cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Classification of Tripartite Entanglement with one Qubit
Creators: name: Cornelio, Marcio F.
name: Piza, A. F. R. de Toledo
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We present a method to find the decompositions of tripartite entangled pure states which are smaller than two successive Schmidt decompositions. The method becomes very simple when one of the subsystems is a qubit. In this particular case, we get a classification of states according to their decompositions. Furthermore, we also use this method to classify the entangled states that can be inter-converted through stochastic local operations and classical communication (SLOCC). More general tripartite systems are briefly discussed.
description: Revised version with a new title, a simplification in section III and added references
SPATIAL INTEGRATION OF MAIZE MARKETS IN POST-LIBERALIZED UGANDA
Creators: name: Rashid, Shahidur
name: Rashid, Shahidur
Publisher: name: Unknown
Year: 2004
Subjects: subject: Crop Production/Industries
subject: Uganda
subject: market integration
subject: causality
subject: common trend
subject: multivariate cointegration

description: Using weekly price data for two sub-periods, this paper analyzes how Ugandan maize market performed in the years following agricultural market liberalization in the early 1990’s. For each time period, the extent of integration, causality among spatial locations, and relative importance of spatial locations in price formation are examined. The extent of integration, defined as a set of markets that shares common long-run price information, and the causal relationships among markets have been tested within Johansen’s cointegration framework. The relative importance of each market locations is examined by estimating the common trend coefficients with a dynamic vector moving average model. Results indicate that, while there has been an overall improvement in spatial price responsiveness, the northern districts, which have been in a state of insurgency since 1986, continue to lack integration with major consumption markets in the central region. Causality test results show that compared to the 1993-1994-time period, representing the early years of liberalization, interdependence among markets has increased. Estimates of the common integrating trend suggest that public policies, such as price stabilization, can have desired impacts by targeting a small number of locations. These results are consistent with recently conducted household and market surveys in the country.
Gamma-Ray Burst Jet Profiles And Their Signatures
Creators: name: Graziani, C.
name: Lamb, D. Q.
name: Donaghy, T. Q.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: HETE-II and BeppoSAX have produced a sample of GRBs and XRFs with known redshifts and $E_{pk}$. This sample provides four important empirical constraints on the nature of the source jets: Log $E_{iso}$ is approximately uniformly distributed over several orders of magnitude; the inferred prompt energy Log $E_γ$ is narrowly distributed; the Amati relation holds between $E_{iso}$ and $E_{pk}$; and the Ghirlanda relation holds between $E_γ$ and $E_{pk}$. We explore the implications of these constraints for GRB jet structure during the prompt emission phase. We infer the underlying angular profiles from the first two of the above constraints assuming all jets have the same profile and total energy, and show that such ``universal jet'' models cannot satisfy both constraints. We introduce a general and efficient method for calculating relativistic emission distributions and $E_{pk}$ distributions from jets with arbitrary (smooth) angular jet profiles. We also exhibit explicit analytical formulas for emission from top-hat jets (which are not smooth). We use these methods to exhibit $E_{pk}$ and $E_{iso}$ as a function of viewing angle, for several interesting families of GRB jet profiles. We use the same methods to calculate expected frequency distributions of $E_{iso}$ and $E_γ$ for the same families of models. We then proceed to explore the behavior of universal jet models under a range of profile shapes and parameters, to map the extent to which these models can conform to the above four empirical constraints.
description: 71 page, 33 figures. Submitted to ApJ
Presentación en sesión grupal de socios de la RICAP: CoAct.Co-diseñando ciencia social ciudadana para la acción colectiva. (Presentation at RICAP's partners online group session: CoAct. Co-designing Citizen Social Science for Collective Action)
Creators: name: Actis, Guillermina
Publisher: name: Zenodo
Year: 2020
Subjects: CoAct
Citizen science
Citizen social science
Environmental justice
Collective action

description: On 24 September 2020 the annual meeting of RICAP partners (spanish acronym for Iberoamerican Network Of Participatory Science) took place. During an online group session CoAct’s project R&I action in Buenos Aires for environmental justice in the Matanza-Riachuelo Basin was presented. This action aims to promote the use of citizen science tools to achieve environmental justice. To achieve this target a data platform generated by citizens on their socio-environmental problems will be designed collaboratively. In this session the project’s progress in the context of the COVID-19 pandemic was reported. El 24 de septiembre de 2020 se realizó la reunión anual de socios de la Red Iberoamericana de Ciencia Participativa (RICAP). En el marco de una sesión grupal online se presentó la línea de acción del proyecto CoAct en Buenos Aires por la justicia ambiental en la Cuenca del Río Matanza-Riachuelo, que busca promover el uso de herramientas de ciencia ciudadana para el logro de la justicia ambiental. Para alcanzar este objetivo se diseñará de manera colaborativa una plataforma de datos generados por la ciudadanía sobre sus problemas socio-ambientales. En la presentación se expusieron los avances del proyecto en el contexto impuesto por la pandemia del COVID-19.
Pavón Cuéllar, David
Creators: name: Pavón-Cuéllar, David
Publisher: name: Zenodo
Year: 2020
Subjects: ¨David Pavón-Cuéllar
Marxismo
Psicoanálisis

