cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Reconstructing pedigrees: some identifiability questions for a recombination-mutation model
Creators: name: Thatte, Bhalchandra D.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: Combinatorics (math.CO)
subject: FOS: Biological sciences
subject: FOS: Mathematics
subject: 60, 05 (Primary) 92D, 05C60 (Secondary)

description: Pedigrees are directed acyclic graphs that represent ancestral relationships between individuals in a population. Based on a schematic recombination process, we describe two simple Markov models for sequences evolving on pedigrees - Model R (recombinations without mutations) and Model RM (recombinations with mutations). For these models, we ask an identifiability question: is it possible to construct a pedigree from the joint probability distribution of extant sequences? We present partial identifiability results for general pedigrees: we show that when the crossover probabilities are sufficiently small, certain spanning subgraph sequences can be counted from the joint distribution of extant sequences. We demonstrate how pedigrees that earlier seemed difficult to distinguish are distinguished by counting their spanning subgraph sequences.
description: 40 pages, 9 figures
CITP SOP CeleST Preparation V 2.0
Creators: name: Caenorhabditis Intervention Testing Program
Publisher: name: figshare
Year: 2021
Subjects: subject: Pharmacology
subject: Physiology
subject: FOS: Biological sciences
subject: Cell Biology

description: The Caenorhabditis Intervention Testing Program (CITP) is a multi-institutional program that seeks robust and reproducible pro-longevity interventions that are efficacious across genetically diverse cohorts in the Caenorhabditis genus. The project features a unique design in which multiple experimental replicates are collected by three different laboratories at discrete locations for all candidate compounds tested. To limit confounding factors that may influence experimental reproducibility, we develop standardized operating procedures (SOPs) for all experimental procedures. Here we provide the CITP's version 2.0 SOPs for animal preparation prior to assaying health using the C. elegans Swim Test (CeleST) health assay.
Gamma Rays From The Galactic Center and the WMAP Haze
Creators: name: Hooper, Dan
name: Linden, Tim
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Recently, an analysis of data from the Fermi Gamma Ray Space Telescope has revealed a flux of gamma rays concentrated around the inner ~0.5 degrees of the Milky Way, with a spectrum that is sharply peaked at 2-4 GeV. If interpreted as the products of annihilating dark matter, this signal implies that the dark matter consists of particles with a mass between 7.3 and 9.2 GeV annihilating primarily to charged leptons. This mass range is very similar to that required to accommodate the signals reported by CoGeNT and DAMA/LIBRA. In addition to gamma rays, the dark matter is predicted to produce energetic electrons and positrons in the Inner Galaxy, which emit synchrotron photons as a result of their interaction with the galactic magnetic field. In this letter, we calculate the flux and spectrum of this synchrotron emission assuming that the gamma rays from the Galactic Center originate from dark matter, and compare the results to measurements from the WMAP satellite. We find that a sizable flux of hard synchrotron emission is predicted in this scenario, and that this can easily account for the observed intensity, spectrum, and morphology of the "WMAP Haze".
description: 5 pages, 4 figures
Dinuclear silver-bis(N-heterocyclic carbene) complexes: Synthesis, catalytic activity in propargylamine formation and computational studies
Creators: name: Atli, Deniz Demir
name: Şen, Betül
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Biophysics
subject: Biochemistry
subject: Space Science
subject: 29999 Physical Sciences not elsewhere classified
subject: FOS: Physical sciences
subject: Molecular Biology
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Sociology
subject: FOS: Sociology
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences

description: Preparation of a series of 1,1′-dialkyl-3,3′-(2-methylenepropane-1,3-diyl)dibenzimidazolium salts (alkyl = ethyl, propyl, butyl) (2a-2c) and their dinuclear bis(N-heterocyclic carbene) silver complexes (3a-3c) is reported. The silver complexes were synthesized via in situ deprotonation with Ag2O in 67-74% yields. The structural definitions of the synthesized compounds were performed by 1H NMR, 13C NMR, elemental analysis, FT-IR and also LC-MSMS techniques (only for 3a-3c). The silver complexes were utilized for three-component coupling reactions of aldehydes, amines and alkynes (A3-coupling). It was found that increasing the chain length of the alkyl substituent on the N-heterocyclic carbene ligand led to increase in catalytic performance. 3c showed the highest activity with 81% yield and with TON of 27 for N,N-diethyl-3-phenylprop-2-yn-1-amine formation. Geometry optimization was performed and geometric parameters were calculated for the compounds. The theoretical harmonic vibration frequencies of molecules were computed by DFT/B3LYP methods for their optimized geometries.
A Geometric Approach to the 3-Body and N-Body Problem in the Modified Ω-Model, with Application to the Sun–Earth–Moon System
Creators: name: Brent Jarvis
Publisher: name: Zenodo
Year: 2025
Subjects: subject: Physics
subject: Physics
subject: Physics/methods
subject: Nuclear physics
subject: Particle physics
subject: Nuclear physics
subject: Atomic physics
subject: Quantum physics
subject: Theoretical physics

