Collective behavior in nuclear interactions and shower development

The mechanism of hadronic interactions at very high energies is still unclear. Available accelerator data constrain weakly the forward rapidity region which determines the development of atmospheric showers. This ignorance is one of the main sources of uncertainty in the determination of the energy and composition of the primary in hadron-induced atmospheric showers. In this paper we examine the effect on the shower development of two kinds of collective effects in high-energy hadronic interactions which modify the production of secondary particles. The first mechanism, modeled as string fusion, affects strongly the central rapidity region but only slightly the forward region and is shown to have very little effect on the shower development. The second mechanism implies a very strong stopping; it affects modestly the profile of shower maximum but broadens considerably the number distribution of muons at ground. For the latter mechanism, the development of air showers is faster mimicking a heavier projectile. On the other hand, the number of muons at ground is lowered, resembling a shower generated by a lighter primary.Comment: 17 pages, 10 figure

On the long-range correlations in hadron-nucleus collisions

Long-range correlations between multiplicities in different rapidity windows in hadron-nucleus collisions are analyzed. After recalling the standard results in the probabilistic model, we study them in the framework of perturbative QCD. Considering interacting BFKL pomerons in the form of fan diagrams coupled to a dilute projectile, analytic estimates are done for very large rapidities. The correlation strength results weakly depending on energy and centrality or nuclear size, and generically greater than unity. Finally, we turn to the Color Glass Condensate framework. For a saturated projectile and considering the most feasible experimental situation of forward and backward rapidity windows symmetric around the center-of-mass, the resulting correlation strength turns out to be larger than unity and shows a non-monotonic behavior with increasing energy, first increasing and then decreasing to a limiting value. Its behavior with increasing centrality or nuclear size depends on the considered rapidity windows.Comment: 17 pages, LaTeX, 6 eps figures included using graphicx; v2: error in the CGC formula corrected, conclusions of the corresponding section changed accordingl

Desenvolvimento de cenários futuros possíveis para o manejo florestal sustentável em Jaci Paraná, Porto Velho, Rondônia, Brasil.

O presente trabalho refere-se aos resultados obtidos com a utilização da metodologia Cenários Futuros Possíveis, referendada pelo Programa ASB Partnership for the Tropical Forest Margins do Centro Mundial de Sistemas Agroflorestais ICRAF, sediado no Quênia, África. O referido programa realizou na cidade de Chiang Mai, Tailândia, de 17 a 28 de novembro de 2004, um treinamento sobre esta metodologia, do qual participaram dois autores deste relatório. Os cenários futuros possíveis têm sido utilizados desde a década de 50 para diversas finalidades, tais como o planejamento estratégico de empresas multinacionais, o planejamento regional, entre outras. No caso especifico desse treinamento, o objetivo foi criar uma rede de facilitadores para promover o uso de cenários futuros com grupos de produtores urais, e,ou, comunidades, na construção coletiva de cenários possíveis de serem concretizados considerando os aspectos técnicos, sociais e políticos interligados à determinada realidade ambiental.bitstream/CPAF-RO-2010/14326/1/doc113-manejoflorestalsustentavel.pd

Forward production of beauty baryons in pp collisions at LHC

The production of charmed and beauty baryons in proton-proton collisions at high energies is analyzed within the modified quark-gluon string model. We present some predictions for the experiments on the forward beauty baryon production in pp collisions at LHC energies. This analysis allows us to find useful information on the Regge trajectories of the heavy (b barb) mesons and the sea beauty quark distributions in the proton.Comment: 14 pages, 12 figure

Universal behavior of baryons and mesons' transverse momentum distributions in the framework of percolation of strings

In the framework of percolation of strings, we present predictions for the $R_{AA}$ and $R_{CP}$ for mesons and baryons and for $\bar{p}/\pi^{0}$ ratios at LHC energies.Comment: Presented at "Heavy Ion Collisions at the LHC: last call for predictions", Geneva Switzerland, May 14th-June 8t

Simultaneous optimization of circadian and color performance for smart lighting systems design

We present in this work a method to design lighting sources that can be adapted to different temperatures of color and, simultaneously, with a tunable circadian character. We obtained an acceptable range of tuning in both parameters compared to the bibliography. This kind of lighting source has potential applications particularly in building lighting, but also in farming or agriculture. At the same time, we have shown the possibilities of multiobjective optimizations in the lighting industry. The optimization has been developed using the Genetic Algorithm and multiobjective merit functions. The lighting source is able to work under two different regimes regarding the circadian effect, with a design based on a combination of two monochromatic and two white Lighting Emitting Diodes (enough for controlling the circadian character and the color performance at the same time). A prototype, which can be manually or automatically controlled, has been also implemented and evaluated, with a performance in terms of color coordinates very close to the daylight, showing a modulation of the Circadian Efficacy of Radiation between 6% and 16%, and a Color Rendering Index above 80%

Actividad antiinflamatoria del extracto etanólico de las hojas de Manihot esculenta Crantz (yuca) en un modelo experimental de inflamación aguda: Anti-inflammatory activity of the ethnolic extract of the leaves of manihot esculenta Crantz (yuca) in an experimental model of acute inflammation

