cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
USCT Image Reconstruction: Acceleration using Gauss-Newton Preconditioned Conjugate Gradient
Creators: name: Wang, H.
name: Gemmeke, H.
name: Hopp, T.
name: Hesser, J.
Publisher: name: KIT Scientific Publishing
Year: 2017

description: Ultrasound transmission tomography offers quantitative characterization of the tissue or materials by their speed of sound and attenuation. Reconstruction of such images is an inverse problem which is solved iteratively based on a forward model of the Helmholtz equation by paraxial approximation and thus is time-consuming. Hence, developing optimizers that decrease this time, in particular reducing the number of forward propagations is of high relevance in order to bring this technology into clinical practice. In this paper, we solve the inverse problem of reconstruction in a two-level strategy, by an outer and an inner loop. At each iteration of the outer loop, the system is linearized and this linear subproblem is solved in the inner loop with a preconditioned conjugate gradient (CG). A standard Cholesky preconditioning method based on the system matrix is compared with a matrix-free Quasi-Newton update approach, where a preconditioned matrix-vector product is computed at the beginning of every CG iteration. We also use a multigrid scheme with multi-frequency reconstruction to get a convergent rough reconstruction at a lower frequency and then refine it on a higher-resolution grid. The Cholesky preconditioning reduces the number of CG iterations by approx. 70%~85%; but the computation time for determining the system matrix for the Cholesky preconditioner is dominating, offsetting the gains of the reduction of iterations. The matrix-free preconditioning method saves approx. 30% of the computation time on average for single-frequency and multi-frequency reconstruction. For the robust multifrequency reconstruction, we test three breast-like numerical phantoms resulting in a deviation of 0.13 m/s on average in speed of sound reconstruction and a deviation of 5.4% on average in attenuation reconstruction, from the ground truth simulation.
Gauge Coupling Unification in the Standard Model
Creators: name: Barger, V.
name: Jiang, Jing
name: Langacker, Paul
name: Li, Tianjun
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The string landscape suggests that the supersymmetry breaking scale can be high, and then the simplest low energy effective theory is the Standard Model (SM). We show that gauge coupling unification can be achieved at about 10^{16-17} GeV in the SM with suitable normalizations of the U(1)_Y. Assuming grand unification scale supersymmetry breaking, we predict that the Higgs mass range is 127 GeV to 165 GeV, with the precise value strongly correlated with the top quark mass and SU(3)_C gauge coupling. We also present 7-dimensional orbifold grand unified theories in which such normalizations for the U(1)_Y and charge quantization can be realized.
description: RevTex4, 4 pages, 2 figures
The Free Electron Gas in Cavity Quantum Electrodynamics
Creators: name: Rokaj, Vasil
name: Ruggenthaler, Michael
name: Eich, Florian G.
name: Rubio, Angel
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Cavity modification of material properties and phenomena is a novel research field largely motivated by the advances in strong light-matter interactions. Despite this progress, exact solutions for extended systems strongly coupled to the photon field are not available, and both theory and experiments rely mainly on finite-system models. Therefore a paradigmatic example of an exactly solvable extended system in a cavity becomes highly desireable. To fill this gap we revisit Sommerfeld's theory of the free electron gas in cavity quantum electrodynamics (QED). We solve this system analytically in the long-wavelength limit for an arbitrary number of non-interacting electrons, and we demonstrate that the electron-photon ground state is a Fermi liquid which contains virtual photons. In contrast to models of finite systems, no ground state exists if the diamagentic $\textbf{A}^2$ term is omitted. Further, by performing linear response we show that the cavity field induces plasmon-polariton excitations and modifies the optical and the DC conductivity of the electron gas. Our exact solution allows us to consider the thermodynamic limit for both electrons and photons by constructing an effective quantum field theory. The continuum of modes leads to a many-body renormalization of the electron mass, which modifies the fermionic quasiparticle excitations of the Fermi liquid and the Wigner-Seitz radius of the interacting electron gas. Lastly, we show how the matter-modified photon field leads to a repulsive Casimir force and how the continuum of modes introduces dissipation into the light-matter system. Several of the presented findings should be experimentally accessible.
Particle-number conservation within self-consistent random-phase approximation
Creators: name: Dang, Nguyen Dinh
Publisher: name: arXiv
Year: 2004
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The self-consistent random-phase approximation (SCRPA) is reexamined within a multilevel-pairing model with double degeneracy. It is shown that the expressions for occupation numbers used in the original version of SCRPA violate the particle number for non-symmetric particle-hole ($ph$) spectra. A renormalization is introduced to restore the particle number, which leads to the expressions of occupation numbers similar to those derived by Hara et al. for the ph case. The results of calculations within the $ph$-symmetric case show that this number-conserving SCRPA yields the energies of the ground state and first excited state of the system with $Ω+2$ particles relative to the ground state of the system with $Ω$ particles in close agreement with those obtained within the original SCRPA. However it gives a slightly larger correlation energy.
description: 14 pages, 4 figures, to be published in Physical Review C
BACK TO THE BASICS: WHAT DOES THE MARKET TELL US ABOUT BASIS?
Creators: name: Fischer, Matthew J.
name: Isengildina-Massa, Olga
name: Curtis, Charles E.
name: Boys, Kathryn A.
name: Fischer, Matthew J.
name: Isengildina-Massa, Olga
name: Curtis, Charles E.
name: Boys, Kathryn A.
Publisher: name: Unknown
Year: 2011
Subjects: subject: Marketing
subject: FOS: Economics and business

