Planet Four: Terrains - Discovery of Araneiforms Outside of the South Polar Layered Deposits

We present the results of a systematic mapping of seasonally sculpted terrains on the South Polar region of Mars with the Planet Four: Terrains (P4T) online citizen science project. P4T enlists members of the general public to visually identify features in the publicly released Mars Reconnaissance Orbiter CTX images. In particular, P4T volunteers are asked to identify: 1) araneiforms (including features with a central pit and radiating channels known as 'spiders'); 2) erosional depressions, troughs, mesas, ridges, and quasi-circular pits characteristic of the South Polar Residual Cap (SPRC) which we collectively refer to as 'Swiss cheese terrain', and 3) craters. In this work we present the distributions of our high confidence classic spider araneiforms and Swiss cheese terrain identifications. We find no locations within our high confidence spider sample that also have confident Swiss cheese terrain identifications. Previously spiders were reported as being confined to the South Polar Layered Deposits (SPLD). Our work has provided the first identification of spiders at locations outside of the SPLD, confirmed with high resolution HiRISE imaging. We find araneiforms on the Amazonian and Hesperian polar units and the Early Noachian highland units, with 75% of the identified araneiform locations in our high confidence sample residing on the SPLD. With our current coverage, we cannot confirm whether these are the only geologic units conducive to araneiform formation on the Martian South Polar region. Our results are consistent with the current CO2 jet formation scenario with the process exploiting weaknesses in the surface below the seasonal CO2 ice sheet to carve araneiform channels into the regolith over many seasons. These new regions serve as additional probes of the conditions required for channel creation in the CO2 jet process. (Abridged)Comment: accepted to Icarus - Supplemental data files are available at https://www.zooniverse.org/projects/mschwamb/planet-four-terrains/about/results - Icarus print version available at http://www.sciencedirect.com/science/article/pii/S001910351730055

BFKL at Next-to-Next-to-Leading Order

We determine an approximate expression for the O(alpha_s^3) contribution chi_2 to the kernel of the BFKL equation, which includes all collinear and anticollinear singular contributions. This is derived using recent results on the relation between the GLAP and BFKL kernels (including running-coupling effects to all orders) and on small-x factorization schemes. We present the result in various schemes, relevant both for applications to the BFKL equation and to small-x evolution of parton distributions.Comment: 34 pages, 6 figures, TeX with harvmac. Various small typos corrects, in particular first term in eq D.3. Final version to be published in Nucl. Phys.

Finite-top-mass effects in NNLO Higgs production

We construct an accurate approximation to the exact NNLO cross section for Higgs production in gluon-gluon fusion by matching the dominant finite top mass corrections recently computed by us to the known result in the infinite mass limit. The ensuing corrections to the partonic cross section are very large when the center of mass energy of the partonic collision is much larger than the Higgs mass, but lead to a moderate correction at the percent level to the total Higgs production cross section at the LHC. Our computation thus reduces the uncertainty related to these corrections at the LHC from the percent to the per mille level.Comment: 4 pages, 4 figures; to be published in the proceedings of QCD2008. Reference adde

Higgs production via gluon-gluon fusion with finite top mass beyond next-to-leading order

We present a computation of the cross section for inclusive Higgs production in gluon-gluon fusion for finite values of the top mass in perturbative QCD to all orders in the limit of high partonic center-of-mass energy. We show that at NLO the high energy contribution accounts for most of the difference between the result found with finite top mass and that obtained in the limit of infinite top mass. We use our result to improve the known NNLO order result obtained with infinite top mass. We estimate the effect of the high energy NNLO top mass dependence on the K factor to be of the order of a few per cent.Comment: 20 pages, 5 figures, latex with epsfi

Jet vetoing at the LHC

We study the effect of a veto on additional jets in the rapidity region between a pair of high transverse momentum jets at the LHC. We aim to sum the most important logarithms in the ratio of the jet transverse momentum to the veto scale and to that end we attempt to assess the significance of the super-leading logarithms that appear at high orders in the perturbative expansion. We also compare our results to those of HERWIG++, in an attempt to ascertain the accuracy of the angular ordered parton shower. We find that there are large corrections that arise for large enough jet transverse momenta as a consequence of Coulomb gluon exchanges.Comment: 25 page

Parton distributions with small-x resummation:evidence for BFKL dynamics in HERA data