description: We present a geometric formulation of the three-body and n-body problems based on the modified Ω-model, in which the effective interactions are derived from a dual-frequency curvature invariant. Using a torus geometry (with poloidal radius r = c/f2) and compactified time, we express pairwise interactions in terms of orbital (toroidal)frequency f1 and torsional (poloidal) frequency f2. Summing these pairwise forces yields an effective curvature field that governs the dynamics of multi-body systems. We then test this approach on the Sun–Earth–Moon three-body system, showing it reproduces the observed 18.7-year lunar nodal regression cycle and a deep torsionalnutation period near 2347 years. These results are in excellent agreement with observational data and illustrate the model’s ability to unify multi-body gravitationaldynamics under a single geometric framework. Keywords: Ω-model, three-body problem, n-body problem, dual-frequency curvature, lunar nodal regression, nutation, unified field theory, resonance, geometric dynamics.
Green synthesis of mesoporous MoS2 nanoflowers for efficient photocatalytic degradation of Congo red dye
Creators: name: Ullah, Haseeb
name: Khan, Zaibunisa
name: Nasir, Jamal Abdul
name: Balkan, Timuçin
name: Butler, Ian S.
name: Kaya, Sarp
name: Rehman, Zia ur
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Biophysics
subject: Microbiology
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Inorganic Chemistry
subject: Science Policy

description: A one-step, facile and scalable hydrothermal route was employed to synthesize molybdenum disulfide (MoS2) nanoflowers (NFs) for use in the photodegradation of Congo red (CR) dye. The phase purity, morphology, and structural features of the produced mesoporous MoS2-NFs were examined using PXRD, FESEM, EDX, XPS, BET, Raman and UV-visible DRS techniques. The nitrogen adsorption-desorption isotherms display a clear H3-type of hysteresis loop at P/Po of 0.8–1.0, which affords an insight into the mesoporous nature of the MoS2 NFs with a pore diameter of 1.5 to 40 nm. The mesoporous MoS2 NFs showed excellent CR degradation activity under solar light irradiation with a Kapp of 0.76 × 10−2 min−1. Importantly, the results showed a notable impact of reaction media on the degradation of CR suggesting that pH 7 is a favorable medium for this particular catalytic reaction. A kinetic study has illustrated that photodegradation of CR follows pseudo-first order kinetics. This work illustrates that mesoporous MoS2 NFs can be used as an efficient photocatalyst for the degradation of highly toxic and hazardous organic dyes in environmental remediation.
Microscopic approach to orientational order of domain walls
Creators: name: Barci, Daniel G.
name: Stariolo, Daniel A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We develop a fully microscopic, statistical mechanics approach to study phase transitions in Ising systems with competing interactions at different scales. Our aim is to consider orientational and positional order parameters in a unified framework. In this work we consider two dimensional stripe forming systems, where nematic, smectic and crystal phases are possible. We introduce a nematic order parameter in a lattice, which measures orientational order of interfaces. We develop a mean field approach which leads to a free energy which is a function of both the magnetization (density) and the orientational (nematic) order parameters. Self-consistent equations for the order parameters are obtained and the solutions are described for a particular system, the Dipolar Frustrated Ising Ferromagnet. We show that this system has an Ising-nematic phase at low temperatures in the square lattice, where positional order (staggered magnetization) is zero. At lower temperatures a crystal-stripe phase may appear. In the continuum limit the present approach connects to a Ginsburg-Landau theory, which has an isotropic-nematic phase transition with breaking of a continuous symmetry.
description: 9 pages, 7 figures, revised and expanded, published version
ELEMENTOS TUBULARES PARA CONSTRUÇÃO DE POÇOS DE PETRÓLEO
Creators: name: Porto, Tamara Barbosa
Publisher: name: figshare
Year: 2021
Subjects: subject: 91406 Petroleum and Reservoir Engineering
subject: FOS: Environmental engineering

