cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
AN ANALYTICAL REVIEW AND SYNTHESIS OF PREFERRED RESEARCH METHODS IN THE MSU FOOD SECURITY PROJECT
Creators: name: Tefft, James F.
name: Tefft, James F.
Publisher: name: Unknown
Year: 1990
Subjects: Food Security and Poverty
Research Methods/ Statistical Methods

description: The purpose of this study was to review the design and implementation of food security research in Mali, Rwanda, Senegal, Somalia, Zimbabwe during the first and selected later phases of the Food Security in Africa Cooperative Agreement between Michigan State University and the U.S. Agency for International Development. This paper discusses principles and techniques for designing research, formulating questions and developing questionnaires, conducting the field work, and disseminating the findings. The primary objective was to learn from the experiences of prior researchers and to synthesize the research methods that this project has found to be effective and which may be useful to future researchers in the development and execution of policy-relevant field research.
A BMS-invariant free fermion model
Creators: name: Hao, Peng-Xiang
name: Song, Wei
name: Xiao, Zehua
name: Xie, Xianjin
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We used the Cartan formalism to construct fermionic models that are compatible with Galilean or Carrollian symmetry and rigid scaling symmetry. The free Carrollian fermion model exhibits conformal Carrollian symmetry which is isomorphic to the asymptotic symmetries for flat spacetime in three dimensions, namely the BMS$_3$ symmetry. We performed canonical quantization to this free BMS fermion model, discussed both the highest weight vacuum and the induced vacuum, calculated the correlation functions and the torus partition function. Finally we constructed $\mathcal N=2$ supersymmetric theories by combining the free fermion model and the free scalar model.
description: 66 pages;v2, minor revision: typos correted and some statement rephrased
Lasing from a circular Bragg nanocavity with an ultra-small modal volume
Creators: name: Scheuer, Jacob
name: Green, William M. J.
name: DeRose, Guy A.
name: Yariv, Amnon
Publisher: name: arXiv
Year: 2005
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We demonstrate single-mode lasing at telecommunication wavelengths from a circular nanocavity employing a radial Bragg reflector. Ultra-small modal volume and Sub milliwatt pump threshold level are observed for lasers with InGaAsP quantum well active membrane. The electromagnetic field is shown to be tightly confined within the 300nm central pillar of the cavity. The quality factors of the resonator modal fields are estimated to be on the order of a few thousands.
description: 3 pages, 4 figures Submitted to APL
Correlation engineering via non-local dissipation
Creators: name: Seetharam, Kushal
name: Lerose, Alessio
name: Fazio, Rosario
name: Marino, Jamir
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Controlling the spread of correlations in quantum many-body systems is a key challenge at the heart of quantum science and technology. Correlations are usually destroyed by dissipation arising from coupling between a system and its environment. Here, we show that dissipation can instead be used to engineer a wide variety of spatio-temporal correlation profiles in an easily tunable manner. We describe how dissipation with any translationally-invariant spatial profile can be realized in cold atoms trapped in an optical cavity. A uniform external field and the choice of spatial profile can be used to design when and how dissipation creates or destroys correlations. We demonstrate this control by preferentially generating entanglement at a desired wavevector. We thus establish non-local dissipation as a new route towards engineering the far-from-equilibrium dynamics of quantum information, with potential applications in quantum metrology, state preparation, and transport.
description: 6+10 pages, 4+2 figures
AGRICULTURAL RESEARCH IN TANZANIA
Creators: name: Chota, Evelyne
name: Chota, Evelyne
Publisher: name: Unknown
Year: 1986
Subjects: Research and Development/Tech Change/Emerging Technologies

description: Over the years the Government of Tanzania has recognized the need for modern technology to increase agricultural production. Since the colonial period, agricultural research institutions have been established to cover most of the ecological zones of the country and research had been carried out on major crops by these institutes. However, recently critics have raised the question as to whether this research has been consistent with the needs of the majority of farmers. Closely related to this is the question of how effective the research findings have been communicated to the farmers. These questions have been raised due to the persistently low agricultural productivity and the use of traditional methods of farming, despite all the research that has been done in the country. This paper focuses on agricultural research in Tanzania. Its intention is to suggest ideas for further investigation into how to increase the effectiveness of the research system. This paper describes the evolution and major constraints faced in conducting agricultural research in Tanzania. The specific objectives of the study are to: 1) Identify the major constraints to agricultural research; 2) Examine the potential for the application of the Farming Systems Research approach; 3) Determine some of the analytical issues to be considered in agricultural research; and 4) Identify relevant analytical models to assess new technology for small farmers.
ANALYSIS OF THE ZATPID I RURAL HOUSEHOLD SURVEY: WITH EMPHASIS ON DATA QUALITY AND A COMPARISON OF CHARACTERISTICS OF SMALLHOLDER MAIZE PRODUCERS OF ZAMBIA
Creators: name: Sumbye, A. Kapena
name: Sumbye, A. Kapena
Publisher: name: Unknown
Year: 1989
Subjects: Consumer/Household Economics
Crop Production/Industries

