cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Precision big bang nucleosynthesis with improved Helium-4 predictions
Creators: name: Pitrou, Cyril
name: Coc, Alain
name: Uzan, Jean-Philippe
name: Vangioni, Elisabeth
Publisher: name: arXiv
Year: 2018
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Primordial nucleosynthesis is one of the three historical evidences for the big bang model, together with the expansion of the universe and the cosmic microwave background. Now that the number of neutrino families and the baryonic densities have been fixed by laboratory measurements or CMB observations, the model has no free parameter and its predictions are rigid. Departure from its predictions could provide hints or constraints on new physics or astrophysics in the early universe. Precision on primordial abundances deduced from observations have recently been drastically improved and reach the percent level for both deuterium and helium-4. Accordingly, the BBN predictions should reach the same level of precision. For most isotopes, the dominant sources of uncertainty come from those on the laboratory thermonuclear reactions. This article focuses on helium-4 whose predicted primordial abundance depends essentially on weak interactions which control the neutron-proton ratio. The rates of the various weak interaction processes depend on the experimentally measured neutron lifetime, but also includes numerous corrections that we thoroughly investigate here. They are the radiative, zero-temperature, corrections, finite nucleon mass corrections, finite temperature radiative corrections, weak-magnetism, and QED plasma effects, which are for the first time all included and calculated in a self consistent way, allowing to take into account the correlations between them, and verifying that all satisfy detailed balance. The helium-4 predicted mass fraction is $0.24709\pm0.00017$. In addition, we provide a Mathematica code (PRIMAT) that incorporates, not only these corrections but also a full network of reactions, using the best available thermonuclear reaction rates, allowing the predictions of primordial abundances up to the CNO region.
description: 56 pages, 31 figures
Symmetry breaking in nonuniform noncommutative $λϕ^4$ theory at finite temperature
Creators: name: Hernández, J. M.
name: Ramírez, C.
name: Sánchez, M.
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider the 2PI Cornwall-Jackiw-Tomboulis effective action at finite temperature for a noncommutative real scalar field theory in 4 dimensions, with noncommutativity among space and time variables. By means of a Rayleig-Ritz variation, we study the solutions of a stripe type nonuniform background, which depends on space and time, and hence on temperature. The analysis in the first approximation shows that such solutions appear in the planar limit, as already known, but also under normal noncommutativity, in an anisotropic region which has not been considered. Further we show that the transition from the uniform ordered phase to the non uniform one is first order.
description: 8 pages
Exiled Journalists need Support, not Autocrat-filed Skepticism
Creators: name: Cooley, Alexander A.
name: Margolin, Tatyana
Publisher: name: Columbia University
Year: 2021
Subjects: Journalists
Exiles
Authoritarianism
Freedom of the press
Civil society

description: Today's authoritarians force journalists into exile and then stigmatize them as hopelessly out of touch with local developments. To better support exiled journalists, Western civil society and media partners will have to discard outdated notions about what makes a journalist relevant.
Increasing Diversity, Equity and Inclusion (DEI) through data archiving across the UK Data Service
Creators: name: Hakins, Gemma
name: Webb, Joanne
Publisher: name: Zenodo
Year: 2023
Subjects: Racial equality
DEI
Diversity
Inclusion
UK
Research
Data
Ethnicity

description: The delivery of a fair and supportive working environment for staff is an important part of the UK Data Service. We recognise the value that diversity, equality and inclusion brings and want to recruit, develop, retain and motivate an increasingly diverse workforce.

 This poster looks at how the UK Data Service and University of Essex have strategically increased diversity across their respective organisations, in line with the continuum created by Professor Gurnam Singh in the aftermath of the George Floyd murder, July 2020. It also examples some of the key work that is happening to drive inclusivity and accessibility: from staff recruitment and cultural changes, through to data curation, research access, user testing, training, communications and impact.
description: Presented at IASSIST 2023: Diversity in research: Social Justice from data.
Semiclassical trace formula for the two-dimensional radial power-law potentials
Creators: name: Magner, A. G.
name: Vlasenko, A. A.
name: Arita, K.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: The trace formula for the density of single-particle levels in the two-dimensional radial power-law potentials, which nicely approximate the radial dependence of the Woods-Saxon potential and quantum spectra in a bound region, was derived by the improved stationary phase method. The specific analytical results are obtained for the powers 4 and 6. The enhancement phenomena near the bifurcations of periodic orbits are found to be significant for the description of the fine shell structure. It is shown that the semiclassical trace formulas for the shell corrections to the level density and energy reproduce the quantum results with good accuracy through all the bifurcation (symmetry breaking) catastrophe points, where the standard stationary-phase method breaks down. Various limits (including the harmonic oscillator and the spherical billiard) are obtained from the same analytical trace formula.
description: 19 pages, 10 figures
A mathematical justification of the Isobe-Kakinuma model for water waves with and without bottom topography
Creators: name: Iguchi, Tatsuo
Publisher: name: arXiv
Year: 2018
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We consider the Isobe-Kakinuma model for water waves in both cases of the flat and the variable bottoms. The Isobe-Kakinuma model is a system of Euler-Lagrange equations for an approximate Lagrangian which is derived from Luke's Lagrangian for water waves by approximating the velocity potential in the Lagrangian appropriately. The Isobe-Kakinuma model consists of $(N+1)$ second order and a first order partial differential equations, where $N$ is a nonnegative integer. We justify rigorously the Isobe-Kakinuma model as a higher order shallow water approximation in the strongly nonlinear regime by giving an error estimate between the solutions of the Isobe-Kakinuma model and of the full water wave problem in terms of the small nondimensional parameter $δ$, which is the ratio of the mean depth to the typical wavelength. It turns out that the error is of order $O(δ^{4N+2})$ in the case of the flat bottom and of order $O(δ^{4[N/2]+2})$ in the case of variable bottoms.
Land Cover Dynamics on the Lower Ganges–Brahmaputra Delta: Agriculture–Aquaculture Transitions, 1972–2017
Creators: name: Sousa, Daniel John
name: Small, Christopher
Publisher: name: Columbia University
Year: 2021
Subjects: Land cover
Aquaculture
Remote sensing

