1,315 research outputs found

    Childhood Cancer Survival in the Highly Vulnerable Population of South Texas: Persistent Challenges for Adolescents and Hispanic Ethnicity

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    Background: This study examines childhood cancer survival rates and prognostic factors related to survival in the majority Hispanic population of South Texas (STX), whereas most other population studies in childhood cancer survival focus on populations with relatively few Hispanics. Methods: The population-based cohort study used Texas Cancer Registry data (1995-2017) to examine survival and prognostic factors. Results: The 5-year relative survival rate for STX cancer patients diagnosed at 0–19 years was 80.3% for all races/ethnicity. Hispanics had statistically significant lower 5-year relative survival rates than non-Hispanic Whites (NHW) for male and female together diagnosed at age ≥ 5 years. When comparing survival among Hispanics and NHW for the most common cancer, acute lymphocytic leukemia (ALL), the difference was most striking in the 15-19 years age range, with 47.7% Hispanic patients surviving at 5 years compared to 78.4% of NHW counterparts. The multivariable-adjusted analysis showed that males [hazard ratio (HR): 1.13], patients diagnosed at age \u3c 1 year (HR: 1.69), at 10–14 year (HR: 1.42), or at 15–19 years (HR: 1.40), and Hispanics (HR: 1.38) had significantly increased mortality risk compared to the corresponding counterparts for all cancers. Conclusions: STX Hispanics had lower 5-year relative survival than NHW especially for ALL. Male gender, diagnosis at age \u3c 1 year or 10–19 years were also associated with decreased childhood cancer survival. Despite advances in treatment, Hispanics lag significantly behind NHW. Further cohort studies in STX are warranted to identify additional factors affecting survival and to develop interventional strategies

    Short-range oscillators in power-series picture

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    A class of short-range potentials on the line is considered as an asymptotically vanishing phenomenological alternative to the popular confining polynomials. We propose a method which parallels the analytic Hill-Taylor description of anharmonic oscillators and represents all our Jost solutions non-numerically, in terms of certain infinite hypergeometric-like series. In this way the well known solvable Rosen-Morse and scarf models are generalized.Comment: 23 pages, latex, submitted to J. Phys. A: Math. Ge

    Connection Between Type A and E Factorizations and Construction of Satellite Algebras

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    Recently, we introduced a new class of symmetry algebras, called satellite algebras, which connect with one another wavefunctions belonging to different potentials of a given family, and corresponding to different energy eigenvalues. Here the role of the factorization method in the construction of such algebras is investigated. A general procedure for determining an so(2,2) or so(2,1) satellite algebra for all the Hamiltonians that admit a type E factorization is proposed. Such a procedure is based on the known relationship between type A and E factorizations, combined with an algebraization similar to that used in the construction of potential algebras. It is illustrated with the examples of the generalized Morse potential, the Rosen-Morse potential, the Kepler problem in a space of constant negative curvature, and, in each case, the conserved quantity is identified. It should be stressed that the method proposed is fairly general since the other factorization types may be considered as limiting cases of type A or E factorizations.Comment: 20 pages, LaTeX, no figure, to be published in J. Phys.

    The SPHERE data center: a reference for high contrast imaging processing

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    The objective of the SPHERE Data Center is to optimize the scientific return of SPHERE at the VLT, by providing optimized reduction procedures, services to users and publicly available reduced data. This paper describes our motivation, the implementation of the service (partners, infrastructure and developments), services, description of the on-line data, and future developments. The SPHERE Data Center is operational and has already provided reduced data with a good reactivity to many observers. The first public reduced data have been made available in 2017. The SPHERE Data Center is gathering a strong expertise on SPHERE data and is in a very good position to propose new reduced data in the future, as well as improved reduction procedures.Comment: SF2A proceeding