description: Tubular goods are essential in the oil and gas industry whose applicability ranges from exploration and production activities (drilling, completion and production of wells) to transportation to refineries and distribution networks carrying oil and natural gas. The conditions under which oil and gas companies operate today become increasingly complex to find and exploit new reserves, bringing extraordinary demands to pipe manufacturers and service providers. Tubular steel goods are used in well drilling and completion activities and are manufactured in a range of tested materials with characteristics suited to meet specific needs and applications in highly challenging application scenarios. Quality and reliability are key factors in an industry where investments involve great economic, human, environmental risks. The present work aims, through a literature review, to describe how the importance of tubular elements (linings and column) for structural integrity (mechanical loading, corrosion, etc.) and hydraulic (minimizing leakage problems, specifying and correctly qualifying connections) of wells. The research was carried out through information collected in scientific articles, monographs, patents, books and master's and doctoral dissertations that were obtained in electronic databases, as well as in the OnePetro portal of the Society of Petroleum Engineers (SPE), ISO (International Organization For Standardization) and Petrobras standards available in digital media. It was possible to discuss in a general way the components of column and coatings, their functions, the efforts suffered and the difficulties encountered during the life of the well, being able this contribution to contribute with future works of academic ends.
TCC_TAMARA_PORTO_FINAL.pdf
Creators: name: Porto, Tamara Barbosa
Publisher: name: figshare
Year: 2019
Subjects: subject: 91406 Petroleum and Reservoir Engineering
subject: FOS: Environmental engineering

description: Tubular goods are essential in the oil and gas industry whose applicability ranges from exploration and production activities (drilling, completion and production of wells) to transportation to refineries and distribution networks carrying oil and natural gas. The conditions under which oil and gas companies operate today become increasingly complex to find and exploit new reserves, bringing extraordinary demands to pipe manufacturers and service providers. Tubular steel goods are used in well drilling and completion activities and are manufactured in a range of tested materials with characteristics suited to meet specific needs and applications in highly challenging application scenarios. Quality and reliability are key factors in an industry where investments involve great economic, human, environmental risks. The present work aims, through a literature review, to describe how the importance of tubular elements (linings and column) for structural integrity (mechanical loading, corrosion, etc.) and hydraulic (minimizing leakage problems, specifying and correctly qualifying connections) of wells. The research was carried out through information collected in scientific articles, monographs, patents, books and master's and doctoral dissertations that were obtained in electronic databases, as well as in the OnePetro portal of the Society of Petroleum Engineers (SPE), ISO (International Organization For Standardization) and Petrobras standards available in digital media. It was possible to discuss in a general way the components of column and coatings, their functions, the efforts suffered and the difficulties encountered during the life of the well, being able this contribution to contribute with future works of academic ends.
Embedding almost-complex manifolds in almost-complex Euclidean spaces
Creators: name: Di Scala, Antonio J.
name: Zuddas, Daniele
Publisher: name: arXiv
Year: 2010
Subjects: subject: Differential Geometry (math.DG)
subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 32Q60, 32H02

description: We show that any compact almost-complex manifold of complex dimension m can be pseudo-holomorphically embedded in R^(6m) equipped with a suitable almost-complex structure.
description: some typo corrections
D3.1 Code for ensemble evaluation in prototype
Creators: name: Brasseur P
name: Brankart J.M
name: Popov M
Publisher: name: Zenodo
Year: 2021
Subjects: SEAMLESS
CMEMS
data assimilation
code