description: Between December 1984 and July 1986, the Planning Division of the Ministry of Agriculture and Water Development, in conjunction with the Rural Development Studies Bureau of the University of Zambia and Iowa State University conducted a rural household survey. This is referred to as the ZATPID I Rural Household Survey, because it was conducted during phase I of ZATPID, a five year USAID/Zambia project. ZATPID stands for Zambia Agricultural Training, Planning and Institutional Developmental Project. The aim of the survey was to provide data for use in analysis to inform policy making in Zambia. It was also supposed to provide a data bank for use by Zambian graduate students to meet the research requirements of their degree programs. The objectives of the study are: 1) to review the methods and survey procedures used in the RHS; 2) to complete internal and logical consistency checks on the data base resulting from the 477 households surveyed in the flow portion of the RHS in order to identify the number of likely cases of valid information; 3) to select a subsample of households producing maize and to conduct a comparison of selected smallholder maize production characteristics; and 4) to discuss the implications of the findings of both the consistency checks and the comparative analysis, and to recommend further cleaning and/or analysis of the data set.
Effective local geometric quantities in fuzzy spaces from heat kernel expansions
Creators: name: Sasakura, Naoki
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The heat kernel expansion can be used as a tool to obtain the effective geometric quantities in fuzzy spaces. Generalizing the efficient method presented in the previous work on the global quantities, it is applied to the effective local geometric quantities in compact fuzzy spaces. Some simple fuzzy spaces corresponding to singular spaces in continuum theory are studied as specific examples. A fuzzy space with a non-associative algebra is also studied.
description: Two references added, typos, 26 pages, many figures, LaTeX
Negotiating parenting and places of care in Vancouver, BC
Creators: name: Bester, Trina Louise
Publisher: name: University of British Columbia
Year: 2009

description: The home as a site for childcare is linked to notions of 'good' parenting, and the employment of a nanny is often meant to create an extended family which enables a child to be nurtured in this private space. Qualitative interviews undertaken with fifty-one families and eleven nannies indicate that this childcare arrangement is complex and involves shifting and divergent constructions of what good parenting and good childcare are. This childcare arrangement often failed because of the complexities of the employer-employee relationship, and a failed attempt at familial attachment. A partial explanation as to why this fails is that some nannies view their employment as a 'bad' parenting strategy, and suggest that it is the parents who should be nurturing the children. This tension around the appropriateness of certain childcare strategies is indicative of discourses of proper parenting and maternal ideals, and is intimately connected to place. Expanding on this theme, interviews were undertaken with ten daycares in the city of Vancouver to examine how discourses of proper parenting are reworked in a 'public' space. This inquiry introduces more directly issues of class, opportunity and the socialization of children. The maternal ideals expressed in the first part of the study are reworked, and sometimes abandoned, in the delivery of public childcare services. Further, there is a process of normalization that takes place in the designation and segregation of children based on age, and whether they are 'typical' or 'special needs'. I argue that greater attention to emotion is needed in the study of childcare, and greater appreciation of difference is needed in the delivery of childcare. This thesis also questions its original premise, that of looking at childcare as public and private options, and of seeing childcare as an employment strategy.
title: Le avventure di Terrix - Missione Sustainabilia
Creators: name: Leone, Chiara
Publisher: name: University of Bologna
Year: 2023

description: Terrix, il supereroe di FoodE, deve salvare la città di Sustainabilia. Avrà bisogno dell'aiuto di tutti i suoi amici, i supereroi e le supereroine di FoodE, disegnati dagli alunni e dalle alunne delle scuole elementari di Bologna.
On the relationship between Type Ia supernova luminosity and host-galaxy properties
Creators: name: Murakami, Yukei S.
name: Stahl, Benjamin E.
name: Zhang, Keto D.
name: Chu, Matthew R.
name: McGinness, Emma C.
name: Patra, Kishore C.
name: Filippenko, Alexei V.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: A string of recent studies has debated the exact form and physical origin of an evolutionary trend between the peak luminosity of Type Ia supernovae (SNe Ia) and the properties of the galaxies that host them. We shed new light on the discussion by presenting an analysis of ~200 low-redshift SNe Ia in which we measure the separation of Hubble residuals (HR; as probes of luminosity) between two host-galaxy morphological types. We show that this separation can test the predictions made by recently proposed models, using an independently and empirically determined distribution of each morphological type in host-property space. Our results are partially consistent with the new HR--age slope, but we find significant scatter in the predictions from different galaxy catalogues. The inconsistency in age illuminates an issue in the current debate that was not obvious in the long-discussed mass models: HR--host-property models are strongly dependent on the methods employed to determine galaxy properties. While our results demonstrate the difficulty in constructing a universal model for age as a proxy for host environment, our results indeed identify evolutionary trends between mass, age, morphology, and HR values, encouraging (or requiring, if such trends are to be accounted for in cosmological studies) further investigation.
description: 5 pages, 3 figures. Accepted to MNRAS
Effects of task-irrelevant whispered speech on short-term memory
Creators: name: Kattner, Florian
name: Stokar von Neuforn, Cosima M. A.
name: Scholz, Patrizia F.
name: Downing, Lia
name: Föcker, Julia
Publisher: name: Zenodo
Year: 2024

