cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Black hole superradiant instability from ultralight spin-2 fields
Creators: name: Brito, Richard
name: Grillo, Sara
name: Pani, Paolo
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Ultralight bosonic fields are compelling dark-matter candidates and arise in a variety of beyond-Standard-Model scenarios. These fields can tap energy and angular momentum from spinning black holes through superradiant instabilities, during which a macroscopic bosonic condensate develops around the black hole. Striking features of this phenomenon include gaps in the spin-mass distribution of astrophysical black holes and a continuous gravitational-wave~(GW) signal emitted by the condensate. So far these processes have been studied in great detail for scalar fields and, more recently, for vector fields. Here we take an important step forward in the black-hole superradiance program by computing, analytically, the instability time scale, the direct GW emission, and the stochastic background, in the case of massive tensor (i.e., spin-$2$) fields. Our analysis is valid for any black hole spin and for small boson masses. The instability of massive spin-$2$ fields shares some properties with the scalar and vector cases, but its phenomenology is much richer, for example there exist multiple modes with comparable instability time scales, and the dominant GW signal is hexadecapolar rather than quadrupolar. Electromagnetic and GW observations of spinning black holes in the mass range $M\in(1,10^{10})M_\odot$ can constrain the mass of a putative spin-$2$ field in the range $10^{-22} \lesssim m_b\,{\rm c^2/eV} \lesssim 10^{-10}$. For $10^{-17}\lesssim m_b\,{\rm c^2/eV}\lesssim 10^{-15}$, the space mission LISA could detect the continuous GW signal for sources at redshift $z=20$, or even larger.
description: 13 pages, 4 Figures; v3: minor changes to match published version in Physical Review Letters
Forecasting convective initiation in the STEPS domain
Creators: name: Navarro, Brad
name: Weisman, Morris
name: Miller, Jay
name: Holzhauer, Vicki
name: Windham, Tom
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2000

The Severe Thunderstorm Electrification and Precipitation Study (STEPS) was carried out over the region of the Colorado/Kansas border during the summer of 2000. Its goal was to study the precipitation and electrification properties associated with thunderstorms over the high plains. To fulfill this goal, several mobile observing systems were employed to collect data on the storms. As a direct result, the use of a nowcaster was necessary. Nowcasting during STEPS required an understanding of the conditions favorable for convective initiation and convective evolution. This paper explores and discusses the general guidelines that can be used to simplify the convective forecast problem. As the results of this paper will show, the use of several parameters in STEPS made forecasting convection more accurate and simple. But the limitations of applying these guidelines are apparent when used in areas other than the high plains.
title: Local scale assessment of climate change and its impacts in the Highlands and Islands of Scotland
Creators: name: Coll, John
Publisher: name: The Open University
Year: 2007

description: The global climate is warming and there is consensus that recent warming trends will amplify, as the present century progresses, in response to a continued build up of atmospheric greenhouse gas (GHG) concentrations. However, there are limitations associated with Global Climate Model (GCM) and Regional Climate Model (RCM) outputs for topographically diverse regions. Strategic management decisions relating to maritime upland communities require locally resolved projections of change across a range of elevations, which are not supplied by the present generation of models. Here, some of these challenges are addressed via a series of distinctive analyses. Quality controlled baseline station data are used to assess performance outputs for seasonal mean values of temperature and precipitation from an RCM at representative locations across the region. In the case of temperature these inter-comparisons indicate a warm bias in the RCM-simulated seasonal minima for the transition seasons of spring and autumn, whereas for summer maxima there is a cold bias in RCM-simulated values. RCM-generated outputs of future changes to temperature and precipitation are then variably combined with station data to model altitudinal changes at western and eastern upland locations. These analyses indicate a substantial upward migration in key seasonal temperature isotherms associated with present vegetation zones for the climate change scenarios used. This approach is then extended by applying selected outputs to conduct Climate Change Impact Assessments (CCIAs) for the scenarios used in a series of upland case studies. The analyses flag a number of remaining research challenges. Principally, these are that scale-dependent controls on local topo-climates are not adequately captured in the GCM driven RCM projection. While the approach delivers more refined local-scale projections of possible change across a range of elevations than has hitherto been available, residual uncertainties associated with the use of GCM/RCM outputs remain.
The relationship between the electric field and radar reflectivity of thunderstorms producing positive cloud-to-ground lightning in STEPS
Creators: name: Martinez, Maribel
name: Miller, Jay
name: Weisman, Morris
name: MacGorman, Donald
name: Rust, Dave
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2000