description: One of the main objectives of SEAMLESS is to develop innovative open-source based generation and assimilation methods to accelerate the transition of the physical and biological components of CMEMS MFCs to probabilistic systems, with a better ability to provide products with faithful associated uncertainties. The purpose of this document is to introduce Deliverable D3.1, which consists of a toolbox (code) developed to assess the quality and relevance of model-generated ensembles and to provide probabilistic evaluation scores of ensemble assimilation methods. The toolbox is delivered as a code freely available at https://github.com/brankart/ensdam, supplemented by a user’s guide shown in annex of this document. The package has been conceived in order to be easily plugged into existing software (such as the SEAMLESS prototype in WP2) used by all SEAMLESS partners in the frame of the present project, or applicable to ensemble-based CMEMS assimilation systems as well as other external prediction systems (e.g. the OceanPredict community). The user’s guide was written with the objective of presenting the tools in a consistent and “demystified” way in order to facilitate their learning, while avoiding the more complex mathematical formulations and technical details that are otherwise available in the referenced publications (see end of annex).
The MeqTrees software system and its use for third-generation calibration of radio interferometers
Creators: name: Noordam, Jan E.
name: Smirnov, Oleg M.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The formulation of the radio interferometer measurement equation (RIME) by Hamaker et al. has provided us with an elegant mathematical apparatus for better understanding, simulation and calibration of existing and future instruments. The calibration of the new radio telescopes (LOFAR, SKA) would be unthinkable without the RIME formalism, and new software to exploit it. MeqTrees is designed to implement numerical models such as the RIME, and to solve for arbitrary subsets of their parameters. The technical goal of MeqTrees is to provide a tool for rapid implementation of such models, while offering performance comparable to hand-written code. We are also pursuing the wider goal of increasing the rate of evolution of radio astronomical software, by offering a tool for rapid experimentation and exchange of ideas. MeqTrees is implemented as a Python-based front-end called the meqbrowser, and an efficient (C++-based) computational back-end called the meqserver. Numerical models are defined on the front-end via a Python-based Tree Definition Language (TDL), then rapidly executed on the back-end. The use of TDL facilitates an extremely short turn-around time for experimentation with new ideas. This is also helped by unprecedented visualization capabilities for all final and intermediate results. A flexible data model and a number of important optimizations in the back-end ensures that the numerical performance is comparable to that of hand-written code. MeqTrees is already widely used as the simulation tool for new instruments (LOFAR, SKA) and technologies (focal plane arrays). It has demonstrated that it can achieve a noise-limited dynamic range in excess of a million, on WSRT data. It is the only package that is specifically designed to handle what we propose to call third-generation calibration (3GC), which is needed for the new generation of giant radio telescopes.
description: 15 pages; 14 figures
MissForest - nonparametric missing value imputation for mixed-type data
Creators: name: Stekhoven, Daniel J.
name: Bühlmann, Peter
Publisher: name: arXiv
Year: 2011
Subjects: subject: Applications (stat.AP)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Modern data acquisition based on high-throughput technology is often facing the problem of missing data. Algorithms commonly used in the analysis of such large-scale data often depend on a complete set. Missing value imputation offers a solution to this problem. However, the majority of available imputation methods are restricted to one type of variable only: continuous or categorical. For mixed-type data the different types are usually handled separately. Therefore, these methods ignore possible relations between variable types. We propose a nonparametric method which can cope with different types of variables simultaneously. We compare several state of the art methods for the imputation of missing values. We propose and evaluate an iterative imputation method (missForest) based on a random forest. By averaging over many unpruned classification or regression trees random forest intrinsically constitutes a multiple imputation scheme. Using the built-in out-of-bag error estimates of random forest we are able to estimate the imputation error without the need of a test set. Evaluation is performed on multiple data sets coming from a diverse selection of biological fields with artificially introduced missing values ranging from 10% to 30%. We show that missForest can successfully handle missing values, particularly in data sets including different types of variables. In our comparative study missForest outperforms other methods of imputation especially in data settings where complex interactions and nonlinear relations are suspected. The out-of-bag imputation error estimates of missForest prove to be adequate in all settings. Additionally, missForest exhibits attractive computational efficiency and can cope with high-dimensional data.
description: Submitted to Oxford Journal's Bioinformatics on 3rd of May 2011
Neural network protocol to predict interfacial tension for CO2/CH4/Water-Brine ternary systems under reservoir temperature and pressure ranges
Creators: name: da Silva Pereira, Andréa
name: de Oliveira, Arthur Reys Carvalho
name: Silvino, Pedro F. G.
name: Bastos-Neto, Moises
name: Lucena, Sebastião M. P.
Publisher: name: Taylor & Francis
Year: 2022
Subjects: subject: Biophysics
subject: 29999 Physical Sciences not elsewhere classified
subject: FOS: Physical sciences
subject: Medicine
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: Cancer
subject: Computational Biology

description: The increasing importance of CO2 in reservoir engineering demands more accurate models for predicting interfacial tension (IFT). We investigated the use of neural networks to predict the IFT of ternary systems CO2/CH4/Water-Brine in a wide range of reservoir conditions, since the existing correlations do not capture all of the system's mechanisms. We introduced an optimization associated with k-fold cross validation to find optimal architecture and ensure an unbiased model. The average absolute relative error obtained is 1.33% (water) and 1.99% (brine) considerably more accurate than the best empirical models tested: 9.87% (water) and 19.11% (brine). Molecular dynamics simulation performed confirms the high superficial activity of CO2.
Automatic detection of geometrical anomalies in composites manufacturing : a deep learning-based computer vision approach
Creators: name: Djavadifar, Abtin
Publisher: name: University of British Columbia
Year: 2020