description: Aquaculture in tropical and subtropical developing countries has expanded in recent years. This practice is controversial due to its potential for serious economic, food security, and environmental impacts—especially for intensive operations in and near mangrove ecosystems, where many shrimp species spawn. While considerable effort has been directed toward understanding aquaculture impacts, maps of spatial extent and multi-decade spatiotemporal dynamics remain sparse. This is in part because aquaculture ponds (ghers) can be challenging to distinguish from other shallow water targets on the basis of water-leaving radiance alone. Here, we focus on the Lower Ganges–Brahmaputra Delta (GBD), one of the most expansive areas of recent aquaculture growth on Earth and adjacent to the Sundarbans mangrove forest, a biodiversity hotspot. We use a combination of MODIS 16-day EVI composites and 45 years (1972–2017) of Landsat observations to characterize dominant spatiotemporal patterns in the vegetation phenology of the area, identify consistent seasonal optical differences between flooded ghers and other land uses, and quantify the multi-decade expansion of standing water bodies. Considerable non-uniqueness exists in the spectral signature of ghers on the GBD, propagating into uncertainty in estimates of spatial extent. We implement three progressive decision boundaries to explicitly quantify this uncertainty and provide liberal, moderate, and conservative estimates of flooded gher extent on three different spatial scales. Using multiple extents and multiple thresholds, we quantify the size distribution of contiguous regions of flooded gher extent at ten-year intervals. The moderate threshold shows standing water area within Bangladeshi polders to have expanded from less than 300 km2 in 1990 to over 1400 km2 in 2015. At all three scales investigated, the size distribution of standing water bodies is increasingly dominated by larger, more interconnected networks of flooded areas associated with aquaculture. Much of this expansion has occurred in immediate proximity to the Bangladeshi Sundarbans.
The geology of the Houser Canyon pegmatite with an x-ray analysis of monazite
Creators: name: Foote, Royal S.
Publisher: name: California Institute of Technology
Year: 1951
Subjects: subject: pegmatite
subject: monazite
subject: Houser Canyon
subject: Geology
subject: FOS: Earth and related environmental sciences
subject: biotite

description: A large granitic pegmatite near Campo, in southern
San Diego County was found to contain several radioactive
biotite-rich inclusions. The pegmatite is irregularly zoned, and in general comprises a well defined graphic granite border zone, an irregular wall zone of intergrown quartz and perthite, a discontinuous intermediate zone of blocky perthite, and a well developed but somewhat irregular quartz core. The included masses of biotite-rich rock are spatially related to segments of the quartz core and their content of rare-earth minerals may be due in part to this relationship.

The inclusions are composed of interlayered biotite books and feldspar plates which form a series of folded and
distorted layers that are randomly oriented throughout the
inclusion. Separation and analysis of minerals from the
inclusion were accomplished by means of cloud-chamber detection, x-ray powder diffraction analyses, and spectrographic analysis. Thorium-bearing monazite was identified as the source of the radio-activity.