description: Autobiografía del autor escrita por invitación para el Diccionario de autobiografías intelectuales de la Red de Pensamiento Alternativo dirigido por Hugo Biagini y publicado por la Universidad de Lanús.
Title Area density of localization-entropy I: the case of wedge-localization
Creators: name: Schroer, Bert
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Using an appropriatly formulated holographic lightfront projection, we derive an area law for the localization-entropy caused by vacuum polarization on the horizon of a wedge region. Its area density has a simple kinematic relation to the volume extensive heat bath entropy of the lightfront algebra. Apart from a change of parametrization the infinite lighlike length contribution to the lightfront volume factor corresponds to the short-distance divergence of the area density of the localization entropy. This correspondence is a consequence of the conformal invariance of the lightfront holography combined with the well-known fact that in conformality relates short to long distances. In the explicit calculation of the strength factor we use the temperature duality relation of rational chiral theories whose derivation will be briefly reviewed. We comment on the potential relevance for the understanding of Black hole entropy.
description: This version will be published in Class. Quant. Grav. Some arguments and computations are presented in more detail. 29 pages
A Light Heterogeneous Graph Collaborative Filtering Model using Textual Information
Creators: name: Wang, Chaoyang
name: Guo, Zhiqiang
name: Li, Guohui
name: Li, Jianjun
name: Pan, Peng
name: Liu, Ke
Publisher: name: arXiv
Year: 2020
Subjects: subject: Information Retrieval (cs.IR)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Due to the development of graph neural networks, graph-based representation learning methods have made great progress in recommender systems. However, data sparsity is still a challenging problem that most graph-based recommendation methods are confronted with. Recent works try to address this problem by utilizing side information. In this paper, we exploit the relevant and easily accessible textual information by advanced natural language processing (NLP) models and propose a light RGCN-based (RGCN, relational graph convolutional network) collaborative filtering method on heterogeneous graphs. Specifically, to incorporate rich textual knowledge, we utilize a pre-trained NLP model to initialize the embeddings of text nodes. Afterward, by performing a simplified RGCN-based node information propagation on the constructed heterogeneous graph, the embeddings of users and items can be adjusted with textual knowledge, which effectively alleviates the negative effects of data sparsity. Moreover, the matching function used by most graph-based representation learning methods is the inner product, which is not appropriate for the obtained embeddings that contain complex semantics. We design a predictive network that combines graph-based representation learning with neural matching function learning, and demonstrate that this architecture can bring a significant performance improvement. Extensive experiments are conducted on three publicly available datasets, and the results verify the superior performance of our method over several baselines.
description: Accepted by Knowledge-Based Systems
TESS photometry of extreme helium stars PV Tel and V821 Cen
Creators: name: Jeffery, C. Simon
name: Barentsen, Geert
name: Handler, Gerald
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: PV Tel variables are extreme helium (EHe) stars known to be intrinsic light and velocity variable on characteristic timescales 0.1 - 2 d. With two exceptions, they are best described as irregular. Light curves have invariably been obtained from single-site terrestrial observatories. We present TESS observations of two bright EHe stars, Popper's star (V821 Cen) and Thackeray's star (PV Tel). PV Tel is variable on timescales previously reported. V821 Cen is proven to be variable for the first time. Neither light curve shows any evidence of underlying regularity. Implications are considered.
description: 4 pages, 2 figures
Stimulated wave of polarization in 1D Ising chain
Creators: name: Lee, Jae-Seung
name: Khitrin, A. K.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: It is demonstrated that in one-dimensional Ising chain with nearest-neighbor interactions, irradiated by a weak resonant transverse field, a stimulated wave of flipped spins can be triggered by a flip of a single spin. This analytically solvable model illustrates mechanisms of quantum amplification and quantum measurement.
description: 14 pages, 3 figures
Power fluctuations in a finite-time quantum Carnot engine
Creators: name: Denzler, Tobias
name: Lutz, Eric
Publisher: name: arXiv
Year: 2020
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Stability is an important property of small thermal machines with fluctuating power output. We here consider a finite-time quantum Carnot engine based on a degenerate multilevel system and study the influence of its finite Hilbert space structure on its stability. We optimize in particular its relative work fluctuations with respect to level degeneracy and level number. We find that its optimal performance may surpass those of nondegenerate two-level engines or harmonic oscillator motors. Our results show how to realize high-performance, high-stability cyclic quantum heat engines.
description: 8 pages, 3 figures
Infrared scattering rate of overdoped Tl$_{2}$Ba$_{2}$CuO$_{6+δ}$
Creators: name: Ma, Y. C.
name: Wang, N. L.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present in-plane optical study on Tl$_{2}$Ba$_{2}$CuO$_{6+δ}$ single crystals with substantially different $T_c$. The study reveals that the overdoping does not lead to a further increase of the carrier density but a decrease of scattering rate. The most significant change occurs at low temperature and in the low frequency. A characteristic spectral feature, seen most clearly for the optimally doped sample and commonly ascribed to the mode coupling effect, weakens with doping and disappears in the heavily overdoped sample. Meanwhile, the optical scattering rate evolves from a linear-$ω$ dependence to an upward curvature lineshape. Both the temperature and frequency dependence of the scattering rate can be described by a power law relation. We elaborate that the overall decrease of the optical scattering rate originates from the increase of both the quasiparticle life time and the Fermi velocity near the ($π$,0) region in the Fermi surface.
description: 7 figures, Phys. Rev. B (accepted), the pdf file of previous (submission) version could not be generated properly
PURULENT-INFLAMMATORY DISEASES OF THE RETROPERITONEAL SPACE: DIVERSITY AND METHODS OF SURGICAL TREATMENT
Creators: name: Akromov, Iskandar
name: Kuchkarov, Akmal
Publisher: name: Zenodo
Year: 2024