description: This thesis focuses on the development of a machine learning-based vision system for quality control of composite manufacturing processes. Deep Convolutional Neural Networks (DCNNs) are used to build a real-time end-to-end solution for the complex process of draping of the fiber-reinforced cut-pieces by conducting online visual inspection. The visual inspection will ultimately help with manufacturing of double-curved composite parts such as aircraft’s rear pressure bulkhead. The developed solution provides accurate and robust measurement without the need for expensive coordinate measuring machines (CMM) in the shop floor. The development of inspection software is completed in the following two stages. In stage I, after creating a hand-labeled visual dataset acquired from a fabric layup robotic system in the German Aerospace Center (DLR), a DCNN was designed, trained and tested for image classification. Then, the idea of combining images from multiple cameras for generalization of the designed model to different wrinkle properties and environments was evaluated. The proposed method employs computer vision techniques and Dempster-Shafer Theory (DST) to enhance wrinkle detection accuracy without the need for any additional hand-labeling or re-training of the model. By the application of the DST rule of combination, the overall wrinkle detection accuracy was greatly improved. In stage II, four state-of-the-art image segmentation DCNN models (DeepLab V3+, U-Net, Mask-RCNN, IC-Net) were evaluated to accurately identify the gripper, fabric, and any probable wrinkle on a dry fiber product. The results show using a DCNN model and transfer learning can lead to acceptable results while training on a small and inaccurately annotated dataset. Also, the impact of human annotation quality on the performance of DCNN models was evaluated by comparing two human-annotated datasets. Then, an approach for detection of wrinkles at the early stages of formation was developed and evaluated. Finally, the challenges of using synthetically generated data for training the models were assessed by conducting complementary experiments. The developed solution can be practically used for visual inspection of the draping process in composite manufacturing facilities. The presented method can be readily adopted to train DCNN models using other datasets and perform visual inspection tasks in different automated manufacturing processes.
Precise RVs and Stellar Magnetic Field Measurements via LSD
Creators: name: Lienhard, Florian
Publisher: name: Zenodo
Year: 2021
Subjects: techniques: radial velocities
line: profiles
planets and satellites: detection
stars: magnetic field

description: To improve the accuracy of planetary mass estimates and ultimately detect Earth twins, it is crucial to find more reliable radial velocity extraction methods.
 The Least-Squares Deconvolution (LSD) technique has been used to infer the stellar magnetic flux from spectropolarimetric data for the past two decades. It relies on the assumption that stellar absorption lines are similar in shape and only scale up by a wavelength-specific factor. Although this assumption is simplistic, LSD provides a good model for intensity spectra and likewise an estimate for their Doppler shift.
 We present a radial velocity extraction pipeline combining LSD with state-of-the-art preprocessing techniques. The flexibility of LSD allows to select or exclude spectral lines or pixels at will, providing a means to exclude variable lines or pixels affected by instrumental problems. The LSD pipeline was tested on HARPS-N data for which it delivered RV time series with on average 10 per cent lower scatter as compared to the HARPS-N RV extraction pipeline based on the Cross-Correlation Function technique. The full description of this pipeline will be provided in an upcoming paper: Lienhard et al. (soon to be submitted).
A digital interface for Gaussian relay and interference networks: Lifting codes from the discrete superposition model
Creators: name: Anand, M.
name: Kumar, P. R.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: For every Gaussian network, there exists a corresponding deterministic network called the discrete superposition network. We show that this discrete superposition network provides a near-optimal digital interface for operating a class consisting of many Gaussian networks in the sense that any code for the discrete superposition network can be naturally lifted to a corresponding code for the Gaussian network, while achieving a rate that is no more than a constant number of bits lesser than the rate it achieves for the discrete superposition network. This constant depends only on the number of nodes in the network and not on the channel gains or SNR. Moreover the capacities of the two networks are within a constant of each other, again independent of channel gains and SNR. We show that the class of Gaussian networks for which this interface property holds includes relay networks with a single source-destination pair, interference networks, multicast networks, and the counterparts of these networks with multiple transmit and receive antennas. The code for the Gaussian relay network can be obtained from any code for the discrete superposition network simply by pruning it. This lifting scheme establishes that the superposition model can indeed potentially serve as a strong surrogate for designing codes for Gaussian relay networks. We present similar results for the K x K Gaussian interference network, MIMO Gaussian interference networks, MIMO Gaussian relay networks, and multicast networks, with the constant gap depending additionally on the number of antennas in case of MIMO networks.
description: Final version
Efficient use of oil in water macroemulsions as enhanced oil recovery agents
Creators: name: Hernandez-Perez, Joaquin
name: Likhanova, Natalya
name: Lopez-Falcon, Dennys
name: Olivares-Xometl, Octavio
name: Munoz-Salazar, Laura
name: Trejo-Zarraga, Fernando
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Biophysics
subject: Biochemistry
subject: Space Science
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Developmental Biology

