri, Masamune
name: Hamana, Takashi
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Using a large set of ray-tracing in N-body simulations, we examine lensing profiles around massive dark haloes in detail, with a particular emphasis on the profile at around the virial radii. We compare radial convergence profiles, which are measured accurately in the ray-tracing simulations by stacking many dark haloes, with our simple analytic model predictions. Our analytic models consist of a main halo, which is modelled by the Navarro-Frenk-White (NFW) density profile with three different forms of the truncation, plus the correlated matter (2-halo term) around the main halo. We find that the smoothly truncated NFW profile best reproduces the simulated lensing profiles, out to more than 10 times the virial radius. We then use this analytic model to investigate potential biases in cluster weak lensing studies in which a single, untruncated NFW component is usually assumed in interpreting observed signals. We find that cluster masses, inferred by fitting reduced tangential shear profiles with the NFW profile, tend to be underestimated by ~5-10% if fitting is performed out to ~10'-30'. In contrast, the concentration parameter is overestimated typically by ~20% for the same fitting range. We also investigate biases in computing the signal-to-noise ratio of weak lensing mass peaks, finding them to be <4% for significant mass peaks. In the Appendices, we provide useful formulae for the smoothly truncated NFW profile.
description: 11 pages, 7 figures, accepted for publication in MNRAS; fixed typo in eq. (A3)
Human Motion Transfer with 3D Constraints and Detail Enhancement
Creators: name: Sun, Yang-Tian
name: Fu, Qian-Cheng
name: Jiang, Yue-Ren
name: Liu, Zitao
name: Lai, Yu-Kun
name: Fu, Hongbo
name: Gao, Lin
Publisher: name: arXiv
Year: 2020
Subjects: subject: Graphics (cs.GR)
subject: FOS: Computer and information sciences

description: We propose a new method for realistic human motion transfer using a generative adversarial network (GAN), which generates a motion video of a target character imitating actions of a source character, while maintaining high authenticity of the generated results. We tackle the problem by decoupling and recombining the posture information and appearance information of both the source and target characters. The innovation of our approach lies in the use of the projection of a reconstructed 3D human model as the condition of GAN to better maintain the structural integrity of transfer results in different poses. We further introduce a detail enhancement net to enhance the details of transfer results by exploiting the details in real source frames. Extensive experiments show that our approach yields better results both qualitatively and quantitatively than the state-of-the-art methods.
Allenarsi giocando: Il piacere della fatica
Creators: name: Canepa, Mosè
Publisher: name: Scuola Universitaria della Svizzera Italiana (SUPSI)
Year: 2018

description: INTRODUZIONE A causa dell’alto tasso di sedentarietà tra gli adolescenti la scuola deve intervenire in chiave preventiva per la promozione della salute. L’educazione fisica ha un potenziale enorme per intervenire in questo ambito, ma per ottenere risultati deve pensare anche come produrre un effetto che abbia riscontri al di fuori del contesto scolastico. Attraverso questo studio si investigheranno alcuni aspetti della logica interna delle situazioni motorie per comprendere quali caratteristiche possono essere più motivanti e quindi con lo scopo d’invogliare gli allievi a praticare dell’attività fisica. METODOLOGIA Due classi, una di seconda media e una di quarta, per un totale di 33 allievi, devono affrontare tre situazioni motorie in tre lezioni distinte. Le situazioni motorie sono state sviluppate partendo dagli allenamenti di corsa intervallati e sono differenziate tra di loro per la struttura relazionale della logica interna: attività psicomotoria (1), attività sociomotoria con partner (2) e sociomotoria con avversario (3). Un questionario sottoposto alla fine di ogni lezione permetterà di comprendere il legame tra la situazione motoria e l’intensità delle emozioni positive e negative provate durante l’esercizio, il desiderio di continuare l’esercizio (DCE), l’intensità dello sforzo percepito (RPE) e infine la motivazione (DCE/RPE). RISULTATI Le emozioni positive sono significativamente più intense per le situazioni psicomotoria e sociomotoria con partner rispetto a quella sociomotoria con avversario (P < 0.01 e rispettivamente P < 0.05). L’attività sociomotoria con avversario è quella che suscita più emozioni negative. L’ RPE è significativamente più elevata del 10% per le due situazioni sociomotorie rispetto a quella psicomotoria (P < 0.05). La motivazione è significativamente più elevata per l’attività sociomotoria con partner del 27% rispetto a quella con avversario (P < 0.05). DISCUSSIONE E CONCLUSIONE Il presente studio ha permesso di dimostrare che per degli allievi di 12-15 anni, la situazione motoria più indicata per motivare gli allievi a cimentarsi nella corsa intervallata mentendo un’intensità elevata, è quella sociomotoria con partner. Relatore: Giacomo Crivelli. Materia: Educazione fisica