description: A retroperitoneal abscess is a limited accumulation of pus located between the posterior leaf of the peritoneum and the intraperitoneal fascia. Ulcers can be single, reaching significant amounts at the same time, or multiple. Diagnosis of the latter is difficult due to the small size of the formations and the erased clinical picture [3]. Abscesses can form as a result of injuries, surgical intervention, perforation of the organ canopy and metastasis of infection from neighboring structures. Ulcers appear in 0.8% of cases after elective abdominal surgery, and in 1.5% after emergency surgery. The disease occurs mainly in people aged 20-40 years [4,7].
Participatory knowledge production and their transformative potential for environmental justice: the case of Matanza-Riachuelo river basin (Buenos Aires, Argentina)
Creators: name: Actis, Guillermina
name: Swistun, Débora
name: Arza, Valeria
Publisher: name: Zenodo
Year: 2020
Subjects: CoAct
Citizen social science
Participation
Knowledge Coalition

description: “Participatory knowledge production and their transformative potential for environmental justice: the case of Matanza-Riachuelo river basin (Buenos Aires, Argentina)“ is the title of this presentation given during ECSA Conference 2020 in the framework of Session 14 on Citizen Social Science. The case of study is the CoAct R&I Action in Buenos Aires regarding environmental justice in the Riachuelo-Matanza basin. The presentation focuses on the building of the project´s knowledge coalition and reviews previous participatory experiences of grassroots organizations and NGO’s initiatives as well.
Interface Equations for Capillary Rise in Random Environment
Creators: name: Laurila, T.
name: Tong, C.
name: Majaniemi, S.
name: Ala-Nissila, T.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We consider the influence of quenched noise upon interface dynamics in 2D and 3D capillary rise with rough walls by using phase-field approach, where the local conservation of mass in the bulk is explicitly included. In the 2D case the disorder is assumed to be in the effective mobility coefficient, while in the 3D case we explicitly consider the influence of locally fluctuating geometry along a solid wall using a generalized curvilinear coordinate transformation. To obtain the equations of motion for meniscus and contact lines, we develop a systematic projection formalism which allows inclusion of disorder. Using this formalism, we derive linearized equations of motion for the meniscus and contact line variables, which become local in the Fourier space representation. These dispersion relations contain effective noise that is linearly proportional to the velocity. The deterministic parts of our dispersion relations agree with results obtained from other similar studies in the proper limits. However, the forms of the noise terms derived here are quantitatively different from the other studies.
Pattern formation in a stochastic model of cancer growth
Creators: name: Ochab-Marcinek, Anna
Publisher: name: arXiv
Year: 2005
Subjects: subject: Cell Behavior (q-bio.CB)
subject: FOS: Biological sciences