description: Irrelevant background speech is known to disrupt cognitive performance either by interfering with specific processes (e.g., serial rehearsal) or through attentional capture. Here, two experiments are presented to test the disruptive effect of whispered background speech in a serial recall task. According to an interference-by-process account, whispered speech should be less disruptive due to its reduced amplitude modulations and temporal fine structure compared to loud speech, thus providing weaker order cues to the auditory system and inducing less interference with seriation processes. However, due to the enhanced listening effort to process whispered speech (when presented in a comprehensible language), it could be argued that additional attentional resources will be demanded thus producing more disruption of serial recall. In Experiment 1, to-be-remembered letters were presented visually on the screen while either voiced or whispered to-be-ignored speech was presented via headphones. Half of the speech trials contained only a single German word that was played repeatedly (steady-state), whereas the other trials contained a full German sentence. Memory accuracy was significantly lower in the presence of sentential speech compared to steady-state words, indicating interference-by-process. More importantly, whispered speech produced more disruption compared to loud speech, indicating an additive effect of attentional capture potentially due to enhanced listening effort required to process semantic information. To test specifically whether the disruptive effect of whispered speech was due to enhanced listening effort, the same German speech materials were presented to a sample of English participants who did not speak or understand German in Experiment 2. It was found that in this case whispered speech was less disruptive than loud speech, indicating that psychoacoustic speech properties may dominate when no listening effort is demanded as in case of an incomprehensible language.
The Strangeness Physics Program at CLAS
Creators: name: Carman, D. S.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: An extensive program of strange particle production off the proton is currently underway with the CEBAF Large Acceptance Spectrometer (CLAS) in Hall B at Jefferson Laboratory. This talk will emphasize strangeness photo- and electroproduction in the baryon resonance region between W =1.6 and 2.5 GeV, where indications of s-channel structure are suggestive of high-mass baryon resonances coupling to kaons and hyperons in the final state. Precision measurements of cross sections and polarization observables are being carried out with both electron and real photon beams, both of which are available with high polarization at energies up to 6 GeV.
description: 10 pages, 6 figures, N*2005 Conference
GOAT PRODUCTION IN RWANDA: ASSESSING THE POTENTIAL FOR FUTURE DEVELOPMENT
Creators: name: Rwamasirabo, Serge
name: Rwamasirabo, Serge
Publisher: name: Unknown
Year: 1990
Subjects: Livestock Production/Industries

description: This study is uniquely structured to assess the potential for future development of the Rwandan goat industry based on a thorough empirical analysis of how farm households of many different types participate in, and depend on, this pervasive industry. Data from the 1984 National Agricultural Survey in Rwanda and the 1989 follow-on survey permit us to highlight recent trends in goat (and other livestock) production in Rwanda, and to assess the degree to which variations in goat production are linked to other household and farm characteristics. Findings show that farmers are adapting to population pressure by shifting away from the production of cattle in favor of small ruminant production. Declining farm size, low start-up costs and relatively low mortality rates have all contributed to the growth of goat production, particularly among young farmers and those with small holdings. The major factors influencing livestock production in Rwanda are farm size and the availability of household labor. Rwandan farmers are currently overstocked with livestock, marketing only one-third of the goats potentially available for sale each year. This is partly because meat consumption in Rwanda is very low due to its high cost relative to other sources of protein, but also because farmers use livestock as a mechanism for savings and the accumulation of wealth, to be "cashed in" only for special occasions or in times of need. Possibilities for local processing of hides and skins and for manufacturing leather products are reviewed.
Deepfake Detection: A Comprehensive Survey from the Reliability Perspective
Creators: name: Wang, Tianyi
name: Liao, Xin
name: Chow, Kam Pui
name: Lin, Xiaodong
name: Wang, Yinglong
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Multimedia (cs.MM)
subject: FOS: Computer and information sciences