The Severe Thunderstorm Electrification and Precipitation Study (STEPS) was held between May 22-July 16, 2000 in Goodland, Kansas. One of the goals was to get a better understanding of predominantly positive cloud-to-ground flashes in thunderstorms on the High Plains. This paper discusses the relationships of the electric field and radar reflectivity of three different soundings taken during the project. All showed electric fields different from those found in storms with predominantly -CG lightning. An extra upper positive layer was seen in the anvil flight and all +CG lightning was located between the anvil and core during the dissipating stage of the storm. A core flight showed an inverted polarity and all benchmark regions were in the updraft portion of the storm. The second core showed that no apparent negative electric field charge layer was present and all +CG lightning was clustered in regions of highest reflectivity. This cell had produced a tornado just 30 minutes prior to the sounding.
Comment on 'Quantum principle of relativity'
Creators: name: Horodecki, Ryszard
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Dragan and Ekert in the paper (2020 \emph{New. J. Phys.} \textbf{22} 033038) presented 'quantum principle of relativity' (QPR) based on Galilean principle of relativity, which involves both superluminal $G_S$ and subluminal $G_s$ families of observers and argue that then they are considered on the same footing it 'implies the emergence of non-deterministic dynamics, together with complex probability amplitudes and multiple trajectories.'. Here we discuss QPR in the context of Heisenberg's classification of the fundamental physical theoretical models under the role universal constants of nature: Planck's constant $h$ and speed of light $c$. We point out that both the superluminal and subluminal branches are separable in the sense that there is no mathematical coherent formalism that connect both branches. This, in particular, implies that the QPR is incomplete.
description: Title changed, slightly expanded, minor corrections
Una pupilla diffrattiva per guardare Alpha Centauri
Creators: Valentina Guglielmo
Publisher: name: Media Inaf
Year: 2021

Finanziato dal governo australiano lo sviluppo di parte della missione Toliman, un telescopio spaziale progettato per scoprire tutto sul sistema stellare più vicino alla Terra: quello di Alpha Centauri e Proxima Centauri. Per cercare pianeti abitabili il telescopio si baserà su un innovativo sistema ottico chiamato “pupilla di diffrazione”. Con un commento di Roberto Ragazzoni
Wavelet transforms of chromospheric timeseries data
Creators: name: Levy, Lorenza
name: McIntosh, Scott
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2000

We applied wavelet transforms to a remarkable chromospheric time-series dataset, obtained on 25 April 1997 by the SUMER spectrograph on board the SOHO spacecraft, which shows a strong oscillatory signal. This signal is attributed by many as belonging to upward propagating waves generated in the photosphere. The dataset consists of one continuum band (C I - 1043 A) and two emission lines (C II - 1037.0 A and O VI - 1037.6 A) observed simultaneously for some 2 hours. Previous thorough analysis of this dataset by Wikstol et al. (2000, ApJ, V.531, p1150) has detailed many temporal characteristics of these waves. However, application of wavelet transforms has allowed us to gain information about, not only the temporal nature of the waves, but frequency behavior also. The addition of frequency shifting of the waves with altitude allows us to further probe the atmosphere and compile a picture of the Sun's atmosphere during these observations.
Does the modernisation of food chains reduce food losses and waste in developing countries? Insights from the tomato chain in Colombia
Creators: name: Chaboud, G.
name: Moustier, P.
name: Chaboud, G.
name: Moustier, P.
Publisher: name: Unknown
Year: 2018
Subjects: International Relations/Trade

description: In developing countries, food losses and waste (FLW) are expected to be high at post-harvest stages (e.g. storage, transport, retail) due to poor infrastructure, poor post-harvest handling and technical constraints, especially for perishable products. The paper intends: i) to assess the volume of unsold food products (i.e. quantitative FLW) for the tomato chain supplying Cali, and ii) to identify the determining factors, in particular, the nature of marketing chains. It is based on primary data collected along the tomato supply chain of Cali in Colombia, from production to retail stage. We find relatively low levels of FLW: 12% for farmers on average, less than 5% for traders. The lowest levels are observed when farmers combine different food chains, i.e. supermarket and non-supermarket driven. This behaviour is adapted to the diversity of social and economic characteristics of consumers. It is discussed in reference to theories of plural forms of governance in food chains. Key words Food losses and waste, food supply chain, supermarkets, plural forms, market complementarities, case study Acknowledgement : This article is an outcome of a PhD thesis at the Doctoral School of Economics and Management in Montpellier and at the French Agricultural Research Centre for International Development (Cirad). The authors gratefully acknowledge the CIAT in Cali for the material and financial support provided for data collection and for the dissemination and discussion of the results with the stakeholders. A special thanks to Guy Henry for his helpful advices in the field. We are sincerely grateful to the many stakeholders of the tomato chain that took the time to participate in the survey.
TorchIO: A Python library for efficient loading, preprocessing, augmentation and patch-based sampling of medical images in deep learning
Creators: name: Pérez-García, Fernando
name: Sparks, Rachel
name: Ourselin, Sébastien
Publisher: name: arXiv
Year: 2020
Subjects: subject: Image and Video Processing (eess.IV)
subject: Artificial Intelligence (cs.AI)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Processing of medical images such as MRI or CT presents unique challenges compared to RGB images typically used in computer vision. These include a lack of labels for large datasets, high computational costs, and metadata to describe the physical properties of voxels. Data augmentation is used to artificially increase the size of the training datasets. Training with image patches decreases the need for computational power. Spatial metadata needs to be carefully taken into account in order to ensure a correct alignment of volumes. We present TorchIO, an open-source Python library to enable efficient loading, preprocessing, augmentation and patch-based sampling of medical images for deep learning. TorchIO follows the style of PyTorch and integrates standard medical image processing libraries to efficiently process images during training of neural networks. TorchIO transforms can be composed, reproduced, traced and extended. We provide multiple generic preprocessing and augmentation operations as well as simulation of MRI-specific artifacts. Source code, comprehensive tutorials and extensive documentation for TorchIO can be found at https://torchio.rtfd.io/. The package can be installed from the Python Package Index running 'pip install torchio'. It includes a command-line interface which allows users to apply transforms to image files without using Python. Additionally, we provide a graphical interface within a TorchIO extension in 3D Slicer to visualize the effects of transforms. TorchIO was developed to help researchers standardize medical image processing pipelines and allow them to focus on the deep learning experiments. It encourages open science, as it supports reproducibility and is version controlled so that the software can be cited precisely. Due to its modularity, the library is compatible with other frameworks for deep learning with medical images.
description: Published in Computer Methods and Programs in Biomedicine
Knot adjacency and fibering
Creators: name: Kalfagianni, Efstratia
name: Lin, Xiao-Song
Publisher: name: arXiv
Year: 2004
Subjects: subject: Geometric Topology (math.GT)
subject: FOS: Mathematics