description: This study explores market forces that affect harvest grain basis for corn, soybeans, and wheat in a grain deficit market. The findings indicate that implied basis (cash forward bid less harvest futures), nearby HHO price, and log of open interest on the harvest futures contract can be used to predict 33 to 99 percent of the variation in harvest basis at selected South Carolina locations.
Does tariff escalation affect export shares: The case of cotton and coffee in global trade
Creators: name: Narayanan G, Badri
name: Khorana, Sangeeta
name: Narayanan G, Badri
name: Khorana, Sangeeta
Publisher: name: Unknown
Year: 2011
Subjects: International Relations/Trade

description: Many studies show that Tariff Escalation (TE) lowers export shares in many of the processing sectors, given their higher level of protection. However, there are instances when the export shares of processed sectors are higher despite the existence of TE. We examine both these contrasting cases of TE in this paper. On the one hand, there is TE in coffee and coffee products in developing countries, which lead in raw coffee exports and lag in roasted coffee exports. On the other hand, there is a similar pattern of TE in developing countries, which are leading exporters of cotton textiles, but not as much of raw cotton. This raises the question whether TE has a systematic impact on a country’s export shares. We use a widely used economy-wide model named GTAP (Global Trade Analysis Project) and its accompanying Data Base 2004 version. We supplement the data with UN commodity statistics and other country-specific and industry-specific sources to split cotton, cotton textiles, coffee and coffee products from aggregated sectors in this dataset. We analyze different policy scenarios of bringing the tariffs for processing sectors to the levels of their raw materials for the value-chains of cotton and coffee. Our results focusing on export shares show that TE can lead to higher or lower export shares depending on various other factors such as the actual tariff differences across sectors and countries.
Upper extremity impairment, activity limitation, and participation restriction in individuals with chronic stroke
Creators: name: Harris, Jocelyn Ellen
Publisher: name: University of British Columbia
Year: 2009

description: The upper extremity is used in virtually every aspect of daily life whether in self-care, work, or recreational activities. Upper extremity impairment following stroke is common and thus factors contributing to its function (e.g., strength, sensation, tone, hand dominance) following stroke could critically impact independence in daily activities and quality of life. The purpose of this study was to determine the relationship between variables of upper extremity impairment and activity limitation (assessed by performance on measures of ADL) and participation restriction (assessed by measures of satisfaction and quality of life), and to determine the effect of hand dominance on impairment and activity in individuals with chronic stroke. Ninety-three community dwelling individuals with chronic stroke participated in a clinical assessment of upper extremity function. The results of this study revealed that variables of upper limb impairment particularly muscle weakness and severity of motor impairment, did contribute to activity limitation and participation restriction in individuals with chronic stroke. s Further, the results suggested that if the dominant hand (versus the non-dominant) was affected by the stroke, individuals incurred less impairment (strength, tone, and pain) but not activity limitation. It is suggested that clinicians working in stroke rehabilitation focus on strength training of the affected upper limb to minimize dependence in ADL and enhance community living. As well, clinicians need to consider whether the affected hand is dominant or nondominant. Our results suggest that the affected non-dominant hand has greater impairment (versus affected dominant) thus enforcing the use of the affected non-dominant hand may reduce musculoskeletal changes and impairment, thereby enhancing motor performance post stroke.
CHEST IMAGING FEATURES OF COVID-19 PNEUMONIA
Creators: name: MUNTEAN, PETRU EMIL
Publisher: name: figshare
Year: 2020
Subjects: Medicine

description: The accuracy of chest CT in symptomatic patientswith COVID-19 is high, but used as a single diagnostictest, CT can not accurately diagnose orexclude coronavirus infection and should not berelied upon as a screening or diagnostic tool forCOVID-19 pneumonia1. Chest CT is rather helpfulin evaluating the complications of COVID-19 andis indicated in patients with COVID-19 and worseningrespiratory symptoms2. The most commonimaging findings are of an atypical or organisingpneumonia, with bilateral involvement, especiallyof the lower lobes2.
Border Effects on Spatial Price Transmission between Fresh Tomato Markets in Ghana and Burkina-Faso: Any Case for Promoting Trans-border Trade in West Africa?
Creators: name: Amikuzuno, Joseph
name: Amikuzuno, Joseph
Publisher: name: Unknown
Year: 2011
Subjects: subject: International Relations/Trade
subject: Price Transmission
subject: Border
subject: Tomato
subject: Ghana
subject: Burkina-Faso