The rare-earth elements and thorium evidently were
concentrated in the late residual fluids of the pegmatite.
Pendants or inclusions of apatite-bearing schist are believed to have provided a source of phosphorous for the crystallization of monazite. As an additional result of reaction with the pegmatite solutions, the minerals of the schistose pendant were recrystallized and some mineralogic changes were made as well.
Physics performance studies for the ALICE inner tracker upgrade
Creators: name: Stiller, Johannes
Publisher: name: arXiv
Year: 2012
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: During the second long shutdown of the LHC in 2018, the ALICE Collaboration plans to install an upgrade of the ALICE Inner Tracking System (ITS) in the central barrel with seven layers of silicon detectors starting at 2.2 cm radial distance from the interaction region and a material budget as low as 0.3% radiation length per layer. A single-hit resolution of $\mathrm{4 μm}$ and a readout rate capability of up to 50 kHz in Pb--Pb collisions will allow new and unique measurements in the heavy-quark sector, i.e. charm and beauty. Using detailed Monte Carlo simulations of pp and Pb--Pb collisions we study the performance for heavy-flavor detection with an upgraded ITS in the following benchmark analyses: Charm meson and baryon production, i.e. $\mathrm{D^{0} \rightarrow K^{-}π^{+}}$ and $\mathrm{Λ_{c}^{+} \rightarrow pK^{-}π^{+}}$, and beauty meson and baryon production, i.e. displaced vertices of $\mathrm{B^{+} \rightarrow \bar{D}^{0}π^{+}}$ and $\mathrm{Λ_{b} \rightarrow Λ_{c}^{+}π^{-}}$.
description: 4 pages, 4 Figures, proceedings of Hot Quarks 2012
Analogue Special and General Relativity by Optical Multilayer Thin Films: The Rindler Space Case
Creators: name: Dehdashti, Sh.
name: Roknizadeh, R.
name: Mahdifar, A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: In this paper, to obtain an analogy between the curved spaces and the linear optics, we expand the idea of Ref.[1, 2] to the multilayer films. We investigate efects of thickness and index of refraction of the films on the Lorentzian transformations. In addition, by using the multilayer films, we suggest very simple experimental set-up which can serve as an analogue computer for testing special relativity. Finally, we draw an analogy between the Rindler space, as an example of the curved spaces, and a suitable multilayer film.
description: 5 Figures
Evolution of Urban Spatial Clusters in China: A Graph-Based Method Using Nighttime Light Data
Creators: name: Wang, Congxiao
name: Yu, Bailang
name: Chen, Zuoqi
name: Liu, Yan
name: Song, Wei
name: Li, Xia
name: Yang, Chengshu
name: Small, Christopher
name: Shu, Song
name: Wu, Jianping
Publisher: name: Columbia University
Year: 2021
Subjects: Cities and towns--Growth
Urbanization
City planning
Spanning trees (Graph theory)
Geographic information systems

description: An urban spatial cluster (USC) describes one or more geographic agglomerations and the linkages among cities. USCs are conventionally delineated based on predefined administrative boundaries of cities, without considering the dynamic and evolving nature of the spatial extent of USCs. This study uses Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime light (NTL) satellite images to quantitatively detect and characterize the evolution of USCs. We propose a dynamic minimum spanning tree (DMST) and a subgraph partitioning method to identify the evolving USCs over time, which considers both the spatial proximity of urban built-up areas and their affiliations with USCs at the previous snapshot. China is selected as a case study for its rapid urbanization process and the cluster-based economic development strategy. Four DMSTs are generated for China using the urban built-up areas extracted from DMSP/OLS NTL satellite images collected in 2000, 2004, 2008, and 2012. Each DMST is partitioned into various subtrees and the urban built-up areas connected by the same subtree are identified as a potential USC. By inspecting the evolution of USCs over time, three different types of USCs are obtained, including newly emerging, single-core, and multicore clusters. Using the rank-size distribution, we find that large-sized USCs have greater development than medium- and small-sized USCs. A clear directionality and heterogeneity are observed in the expansions of the ten largest USCs. Our study provides further insight for the understanding of urban system and its spatial structures, and assists policymakers in their planning practices at national and regional scales.
Impact pressure and total temperature interpretation at hypersonic mach number
Creators: name: Graves, J. C.
Publisher: name: California Institute of Technology
Year: 1954
Subjects: Engineering and Applied Science

description: Results are presented of an experimental investigation of impact-pressure and total-temperature interpretation at a nominal Mach number of 5.6. The data indicate that the Rayleigh equation, which assumes non-viscous flow, requires correction at low free-stream Reynolds numbers. These viscous effects are detected at Reynolds numbers (based on impact-probe diameter) as high as 6000, and they continue to increase with decreasing Reynolds numbers. At the low pressure limit of the facilities used in this investigation, the maximum viscous correction is 2.5 percent for a Reynolds number of 425.

The calibration curves for the recovery factor of a total-temperature probe are given, plus an analysis of suitable parameters with which to present this information. For the limited range of total temperatures of 200[degrees]F to 260[degrees]F, and a nominal Mach number of 5.6, single calibration curves are shown using either the free-stream Reynolds number, or the Nusselt number of the flow inside the probe (based on thermocouple wire diameter) as parameters.
title: Evapotranspiration and Energy Balance of Irrigated Urban Turfgrass
Creators: name: Miksch, Matthew D.
Publisher: name: Utah State University
Year: 2023