description: To obtain some insights into the transport of macroemulsions prepared outside of the reservoir for oil recovery through porous media, laboratory experiments were run by injecting different formulations of diluted oil in water emulsions through sandstone cores. Emulsions, whose disperse phase was 70%, were stable for one year. Mathematical model parameters were fitted with data from emulsion transport experiments. According to this model, it is enough to inject 0.1 pore volume of emulsion slug for its adequate transportation through porous media. Oil displacement tests were carried out as part of a secondary recovery process, followed by the injection of an emulsion slug, and then again by water flooding to obtain additional oil recovery up to 23.5%. At the same concentration, emulsions based on a hydrophobic compound were more effective than emulsions prepared from crude oil, obtaining a difference of cumulative residual oil recovery of around 12%. The injection of an emulsion slug at 1 wt.% of concentration and 0.1 pore volume after waterflooding is both a promising alternative and technically viable additional recovery method. Emulsions were stable for a long time and easyly diluted with water, which can be very useful in mature oilfields.
Metamagnetism and soliton excitations in the modulated ferromagnetic Ising chain CoV2O6
Creators: name: Kimber, Simon A. J.
name: Mutka, Hannu
name: Chatterji, Tapan
name: Hoffman, Tommy
name: Henry, Paul F.
name: Bordallo, Heloisa N.
name: Argyriou, Dimitri N.
name: Attfield, J. Paul.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We report a combination of physical property and neutron scattering measurements for polycrystalline samples of the one-dimensional spin chain compound CoV2O6. Heat capacity measurements show that an effective S = 1/2 state is found at low temperatures and that magnetic fluctuations persist up to 6.Tn. Above Tn = 6.3 K, measurements of the magnetic susceptibility as a function of T and H show that the nearest neighbour exchange is ferromagnetic. In the ordered state, we have discovered a crossover from a metamagnet with strong fluctuations between 5 K and Tn to a state with a 1/3 magnetisation plateau at 2 < T < 5 K. We use neutron powder diffraction measurements to show that the AFM state has incommensurate long range order and inelastic time of flight neutron scattering to examine the magnetic fluctuations as a function of temperature. Above Tn, we find two broad bands between 3.5 and 5 meV and thermally activated low energy features which correspond to transitions within these bands. These features show that the excitations are deconfined solitons rather than the static spin reversals predicted for a uniform FM Ising spin chain. Below Tn, we find a ladder of states due to the confining effect of the internal field. A region of weak confinement below Tn, but above 5 K, is identified which may correspond to a crossover between 2D and 3D magnetic ordering.
description: Expanded version, includes results from arXiv:0804.2966 and neutron powder diffraction. To appear in PRB
title: Satzung zur Änderung der Ordnung zur Änderung und Neufassung der Satzung der Studierendenschaft der Universität Paderborn
title: vom 11. September 2017
titleType: Subtitle
Creators: name: Universität Paderborn
Publisher: name: UB-PAD - Paderborn University Library
Year: 2017

description: Amtliche Mitteilungen / Universität Paderborn
Single crystal growth of BaFe$_{2-x}$Co$_x$As$_2$ without fluxing agent
Creators: name: Zhang, Changjin
name: Zhang, Lei
name: Xi, Chuanying
name: Ling, Langsheng
name: Tan, Shun
name: Zhang, Yuheng
Publisher: name: arXiv
Year: 2010
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We report a simple, reliable method to grow high quality BaFe$_{2-x}$Co$_x$As$_2$ single crystal samples without using any fluxing agent. The starting materials for the single crystal growth come from well-crystallized polycrystalline samples and the highest growing temperature can be 1493 K. The as-grown crystals have typical dimensions of 4$\times3\times$0.5 mm$^3$ with c-axis perpendicular to the shining surface. We find that the samples have very large current carrying ability, indicating that the samples have good potential technological applications.
description: 8 pages, 4 figures, accepted by Journal of Superconductivity and Novel Magnetism
title: Das sowjetische Modell - Über Fiktionen zu den Realitäten
Creators: name: Beyrau, Dietrich
name: Zentrum Für Zeithistorische Forschung
Publisher: name: ZZF - Centre for Contemporary History
Year: 2017

description: Arbeiter im Staatssozialismus. Ideologischer Anspruch und soziale Wirklichkeit
Mapping and Understanding Patterns of Air Quality Using Satellite Data and Machine Learning
Creators: name: Stirnberg, Roland
name: Cermak, Jan
name: Fuchs, Julia
name: Andersen, Hendrik
Publisher: name: FID GEO
Year: 2020

