cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Non-trivial Extension of Starobinsky Inflation
Creators: name: Khoeini-Moghaddam, Salomeh
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider a non-canonic field in the context of Starobinsky inflation. We work in Einstein-frame. In this frame, the gravitational part of the action is equivalent to the Hilbert-Einstein action, plus a scalar field called scalaron. We investigate a model with a heavy scalaron trapped at the effective potential minimum, where its fluctuations are negligible. To be more explicit, we consider a Dirac-Born-Infeld (DBI) field, which is usually considered within the brane inflation context, as the non-canonic field. Although, the DBI field governs inflation through implicit dependence on Scalaron the boost factor, and other quantities are different from the standard DBI model. For appropriate parameters, this model is consistent with the Planck results.
description: 23 pages, 11 figures, Revised version
Spin-fermion mappings for even Hamiltonian operators
Creators: name: Anfossi, Alberto
name: Montorsi, Arianna
Publisher: name: arXiv
Year: 2004
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We revisit the Jordan-Wigner transformation, showing that --rather than a non-local isomorphism between different fermionic and spin Hamiltonian operators-- it can be viewed in terms of local identities relating different realizations of projection operators. The construction works for arbitrary dimension of the ambient lattice, as well as of the on-site vector space, generalizing Jordan-Wigner's result. It provides direct mapping of local quantum spin problems into local fermionic problems (and viceversa), under the (rather physical) requirement that the latter are described by Hamiltonian's which are even products of fermionic operators. As an application, we specialize to mappings between constrained-fermions models and spin 1 models on chains, obtaining in particular some new integrable spin Hamiltonian, and the corresponding ground state energies.
description: 7 pages, ReVTeX file, no figures
Irregular emission cycles in the Oe star HD 60848
Creators: name: Rauw, Gregor
name: Naze, Yael
name: Campos, Fran
name: Flo, Joan Guarro
name: Sollecchia, Umberto
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We analyse the spectroscopic and photometric variability of the Oe star HD 60848 over the last twenty five years. The spectra reveal recurrent, but irregular cycles of increased circumstellar emission lines. These cycles are highly asymmetric displaying a slow increase over about 6 years, followed by a fast decay within about 6 months. Our analysis focuses on the most recent cycle (2013 - 2020). The equivalent width and velocity separation of the emission peaks indicate variations of the outer disk radius by a factor ~ 2.2, although the variability appears more complex than expected from first principle relations for optically thin Keplerian disks. We observe a time delay between the variations of the strengths of He I 5876 on the one hand and H-alpha and H-beta on the other hand. We interpret this behaviour in a two-step disk growth scenario, where the disk first expands radially before its density increases. A difference in behaviour is also seen between H-alpha and the H I Paschen lines, with the latter displaying a more symmetric cycle, similar to the photometric variability. The rather fast decays of the H-alpha emission observed in 2001, 2009 and 2018 - 2019 suggest that the strong radiation field and early spectral type of the star lead to a faster dissipation of the disk than in later-type Be stars, as theoretically expected. We discuss X-ray observations of the star both during a high and a low-emission state. The X-ray spectrum is soft at both epochs, and the X-ray fluxes are only marginally different and remain consistent with the canonical Lx/Lbol relation of O-type stars. These results indicate that the circumstellar decretion disk of HD 60848 has essentially no impact on the star's X-ray emission, and that the latter most likely arises inside the stellar wind.
description: New Astronomy, accepted
High-resolution analysis of the ${ν_3}$ band of radiocarbon methane $^{14}CH_{4}$
Creators: name: Larnimaa, Santeri
name: Halonen, Lauri
name: Karhu, Juho
name: Tomberg, Teemu
name: Metsälä, Markus
name: Genoud, Guillaume
name: Hieta, Tuomas
name: Bell, Steven
name: Vainio, Markku
Publisher: name: arXiv
Year: 2020
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: We present the first high-resolution measurements and rotational analysis of the fundamental asymmetric stretching vibrational band ${ν_3}(F_2)$ of radiocarbon methane. A spectrometer consisting of a mid-infrared continuous-wave optical parametric oscillator and a cantilever-enhanced photoacoustic detector was employed to determine the wavenumbers of 43 rovibrational lines. A spectroscopic model could reproduce all the observed transition wavenumbers within the accuracy of the experiment. Our work contributes to the development of radiocarbon methane detectors based on laser spectroscopy.