description: The mushroomed Deepfake synthetic materials circulated on the internet have raised a profound social impact on politicians, celebrities, and individuals worldwide. In this survey, we provide a thorough review of the existing Deepfake detection studies from the reliability perspective. We identify three reliability-oriented research challenges in the current Deepfake detection domain: transferability, interpretability, and robustness. Moreover, while solutions have been frequently addressed regarding the three challenges, the general reliability of a detection model has been barely considered, leading to the lack of reliable evidence in real-life usages and even for prosecutions on Deepfake-related cases in court. We, therefore, introduce a model reliability study metric using statistical random sampling knowledge and the publicly available benchmark datasets to review the reliability of the existing detection models on arbitrary Deepfake candidate suspects. Case studies are further executed to justify the real-life Deepfake cases including different groups of victims with the help of the reliably qualified detection models as reviewed in this survey. Reviews and experiments on the existing approaches provide informative discussions and future research directions for Deepfake detection.
description: Accepted to ACM Computing Surveys
The original Wigner's friend paradox within a realist toy model
Creators: name: Lostaglio, Matteo
name: Bowles, Joseph
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The original Wigner's friend paradox is a gedankenexperiment involving an observer described by an external agent. The paradox highlights the tension between unitary evolution and collapse in quantum theory, and is sometimes taken as requiring a reassessment of the notion of objective reality. In this note however we present a classical toy model in which (i) The contradicting predictions at the heart of the thought experiment are reproduced (ii) Every system is in a well-defined state at all times. The toy model shows how puzzles such as Wigner's friend's experience of being in a superposition, conflicts between different agents' descriptions of the experiment, the positioning of the Heisenberg's cut and the apparent lack of objectivity of measurement outcomes can be explained within a classical model where there exists an objective state of affairs about every physical system at all times. Within the model, the debate surrounding the original Wigner's friend thought experiment and its resolution have striking similarities with arguments concerning the nature of the second law of thermodynamics. The same conclusion however does not apply to more recent extensions of the gedankenexperiment featuring multiple encapsulated observers, and shows that such extensions are indeed necessary avoid simple classical explanations.
description: 7 pages, 1 figure. Close to published version
Competing imperatives : individual rights and international obligations in extradition from Canada to the U.S.A.
Creators: name: Botting, Gary
Publisher: name: University of British Columbia
Year: 2009

description: Contemporary developments in extradition law culminating in the new Extradition Act mirror equally intriguing historical developments in Canada-U.S. extradition law and practice. This thesis examines the process by which each country approached extradition and treaty negotiation, historically and politically, treaty by treaty. It notes the ways in which extradition limped along in times when there was no treaty. It examines the historical background of, and the substantial body of law arising from, the three main treaties that have dealt with extradition between the United States and what is now Canada - the Jay Treaty (1794), the Ashburton-Webster Treaty (1842), and the current Canada-U.S. Treaty (1971). It analyses the legislation which establishes the procedure to be used in extradition cases in Canada, including the new Extradition Act, which received royal assent on 17 June 1999. It looks at the ways in which treaties and legislation have been applied by the courts and by the executive branch of successive governments. It explores and analyses the positions that the courts in Canada have taken with respect to the conflict between individual rights and international obligations. It examines the new Act in the context of relevant case law with a view to anticipating the ways in which it is likely to impact on Canada's extradition policy in the future. Finally, it suggests that in order to preserve individual rights and protections over perceived international obligations, the judiciary will have to take or be granted powers of discretion that are equal to or greater than those enjoyed by the Minister of Justice.
A Study of Checkpointing in Large Scale Training of Deep Neural Networks
Creators: name: Rojas, Elvis
name: Kahira, Albert Njoroge
name: Meneses, Esteban
name: Gomez, Leonardo Bautista
name: Badia, Rosa M
Publisher: name: arXiv
Year: 2020
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: Deep learning (DL) applications are increasingly being deployed on HPC systems, to leverage the massive parallelism and computing power of those systems for DL model training. While significant effort has been put to facilitate distributed training by DL frameworks, fault tolerance has been largely ignored. In this work, we evaluate checkpoint-restart, a common fault tolerance technique in HPC workloads. We perform experiments with three state-of-the-art DL frameworks common in HPC Chainer, PyTorch, and TensorFlow). We evaluate the computational cost of checkpointing, file formats and file sizes, the impact of scale, and deterministic checkpointing. Our evaluation shows some critical differences in checkpoint mechanisms and exposes several bottlenecks in existing checkpointing implementations. We provide discussion points that can aid users in selecting a fault-tolerant framework to use in HPC. We also provide takeaway points that framework developers can use to facilitate better checkpointing of DL workloads in HPC.
Co-formation of the thin and thick discs revealed by APOGEE-DR16 and Gaia-DR2
Creators: name: Silva, Leandro Beraldo e
name: Debattista, Victor P.
name: Nidever, David
name: Amarante, João A. S.
name: Garver, Bethany
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Since thin disc stars are younger than thick disc stars on average, the thin disc is predicted by some models to start forming after the thick disc had formed, around 10 Gyr ago. Accordingly, no significant old thin disc population should exist. Using 6-D coordinates from Gaia-DR2 and age estimates from Sanders & Das (2018), we select $\sim 24000$ old stars (${τ> 10}$ Gyr, with uncertainties $\lesssim 15\%$) within 2 kpc from the Sun (full sample). A cross-match with APOGEE-DR16 ($\sim 1000$ stars) reveals comparable fractions of old chemically defined thin/thick disc stars. We show that the full sample pericenter radius ($r_\mathrm{per}$) distribution has three peaks, one associated with the stellar halo and the other two having contributions from the thin/thick discs. Using a high-resolution $N$-body+Smooth Particle Hydrodynamics simulation, we demonstrate that one peak, at $r_\mathrm{per}\approx 7.1$ kpc, is produced by stars from both discs which were born in the inner Galaxy and migrated to the Solar Neighbourhood. In the Solar Neighbourhood, $\sim 1/2$ ($\sim 1/3$) of the old thin (thick) disc stars are classified as migrators. Our results suggest that thin/thick discs are affected differently by radial migration inasmuch as they have different eccentricity distributions, regardless of vertical scale heights. We interpret the existence of a significant old thin disc population as evidence for an early co-formation of thin/thick discs, arguing that clump instabilities in the early disc offer a compelling explanation for the observed trends.
description: 12+2 pages, 10 figures, minor changes to match published version
A cosmological model with complex scalar field
Creators: name: Zhai, Xiang-hua
name: Zhao, Yi-bin
Publisher: name: arXiv
Year: 2005
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper, we wish to point out the possibility of using a complex scalar field to account for the inflationary stage and the current acceleration. By the analysis of the dynamical system and numerical work, we show that the amplitude of the complex scalar field plays the role of the inflaton whereas the phase is the quintessence field. The numerical solutions describe heteroclinic orbits, which interpolate between an unstable critical point and a late-time de Sitter attractor. Therefore, this model is more natural to explain the two stages of acceleration.
description: 7 pages, 2 figure
An auditory loudness model with hearing loss
Creators: name: Bramsløw, Lars
Publisher: name: Eriksholm Research Centre
Year: 2024