description: We investigate noise-induced pattern formation in a model of cancer growth based on Michaelis-Menten kinetics, subject to additive and multiplicative noises. We analyse stability properties of the system and discuss the role of diffusion and noises in the system's dynamics. We find that random dichotomous fluctuations in the immune response intensity along with Gaussian environmental noise lead to emergence of a spatial pattern of two phases, in which cancer cells, or, respectively, immune cells predominate.
description: 17 pages, 15 figures
Casimir Effects: an Optical Approach II. Local Observables and Thermal Corrections
Creators: name: Scardicchio, A.
name: Jaffe, R. L.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We recently proposed a new approach to the Casimir effect based on classical ray optics (the "optical approximation"). In this paper we show how to use it to calculate the local observables of the field theory. In particular we study the energy-momentum tensor and the Casimir pressure. We work three examples in detail: parallel plates, the Casimir pendulum and a sphere opposite a plate. We also show how to calculate thermal corrections, proving that the high temperature `classical limit' is indeed valid for any smooth geometry.
description: 35 pages, 7 figures
Basal-Plane Magnetic Anisotropies of High-kappa d-Wave Superconductors in a Mixed State: A Quasiclassical Approach
Creators: name: Adachi, H.
name: Miranović, P.
name: Ichioka, M.
name: Machida, K.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study the basal-plane anisotropies of reversible magnetization and torque in a mixed state of layered d-wave superconductors based on the quasiclassical version of the BCS-Gor'kov theory. Both the longitudinal magnetization ($M_L$) and torque ($τ$) show fourfold oscillations as a function of the field angle $χ$. The relationship between the node position and the oscillatory patterns shown by $M_L$ and $τ$ is clarified. It is also shown that the sign of the $τ(χ)$-oscillation does not change between $H_{c1}$ and $H_{c2}$, while the sign of the $M_L (χ)$-oscillation changes. The newly obtained result for $τ$ indicates that the torque experiment can allow us to detect the in-plane anisotropies of $H_{c2}$ even in a material with strong fluctuations such as cuprate or organic superconductors, where the $H_{c2}$ itself cannot be determined experimentally.
description: 10 pages, 9 figures
Effects of Noise on Entropy Evolution
Creators: name: Mackey, Michael C.
name: Tyran-Kaminska, Marta
Publisher: name: arXiv
Year: 2005
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study the convergence properties of the conditional (Kullback-Leibler) entropy in stochastic systems. We have proved very general results showing that asymptotic stability is a necessary and sufficient condition for the monotone convergence of the conditional entropy to its maximal value of zero. Additionally we have made specific calculations of the rate of convergence of this entropy to zero in a one-dimensional situations, illustrated by Ornstein-Uhlenbeck and Rayleigh processes, higher dimensional situations, and a two dimensional Ornstein-Uhlenbeck process with a stochastically perturbed harmonic oscillator and colored noise as examples. We also apply our general results to the problem of conditional entropy convergence in the presence of dichotomous noise. In both the single dimensional and multidimensional cases we are to show that the convergence of the conditional entropy to zero is monotone and at least exponential. In the specific cases of the Ornstein-Uhlenbeck and Rayleigh processes as well as the stochastically perturbed harmonic oscillator and colored noise examples, we have the rather surprising result that the rate of convergence of the entropy to zero is independent of the noise amplitude.
description: 23 pages
LAND AND ASSET SIZE, STRUCTURE AND DISTRIBUTION AND THE LINKS TO INCOME IN THREE DRYLANDS
Creators: name: Lipton, Michael
name: Eastwood, Robert
name: Kirsten, Johann F.
name: Lipton, Michael
name: Eastwood, Robert
name: Kirsten, Johann F.
Publisher: name: Unknown
Year: 2003
Subjects: International Development

description: At a late stage in preparing this work, we felt - responding to the view of all partners - that, before analyzing the consequences of asset situations for fertility, migration or environment, we should present, and to some extent explain, some facts about the size, composition, and distribution of assets for the three countries. This paper presents some general contextual evidence, and some main results for South Africa. Work is in progress in the India data, and will be undertaken later for Botswana.
NEW WATER POLICY, IRRIGATION MANAGEMENT TRANSFER AND SMALLHOLDING IRRIGATION SCHEMES IN SOUTH AFRICA: INSTITUTIONAL CHALLENGES
Creators: name: Perret, Sylvain R.
name: Perret, Sylvain R.
Publisher: name: Unknown
Year: 2001
Subjects: Resource /Energy Economics and Policy