Pilictricity: Fabrication and Optimization of Dye Sensitized Solar Cell using Pili (Canarium ovatum) Dye and Activated Carbon as Sensitizer and Counter Electrode
Creators: name: Kier Gasga
Publisher: name: figshare
Year: 2020
Subjects: subject: 90499 Chemical Engineering not elsewhere classified
subject: FOS: Chemical engineering
subject: 90608 Renewable Power and Energy Systems Engineering (excl. Solar Cells)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Dye sensitized solar cells are a new concept of photovoltaic devices that was first developed by Regan and Grätzel. In presented study, DSSC is fabricated using anatase titanium dioxide as semiconducting layer deposited on transparent conductive indium tin oxide (ITO) glass through doctor blade method. Natural dye derived from the exocarp of Pili (Canarium ovatum) was used as photosensitizer and chemically activated carbon derived from its shell was used as carbon-based counter electrode. Assembled DSSC with active surface area of 2.0 cm2 was tested under solar irradiance for open circuit photovoltage (VOC), short circuit current density (JSC), fill factor (FF), and conversion efficiency (η) at variable values of TiO2 film thickness and soaking time in dye. Runs were generated using Design-Expert® for optimization through Central Composite Design under Response Surface Methodology. Optimized DSSC parameter with 0.768 desirability was selected with TiO2 film thickness of 55.23 µm and 12 hours dye-soaking period which generated VOC of 0.446 V, JSC of 6.293 mA/cm2, FF of 0.601, η of 1.792.
Hadronic light-by-light scattering contribution to the muon g-2 from lattice QCD : Methodology
Creators: name: Hayakawa, Masashi
name: Blum, Thomas
name: Izubuchi, Taku
name: Yamada, Norikazu
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The hadronic light-by-light scattering contribution to the muon g-2 is the most troublesome component of its theoretical prediction; (1) it cannot be determined from the other measurable quantities, (2) the dimensional argument and the estimation based on hadronic models imply that the magnitude of this contribution may be comparable to the discrepancy between the standard model prediction and the experimental value. The direct approach to evaluate the hadronic light-by-light scattering contribution requires the evaluation of the correlation function of {\it four} hadronic electromagnetic currents, and the summation of it over two independent four-momenta of off-shell photons, which is far from the reach of direct lattice simulation. Here we propose an alternative method using combined (QCD + QED) lattice simulations to evaluate the hadronic light-by-light scattering contribution.
description: 6 pages, 1 figure, Talk presented at Lattice 2005 (weak matrix elements), Dublin, July 25-30, 2005, one reference added, text shortened accordingly
Harmonic Hybrid Inflation
Creators: name: Carta, Federico
name: Righi, Nicole
name: Welling, Yvette
name: Westphal, Alexander
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present a mechanism for realizing hybrid inflation using two axion fields with a purely non-perturbatively generated scalar potential. The structure of scalar potential is highly constrained by the discrete shift symmetries of the axions. We show that harmonic hybrid inflation generates observationally viable slow-roll inflation for a wide range of initial conditions. This is possible while accommodating certain UV arguments favoring constraints $f\lesssim M_{\rm P}$ and $Δϕ_{60}\lesssim M_{\rm P}$ on the axion periodicity and slow-roll field range, respectively. We discuss controlled $\mathbb{Z}_2$-symmetry breaking of the adjacent axion vacua as a means of avoiding cosmological domain wall problems. Including a minimal form of $\mathbb{Z}_2$-symmetry breaking into the minimally tuned setup leads to a prediction of primordial tensor modes with the tensor-to-scalar ratio in the range $10^{-4}\lesssim r \lesssim 0.01$, directly accessible to upcoming CMB observations. Finally, we outline several avenues towards realizing harmonic hybrid inflation in type IIB string theory.
description: 16 pages, 7 figures, 1 appendix, LaTeX. V2 accepted in JHEP
Ergodic property of Markovian semigroups on standard forms of von Neumann algebras
Creators: name: Park, Yong Moon
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We give sufficient conditions for ergodicity of the Markovian semigroups associated to Dirichlet forms on standard forms of von Neumann algebras constructed by the method proposed in Refs. [Par1,Par2]. We apply our result to show that the diffusion type Markovian semigroups for quantum spin systems are ergodic in the region of high temperatures where the uniqueness of the KMS-state holds.
description: 25 pages
Entanglement properties of multipartite entangled states under the influence of decoherence
Creators: name: Hein, M.
name: Dür, W.
name: Briegel, H. -J.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We investigate entanglement properties of multipartite states under the influence of decoherence. We show that the lifetime of (distillable) entanglement for GHZ-type superposition states decreases with the size of the system, while for a class of other states -namely all graph states with constant degree- the lifetime is independent of the system size. We show that these results are largely independent of the specific decoherence model and are in particular valid for all models which deal with individual couplings of particles to independent environments, described by some quantum optical master equation of Lindblad form. For GHZ states, we derive analytic expressions for the lifetime of distillable entanglement and determine when the state becomes fully separable. For all graph states, we derive lower and upper bounds on the lifetime of entanglement. To this aim, we establish a method to calculate the spectrum of the partial transposition for all mixed states which are diagonal in a graph state basis. We also consider entanglement between different groups of particles and determine the corresponding lifetimes as well as the change of the kind of entanglement with time. This enables us to investigate the behavior of entanglement under re-scaling and in the limit of large (infinite) number of particles. Finally we investigate the lifetime of encoded quantum superposition states and show that one can define an effective time in the encoded system which can be orders of magnitude smaller than the physical time. This provides an alternative view on quantum error correction and examples of states whose lifetime of entanglement (between groups of particles) in fact increases with the size of the system.
description: 27 pages, 11 figures
A locally anisotropic geometrical model of space-time based on CMBR
Creators: name: Labropoulos, Panagiotis G.
name: Stavrinos, Panayiotis C.