description: It is known that the Alexander polynomial detects fibered knots and 3-manifolds that fiber over the circle. In this note, we show that when the Alexander polynomial becomes inconclusive, the notion of "knot adjacency", studied in the paper "Knot adjacency, genus and essential tori" by the authors, can be used to obtain obstructions to fibering of knots and of 3-manifolds. As an application, given a fibered knot K', we construct infinitely many non-fibered knots that share the same Alexander module and the same Vassiliev invariants up to certain orders with K'. Our construction also provides, for every natural number n, examples of irreducible 3-manifolds that cannot be distinguished by the Cochran-Melvin finite type invariants of order < n.
description: 18 pages. To appear in Transactions of the AMS
Centris (Paracentris) ferrisi Cockerell 1924
Creators: name: Pedro, Diego De
name: Ceccarelli, Fadia Sara
name: Sagot, Philippe
name: López-Reyes, Eulogio
name: Mullins, Jessica L.
name: Mérida-Rivas, Jorge A.
name: Falcon-Brindis, Armando
name: Griswold, Terry
name: Ascher, John S.
name: Gardner, Joel
name: Ayala, Ricardo
name: Vides-Borrell, Eric
name: Vandame, Rémy
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Apidae
Centris
Centris ferrisi

description: Centris (Paracentris) ferrisi Cockerell, 1924
Endemic
[Holotype: CASC; ♂ La Paz, Baja California Sur, Mexico; June 29, 1919]
This species is endemic to the BCP. ASUHIC reports seven specimens collected in the Central Desert, Sarcocaulescent Shrubland, and Gulf Coast in July 1968 (SCAN 2023). There are also specimens in SEMC from the Gulf Coast Region collected in September 1983. The CARCIB team collected one female in the Gulf Coast in July 2017, and the BBPT team captured one female in the Vizcaíno Desert in March 2021 (MABC). See fig. 87.
description: Published as part of Pedro, Diego De, Ceccarelli, Fadia Sara, Sagot, Philippe, López-Reyes, Eulogio, Mullins, Jessica L., Mérida-Rivas, Jorge A., Falcon-Brindis, Armando, Griswold, Terry, Ascher, John S., Gardner, Joel, Ayala, Ricardo, Vides-Borrell, Eric & Vandame, Rémy, 2024, Revealing the Baja California Peninsula's Hidden Treasures: An Annotated checklist of the native bees (Hymenoptera: Apoidea: Anthophila), pp. 1-391 in Zootaxa 5522 (1) on page 148, DOI: 10.11646/zootaxa.5522.1.1, http://zenodo.org/record/13920532
Un tuffo nello space debris per Solar Orbiter
Creators: Claudia Mignone
Publisher: name: Media Inaf
Year: 2021

Nelle prime ore di sabato 27 novembre, Solar Orbiter passerà a soli 460 chilometri dalla Terra prima di iniziare la fase scientifica principale della missione, dedicata a svelare i misteri del Sole e la sua connessione con la meteorologia spaziale. Una manovra non priva di rischi, poiché la sonda dovrà attraversare le due “nuvole” di detriti spaziali che circondano il nostro pianeta
Crosswalk patrol : Encouraging safer use of crosswalks
Creators: name: Ching, Phoebe
name: Henry, Rachel
name: Yeung, Clarice
name: Xu, Ellen
Publisher: name: The University of British Columbia
Year: 2017