description: This paper briefly reviews the situation of smallholding irrigation schemes -SIS- in previously disadvantaged rural areas of South Africa. It then analyses the implication of the new National Water Act of 1998 on those schemes, with regard to the IMT process. An analysis of water rights related issues is proposed. It highlights a number of contradictions, uncertainties and possible threats which may hinder further development, and sustainable IMT in SIS.
Band Structure and Quantum Conductance of Nanostructures from Maximally-Localized Wannier Functions: The Case of Functionalized Carbon Nanotubes
Creators: name: Lee, Young-Su
name: Nardelli, Marco Buongiorno
name: Marzari, Nicola
Publisher: name: arXiv
Year: 2005
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We have combined large-scale, $Γ$-point electronic-structure calculations with the maximally-localized Wannier functions approach to calculate efficiently the band structure and the quantum conductance of complex systems containing thousands of atoms while maintaining full first-principles accuracy. We have applied this approach to study covalent functionalizations in metallic single-walled carbon nanotubes. We find that the band structure around the Fermi energy is much less dependent on the chemical nature of the ligands than on the $sp^3$ functionalization pattern disrupting the conjugation network. Common aryl functionalizations are more stable when paired with saturating hydrogens; even when paired, they still act as strong scattering centers that degrade the ballistic conductance of the nanotubes already at low degrees of coverage.
description: To be published in Phys. Rev. Lett
Metastable liquid-liquid coexistence and density anomalies in a core-softened fluid
Creators: name: Gibson, Helen M.
name: Wilding, Nigel B.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Linearly-sloped or `ramp' potentials belong to a class of core-softened models which possess a liquid-liquid critical point (LLCP) in addition to the usual liquid-gas critical point. Furthermore they exhibit thermodynamic anomalies in the density and compressibility, the nature of which may be akin to those occurring in water. Previous simulation studies of ramp potentials have focused on just one functional form, for which the LLCP is thermodynamically stable. In this work we construct a series of ramp potentials, which interpolate between this previously studied form and a ramp-based approximation to the Lennard-Jones (LJ) potential. By means of Monte Carlo simulation, we locate the LLCP, the first order high density liquid (HDL)-low density liquid (LDL) coexistence line, and the line of density maxima for a selection of potentials in the series. We observe that as the LJ limit is approached, the LLCP becomes metastable with respect to freezing into a hexagonal close packed crystalline solid. The qualitative nature of the phase behaviour in this regime shows a remarkable resemblance to that seen in simulation studies of accurate water models. Specifically, the density of the liquid phase exceeds that of the solid; the gradient of the metastable LDL-HDL line is negative in the pressure (p)-temperature (T) plane; while the line of density maxima in the p-T plane has a shape similar to that seen in water and extends well into the {\em stable} liquid region of the phase diagram. As such, our results lend weight to the `second critical point' hypothesis as an explanation for the anomalous behaviour of water.
description: 7 pages, 8 figures
TESS photometry of helium-rich hot subdwarfs: r modes in BD+37 442 and BD+37 1977
Creators: name: Jeffery, C. Simon
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: TESS photometry of the extremely helium-rich hot subdwarfs BD+37 442 and BD+37 1977 demonstrates multi-periodic low-amplitude variability with principal periods of 0.56 and 1.14 d, respectively, and with both first and second harmonics present. The lightcurves are not perfectly regular, implying additional periodic and/or non-periodic content. Possible causes are examined, including the binary hypothesis originally introduced to explain X-ray observations, differentially rotating surface inhomogeneities, and pulsations. If the principal photometric periods correspond to the rotation periods, the stars are rotating at approximately 0.7 and 0.3 x breakup, respectively. Surface Rossby waves (r modes) therefore provide the most likely solution.
description: MNRAS accepted, 6 pages, 3 figures
MATCHING POLICIES ON RURAL DEVELOPMENT AND LOCAL GOVERNANCE IN SOUTH AFRICA: RECENT HISTORY, PRINCIPLES, AND CURRENT CHALLENGES
Creators: name: Perret, Sylvain R.
name: Perret, Sylvain R.
Publisher: name: Unknown
Year: 2004
Subjects: Community/Rural/Urban Development
Political Economy

description: The paper discusses the link between local governance and rural development in democratic South Africa. It underlines several issues and challenges facing the government's willingness to position local municipalities as the key providers and promoters of development in rural areas. The paper first presents two parallel policy streams that took place since 1994. On the one hand, local government has been gradually established and strengthened, as the third constitutional sphere of governance, in line with an overall decentralization process. On the other hand, rural development has taken a growing place into political discourses from 1994 onwards, and has been promoted or implemented through various policies, legislations and programmes, which has often been conceived and managed centrally, at the national and/or provincial levels. The paper then describes the current situation in terms of linkages between local government and rural development initiatives. It is argued that, in spite of a closer link and integration between overall policies and approaches to rural development (ISRDP) and local government planning tools (IDPs), a series of issues and challenges are still hindering efficient delivery and services towards rural areas and their development. Among other issues, the paper identifies and discusses (1) contradicting approaches that are still combined de facto (liberalism vs. welfarism), (2) the lack of actual participation and the weakness of CSOs in rural South Africa, (3) revenue issues at the rural municipal level, (4) the discussable role of district municipalities, (5) a hidden supply-driven agenda by line departments, along with poor co-ordination among them, and (6) long-living myths about the potential of certain areas, or the possible role of agriculture. The paper concludes with some recommendations, especially stressing the possible role of academics to help and support decision-makers and development operators.
Self-Similar Evaporation of a Rigidly-Rotating Cosmic String Loop
Creators: name: Anderson, Malcolm
Publisher: name: arXiv
Year: 2005
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The gravitational back-reaction on a certain type of rigidly-rotating cosmic string loop, first discovered by Allen, Casper and Ottewill, is studied at the level of the weak-field approximation. The near-field metric perturbations are calculated and used to construct the self-acceleration vector of the loop. Although the acceleration vector is divergent at the two kink points on the loop, its net effect on the trajectory over a single oscillation period turns out to be finite. The net back-reaction on the loop over a single period is calculated using a method due to Quashnock and Spergel, and is shown to induce a uniform shrinkage of the loop while preserving its original shape. The loop therefore evolves by self-similar evaporation.
description: 41 pages, 5 figures. Accepted for publication in Classical and Quantum Gravity
THE FINANCIAL POSITION OF SOUTH AFRICAN AGRICULTURE
Creators: name: Coetzee, Gerhard K.
name: Meyser, F.
name: Adam, H.
name: Coetzee, Gerhard K.
name: Meyser, F.
name: Adam, H.
Publisher: name: Unknown
Year: 2002
Subjects: Agricultural Finance