description: Cross-border trade in food commodities within sub-regional economic blocks in Sub-Sahara Africa (SSA) is believed to be faster, cheaper, more convenient and welfare-enhancing than trade between SSA countries and the USA or EU. The difficulty of commodity arbitrage across borders in SSA is however a fundamental impediment to price transmission, market integration and the realisation of the welfare-enhancing role of cross-border trade. This study examines the impact of border and distance on price transmission between tomato in Ghana and Burkina-Faso. The analysis applies a linear and a regime-switching vector error correction model to estimate wholesale prices of tomato in four tomato markets in Ghana and a producer market in Burkina-Faso. The estimated parameters contain evidence of border and distance effects. This is expected since high transfer costs, including cross-border formal and non-formal tariffs are incurred by traders in moving tomato across the border. Moreover, the perishable nature of tomato, and the poor quality of roads and transportation facilities linking markets on both sides of the border imply additional risks, and constrain Just in Time delivery and price transmission from producing to retail and consuming markets. The findings have implications for interstate trade between landlocked and coastal countries in West Africa.
Families In Wild Multimedia: A Multimodal Database for Recognizing Kinship
Creators: name: Robinson, Joseph P.
name: Khan, Zaid
name: Yin, Yu
name: Shao, Ming
name: Fu, Yun
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Kinship, a soft biometric detectable in media, is fundamental for a myriad of use-cases. Despite the difficulty of detecting kinship, annual data challenges using still-images have consistently improved performances and attracted new researchers. Now, systems reach performance levels unforeseeable a decade ago, closing in on performances acceptable to deploy in practice. Like other biometric tasks, we expect systems can receive help from other modalities. We hypothesize that adding modalities to FIW, which has only still-images, will improve performance. Thus, to narrow the gap between research and reality and enhance the power of kinship recognition systems, we extend FIW with multimedia (MM) data (i.e., video, audio, and text captions). Specifically, we introduce the first publicly available multi-task MM kinship dataset. To build FIW MM, we developed machinery to automatically collect, annotate, and prepare the data, requiring minimal human input and no financial cost. The proposed MM corpus allows the problem statements to be more realistic template-based protocols. We show significant improvements in all benchmarks with the added modalities. The results highlight edge cases to inspire future research with different areas of improvement. FIW MM supplies the data needed to increase the potential of automated systems to detect kinship in MM. It also allows experts from diverse fields to collaborate in novel ways.
Future Universe With w < -1 Without Big Smash
Creators: name: Srivastava, S. K.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: It is demonstrated that if cosmic dark energy behaves like a fluid with equation of state $p = {\rm w} ρ(p$ and $ρ$ being pressure and energy density respectively) as well as generalized Chaplygin gas simultaneously, Big Rip or Big smash problem does not arise even for equation of state parameter ${\rm w} < -1$.Unlike other phantom models, here, scale factor for the future universe is found regular for all time.
description: 11 pages. To appear in Phys. Lett. B
Study of Rice Marketing System in Iran
Creators: name: Feizabadi, Yaser
name: Feizabadi, Yaser
Publisher: name: Unknown
Year: 2011
Subjects: subject: Marketing
subject: FOS: Economics and business
subject: Mazandaran Province
subject: Marketing Margin
subject: Rice

description: Rice comes second after wheat in Iran`s food consumption economy. Rising population and recent growth in GDP has made Iran one of the greatest rice importer countries all over the world. That is why rice marketing has always been a controversial issue in Iran`s agricultural economics. To study rice marketing system in Iran, this paper aims to calculate rice marketing margin, market efficiency and marketing cost coefficient in seaside Mazandaran province( where 70 percent of domestic rice production is obtained )Over the period 2000-2010. Results show that firstly HYV`s wholesale marketing margin is less than local varieties in 2000 while this trend is reversed in 2010. Secondly, retail marketing margin, total marketing margin, market efficiency and cost marketing coefficient for local varieties are all greater than HYV. Consequently, agricultural cooperative`s encouragement would lead to decrease in rice marketing margin and role of traders and raises rice farmers earnings
Sindroame bacteriemice
Creators: name: MUNTEAN, PETRU EMIL
Publisher: name: figshare
Year: 2020
Subjects: Medicine

description: Deși au fost realizate progrese mari în ultimii ani în domeniul cercetării medicale, problema infecțiilor grave cu evoluție spre septicemie rămâne încă incomplet elucidata. Sindroamele bacteriemice rămân și în prezent o cauză majoră de morbiditate respective mortalitate, motiv pentru care trebuie acordată o atenție deosebită studiului etiologic, a mecanismelor patologice cat si a posibilităților de tratament și de profilaxie in acest sens.Utilizarea incorectă și abuzivă a antibioticelor cu spectru larg in spitale, duce la disbacterioză prin distrugerea florei antagoniste principale, urmată de înmulțirea germenilor condiționat patogeni, unde un efect tardiv al tratamentului de tip abuziv și neadecvat cu antibiotic îl reprezintă selectarea de tulpini rezistente la acțiunea antibioticelor și chimioterapicelor.
Impact of Off-farm Income on Farm Efficiency in Slovenia
Creators: name: Bojnec, Stefan
name: Ferto, Imre
name: Bojnec, Stefan
name: Ferto, Imre
Publisher: name: Unknown
Year: 2011
Subjects: subject: Farm Management
subject: Off-farm income
subject: Stochastic frontier analysis
subject: Panel regression
subject: Quantile regression
subject: Slovenia