description: In an effort to prevent and reduce accidents that might happen within the campus of the University of British Columbia, our research was interested in what kind of interventions could be put into place to increase safe pedestrian behaviour involving the use of crosswalks. Using an observational study design, we investigated whether the presence of a visual prompt (road sign) or manipulating the feeling of being monitored on their behaviour would increase safe or unsafe crosswalk usage by pedestrians. We hypothesized the following: 1. The presence of only the visual cue would result in no significant difference from control, and 2. When pedestrians feel like they are being monitored, they are more likely to use the crosswalk safely. Our results supported both of our hypotheses. Our main finding was that individuals are more likely to use the crosswalk safely when there was one person wearing a safety vest and holding up a sign that encouraged safe crosswalk behaviour. Our results further revealed that having more than one person with a sign does not significantly increase safe crosswalk behavior, but it did reduce the number of people engaging in unsafe crosswalk behaviour than displaying the sign alone. We discuss the implications of this study with regards to suggestions for creating a safer environment for pedestrians and to reduce unsafe road crossing behaviours. Disclaimer: “UBC SEEDS provides students with the opportunity to share the findings of their studies, as well as their opinions, conclusions and recommendations with the UBC community. The reader should bear in mind that this is a student project/report and is not an official document of UBC. Furthermore readers should bear in mind that these reports may not reflect the current status of activities at UBC. We urge you to contact the research persons mentioned in a report or the SEEDS Coordinator about the current status of the subject matter of a project/report.”
Economic analysis of small-scale poultry production in Kenyan medium-sized cities of Kisumu and Thika
Creators: name: Omondi, S.O.
name: Omondi, S.O.
Publisher: name: Unknown
Year: 2018
Subjects: Livestock Production/Industries

description: Studies have shown conflicting results regarding the importance of urban agricultural production on household food security. This study, while recognizing the importance of food security role of urban agriculture, focuses on the economic and household income aspects of urban agriculture. This is achieved using a sample of indigenous chicken producers in the medium-sized cities of Kisumu and Thika, in Kenya. Urban indigenous chicken production serves a dual role of food provision and income generation. Therefore, this study asserts that the extent of importance of urban agriculture is contingent on the type of urban agricultural activities practiced. Multivariate regression model shows that access to high value markets and market information significantly affects profitability of indigenous chicken farming. To obtain the desired welfare benefits for smallholder poultry farmers, policies should be introduced to facilitate their access to high value markets. Such policies should also include provision of affordable high yielding poultry breeds, facilitation for formation of farmer groups, and training farmers on feed production. Acknowledgement : The author would like to thank Magnus Jirstr m and Mikael Hammarskj ld for their valuable comments on earlier drafts. He is grateful for financial support by the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS) [grant number225-2012-609]; and the Swedish International Development Cooperation Agency (SIDA) [grant number SWE-2011-028].
Il pieno, grazie. Di iodio
Creators: Valentina Guglielmo
Publisher: name: Media Inaf
Year: 2021

ThrustMe ha testato per la prima volta con successo nello spazio, integrato in un cubesat, un sistema di propulsione elettrica alimentato a iodio. La nuova soluzione è ideale per i piccoli satelliti perché si adatta bene alla miniaturizzazione del sistema di propulsione. I risultati sono stati pubblicati oggi su Nature
Relaxed eddy accumulation flux measurements of wound-induced oxygenated VOCs from a cut hay field in Austria
Creators: name: Johnson, Theresa
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2000

The study of oxygenated volatile organic compounds (OVOCs) is critical to understanding total VOC emission fluxes. OVOC emissions play an important role in regional tropospheric chemistry, especially as precursors for the formation of photochemical smog and tropospheric ozone (O3). Past studies have focused mainly on forest canopy fluces of VOCs. Current emission model parameters include forest sources, but do not take into account the possible area source of OVOCs emitted during wounding episodes such as hay harvesting. I analyzed 10 gas cartridge samples taken above a harvested hay field in Austria using the relaxed eddy accumulation (REA) technique. The REA technique involves separating air samples by updrafts and downdrafts. The general theory behind REA is that if an emission flux is present above an area, the concentration of compounds in the updraft samples should be greater than the concentration of compounds in the downdraft sample. Using gas chromotography coupled with a flame ionization detector, I found the compounds acetaldehyde, methanol, acetone, and hexenal in the samples, but I was not able to determine if there was a significant flux of these compounds. Preliminary results indicated that our method of analyzing OVOCs is not sensitive enough yet to successfully employ the REA technique for measuring OVOC fluxes. In particular, the role of humidity in both sample collection and analysis, and the effects of long-term storage need to be further investigated.
The cultural form of saving as a group: Flexible savings group strategies in the new South Africa
Creators: name: Greene, Katrina Tomar
Publisher: name: American University
Year: 2023