description: The agricultural sector in South Africa is subjected to major changes due to a simultaneous influence of external and internal forces after the political changes in South Africa and its opening to the rest of the world. The external forces are mostly linked to increasing globalisation including a changing internal trade regime. Internal forces have to do with the liberalisation of agriculture and for example the changing role of government with respect to the provision of financial services. This paper indicates the effect of these influences on the financial position of the farming sector and provides a point of departure for the monitoring of future trends. It further indicates the strategies followed by farmers to counter the negative trends experienced. It is a component of a much broader study on the agricultural finance situation in South Africa.
QCD Radiation in the Production of High s-hat Final States
Creators: name: Skands, Peter
name: Plehn, Tilman
name: Rainwater, David
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In the production of very heavy final states - high Mandelstam s-hat - extra QCD radiation can play a significant role. By comparing several different parton shower approximations to results obtained with fixed-order perturbation theory, we quantify the degree to which these approaches agree (or disagree), focussing on initial state radiation above pT = 50 GeV, for top pair production at the Tevatron and at the LHC, and for SUSY pair production at the LHC. Special attention is paid to ambiguities associated with the choice of the maximum value of the ordering variable in parton shower models.
description: Invited talk at 2005 International Linear Collider Physics and Detector Workshop and Second ILC Accelerator Workshop, Snowmass, CO (Snowmass05), 5 pages, LaTeX, 3 eps figures
ARE SOUTH AFRICAN CO-OPERATIVES CREATING VALUE
Creators: name: Hall, John H.
name: Geyser, J.M.
name: Hall, John H.
name: Geyser, J.M.
Publisher: name: Unknown
Year: 2003
Subjects: subject: Agribusiness
subject: economic value added
subject: agricultural cooperatives
subject: value
subject: economic model

description: This article examines the use of Economic Value Added (EVA) as a performance measure that South African wine co-operatives can use to determine whether value has been created for members. A detailed explanation of EVA is given, and the components of EVA are calculated. The EVA's of a number of co-operatives have been calculated and analysed. In addition the EVA of specific types of co-operatives indicate that the fruit and vegetable sector is a constant value creator. It is clear that in order to create value, the rate of return on invested capital must be greater than the cost of capital. Certain co-operatives and types of co-operatives provided the blue print for this.
Dataset from: Predicting early-onset COPD risk in adults aged 20-50 using electronic health records and machine learning.
Creators: name: Ailurus Biotechnology Co., Ltd.
Publisher: name: Zenodo
Year: 2024

description: Project Name: COPD Risk Prediction and Assessment

This project aims to analyze samples from the UK Biobank dataset related to Chronic Obstructive Pulmonary Disease (COPD). The project involves careful sample selection, integration of personal health information and blood biochemical indicators, grouping of positive and negative samples, Genome-Wide Association Study (GWAS) analysis, multiple machine learning (ML) model development based on these features, evaluation of model performance, and graphical representation of the study results.

Workflow and Process:

Sample Selection and Preparation: Careful selection of COPD-related samples from the UK Biobank ensuring quality and representativeness. Integration of personal health information and blood biochemical indicators to construct feature sets.

Related Files/Directories:

S3_label_select.csv: CSV file with selected labels.

feature_info: Directory containing feature information.

Positive and Negative Sample Grouping and GWAS Analysis: Grouping of selected samples into positive and negative categories followed by GWAS analysis to explore genetic variations associated with COPD risk.

Related Files/Directories:

gwas: Directory containing GWAS-related files.

GWAS_plot: Directory containing GWAS plots.

Machine Learning Model Development: Utilization of various ML models like logistic regression, random forest, neural networks, etc., based on the selected features to predict COPD risk.

Related Files/Directories:

code: Directory containing code files for ML model development.

Model Performance Evaluation: Assessment of model performance and comparative analysis to examine predictive capabilities and stability.

Related Files/Directories:

S2_traintest_id.RData: RData file with training and testing identifiers.

S4_lm_res.RData: RData file with linear regression results.

S5_model_res.zip: Compressed file containing model results.

Result Visualization and Validation: Graphical representation of results including GWAS plots, model evaluation outcomes, etc., for demonstrating the reliability and effectiveness of the research.