description: The quantification of factors leading to harmfully high levels of particulate matter (PM) remains challenging. This study presents a novel approach using a statistical model that is trained to predict hourly concentrations of particles smaller than 10 μm (PM10) by combining satellite-borne aerosol optical depth (AOD) with meteorological and land-use parameters. The model is shown to accurately predict PM10 (overall R 2 = 0.77, RMSE = 7.44 μg/m 3) for measurement sites in Germany. The capability of satellite observations to map and monitor surface air pollution is assessed by investigating the relationship between AOD and PM10 in the same modeling setup. Sensitivity analyses show that important drivers of modeled PM10 include multiday mean wind flow, boundary layer height (BLH), day of year (DOY), and temperature. Different mechanisms associated with elevated PM10 concentrations are identified in winter and summer. In winter, mean predictions of PM10 concentrations >35 μg/m 3 occur when BLH is below ∼500 m. Paired with multiday easterly wind flow, mean model predictions surpass 40 μg/m 3 of PM10. In summer, PM10 concentrations seemingly are less driven by meteorology, but by emission or chemical particle formation processes, which are not included in the model. The relationship between AOD and predicted PM10 concentrations depends to a large extent on ambient meteorological conditions. Results suggest that AOD can be used to assess air quality at ground level in a machine learning approach linking it with meteorological conditions.
Single-Spin Addressing in an Atomic Mott Insulator
Creators: name: Weitenberg, Christof
name: Endres, Manuel
name: Sherson, Jacob F.
name: Cheneau, Marc
name: Schauß, Peter
name: Fukuhara, Takeshi
name: Bloch, Immanuel
name: Kuhr, Stefan
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Ultracold atoms in optical lattices are a versatile tool to investigate fundamental properties of quantum many body systems. In particular, the high degree of control of experimental parameters has allowed the study of many interesting phenomena such as quantum phase transitions and quantum spin dynamics. Here we demonstrate how such control can be extended down to the most fundamental level of a single spin at a specific site of an optical lattice. Using a tightly focussed laser beam together with a microwave field, we were able to flip the spin of individual atoms in a Mott insulator with sub-diffraction-limited resolution, well below the lattice spacing. The Mott insulator provided us with a large two-dimensional array of perfectly arranged atoms, in which we created arbitrary spin patterns by sequentially addressing selected lattice sites after freezing out the atom distribution. We directly monitored the tunnelling quantum dynamics of single atoms in the lattice prepared along a single line and observed that our addressing scheme leaves the atoms in the motional ground state. Our results open the path to a wide range of novel applications from quantum dynamics of spin impurities, entropy transport, implementation of novel cooling schemes, and engineering of quantum many-body phases to quantum information processing.
description: 8 pages, 5 figures
title: Sozialgeschichte der Arbeiterschaft und staatssozialistische Entwicklungspfade: konzeptionelle Überlegungen und eine Erklärungsskizze
Creators: name: Boyer, Christoph
name: Zentrum Für Zeithistorische Forschung
Publisher: name: ZZF - Centre for Contemporary History
Year: 2017

description: Arbeiter im Staatssozialismus. Ideologischer Anspruch und soziale Wirklichkeit
title: Die Arbeiter als Modernisierungsbremse im realsozialistischen Bulgarien?
Creators: name: Georgiev, Ivo
name: Zentrum Für Zeithistorische Forschung
Publisher: name: ZZF - Centre for Contemporary History
Year: 2017

description: Arbeiter im Staatssozialismus. Ideologischer Anspruch und soziale Wirklichkeit
Controlled Cellular Delivery of Amphiphilic Cargo by Redox-Responsive Nanocontainers
Creators: name: De Vries, Wilke C.
name: Kudruk, Sergej
name: Grill, David
name: Niehues, Maximilian
name: Matos, Anna Livia Linard
name: Wissing, Maren
name: Studer, Armido
name: Gerke, Volker
name: Ravoo, Bart Jan
Publisher: name: FID GEO
Year: 2019

description: Abstract The specific transport of amphiphilic compounds such as fluorescently labeled phospholipids into cells is a prerequisite for the analysis of highly dynamic cellular processes involving these molecules, e.g., the intracellular distribution and metabolism of phospholipids. However, cellular delivery remains a challenge as it should not affect the physiological integrity and morphology of the cell membrane. To address this, polymer nanocontainers based on redox-responsive cyclodextrin (CD) amphiphiles are prepared, and their potential to deliver fluorescently labeled phospholipids to intracellular membrane compartments is analyzed. It is shown that mixtures of reductively degradable cyclodextrin amphiphiles and different phospholipids form liposome-like vesicles (CD–lipid vesicles, CSSLV) with a homogeneous distribution of each lipid. Host–guest-mediated self-assembly of a cystamine-crosslinked polymer shell on these CSSLV produces polymer-shelled liposomal vesicles (PSSCSSLV) with the unique feature of a redox-sensitive CSSLV core and reductively degradable polymer shell. PSSCSSLV show high stability and a redox-sensitive release of the amphiphilic cargo. Live cell experiments reveal that the novel PSSCSSLV are readily internalized by primary human endothelial cells and that the reductive microenvironment of the cells' endosomes triggers the release of the amphiphilic cargo into the cytosol. Thus, PSSCSSLV represent a highly efficient system to transport lipid-like amphiphilic cargo into the intracellular environment.
title: Dramaturgie der Utopie. Kulturgeschichte der Rituale der Arbeiter-und-Bauern-Macht
Creators: name: Gries, Rainer
name: Zentrum Für Zeithistorische Forschung
Publisher: name: ZZF - Centre for Contemporary History
Year: 2017