We present a determination of the parton distribution functions of the proton in which NLO and NNLO fixed-order calculations are supplemented by NLLx small-x resummation. Deep inelastic structure functions are computed consistently at NLO+NLLx or NNLO+NLLx, while for hadronic processes small-x resummation is included only in the PDF evolution, with kinematic cuts introduced to ensure the fitted data lie in a region where the fixed-order calculation of the hard cross-sections is reliable. In all other respects, the fits use the same methodology and are based on the same global dataset as the recent NNPDF3.1 analysis. We demonstrate that the inclusion of small-x resummation leads to a quantitative improvement in the perturbative description of the HERA inclusive and charm-production reduced cross-sections in the small x region. The impact of the resummation in our fits is greater at NNLO than at NLO, because fixed-order calculations have a perturbative instability at small x due to large logarithms that can be cured by resummation. We explore the phenomenological implications of PDF sets with small-x resummation for the longitudinal structure function $F_L$ at HERA, for parton luminosities and LHC benchmark cross-sections, for ultra-high energy neutrino-nucleus cross-sections, and for future high-energy lepton-proton colliders such as the LHeC.Comment: 70 pages, many figures. Discussion on uncertainties due to subleading logarithmic contributions. Discussion on fits with pseudodata from future high-energy lepton-proton colliders. Updated references. Version to be published in EPJ

Quality of life and burden in carers for persons with Chronic Obstructive Pulmonary Disease receiving oxygen therapy

OBJECTIVE:to assess the quality of life and burden of caregivers to Chronic Obstructive Pulmonary Disease patients on Long-Term Oxygen Therapy and to investigate the factors influencing this burden.METHOD:this is an analytical, cross-sectional study of 80 persons with Chronic Obstructive Pulmonary Disease on Long-Term Oxygen Therapy who used the specialized outpatient center of the Federal University of São Paulo, and their carers. The following instruments were used: Medical Outcomes Studies 36 (SF-36), Caregiver Burden Scale (CBS) and the Katz Index, along with socio-demographic and clinical variables.RESULTS:the most compromised scores on the carers' quality of life questionnaire were for Vitality and Mental Health. On the Caregiver Burden Scale, the domain which created the greatest burden for carers was the Environment. With the exception of Emotional Involvement, all the domains of quality of life were affected negatively by the domains of caregiver burden.CONCLUSION:it was shown that carers' quality of life was compromised and that they were overburdened with care tasks, confirming that assisting persons with Chronic Obstructive Pulmonary Disease is an important element in carers' quality of life.OBJETIVO:evaluar la calidad de vida y la sobrecarga de cuidados experimentada por cuidadores de portadores de la Enfermedad Pulmonar Obstructiva Crónica en uso de Oxigenoterapia Domiciliar Prolongada e investigar los factores que influencian esa sobrecarga.MÉTODO:se trata de estudio transversal analítico, con 80 portadores de la Enfermedad Pulmonar Obstructiva Crónica en uso de Oxigenoterapia Domiciliar en el ambulatorio especializado de la Universidad Federal de São Paulo y de sus respectivos cuidadores, aplicando los instrumentos: Medical Outcomes Studies 36 (SF-36), Caregiver Burden Scale (CBS), índice de Katz y variables sociodemográficas y clínicas.RESULTADOS:los puntajes del cuestionario de calidad de vida de los cuidadores más comprometidos fueron la Vitalidad y la Salud Mental. El Ambiente fue el dominio del Caregiver Burden Scale que generó mayor sobrecarga de cuidados. Con excepción del Envolvimiento Emocional, todos los dominios de calidad de vida fueron influenciados de forma negativa por los dominios de sobrecarga de cuidados.CONCLUSIÓN:se demostró que la calidad de vida y la sobrecarga de cuidados, de los cuidadores, estaban comprometidos, confirmando que cuidar a los portadores de Enfermedad Pulmonar Obstructiva Crónica, es un importante interviniente en la calidad de vida del cuidador.OBJETIVO:avaliar a qualidade de vida e a sobrecarga de cuidados, vivenciada por cuidadores de portadores de Doença Pulmonar Obstrutiva Crônica, em uso de Oxigenoterapia Domiciliar Prolongada, e investigar os fatores que influenciam essa sobrecarga.MÉTODO:trata-se de estudo transversal analítico, com 80 portadores de Doença Pulmonar Obstrutiva Crônica em uso de Oxigenoterapia Domiciliar do ambulatório especializado da Universidade Federal de São Paulo e seus respectivos cuidadores, aplicando-se os instrumentos: Medical Outcomes Studies 36, Caregiver Burden Scale, índice de Katz e variáveis sociodemográficas e clínicas.RESULTADOS:os escores do questionário de qualidade de vida dos cuidadores mais comprometidos foram vitalidade e saúde mental. O ambiente foi o domínio do Caregiver Burden Scale que gerou maior sobrecarga de cuidados. Com exceção do envolvimento emocional, todos os domínios de qualidade de vida foram influenciados de forma negativa pelos domínios de sobrecarga de cuidados.CONCLUSÃO:demonstrou-se comprometimento da qualidade de vida e sobrecarga de cuidados dos cuidadores, confirmando que assistir portadores de Doença Pulmonar Obstrutiva Crônica é um importante interveniente na qualidade de vida do cuidador.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de EnfermagemUniversidade Federal de São Paulo (UNIFESP) Hospital São PauloUNIFESP, Escola Paulista de Enfermagem (EPE)UNIFESP, Hospital São PauloSciEL