    The Railway Line Frequency and Size Setting Problem

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    [EN] The problem studied in this paper takes as input data a set of lines forming a railway network, and an origin¿destination (OD) matrix. The OD pairs may use either the railway network or an alternative transportation mode. The objective is to determine the frequency/headway of each line as well as its number of carriages, so that the net profit of the railway network is maximized. We propose a mixed integer non-linear programming formulation for this problem. Because of the computational intractability of this model, we develop four algorithms: a mixed integer linear programming (MIP) model, a MIP-based iterative algorithm, a shortest-path based algorithm, and a local search. These four algorithms are tested and compared over a set of randomly generated instances. An application over a case study shows that only the local search heuristic is capable of dealing with large instances.This research was partly funded by the Canadian Natural Sciences and Engineering Research Council under Grant 2015-06189, by the Ministerio de Economía y Competitividad (Spain)/FEDER under projects MTM2012-37048, MTM2015-67706-P and DPI2012-36243-C02-01, and by Junta de Andalucía (Spain)/FEDER under excellence project P10-FQM-5849. Part of this research was done while Federico Perea was enjoying a research visit to CIRRELT, funded by the Universitat Politècnica de València, under program PAID-00-15. This support is gratefully acknowledged. Thanks are due to the referees for their valuable comments.De-Los-Santos, A.; Laporte, G.; Mesa, JA.; Perea Rojas Marcos, F. (2017). The Railway Line Frequency and Size Setting Problem. Public Transport. 9(1-2):33-53. https://doi.org/10.1007/s12469-017-0154-2S335391-2Albrecht T (2009) Automated timetable design for demand-oriented service on suburban railways. Public Transport 1(1):5–20Caprara A, Kroon L, Monaci M, Peeters M, Toth P (2007) Passenger Railway optimization. In: Barnhart C, Laporte G (eds) Handbooks in operations research and management science, vol 14. Transportation, chapter 3. North-Holland, Amsterdam, pp 129–187De-Los-Santos A, Laporte G, Mesa J, Perea F (2014) Simultaneous frequency and capacity setting in uncapacitated metro lines in presence of a competing mode. Transp Res Proc 3:289–298Desaulniers G, Hickman M (2007) Public transport. In: Barnhart C, Laporte G (eds) Handbook in operations research and management science, vol 14, Transportation, chapter 2. North-Holland, Amsterdam, pp 69–127Gallo M, Montella B, D’Acierno L (2011) The transit network design problem with elastic demand and internalisation of external costs: An application to rail frequency optimisation. Transp Res Part C Emerg Technol 19(6):1276–1305Laporte G, Marín A, Mesa JA, Perea F (2011) Designing robust rapid transit networks with alternative routes. J Adv Transp 45(1):54–65Marín A, García-Ródenas R (2009) Location of infrastructure in urban railway networks. Comput Oper Res 36(5):1461–1477Michaelis M, Schöbel A (2009) Integrating line planning, timetable, and vehicle scheduling: a customer oriented heuristic. Public Transport 1(3):211–232Perea F, Mesa JA, Laporte G (2014) Adding a new station and a road link to a road-rail network in the presence of modal competition. Transp Res Part B Methodol 68:1–16Schmidt M, Schöbel A (2015) The complexity of integrating passenger routing decisions in public transportation models. Networks 65(3):228–243Schmidt ME (2014) Integrating routing decisions in public transportation problems. Springer, New YorkSchöbel A (2012) Line planning in public transportation. OR Spectrum 34:491–510van Oort N, van Nes R (2009) Regularity analysis for optimizing urban transit network design. Public Transport 1(2):155–168Vuchic VR (2005) Urban transit: operations, planning, and economics. Wiley, Hoboken, New Jerse

    Dietary Fat Patterns and Outcomes in Acute Pancreatitis in Spain

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    Background/Objective: Evidence from basic and clinical studies suggests that unsaturated fatty acids (UFAs) might be relevant mediators of the development of complications in acute pancreatitis (AP). Objective: The aim of this study was to analyze outcomes in patients with AP from regions in Spain with different patterns of dietary fat intake. Materials and Methods: A retrospective analysis was performed with data from 1,655 patients with AP from a Spanish prospective cohort study and regional nutritional data from a Spanish cross-sectional study. Nutritional data considered in the study concern the total lipid consumption, detailing total saturated fatty acids, UFAs and monounsaturated fatty acids (MUFAs) consumption derived from regional data and not from the patient prospective cohort. Two multivariable analysis models were used: (1) a model with the Charlson comorbidity index, sex, alcoholic etiology, and recurrent AP; (2) a model that included these variables plus obesity. Results: In multivariable analysis, patients from regions with high UFA intake had a significantly increased frequency of local complications, persistent organ failure (POF), mortality, and moderate-to-severe disease in the model without obesity and a higher frequency of POF in the model with obesity. Patients from regions with high MUFA intake had significantly more local complications and moderate-to-severe disease; this significance remained for moderate-to-severe disease when obesity was added to the model. Conclusions: Differences in dietary fat patterns could be associated with different outcomes in AP, and dietary fat patterns may be a pre-morbid factor that determines the severity of AP. UFAs, and particulary MUFAs, may influence the pathogenesis of the severity of AP
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