Publisher: name: arXiv
Year: 2005
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We study a locally anisotropic model of General Relativity in the framework of a more general geometrical structure than the Riemannian one. In this model the observable anisotropy of the CMBR (WMAP) is represented by a tensor of anisotropy and it is included in the metric structure of space-time. As well, some interesting special cases of spaces are considered.
description: 5 pages, 0 figures, 7th International Astronomy Conference of the Hellenic Astronomical Society, curvature and connection sections decreased, minor explanation added, fixed some typos
Nonrelativistic Open String and Yang-Mills Theory
Creators: name: Gomis, Jaume
name: Yan, Ziqi
name: Yu, Matthew
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The classical and quantum worldsheet theory describing nonrelativistic open string theory in an arbitrary nonrelativistic open and closed string background is constructed. We show that the low energy dynamics of open strings ending on n coincident D-branes in flat spacetime is described by a Galilean invariant U(n) Yang-Mills theory. We also study nonrelativistic open string excitations with winding number and demonstrate that their dynamics can be encoded into a local gauge theory in one higher dimension. By demanding conformal invariance of the boundary couplings, the nonlinear equations of motion that govern the consistent open string backgrounds coupled to an arbitrary closed background (described by a string Newton-Cartan geometry, Kalb-Ramond, and dilaton field) are derived and shown to emerge from a Galilean invariant Dirac-Born-Infeld type action.
description: 41 pages
Bar rejuvenation in S0 galaxies?
Creators: name: Barway, Sudhanshu
name: Saha, Kanak
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Based on the colour measurements from a multi-band, multi-component 2D decomposition's of S0 and spiral galaxies using SDSS images, we found that bars are bluer in S0 galaxies compared to the spiral galaxies. Most of the S0s in our sample have stellar masses $\sim L_{*}$ galaxies. The environment might have played an important role as most of the S0s with bluer bars are in the intermediate-density environment. The possibility of minor mergers and tidal interactions which occurs frequently in the intermediate-density environment might have caused either a bar to form and/or induce star formation in the barred region of S0 galaxies. The underlying discs show the usual behaviour being redder in S0s compared to spiral galaxies while the bulges are red and old for both S0 and spiral galaxies. The finding of bluer bars in S0 galaxies is a puzzling issue and poses an interesting question at numerical and theoretical studies most of which shows that the bars are long-lived structures with old stellar populations.
description: 10 pages, 7 figures, accepted for publication in MNRAS
Behavioral Economic Concepts To Encourage Healthy Eating in School Cafeterias: Experiments and Lessons From College Students
Creators: name: Just, David R.
name: Wansink, Brian
name: Mancino, Lisa
name: Guthrie, Joanne F.
name: Just, David R.
name: Wansink, Brian
name: Mancino, Lisa
name: Guthrie, Joanne F.
Publisher: name: Unknown
Year: 2008
Subjects: subject: Agricultural and Food Policy
subject: Food Consumption/Nutrition/Food Safety
subject: Health Economics and Policy
subject: Institutional and Behavioral Economics
subject: Teaching/Communication/Extension/Profession
subject: Behavioral economics
subject: healthy eating
subject: diet quality
subject: food choices
subject: school meal programs
subject: experimental economics
subject: ERS
subject: USDA.

description: Changing small factors that influence consumer choice may lead to healthier eating within controlled settings, such as school cafeterias. This report describes a behavioral experiment in a college cafeteria to assess the effects of various payment options and menu selection methods on food choices. The results indicate that payment options, such as cash or debit cards, can significantly affect food choices. College students using a card that prepaid only for healthful foods made more nutritious choices than students using either cash or general debit cards. How and when individuals select their food can also influence food choices. College students who preselected their meals from a menu board made significantly different food choices than students who ordered their meals while viewing the foods in line.