description: Water usage for irrigation is a big consumer of water resources in urban areas in Utah and other parts of the Intermountain Region of the Western United States. As populations continue to increase in these states, it is important to understand how much water is being used by urban landscapes in order to plan and manage future water resources. Evapotranspiration (ET), or the amount of water leaving a surface over a certain timeframe due to both transpiration from plants and evaporation from the soil, is a key variable in understanding how much water urban landscapes are really using to grow and survive. There are ways to estimate it using nearby weather station data, but this method has shown to not always be accurate for one of the more prominent urban landscapes: turfgrass. There are more rigorous ways of measuring ET, but they are much more expensive and require maintenance and processing time. Satellite remote sensing models are becoming an increasingly popular way to estimate ET as well, but they are difficult to employ in urban areas due to the dense spacing of different landscapes and man-made structures.
In this thesis, measurements of high-frequency three-dimensional wind, temperature, and humidity are collected and processed to calculate how much water was used at a golf course in a suburban area. This data is then used to validate a simple yet tested and published remote sensing model. ET measurements during the 2017 and 2018 growing season showed that in general more water was being used by the turfgrass than the recommended amount, although this changed throughout the growing season and the turfgrass was actually using less than the recommended amount during the fall months. The validation of the remote sensing model did provide a fair estimate of the average measured values, but the performance of the model was not as good as those found in other studies, likely due to properties of urban landscapes violating some of the assumptions in the model. Combining the model and its validation provide important information on how much water urban landscapes consume, along with steps forward in modeling this water use from a remote sensing perspective.
The low lying modes of triplet-condensed neutron matter and their effective theory
Creators: name: Bedaque, Paulo F.
name: Nicholson, Amy N.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The condensation of neutrons into a 3P2 superfluid phase occurs at densities relevant for the interior of neutron stars. The triplet pairing breaks rotational symmetry spontaneously and leads to the existence of gapless modes (angulons) that are relevant for many transport coefficients and to the star's cooling properties. We derive the leading terms of the low energy effective field theory, including the leading coupling to electroweak currents, valid for a variety of possible 3P2 phases.
description: Extended discussions, minor changes. Published version
Introducing shrinkage in heavy-tailed state space models to predict equity excess returns
Creators: name: Huber, Florian
name: Kastner, Gregor
name: Pfarrhofer, Michael
Publisher: name: arXiv
Year: 2018
Subjects: subject: Econometrics (econ.EM)
subject: Statistical Finance (q-fin.ST)
subject: Applications (stat.AP)
subject: FOS: Economics and business
subject: FOS: Computer and information sciences

description: We forecast S&P 500 excess returns using a flexible Bayesian econometric state space model with non-Gaussian features at several levels. More precisely, we control for overparameterization via novel global-local shrinkage priors on the state innovation variances as well as the time-invariant part of the state space model. The shrinkage priors are complemented by heavy tailed state innovations that cater for potential large breaks in the latent states. Moreover, we allow for leptokurtic stochastic volatility in the observation equation. The empirical findings indicate that several variants of the proposed approach outperform typical competitors frequently used in the literature, both in terms of point and density forecasts.
Scalable peer-to-peer streaming for live entertainment content
Creators: name: Mykoniati, Eleni
name: Landa, Raul
name: Spirou, Spiros
name: Clegg, Richard G.
name: Latif, Lawrence
name: Griffin, David
name: Rio, Miguel
Publisher: name: arXiv
Year: 2013
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: We present a system for streaming live entertainment content over the Internet originating from a single source to a scalable number of consumers without resorting to centralised or provider- provisioned resources. The system creates a peer-to-peer overlay network, which attempts to optimise use of existing capacity to ensure quality of service, delivering low start-up delay and lag in playout of the live content. There are three main aspects of our solution. Firstly, a swarming mechanism that constructs an overlay topology for minimising propagation delays from the source to end consumers. Secondly, a distributed overlay anycast system that uses a location-based search algorithm for peers to quickly find the closest peers in a given stream. Finally, a novel incentives mechanism that encourages peers to donate capacity even when the user is not actively consuming content.
description: 11 pages, 6 figures
Research on Korea Social Science Data Archive's Long-Term Development Plan
Creators: name: Yang, Jungwon
Publisher: name: Zenodo
Year: 2023
Subjects: KOSSDA, Data Preservation, Data Sharing

description: Since the 1980s, The Korean Social Science Data Archive (KOSSDA) has been the leading research data management organization for Korea’s social science data collection. In 2015, the KOSSDA became a part of the Seoul National University (SNU) research community and found a home within the Asia Center. In 2022 SNU decided to make KOSSDA an independent research organization of the College of Social Science.