description: The paper investigates the impact of off-farm income on farm technical efficiency for the Slovenian Farm Accountancy Data Network farms in the years 2004-2008. Farm stochastic frontier time-varying decay inefficiency is positively associated with total utilised agricultural areas and total labour input, and vice versa with intermediate consumption and fixed assets. We find a positive association between farm technical efficiency and the off-farm income. Farm technical efficiency has increased steadily over time, the process, which was led by the off-farm spill over effect and most efficient farms. Farm technical efficiency is also positively associated with economic farm size, while association with subsidies is mixed depending on the estimation procedure. Quantile regression confirms the positive and significant associations between farm technical efficiency and off-farm income, and between farm technical efficiency and farm economic size, as well as also the positive association between farm technical efficiency and subsidies, but the results are sensitive by quantiles.
$T_c$ and Pauli limited critical field of $\text{Sr}_2\text{Ru}\text{O}_4$: uniaxial strain dependence
Creators: name: Yu, Yue
name: Brown, Stuart
name: Raghu, S.
name: Yang, Kun
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Variations of critical temperature $T_c$ and in-plane critical field $H_{c2}$ of $\text{Sr}_2\text{Ru}\text{O}_4$ under uniaxial stress have recently been reported. We compare the strain dependence of $T_c$ and $H_{c2}$ in various pairing channels ($d$-wave, extended s-wave and $p$-wave) with the experimental observations, by studying a three-band tight-binding model that includes effects of spin-orbit and Zeeman couplings and a separable pairing interaction. Our study helps narrow down the possibility of pairing channels. The importance of the multi-band nature of $\text{Sr}_2\text{Ru}\text{O}_4$ is also highlighted.
title: Essays on firms, technology, and macroeconomics
Creators: name: Gao, Xijie
Publisher: name: London School of Economics and Political Science (LSE)
Year: 2020

description: This thesis consists of three chapters. Chapter 1 studies the role of marketing in the economy. Using aggregate and firm-level data, I find that aggregate marketing intensity in the US increased sharply around the mid-1990s, which coincides with a rapid rise of elasticity between firm-level Marketing Production Cost Ratio and markup. To explain these facts, I develop a model with heterogeneous firms and endogenous markups in which firms engage in marketing to signal their quality. I use a calibrated version of the model to quantify the impact of information frictions and marketing on aggregate productivity. I find that quality information revealed by marketing is valuable and access to marketing cannot undo the information frictions completely. Chapter 2 examines the impact of zombie firms on resource allocation. Using firm-level data in China, I show that zombie firms are larger, less productive, and receive a higher subsidy rate on average. The difference in average subsidy rate between zombies and non-zombies reflects both the selection criterion of zombies and the underlying joint distribution of subsidy rate and productivity. I develop a model with heterogeneous firms to quantify the impact of zombies on aggregate productivity. Quantitative exercise shows that reducing the dispersion in subsidy rate across firms can lead to significant productivity gains, while policies that increase the exit rate of zombies have limited productivity effects. Chapter 3 establishes two facts along with the rise of information technology: (i) the output from the information sector is more intensively used as an intermediate input; (ii) the wage of information workers and their total employment increase relative to those of non-information workers. To understand the causes, we develop a two-sector accounting framework with sector-factor specific technical changes. We find that labor-augmenting technical change is important in explaining the observed change in wage premium and intermediate shares.
Impacts of EU Accession on Hungarian Primary and Processed Agricultural Trade
Creators: name: Jambor, Attila
name: Jambor, Attila
Publisher: name: Unknown
Year: 2011
Subjects: subject: Agribusiness
subject: EU accession
subject: agri-food trade
subject: primary and processed products

description: In 2004, Hungary joined the European Union (EU) along with nine other Central and Eastern European Countries, causing several changes in the field of agriculture. One of the major changes was the transformation of national agri-food trade. The aim of the paper is to analyse the effects of EU accession on the Hungarian primary and processed agri-food trade, especially considering revealed comparative advantages, by using recent data. Results suggest that EU accession raised the intensity of trade contacts but had a negative impact on trade balance. Nominal values of both exports and imports increased after 2004, however, Hungarian agriculture is increasingly based on raw material export and processed food import. It also turned out that revealed comparative advantages of Hungarian primary agri-food products in EU15 remained almost constant after accession, while comparative advantages of processed agri-food products has been gradually increasing by time and even reached the satisfactory level in some cases. From the policy perspective, it is apparent that there is a need for deeper structural reforms of the Hungarian agricultural and food sector is the future.
Radiation from an inertial mirror horizon
Creators: name: Good, Michael
name: Abdikamalov, Ernazar
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The purpose of this study is to investigate radiation from asymptotic zero acceleration motion where a horizon is formed and subsequently detected by an outside witness. A perfectly reflecting moving mirror is used to model such a system and compute the energy and spectrum. The trajectory is asymptotically inertial (zero proper acceleration)-ensuring negative energy flux (NEF), yet approaches light-speed with a null ray horizon at a finite advanced time. We compute the spectrum and energy analytically.
description: 10 pages, 6 figures, 1 table; Accepted for publication in Universe; Selected Papers from the 17th Russian Gravitational Conference -International Conference on Gravitation, Cosmology and Astrophysics (RUSGRAV-17)
Probing quantum decoherence in atmospheric neutrino oscillations with a neutrino telescope
Creators: name: Morgan, Dean
name: Winstanley, Elizabeth
name: Brunner, Jurgen
name: Thompson, Lee F.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Quantum decoherence, the evolution of pure states into mixed states, may be a feature of quantum gravity. In this paper, we show how these effects can be modelled for atmospheric neutrinos and illustrate how the standard oscillation picture is modified. We examine how neutrino telescopes, such as ANTARES, are able to place upper bounds on these quantum decoherence effects.
description: Discussion of event spectra added; version accepted for publication in Astroparticle Physics; 38 pages, 15 figures, uses elsart.cls
title: Auswirkungen der Industrialisierung auf die Klanglandschaft des Ruhrgebiets (1871 bis 1914) und deren mediale Darstellung
Creators: name: Högerle, Florian
Publisher: name: Fachhochschule Dortmund
Year: 2021
Subjects: subject: 791 Öffentliche Darbietungen, Film, Rundfunk