description: Arbeiter im Staatssozialismus. Ideologischer Anspruch und soziale Wirklichkeit
Some considerations on the present-day results for the detection of frame-dragging after the final outcome of GP-B
Creators: name: Iorio, Lorenzo
Publisher: name: arXiv
Year: 2011
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: The cancelation of the first even zonal harmonic coefficient J2 of the multipolar expansion of the Newtonian part of the Earth's gravitational potential from the linear combination f(2L) of the nodes of LAGEOS and LAGEOS II used in the latest tests of the general relativistic Lense-Thirring effect cannot be perfect, as assumed so far. It is so, among other things, because of the uncertainties in the spatial orientation of the terrestrial spin axis as well. As a consequence, the coefficient c1 entering f(2L), which is not a solve-for parameter being theoretically computed from the analytical expressions of the classical node precessions due to J2, is, on average, uncertain at a 10-8 level over multi-decadal time spans DT comparable to those used in the data analyses performed so far. A further \simeq 20% systematic uncertainty in the theoretically predicted gravitomagnetic signal, thus, occurs. The shift due to the gravitomagnetic frame-dragging on the station-spacecraft range is numerically computed over DT = 15 d and DT = 1 yr. The need of looking at such a directly observable quantity is pointed out, along with some critical remarks concerning the methodology used so far to measure the Lense-Thirring effect with the LAGEOS satellites. Suggestions for a different, more trustable and reliable approach are offered.
description: LaTex2e, 6 pages, 1 table, 5 figures, 36 references. Minor changes. Version matching the one at press in Europhysics Letters (EPL)
Plio-Pleistocene Variability of the East Pacific Thermocline and Atmospheric Systems
Creators: name: Ronge, T. A.
name: Nürnberg, D.
name: Tiedemann, R.
Publisher: name: FID GEO
Year: 2020

description: The transition from the Pliocene to the Pleistocene was accompanied by major tectonic reorganizations of key oceanic gateways. In particular, the gradual closure of the Panama Gateway and the constriction of the Indonesian Gateway significantly affected the structure of the Pacific thermocline. In the East Pacific, the thermocline shoaled from an early Pliocene El Niño-like depth to its modern state, which had significant implications for global climate. Here we use Mg/Ca temperature estimates from subsurface and thermocline dwelling foraminifera to reconstruct the meridional Plio-Pleistocene evolution of the Southeast Pacific thermocline, in relation to atmospheric circulation changes. In combination with similar reconstructions from the north-equatorial Pacific, our data indicate a change in the thermocline, responding to the northward displacement of the Intertropical Convergence Zone/South Pacific High system between ~3.8 and 3.5 Ma. After 3.5 Ma, we record a second major phase of thermocline shoaling, which points to the Intertropical Convergence Zone/South Pacific High-system movement toward its modern position along with the gradual cooling of the Northern Hemisphere and its associated glaciation. These findings highlight that a warming globe may affect equatorial regions more intensively due to the potential temperature-driven movement of the Intertropical Convergence Zone/South Pacific High and their associated oceanic systems.
Ecological literacy, environmental ethics and contextual conceptions of education : the case of Shia people of Fashapooyeh village, Tehran county, Iran.
Creators: name: Eskandari, Mahtab
Publisher: name: University of British Columbia
Year: 2020

description: The main questions addressed in this study are in the domains of ecological literacy, environmental ethics and contextual conceptions of education. Hence the study uses the case of Shia people of Iran and their environmental ethics to investigate the trans-historical realities in conceptualizing science-humanism in association with dominant notions of nature, the environment and ecology. In particular, special focus is directed at understandings and practices associated with environmental education in the context of local Shia people in Fashapooyeh, a traditional village in the county of Tehran in Iran. Major cultural ways of education existing in this context were explored, and their relation to contextual ontologies were examined. Thus, methodologically, the study employed articulation of dis-orientalising strategies in order to avoid oriental dogmas with respect to the particular context of the study. In this way, interpretive analytic case study methods, which drew heavily on critical ethnographic methods of field observations and interviews, were used in data collection. Revelations from the analysis of the data corpus include 1) among Shia people, actions towards/about/for/with nature are governed by ethics of religion, and they are governed by the Shia conception of humanism; 2) Everyday life schedules are interestingly governed by key calendar markers where contemporary discourses are a function of interaction between Indigeneity and modernity; 3) The Shia understanding of life is in close relation with understanding the order of nature, and that Shia identity and environmental health practices are not mutually exclusive. The findings challenge the current dominant concept of ecological literacy and its foundational preoccupation of nature, the environment, cosmos citizenship, balance and specifically the notion of literacy. These findings or revelations suggest new perspectives on conceptualizing ecological literacy in relation to ontological approaches to contemporary cultures. The outcomes challenge current dominant approaches to the concept of sustainability, and offer insight into how we might re-conceptualize and teach sustainability as a way of life grounded in their relative contextual ontologies. In the realm of Indigenous studies, the findings suggest processes of theorizing and analyzing research in respect to their particular contextual ethics and ontologies.