Are you looking at me? : an objective state of mind reduces sensitivity to other's emotional expressions
Creators: name: Liu, Manlu
Publisher: name: University of British Columbia
Year: 2021

description: An objective state of mind refers to a mental state in which people perceive themselves as the object of another’s observation. Previous research has shown that this state affects people’s metacognitive process, emotional experience, and social behavior. An objective mental state often arises during everyday social interaction, but few studies have investigated how it influences one’s social perception during an encounter. Here we examine how the perception of others’ emotion is influenced by triggering an objective state of mind. We developed an online experiment using webcams, questions, and pre-programmed conversations to manipulate participants’ mental states. We then measured their accuracy in reading the emotional expressions of people they believed they were interacting with. Three conditions were compared. In the Evaluated condition, participants were asked to classify the emotional expressions of two study assistants, after being informed that one of the assistants might select them as a partner in a competitive game. In the Evaluating condition, different participants classified the emotional expressions of the same assistants, but this time believing that they would be able to select one assistant as a game partner. In the Neutral condition, the same emotion classification task was performed, but participants were not given any other instructions. The results showed that participants in the Evaluated condition were significantly less accurate in classifying emotions than in the other two conditions. We interpret this finding as supporting the view that an objective mental state reduces the ability to read other’s emotional cues. We discuss possible mechanisms by which this may occur, including increased stress, divided attention, and the role of latent imitation in forming empathy for others.
Dielectric secondary relaxation of water in aqueous binary glass-formers
Creators: name: Sjöström, Johan
name: Mattsson, Johan
name: Bergman, Rikard
name: Johansson, Erik
name: Josefsson, Karin
name: Svantesson, David
name: Swenson, Jan
Publisher: name: arXiv
Year: 2010
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: The dielectric relaxation of water in glassy aqueous binary mixtures exhibits an Arrhenius behaviour with a nearly universal activation energy. We here demonstrate that its characteristic relaxation time follows a remarkably general functional dependence on the weight fraction of water for a wide range of molecular systems.
Understanding the Perceived Quality of Video Predictions
Creators: name: Somraj, Nagabhushan
name: Kashi, Manoj Surya
name: Arun, S. P.
name: Soundararajan, Rajiv
Publisher: name: arXiv
Year: 2020
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: The study of video prediction models is believed to be a fundamental approach to representation learning for videos. While a plethora of generative models for predicting the future frame pixel values given the past few frames exist, the quantitative evaluation of the predicted frames has been found to be extremely challenging. In this context, we study the problem of quality assessment of predicted videos. We create the Indian Institute of Science Predicted Videos Quality Assessment (IISc PVQA) Database consisting of 300 videos, obtained by applying different prediction models on different datasets, and accompanying human opinion scores. We collected subjective ratings of quality from 50 human participants for these videos. Our subjective study reveals that human observers were highly consistent in their judgments of quality of predicted videos. We benchmark several popularly used measures for evaluating video prediction and show that they do not adequately correlate with these subjective scores. We introduce two new features to effectively capture the quality of predicted videos, motion-compensated cosine similarities of deep features of predicted frames with past frames, and deep features extracted from rescaled frame differences. We show that our feature design leads to state of the art quality prediction in accordance with human judgments on our IISc PVQA Database. The database and code are publicly available on our project website: https://nagabhushansn95.github.io/publications/2020/pvqa
description: Project website: https://nagabhushansn95.github.io/publications/2020/pvqa.html. Accepted in SPIC
Dilations of unitary tuples
Creators: name: Gerhold, Malte
name: Pandey, Satish K.
