Using Computer Algebra Packages to Complement the Spreadsheet Construction of Binomial Option Trees: The Example of Mathcad

In this paper we show how the mathematical programming package Mathcad can be used to complement the construction of a binomial option tree in Excel. A binomial option tree is first constructed in Excel using standard spreadsheet 'cut and paste' operations. The same binomial tree is then constructed in Mathcad. We conclude that spreadsheet construction of the tree provides students with a sound concept of the underlying mechanics of the option tree. Additionally, the Mathcad construction reinforces the mathematical notation found in many option pricing texts (e.g. summation signs and indices) and allows for the construction of a more flexible lattice that may be easily altered (e.g. the number of steps). In the process students are provided with an understanding of how to construct option trees in the increasingly important world of computer algebra packages.

Bacteriemia secundaria a balanitis por pseudomona aeruginosa XDR en paciente con LLC con inmunosupresión severa prolongada

PB-071 Introducción: La neutropenia severa (7- 10 días) es indicación de profilaxis antibiótica en pacientes de alto riesgo para desarrollo de infección según guías de recomendación. En enfermedades con clonalidad linfoide como la leucemia linfática crónica (LLC), se añade frecuentemente el desarrollo de hipogamaglobulinemia, que produce afectación de la inmunidad innata y humoral, aumentando el riesgo infeccioso de base. Caso clínico: Paciente de 70 años con antecedentes de colicitis ulcerosa (CU) y LLC estadío Rai 4 Binet C desde mayo de 2017, con cadena pesada de las inmunoglobulinas y p53 normales, que recibió Ibrutinib durante 20 días en diciembre de 2017, suspendiéndose por múltiples complicaciones infecciosas: NAC, bacteriemia por E. Coli, gripe A y aspergilosis pulmonar invasiva. Ingresa en hematología en abril de 2018 por diarrea, disuria y balanitis prepucial de una semana de evolución. Presenta fiebre en contexto de neutropenia severa y prolongada, con posible foco infeccioso digestivo y/o urinario. Se inicia tratamiento antibiótico empírico y se continúa tratamiento antifúngico previo. Digestivo descarta que la diarrea sea secundaria a brote de CU. Presenta mejoría de cuadro diarreico con empeoramiento de balanitis, documentándose tándose aislamiento de P. aeruginosa XDR en orina y exudado uretral. Se realizó cambio de antibiótico a aztreonam y colistina según antibiograma recogido en Tabla 1. Durante la evolución, se reactiva infección por CMV y se decide inicio de valganciclovir sin evidencia de lesión orgánica o enfermedad por CMV. Se descarta infección fúngica invasiva activa durante la hospitalización. Debido a progresión clínica de adenopatías y aumento de hepatoesplenomegalia, además de neutropenia persistente, secundarios a infiltración por LLC; se decide inicio de quimioterapia con esquema R-Clorambucilo y reinicio de G-CSF (G-CSF inefectivo en ingresos previos). Se descarta transformación de hemopatía de base mediante biopsia de médula ósea. Se produce reducción importante de adenopatías axilares e inguinales con menor respuesta del conglomerado adenopático abdominal. ..

Glomerulonefritis membranoproliferativa paraneoplásica en leucemia linfática crónica: a propósito de un caso

PB-070 Introducción: La leucemia linfática crónica (LLC) es una neoplasia hematológica con alta incidencia en la población general. Sin embargo, la incidencia de afectación extranodal o extramedular secundaria a procesos paraneoplásicos es rara. En las series de casos encontradas en la literatura, la incidencia de afectación sintomática a nivel genitourinario o ginecológico es inferior al 10%, pero en autopsias se ha encontrado infiltración asintomática hasta en un 90% de los casos. La glomerulonefritis membranoproliferativa (GNMP) es la afectación paraneoplásica más frecuentemente encontrada a nivel renal y se presenta generalmente con insuficiencia renal o síndrome nefrótico. Caso clínico: Paciente de 81 años con antecedentes de HTA, dislipemia, fibrilación auricular, HBP e hipoacusia crónica. Ingresa en Nefrología en septiembre de 2018 por insuficiencia renal progresiva desde una creatinina basal de 1.26 mg/dL hasta 2.54 mg/dL, asociado a microhematuria y proteinuria; sin proceso intercurrente ni exposición a nefrotóxicos. Se encuentra asintomático, sin hallazgos patológicos a la exploración física. Se objetiva proteinuria de 7.7 gramos en orina de 24 horas, proteinuria de Bence Jones negativa y hematuria persistente. Así mismo, se objetiva una linfocitosis de 5.8x103/microL. Se completa el estudio etiológico mediante biopsia renal, con el diagnóstico de GNMP. En las pruebas de inmunohistoquímica, se objetiva un infiltrado linfocítico en cápsula renal CD20 positivo, CD23 y CD5 focalmente positivos; compatible con infiltración por LLC. En la citometría de flujo de sangre periférica, se halla un 38, 1% de linfocitos B maduros, siendo un 96% elementos clonales con inmunofenotipo de LLC con coexpresión de CD20, CD19, CD23, CD200 y CD5. En la citogenética se obtiene trisomía del cromosoma 12. Presenta biología molecular no mutada para TP53 y VH. En la serie ósea no se objetivan imágenes osteolíticas. En diciembre de 2018, Nefrología inicia tratamiento con ..