description: The ‘AUDMOD’ model presented here models masking patterns, specific loudness, and total loudness for any stimulus and hearing loss, as specified by a standard audiogram. It is a strictly perceptual / behavioural model, based on the Moore & Glasberg roex-filter model, combined with the Zwicker & Fastl loudness model. The auditory filter bandwidth depends on both signal level and hearing loss, both leading to increased upward spread of masking. The computational requirements are very low, making the model suitable for deep learning applications, including closed-loop hearing loss compensation. Furthermore, the model can be applied in a straightforward manner for analysis and interpretation of hearing aid functionality.
Non-monotonic Rheology and Stress Heterogeneity in confined Granular suspensions
Creators: name: Hu, Haitao
name: Zhao, Yiqiu
name: Zhao, Weiwei
name: Qiao, Ligen
name: Xu, Qin
Publisher: name: arXiv
Year: 2022
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We systematically investigated the impact of boundary confinement on the shear-thickening rheology of dense granular suspensions. Under highly confined conditions, dense suspensions were found to exhibit size-dependent or even rarely reported non-monotonic ($S$-shaped) flow curves in steady states. By performing in-situ boundary stress microscopy measurements, we observed enhanced flow heterogeneities in confined suspensions, where concentrated high-stress domains propagated stably either along or against the shear direction. By comparing the boundary stress microscopy results with macroscopic flow responses, we revealed the connection between non-monotonic rheology and stress heterogeneity in confined suspensions. These findings suggest the possibility of controlling suspension rheology by imposing different boundary confinements.
An Economic Assessment of the BSE Crisis in Canada: Impact of Border Closure and BSE Recovery Programs
Creators: name: Weerahewa, Jeevika
name: Meilke, Karl D.
name: Le Roy, Danny G.
name: Weerahewa, Jeevika
name: Meilke, Karl D.
name: Le Roy, Danny G.
Publisher: name: Unknown
Year: 2008
Subjects: subject: International Relations/Trade
subject: Livestock Production/Industries
subject: BSE
subject: cattle and beef
subject: partial equilibrium model
subject: simulation
subject: trade ban