name: Shalit, Orr
name: Solel, Baruch
Publisher: name: arXiv
Year: 2020
Subjects: subject: Operator Algebras (math.OA)
subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 47A13, 46L54

description: We study the space of all $d$-tuples of unitaries $u=(u_1,\ldots, u_d)$ using dilation theory and matrix ranges. Given two $d$-tuples $u$ and $v$ generating C*-algebras $\mathcal A$ and $\mathcal B$, we seek the minimal dilation constant $c=c(u,v)$ such that $u\prec cv$, by which we mean that $u$ is a compression of some $*$-isomorphic copy of $cv$. This gives rise to a metric \[ d_D(u,v)=\log\max\{c(u,v),c(v,u)\} \] on the set of equivalence classes of $*$-isomorphic tuples of unitaries. We also consider the metric \[ d_{HR}(u,v)=\inf\left\{\|u'-v'\|:u',v'\in B(H)^d, u'\sim u\textrm{ and } v'\sim v\right\}, \] and we show the inequality \[ d_{HR}(u,v)\leq K d_D(u,v)^{1/2}. \] Let $u_Θ$ be the universal unitary tuple $(u_1,\ldots,u_d)$ satisfying $u_\ell u_k=e^{iθ_{k,\ell}} u_k u_\ell$, where $Θ=(θ_{k,\ell})$ is a real antisymmetric matrix. We find that $c(u_Θ, u_{Θ'})\leq e^{\frac{1}{4}\|Θ-Θ'\|}$. From this we recover the result of Haagerup-Rordam and Gao that there exists a map $Θ\mapsto U(Θ)\in B(H)^d$ such that $U(Θ)\sim u_Θ$ and \[ \|U(Θ)-U({Θ'})\|\leq K\|Θ-Θ'\|^{1/2}. \] Of special interest are: the universal $d$-tuple of noncommuting unitaries ${\mathrm u}$, the $d$-tuple of free Haar unitaries $u_f$, and the universal $d$-tuple of commuting unitaries $u_0$. We obtain the bounds \[ 2\sqrt{1-\frac{1}{d}}\leq c(u_f,u_0)\leq 2\sqrt{1-\frac{1}{2d}}. \] From this, we recover Passer's upper bound for the universal unitaries $c({\mathrm u},u_0)\leq\sqrt{2d}$. In the case $d=3$ we obtain the new lower bound $c({\mathrm u},u_0)\geq 1.858$ improving on the previously known lower bound $c({\mathrm u},u_0)\geq\sqrt{3}$.
description: 31 pages. A few minor corrections have been made and a new appendix (Appendix B) has been added. To appear in Journal of the London Mathematical Society
Emotional and behavioural problems in Lithuanian children: data bases of two longitudinal and two cross-sectional studies
Creators: name: Jusiene, Roma
Publisher: name: Zenodo
Year: 2025

description: Presented at the Conference on Data Sharing and Secondary Analysis in Child and Youth Wellbeing Research, organised within the COORDINATE project, held in Zagreb from 9th to 10th December 2024. The main objective of the conference was to showcase existing efforts in secondary data analysis for research and policy development, and to discuss the benefits and challenges of data-sharing practices in the field of child and youth wellbeing.
Uniformly Positive Entropy of Induced Transformations
Creators: name: Bernardes, Nilson C.
name: Darji, Udayan B.
name: Vermersch, Rômulo M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: Primary 37B40, Secondary 28A33, 60B10, 54B20

description: Let $(X,T)$ be a topological dynamical system consisting of a compact metric space $X$ and a continuous surjective map $T : X \to X$. By using local entropy theory, we prove that $(X,T)$ has uniformly positive entropy if and only if so does the induced system $(\cM(X),\wt{T})$ on the space of Borel probability measures endowed with the weak$^*$ topology. This result can be seen as a version for the notion of uniformly positive entropy of the corresponding result for topological entropy due to Glasner and Weiss.
description: To apper in ETDS
Similarity Join Size Estimation using Locality Sensitive Hashing
Creators: name: Lee, Hongrae
name: Ng, Raymond T.
name: Shim, Kyuseok
Publisher: name: arXiv
Year: 2011
Subjects: subject: Databases (cs.DB)
subject: Data Structures and Algorithms (cs.DS)
subject: FOS: Computer and information sciences

description: Similarity joins are important operations with a broad range of applications. In this paper, we study the problem of vector similarity join size estimation (VSJ). It is a generalization of the previously studied set similarity join size estimation (SSJ) problem and can handle more interesting cases such as TF-IDF vectors. One of the key challenges in similarity join size estimation is that the join size can change dramatically depending on the input similarity threshold. We propose a sampling based algorithm that uses the Locality-Sensitive-Hashing (LSH) scheme. The proposed algorithm LSH-SS uses an LSH index to enable effective sampling even at high thresholds. We compare the proposed technique with random sampling and the state-of-the-art technique for SSJ (adapted to VSJ) and demonstrate LSH-SS offers more accurate estimates at both high and low similarity thresholds and small variance using real-world data sets.
