18 research outputs found
Study of and from and Decays
We use the decay modes and to
study the scalar mesons and within perturbative QCD
framework. For , we perform our calculation in two
scenarios of the scalar meson spectrum. The results indicate that scenario II
is more favored by experimental data than scenario I. The important
contribution from annihilation diagrams can enhance the branching ratios about
50% in scenario I, and about 30% in scenario II. The predicted branching ratio
of in scenario I is also less favored by the experiments.
The direct CP asymmetries in are small, which are
consistent with the present experiments.Comment: More references are added. Published Versio
Heavy quarkonium: progress, puzzles, and opportunities
A golden age for heavy quarkonium physics dawned a decade ago, initiated by
the confluence of exciting advances in quantum chromodynamics (QCD) and an
explosion of related experimental activity. The early years of this period were
chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in
2004, which presented a comprehensive review of the status of the field at that
time and provided specific recommendations for further progress. However, the
broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles
could only be partially anticipated. Since the release of the YR, the BESII
program concluded only to give birth to BESIII; the -factories and CLEO-c
flourished; quarkonium production and polarization measurements at HERA and the
Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the
deconfinement regime. All these experiments leave legacies of quality,
precision, and unsolved mysteries for quarkonium physics, and therefore beg for
continuing investigations. The plethora of newly-found quarkonium-like states
unleashed a flood of theoretical investigations into new forms of matter such
as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the
spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b},
and b\bar{c} bound states have been shown to validate some theoretical
approaches to QCD and highlight lack of quantitative success for others. The
intriguing details of quarkonium suppression in heavy-ion collisions that have
emerged from RHIC have elevated the importance of separating hot- and
cold-nuclear-matter effects in quark-gluon plasma studies. This review
systematically addresses all these matters and concludes by prioritizing
directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K.
Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D.
Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A.
Petrov, P. Robbe, A. Vair
Specification of the near-Earth space environment with SHIELDS
Predicting variations in the near-Earth space environment that can lead to spacecraft damage and failure is one example of âspace weatherâ and a big space physics challenge. A project recently funded through the Los Alamos National Laboratory (LANL) Directed Research and Development (LDRD) program aims at developing a new capability to understand, model, and predict Space Hazards Induced near Earth by Large Dynamic Storms, the SHIELDS framework. The project goals are to understand the dynamics of the surface charging environment (SCE), the hot (keV) electrons representing the source and seed populations for the radiation belts, on both macro- and micro-scale. Important physics questions related to particle injection and acceleration associated with magnetospheric storms and substorms, as well as plasma waves, are investigated. These challenging problems are addressed using a team of world-class experts in the fields of space science and computational plasma physics, and state-of-the-art models and computational facilities. A full two-way coupling of physics-based models across multiple scales, including a global MHD (BATS-R-US) embedding a particle-in-cell (iPIC3D) and an inner magnetosphere (RAM-SCB) codes, is achieved. New data assimilation techniques employing in situ satellite data are developed; these provide an order of magnitude improvement in the accuracy in the simulation of the SCE. SHIELDS also includes a post-processing tool designed to calculate the surface charging for specific spacecraft geometry using the Curvilinear Particle-In-Cell (CPIC) code that can be used for reanalysis of satellite failures or for satellite design
Bioterrorismo, riscos biológicos e as medidas de biossegurança aplicåveis ao Brasil
Death of pastures syndrome: tissue changes in Urochloa hybrida cv. Mulato II and Urochloa brizantha cv. Marandu
Anatomia e densidade bĂĄsica da madeira de Caesalpinia pyramidalis Tul. (Fabaceae), espĂ©cie endĂȘmica da caatinga do Nordeste do Brasil
O estado atual do conhecimento da diversidade dos Cladocera (Crustacea, Branchiopoda) nas ĂĄguas doces do estado de Minas Gerais
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time, and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space. While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes, vast areas of the tropics remain understudied. In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity, but it remains among the least known forests in America and is often underrepresented in biodiversity databases. To worsen this situation, human-induced modifications may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge, it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%â18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
Relação zinco cobre em dietas de codornas japonesas em postura
RESUMO Objetivou-se verificar o efeito da suplementação de diferentes relaçÔes de zinco orgĂąnico e de cobre inorgĂąnico, bem como comparar os resultados com a dieta controle de codornas japonesas, sobre o desempenho produtivo e a qualidade dos ovos. Foram realizados dois experimentos na ĂĄrea experimental da Universidade Federal do EspĂrito Santo: variando os nĂveis de zinco orgĂąnico e mantendo os de cobre recomendados e outro variando os nĂveis de cobre inorgĂąnico. O perĂodo experimental foi de 84 dias, divididos em perĂodos de 21 dias. Foram usadas cinco prĂ©-misturas minerais. Foram analisadas variĂĄveis de desempenho e qualidade dos ovos. Foi observado primeiramente que as variĂĄveis avaliadas nĂŁo foram afetadas de forma significativa pelas diferentes relaçÔes dos minerais, exceto para pesos relativo e absoluto da casca. No segundo ensaio, nĂŁo houve interação entre os nĂveis de zinco e de cobre nem entre estes e a dieta controle, para nenhuma das variĂĄveis observadas; quando analisadas as mĂ©dias individuais, foi observada diferença significativa para taxa de postura, relação ovos comerciais e totais, consumo de ração e na unidade Haugh. Pode-se concluir que a relação de 35mg/kg de zinco orgĂąnico e a de 3,5mg/kg de cobre inorgĂąnico atenderam as necessidades nutricionais dos animais para desempenho e qualidade de ovos
Zinc copper ratio of Japanese quails diets posture
<p></p><p>ABSTRACT The objective of this study was to verify the effect of the supplementation of different organic zinc and inorganic copper ratios and to compare the results with the Japanese quail control diet on the productive performance and egg quality. Two experiments were carried out in the experimental area of the Federal University of EspĂrito Santo, varying the levels of organic zinc and maintaining the recommended copper and the other varying levels of inorganic copper. The experimental period was 84 days. Five mineral premixes were used. Performance and egg quality variables were analyzed. It was first observed that the evaluated variables were not affected significantly by the different mineral relations, except for relative and absolute weight of the bark. In the second test, there was no interaction between the zinc and copper levels, neither between the control and the control diet, for any of the variables observed, when analyzing the individual means, a significant difference was observed for posture rate, commercial and total eggs ratio, feed intake, and in the Haugh Unit. It can be concluded that the ratio of 35mg/kg organic zinc and 3,5mg/kg of inorganic copper met the nutritional requirements of the animals for performance and egg quality.</p><p></p