Gain-switched semiconductor laser driven soliton microcombs
Creators: name: Weng, Wenle
name: Kaszubowska-Anandarajah, Aleksandra
name: He, Jijun
name: Lakshmijayasimha, Prajwal D.
name: Lucas, Erwan
name: Liu, Junqiu
name: Anandarajah, Prince M.
name: Kippenberg, Tobias J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Dissipative Kerr solitons (DKSs) have been generated via injection locking of chipscale microresonators to continuous-wave (CW) III-V lasers. This advance has enabled fully integrated hybrid microcomb systems that operate in turnkey mode and can access microwave repetition rates. Yet, CW-driven DKS exhibits low energy conversion efficiency and high optical power threshold, especially when the repetition rate is within the microwave range that is convenient for direct detection with off-the-shelf electronics. Efficient DKS can be generated by spatiotemporally structured light (i.e., pulsed pumping), which to date however has required complex cascaded modulators for pulse synthesis. Here we demonstrate a photonic integrated approach to pulsed pumping. By actively switching the bias current of injection-locked III-V semiconductor lasers with switching frequencies in the X-band and K-band microwave ranges, we pump a crystalline and integrated microresonators with coherent picosecond laser pulses, achieving DKS generation with stable repetition rates and lowering the required average pumping power by one order of magnitude to a record-setting level of a few milliwatts. In addition, we unveil the critical role of the phase profile of the pumping pulses, and for the first time implement phase engineering on the pulsed pumping scheme by either accessing a multimode lasing regime in the gain-switching mode or applying external chirping to support robust single-soliton generation. Our work leverages the advantages of gain switching technique and pulse pumping technique, and establishes the merits of combining distinct compact frequency comb platforms that enhance the potential of energy-efficient chipscale microcombs.
Indirect Search for Dark Matter
Creators: name: Pacheco, José Antonio De Freitas
name: Peirani, Sébastien
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Possible dark matter candidates are reviewed as well as indirect search methods based on annihilation or decay channels of these particles. Neutralino is presently the best particle candidate and its annihilation produces high energy neutrinos, antiprotons, positrons and gamma-rays. To date, only upper limits on neutrino fluxes from the center of the Earth or the Sun, were established by different experiments. Antiprotons detected by the BESS collaboration, if issued from the follow up hadronization of the annihilation process, exclude neutralino masses higher than 100 GeV. The EGRET gamma-ray residual emission seen at high galactic latitudes above 1 GeV could be explained by neutralino annihilations if: i) the dark matter profile is "cored" and ii) the neutralino mass is < 50 GeV. Sterile neutrinos in the keV mass range are a possible candidate to constitute warm dark matter. These particles may provide an adequate free streaming mass able to solve "some" difficulties present in the cold dark matter scenario at small scales and could also explain the natal kick of pulsars. MeV particles, dubbed "light" dark matter, proposed to explain the extended 511 keV line emission from the galactic center will also be discussed.
description: Accepted for publication in "Gravitation & Cosmology", special edition COSMION 2004
Verification of Einstein's formula for gravitational deflection of light using observations of Galactic microlensing
Creators: name: Alexandrov, A. N.
name: Sliusar, V. M.
name: Zhdanov, V. I.
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The potential of the gravitational microlensing inside our Galaxy for testing the Einstein formula for the gravitational light deflection is discussed. For this purpose, the lens mapping is modified by introducing parameter eps, which characterizes the deviation from this formula. An example of such deviation described by a simple power law is analyzed. We formed a sample of 100 microlensing light curves using the data of the Optical Gravitational Lensing Experiment (OGLE) for 2018. The resulting eps value does not contradict the General Relativity within 1 percent errors.
description: 12 pages, 1 figure
Comparison between the first and second mass eruptions from progenitors of Type IIn supernovae
Creators: name: Kuriyama, Naoto
name: Shigeyama, Toshikazu
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Some massive stars experience episodic and intense mass loss phases with fluctuations in the luminosity. Ejected material forms circumstellar matter around the star, and the subsequent core collapse results in a Type IIn supernova that is characterized by interaction between supernova ejecta and circumstellar matter. The energy source that triggers these mass eruptions and dynamics of the outflow have not been clearly explained. Moreover, the mass eruption itself can alter the density structure of the envelope and affect the dynamics of the subsequent mass eruption if these events are repeated. A large amount of observational evidence suggests multiple mass eruptions prior to core collapse. We investigate the density structure of the envelope altered by the first mass eruption and the nature of the subsequent second mass eruption event in comparison with the first event. We deposited extra energy at the bottom of the hydrogen envelope of 15$M_\odot$ stars twice and calculated the time evolution by radiation hydrodynamical simulation code. We did not deal with the origin of the energy source, but focused on the dynamics of repeated mass eruptions from a single massive star. There are significant differences between the first and second mass eruptions in terms of the luminosity and the color. The second eruption leads to a redder burst event in which the associated brightening phase lasts longer than the first. The amount of ejected matter is different even with the same deposited energy in the first and second event, but the difference depends on the density structure of the star. Upcoming high cadence and deep transient surveys will provide us a lot of pre-supernova activities, and some of which might show multi-peaked light curves. These should be interpreted taking the effect of density structure altered by the preceding outburst events into consideration.
description: 11 pages, 14 figures, 3 tables, Accepted for publication in A&A, Abstract is slightly abridged from A&A submitted version because it exceeds 1920 characters
The Transformation of U.S. Livestock Agriculture: Scale, Efficiency, and Risks
Creators: name: MacDonald, James M.
name: McBride, William D.
name: MacDonald, James M.
name: McBride, William D.