description: This dissertation examines the adaptation and innovation of the cultural form of saving as a group by black women who are members of savings groups in the townships of Langa, Guguletu, and Khayelitsha in Cape Town, South Africa. The aim of this dissertation is to determine if and how the members of savings groups have created flexible savings group strategies to participate in the opportunities of the new South Africa. It also explores how group members express Ubuntu (humanity) toward one another and how women receive empowerment from their participation in savings groups. I gathered research data on the practices and activities of three types of savings groups: (1) savings and credit associations (SCAs), (2) black women's long-term investment groups, and (3) small housing savings and finance groups. This involved conducting in-depth semi-structured interviews with two kinds of informants. I conducted sixty-three interviews with members of one or more of the three types of savings groups and fourteen interviews with specialized resource persons, such as representatives of non-governmental organizations and private sector business consultants/managers who worked with many of the savings groups. I also engaged in participant observation of various savings group meetings, workshops, and other activities. My findings illustrate that the members of black women's long-term investment groups and small housing savings and finance groups adapted flexible SCA practices, which acted as local accumulation strategies that recombined and selectively used existing and new patterns of behavior. Such practices enabled them to engage in new black economic empowerment and housing development initiatives. The priorities and goals of the members of the investment and housing savings groups also resulted in their flexible expression of Ubuntu that often modified and/or limited established forms of assistance among group members. However, the members of all three types of savings groups gained empowerment, especially economic empowerment, from such groups and used these savings groups to respond to the gendered division of labor that placed women as the primary caretakers of the household.
Spectro-Imaging Forward Model of Red and Blue Galaxies
Creators: name: Fagioli, Martina
name: Tortorelli, Luca
name: Herbel, Jörg
name: Zürcher, Dominik
name: Refregier, Alexandre
name: Amara, Adam
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: For the next generation of spectroscopic galaxy surveys, it is important to forecast their performances and to accurately interpret their large data sets. For this purpose, it is necessary to consistently simulate different populations of galaxies, in particular Emission Line Galaxies (ELGs), less used in the past for cosmological purposes. In this work, we further the forward modeling approach presented in Fagioli et al. 2018, by extending the spectra simulator Uspec to model galaxies of different kinds with improved parameters from Tortorelli et al. 2020. Furthermore, we improve the modeling of the selection function by using the image simulator Ufig. We apply this to the Sloan Digital Sky Survey (SDSS), and simulate $\sim157,000$ multi-band images. We pre-process and analyse them to apply cuts for target selection, and finally simulate SDSS/BOSS DR14 galaxy spectra. We compute photometric, astrometric and spectroscopic properties for red and blue, real and simulated galaxies, finding very good agreement. We compare the statistical properties of the samples by decomposing them with Principal Component Analysis (PCA). We find very good agreement for red galaxies and a good, but less pronounced one, for blue galaxies, as expected given the known difficulty of simulating those. Finally, we derive stellar population properties, mass-to-light ratios, ages and metallicities, for all samples, finding again very good agreement. This shows how this method can be used not only to forecast cosmology surveys, but it is also able to provide insights into studies of galaxy formation and evolution.
description: 28 pages, 10 figures, accepted for publication in JCAP
Assessing cloud chemistry and numerical solver techniques
Creators: name: Hudman, Rynda
name: Barth, Mary
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2000

Results are reported from the World Meteorological Organization's Fifth International Cloud Modeling Workshop, Case 5, Part 1. The purpose of this simulation was to check numerical solvers of the gas-aqueous chemical system and discuss the effect of cloud chemistry on the gas-phase species. Six models of assorted spatial and temporal scales employing various numerical solver techniques were limited to box models using updated Lelieveld and Cruizen (1991) initial conditions. The base simulation, a two-hour midday run, 30 minutes clear air, one-hour cloudy air, and 30 minutes clear air, found that models agree on major constituent concentrations such as ozone (O₃) varying by 1% between models. Minor constituent concentrations, such as formic acid (HCOOH), were highly variable, with a 50% discrepancy between models possibly due to aqueous phase diffusion. This case found cloud effects of -1 to -2% in O₃ concentrations and -20 to -43% in formaldehyde (CH₂pO), both agreeing with recent results of similar studies. Optional simulations included intermittent cloud, different chemistry mechanisms, and varying pH.
Economic Efficiency and Sustainable Agricultural Intensification Practices in Smallholder Maize Farming: Evidence from Ethiopia
Creators: name: Oumer, A.
name: Burton, M.
name: Oumer, A.
name: Burton, M.
Publisher: name: Unknown
Year: 2018
Subjects: Food Security and Poverty

