cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
A produção de flores no estado do Ceará: aspectos tecnológicos, econômicos e competitivos
Creators: name: Oliveira Junior, Jose Nilo De
name: Khan, Ahmad Saeed
name: Silva, Lucia Maria Ramos
name: Oliveira Junior, Jose Nilo De
name: Khan, Ahmad Saeed
name: Silva, Lucia Maria Ramos
Publisher: name: Unknown
Year: 2003
Subjects: subject: Agribusiness
subject: Floricultura
subject: Rentabilidade
subject: Tecnologia
subject: Ceará

description: Este estudo procurou analisar a floricultura no Estado do Ceará, enfocando a produção de helicônias nos principais municípios produtores do Estado, mais precisamente avaliando o nível tecnológico empregado na produção e a rentabilidade da atividade e competitividade, em termos de eficiência dos produtores. A pesquisa realizou-se por meio de coleta de dados primários obtidos de entrevistas diretas com produtores nos municípios que compõem as regiões metropolitana e maciço de Baturité, de acordo com o cadastro da Secretaria de Agricultura Irrigada-SEAGRI, no período de outubro de 2002. Na avaliação do nível tecnológico dividiu-se o sistema de produção de helicônia em sete tecnologias: propagação, uso dos solos, adubação, tratos culturais, cuidados fitossanitários, gestão, colheita e pós-colheita. Daí, foram desenvolvidos índices tecnológicos para cada uma separadamente e para o conjunto delas, com base na respectiva tecnologia recomendada. Na avaliação da rentabilidade utilizou-se a metodologia do Sistema Integrado de Custos Agropecuários – CUSTAGRI e, na análise da competitividade, utilizaram-se os indicadores de eficiência como preços e custos e índice de lucratividade. Os principais resultados obtidos mostram que o nível tecnológico dos produtores de helicônia é considerado bom; a tecnologia de uso dos solos apresenta melhores índices; enquanto na tecnologia de cuidados fitossanitários foram encontrados os mais baixos índices. No que se refere à rentabilidade, a produção de helicônia é uma atividade rentável, visto que se constitui de baixos custos e pode chegar a altos índices de lucratividade.
Study of the single neutral top-pion production process at $γγ$ collider
Creators: name: Wang, Xuelei
name: Wang, Xiaoxue
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: $γγ\to Π_t^0$ is the major production mechanism of neutral top-pion at the linear colliders. In this paper, we calculate the cross section of the process $γγ\to Π^0_t$ and discuss the potential to observe the neutral top-pion via its various decay modes at the planned ILC. The study show that, among the various neutral top-pion production processes at the linear colliders, the cross section of $γγ\to Π_t^0$ is the largest one which can reach the level of $10^1-10^2$ fb. Due to the existence of the tree-level flavor-changing coupling $Π_t^0 t\bar{c}$, $γγ\to Π_t^0 \to t\bar{c}$ can provide enough number of typical signals to identify the neutral top-pion with the clean SM background. Therefore, the process $γγ\to Π_t^0$ play an important role in searching for the neutral top-pion and test the TC2 model.
description: 16 pages, 5 figures
Impactos do programa de fomento à cafeicultura no pequeno produtor do município de Viçosa - MG: uma análise financeira sob condições de risco
Creators: name: Ferreira Junior, Silvio
name: Baptista, Antonio Jose Medina Dos Santos
name: Ferreira Junior, Silvio
name: Baptista, Antonio Jose Medina Dos Santos
Publisher: name: Unknown
Year: 2003
Subjects: subject: Risk and Uncertainty
subject: Cafeicultura
subject: Rentabilidade
subject: Análise de risco

description: Diante da importância socioeconômica da cafeicultura para o município de Viçosa, a Secretaria Municipal de Agricultura e Meio Ambiente (SEAMA) lançou, em 1998, o “Programa Municipal de Fomento à Cafeicultura” (ProCafé). O presente trabalho procurou mensurar e analisar os benefícios financeiros desse programa para o pequeno produtor local, com o intuito de fornecer subsídios às autoridades e aos produtores efetivos e potenciais no que concerne aos riscos e oportunidades inerentes ao investimento. Os indicadores de viabilidade e a análise de sensibilidade mostraram, claramente, que é financeiramente viável investir na atividade. O programa ProCafé proporciona benefícios financeiros adicionais, melhorando significativamente a viabilidade e reduzindo substancialmente os riscos do investimento. No entanto, sugere-se o avanço do programa ProCafé como condição necessária para estimular a melhoria da competitividade e reduzir os riscos inerentes à atividade cafeeira.
Automatic Differentiation in ROOT
Creators: name: Vassilev, Vassil
name: Efremov, Aleksandr
name: Shadura, Oksana
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mathematical Software (cs.MS)
subject: Computation and Language (cs.CL)
subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: In mathematics and computer algebra, automatic differentiation (AD) is a set of techniques to evaluate the derivative of a function specified by a computer program. AD exploits the fact that every computer program, no matter how complicated, executes a sequence of elementary arithmetic operations (addition, subtraction, multiplication, division, etc.), elementary functions (exp, log, sin, cos, etc.) and control flow statements. AD takes source code of a function as input and produces source code of the derived function. By applying the chain rule repeatedly to these operations, derivatives of arbitrary order can be computed automatically, accurately to working precision, and using at most a small constant factor more arithmetic operations than the original program. This paper presents AD techniques available in ROOT, supported by Cling, to produce derivatives of arbitrary C/C++ functions through implementing source code transformation and employing the chain rule of differential calculus in both forward mode and reverse mode. We explain its current integration for gradient computation in TFormula. We demonstrate the correctness and performance improvements in ROOT's fitting algorithms.
description: Submitted as a proceeding for CHEP 2019
Inventário macroeconômico do governo FHC
Creators: name: Silva, Jose Maria Alves Da
name: Silva, Jose Maria Alves Da
Publisher: name: Unknown
Year: 2003
Subjects: subject: Public Economics
subject: Economia brasileira
subject: Finanças públicas
subject: Vulnerabilidade externa