description: This article assesses the economic consequences of three alternative government responses to the BSE crisis in Canada: 1) expansion in slaughter capacity; 2) partial destruction of the cattle herd; and 3) deficiency payments. Each of these policies is evaluated under four different border situations: 1) autarky; 2) free trade in young beef only; 3) free trade in young beef and cattle; and 4) complete free trade. The results of the policy analysis are quite sensitive to the border assumptions, making it impossible to select a “best” policy without perfect foresight with respect to the timing and the extent of the border opening.
Explaining the Many Threshold Structures in the Heavy-Quark Hadron Spectrum
Creators: name: Dong, Xiang-Kun
name: Guo, Feng-Kun
name: Zou, Bing-Song
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Lattice (hep-lat)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Tremendous progress has been made experimentally in the hadron spectrum containing heavy quarks in the last two decades. It is surprising that many resonant structures are around thresholds of a pair of heavy hadrons. There should be a threshold cusp at any $S$-wave threshold. By constructing a nonrelativistic effective field theory with open channels, we discuss the generalities of threshold behavior, and offer an explanation of the abundance of near-threshold peaks in the heavy quarkonium regime. We show that the threshold cusp can show up as a peak only for channels with attractive interaction, and the width of the cusp is inversely proportional to the reduced mass relevant for the threshold. We argue that there should be threshold structures at any threshold of a pair of heavy-quark and heavy-antiquark hadrons, which have attractive interaction at threshold, in the invariant mass distribution of a heavy quarkonium and light hadrons that couple to that open-flavor hadron pair. The structure becomes more pronounced if there is a near-threshold pole. Predictions of the possible pairs are also given for the ground state heavy hadrons. Precisely measuring the threshold structures will play an important role in revealing the heavy-hadron interactions, and thus understanding the puzzling hidden-charm and hidden-bottom structures.
description: Title changed, version to appear in Phys. Rev. Lett.; 8 pages, 2 figures
An Economic Evaluation of Conservation Farming Practices for the Central West of NSW
Creators: name: Farrell, Terence C.
name: Farrell, Terence C.
Publisher: name: Unknown
Year: 2008
Subjects: subject: Environmental Economics and Policy
subject: Farm Management
subject: No-till
subject: conservation
subject: farming
subject: tillage
subject: cropping systems

description: Economic benefits that arise from conservation farming practices need to be assessed over several years to account for improvements in soil structure and nutrient levels. A gross margin model was used to assess benefits over the eight-year period 1999-2006 for 12 regions in the central west of NSW. The annual benefits from improved soil structure ranged from $2.46 to $12.82 per hectare (ha). A reduction in tractor power produced annual savings in the range of $0.60 to $4.05 per ha. The cost of soil compaction by livestock grazing on crop areas ranged from $3.41 to $14.90 per ha. The break-even time to pay back costs for the conversion of machinery for no-till seeding was two to three seasons.
"An anti-national disorder" : Antonio Canales and northeastern Mexico, 1836-1852
Creators: name: Ridout, Joseph Benjamin, 1969-
Publisher: name: The University of Texas at Austin
Year: 1994
Subjects: subject: Mexico
subject: Politics and government
subject: History
subject: Regionalism
subject: Antonio Canales
subject: 19th century
subject: Territories and possessions
subject: Mexico--Politics and government--1821-1861
subject: Regionalism--Mexico--History--19th century
subject: Canales, Antonio, 1800?-1852?
subject: Mexico--Territories and possessions--History--19th century