description: Das Ziel der vorliegenden Masterarbeit ist es, die wichtigsten Klänge der Zeit der Industrialisierung im Ruhrgebiet herauszufinden und diese in den historischen Kontext einzuordnen. Hierzu werden Berichte aus verschiedenen Quellen (Historie, Wirtschaft und Sozialkunde) herangezogen, um das Thema von verschieden Blickpunkten zu analysieren. Die wichtigsten Ergebnisse dieser Arbeit sind die starken Wahrnehmungsunterschiede von Lärm zwischen verschiedenen sozialen Schichten, die Identifizierung von Transportmitteln als wesentliche Veränderung der Klanglandschaft und die Abgrenzung der Industriegeräusche von den Geräuschen der Stadt. Weiterhin wird die Klanglandschaft des Ruhrgebiets in ausgewählten Filmen der Neuzeit untersucht und auf Töne hingewiesen, die das Ruhrgebiet auditiv als einzigartig darstellen.
description: The aim of this master thesis is to find out the most important sounds of the time of industrialization in the Ruhr area and to put them into the historical context. For this purpose, reports from different sources (history, economics and social studies) are used to analyze the topic from different points of view. The main results of this work are the strong differences in perception between different social classes of noise, the identification of transportation as a major change in the soundscape and the demarcation of industrial noise from urban noise. Furthermore, the soundscape of the Ruhr area is examined in selected films of the modern era and sounds are pointed out that auditorily portray the Ruhr area as unique.
Technical efficiency and technology gaps in beef cattle production systems in Kenya: A stochastic metafrontier analysis
Creators: name: Otieno, David Jakinda
name: Hubbard, Lionel J.
name: Ruto, Eric
name: Otieno, David Jakinda
name: Hubbard, Lionel J.
name: Ruto, Eric
Publisher: name: Unknown
Year: 2011
Subjects: subject: Livestock Production/Industries
subject: Technical efficiency
subject: technology gap
subject: beef cattle
subject: production systems
subject: stochastic metafrontier
subject: Kenya.

description: In this study the stochastic metafrontier method is used to investigate technical efficiency and technology gaps across three main beef cattle production systems in Kenya. Results show that there is significant inefficiency in nomadic and agro-pastoral systems. Further, in contrast with ranches, these two systems were found to have lower technology gap ratios. The average pooled technical efficiency was estimated to be 0.69, which suggests that there is considerable scope to improve beef production in Kenya
Total Factor Productivity and the Efficiency of Rice Farms in Bangladesh: a Farm Level Panel Data Comparison of the Pre- and Post-Market Reform Period
Creators: name: Alam, Mohammad Jahangir
name: Begum, Ismat Ara
name: Rahman, Sanzidur
name: Buysse, Jeroen
name: Van Huylenbroeck, Guido
name: Alam, Mohammad Jahangir
name: Begum, Ismat Ara
name: Rahman, Sanzidur
name: Buysse, Jeroen
name: Van Huylenbroeck, Guido
Publisher: name: Unknown
Year: 2011
Subjects: Farm Management