description: VLDB2011
Tight relative $t$-designs on two shells in hypercubes, and Hahn and Hermite polynomials
Creators: name: Bannai, Eiichi
name: Bannai, Etsuko
name: Tanaka, Hajime
name: Zhu, Yan
Publisher: name: arXiv
Year: 2020
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05B30, 05E30, 33C45

description: Relative $t$-designs in the $n$-dimensional hypercube $\mathcal{Q}_n$ are equivalent to weighted regular $t$-wise balanced designs, which generalize combinatorial $t$-$(n,k,λ)$ designs by allowing multiple block sizes as well as weights. Partly motivated by the recent study on tight Euclidean $t$-designs on two concentric spheres, in this paper we discuss tight relative $t$-designs in $\mathcal{Q}_n$ supported on two shells. We show under a mild condition that such a relative $t$-design induces the structure of a coherent configuration with two fibers. Moreover, from this structure we deduce that a polynomial from the family of the Hahn hypergeometric orthogonal polynomials must have only integral simple zeros. The Terwilliger algebra is the main tool to establish these results. By explicitly evaluating the behavior of the zeros of the Hahn polynomials when they degenerate to the Hermite polynomials under an appropriate limit process, we prove a theorem which gives a partial evidence that the non-trivial tight relative $t$-designs in $\mathcal{Q}_n$ supported on two shells are rare for large $t$.
description: 37 pages
title: Ð Ð°Ð·ÑÐ°Ð±Ð¾ÑÐºÐ° ÐºÐ¾Ð¼Ð¿Ð¾Ð·Ð¸ÑÐ¸Ð¾Ð½Ð½Ð¾Ð³Ð¾ ÑÐµÑÐµÐ½Ð¸Ñ Ð¸ Ð²ÑÐ¿Ð¾Ð»Ð½ÐµÐ½Ð¸Ðµ Ð² Ð¼Ð°ÑÐµÑÐ¸Ð°Ð»Ðµ Ð´ÐµÐºÐ¾ÑÐ°ÑÐ¸Ð²Ð½Ð¾Ð³Ð¾ Ð¸Ð·Ð´ÐµÐ»Ð¸Ñ Ð² ÑÐµÑ Ð½Ð¸ÐºÐµ Ð³Ð¾ÑÑÑÐµÐ³Ð¾ ÑÐ¿Ð»Ð¾ÑÐ½Ð¾Ð³Ð¾ ÑÐ¼Ð°Ð»Ð¸ÑÐ¾Ð²Ð°Ð½Ð¸Ñ Ð¼ÐµÑÐ°Ð»Ð»Ð°. ÐÐ¾Ð»ÑÑÐµÐ½Ð¸Ðµ Ð½Ð¾Ð²ÑÑ ÑÐ²ÐµÑÐ¾Ð² Ð¿ÑÑÐµÐ¼ ÑÐ¼ÐµÑÐµÐ½Ð¸Ñ ÑÐ°Ð·Ð»Ð¸ÑÐ½ÑÑ Ð²Ð¸Ð´Ð¾Ð² Ð¿ÑÐ¾Ð·ÑÐ°ÑÐ½Ð¾Ð¹ ÑÐ¼Ð°Ð»Ð¸
title: Ð²ÑÐ¿ÑÑÐºÐ½Ð°Ñ ÐºÐ²Ð°Ð»Ð¸ÑÐ¸ÐºÐ°ÑÐ¸Ð¾Ð½Ð½Ð°Ñ ÑÐ°Ð±Ð¾ÑÐ° Ð±Ð°ÐºÐ°Ð»Ð°Ð²ÑÐ°
titleType: Subtitle