description: This study explores regionalism in northeastern Mexico from 1836 to 1852. During the years of the early Republic, Tamaulipas and its neighboring departments sought to resist control by the central government and preserve local autonomy. This program culminated in a separatist revolt from 1838 to 1840 known as the "Republic of the Rio Grande," which proposed that a confederation of northeastern states secede from Mexico and ally with Texas. Antonio Canales, a cacique from the northreastern Mexican frontier who led the uprising, exemplified many of the ambivalent attitudes in the northeast toward the Mexico City administration during this period. Seeking to protect the interests of the northeastern frontier, Canales, at one time, headed the "Rio Grande" separatist revolt, and, later, led the guerrilla resistance to the United States' invasion of the northeast (1846-48). The experience of invasion augured a new era in the northeast, in which the idea of parochial separatism was abandoned, and a greater sense of national identity took hold
Magnetic properties in a partially oxidized nanocomposite of Cu-CuCl
Creators: name: Li, Qi
name: Zhang, Shi-Wei
name: Zhang, Yan
name: Chen, Chinping
Publisher: name: arXiv
Year: 2005
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Magnetism of a very thin antiferromagnetic (AFM) surface CuO has been investigated with the partially oxidized nanocomposites of Cu-CuCl, ~ 200 nm. The samples are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, X-ray-excited Auger electron spectroscopy, transmission electron microscope and magnetic measurements. The characterizations indicate that the composites have a core-shell structure. Before the oxidation, it is (Cu)core/(CuCl)shell, and after the oxidation, (Cu)core/(Cu2O+CuCl+minuteCuO)shell. The magnetic measurements have revealed that a ferromagnetic (FM) like open hysteresis exists at the temperature below the freezing point, TF. In the high field region, a paramagnetic (PM) response appears without showing a sign of saturation. Also, the field dependent magnetization (M-H) measurement is PM-like at T > TF. These interesting magnetic properties are evident to arise from the AFM CuO on the outer surface. They are attributed to the uncompensated surface spins of Cu2+ and the effect of surface random potential. More interestingly, the magnetic susceptibility is greatly enhanced in the presence of Cl- anions at T < TF, according to the field-cooled/zero-field-cooled (FC/ZFC) measurements. This further supports the point that the disorder or frustration effect of the impurity would reduce the AFM ordering of CuO and increase the level of uncompensated spins.
description: 8 pages including 7 figures, Nanotechnology In Press
2-Ruled Hypersurfaces in a Walker 4-Manifold
Creators: name: Dramé, Mohamed Ayatola
name: Ndiaye, Ameth
name: Diallo, Abdoul Salam
Publisher: name: arXiv
Year: 2022
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: The hypersurface is one of the most important objects in a space. Many authors studied diffrent geometric aspects of hypersurfaces in a space. In this paper, we define three types of 2-ruled hypersurfaces in a Walker 4-manfold E 41 . We obtain the Gaussian and mean curvatures of the 2-ruled hypersurfaces of type-1, type-2 and type 3. We give some characterizations about its minimality. We also deal with the first Laplace-Beltrami operators of these types of 2-ruled hypersurfaces in the considered Walker 4-manifold.
description: arXiv admin note: substantial text overlap with arXiv:2205.10808
Defining Access to Health Care: Evidence on the Importance of Quality and Distance in Rural Tanzania
Creators: name: Klemick, Heather
name: Leonard, Kenneth L.
name: Masatu, Melkiory C.
name: Klemick, Heather
name: Leonard, Kenneth L.
name: Masatu, Melkiory C.
Publisher: name: Unknown
Year: 2008
Subjects: Community/Rural/Urban Development
Health Economics and Policy

description: We examine the implications of health seeking behavior on access to quality health care using a unique dataset that combines a household survey from rural Tanzania with the location and quality of all health facilities available to households. Patients do not always visit the nearest facility, but choose from among multiple facilities, improving the quality of care they receive by bypassing low quality facilities. Recognizing this behavior alters the projected benefits to health interventions, reducing the value of focusing on the staff qualifications and increasing the value of focusing on travel time and the motivation of current staff.
Universal features of electron-phonon interactions in atomic wires
Creators: name: de la Vega, L.
name: Martin-Rodero, A.
name: Agrait, N.
name: Yeyati, A. Levy
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The effect of electron-phonon interactions in the conductance through metallic atomic wires is theoretically analyzed. The proposed model allows to consider an atomic size region electrically and mechanically coupled to bulk electrodes. We show that under rather general conditions the features due to electron-phonon coupling are described by universal functions of the system transmission coefficients. It is predicted that the reduction of the conductance due to electron-phonon coupling which is observed close to perfect transmission should evolve into an enhancement at low transmission. This crossover can be understood in a transparent way as arising from the competition between elastic and inelastic processes.
description: 5 pages, 5 figures
Sociodemographic disparities and potential biases in persistent pain estimates: findings from 5 waves of the Irish longitudinal study on ageing (TILDA)
Creators: name: Ryan, Eva
name: HANNIGAN, AILISH
name: Grol-Prkopczyk, H.
name: May, P.
name: PURTILL, HELEN
Publisher: name: University of Limerick
Year: 2024
Subjects: classificationCode: 420309
subject: Health management

description: Background: Pain is a prevalent, debilitating condition among older adults. Much evidence on this topic comes from cohort studies, which may be affected by attrition and measurement bias. Little is known about the impact of these biases on pain estimates for European older adults. Additionally, there is a lack of longitudinal research on pain and sociodemographic disparities in Irish older adults. Methods: We analysed data from 8171 participants (aged ≥50 at baseline) across five waves of the Irish Longitudinal Study on Ageing. Longitudinal pain severity and sociodemographic disparities in pain were explored visually and using a latent growth curve model. Using multivariate logistic regression, we examined bias due to attrition at later waves associated with reported pain at Wave 1. Measurement biases due to reporting heterogeneity were assessed by investigating associations between sociodemographic factors and pain-related disability for given pain levels. Results: Wave 1 severe pain was associated with increased odds of attrition due to death by Wave 5 (AOR: 1.63, 95% CI: 1.20, 2.19). Not having private health insurance was associated with increased odds of pain-related disability at Wave 1, controlling for pain severity (AOR: 1.37, 95% CI: 1.15, 1.64). These results suggested mortality bias and reporting heterogeneity measurement bias, respectively. Sex, education level, and private health insurance status disparities in pain were observed longitudinally. Conclusions: Mortality bias and reporting heterogeneity measurement bias must be accounted for to improve older adult pain estimates. There is a need for policymakers to address sociodemographic disparities in older adult pain levels. Significance: This study highlights a need to address bias in the estimation of pain in observational studies of older adults. Understanding the sources and extent of these biases is important so that health practices and policies to address pain disparities can be guided by accurate estimates. Women, those with lower educational attainment, and those without private health insurance were found to have the highest pain burden longitudinally, suggesting a need for targeted interventions for these groups in Ireland and internationally
Conditional probabilities via line arrangements and point configurations
Creators: name: Clarke, Oliver
name: Mohammadi, Fatemeh
name: Motwani, Harshit J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Commutative Algebra (math.AC)
subject: Algebraic Geometry (math.AG)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 13P25 (Primary) 14N20, 62H99, 62E10 (Secondary)