Publisher: name: Unknown
Year: 2009
Subjects: subject: Farm Management
subject: Livestock Production/Industries
subject: Livestock
subject: dairy
subject: broilers
subject: hogs
subject: fed cattle
subject: farm structure
subject: scale economies
subject: contract agriculture
subject: CAFOs
subject: growth-promoting antibiotics

description: U.S. livestock production has shifted to much larger and more specialized farms, and the various stages of input provision, farm production, and processing are now much more tightly coordinated through formal contracts and shared ownership of assets. Important financial advantages have driven these structural changes, which in turn have boosted productivity growth in the livestock sector. But structural changes can also generate environmental and health risks for society, as industrialization concentrates animals and animal wastes in localized areas. This report relies on farm-level data to detail the nature, causes, and effects of structural changes in livestock production.
An Ensemble of Convolutional Neural Networks for Audio Classification
Creators: name: Nanni, Loris
name: Maguolo, Gianluca
name: Brahnam, Sheryl
name: Paci, Michelangelo
Publisher: name: arXiv
Year: 2020
Subjects: subject: Audio and Speech Processing (eess.AS)
subject: Machine Learning (cs.LG)
subject: Sound (cs.SD)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: In this paper, ensembles of classifiers that exploit several data augmentation techniques and four signal representations for training Convolutional Neural Networks (CNNs) for audio classification are presented and tested on three freely available audio classification datasets: i) bird calls, ii) cat sounds, and iii) the Environmental Sound Classification dataset. The best performing ensembles combining data augmentation techniques with different signal representations are compared and shown to outperform the best methods reported in the literature on these datasets. The approach proposed here obtains state-of-the-art results in the widely used ESC-50 dataset. To the best of our knowledge, this is the most extensive study investigating ensembles of CNNs for audio classification. Results demonstrate not only that CNNs can be trained for audio classification but also that their fusion using different techniques works better than the stand-alone classifiers.
Supermarket Loss Estimates for Fresh Fruit, Vegetables, Meat, Poultry, and Seafood and Their Use in the ERS Loss-Adjusted Food Availability Data
Creators: name: Buzby, Jean C.
name: Wells, Hodan Farah
name: Axtman, Bruce
name: Mickey, Jana
name: Buzby, Jean C.
name: Wells, Hodan Farah
name: Axtman, Bruce
name: Mickey, Jana
Publisher: name: Unknown
Year: 2009
Subjects: subject: Agribusiness
subject: Agricultural Finance
subject: Financial Economics
subject: Conversion factor
subject: food loss
subject: fruit
subject: meat
subject: poultry
subject: seafood
subject: supermarket
subject: vegetables

description: A certain amount of food in supermarkets is deemed unusable (“food loss”) because of moisture loss, spoilage, and other causes. This study analyzed updated food loss estimates for fresh fruit, vegetables, meat, poultry, and seafood obtained through a competitive grant with the Perishables Group, Inc. This independent consulting firm compared supplier shipment data with point-of-sale data from six large national and regional supermarket retailers to identify loss in 2005 and 2006. The new estimates, when incorporated into the ERS Loss-Adjusted Food Availability data, had little impact on aggregate per capita food loss estimates in 2006 because the new estimates were, on average, close to the previous loss assumptions. The new estimates increased annual per capita estimates of fresh fruit available at the retail level by 0.7 pounds (0.6 percent), 4.2 pounds (2.7 percent) for fresh vegetables, and 4.8 pounds (2.7 percent) for fresh meat, poultry, and seafood. The commodity-specific food loss estimates are more accurate than in previous years.
U.S. Public Agricultural Research: Changes in Funding Sources and Shifts in Emphasis, 1980-2005
Creators: name: Schimmelpfennig, David E.
name: Heisey, Paul W.
name: Schimmelpfennig, David E.
name: Heisey, Paul W.
Publisher: name: Unknown
Year: 2009
Subjects: subject: Research Methods/ Statistical Methods
subject: Agricultural research
subject: Current Research Information System
subject: CRIS
subject: State Agricultural Experiment Stations (SAES)
subject: competitive and formula funds

description: Over the years, proposals have recommended shifting the focus of public agricultural research from applied to basic research, and giving higher priority to peer-reviewed, competitively funded grants. The public agricultural research system in the United States is a Federal-State partnership, with most research conducted at State institutions. In recent years, State funds have declined, USDA funds have remained fairly steady (with changes in the composition of funding), but funding from other Federal agencies and the private sector has increased. Efforts to increase competitively awarded funds for research have fluctuated over time, as have special grants (earmarks). Along with shifts in funding sources, the proportion of basic research being undertaken within the public agricultural research system has declined. This report focuses on the way public agricultural research is funded in the United States and how changes in funding sources over the last 25 years reflect changes in the type of research pursued.