description: Neste trabalho, faz-se um balanço geral macroeconômico do governo Fernando Henrique Cardoso, a partir de uma análise descritiva do comportamento das principais variáveis - objetivo das políticas econômicas, indicadores de finanças públicas e de vulnerabilidade externa. Conclui-se que os prejuízos para o país, decorrentes da política econômica exclusivista de FHC, foram extremamente elevados, em face dos resultados alcançados em termos de estabilização monetária, e que o seu grande legado ao sucessor foi uma crise econômica difícil de administrar.
Acordos regionais de livre comércio e o mercado de arroz no Brasil
Creators: name: Alvim, Augusto Mussi
name: Waquil, Paulo Dabdab
name: Alvim, Augusto Mussi
name: Waquil, Paulo Dabdab
Publisher: name: Unknown
Year: 2003
Subjects: subject: International Relations/Trade
subject: Problema de Complementaridade Mista
subject: Arroz
subject: Acordos regionais

description: Este estudo identifica os efeitos dos novos acordos regionais de livre comércio sobre os produtores de arroz, no Brasil e nas demais regiões relevantes no mercado mundial. Para analisar os efeitos dos acordos comerciais, como, por exemplo, da ALCA, do MERCOSUL-UE e do MERCOSUL-CAN, desenvolve-se um modelo de alocação espacial e temporal utilizando-se um Problema de Complementaridade Mista (PCM). Em termos gerais, os maiores ganhos para os produtores brasileiros de arroz ocorreram com o acordo MERCOSUL-UE, quando a produção brasileira foi estimulada pelo redirecionamento das exportações argentinas e uruguaias para a UE. No entanto, em virtude das dificuldades nas negociações de livre comércio junto à UE, a segunda melhor opção, MERCOSUL-CAN, apresentou-se como alternativa de ganhos intermediários, mas com maior facilidade de implementação.
Additional file 2 of Unknown HIV status and the TB/HIV collaborative control program in Ethiopia: systematic review and meta-analysis
Creators: name: Balew Arega
name: Minda, Abraham
name: Getachew Mengistu
name: Mulugeta Endale
name: Asnake Agunie
Publisher: name: figshare
Year: 2020
Subjects: subject: Medicine
subject: Biotechnology
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Cancer
subject: Science Policy

description: Additional file 2. Sensitivity analysis of the proportion of unknown HIV status among patients with tuberculosis
Programas de qualidade e indicadores de desempenho da indústria de abate e processamento de suínos na região Centro Sul do Brasil
Creators: name: Da Silva Junior, Alberto Gomes
name: Gomes, Marilia Fernandes Maciel
name: Barbosa, Telma R. Da Costa G.
name: Da Silva Junior, Aziz Galvao
name: Da Silva Junior, Alberto Gomes
name: Gomes, Marilia Fernandes Maciel
name: Barbosa, Telma R. Da Costa G.
name: Da Silva Junior, Aziz Galvao
Publisher: name: Unknown
Year: 2003
Subjects: subject: Livestock Production/Industries
subject: Gestão da qualidade total
subject: Programas de qualidade
subject: Indicadores de desempenho
subject: Testes não-paramétricos
subject: Indústria de abate e processamento de suínos