 KOSSDA decided to analyze and evaluate the current KOSSDA service models to prepare for newly expanded research and service opportunities. A small group of researchers conducted usability analyses on KOSSDA data collection, the KOSSDA data education program, the KOSSDA website, and data donors. In this presentation, presenters will share the findings of these usability analyses and discuss the distinctiveness of Korea’s research data management services and data sharing patterns.
Origin and Transport Signatures of Spin-Orbit Interactions in One- and Two-Dimensional SrTiO$_3$-Based Heterostructures
Creators: name: Kim, Younghyun
name: Lutchyn, Roman M.
name: Nayak, Chetan
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study origin of Rashba spin-orbit interaction at SrTiO$_3$ surfaces and LaAlO$_3$/SrTiO$_3$ interfaces by considering the interplay between atomic spin-orbit coupling and inversion asymmetry at the surface or interface. We show that, in a simple tight-binding model involving 3d $t_{2g}$ bands of Ti ions, the induced spin-orbit coupling in the $d_{xz}$ and $d_{yz}$ bands is cubic in momentum whereas the spin-orbit interaction in the $d_{xy}$ band has linear momentum dependence. We also find that the spin-orbit interaction in one-dimensional channels at LaAlO$_3$/SrTiO$_3$ interfaces is linear in momentum for all bands. We discuss implications of our results for transport experiments on SrTiO$_3$ surfaces and LaAlO$_3$/SrTiO$_3$ interfaces. In particular, we analyze the effect of a given spin-orbit interaction term on magnetotransport of LaAlO$_3$/SrTiO$_3$ by calculating weak anti-localization corrections to the conductance and to universal conductance fluctuations.
Modelling the ATP production in mitochondria
Creators: name: Saa, Alberto
name: Siqueira, Kellen M.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Molecular Networks (q-bio.MN)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: We revisit here the mathematical model for ATP production in mitochondria introduced recently by Bertram, Pedersen, Luciani, and Sherman (BPLS) as a simplification of the more complete but intricate Magnus and Keizer's model. We identify some inaccuracies in the BPLS original approximations for two flux rates, namely the adenine nucleotide translocator rate $J_{\rm ANT}$ and the calcium uniporter rate $J_{\rm uni}$. We introduce new approximations for such flux rates and then analyze some of the dynamical properties of the model. We infer, from exhaustive numerical explorations, that the enhanced BPLS equations have a unique attractor fixed point for physiologically acceptable ranges of mitochondrial variables and respiration inputs, as one would indeed expect from homeostasis. We determine, in the stationary regime, the dependence of the mitochondrial variables on the respiration inputs, namely the cytosolic concentration of calcium ${\rm Ca}_{\rm c}$ and the substrate fructose 1,6-bisphosphate FBP. The same dynamical effects of calcium and FBP saturations reported for the original BPLS model are observed here. We find out, however, a novel non-stationary effect which could be, in principle, physiologically interesting: some response times of the model tend to increase considerably for high concentrations of calcium and/or FBP. In particular, the larger the concentrations of ${\rm Ca}_{\rm c}$ and/or FBP, the larger the necessary time to attain homeostasis.
description: 16 pages, 6 figures. Final version to appear in the Bulletin of Mathematical Biology. Scilab codes available at http://vigo.ime.unicamp.br/atp/
Nuclear magnetic resonance studies of some 1,1-difluoro-3-phenylcyclobutane derivatives
Creators: name: Takahashi, Masaaki
Publisher: name: California Institute of Technology
Year: 1962
Subjects: Chemistry

description: 1-Difluoro-2, 2-dichloro-3-methy1-3-phenylcyclobutane has been prepared by the cycloacidition of a-methylstyrene to 1,1-difluoro2, 2-dichloroethylene. A 2 cps long-range H-F spin-spin coupling has been observed over five consecutive saturated bonds in 1,1-difluoro2, 2-dichloro-3-methyl-3-phenylcyclobutane, involving one of the fluorines at the 1-position and the protons of the 3-methyl group. Analysis of the spectrum and that of the stereospecifically labeled 4-deutero derivatives suggest that the fluorine involved is the one cis to the methyl group.

The n. m. r. studies of 1,1-difluoro-3-bromo-3-phenylcyclobutane which was obtained by bromination of 1,1-difluoro-3-phenylcyclobutane with N-bromosuccinimide indicate that this molecule has on the average a more nearly planar cyclobutane ring than that of 1,1- difluoro-2, 2-dichloro-3-methyl-3-phenylcyclobutane. The four protons of the 2- Etna 4-positions are nearly magnetically equivalent, so that the spectrum of this compound is almost that of an ABX_4 system rather than an ABX_2Y_2 system. The theoretical calculations suggest that the chemical shift difference between X and Y is on the order of 1-2 cps. The chemical shift difference between the fluorines decreases in 1,1-difluoro-2, 2-dichloro-3-methy1-3-phenylcyclobutane and 1,1- difluoro-3-bromo-3-phenylcyclobutane with increasing temperature, suggesting that rapid ring-inversion is taking place.
An investigation in the reduction of tabulated loads for bolted joints fabricated of green Douglas fir
Creators: name: Harris, Robert Blynn
Publisher: name: California Institute of Technology
Year: 1947
Subjects: subject: Civil Engineering
subject: FOS: Civil engineering

description: Because of restrictions and shortages of materials and labor caused by World War II, the lumber industry has been forced to place on the market a great deal of lumber that is in a green condition.  Consequently designers and engineers have been required to make use of this material.