ELISA versus PCR for diagnosis of chronic Chagas disease: systematic review and meta-analysis

<p>Abstract</p> <p>Background</p> <p>Most current guidelines recommend two serological tests to diagnose chronic Chagas disease. When serological tests are persistently inconclusive, some guidelines recommend molecular tests. The aim of this investigation was to review chronic Chagas disease diagnosis literature and to summarize results of ELISA and PCR performance.</p> <p>Methods</p> <p>A systematic review was conducted searching remote databases (MEDLINE, LILACS, EMBASE, SCOPUS and ISIWeb) and full texts bibliography for relevant abstracts. In addition, manufacturers of commercial tests were contacted. Original investigations were eligible if they estimated sensitivity and specificity, or reliability -or if their calculation was possible - of ELISA or PCR tests, for chronic Chagas disease.</p> <p>Results</p> <p>Heterogeneity was high within each test (ELISA and PCR) and threshold effect was detected only in a particular subgroup. Reference standard blinding partially explained heterogeneity in ELISA studies, and pooled sensitivity and specificity were 97.7% [96.7%-98.5%] and 96.3% [94.6%-97.6%] respectively. Commercial ELISA with recombinant antigens studied in phase three investigations partially explained heterogeneity, and pooled sensitivity and specificity were 99.3% [97.9%-99.9%] and 97.5% [88.5%-99.5%] respectively. ELISA's reliability was seldom studied but was considered acceptable. PCR heterogeneity was not explained, but a threshold effect was detected in three groups created by using guanidine and boiling the sample before DNA extraction. PCR sensitivity is likely to be between 50% and 90%, while its specificity is close to 100%. PCR reliability was never studied.</p> <p>Conclusions</p> <p>Both conventional and recombinant based ELISA give useful information, however there are commercial tests without technical reports and therefore were not included in this review. Physicians need to have access to technical reports to understand if these serological tests are similar to those included in this review and therefore correctly order and interpret test results. Currently, PCR should not be used in clinical practice for chronic Chagas disease diagnosis and there is no PCR test commercially available for this purpose. Tests limitations and directions for future research are discussed.</p

The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in July 2014. It pursues three core programs: APOGEE-2,MaNGA, and eBOSS. In addition, eBOSS contains two major subprograms: TDSS and SPIDERS. This paper describes the first data release from SDSS-IV, Data Release 13 (DR13), which contains new data, reanalysis of existing data sets and, like all SDSS data releases, is inclusive of previously released data. DR13 makes publicly available 1390 spatially resolved integral field unit observations of nearby galaxies from MaNGA,the first data released from this survey. It includes new observations from eBOSS, completing SEQUELS. In addition to targeting galaxies and quasars, SEQUELS also targeted variability-selected objects from TDSS and X-ray selected objects from SPIDERS. DR13 includes new reductions ofthe SDSS-III BOSS data, improving the spectrophotometric calibration and redshift classification. DR13 releases new reductions of the APOGEE-1data from SDSS-III, with abundances of elements not previously included and improved stellar parameters for dwarf stars and cooler stars. For the SDSS imaging data, DR13 provides new, more robust and precise photometric calibrations. Several value-added catalogs are being released in tandem with DR13, in particular target catalogs relevant for eBOSS, TDSS, and SPIDERS, and an updated red-clump catalog for APOGEE.This paper describes the location and format of the data now publicly available, as well as providing references to the important technical papers that describe the targeting, observing, and data reduction. The SDSS website, http://www.sdss.org, provides links to the data, tutorials and examples of data access, and extensive documentation of the reduction and analysis procedures. DR13 is the first of a scheduled set that will contain new data and analyses from the planned ~6-year operations of SDSS-IV.PostprintPeer reviewe

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Measurement of the energy asymmetry in t(t)over-barj production at 13 TeV with the ATLAS experiment and interpretation in the SMEFT framework

A measurement of the energy asymmetry in jet-associated top-quark pair production is presented using $$139\,{\mathrm {fb}}^{-1}$$ 139 fb - 1 of data collected by the ATLAS detector at the Large Hadron Collider during pp collisions at $$\sqrt{s}=13\,\text {TeV}$$ s = 13 TeV . The observable measures the different probability of top and antitop quarks to have the higher energy as a function of the jet scattering angle with respect to the beam axis. The energy asymmetry is measured in the semileptonic $$t{\bar{t}}$$ t t ¯ decay channel, and the hadronically decaying top quark must have transverse momentum above $$350\,\text {GeV}$$ 350 GeV . The results are corrected for detector effects to particle level in three bins of the scattering angle of the associated jet. The measurement agrees with the SM prediction at next-to-leading-order accuracy in quantum chromodynamics in all three bins. In the bin with the largest expected asymmetry, where the jet is emitted perpendicular to the beam, the energy asymmetry is measured to be $$-0.043\pm 0.020$$ - 0.043 ± 0.020 , in agreement with the SM prediction of $$-0.037\pm 0.003$$ - 0.037 ± 0.003 . Interpreting this result in the framework of the Standard Model effective field theory (SMEFT), it is shown that the energy asymmetry is sensitive to the top-quark chirality in four-quark operators and is therefore a valuable new observable in global SMEFT fits