description: The market reform policy in agriculture and the trade liberalization during the early 1990s has led to structural changes in the agricultural sector of Bangladesh. The question of whether market reform policies in Bangladesh facilitated rice production is examined in this paper. This paper uses stochastic frontier production function to measure total factor productivity (TFP), technical change, and technical efficiency change covering the period of pre-market reform (1987) and post-market reform (2000 and 2004). To fulfill the objective, the study used panel data of 73 same farm households from a field survey of 1987–1988, 1999-2000 and 2003-04. It is evident from the study results that over time period (1987-2004), the TFP increased (31.76%) only due to upward shift in the technology. Technological change increased 59.99% in post reform period. However, although TFP increased substantial inefficiencies remain in Bangladesh rice sector. Technical efficiency change (-34.46%) developed negatively over the years of study at farm level. Market reform policy has negative impact on technical efficiency change but positive in technical change and TFP change although all are declining over the time period. Therefore, government policies need for further reform of domestic market and trade policies focusing on institutional changes, tariff and nontariff barriers in order to develop a competitive environment in rice sector.
First Study for the Pentaquark Potential in SU(3) Lattice QCD
Creators: name: Okiharu, Fumiko
name: Suganuma, Hideo
name: Takahashi, Toru T.
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: The static penta-quark (5Q) potential $V_{\rm 5Q}$ is studied in SU(3) lattice QCD with $16^3\times 32$ and $β$=6.0 at the quenched level. From the 5Q Wilson loop, $V_{\rm 5Q}$ is calculated in a gauge-invariant manner, with the smearing method to enhance the ground-state component. $V_{\rm 5Q}$ is well described by the OGE plus multi-Y Ansatz: a sum of the OGE Coulomb term and the multi-Y-type linear term proportional to the minimal total length of the flux-tube linking the five quarks. Comparing with ${\rm Q \bar Q}$ and 3Q potentials, we find a universality of the string tension, $σ_{\rm Q \bar Q} \simeq σ_{\rm 3Q} \simeq σ_{\rm 5Q}$, and the OGE result for Coulomb coefficients.
description: 4 pages, 5 figures
Quantum Transport in Semiconductor Nanostructures
Creators: name: Beenakker, C. W. J.
name: van Houten, H.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: I. Introduction (Preface, Nanostructures in Si Inversion Layers, Nanostructures in GaAs-AlGaAs Heterostructures, Basic Properties). II. Diffusive and Quasi-Ballistic Transport (Classical Size Effects, Weak Localization, Conductance Fluctuations, Aharonov-Bohm Effect, Electron-Electron Interactions, Quantum Size Effects, Periodic Potential). III. Ballistic Transport (Conduction as a Transmission Problem, Quantum Point Contacts, Coherent Electron Focusing, Collimation, Junction Scattering, Tunneling). IV. Adiabatic Transport (Edge Channels and the Quantum Hall Effect, Selective Population and Detection of Edge Channels, Fractional Quantum Hall Effect, Aharonov-Bohm Effect in Strong Magnetic Fields, Magnetically Induced Band Structure).
description: 111 pages including 109 figures; this review from 1991 has retained much of its usefulness, but it was not yet available electronically
Comparing technical efficiency of organic and conventional coffee farms in Nepal using data envelopment analysis (DEA) approach
Creators: name: Poudel, Krishna Lal
name: Yamamoto, Naoyuki
name: Sugimoto, Yasuhiro
name: Nishiwaki, Aya
name: Kano, Hideyuki
name: Poudel, Krishna Lal
name: Yamamoto, Naoyuki
name: Sugimoto, Yasuhiro
name: Nishiwaki, Aya
name: Kano, Hideyuki
Publisher: name: Unknown
Year: 2011
Subjects: subject: Productivity Analysis
subject: Production frontier
subject: Resource use
subject: Technical efficiency
subject: Organic
subject: Altitude

description: Data Envelopment Analysis (DEA) approach used to estimate technical efficiency and followed by regressing the technical efficiency scores to farm specific characters under tobit regression model. Primary data was collected from random samples of 240 (120 from each) coffee famers. Mean technical efficiency score was 0.89 and 0.83 in organic and conventional coffee farming respectively. Farms operating under CRS, DRS and IRS were 31.67, 3.83 and 37.5% respectively in organic coffee and 29.17, 25 and 45.83% respectively in conventional farming areas. Tobit regression showed the variation in technical efficiency was related education, farm experience and training/extension services and excess to credit.
Measurement of the branching fractions of psi(2S) -> 3(pi+pi-) and J/psi -> 2(pi+pi-)
Creators: name: Ablikim, M.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Using data samples collected at sqrt(s) = 3.686GeV and 3.650GeV by the BESII detector at the BEPC, the branching fraction of psi(2S) -> 3(pi+pi-) is measured to be [4.83 +- 0.38(stat) +- 0.69(syst)] x 10^-4, and the relative branching fraction of J/psi -> 2(pi+pi-) to that of J/psi -> mu+mu- is measured to be [5.86 +- 0.19(stat) +- 0.39(syst)]% via psi(2S) -> (pi+pi-)J/psi, J/psi -> 2(pi+pi-). The electromagnetic form factor of 3(pi+pi-) is determined to be 0.21 +- 0.02 and 0.20 +- 0.01 at sqrt(s) = 3.686GeV and 3.650GeV, respectively.
description: 17pages, 7 figures, submitted to Phys. Rev. D
Anomalous pressure dependence of the electronic transport and anisotropy in SrIrO3 films
Creators: name: Zaitsev, A. G.
name: Beck, A.
name: Jaiswal, A. K.
name: Singh, R.
name: Schneider, R.
name: Tacon, M. Le
name: Fuchs, D.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Iridate oxides display exotic physical properties that arise from the interplay between a large spin-orbit coupling and electron correlations. Here, we present a comprehensive study of the effects of hydrostatic pressure on the electronic transport properties of SrIrO3 (SIO), a system that has recently attracted a lot of attention as potential correlated Dirac semimetal. Our investigations on untwinned thin films of SIO reveal that the electrical resistivity of this material is intrinsically anisotropic and controlled by the orthorhombic distortion of the perovskite unit cell. These effects provide another evidence for the strong coupling between the electronic and lattice degrees of freedom in this class of compounds. Upon increasing pressure, a systematic increase of the transport anisotropies is observed. The anomalous pressure-induced changes of the resistivity cannot be accounted for by the pressure dependence of the density of the electron charge carriers, as inferred from Hall effect measurements. Moreover, pressure-induced rotations of the IrO6 octahedra likely occur within the distorted perovskite unit cell and affect electron mobility of this system.
Identification and characterization of an alternative canalicular bile acid transporter
Creators: name: Lam, Ping
Publisher: name: University of British Columbia
Year: 2009