description: Os programas de qualidade têm sido vistos como ferramenta essencial para solução de problemas das indústrias no Brasil; são tidos como estratégias de competitividade industrial. A crescente demanda de carnes saudáveis, em cujo processo produtivo não haja degradação ambiental, tem criado uma barreira ao comércio do produto: a exigência de qualidade. Neste trabalho, procurou-se verificar o comportamento de indicadores de desempenho das empresas de abate e processamento de suínos na região centro-sul do Brasil e sua relação com a utilização de programas de qualidade. A metodologia utilizada baseou-se na teoria da Organização Industrial e nas teorias de Competitividade e Qualidade Total, bem como em suas implicações diretas e indiretas no desempenho econômico-financeiro das organizações. Os dados utilizados foram obtidos por meio de um questionário aplicado à indústria de abate e processamento de carne suína. Os resultados desta pesquisa indicam que a referida indústria tem grande preocupação com a qualidade dos seus produtos e adota programas de qualidade em seu processo produtivo. Os programas mostraram desempenho favorável, visto que os os indicadores exibiram aumento ou melhoria, à medida que os programas de qualidade avançavam em desenvolvimento. Ao avaliar o comportamento desses indicadores de desempenho entre as empresas que adotavam algum programa formal de qualidade e as que não o faziam, comprovou-se que as primeiras tendem a apresentar melhores índices de desempenho do que as últimas. Constatou-se que os programas de qualidade implementados na indústria de abate e processamento de suínos, na região centro-sul do Brasil, estavam condizentes com as teorias de qualidade e apresentaram desempenho satisfatório. Tais programas, devido ao seu valor, possivelmente devam figurar entre as principais ferramentas estratégicas utilizadas pelas empresas de abate e processamento de suínos no Brasil para se manterem competitivas no mercado.
Hadronic vacuum polarization contribution to the muon g-2 on Euclidean windows from tau data
Creators: name: Masjuan, Pere
name: Miranda, Alejandro
name: Roig, Pablo
Publisher: name: arXiv
Year: 2024
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We computed for the first time the $τ$ data-driven Euclidean windows for the hadronic vacuum polarization contribution to the muon g-2. We showed that $τ$-based results agree with the available lattice window evaluations and with the full result. On the intermediate window, where all lattice evaluations are rather precise and agree, $τ$-based results are compatible with them. This is particularly interesting, given that the disagreement of the $e^+e^-$ data-driven result with the lattice values in this window is the main cause for their discrepancy, affecting the interpretation of the $a_μ$ measurement in terms of possible new physics.
description: 6 pages, 3 figures. Contribution to the proceedings of QNP2024 - The 10th International Conference on Quarks and Nuclear Physics, to be published in PoS
When do solar erupting hot magnetic flux ropes form?
Creators: name: Nindos, A.
name: Patsourakos, S.
name: Vourlidas, A.
name: Cheng, X.
name: Zhang, J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We investigate the formation times of eruptive magnetic flux ropes relative to the onset of solar eruptions, which is important for constraining models of coronal mass ejection (CME) initiation. We inspected uninterrupted sequences of 131 Å images that spanned more than eight hours and were obtained by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO) to identify the formation times of hot flux ropes that erupted in CMEs from locations close to the limb. The appearance of the flux ropes as well as their evolution toward eruptions were determined using morphological criteria. Two-thirds (20/30) of the flux ropes were formed well before the onset of the eruption (from 51 minutes to more than eight hours), and their formation was associated with the occurrence of a confined flare. We also found four events with preexisting hot flux ropes whose formations occurred a matter of minutes (from three to 39) prior to the eruptions without any association with distinct confined flare activity. Six flux ropes were formed once the eruptions were underway. However, in three of them, prominence material could be seen in 131 Å images, which may indicate the presence of preexisting flux ropes that were not hot. The formation patterns of the last three groups of hot flux ropes did not show significant differences. For the whole population of events, the mean and median values of the time difference between the onset of the eruptive flare and the appearance of the hot flux rope were 151 and 98 minutes, respectively. Our results provide, on average, indirect support for CME models that involve preexisting flux ropes; on the other hand, for a third of the events, models in which the ejected flux rope is formed during the eruption appear more appropriate.
description: A&A, in press
Non-supersymmetric black rings as thermally excited supertubes
Creators: name: Elvang, Henriette
name: Emparan, Roberto
name: Figueras, Pau
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct a seven-parameter family of supergravity solutions that describe non-supersymmetric black rings and black tubes with three charges, three dipoles and two angular momenta. The black rings have regular horizons and non-zero temperature. They are naturally interpreted as the supergravity descriptions of thermally excited configurations of supertubes, specifically of supertubes with two charges and one dipole, and of supertubes with three charges and two dipoles. In order to fully describe thermal excitations near supersymmetry of the black supertubes with three charges and three dipoles a more general family of black ring solutions is required.
description: 35 pages. v2: ref added and minor typo corrected
Enzymatic properties of hepatitis C virus NS3 serine protease and bio-engineering of serine protease inhibitors (serpins) against the NS3 protease and elastase
Creators: name: Po, Addy
Publisher: name: University of British Columbia
Year: 2009

