Resummation and Shower Studies

The transverse momentum spectra of the Z and Higgs bosons are studied, as probes of the consequences of multiple parton emissions in hadronic events. Emphasis is put on constraints, present in showers, that go beyond conventional leading log. It is shown that, if such constraints are relaxed, better agreement can be obtained with experimental data and with resummation descriptions.Comment: 6 pages, LaTeX, 3 eps figures, submitted to the proceedings of the Workshop on Physics at TeV Colliders, Les Houches, France, 26 May -- 6 June 200

The meaning of having to live with cancer in old age.

Little is known about how older people with cancer experience their life situation. To increase the understanding of how illness is experienced in older people with cancer, the aim of this study was to investigate the meaning of living with cancer in old age. The hermeneutic phenomenological method as described by van Manen and referred to as 'phenomenology of praxis' was used. Ten persons (seven women and three men) aged 75 and over, who had a diagnosis of cancer and who had just completed cancer treatment, were interviewed in their own homes. The analysis revealed a life world affected to varying degrees by the cancer disease. The lived experiences across the interviews were revealed in four overarching essential themes: transition into a more or less disintegrated existence, sudden awareness of the finiteness of life, redefinition of one's role in life for good and for bad, meeting disease and illness. To provide individual support and appropriate care to older people with cancer it is important for health care professionals to identify and take care of disabilities and to support the reorientation in the disintegrated life situation. It is also important to have preparedness to meet the old person's thoughts about death. Thus, it is important to encourage the old person to describe her/his illness experience to increase understanding about what is meaningful for her/him

Agregación de valor a los hongos comestibles silvestres a través de procesos de deshidratado

Objective: To propose processes of dehydration of wild edible mushrooms as a strategy of adding value to the traditional harvesting of mycological resources, in forest areas of the State of Mexico. Design, methodology and approximation: Simple case study method with a mixed approach, which integrates the perspective of a business plan. Results: There are favorable conditions to add value to the collection of wild edible mushrooms, through dehydration processes. It is a low-cost initiative, based on local mycological diversity and ethnomicological knowledge, but requires the formation of new capacities to guarantee its technical and financial viability. Limitations and implications: The study is exploratory in nature, so its relevance only helps to guide the processes of value aggregation in forest territories. Findings and conclusions: The lack of innovation in mushrooms harvesting generates conditions of marginality among mushrooms pickers. Innovations such as dehydration can help control the unpredictability of the product, its conservation and its entry into new markets. This requires investment in equipment, human capital and greater knowledge of the market.Objetivo: Proponer procesos de deshidratado de hongos comestibles silvestres como estrategia de agregación de valor a la recolección tradicional de los recursos micológicos, en espacios forestales del Estado de México. Diseño, metodología y aproximación: Método de estudio de caso simple con un enfoque mixto, que integra la perspectiva de un plan de negocios. Resultados: Existen condiciones favorables para la agregación de valor a las actividades de recolección e intercambio tradicionales de hongos comestibles silvestres, mediante procesos de deshidratación. Es una iniciativa de bajo coste, basada en la micodiversidad local y los conocimientos etnomicológicos, pero requiere la formación de nuevas capacidades para garantizar su viabilidad técnica y financiera.   Limitaciones e implicaciones: El estudio es de carácter exploratorio por lo que su relevancia sólo contribuye a orientar los procesos de agregación de valor en territorios forestales. Hallazgos y conclusiones: La falta de innovación en la recolección e intercambio de hongos genera condiciones de marginalidad entre los recolectores. Innovaciones como la deshidratación pueden contribuir a controlar la impredecibilidad del producto, su conservación y su ingreso a nuevos mercados. Para ello se requiere inversión en equipamiento, capital humano y un mayor conocimiento del mercado

Comparative study of radiation-induced damage in magnesium aluminate spinel by means of IL, CL and RBS/C techniques

International audienceA comparative study of damage accumulation in magnesium aluminate spinel (MgAl2O4) has been conducted using ionoluminescence (IL), cathodoluminescence (CL) and Rutherford Backscattering Spectrometry/channeling (RBS/C) techniques. MgAl2O4 single crystal and polycrystalline samples were irradiated with 320 keV Ar+ ions at fluencies ranging from 1 × 1012 to 2 × 1016 cm−2 in order to create various levels of radiation damage. RBS/C measurements provided quantitative data about damage concentration in the samples. These values were then compared to the luminescence measurements. The results obtained by IL and RBS/C methods demonstrate a two-step character of damage buildup process. The CL data analysis points to the three-step damage accumulation mechanism involving the first defect transformation at fluencies of about 1013 cm−2 and second at about 1015 cm−2. The rate of changes resulting from the formation of nonluminescent recombination centers is clearly nonlinear and cannot be described in terms of continuous accumulation of point defects. Both, IL and CL techniques, appear as new, complementary tools bringing new possibilities in the damage accumulation studies in single- and polycrystalline materials

The Saffman-Taylor problem on a sphere

The Saffman-Taylor problem addresses the morphological instability of an interface separating two immiscible, viscous fluids when they move in a narrow gap between two flat parallel plates (Hele-Shaw cell). In this work, we extend the classic Saffman-Taylor situation, by considering the flow between two curved, closely spaced, concentric spheres (spherical Hele-Shaw cell). We derive the mode-coupling differential equation for the interface perturbation amplitudes and study both linear and nonlinear flow regimes. The effect of the spherical cell (positive) spatial curvature on the shape of the interfacial patterns is investigated. We show that stability properties of the fluid-fluid interface are sensitive to the curvature of the surface. In particular, it is found that positive spatial curvature inhibits finger tip-splitting. Hele-Shaw flow on weakly negative, curved surfaces is briefly discussed.Comment: 26 pages, 4 figures, RevTex, accepted for publication in Phys. Rev.