title: Development of a compositional solution and implementation of decorative in the material products in the technique of hot solid metal enameling. Getting new colors by mixing different types of transpa
Creators: name: Ð¡Ð¸Ð»Ð°ÐµÐ²Ð°, ÐÐ²Ð³ÐµÐ½Ð¸Ñ
Publisher: name: Ð¡Ð°Ð½ÐºÑ-ÐÐµÑÐµÑÐ±ÑÑÐ³ÑÐºÐ¸Ð¹ Ð¿Ð¾Ð»Ð¸ÑÐµÑÐ½Ð¸ÑÐµÑÐºÐ¸Ð¹ ÑÐ½Ð¸Ð²ÐµÑÑÐ¸ÑÐµÑ ÐÐµÑÑÐ° ÐÐµÐ»Ð¸ÐºÐ¾Ð³Ð¾
Year: 2022
Subjects: Ð¸ÑÐºÑÑÑÑÐ²Ð¾ Ð¸ ÑÐµÐ»Ð¾Ð²ÐµÐº
Ñ ÑÐ´Ð¾Ð¶ÐµÑÑÐ²ÐµÐ½Ð½Ð¾Ðµ Ð¿ÑÐ¾ÐµÐºÑÐ¸ÑÐ¾Ð²Ð°Ð½Ð¸Ðµ
Ð³Ð¾ÑÑÑÐ°Ñ ÑÐ¼Ð°Ð»Ñ
ÑÐ¼ÐµÑÐµÐ½Ð¸Ðµ Ð¿ÑÐ¾Ð·ÑÐ°ÑÐ½ÑÑ ÑÐ¼Ð°Ð»ÐµÐ¹
Ñ Ð¸Ð¼Ð¸ÑÐµÑÐºÐ¾Ðµ ÑÑÐ°Ð²Ð»ÐµÐ½Ð¸Ðµ
art and man
artistic design
hot enamel
mixing of transparent enamels
chemical etching

description: Ð¢ÐµÐ¼Ð° Ð²ÑÐ¿ÑÑÐºÐ½Ð¾Ð¹ ÐºÐ²Ð°Ð»Ð¸ÑÐ¸ÐºÐ°ÑÐ¸Ð¾Ð½Ð½Ð¾Ð¹ ÑÐ°Ð±Ð¾ÑÑ: Â«Ð Ð°Ð·ÑÐ°Ð±Ð¾ÑÐºÐ° ÐºÐ¾Ð¼Ð¿Ð¾Ð·Ð¸ÑÐ¸Ð¾Ð½Ð½Ð¾Ð³Ð¾ ÑÐµÑÐµÐ½Ð¸Ñ Ð¸ Ð²ÑÐ¿Ð¾Ð»Ð½ÐµÐ½Ð¸Ðµ Ð² Ð¼Ð°ÑÐµÑÐ¸Ð°Ð»Ðµ Ð´ÐµÐºÐ¾ÑÐ°ÑÐ¸Ð²Ð½Ð¾Ð³Ð¾ Ð¸Ð·Ð´ÐµÐ»Ð¸Ñ Ð² ÑÐµÑÐ½Ð¸ÐºÐµ Ð³Ð¾ÑÑÑÐµÐ³Ð¾ ÑÐ¿Ð»Ð¾ÑÐ½Ð¾Ð³Ð¾ ÑÐ¼Ð°Ð»Ð¸ÑÐ¾Ð²Ð°Ð½Ð¸Ñ Ð¼ÐµÑÐ°Ð»Ð»Ð°. ÐÐ¾Ð»ÑÑÐµÐ½Ð¸Ðµ Ð½Ð¾Ð²ÑÑ ÑÐ²ÐµÑÐ¾Ð² Ð¿ÑÑÐµÐ¼ ÑÐ¼ÐµÑÐµÐ½Ð¸Ñ ÑÐ°Ð·Ð»Ð¸ÑÐ½ÑÑ Ð²Ð¸Ð´Ð¾Ð² Ð¿ÑÐ¾Ð·ÑÐ°ÑÐ½Ð¾Ð¹ ÑÐ¼Ð°Ð»Ð¸Â». ÐÐ°Ð½Ð½Ð°Ñ ÑÐ°Ð±Ð¾ÑÐ° Ð¿Ð¾ÑÐ²ÑÑÐµÐ½Ð° ÑÐ¾Ð·Ð´Ð°Ð½Ð¸Ñ ÑÑÐ´Ð¾Ð¶ÐµÑÑÐ²ÐµÐ½Ð½Ð¾Ð³Ð¾ ÑÑÐ°Ð½ÐºÐ¾Ð²Ð¾Ð³Ð¾ Ð¸Ð·Ð´ÐµÐ»Ð¸Ñ, Ð¿ÑÑÐµÐ¼ ÑÐ¸Ð¼Ð¸ÑÐµÑÐºÐ¾Ð³Ð¾ ÑÑÐ°Ð²Ð»ÐµÐ½Ð¸Ñ Ð¸ Ð³Ð¾ÑÑÑÐµÐ³Ð¾ ÑÐ¼Ð°Ð»Ð¸ÑÐ¾Ð²Ð°Ð½Ð¸Ñ Ð¼ÐµÑÐ°Ð»Ð»Ð°. Ð£Ð¿Ð¾Ñ Ð² ÑÐ°Ð±Ð¾ÑÐµ Ñ Ð¼Ð°ÑÐµÑÐ¸Ð°Ð»Ð¾Ð¼ ÑÐ´ÐµÐ»Ð°Ð½ Ð½Ð° Ð¸ÑÑÐ»ÐµÐ´Ð¾Ð²Ð°Ð½Ð¸Ðµ Ð²Ð¾Ð·Ð¼Ð¾Ð¶Ð½Ð¾ÑÑÐ¸ Ð³Ð¾ÑÑÑÐ¸Ñ Ð¿ÑÐ¾Ð·ÑÐ°ÑÐ½ÑÑ ÑÐ¼Ð°Ð»ÐµÐ¹ Ðº ÑÐ¼ÐµÑÐµÐ½Ð¸Ñ. Ð¢Ð°ÐºÐ¶Ðµ Ð²Ð°Ð¶Ð½ÑÐ¼ Ð°ÑÐ¿ÐµÐºÑÐ¾Ð¼ ÑÐ°Ð±Ð¾ÑÑ ÑÐ²Ð»ÑÐ»Ð¾ÑÑ Ð¸Ð·ÑÑÐµÐ½Ð¸Ðµ Ð¸ÑÑÐ¾ÑÐ¸Ð¸ Ð¸ÑÐºÑÑÑÑÐ² Ð¸ ÑÐ¾Ð·Ð´Ð°Ð½Ð¸Ðµ Ð½Ð° Ð¾ÑÐ½Ð¾Ð²Ðµ Ð¿Ð¾Ð»ÑÑÐµÐ½Ð½ÑÑ Ð·Ð½Ð°Ð½Ð¸Ð¹ ÐºÐ¾Ð½ÑÐµÐ¿ÑÑÐ°Ð»ÑÐ½Ð¾ Ð¸ ÑÑÐ´Ð¾Ð¶ÐµÑÑÐ²ÐµÐ½Ð½Ð¾ ÑÐµÐ½Ð½Ð¾Ð³Ð¾ Ð¸Ð·Ð´ÐµÐ»Ð¸Ñ.
description: The topic of the final qualifying work: "The development of a composite solution and the execution of a decorative product in the material in the technique of hot solid metal enameling. Obtaining new colors by mixing different types of transparent enamel". This work is devoted to the