Related Files/Directories:

paper_chart: Directory containing charts and figures for the research paper.

paper_files: Directory containing files related to the research paper.
Análise lacaniana de discurso: entre a psicologia crítica e o impaciente anseio do acontecimento
Creators: name: Pavón-Cuéllar, David
Publisher: name: Zenodo
Year: 2019
Subjects: Análise Lacaniana de Discurso
Lacanian Discourse Analysis
Critical Psychology
Psicología crítica

description: Revisión histórica del campo emergente del análisis lacaniano de discurso y reflexión sobre sus vínculos con la investigación psicosocial, la psicología crítica y la acción política revolucionaria
Testing the Mutual Consistency of the Pantheon and SDSS/eBOSS BAO Data Sets with Gaussian Processes
Creators: name: Keeley, Ryan E.
name: Shafieloo, Arman
name: Zhao, Gong-Bo
name: Vazquez, Jose Alberto
name: Koo, Hanwool
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We test the mutual consistency between the baryon acoustic oscillation measurements from the eBOSS SDSS final release, as well as the Pantheon supernova compilation in a model independent fashion using Gaussian process regression. We also test their joint consistency with the $Λ$CDM model, also in a model independent fashion. We also use Gaussian process regression to reconstruct the expansion history that is preferred by these two datasets. While this methodology finds no significant preference for model flexibility beyond $Λ$CDM, we are able to generate a number of reconstructed expansion histories that fit the data better than the best-fit $Λ$CDM model. These example expansion histories may point the way towards modifications to $Λ$CDM. We also constrain the parameters $Ω_k$ and $H_0r_d$ both with $Λ$CDM and with Gaussian process regression. We find that $H_0r_d =10030 \pm 130$ km/s and $Ω_k = 0.05 \pm 0.10$ for $Λ$CDM and that $H_0r_d = 10040 \pm 140$ km/s and $Ω_k = 0.02 \pm 0.20$ for the Gaussian process case.
description: 7 pages, 3 figures
Hubble Space Telescope Imaging of Globular Cluster Candidates in Low Surface Brightness Dwarf Galaxies
Creators: name: Sharina, Margarita E.
name: Puzia, Thomas H.
name: Makarov, Dmitry I.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Fifty-seven nearby low surface brightness dwarf galaxies were searched for globular cluster candidates (GCCs) using Hubble Space Telescope WFPC2 imaging in V and I. The sample consists of 18 dwarf spheroidal (dSph), 36 irregular (dIrr), and 3 "transition" type (dIrr/dSph) galaxies with angular sizes less than 3.7 kpc situated at distances 2-6 Mpc in the field and in the nearby groups: M81, Centaurus A, Sculptor, Canes Venatici I cloud. We find that ~50% of dSph, dIrr/dSph, and dIrr galaxies contain GCCs. The fraction of GCCs located near the center of dwarf spheroidal galaxies is >2 times higher than that for dIrrs. The mean integral color of GCCs in dSphs, V-I = 1.04+/-0.16 mag, coincides with the corresponding value for Galactic globular clusters and is similar to the blue globular cluster sub-populations in massive early-type galaxies. The color distribution for GCCs in dIrrs shows a clear bimodality with peaks near V-I = 0.5 and 1.0 mag. Blue GCCs are presumably young with ages t < 1 Gyr, while the red GCC population is likely to be older. The detected GCCs have absolute visual magnitudes between M_V = -10 and -5 mag. We find indications for an excess population of faint GCCs with M_V > -6.5 mag in both dSph and dIrr galaxies, reminiscent of excess populations of faint globular clusters in nearby Local Group spiral galaxies. The measurement of structural parameters using King-profile fitting reveals that most GCCs have structural parameters similar to extended outer halo globular clusters in the Milky Way and M31, as well as the recently discovered population of "faint fuzzy" clusters in nearby lenticular galaxies.
description: A&A accepted, 17 pages
Chemical Composition of Two H II Regions in NGC 6822 Based on VLT Spectroscopy
Creators: name: Peimbert, Antonio
name: Peimbert, Manuel
name: Ruiz, Maria Teresa
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present long slit spectrophotometry of regions V and X of the local group irregular galaxy NGC 6822. The data consist of VLT FORS observations in the 3450 to 7500 A range. We have obtained electron temperatures and densities using different line intensity ratios. We have derived the He, C, and O abundances relative to H based on recombination lines, the abundance ratios among these elements are almost independent of the temperature structure of the nebulae. We have also determined the N, O, Ne, S, Cl, and Ar abundances based on collisionally excited lines, the ratios of these abundances relative to that of H depend strongly on the temperature structure of the nebulae. The chemical composition of NGC 6822 V is compared with those of the Sun, the Orion nebula, NGC 346 in the SMC, and 30 Doradus in the LMC. The O/H value derived from recombination lines is in good agreement with the value derived by Venn et al. (2001) from two A type supergiants in NGC 6822.
description: 36 pages, Accepted for publication in the Astrophysical Journal
THE STRUCTURE OF SOUTH AFRICAN MILK PRODUCTION TECHNOLOGY: A PARAMETRIC APPROACH TO SUPPLY ANALYSIS
Creators: name: Beyers, Lindie
name: Hassan, Rashid M.
name: Beyers, Lindie
name: Hassan, Rashid M.
Publisher: name: Unknown
Year: 2000
Subjects: Livestock Production/Industries