description: Sustainable agricultural intensification practices (SAIPs) have been promoted to improve environmental services and farm productivity. However, whether implementations of SAIPs in isolation or in combinations increase economic efficiency of smallholder farmers is unclear. This study investigates the effects of SAIPs on costs and cost efficiency using stochastic frontier modelling techniques with an application to Ethiopian maize production. The econometric approaches account for heterogeneity across farms and heteroscedasticity in the variance of cost inefficiency. The results reveal that combinations of SAIPs appear to reduce cost and cost inefficiency variability but not when they are implemented in isolation. The average cost efficiency of the sample farms was about 80% indicating the presence of considerable room for improvement. Other factors that significantly change economic inefficiency are also discussed. Overall, the results demonstrate the relevance of exploiting synergistic effects of SAIPs in the wake of ever increasing cost of fertilizer, soil degradation and climate variability and enrich the discussion regarding the need to implement a portfolio of these practices rather than in isolation. Policies should support promotion of suites of SAIPs as packages and tackle factors hindering economic efficiency to enhance food security and incomes of smallholder farmers in developing countries. Key words: cost efficiency, sustainable agricultural intensification practices, soil degradation, climate variability, stochastic cost frontier, smallholder farmers, Ethiopia Acknowledgement : We gratefully acknowledge the Australian Government through Australian Centre for International Agricultural Research (ACIAR) for funding this research. Ethiopian Institute of Agricultural Research (EIAR) and the International Wheat and Maize Improvement Centre (CIMMYT) are acknowledged for access to raw data. The Ethiopian National Meteorological Agency (ENMA) is also greatly acknowledged for access to climate data. We thank farmers, supervisors, enumerators and other technical staff and researchers from various partner institutions who contributed to the data collection process. All remaining errors are ours.
Framework testing and analysis using Laplace's equation
Creators: name: Hill, Brandeis
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2000

The study of scientific parallel computing frameworks are important to the research at the National Center for Atmospheric Research since many of the problems revolve around fluid dynamics. By implementing Laplace's equation on the Kernel Lattice Parallelism and Portable Extensible Toolkit for Scientific computing frameworks, we see the scalability and efficiency of each framework. With each test, the inputs are the number of processors and the size of the matrix, which yields the Laplace equation solver and the total runtimes. The strengths and disadvantages of these frameworks also assist in discovering its usefulness to the National Center for Atmospheric Research. We must access how these frameworks perform across processors and their times of execution in order to estimate its performance with more complicated flow equations.
U.S. Imports of Fruits and Vegetables Under Plant Quarantine Regulations, Fiscal Year 1987
Creators: name: Pearrrow, Joan
name: Pearrrow, Joan
Publisher: name: Unknown
Year: 1990
Subjects: subject: Agricultural and Food Policy
subject: Crop Production/Industries
subject: International Relations/Trade
subject: U.S. imports
subject: fruits
subject: vegetables
subject: plant quarantine regulations

description: U.S. imports of most fruits and vegetables are subject to regulations administered by the Animal and Plant Health Inspection Service. This statistical report summarizes imports of over 200 commodities by country of origin and port of entry from October 1, 1986, through September 30, 1987.
California flood damage and the El Niño Southern Oscillation
Creators: name: Heard, Preston
name: Pielke, Roger
name: Barker, Harriet
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2000

Despite efforts to reduce vulnerability to flooding in California, flood damages have increased significantly in recent years. Previous work has shown that precipitation variability in California is strongly influenced by the El Niño-Southern Oscillation. This paper compares ENSO with statewide flood damage in California normalized to 1999-dollar values. Results suggest that there is no clear, consistent relationship between El Niño and flood damage in California and indicate that large flood damage is not limited to this warm phase of ENSO.
An Unbinned Goodness-of-Fit Test Based on the Random Walk
Creators: name: Kinoshita, K.
Publisher: name: arXiv
Year: 2003
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: We describe a test statistic for unbinned goodness-of-fit of data in one dimension. The statistic is based on the two-dimensional Random Walk. The rejection power of this test is explored both for simple and compound hypotheses and, for the examples explored, it is found to be comparable to that for the chisquare test. We discuss briefly how it may be possible to extend this test to multi-dimensional data.
description: Talk from PhyStat2003, Stanford, Ca, USA, September 2003, 5 pages, LaTeX, 4 eps figures. PSN MOCT002
Program Provisions for Program Crops: A Database for 1961-90
Creators: name: Green, Robert C.
name: Green, Robert C.
Publisher: name: Unknown
Year: 1990
Subjects: subject: Agricultural and Food Policy
subject: Crop Production/Industries
subject: Policy database
subject: crop support programs
subject: parity price
subject: support price
subject: target price
subject: nonrecourse loan program
subject: marketing quota
subject: acreage allotments
subject: base acres
subject: program acres
subject: acreage diversion program
subject: acreage set-aside program
subject: acreage reduction program
subject: farmer -owned reserve
subject: program crops
subject: corn
subject: sorghum
subject: barley
subject: oats
subject: wheat
subject: rice
subject: upland cotton
subject: extra -long staple cotton

description: This report opens with a look at legislation which provided the foundation for commodity support programs and highlights legislation which revised and supplemented the basic structure of these programs. However, the main body of this report is devoted to program provisions for 1961-90 crops of corn, sorghum, barley, oats, wheat, rice, upland cotton, and extra-long staple cotton which are presented in tables with extensive footnotes clarifying the program specifics.
Explaining support for a sovereign Quebec: A collective action frames approach
Creators: name: Piroth, Scott Randall
Publisher: name: American University
Year: 2023