creation of an artistic easel product, by chemical etching and hot enameling. The emphasis in working with the material is made on the study of the possibilities of hot transparent enamels for mixing. Also, an important aspect of the work was the study of art history and the creation of a conceptually and artistically valuable product based on the knowledge gained.
Miniaturization of photonic waveguides by the use of left-handed materials
Creators: name: Tassin, Philippe
name: Sahyoun, Xavier
name: Veretennicoff, Irina
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We propose the use of a left-handed material in an optical waveguide structure to reduce its thickness well below the wavelength of light. We demonstrate that a layer of left-handed material, added to the cladding of a planar waveguide rather than to its core, allows for good light confinement in a subwavelength thin waveguide. We attribute the observed behavior to the change in phase evolution of electromagnetic waves in the guide. This technique can be used for the miniaturization of photonic integrated circuits.
description: 4 pages, 4 figures
Agreement in Ho
Creators: name: Choudhary, P.K.
Publisher: name: Mon-Khmer Studies Journal
Year: 2014
Subjects: subject: hoc, mai
subject: Agreement, Pro-drop, Animacy

description: The aim of this paper is to show the conditions of agreement marking in Ho, anAustroasiatic language. Pronominal clitics are attached as an agreement markeron the preverbal word, the verb and may be before or after the finite marker.The agreement morpheme allows Subject, Object, or both to be dropped. Thereis no inflectional agreement marker in Ho. The agglutinating nature of themorpheme makes North-Munda languages in general, and Ho in particular,morphologically very rich. Negation too, can host agreement clitic. Thefunction of these clitic is twofold; one is to carry the load of the NP, and the otheris to allow the NP to be dropped.