State Variations in the Food Stamp Benefit Reduction Rate for Earnings: Cross-Program Effects from TANF and SSI Cash Assistance
Creators: name: Hanson, Kenneth
name: Andrews, Margaret S.
name: Hanson, Kenneth
name: Andrews, Margaret S.
Publisher: name: Unknown
Year: 2009
Subjects: subject: Agricultural and Food Policy
subject: Food Stamp Program benefit formula
subject: Effective Benefit Reduction Rates
subject: food stamp benefit effects from TANF earning deductions
subject: effective tax rates.

description: The Food Stamp Program reduces benefits to households as their earnings rise. This reduction is affected by household participation in other Government assistance programs (cross-program effects) and by the wide variation in State-specific reduction rates for earnings in Temporary Assistance for Needy Families (TANF). This study shows that, for food stamp recipients who also received cash benefits through TANF in 2005, an extra dollar of earnings led to a change in food stamp benefits ranging from a reduction of 36 cents to an increase of 9 cents. On average across all States, the overall reduction rate for food stamp benefits and TANF cash benefits was about 70 percent, or about double the benefit reduction rate for a household that received only food stamp benefits. Even with this high benefit reduction rate, households received larger net incomes by working and earning income. Cross-program effects and State-level variability in food stamp benefits are important considerations in integrating Government assistance programs into a support system for low-income households.
China's Ongoing Agricultural Modernization: Challenges Remain After 30 Years of Reform
Creators: name: Lohmar, Bryan
name: Gale, H. Frederick
name: Tuan, Francis C.
name: Hansen, James M.
name: Lohmar, Bryan
name: Gale, H. Frederick
name: Tuan, Francis C.
name: Hansen, James M.
Publisher: name: Unknown
Year: 2009
Subjects: subject: Agricultural and Food Policy
subject: International Relations/Trade
subject: Production Economics
subject: China
subject: economic reform
subject: economic development
subject: agricultural production
subject: agricultural trade

description: Thirty years ago, China began implementing a series of reforms to improve efficiency in agricultural production. These, and subsequent, reforms reshaped China’s position in the world economy. China’s rapid economic development and transformation from a planned to a market-oriented economy, however, has reached a stage where further efficiency gains in agricultural production will likely hinge on the development of modern market-supporting institutions. The development of market-supporting institutions in China will bring about long-term and sustainable benefits to producers and consumers in China and the global agricultural economy. This report provides an overview of current issues in China’s agricultural development, policy responses to these issues, and the effects of these policies on China’s growing role in international markets.
An Illustrated Guide to Research Findings from USDA's Economic Research Service
Creators: name: Economic Research Service
name: Economic Research Service
Publisher: name: Unknown
Year: 2009
Subjects: subject: Agricultural and Food Policy
subject: Crop Production/Industries
subject: Farm Management
subject: Food Consumption/Nutrition/Food Safety
subject: Food Security and Poverty
subject: Farm Policy
subject: Risk Management
subject: Food Consumption
subject: Food Nutrition Assistance
subject: Conservation Policy
subject: Food Assistance and Nutrition Programs
subject: Food Security
subject: Agricultural Productivity in the U.S.
subject: Farm Structure
subject: Rural Population
subject: Environmental Interactions
subject: Invasive Species Management
subject: Bioenergy
subject: Global Food Markets
subject: NAFTA
subject: Organic Agriculture

description: This book contains a sampling of recent ERS research illustrating the breadth of the Agency’s research on current policy issues: from biofuels to food consumption to land conservation to patterns of trade for agricultural products. What you won’t find in this collection is any mention of economists’ favorite analytic tools (regression analyses, for example, and coefficients of variation). We wanted this guide to highlight results, not process. Even so, the findings on display here are all based on rigorous and robust application of such tools as well as use of the latest econometric techniques.