Specifications currently being used for the design of bolted joints in wood structures require that the allowable loads as tabulated therein be reduced when the material used is green.  In most cases this reduction is in the order of two thirds the tabulated value, that is to say the allowable working stress is one third the tabulated value.  The conservativeness of this requirement has been questioned and it has been the purpose of this investigation to attempt to arrive at a load reduction ratio which would give a greater allowable load and a subsequent saving in labor and materials.
A mean field dynamo from negative eddy diffusivity
Creators: name: Devlen, Ebru
name: Brandenburg, Axel
name: Mitra, Dhrubaditya
Publisher: name: arXiv
Year: 2012
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Using direct numerical simulations, we verify that "flow IV" of Roberts (1972) exhibits dynamo action dominated by horizontally averaged large-scale magnetic field. With the test-field method we compute the turbulent magnetic diffusivity and find that it is negative and overcomes the molecular diffusivity, thus explaining quantitatively the large-scale dynamo for magnetic Reynolds numbers above $\approx8$. As expected for a dynamo of this type, but contrary to $α$-effect dynamos, the two horizontal field components grow independently of each other and have arbitrary amplitude ratios and phase differences. Small length scales of the mean magnetic field are shown to be stabilized by the turbulent magnetic diffusivity becoming positive at larger wavenumbers. Oscillatory decaying or growing solutions have also been found in certain wavenumber intervals and sufficiently large values of the magnetic Reynolds number. For magnetic Reynolds numbers below $\approx0.5$ the turbulent magnetic diffusivity is confirmed to be positive, as expected for all incompressible flows. Earlier claims of a dynamo driven by a modified Taylor-Green flow through negative eddy diffusivity could not be confirmed.
description: 7 pages, 9 figures, accepted to MNRAS
title: A Theoretical Proton-Proton Pair Production Cross-Section Calculation
Creators: name: Phippen, Jay W.
Publisher: name: Utah State University
Year: 1974

description: The calculation of both electron-pair and muon-pair production cross-sections was made using Feynman's quantum electrodynamics. Pseudo-scaler coupling was used between the nucleons and vector coupling was used between the photon and the Fermions. The protons were considered as Dirac particles and radiative corrections were omitted.
Eight fourth-order Feynman-Dyson diagrams were used. The subsequent sixty-four TRACES were reduced to seven basic topologically different TRACES. From the seven basic TRACES, it was possible to generate the sixty-four TRACES by the proper permutations of the variables.
With the mathematics and the corresponding computer programs written down, data (energies and momenta which represent the kinematics of the reaction) were needed. Using a Monte Carlo method, random relativistically invariant data were generated and then substituted into the computer programs from which pair production cross-sections were calculated.
Using the random nature of the data, it was possible to compare the theoretical treatment of the muon-pair production process with the experimental results of Christenson (1970). The comparison was very favorable.
Whole/cloth patch/work : looking at six quilts at the Briscoe Center
Creators: name: Scanlon, Joy
name: 0000-0002-9952-2655
Publisher: name: The University of Texas at Austin
Year: 2022
Subjects: Painting
Papermaking
Quilts
Briscoe Center
Art
Archive
Translation

description: A collection of responses to and reflections on six American quilts archived in the Dolph Briscoe Center for American History, University of Texas at Austin.
Scales of Resistance
Creators: name: Alexander, Daniel
Publisher: name: London South Bank University
Year: 2019
Subjects: Aerial
Imaging
Operational Images
Photography
3D scanning
LIDAR
Infection
Mapping
Antimicrobial Resistance
Antibiotic Resistance
Art Science
Data Visualisation

description: Scales of resistance is a piece of practice-based research by Daniel Alexander, working in collaboration with scientists at the University of Nottingham. The 7.51 minute film was scripted and directed by Alexander, and created in collaboration with the 3D imaging studio ScanLab Projects. It was exhibited at the Royal Society Summer Exhibition in July 2019. Scientists developing bacteria resistant surfaces to combat antibiotic resistance were producing image data recording the behaviour of bacteria. This data would normally be presented to the public as 3D false colour illustrations. The scientists reported that this made the data seem less real to their audiences, and carried associations of cartoons, creating barriers to engagement. Alexander comes from a photographic practice and wanted to research the possibility of operative images produced by ‘seeing machines’ such as microscopes, LIDAR scanners, Satellites etc to tell stories. This project investigated and developed methodologies for visually communicating scientific information to the public, without resorting to illustrative imagery, and researched the possibilities of re-purposing operative images for narrative means. A two-year process of bid development identified the key scientific information to be communicated, and established a methodology of using architectural visualisation software to locate images captured at micro and macro scales in accurate spatial relationship to one another. In grant public engagement funding from EPSRC and Wellcome Trust grants enabled the production of the film, which was created over a four-month period, involving close collaboration between the researcher, the scientists and the film production studio. The film utilises the concept of the zoom to move a viewer through environments they are familiar with, into the human body then up to space. The use of original operative images maintains an indexical relationship to the environments depicted - a significant development from the usual reliance on illustration to communicate scientific concepts.
Finding overlapping communities in networks using evolutionary method
Creators: name: Weihua, Zhan
name: Huahui, Chen
name: Jihong, Guan
name: Guang, Jin
Publisher: name: arXiv
Year: 2013
Subjects: subject: Social and Information Networks (cs.SI)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Community structure is a typical property of many real-world networks, and has become a key to understand the dynamics of the networked systems. In these networks most nodes apparently lie in a community while there often exists a few nodes straddling several communities. An ideal algorithm for community detection is preferable which can identify the overlapping communities in such networks. To represent an overlapping division we develop a encoding schema composed of two segments, the first one represents a disjoint partition and the second one represents a extension of the partition that allows of multiple memberships. We give a measure for the informativeness of a node, and present an evolutionary method for detecting the overlapping communities in a network.
Agenda 2063 and its Implications for Africa's Soft Power.pdf
Creators: name: Edgars, Prof Tal
Publisher: name: figshare
Year: 2022
Subjects: History of economic thought
Macroeconomic theory
Microeconomic theory
Creative arts, media and communication curriculum and pedagogy
Curriculum and pedagogy not elsewhere classified