description: A parametric approach was followed in this study to analyse milk production and supply systems based on farm level production cost data from a cross-section of dairy farms in South Africa for the 1997/1998 production year. Both single equation and system estimation techniques were applied to Normalised Quadratic, Normalised Translog and standard Translog specifications of the profit and derived output supply and input demand functions. Estimated functions were evaluated for adherence to structural properties. Results showed that convexity of the profit function in all prices holds in South African milk production. Uncompensated and compensated price elasticities of supply and demand were calculated. The results indicated that milk production and livestock trading activities are complements in the production activities of the observed multi-input, multi-output dairy farms. Both activities were intensive in the use of purchased and self-produced feed inputs, with a higher intensity in purchased feed use. The variable inputs are gross complements in the long-run and net substitutes in the short term. The long-term expansion effects overshadow short-term substitution between inputs. The results from this study suggest that dairy producers in South Africa are rational profit maximisers who use resources efficiently to the point where the marginal returns are zero. They allocate bought and self-produced feed components as substitutes in the short-run but treat both inputs as complements in the long-run.
Rydberg Noisy-Dressing and applications in making soliton-molecules and droplet quasi-crystals
Creators: name: Khazali, Mohammadsadegh
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Atomic and Molecular Clusters (physics.atm-clus)
subject: FOS: Physical sciences

description: The current advances in the field of ultra-cold atoms and atomic traps recall new controllable long-range interactions. These interactions are expected to extend the range of realizable quantum algorithms as well as providing new control mechanisms for the new types of quantum matters. This article presents special inter-atomic interactions between Rydberg-dressed atoms by manipulating lasers' line-width. The new interaction features a hybrid spatial profile containing plateaus and Gaussian peaks. Combined with dynamic individual control over the sign and strength of these interaction elements, the Rydberg noisy-dressing (RnD) scheme provides a valuable interaction toolbox for quantum technology. As an example, RnD's application in making stable gigantic 3D soliton molecules and in the formation of quasi-periodic droplet-crystals are discussed.
PRICE AND PRICE RISK DYNAMICS IN BARGE AND OCEAN FREIGHT MARKETS AND THE EFFECTS ON COMMODITY TRADING
Creators: name: Haigh, Michael S.
name: Bryant, Henry L.
name: Haigh, Michael S.
name: Bryant, Henry L.
Publisher: name: Unknown
Year: 2000
Subjects: subject: International Relations/Trade
subject: Barge and ocean freight prices
subject: futures contracts
subject: Multivariate GARCH-Models
subject: Price volatility

description: The effects of volatility of barge and ocean freight prices on prices throughout the international grain-marketing channel are analyzed using a Multivariate GARCH-M model. The model is used to infer the extent to which transportation price risk affects the level of international grain prices. Results indicate that both barge and ocean price volatility influence grain prices, but barge price volatility tends to have a greater impact on grain prices than that arising from ocean price volatility. The lack of a futures contract for barge rates may be partially responsible for its significant influence on grain price levels.
Matching theorems for systems of a finitely generated Coxeter group
Creators: name: Mihalik, Michael
name: Ratcliffe, John
name: Tschantz, Steven
Publisher: name: arXiv
Year: 2005
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 20F55

description: In this paper we prove a series of matching theorems for two sets of Coxeter generators of a finitely generated Coxeter group that identify common features of the two sets of generators. As an application, we describe an algorithm for finding a set of Coxeter generators of maximum rank for a finitely generated Coxeter group.
description: This paper replaces our earlier paper "On the isomorphism problem for finitely generated Coxeter groups. I, Basic matching". 49 pages. Sections 7-10 are new
Baker domains for Newton's method
Creators: name: Bergweiler, Walter
name: Drasin, D.
name: Langley, J. K.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Complex Variables (math.CV)
subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 30D05, 37F10, 65H05

description: We show that there exists an entire function without finite asymptotic values for which the associated Newton function tends to infinity in some invariant domain. The question whether such a function exists had been raised by Douady.
description: 8 pages
Classical limit of master equation for harmonic oscillator coupled to oscillator bath with separable initial conditions
Creators: name: Banerjee, Subhashish
name: Dhar, Abhishek
Publisher: name: arXiv
Year: 2005
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The equation for the Wigner function describing the reduced dynamics of a single harmonic oscillator, coupled to an oscillator bath, was obtained by Karrlein and Grabert [Phys. Rev. E, vol. 55, 153 (1997)]. It was shown that for some special correlated initial conditions the equation reduces, in the classical limit, to the corresponding classical Fokker-Planck equation obtained by Adelman [J. Chem Phys., vol. 64, 124 (1976)]. However for separable initial conditions the Adelman equations were not recovered. We resolve this problem by showing that, for separable initial conditions, the classical Langevin equation obtained from the oscillator bath model is somewhat different from the one considered by Adelman. We obtain the corresponding Fokker-Planck equation and show that it exactly matches the classical limit of the equation for the Wigner function obtained from the master equation for separable initial conditions. We also discuss why the special correlated initial conditions correspond to Adelman's solution.
description: 12 pages