description: This dissertation uses the concept of collective action frames to answer the question of why individuals support or oppose nationalist movements. Specifically, I examine the question of why some Quebecers supported a sovereign Quebec while other Quebecers preferred that Quebec remain part of Canada during the period from 1980 to 1995. My approach to collective action frames emphasizes the central position that values occupy in an individual's identity. Recognizing that people who belong to the same ethnic group will not necessarily have the same values helps to explain why nationalist movements often achieve only partial success in mobilizing members of an ethnic group to support nationalist goals. Using survey data, this dissertation explores the values, the perceptions of injustice, and the perceptions of agency of individual Quebecers and considers how these values and perceptions relate to support for sovereignty. Those Quebecers with more secular, more morally permissive, and more individualistic values tend to support sovereignty, and I argue that such Quebecers often view sovereignty as an opportunity for changing the status quo and creating a better society. Moreover, nationalism fulfills an important function that was largely filled by religion in the past---providing collective status for the group. In addition, this dissertation examines how both supporters and opponents of sovereignty have framed this issue in political discourse. I contend that the movement for sovereignty was remarkably successful in framing the debate in favorable terms during the period from 1980 to 1995. The issues of sovereignty and the constitution dominated Quebec's political debate. Most francophone Quebecers have embraced a Quebec-centered identity, and believe that Quebec should have special powers to protect its French culture and recognition as a distinct society in Canada's Constitution. Therefore, Canada's inability or unwillingness to provide Quebec with such powers and recognition is perceived as an injustice. Finally, most Quebecers seem to view sovereignty as a realistic option for Quebec.
The Specification, Estimation, and Simulation of a Small Global Macroeconomic Model
Creators: name: Malley, James R.
name: Malley, James R.
Publisher: name: Unknown
Year: 1990
Subjects: subject: Agricultural and Food Policy
subject: Forecasting
subject: macroeconomic model
subject: multipliers
subject: simulation

description: This report describes the structure and simulation properties of a small global macroeconomic model (SGM). Simulation experiments comparing SGM results with those of other world models suggest that SGM is a viable tool for macroeconomic policy analysis.
Expectile hidden Markov regression models for analyzing cryptocurrency returns
Creators: name: Foroni, Beatrice
name: Merlo, Luca
name: Petrella, Lea
Publisher: name: arXiv
Year: 2023
Subjects: subject: Applications (stat.AP)
subject: Risk Management (q-fin.RM)
subject: FOS: Computer and information sciences
subject: FOS: Economics and business

description: In this paper we develop a linear expectile hidden Markov model for the analysis of cryptocurrency time series in a risk management framework. The methodology proposed allows to focus on extreme returns and describe their temporal evolution by introducing in the model time-dependent coefficients evolving according to a latent discrete homogeneous Markov chain. As it is often used in the expectile literature, estimation of the model parameters is based on the asymmetric normal distribution. Maximum likelihood estimates are obtained via an Expectation-Maximization algorithm using efficient M-step update formulas for all parameters. We evaluate the introduced method with both artificial data under several experimental settings and real data investigating the relationship between daily Bitcoin returns and major world market indices.
Ingannevoli sono i fossili più di ogni cosa
Creators: Gloria Nobile
Publisher: name: Media Inaf
Year: 2021

Sulla superficie di Marte, che è stata temporaneamente abitabile quattro miliardi di anni fa, una serie di processi chimici potrebbe aver generato falsi fossili, simili a quelli che potrebbero esistere se il pianeta avesse mai ospitato forme di vita. Distinguerli è la nuova sfida dei suoi esploratori. Lo suggerisce uno studio, condotto da un team di astrobiologi delle università di Oxford ed Edimburgo. Tutti i dettagli su Journal of the Geological Society
Ordered Exponential and Its Features in Yang-Mills Effective Action
Creators: name: Ivanov, A. V.
name: Kharuk, N. V.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: In this paper we discuss some non-trivial relations for ordered exponentials on smooth Riemannian manifolds. As an example of application, we study a dependence of the four-dimensional quantum Yang-Mills effective action on the background filed and gauge transformations. Also, we formulate some open questions about a structure of divergences.
description: LaTeX, 13 pages
Strongly Enhanced Current Densities in Superconducting Coated Conductors of YBa2Cu3O7-x + BaZrO3
Creators: name: MacManus-Driscoll, J. L.
name: Foltyn, S. R.
name: Jia, Q. X.
name: Wang, H.
name: Serquis, A.
name: Civale, L.
name: Maiorov, B.
name: Hawley, M. E.
name: Maley, M. P.
name: Peterson, D. E.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: There are numerous potential applications for superconducting tapes, based on YBa2Cu3O7-x (YBCO) films coated onto metallic substrates. A long established goal of more than 15 years has been to understand the magnetic flux pinning mechanisms which allow films to maintain high current densities out to high magnetic fields. In fact, films carry 1-2 orders of magnitude higher current densities than any other form of the material. For this reason, the idea of further improving pinning has received little attention. Now that commercialisation of conductors is much closer, for both better performance and lower fabrication costs, an important goal is to achieve enhanced pinning in a practical way. In this work, we demonstrate a simple and industrially scaleable route which yields a 1.5 to 5-fold improvement in the in-field current densities of already-high-quality conductors.
Centris (Paracentris) fisheri Snelling 1974
Creators: name: Pedro, Diego De
name: Ceccarelli, Fadia Sara
name: Sagot, Philippe
name: López-Reyes, Eulogio
name: Mullins, Jessica L.
name: Mérida-Rivas, Jorge A.
name: Falcon-Brindis, Armando
name: Griswold, Terry
name: Ascher, John S.
name: Gardner, Joel
name: Ayala, Ricardo
name: Vides-Borrell, Eric
name: Vandame, Rémy
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Apidae
Centris
Centris fisheri