Two-Center Integrals for r_{ij}^{n} Polynomial Correlated Wave Functions

All integrals needed to evaluate the correlated wave functions with polynomial terms of inter-electronic distance are included. For this form of the wave function, the integrals needed can be expressed as a product of integrals involving at most four electrons

Fluctuations in Hadronic and Nuclear Collisions

We investigate several fluctuation effects in high-energy hadronic and nuclear collisions through the analysis of different observables. To introduce fluctuations in the initial stage of collisions, we use the Interacting Gluon Model (IGM) modified by the inclusion of the impact parameter. The inelasticity and leading-particle distributions follow directly from this model. The fluctuation effects on rapidity distributions are then studied by using Landau's Hydrodynamic Model in one dimension. To investigate further the effects of the multiplicity fluctuation, we use the Longitudinal Phase-Space Model, with the multiplicity distribution calculated within the hydrodynamic model, and the initial conditions given by the IGM. Forward-backward correlation is obtained in this way.Comment: 22 pages, RevTex, 8 figures (included); Invited paper to the special issue of Foundation of Physics dedicated to Mikio Namiki's 70th. birthda

Collision geometry scaling of Au+Au pseudorapidity density from sqrt(s_NN) = 19.6 to 200 GeV

The centrality dependence of the midrapidity charged particle multiplicity in Au+Au collisions at sqrt(s_NN) = 19.6 and 200 GeV is presented. Within a simple model, the fraction of hard (scaling with number of binary collisions) to soft (scaling with number of participant pairs) interactions is consistent with a value of x = 0.13 +/- 0.01(stat) +/- 0.05(syst) at both energies. The experimental results at both energies, scaled by inelastic p(pbar)+p collision data, agree within systematic errors. The ratio of the data was found not to depend on centrality over the studied range and yields a simple linear scale factor of R_(200/19.6) = 2.03 +/- 0.02(stat) +/- 0.05(syst).Comment: 5 pages, 4 figures, submitted to PRC-R

Multiple Interactions and the Structure of Beam Remnants

Recent experimental data have established some of the basic features of multiple interactions in hadron-hadron collisions. The emphasis is therefore now shifting, to one of exploring more detailed aspects. Starting from a brief review of the current situation, a next-generation model is developed, wherein a detailed account is given of correlated flavour, colour, longitudinal and transverse momentum distributions, encompassing both the partons initiating perturbative interactions and the partons left in the beam remnants. Some of the main features are illustrated for the Tevatron and the LHC.Comment: 69pp, 33 figure

Peacock bass mortality associated with catch-and-release sport fishing in the Negro River, Amazonas State, Brazil

Sport fishing for peacock bass Cichla spp. in the Brazilian Amazon has increased in popularity and attracts anglers who generate significant economic benefits in rural regions. The sustainability of this fishery is partly dependent on the survival of fish caught through catch-and-release fishing. The objective of this work was to investigate, hooking mortality of Cichla spp., including speckled peacock bass (C. temensis Humbolt), butterfly peacock bass (C. orinocensis Humbolt), and popoca peacock bass (C. monoculus Agassiz) in the basin of the Negro River, the largest tributary of the Amazon River. Fish were caught at two different sites using artificial lures, transported to pens anchored in the river and monitored for 72 hours. A total of 162 individual peacock bass were captured and hooking mortality (mean % ± 95% confidence intervals) was calculated. Mean mortality was 3.5% (± 5.0), 2.3% (± 3.5) and 5.2% (± 10.2) for speckled peacock bass, butterfly peacock bass, and popoca peacock bass, respectively. Lengths of captured fish ranged from 26 to 79 cm (standard length), however, only fish under 42 cm died. This research suggests that catch-and-release sport fishing of peacock bass does not result in substantial mortality in the Negro River basin.A pesca esportiva de tucunarés Cichla spp., na Amazônia brasileira, aumentou em popularidade nos últimos anos e tem atraído pescadores esportivos que geram benefícios econômicos para essa região. Entretanto, a sustentabilidade dessa pescaria depende em parte da sobrevivência dos peixes capturados por meio da prática do pesque e solte. O objetivo deste trabalho foi avaliar a mortalidade de Cichla spp., incluindo o tucunaré paca (C. temensis Humbolt), o borboleta (C. orinocensis Humbolt) e o popoca (C. monoculus Agassiz) em dois locais na bacia do rio Negro, o maior tributário do rio Amazonas. Os peixes foram capturados por variados tipos de iscas artificiais e posteriormente monitorados em viveiros construídos no próprio rio por 72 horas. Um total de 162 tucunarés foi capturado, e as mortalidades (% ± intervalo de confiança 95%) foram calculadas. A mortalidade foi 3,5% (± 5,0), 2,3% (± 3,2) e 5,2% (±10,2) para o paca, o borboleta e o popoca, respectivamente. O comprimento padrão dos peixes capturados variou de 26 a 79 cm, mas apenas os peixes menores até 42 cm morreram. A pesquisa sugere que a pesca esportiva não causou substancial mortalidade na população de Cichla spp. na bacia do rio Negro