description: Hepatitis C virus (HCV) has infected millions of people worldwide and emerged as a global health crisis. HCV NS3 serine protease domain (aa:1027-1218) of the HCV polyprotein, is required for the processing and maturation of the HCV viral non-structural (NS) proteins. As an essential protease for viral replication, HCV NS3 protease has been considered as a strategic target for anti-HCV drug development. This thesis investigates the designs and inhibitory properties of novel serine protease inhibitor (serpin) variants against the HCV NS3 protease. First, the substrate specificity of NS3 protease is evaluated for the purpose of generating protein-based inhibitors to target it. Data from kinetic experiments suggested that NS3 protease activity is greatly enhanced with the addition of its NS4A cofactor and that the three key residues in the substrate necessary for efficient recognition and cleavage by NS3 protease are cysteine in P1, serine/alanine in P'1 and aspartic/glutamic acids in P6 position. This information was used to bio-engineer 5 (serpins) variants based on α₁-Antitrypsin (α₁-AT) scaffold. Variants of α₁-AT contained different mutations in the serpin Reactive Site Loop (RSL) involving the P1, P4, P6 & P'1 positions. The biological activities and the newly gained specificities of the ai-AT and its variants were tested mainly by performing SDS-stable complex formation studies and enzyme kinetic experiments directed against NS3 protease and elastase. Results show that NS3 protease was able to form a 72 kDa SDS-stable complex with α₁-AT and 4 of its variants. Taken together, the ability of α₁-AT and its variants to interact and form SDS-stable complexes with NS3 protease may represent an entry point for a novel class of protein-based HCV NS3 protease inhibitors.
Fundamental differences in the radio properties of red and blue quasars: enhanced compact AGN emission in red quasars
Creators: name: Fawcett, V. A.
name: Alexander, D. M.
name: Rosario, D. J.
name: Klindt, L.
name: Fotopoulou, S.
name: Lusso, E.
name: Morabito, L. K.
name: Rivera, G. Calistro
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We have recently used the Faint Images of the Radio Sky at Twenty-centimeters (FIRST) survey to show that red quasars have fundamentally different radio properties to typical blue quasars: a significant (factor $\sim3$) enhancement in the radio-detection fraction, which arises from systems around the radio-quiet threshold with compact ($<5''$) radio morphologies. To gain greater insight into these physical differences, here we use the DR14 Sloan Digital Sky Survey (SDSS) and more sensitive, higher resolution radio data from the Very Large Array (VLA) Stripe 82 (S82) and VLA-COSMOS 3 GHz (C3GHz) surveys. With the S82 data, we perform morphological analyses at a resolution and depth three times that of the FIRST radio survey, and confirm an enhancement in radio-faint and compact red quasars over typical quasars; we now also find tentative evidence for an enhancement in red quasars with slightly extended radio structures ($16-43$ kpc at $z=1.5$). These analyses are complemented by C3GHz, which is deep enough to detect radio emission from star-formation processes. From our data we find that the radio enhancement from red quasars is due to AGN activity on compact scales ($< 43$ kpc) for radio-intermediate-radio-quiet sources ($-5
description: 17 pages, 17 Figures. Accepted for publication in MNRAS
Mixed-permutation channel with its application to estimate quantum coherence
Creators: name: Zhang, Lin
name: Zhao, Ming-Jing
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quantum channel, as the information transmitter, is an indispensable tool in quantum information theory. In this paper, we study a class of special quantum channels named the mixed-permutation channels. The properties of these channels are characterized. The mixedpermutation channels can be applied to give a lower bound of quantum coherence with respect to any coherence measure. In particular, the analytical lower bounds for l1-norm coherence and the relative entropy of coherence are shown respectively. The extension to bipartite systems is presented for the actions of the mixed-permutation channels.
description: 19 pages
Dois critérios para avaliação da eficiência técnica
Creators: name: Souza, Daniel Pacifico Homem De
name: Alves, Eliseu Roberto De Andrade
name: Souza, Daniel Pacifico Homem De
name: Alves, Eliseu Roberto De Andrade
Publisher: name: Unknown
Year: 2003
Subjects: subject: Production Economics
subject: Eficiência técnica
subject: DEA
subject: Fronteira estocástica
subject: Método Varian
subject: Critérios de avaliação.

description: Dois critérios foram utilizados para testar três métodos que estimam a eficiência técnica: o método Varian, a fronteira estocástica e a fronteira não-paramétrica, na literatura inglesa conhecida por “data envelopment analysis-DEA” e, em português, por encapsulamento de dados. A orientação pode ser para produto ou insumo, com vistas em mudar a combinação usada pelo produtor para outra, de acordo com algum critério de escolha. O trabalho se fixou em ambas as orientações. Dados de uma amostra de produtores de leite foram usados para avaliação dos métodos. O menor distúrbio na proposta de combinação de produtos ou insumos, em relação àquela usada pelos produtores, e o maior acréscimo da renda líquida constituem os critérios. Quando houver conflitos entre eles, encontrar-se-á na área de indecisão. Convém lembrar que, quanto menos diferente a combinação proposta for da original, maiores chances terá ela, como recomendação, de ser aceita pelo produtor. O método de Varian teve melhor desempenho que o DEA, em relação aos distúrbios, visto que aquele produziu, em relação a este método, menor acréscimo na renda líquida. Os distúrbios do método Varian foram maiores que os da fronteira estocástica, mas, em compensação, o incremento na renda líquida foi bem maior. Quando o ajustamento da fronteira estocástica for muito bom, certamente produzirá menores distúrbios no produto, no entanto, o mesmo pode não ocorrer em relação aos insumos, como é o caso deste trabalho. Os dados não rejeitaram a hipótese de c-racionalização; portanto, quanto aos custos, os produtores fizeram escolhas corretas, no sentido de que o agricultor A, que produziu mais que o agricultor B, não gastou menos que este. Os testes recémdesenvolvidos para o DEA, orientação produto, foram aplicados. Foi possível testar a hipótese de retorno constante versus variável. Os dados não rejeitaram a hipótese de retorno constante. A especificação meio normal para o termo do erro também não foi rejeitada, e intervalos de confiança foram estimados para os agricultores de eficiência técnica igual a 1 e para a média.
X-ray Line Emitting Objects in XMM-Newton Observations: the Tip of the Iceberg
Creators: name: Maccacaro, T.
name: Braito, V.
name: Della Ceca, R.
name: Severgnini, P.
name: Caccianiga, A.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present preliminary results from a novel search for X-ray Line Emitting Objects (XLEOs) in XMM-Newton images. Three sources have been detected in a test-run analysis of 13 XMM-Newton observations. The three objects found are most likely extremely absorbed AGN characterized by a column density NH~10^24cm^-2. Their redshift has been directly determined from the X-ray data, by interpreting the detected emission line as the 6.4 keV Fe line. The measured equivalent width of the X-ray line is, in all three cases, several keV. This pilot study demonstrates the success of our search method and implies that a large sample of XLEOs can be obtained from the public XMM-Newton data archive.
description: 10 pages, 3 figures, accepted for publication in ApJ Letters
Aplicação de sistema de apoio à decisão no planejamento de pequenas propriedades produtoras de leite da microrregião de Viçosa - MG
Creators: name: Lana, Clarisse Maia
name: Da Silva Junior, Aziz Galvao
name: Vieira, Wilson Da Cruz
name: Lana, Clarisse Maia
name: Da Silva Junior, Aziz Galvao
name: Vieira, Wilson Da Cruz
Publisher: name: Unknown
Year: 2003
Subjects: subject: Farm Management
subject: Produção de leite
subject: Sistema de apoio à decisão
subject: Alocação de recursos
subject: Programação linear.