description: Centris (Paracentris) fisheri Snelling, 1974
Endemic
[Holotype: LACM; ♂ 8.04 km NW San Ignacio, Mulegé, Baja California Sur, Mexico; October 11, 1972]
Centris fisheri is another endemic species of the BCP. This species had been recorded in the Sarcocaulescent Shrubland in September 1981 and the Gulf Coast by the INHS (iDigBio 2023). We reviewed the holotype collected in the Vizcaíno Desert in October 1972 (LACM). The CARCIB team extended the known distribution to BC by collecting it in July 2017 from Valle de los Cirios in the Central Desert. See fig. 88.
description: Published as part of Pedro, Diego De, Ceccarelli, Fadia Sara, Sagot, Philippe, López-Reyes, Eulogio, Mullins, Jessica L., Mérida-Rivas, Jorge A., Falcon-Brindis, Armando, Griswold, Terry, Ascher, John S., Gardner, Joel, Ayala, Ricardo, Vides-Borrell, Eric & Vandame, Rémy, 2024, Revealing the Baja California Peninsula's Hidden Treasures: An Annotated checklist of the native bees (Hymenoptera: Apoidea: Anthophila), pp. 1-391 in Zootaxa 5522 (1) on page 148, DOI: 10.11646/zootaxa.5522.1.1, http://zenodo.org/record/13920532
Physiological search for quantum biological effects based on the Wigner-Yanase connection between coherence and uncertainty
Creators: name: Kominis, I. K.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Biological Physics (physics.bio-ph)
subject: Chemical Physics (physics.chem-ph)
subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: A fundamental concept of quantum physics, the Wigner Yanase information, is here used as a measure of quantum coherence in spin-dependent radical-pair reactions pertaining to biological magnetic sensing. This measure is connected to the uncertainty of the reaction yields, and further, to the statistics of a cellular receptor-ligand system used to biochemically convey magnetic-field changes. Measurable physiological quantities, such as the number of receptors and fluctuations in ligand concentration, are shown to reflect the introduced Wigner-Yanase measure of singlet-triplet coherence. We arrive at a quantum-biological uncertainty relation, connecting the product of a biological resource and a biological figure of merit with the Wigner-Yanase coherence. Our approach can serve a general search for quantum-coherent effects within cellular environments.
description: 11 pages, 3 figures
Coherent-cluster-state generation in networks of degenerate optical parametric oscillators
Creators: name: Zhou, Zheng-Yang
name: Gneiting, Clemens
name: You, J. Q.
name: Nori, Franco
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Cluster states are versatile quantum resources and an essential building block for measurement-based quantum computing. The possibility to generate cluster states in specific systems may thus serve as an indicator regarding if and to what extent these systems can be harnessed for quantum technologies and quantum information processing in particular. Here, we apply this analysis to networks of degenerate optical parametric oscillators (DOPOs), also called coherent Ising machines (CIMs). CIMs are distinguished by their highly flexible coupling capabilities, which makes it possible to use them, e.g., to emulate large spin systems. As CIMs typically operate with coherent states (and superpositions thereof), it is natural to consider cluster states formed by superpositions of coherent states, i.e., coherent cluster states. As we show, such coherent cluster states can, under ideal conditions, be generated in DOPO networks with the help of beam splitters and classical pumps. Our subsequent numerical analysis provides the minimum requirements for the generation of coherent cluster states under realistic conditions. Moreover, we discuss how nonequilibrium pumps can improve the generation of coherent cluster states. In order to assess the quality of the cluster-state generation, we map the generated states to an effective spin space using modular variables, which allows us to apply entanglement criteria tailored for spin-based cluster states.
description: 13 pages, 9 figures
1988 FARM COSTS AND RETURNS SURVEY DATA: SELECTED STATE AND REGION HIGHLIGHTS
Creators: name: , Agriculture
name: , Agriculture
Publisher: name: Unknown
Year: 1990
Subjects: subject: Agricultural and Food Policy
subject: Agricultural Finance
subject: Farm Costs and Returns Survey
subject: net cash farm income
subject: debt/asset ratio
subject: farm production expenditures

description: C-This publication is a collection of 34 reports highlighting 1988 data compiled from the annual Farm Costs and Returns Survey (FCRS). The State and regional level reports focus on financial characteristics of farms and farm operators from survey results. A farm's economic status is evaluated using the net cash income position and the ratio of debts to assets relationship. Regional production expenditures are compared by farm type. A brief discussion of farm characteristics by region are also presented.