description: We study the connection between probability distributions satisfying certain conditional independence (CI) constraints, and point and line arrangements in incidence geometry. To a family of CI statements, we associate a polynomial ideal whose algebraic invariants are encoded in a hypergraph. The primary decompositions of these ideals give a characterisation of the distributions satisfying the original CI statements. Classically, these ideals are generated by 2-minors of a matrix of variables, however, in the presence of hidden variables, they contain higher degree minors. This leads to the study of the structure of determinantal hypergraph ideals whose decompositions can be understood in terms of point and line configurations in the projective space.
description: 24 pages, 5 figures
Toeplitz determinants with a one-cut regular potential and Fisher--Hartwig singularities I. Equilibrium measure supported on the unit circle
Creators: name: Blackstone, Elliot
name: Charlier, Christophe
name: Lenells, Jonatan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Probability (math.PR)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We consider Toeplitz determinants whose symbol has: (i) a one-cut regular potential $V$, (ii) Fisher--Hartwig singularities, and (iii) a smooth function in the background. The potential $V$ is associated with an equilibrium measure that is assumed to be supported on the whole unit circle. For constant potentials $V$, the equilibrium measure is the uniform measure on the unit circle and our formulas reduce to well-known results for Toeplitz determinants with Fisher--Hartwig singularities. For non-constant $V$, our results appear to be new even in the case of no Fisher--Hartwig singularities. As applications of our results, we derive various statistical properties of a determinantal point process which generalizes the circular unitary ensemble.
description: 34 pages, 3 figures
Natural Evolutionary Strategies for Variational Quantum Computation
Creators: name: Anand, Abhinav
name: Degroote, Matthias
name: Aspuru-Guzik, Alán
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Machine Learning (cs.LG)
subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Natural evolutionary strategies (NES) are a family of gradient-free black-box optimization algorithms. This study illustrates their use for the optimization of randomly-initialized parametrized quantum circuits (PQCs) in the region of vanishing gradients. We show that using the NES gradient estimator the exponential decrease in variance can be alleviated. We implement two specific approaches, the exponential and separable natural evolutionary strategies, for parameter optimization of PQCs and compare them against standard gradient descent. We apply them to two different problems of ground state energy estimation using variational quantum eigensolver (VQE) and state preparation with circuits of varying depth and length. We also introduce batch optimization for circuits with larger depth to extend the use of evolutionary strategies to a larger number of parameters. We achieve accuracy comparable to state-of-the-art optimization techniques in all the above cases with a lower number of circuit evaluations. Our empirical results indicate that one can use NES as a hybrid tool in tandem with other gradient-based methods for optimization of deep quantum circuits in regions with vanishing gradients.
Two-dimensional scaling properties of experimental fracture surfaces
Creators: name: Ponson, Laurent
name: Bonamy, Daniel
name: Bouchaud, Elisabeth
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The morphology of fracture surfaces encodes the various complex damage and fracture processes occurring at the microstructure scale that have lead to the failure of a given heterogeneous material. Understanding how to decipher this morphology is therefore of fundamental interest. This has been extensively investigated over these two last decades. It has been established that 1D profiles of these fracture surfaces exhibit properties of scaling invariance. In this paper, we present deeper analysis and investigate the 2D scaling properties of these fracture surfaces. We showed that the properties of scaling invariance are anisotropic and evidenced the existence of two peculiar directions on the post-mortem fracture surface caracterized by two different scaling exponents: the direction of the crack growth and the direction of the crack front. These two exponents were found to be universal, independent of the crack growth velocity, in both silica glass and aluminum alloy, archetype of brittle and ductile material respectively. Moreover, the 2D structure function that fully characterizes the scaling properties of the fracture surface was shown to take a peculiar form similar to the one predicted by some models issued from out-of-equilibrium statistical physics. This suggest some promising analogies between dynamic phase transition models and the stability of a crack front pinned/unpinned by the heterogenities of the material.
description: 4 pages