description: A pecuária de leite nacional, nos últimos anos, vem passando por importantes transformações, impulsionadas pela necessidade de adaptação dos sistemas de produção de leite a um ambiente de maior competição. Diante desse cenário, este estudo buscou desenvolver um sistema de apoio à decisão (SAD) para auxiliar na alocação de recursos de pequenas propriedades produtoras de leite da microrregião de Viçosa - MG, visando à melhoria da rentabilidade na atividade leiteira. O sistema desenvolvido permite alocar os recursos (terra, mão-de-obra e animais) disponíveis, para a maximização da margem bruta anual por meio de um modelo de programação linear, e facilita a análise econômica dos sistemas de produção, mediante uma planilha de custo que é gerada pelos resultados do modelo. O SAD foi testado com dados de uma propriedade típica da região e mostrou-se útil na comparação de estratégias diferenciadas, no planejamento ótimo da atividade leiteira, conforme as condições de cada propriedade, e na análise da eficiência econômica dos sistemas de produção.
Weighted L^2-cohomology of Coxeter groups based on barycentric subdivisons
Creators: name: Okun, Boris L
Publisher: name: arXiv
Year: 2004
Subjects: subject: Group Theory (math.GR)
subject: Geometric Topology (math.GT)
subject: FOS: Mathematics
subject: 58G12, 20F55, 57S30, 20F32, 20J05

description: Associated to any finite flag complex L there is a right-angled Coxeter group W_L and a contractible cubical complex Sigma_L (the Davis complex) on which W_L acts properly and cocompactly, and such that the link of each vertex is L. It follows that if L is a generalized homology sphere, then Sigma_L is a contractible homology manifold. We prove a generalized version of the Singer Conjecture (on the vanishing of the reduced weighted L^2_q-cohomology above the middle dimension) for the right-angled Coxeter groups based on barycentric subdivisions in even dimensions. We also prove this conjecture for the groups based on the barycentric subdivision of the boundary complex of a simplex.
description: Published by Geometry and Topology at http://www.maths.warwick.ac.uk/gt/GTVol8/paper28.abs.html
Near horizon local instability and quantum thermality
Creators: name: Dalui, Surojit
name: Majhi, Bibhas Ranjan
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: Chaotic Dynamics (nlin.CD)
subject: Classical Physics (physics.class-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We revisit our previous proposed conjecture -- horizon creates a local instability which acts as the source of quantum temperature of black hole. It is found that a chargesless massless particle moving along the null trajectory in Eddington-Finkelstein (EF) coordinates feels instability in the vicinity of the horizon. Such instability is observer independent for this particle motion. Moreover, an observer associated to EF coordinates finds the local Hamiltonian as $xp$ where $p$ is the canonical momentum corresponding the coordinate $x$. Finally, using this Hamiltonian we notice that at the quantum level this class of observers feel the horizon as thermal object with temperature is given by the Hawking expression. We provide this by using various techniques in quantum mechanics and thereby bolstered our earlier claim -- the automatic local instability can be a mechanism for emerging horizon as a thermal object. In this process, the present analysis provides another set of coordinates (namely EF frame), in addition to our earlier Painleve ones, in which the null trajectory of the massless particle is governed by $xp$ type Hamiltonian in near the horizon regime.
description: Comments added, to appear in Phys. Rev. D
The Recruitment Niche Predicts Plant Community Assembly Across a Hydrological Gradient Along Plowed and Undisturbed Transects in a Former Agricultural Wetland
Creators: name: Valdez, Jose W.
name: Hartig, Florian
name: Fennel, Sabine
name: Poschlod, Peter
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: 580 Pflanzen (Botanik)