Introduction: Manihot esculenta Crantz (yucca) leaves have been used around the world and over time in order to decrease the anti-inflammatory response. Objective: To evaluate the anti-inflammatory activity of the ethanolic extract of the Manihot esculenta Crantz leaf in rats. Methods: An experimental study was conducted. The study population included 60 albino rats sp. Rattus novergicus, distributed in 4 groups of 15 rats each. A homogeneous solution of ethanolic extract of Manihot esculenta Crantz leaves was used for intraperitoneal administration. Carrageenan was used as an inflammatory inducer that was administered intradermally; for the measurement of plantar edema, the Digital Water Plethysmometer (LE7500) was used. Tween 80 / water solution (1:10) was administered to the negative control group at a dose of 1mL./100g., To the betamethasone positive control group 4mg / Kg and to treatment groups 1 and 2 Manihot esculenta Crantz, 2 mg / kg and 4 mg / kg, respectively. The 1-tail ANOVA test and the Tukey post hoc test were used for comparisons between the groups. Results: In 37.67% of treatment group 2 a reduction in edema was observed 3 hours after administering Manihot esculenta Crantz (p <0.05). In both administration groups of Manihot esculenta Crantz there was a nonsignificant trend to reduce plantar edema with values close to significance. Conclusion: The Manihot esculenta Crantz ethanolic extract at a 4 mg / kg dose probably have anti-inflammatory activity in this animal model of acute inflamation.Introducción: Las hojas de Manihot esculenta Crantz (yuca) han sido usadas alrededor del mundo y a lo largo del tiempo con el fin de disminuir la respuesta antiinflamatoria. Objetivo: Evaluar la actividad antiinflamatoria del extracto etanólico de la hoja de Manihot esculenta crantz en ratas. Métodos: Se realizó un estudio tipo experimental. La población de estudio fueron 60 ratas albinas sp. Rattus novergicus, distribuidas en 4 grupos de 15 ratas cada uno. Se usó una solución homogénea de extracto etanólico de hojas de Manihot esculenta crantz para su administración vía intraperitoneal. Se utilizó carragenina como inductor inflamatorio, que fue administrado por vía intradérmica; para la medición del edema plantar, se hizo uso del Digital Water Plethysmometer (LE7500). Se administró al grupo control negativo solución de tween 80/agua (1:10) a dosis de 1ml/10g., al grupo control positivo betametasona 4mg/Kg y a los grupos de tratamiento 1 y 2 Manihot esculenta crantz, 2 mg/kg y 4 mg/kg, respectivamente. Se utilizó la prueba de ANOVA de 1 cola y la prueba post-hoc de Tukey, para las comparaciones entre los grupos. Resultados: En el 37,67% del grupo de tratamiento 2 se observó una reducción del edema a las 3 horas de administrar Manihot esculenta crantz (p <0,05). En otras mediciones se encontró una tendencia no significativa en ambos grupos de administración de Manihot esculenta crantz a la reducción del edema plantar. Conclusión: El extracto etanólico de Manihot sculenta a partir de la dosis de 4 mg/kg parece tener actividad antiinflamatoria en la reducción del edema plantar en el modelo animal utilizado

Feynman scaling violation on baryon spectra in pp collisions at LHC and cosmic ray energies

A significant asymmetry in baryon/antibaryon yields in the central region of high energy collisions is observed when the initial state has non-zero baryon charge. This asymmetry is connected with the possibility of baryon charge diffusion in rapidity space. Such a diffusion should decrease the baryon charge in the fragmentation region and translate into the corresponding decrease of the multiplicity of leading baryons. As a result, a new mechanism for Feynman scaling violation in the fragmentation region is obtained. Another numerically more significant reason for the Feynman scaling violation comes from the fact that the average number of cutted Pomerons increases with initial energy. We present the quantitative predictions of the Quark-Gluon String Model (QGSM) for the Feynman scaling violation at LHC energies and at even higher energies that can be important for cosmic ray physics.Comment: 21 pages, 11 figures, and 1 table. arXiv admin note: substantial text overlap with arXiv:1107.1615, arXiv:1007.320

Medium-modified evolution of multiparticle production in jets in heavy-ion collisions

The energy evolution of medium-modified average multiplicities and multiplicity fluctuations in quark and gluon jets produced in heavy-ion collisions is investigated from a toy QCD-inspired model. In this model, we use modified splitting functions accounting for medium-enhanced radiation of gluons by a fast parton which propagates through the quark gluon plasma. The leading contribution of the standard production of soft hadrons is found to be enhanced by the factor $\sqrt{N_s}$ while next-to-leading order (NLO) corrections are suppressed by $1/\sqrt{N_s}$, where the nuclear parameter $N_s>1$ accounts for the induced-soft gluons in the hot medium. The role of next-to-next-to-leading order corrections (NNLO) is studied and the large amount of medium-induced soft gluons is found to drastically affect the convergence of the perturbative series. Our results for such global observables are cross-checked and compared with their limits in the vacuum and a new method for solving the second multiplicity correlator evolution equations is proposed.Comment: 21 pages and 8 figures, typo corrections, references adde

Charm Production in DPMJET

In this work, charm production in the {\sc dpmjet} hadronic jet simulation is compared to experimental data. Since the major application of {\sc dpmjet} is the simulation of cosmic ray-induced air showers, the version of the code integrated in the CORSIKA simulation package has been used for the comparison. Wherever necessary, adjustments have been made to improve agreement between simulation and data. With the availability of new muon/neutrino detectors that combine a large fiducial volume with large amounts of shielding, investigation of prompt muons and neutrinos from cosmic ray interactions will be feasible for the first time. Furthermore, above $\gtrsim 100$ TeV charmed particle decay becomes the dominant background for diffuse extraterrestrial neutrino flux searches. A reliable method to simulate charm production in high-energy proton-nucleon interactions is therefore required.Comment: 10 pages, to be published in JCA