Testing the tidal alignment model of galaxy intrinsic alignment
Creators: name: Blazek, Jonathan
name: McQuinn, Matthew
name: Seljak, Uros
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Weak gravitational lensing has become a powerful probe of large-scale structure and cosmological parameters. Precision weak lensing measurements require an understanding of the intrinsic alignment of galaxy ellipticities, which can in turn inform models of galaxy formation. It is hypothesized that elliptical galaxies align with the background tidal field and that this alignment mechanism dominates the correlation between ellipticities on cosmological scales (in the absence of lensing). We use recent large-scale structure measurements from the Sloan Digital Sky Survey to test this picture with several statistics: (1) the correlation between ellipticity and galaxy overdensity, w_{g+}; (2) the intrinsic alignment auto-correlation functions; (3) the correlation functions of curl-free, E, and divergence-free, B, modes (the latter of which is zero in the linear tidal alignment theory); (4) the alignment correlation function, w_g(r_p,theta), a recently developed statistic that generalizes the galaxy correlation function to account for the angle between the galaxy separation vector and the principle axis of ellipticity. We show that recent measurements are largely consistent with the tidal alignment model and discuss dependence on galaxy luminosity. In addition, we show that at linear order the tidal alignment model predicts that the angular dependence of w_g(r_p,theta) is simply w_{g+}*cos(2*theta) and that this dependence is consistent with recent measurements. We also study how stochastic nonlinear contributions to galaxy ellipticity impact these statistics. We find that a significant fraction of the observed LRG ellipticity can be explained by alignment with the tidal field on scales >~10 h^-1 Mpc. These considerations are relevant to galaxy formation and evolution.
description: 23 pages, 5 figures, minor changes to reflect published version, including updated figures and a minor correction to the measured errors
Multimodal Generative Learning Utilizing Jensen-Shannon-Divergence
Creators: name: Sutter, Thomas M.
name: Daunhawer, Imant
name: Vogt, Julia E.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Learning from different data types is a long-standing goal in machine learning research, as multiple information sources co-occur when describing natural phenomena. However, existing generative models that approximate a multimodal ELBO rely on difficult or inefficient training schemes to learn a joint distribution and the dependencies between modalities. In this work, we propose a novel, efficient objective function that utilizes the Jensen-Shannon divergence for multiple distributions. It simultaneously approximates the unimodal and joint multimodal posteriors directly via a dynamic prior. In addition, we theoretically prove that the new multimodal JS-divergence (mmJSD) objective optimizes an ELBO. In extensive experiments, we demonstrate the advantage of the proposed mmJSD model compared to previous work in unsupervised, generative learning tasks.
description: Accepted at NeurIPS 2020, camera-ready version
Estimation of required sample size for external validation of risk models for binary outcomes
Creators: name: Pavlou, Menelaos
name: Qu, Chen
name: Omar, Rumana Z
name: Seaman, Shaun R
name: Steyerberg, Ewout W
name: White, Ian R
name: Ambler, Gareth
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: Articles
Sample size calculation
prediction model
C-statistic
discrimination
calibration

description: Risk-prediction models for health outcomes are used in practice as part of clinical decision-making, and it is essential that their performance be externally validated. An important aspect in the design of a validation study is choosing an adequate sample size. In this paper, we investigate the sample size requirements for validation studies with binary outcomes to estimate measures of predictive performance (C-statistic for discrimination and calibration slope and calibration in the large). We aim for sufficient precision in the estimated measures. In addition, we investigate the sample size to achieve sufficient power to detect a difference from a target value. Under normality assumptions on the distribution of the linear predictor, we obtain simple estimators for sample size calculations based on the measures above. Simulation studies show that the estimators perform well for common values of the C-statistic and outcome prevalence when the linear predictor is marginally Normal. Their performance deteriorates only slightly when the normality assumptions are violated. We also propose estimators which do not require normality assumptions but require specification of the marginal distribution of the linear predictor and require the use of numerical integration. These estimators were also seen to perform very well under marginal normality. Our sample size equations require a specified standard error (SE) and the anticipated C-statistic and outcome prevalence. The sample size requirement varies according to the prognostic strength of the model, outcome prevalence, choice of the performance measure and study objective. For example, to achieve an SE < 0.025 for the C-statistic, 60–170 events are required if the true C-statistic and outcome prevalence are between 0.64–0.85 and 0.05–0.3, respectively. For the calibration slope and calibration in the large, achieving SE < 0.15 would require 40–280 and 50–100 events, respectively. Our estimators may also be used for survival outcomes when the proportion of censored observations is high.