description: Seedling emergence in plant communities depends on the composition in the soil seed bank, in combination with species-specific responses to the environment. It is generally assumed that this juvenile transition, known as the recruitment niche, is a crucial filter that determines species’ distributions and plant community assemblies. The relative importance of this filter, however, has been widely debated. Empirical descriptions of the recruitment niche are scarce, as most field studies focus on environmental effects at later life stages. In this study, we examine the importance of the recruitment niche for predicting plant communities across a hydrological gradient in a disturbed and undisturbed area in Lake Schmiechen, Baden-Württemberg, Germany. We combine a seed bank experiment, measuring germination in water basins under standardized conditions and different water levels, with field observations of plant communities along a hydrological gradient in plowed and undisturbed transects in a former agricultural wetland. We find that hydrology consistently predicted plant community composition in both the germination experiment and in the field. The hydrological recruitment niches measured in the seed bank experiment correlated with the hydrological niche in both the plowed and undisturbed area, with slightly stronger correlation in the plowed area. We explain the latter by the fact that the seed bank experiment most closely resembles the plowed area, whereas succession and competitive interactions become more important in the undisturbed area. Our results support the view that the recruitment niche is an important driver of species composition, in both the plowed and undisturbed area. Recognizing the recruitment niche and the response of seeds within a seed bank to environmental gradients and anthropogenic disturbance is necessary to understand and predict future plant community composition.
Quarks vs. gluons in exclusive rho electroproduction
Creators: name: Diehl, M.
name: Vinnikov, A. V.
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We compare the contributions from quark and from gluon exchange to the exclusive process gamma* p -> rho0 p. We present evidence that the gluon contribution is substantial for values of the Bjorken variable xB around 0.1.
description: 7 pages, 3 figures. v2: clarification in section 3
Explainable LLM-driven Multi-dimensional Distillation for E-Commerce Relevance Learning
Creators: name: Zhao, Gang
name: Zhang, Ximing
name: Lu, Chenji
name: Zhao, Hui
name: Wu, Tianshu
name: Wang, Pengjie
name: Xu, Jian
name: Zheng, Bo
Publisher: name: arXiv
Year: 2024
Subjects: subject: Information Retrieval (cs.IR)
subject: Artificial Intelligence (cs.AI)
subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences

description: Effective query-item relevance modeling is pivotal for enhancing user experience and safeguarding user satisfaction in e-commerce search systems. Recently, benefiting from the vast inherent knowledge, Large Language Model (LLM) approach demonstrates strong performance and long-tail generalization ability compared with previous neural-based specialized relevance learning methods. Though promising, current LLM-based methods encounter the following inadequacies in practice: First, the massive parameters and computational demands make it difficult to be deployed online. Second, distilling LLM models to online models is a feasible direction, but the LLM relevance modeling is a black box, and its rich intrinsic knowledge is difficult to extract and apply online. To improve the interpretability of LLM and boost the performance of online relevance models via LLM, we propose an Explainable LLM-driven Multi-dimensional Distillation framework for e-commerce relevance learning, which comprises two core components: (1) An Explainable LLM for relevance modeling (ELLM-rele), which decomposes the relevance learning into intermediate steps and models relevance learning as a Chain-of-Thought (CoT) reasoning, thereby enhancing both interpretability and performance of LLM. (2) A Multi-dimensional Knowledge Distillation (MKD) architecture that transfers the knowledge of ELLM-rele to current deployable interaction-based and representation-based student models from both the relevance score distribution and CoT reasoning aspects. Through distilling the probabilistic and CoT reasoning knowledge, MKD improves both the semantic interaction and long-tail generalization abilities of student models. Extensive offline evaluations and online experiments on Taobao search ad scene demonstrate that our proposed framework significantly enhances e-commerce relevance learning performance and user experience.
description: Accepted by WWW 2025 oral
Medidas de produtividade: dilemas da agricultura familiar
Creators: name: Alves, Eliseu Roberto De Andrade
name: Alves, Eliseu Roberto De Andrade
Publisher: name: Unknown
Year: 2003
Subjects: subject: Production Economics
subject: Agricultura familiar
subject: Agricultura comercial
subject: Medidas de produtividade

description: O objetivo deste trabalho é isolar, em pequeno número, as premissas que têm permeado as discussões sobre agricultura familiar. Depois, por métodos elementares, elas são dedutivamente exploradas. Mostra-se que a produtividade da terra é, incorretamente, interpretada e que se deixa de lado a produtividade do trabalho, que, no contexto desse tipo de agricultura, é uma medida de bem-estar. Argumenta-se que, quando a agricultura familiar adota os métodos de decisão da agricultura capitalista, as duas medidas de produtividade devem ser substituídas pela produtividade total. A agricultura familiar escolhe uma cesta de produtos com base em seu próprio interesse e não no bem-estar dos citadinos, razão por que é pouco relevante o argumento de que produz os alimentos da cesta de consumo dos citadinos mais pobres. Deve-se interpretar esse tipo de evidência negativamente, visto que significa a existência de restrições ao bem-estar da família. Finalmente, considera-se um conjunto de dilemas, a maioria deles relacionados com as dificuldades de manter as premissas, num contexto de uma agricultura capitalista dinâmica.
Low-Contrast BIC Metasurfaces with Quality Factors Exceeding 100,000
Creators: name: Watanabe, Keisuke
name: Nagao, Tadaaki
name: Iwanaga, Masanobu
Publisher: name: arXiv
Year: 2024
Subjects: subject: Optics (physics.optics)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Dielectric metasurfaces operating at quasi-bound states in the continuum (qBICs) can achieve exceptionally high radiative quality ($\textit{Q}$) factors by introducing small asymmetries into their unit cells. However, fabrication imperfections often impose major limitations on the experimentally observed $\textit{Q}$ factors. In this study, we experimentally demonstrate BIC metasurfaces with a record-high $\textit{Q}$ factor of 101,486 under normal excitation of light in the telecom wavelength range achieved by employing low-contrast silicon pairs. Our findings show that such ultrahigh-$\textit{Q}$ factors can be attained by leveraging both the high radiative $\textit{Q}$ factors of higher-order qBIC modes and reduced scattering losses in shallow-etched designs. Additionally, we demonstrate stable sub-picometer-level wavelength fluctuations in water, with a limit of detection of $10^{-5}$ for environmental refractive index changes. The proposed approach can be extended to BIC metasurfaces with many other configurations and operating wavelengths for ultrahigh-$\textit{Q}$ applications in both fundamental physics and advanced devices.
description: 20 pages, 4 main figures + 4 supporting figures
Additional file 1 of Estimates of female genital mutilation/cutting in the Netherlands: a comparison between a nationwide survey in midwifery practices and extrapolation-model
Creators: name: Kawous, Ramin
name: Muijsenbergh, Maria E. T. C. Van Den
name: Geraci, Diana
name: Hendriks, Kyra R. M.
name: Ortensi, Livia E.
name: Hilverda, Femke
name: Burdorf, Alex
Publisher: name: figshare
Year: 2020
Subjects: subject: Medicine
subject: Biotechnology
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Cancer
subject: Science Policy