description: This paper will examine the soft power that could possibly arise from Agenda 2063’s Aspirations 3, 4, and 5. With the exception of modest analysis of the European Union (EU), previous investigations of soft power have been state-centric and no studies have focused on the African Union’s (AU) soft power. This paper will seek to address this gap in light of negative perceptions of this region.
Detecting and Grouping Malware Using Section Hashes
Creators: name: Snoke, Timur
name: Jacobs, Michael
name: Perry, Anthony
name: Whitney, Addison
Publisher: name: Carnegie Mellon University
Year: 2023
Subjects: subject: 80309 Software Engineering
subject: FOS: Computer and information sciences

description: As technology continues to develop at a rapid pace, nation states and unaffiliated individuals alike are swiftly developing new malicious computer viruses to find vulnerabilities in computer systems and achieve their political and personal objectives. To protect against these attacks, cybersecurity companies use a variety of methods to detect malware (malicious code) from entering their systems. Current malware detection systems evaluate elements in a file or evaluate the file as a whole. New research shows that other avenues for malware detection exist, specifically, by breaking up the file into sections and then comparing the resulting parts. This blog post explains how our team developed an approach that can take a collection of known malware files and use their section hashes to identify and analyze other candidate files in a malware repository.
Virtual Works – Actual Things
Creators: name: De Assis, Paulo
name: Davies, David
name: Dorschel, Andreas
name: Goehr, Lydia D.
name: Kiloh, Kathy
name: McNulty, Jacob Michael
name: Hindrichs, Gunnar
name: Rink, John
Publisher: name: Columbia University
Year: 2018
Subjects: Music theory
Musicology
Music

description: Beyond musical works: new perspectives on music ontology and performance. What are musical works? How are they constructed in our minds? Which material things allow us to speak about them in the first place? Does a specific way of conceiving musical works limit their performative potentials? Which alternative, more productive images of musical work can be devised? Virtual Works – Actual Things addresses contemporary music ontological discourses, challenging dominant musicological accounts, questioning their authoritative foundation and moving towards dynamic perspectives devised by music practitioners and artist researchers. Specific attention is given to the relationship between the virtual multiplicities that enable the construction of an image of a musical work and the actual, concrete materials that make such a construction possible. With contributions by prominent scholars, this book is a wide-ranging and fascinating collection of essays, which will be of great interest for artistic research, contemporary musicology, music philosophy, performance studies and music pedagogy alike. Contributors: David Davies (McGill University, Montreal), Andreas Dorschel (University of the Arts Graz), Lydia Goehr (Columbia University, New York), Kathy Kiloh (OCAD University, Toronto), Jake McNulty (Columbia University, New York), Gunnar Hindrichs (University of Basel), John Rink (University of Cambridge)
Time dependent spatial entanglement in atom-field interaction
Creators: name: Christov, Ivan P.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: By using stochastic ensembles of walkers in physical and in one-body Hilbert spaces the recently proposed time-dependent quantum Monte Carlo (TDQMC) method offers the unique capability to calculate one-body density matrices at fully correlated level, without referencing the many-body quantum state. Here TDQMC is applied to study entanglement of simple systems such as Moshinsky atom (oscillator potentials) and atoms with Coulomb potentials in one spatial dimension. Our findings indicate that the dynamic entanglement of atoms exposed to powerful ultrashort laser pulse can be easily manipulated by introducing an appropriate phase modulation where the negative chirp enhances the entanglement while the positive one suppresses it. These findings can be used to explore the correlation properties of different constituents of complex quantum systems subjected to appropriately shaped laser radiation.
Specific heat and thermal conductivity of ferromagnetic magnons in Yttrium Iron Garnet
Creators: name: Pan, B. Y.
name: Guan, T. Y.
name: Hong, X. C.
name: Zhou, S. Y.
name: Qiu, X.
name: Zhang, H.
name: Li, S. Y.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The specific heat and thermal conductivity of the insulating ferrimagnet Y$_3$Fe$_5$O$_{12}$ (Yttrium Iron Garnet, YIG) single crystal were measured down to 50 mK. The ferromagnetic magnon specific heat $C$$_m$ shows a characteristic $T^{1.5}$ dependence down to 0.77 K. Below 0.77 K, a downward deviation is observed, which is attributed to the magnetic dipole-dipole interaction with typical magnitude of 10$^{-4}$ eV. The ferromagnetic magnon thermal conductivity $κ_m$ does not show the characteristic $T^2$ dependence below 0.8 K. To fit the $κ_m$ data, both magnetic defect scattering effect and dipole-dipole interaction are taken into account. These results complete our understanding of the thermodynamic and thermal transport properties of the low-lying ferromagnetic magnons.
description: 5 pages, 5 figures
Excited states of the quasi-one-dimensional hexagonal quantum antiferromagnets
Creators: name: Merdan, M.
name: Xian, Y.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We investigate the excited states of the quasi-one-dimensional quantum antiferromagnets on hexagonal lattices, including the longitudinal modes based on the magnon-density waves. A model Hamiltonian with a uniaxial single-ion anisotropy is first studied by a spin-wave theory based on the one-boson method; the ground state thus obtained is employed for the study of the longitudinal modes. The full energy spectra of both the transverse modes (i.e., magnons) and the longitudinal modes are obtained as functions of the nearest-neighbor coupling and the anisotropy constants. We have found two longitudinal modes due to the non-collinear nature of the triangular antiferromagnetic order, similar to that of the phenomenological field theory approach by Affleck. The excitation energy gaps due to the anisotropy and the energy gaps of the longitudinal modes without anisotropy are then investigated. We then compare our results for the longitudinal energy gaps at the magnetic wavevectors with the experimental results for several antiferromagnetic compounds with both integer and non-integer spin quantum numbers, and we find good agreement after the higher-order contributions are included in our calculations.
description: 7 pages, 5 figures
Association of Violence Against Female Sex Workers Who Use Drugs With Nonfatal Drug Overdose in Kazakhstan
Creators: name: El-Bassel, Nabila
name: Norcini Pala, Andrea
name: Mukherjee, Trena I.
name: McCrimmon, Tara
name: Mergenova, Gaukhar
name: Terlikbayeva, Assel
name: Primbetova, Sholpan
name: Witte, Susan S.
Publisher: name: Columbia University
Year: 2020
Subjects: Public health
Sex workers
Drugs--Overdose