description: In vertebrates, bile flow is essential for movement of water and solutes across the liver canalicular membrane. The formation of bile is contributed by the active transport of bile acids and other organic solutes (Coleman 1987; Nathanson and Boyer 1991; Erlinger 1996). In recent years, the molecular motor of canalicular bile acid secretion has been identified to be a member of the ATP Binding Cassette transporter superfamily, known as Sister of p-glycoprotein (Spgp) or Bile Salt Efflux Pump (Bsep) (Childs et al. 1995; Gerloff et al. 1998). In humans, mutations in spgp cause a severe liver disease known as type 2 intrahepatic cholestasis (PFIC2), which is characterized by low bile acid output (Strautnieks et al. 1998; Jansen et al. 1999). Spgp[sup -/-] mice produce a cholestatic phenotype that is less severe than human PFIC2 (Wang et al. 2001). The work in this thesis investigated the molecular mechanism(s) of bile acid secretion in spgp[sup -/-] mice. Hepatic responses of bile flow and bile acid secretion were significantly stimulated by cholic acid (CA) feeding in mutant mice. In addition, the capacity of total bile acid secretion was comparable to wildtype mice, compatible with the hypothesis that additional molecular mechanisms exist for bile acid secretion. To investigate whether another ATP-dependent bile acid transport may account for the bile acid clearance in spgp[sup -/-] mice, mRNA and protein expression data were studied. The expression of Mdr1a associated with resistance to multiple anticancer drugs, was dramatically increased in spgp[sup -/-] mice. Kinetic studies showed ATP-dependent bile acid transport in canalicular membrane vesicles isolated from control mice but not in those from spgp[sup -/-] mice. To reconcile this difference between in vivo data and in vitro canalicular membrane transport measurement, membrane vesicles containing highly overexpressed hamster Pgp (a homolog of mouse mdr1a) was used to demonstrate ATP-dependent bile acid transport. The kinetic parameters of Pgp-mediated ATP-dependent taurocholate transport were compatible with a low-affinity transporter. Taken together, these studies have provided evidence that Mdrla is capable of transporting bile acids, which has not been recognized previously.
A Note on the Eigenvalue Problem in the su(1,1)-Algebra
Creators: name: Nishiyama, S.
name: Providencia, C.
name: da Providencia, J.
name: Tsue, Y.
name: Yamamura, M.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Normalization constant in the eigenstate appearing in the eigenvalue problem of the su(1,1)-algebra is discussed. This normalization constant is expressed in terms of the Gauss' hypergeometric series which is not absolutely convergent. It is proved that this series is obtained as a certain limit of an absolutely convergent series, which was conjectured in the previous paper.
description: 9 pages, 2 figures
Topological Constraint Theory and Rigidity of Glasses
Creators: name: Bauchy, Mathieu
Publisher: name: arXiv
Year: 2020
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Topological constraint theory has become an increasingly popular tool to predict the compositional dependence of glass properties or pinpoint promising compositions with tailored functionalities. This approach reduces complex disordered networks into simpler mechanical trusses. Thereby, topological constraint theory captures the important atomic topology that controls macroscopic properties while filtering out less relevant second-order structural details. As such, topological constraint theory can be used to decode the genome of glass, that is, to identify and decipher how the basic structural building blocks of glasses control their engineering properties---in the same way as the human genome offers information that serves as a blueprint for an individual's growth and development. Thanks to its elegance and simplicity, topological constraint theory has enabled the development of various physics-based models that can analytically predict various properties of glass. In this Chapter, I introduce some general background in glass science, concepts of atomic rigidity, and topological constraint theory. The topological constraints enumeration scheme is presented for various archetypical glasses and is used to understand the origin of their glass-forming ability. Finally, various topological models enabling the prediction of glass properties are reviewed, with a focus on hardness, fracture toughness, viscosity, fragility, glass transition temperature, and dissolution kinetics.
A Climate, Land, Energy, and Water nexus assessment of the Tana River Basin in Kenya. Geo-Spatially Explicit Agriculture Focused CLEWs Model
Creators: name: Eltom, Osman
Publisher: name: Zenodo
Year: 2024