description: Additional file 1. Demographic Health Survey (DHS) and Multiple Indicator Cluster Survey (MICS) data: country of origin, source and year of publication, overall prevalence and the prevalence of Type III; and Statistics Netherlands dataset on first-generation women giving birth; and estimated numbers of cut women giving birth by Type III.
Cosmological implications of the KOTO excess
Creators: name: Altmannshofer, Wolfgang
name: Lehmann, Benjamin V.
name: Profumo, Stefano
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The KOTO experiment has reported an excess of $K_L\toπ^0ν\barν$ events above the Standard Model prediction, in tension with the Grossman-Nir (GN) bound. The GN bound heavily constrains new physics interpretations of an excess in this channel, but another possibility is that the observed events originate from a different process entirely: a decay of the form $K_L\toπ^0X$, where $X$ denotes one or more new invisible species. We introduce a class of models to study this scenario with two light scalars playing the role of $X$, and we examine the possibility that the lighter of the two new states may also account for cosmological dark matter (DM). We show that this species can be produced thermally in the presence of additional interactions apart from those needed to account for the KOTO excess. Conversely, in the minimal version of the model, DM must be produced nonthermally. In this case, avoiding overproduction imposes constraints on the structure of the low-energy theory. Moreover, this requirement carries significant implications for the scale of reheating in the early Universe, generically preferring a low but observationally permitted reheating temperature of O(10 MeV). We discuss astrophysical and terrestrial signatures that will allow further tests of this paradigm in the coming years.
description: 43 pages, 10 figures. Matched published version
Additional file 1 of Unknown HIV status and the TB/HIV collaborative control program in Ethiopia: systematic review and meta-analysis
Creators: name: Balew Arega
name: Minda, Abraham
name: Getachew Mengistu
name: Mulugeta Endale
name: Asnake Agunie
Publisher: name: figshare
Year: 2020
Subjects: subject: Medicine
subject: Biotechnology
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Cancer
subject: Science Policy

description: Additional file 1. Quality of studies included in the meta analysis tassese the proportion of unknown HIV status among patients with tuberculosis
Alternativas de políticas comerciais para o agronegócio brasileiro sob diferentes pressuposições de retorno à escala
Creators: name: Gurgel, Angelo Costa
name: Campos, Antonio Carvalho
name: Gurgel, Angelo Costa
name: Campos, Antonio Carvalho
Publisher: name: Unknown
Year: 2003
Subjects: subject: International Relations/Trade
subject: Política comercial
subject: Economias de escala
subject: Equilíbrio geral