The Size and Pervasiveness of Ly$α$-UV Spatial Offsets in Star-Forming Galaxies at $z\sim6$
Creators: name: Lemaux, B. C.
name: Fuller, S.
name: Bradač, M.
name: Pentericci, L.
name: Hoag, A.
name: Strait, V.
name: Treu, T.
name: Alvarez, C.
name: Bolan, P.
name: Gandhi, P. J.
name: Jones, T.
name: Mason, C.
name: Pelliccia, D.
name: Ribeiro, B.
name: Ryan, R. E.
name: Schmidt, K. B.
name: Vanzella, E.
name: Khusanova, Y.
name: Fèvre, O. Le
name: Guaita, L.
name: Hathi, N. P.
name: Koekemoer, A.
name: Pforr, J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We study the projected spatial offset between the ultraviolet continuum and Ly$α$ emission for 65 lensed and unlensed galaxies in the Epoch of Reionization ($5\leq z\leq7$), the first such study at these redshifts, in order to understand the potential for these offsets to confuse estimates of the Ly$α$ properties of galaxies observed in slit spectroscopy. While we find that ~40% of galaxies in our sample show significant projected spatial offsets ($|Δ_{Lyα-UV}|$), we find a modest average offset of 0.61$\pm$0.08 kpc. A small fraction of our sample, ~10%, exhibits offsets of 2-4 kpc, sizes that are larger than the effective radii of typical galaxies at these redshifts. An internal comparison and a comparison to studies at lower redshift yielded no significant evidence of evolution of $|Δ_{Lyα-UV}|$ with redshift. In our own sample, UV-bright galaxies showed offsets a factor of three greater than their fainter counterparts, 0.89$\pm$0.18 vs. 0.27$\pm$0.05 kpc, respectively. We argue that offsets are likely not the result of merging processes, but are rather due to internal anisotropic processes resulting from stellar feedback facilitates Ly$α$ fluorescence and/or backscattering from nearby or outflowing gas. The reduction in the Ly$α$ flux due to offset effects for various observational setups was quantified through mock observations of simple simulations. It was found that the loss of Ly$α$ photons for galaxies with average offsets is not, if corrected for, a limiting factor for all but the narrowest slit widths (<0.4''). However, for the largest offsets, if such offsets are mostly perpendicular to the slit major axis, slit losses were found to be extremely severe in cases where slit widths of $\leq$1'' were employed, such as those planned for James Webb Space Telescope/NIRSpec observations. (abridged)
description: 21 pages, 7 figures, 2 tables. Updated with the accepted MNRAS version that includes minor changes to the text and two tables
Evaluating New Beef Production Technologies and Their Impact on the Sustainability of a Grazing System: A Stochastic Dynamic Model
Creators: name: Alford, Andrew R.
name: Cacho, Oscar J.
name: Griffith, Garry R.
name: Alford, Andrew R.
name: Cacho, Oscar J.
name: Griffith, Garry R.
Publisher: name: Unknown
Year: 2004
Subjects: subject: Farm Management
subject: Production Economics
subject: farm level evaluation
subject: genetic trait
subject: stochastic dynamic model

description: Net feed efficiency (NFE) technology is expected to improve the productivity of grazing systems in Australia's southern beef producing regions. The extended time path required for implementation of this genetic technology into commercial herds and the influence of climatic variability on the pasture base are important issues to address in estimating the benefits of this technology at the farm level. NFE also has the potential to impact on the sustainability of the grazing systems in terms of maintaining adequate pasture cover. These issues are investigated by developing a stochastic dynamic simulation model. The bioeconomic model includes pasture, animal production, herd dynamics and economic sub-models. In this paper the model is presented and the implications of the results for adoption of the technology are discussed.
On the Economics of Precision Agriculture: Technical, Informational and Environmental Aspects
Creators: name: Anvec, Tihomir
name: Whelan, Brett
name: McBratney, Alex
name: Anvec, Tihomir
name: Whelan, Brett
name: McBratney, Alex
Publisher: name: Unknown
Year: 2004
Subjects: subject: Agribusiness
subject: Environmental Economics and Policy
subject: economics
subject: precision agriculture
subject: environment
subject: information

description: The paper presents an integrated framework of biophysical and economic modelling as a novel approach towards precision agriculture research. A theoretical economic model determining the optimal number of precision agriculture management units within a given field of land is presented. The model is expanded to account for the value of the research information provided be the precision agriculture researchers. Since the inherent environmental values associated with precision agriculture are often omitted from the economic analysis, an attempt is made to incorporate these values into the model. The versions of the model are empirically tested using the data available.