Query Expansion Based on Clustered Results
Creators: name: Liu, Ziyang
name: Natarajan, Sivaramakrishnan
name: Chen, Yi
Publisher: name: arXiv
Year: 2011
Subjects: subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: Query expansion is a functionality of search engines that suggests a set of related queries for a user-issued keyword query. Typical corpus-driven keyword query expansion approaches return popular words in the results as expanded queries. Using these approaches, the expanded queries may correspond to a subset of possible query semantics, and thus miss relevant results. To handle ambiguous queries and exploratory queries, whose result relevance is difficult to judge, we propose a new framework for keyword query expansion: we start with clustering the results according to user specified granularity, and then generate expanded queries, such that one expanded query is generated for each cluster whose result set should ideally be the corresponding cluster. We formalize this problem and show its APX-hardness. Then we propose two efficient algorithms named iterative single-keyword refinement and partial elimination based convergence, respectively, which effectively generate a set of expanded queries from clustered results that provide a classification of the original query results. We believe our study of generating an optimal query based on the ground truth of the query results not only has applications in query expansion, but has significance for studying keyword search quality in general.
description: VLDB2011
Neutron polarisation correction to triple-axis data with analytical derivations
Creators: name: Nambu, Yusuke
name: Enderle, Mechthild
name: Weber, Tobias
name: Kakurai, Kazuhisa
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Polarised neutron scattering is the method of choice to study magnetism in condensed matter. Polarised neutrons are typically very low in flux, and complex experimental configurations further reduce the count rate. Neutron polarisation corrections would therefore be needed. Here we analytically derive formulae of the corrected partial differential scattering cross-sections. The analytical method is designed for the longitudinal polarisation analysis, and the correction generally holds for time-independent polarised neutrons with a triple-axis spectrometer. We then apply the correction to recent results of our $P_x$ experiment on Y$_3$Fe$_5$O$_{12}$. Although there is a difficulty with the experimental determination of inefficiency parameters of neutron spin polarisers and flippers, the correction appears to work properly.
description: 8 pages, 2 figures
Teaching Drama: Activities to Increase the Students’ Appreciation of “An Inspector Calls”
Creators: name: Frigerio, Lisa
Publisher: name: Scuola Universitaria della Svizzera Italiana (SUPSI)
Year: 2018

description: This project aims at finding out whether there are some didactic activities which motivate students to work on the dramatic text and contribute to increase its appreciation. To reach this aim, the research investigates the effectiveness of varied didactic activities which compel students to activate different learning strategies while reading An Inspector Calls by J. B. Priestley. The research has been conducted in a third-year high school class. Data has been primarily collected through two surveys submitted to students. Activities have been prepared considering both scholars’ suggestions and the students’ answers to the first questionnaire. Results show that appreciation is strictly related to understanding of the plot. The viewing of a cinematographic interpretation of the play and class discussions appear to be the activities which eased understanding and thus enhanced dramatic appreciation. On the other hand, performing did not appeal to the students; in spite of the fact that most critics claim it to be an essential part of drama teaching, learners did not find this activity particularly stimulating or designed to increase dramatic appreciation. Relatore: Paolo Jacomelli. Materia: inglese.
Dimensional analysis in relativity and in differential geometry
Creators: name: Mana, P. G. L. Porta
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: This note provides a short guide to dimensional analysis in Lorentzian and general relativity and in differential geometry. It tries to revive Dorgelo and Schouten's notion of 'intrinsic' or 'absolute' dimension of a tensorial quantity. The intrinsic dimension is independent of the dimensions of the coordinates and expresses the physical and operational meaning of a tensor. The dimensional analysis of several important tensors and tensor operations is summarized. In particular it is shown that the components of a tensor need not have all the same dimension, and that the Riemann (once contravariant and thrice covariant), Ricci (twice covariant), and Einstein (twice covariant) curvature tensors are dimensionless. The relation between dimension and operational meaning for the metric and stress-energy-momentum tensors is discussed; and the possible conventions for the dimensions of these two tensors and of Einstein's constant $κ$, including the curious possibility $κ= 8πG$ without $c$ factors, are reviewed.
description: 39 pages. V7: Corrected typos and discussion of 4-velocity