description: Este trabalho procura determinar os impactos de diferentes opções de política comercial, sob pressuposições alternativas de retornos à escala e natureza da competição, nos segmentos industriais, com ênfase especial nas indústrias ligadas ao agronegócio. O modelo de equilíbrio geral aplicado, GTAPinGAMS, é usado para implementar as simulações. Os resultados sugerem que os ganhos de bem-estar tenham sido superiores no modelo que considera as imperfeições de mercado. As variações setoriais na produção, importações e exportações foram levemente diferentes em magnitudes e sinais, sob pressuposições alternativas de estruturas de mercados, e dependentes da política comercial implementada. As diferentes medidas de política comercial permitem o aproveitamento de economias de escala e a redução do markup na maioria das indústrias, com evidências nos efeitos de racionalização e procompetitivos.
Stochastic modelling of the instantaneous velocity profile in rough-wall turbulent boundary layers
Creators: name: Ehsani, Roozbeh
name: Heisel, Michael
name: Li, Jiaqi
name: Voller, Vaughan
name: Hong, Jiarong
name: Guala, Michele
Publisher: name: arXiv
Year: 2024
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: The statistical properties of Uniform Momentum Zones (UMZs) are extracted from laboratory and field measurements in rough wall turbulent boundary layers to formulate a set of stochastic models for the simulation of instantaneous velocity profiles. A spatio-temporally resolved velocity dataset, covering a field of view of $8 \times 9$ m$^2$, was obtained in the atmospheric surface layer using super-large-scale particle image velocimetry (SLPIV), as part of the Grand-scale Atmospheric Imaging Apparatus (GAIA). Wind tunnel data from a previous study are included for comparison \citep{heisel2020mixing}. The probability density function of UMZ attributes such as their thickness, modal velocity, and averaged vertical velocity are built at varying elevations and modeled using log-normal and Gaussian distributions. Inverse transform sampling of the distributions is used to generate synthetic step-like velocity profiles that are spatially and temporally uncorrelated. Results show that in the wide range of wall-normal distances and $Re_τ$ up to $ \sim O(10^6)$ investigated here, shear velocity scaling is manifested in the velocity jump across shear interfaces between adjacent UMZs, and attached eddy behavior is observed in the linear proportionality between UMZ thickness and their wall normal location. These very same characteristics are recovered in the generated instantaneous profiles, using both a fully stochastic and a data-driven hybrid stochastic models, which address, in different ways, the coupling between modal velocities and UMZ thickness. Our method provides a stochastic approach for generating an ensemble of instantaneous velocity profiles, consistent with the structural organization of UMZs, where the ensemble reproduces the logarithmic mean velocity profile and recovers significant portions of the Reynolds stresses and thus of the streamwise and vertical velocity variability.
Additional file 1 of NASQAR: a web-based platform for high-throughput sequencing data analysis and visualization
Creators: name: Yousif, Ayman
name: Drou, Nizar
name: Rowe, Jillian
name: Khalfan, Mohammed
name: Gunsalus, Kristin C.
Publisher: name: figshare
Year: 2020
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Artificial Intelligence and Image Processing
subject: FOS: Computer and information sciences
subject: Computation Theory and Mathematics
subject: Information Systems

description: Additional file 1 This file includes supplementary materials such as instructions on how to launch NASQAR and example use cases on data analysis and visualization.
Simulation-Aided Policy Tuning for Black-Box Robot Learning
Creators: name: He, Shiming
name: von Rohr, Alexander
name: Baumann, Dominik
name: Xiang, Ji
name: Trimpe, Sebastian
Publisher: name: arXiv
Year: 2024
Subjects: subject: Robotics (cs.RO)
subject: Machine Learning (cs.LG)
subject: Systems and Control (eess.SY)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: How can robots learn and adapt to new tasks and situations with little data? Systematic exploration and simulation are crucial tools for efficient robot learning. We present a novel black-box policy search algorithm focused on data-efficient policy improvements. The algorithm learns directly on the robot and treats simulation as an additional information source to speed up the learning process. At the core of the algorithm, a probabilistic model learns the dependence of the policy parameters and the robot learning objective not only by performing experiments on the robot, but also by leveraging data from a simulator. This substantially reduces interaction time with the robot. Using this model, we can guarantee improvements with high probability for each policy update, thereby facilitating fast, goal-oriented learning. We evaluate our algorithm on simulated fine-tuning tasks and demonstrate the data-efficiency of the proposed dual-information source optimization algorithm. In a real robot learning experiment, we show fast and successful task learning on a robot manipulator with the aid of an imperfect simulator.
Search for the Skyrme-Hartree-Fock Solutions for Chiral Rotation in N=75 Isotones
Creators: name: Olbratowski, P.
name: Dobaczewski, J.
name: Dudek, J.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A search for the self-consistent solutions for the chiral rotational bands in the N=75 isotones, 130Cs, 132La, 134Pr and 136Pm is performed within the Skyrme-Hartree-Fock cranking approach using SKM* and SLy4 parametrizations. The dependence of the solutions on the time-odd contributions in the energy functional is studied. From among the considered four isotones, self-consistent chiral solutions are obtained only in 132La. The microscopic calculations are compared with the 132La experimental data and with results of a classical model that contains all the mechanisms underlying the chirality of the collective rotational motion. Strong similarities between the HF and classical model results are found. The suggestion formulated earlier by the authors that the chiral rotation cannot exist below a certain critical frequency is further illustrated and discussed, together with the microscopic origin of a transition from the planar to chiral rotation in nuclei. We also formulate the separability rule by which the Tilted-Axis-Cranking solutions can be inferred from three independent Principal-Axis-Cranking solutions corresponding to three different axes of rotation.
description: 23 LaTeX pages, 11 PostScript Figures
Federal Tax Policies and Farm Households
Creators: name: Durst, Ron L.
name: Durst, Ron L.
Publisher: name: Unknown
Year: 2009
Subjects: subject: Farm Management
subject: income tax
subject: estate tax
subject: tax rates
subject: estate
subject: Federal tax policy
subject: farm losses
subject: commercial farms

description: Significant changes in Federal individual income and estate tax policies have occurred over the last 10 years. Analysis suggests that changes in Federal tax provisions affecting both individual and business income taxes have reduced average tax rates for all farm households, resulting in the lowest tax burden on farm income and investment in a decade. Similarly, an analysis of the changes to Federal estate tax policies suggests that increases in the value of property that can be transferred to the next generation free of the estate tax, combined with special provisions for farmers and other small businesses, have greatly reduced the number of farm estates subject to the tax and the amount owed. While nearly 10 percent of commercial farm estates could owe tax in 2009, only 1 to 2 percent of all farm estates are estimated to be subject to the Federal estate tax this year.