description: This project involves a model developed using the Open Source Energy Modeling System (OSeMOSYS) to optimize resource allocation within the Tana River Basin. The model integrates land, water, energy, and agriculture systems to explore sustainable management strategies for the basin. By leveraging GIS data, the model assesses various land uses such as cropland, rangeland, wetlands, and forest areas. The analysis focuses on key crops, including coffee, maize, rice, sorghum, and cowpea, which play critical roles in the basin’s economy and food security.
Using a Discrete Choice Experiment to Elicit Consumers’ WTP for Health Risk Reductions Achieved By Nanotechnology in the UK
Creators: name: Erdem, Seda
name: Rigby, Dan
name: Erdem, Seda
name: Rigby, Dan
Publisher: name: Unknown
Year: 2011
Subjects: subject: Health Economics and Policy
subject: Discrete Choice Experiments
subject: Nanotechnology
subject: FOS: Nanotechnology
subject: Nanosensors
subject: Health Risks
subject: Grids
subject: UK

description: We present research findings on consumers’ willingness to pay (WTP) for reductions in the level of foodborne health risks. The research addresses how such valuations are affected by the means of which the risk reduction is delivered and the methods of risk presentations used in choice tasks. In this case, the research has two treatments. In the first treatment, the comparison is between risk reductions achieved by an improvement in the food system in general (e.g., more stringent regulations and inspection regimes) within the slaughter and meat processing stages of the food chain, as opposed to a risk reduction achieved via innovations in food packaging using nanotechnology, which is the use of nanosensors in packaging. If there is a contamination in packaging, nanosensors reveal a colour change on the packaging material. In the second treatment, the comparison is between valuations of risk reductions in which reductions in risks are presented via absolute values and grids and absolute values together. Both comparisons are achieved via split sample Discrete Choice Experiment surveys. The difference between consumers’ valuations of foodborne risk reductions provides an implicit value for nanotechnology (i.e., WTP to avoid) and the effect of risk grids on choices people make. General results show the existence of heterogeneity in British consumers’ preferences. The effects of nanosensors and risk grids on consumers’ choices are not strong across the models. The valuations of health risk reductions show some variations across the models in both treatment groups.
Women’s Rights and Development
Creators: name: Fernandez, Raquel
name: Fernandez, Raquel
Publisher: name: Unknown
Year: 2010
Subjects: subject: Labor and Human Capital
subject: Women’s Rights
subject: Property Rights
subject: Economic Development

description: Why has the expansion of women’s economic and political rights coincided with economic development? This paper investigates this question, focusing on a key economic right for women: property rights. The basic hypothesis is that the process of development (i.e., capital accumulation and declining fertility) exacerbated the tension in men’s conflicting interests as husbands versus fathers, ultimately resolving them in favor of the latter. As husbands, men stood to gain from their privileged position in a patriarchal world whereas, as fathers, they were hurt by a system that afforded few rights to their daughters. The model predicts that declining fertility would hasten reform of women’s property rights whereas legal systems that were initially more favorable to women would delay them. The theoretical relationship between capital and the relative attractiveness of reform is non-monotonic but growth inevitably leads to reform. I explore the empirical validity of the theoretical predictions by using cross-state variation in the US in the timing of married women obtaining property and earning rights between 1850 and 1920.
Social Capital and Political Accountability
Creators: name: Nannicini, Tommaso
name: Stella, Andrea
name: Tabellini, Guido
name: Troiano, Ugo
name: Nannicini, Tommaso
name: Stella, Andrea
name: Tabellini, Guido
name: Troiano, Ugo
Publisher: name: Unknown
Year: 2010
Subjects: subject: Labor and Human Capital
subject: Social Capital
subject: Culture
subject: Political Agency

description: In this paper, we empirically investigate a channel through which social capital may improve economic wellbeing and the functioning of institutions: political accountability. The main idea is that voters who share norms of generalized morality demand higher standards of behavior on their elected representavtives, are more willing to bear the cost of acquiring information, and are more likely to base their vote on criteria of social welfare rather than (narrow) personal interest. We take this conjecture to the data using information on the Italian members of Parliament in the postwar period (1948–2001). The empirical evidence shows that the electoral punishment of political misbehavior is considerably larger in electoral districts with high social capital, where social capital is measured by blood donation, and political misbehavior refers to receiving a request of criminal prosecution or shirking in parliamentary activity. Accordingly, episodes of political misbehavior are less frequent in electoral districts with high social capital.
description: Replaced with revised version of paper 02/05/12.
Juvenile Delinquency and Conformism
Creators: name: Patacchini, Eleonora
name: Zenou, Yves
name: Patacchini, Eleonora
name: Zenou, Yves
Publisher: name: Unknown
Year: 2010
Subjects: subject: Labor and Human Capital
subject: Social Networks
subject: Linear-in-means Model
subject: Spatial Autoregressive Model
subject: Social Norms

description: This paper studies whether conformism behavior affects individual outcomes in crime. We present a social network model of peer effects with ex-ante heterogeneous agents and show how conformism and deterrence affect criminal activities. We then bring the model to the data by using a very detailed dataset of adolescent friendship networks. A novel social network-based empirical strategy allows us to identify peer effects for different types of crimes. We find that conformity plays an important role for all crimes, especially for petty crimes. This suggests that, for juvenile crime, an effective policy should not only be measured by the possible crime reduction it implies but also by the group interactions it engenders.