description: Importance: Female sex workers (FSWs) who use drugs face increased risk of intimate partner violence (IPV) and nonpartner violence (NPV). The association between violence and drug overdose is unknown. Objective: To examine the association between IPV, NPV, and nonfatal drug overdose among FSWs who use drugs in Kazakhstan. Design, Setting, and Participants: This cross-sectional study included 400 adult FSWs in Kazakhstan who reported illicit drug use in the past year, exchanged sex for money or drugs, and reported having unprotected sex in the past 90 days. Baseline data were collected from February 2015 to May 2017 from Project Nova, an HIV prevention study among FSWs who use drugs in Kazakhstan. Data analysis was conducted from April 2019 to March 2020. Exposures: Lifetime and recent (past 90 day) experiences of physical, sexual, and psychological IPV and NPV using the Revised Conflict Tactics Scale. Subtypes of violence were identified using exploratory factor analysis. Main Outcomes and Measures: Lifetime and recent incidence of nonfatal overdose; sociodemographic characteristics as well as lifetime and recent sex work and drug use behaviors were also collected. Results: The 400 participants had a mean (SD) age of 34.1 (8.4) years. Most experienced food insecurity (358 [89.5%]) and homelessness (232 [58.0%]) in the past 90 days; one-third (130 [32.5%]) reported a history of incarceration. Most (359 [89.7%]) experienced some form of violence; 150 (37.5%) reported a lifetime nonfatal overdose, of whom 27 (18.0%) reported nonfatal overdose in the past 90 days. Lifetime severe physical violence (adjusted odds ratio [aOR], 1.27; 95% CI, 1.02-1.59; P = .03), engagement in sex work for more than 10 years (aOR, 2.54; 95% CI, 1.50-4.28; P
Contextualized Activity Tool For Enhancing Grade 7 Science Competencies
Creators: name: Maravilla, Ryan Anthony
name: Aliazas, John Vincent
Publisher: name: Zenodo
Year: 2024

description: This study aimed to assess the efficacy of using the Contextualized Activity Tool in enhancing the scientific competencies of Grade 7 students at Sto. Domingo Integrated High School during the academic year 2022-2023. The study employs a descriptive-experimental approach and includes a total of forty (40) participants, evenly distributed between twenty (20) males and twenty (20) females. The respondents' scores and ratings were examined using frequency, percentage, mean, and standard deviation. The researchers employed a paired t-test to examine the statistical significance of the differences between the pre-test and post-test scores of the participants. The study's findings indicate that the contextualized activity tool significantly improves the science competencies of grade 7 students. Moreover, the research yielded a notable disparity and an augmentation in the evaluation of science learning outcomes between the pre-test and post-test, indicating that it facilitated the students' enhanced understanding of the subject matter. The preliminary assessment indicated that most participants scored at the introductory level. Simultaneously, the post-test findings indicate that students achieved a competency level close to the expected standard after using the instrument. This illustrates that using contextualized activity tools yields a substantial disparity in their science learning outcome. This finding also indicates that integrating contextualization as a learning tool enables students to actively participate in discussions and comprehend the material and concepts in various ways. Consequently, this fosters an elevated cognitive capacity in pupils and enhances their academic achievement.