SSumM: Sparse Summarization of Massive Graphs
Creators: name: Lee, Kyuhan
name: Jo, Hyeonsoo
name: Ko, Jihoon
name: Lim, Sungsu
name: Shin, Kijung
Publisher: name: arXiv
Year: 2020
Subjects: subject: Databases (cs.DB)
subject: Social and Information Networks (cs.SI)
subject: FOS: Computer and information sciences
subject: H.2.8

description: Given a graph G and the desired size k in bits, how can we summarize G within k bits, while minimizing the information loss? Large-scale graphs have become omnipresent, posing considerable computational challenges. Analyzing such large graphs can be fast and easy if they are compressed sufficiently to fit in main memory or even cache. Graph summarization, which yields a coarse-grained summary graph with merged nodes, stands out with several advantages among graph compression techniques. Thus, a number of algorithms have been developed for obtaining a concise summary graph with little information loss or equivalently small reconstruction error. However, the existing methods focus solely on reducing the number of nodes, and they often yield dense summary graphs, failing to achieve better compression rates. Moreover, due to their limited scalability, they can be applied only to moderate-size graphs. In this work, we propose SSumM, a scalable and effective graph-summarization algorithm that yields a sparse summary graph. SSumM not only merges nodes together but also sparsifies the summary graph, and the two strategies are carefully balanced based on the minimum description length principle. Compared with state-of-the-art competitors, SSumM is (a) Concise: yields up to 11.2X smaller summary graphs with similar reconstruction error, (b) Accurate: achieves up to 4.2X smaller reconstruction error with similarly concise outputs, and (c) Scalable: summarizes 26X larger graphs while exhibiting linear scalability. We validate these advantages through extensive experiments on 10 real-world graphs.
description: to be published in the 26th ACM SIGKDD International Conference on Knowledge Discovery and Data Mining (KDD '20)
A Simple Multiscale Method for Mean Field Games
Creators: name: Li, Haoya
name: Fan, Yuwei
name: Ying, Lexing
Publisher: name: arXiv
Year: 2020
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: This paper proposes a multiscale method for solving the numerical solution of mean field games which accelerates the convergence and addresses the problem of determining the initial guess. Starting from an approximate solution at the coarsest level, the method constructs approximations on successively finer grids via alternating sweeping, which not only allows for the use of classical time marching numerical schemes but also enables applications to both local and nonlocal problems. At each level, numerical relaxation is used to stabilize the iterative process. A second-order discretization scheme is derived for higher-order convergence. Numerical examples are provided to demonstrate the efficiency of the proposed method in both local and nonlocal, 1-dimensional and 2-dimensional cases.
description: 20 pages, 24 figures; v2: final version accepted at Journal of Computational Physics
Meta Learning for Support Recovery in High-dimensional Precision Matrix Estimation
Creators: name: Zhang, Qian
name: Zheng, Yilin
name: Honorio, Jean
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: In this paper, we study meta learning for support (i.e., the set of non-zero entries) recovery in high-dimensional precision matrix estimation where we reduce the sufficient sample complexity in a novel task with the information learned from other auxiliary tasks. In our setup, each task has a different random true precision matrix, each with a possibly different support. We assume that the union of the supports of all the true precision matrices (i.e., the true support union) is small in size. We propose to pool all the samples from different tasks, and \emph{improperly} estimate a single precision matrix by minimizing the $\ell_1$-regularized log-determinant Bregman divergence. We show that with high probability, the support of the \emph{improperly} estimated single precision matrix is equal to the true support union, provided a sufficient number of samples per task $n \in O((\log N)/K)$, for $N$-dimensional vectors and $K$ tasks. That is, one requires less samples per task when more tasks are available. We prove a matching information-theoretic lower bound for the necessary number of samples, which is $n \in Ω((\log N)/K)$, and thus, our algorithm is minimax optimal. Then for the novel task, we prove that the minimization of the $\ell_1$-regularized log-determinant Bregman divergence with the additional constraint that the support is a subset of the estimated support union could reduce the sufficient sample complexity of successful support recovery to $O(\log(|S_{\text{off}}|))$ where $|S_{\text{off}}|$ is the number of off-diagonal elements in the support union and is much less than $N$ for sparse matrices. We also prove a matching information-theoretic lower bound of $Ω(\log(|S_{\text{off}}|))$ for the necessary number of samples. Synthetic experiments validate our theory.
Generalized Tri-bimaximal Neutrino Mixing and Its Sensitivity to Radiative Corrections
Creators: name: Luo, Shu
name: Xing, Zhi-zhong
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We argue that the tri-bimaximal neutrino mixing pattern $V_0$ or its generalized form $V'_0$, which includes two arbitrary Majorana phases of CP violation, may result from an underlying flavor symmetry at a superhigh energy scale close to the seesaw scale ($\sim 10^{14}$ GeV). Taking the working assumption that three neutrino masses are nearly degenerate, we calculate radiative corrections to $V_0$ and $V'_0$ in their evolution down to the electroweak scale ($\sim 10^2$ GeV). Three mixing angles of $V_0$ or $V'_0$ are essentially stable against radiative corrections in the standard model (SM). In the minimal supersymmetric standard model (MSSM), however, $V_0$ is in general disfavored and $V'_0$ can be compatible with current neutrino oscillation data if its two Majorana phases $α^{}_1$ and $α^{}_2$ are properly fine-tuned. We also find that it is possible to radiatively generate the CP-violating phase $δ$ from $α^{}_1$ and $α^{}_2$, and δmay keep on staying at its fixed point in either the SM or the MSSM.
description: RevTex 14 pages, 2 figures. Table I corrected. Minor changes made. More discussions added