Constructing Krall-Hahn orthogonal polynomials

Given a sequence of polynomials $(p_n)_n$, an algebra of operators $\mathcal A$ acting in the linear space of polynomials and an operator $D_p\in \mathcal A$ with $D_p(p_n)=\theta_np_n$, where $\theta_n$ is any arbitrary eigenvalue, we construct a new sequence of polynomials $(q_n)_n$ by considering a linear combination of $m+1$ consecutive $p_n$: $q_n=p_n+\sum_{j=1}^m\beta_{n,j}p_{n-j}$. Using the concept of $\mathcal{D}$-operator, we determine the structure of the sequences $\beta_{n,j}, j=1,\ldots,m,$ in order that the polynomials $(q_n)_n$ are eigenfunctions of an operator in the algebra $\mathcal A$. As an application, from the classical discrete family of Hahn polynomials we construct orthogonal polynomials $(q_n)_n$ which are also eigenfunctions of higher-order difference operators.Comment: 26 pages. arXiv admin note: text overlap with arXiv:1307.1326, arXiv:1407.697

Infected pancreatic necrosis: outcomes and clinical predictors of mortality. A post hoc analysis of the MANCTRA-1 international study

: The identification of high-risk patients in the early stages of infected pancreatic necrosis (IPN) is critical, because it could help the clinicians to adopt more effective management strategies. We conducted a post hoc analysis of the MANCTRA-1 international study to assess the association between clinical risk factors and mortality among adult patients with IPN. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality. We identified 247 consecutive patients with IPN hospitalised between January 2019 and December 2020. History of uncontrolled arterial hypertension (p = 0.032; 95% CI 1.135-15.882; aOR 4.245), qSOFA (p = 0.005; 95% CI 1.359-5.879; aOR 2.828), renal failure (p = 0.022; 95% CI 1.138-5.442; aOR 2.489), and haemodynamic failure (p = 0.018; 95% CI 1.184-5.978; aOR 2.661), were identified as independent predictors of mortality in IPN patients. Cholangitis (p = 0.003; 95% CI 1.598-9.930; aOR 3.983), abdominal compartment syndrome (p = 0.032; 95% CI 1.090-6.967; aOR 2.735), and gastrointestinal/intra-abdominal bleeding (p = 0.009; 95% CI 1.286-5.712; aOR 2.710) were independently associated with the risk of mortality. Upfront open surgical necrosectomy was strongly associated with the risk of mortality (p < 0.001; 95% CI 1.912-7.442; aOR 3.772), whereas endoscopic drainage of pancreatic necrosis (p = 0.018; 95% CI 0.138-0.834; aOR 0.339) and enteral nutrition (p = 0.003; 95% CI 0.143-0.716; aOR 0.320) were found as protective factors. Organ failure, acute cholangitis, and upfront open surgical necrosectomy were the most significant predictors of mortality. Our study confirmed that, even in a subgroup of particularly ill patients such as those with IPN, upfront open surgery should be avoided as much as possible. Study protocol registered in ClinicalTrials.Gov (I.D. Number NCT04747990)

Historia comica de la conquista de Sevilla por el Santo Rey Don Fernando, dedicada a ... Doña María Antonia Fernanda ...

A 250/161(07

The Asymmetric Total Synthesis of Cinbotolide: A Revision of the Original Structure

The structure 3,4-dihydroxy-2,4,6,8-tetramethyldec-8-enolide (<b>1</b>) was assigned to a metabolite of <i>Botrytis cinerea</i>, but the spectra of several synthetic analogues had significant differences from that of <b>1</b>. Examination of the constituents of a <i>B. cinerea</i> mutant that overproduces polyketides gave sufficient quantities of <b>1</b>, now named cinbotolide, for chemical transformations. These led to a revised γ-butyrolactone structure for the metabolite. This structure has been confirmed by an asymmetric total synthesis, which also established its absolute configuration

pH-Responsive Delivery of Doxorubicin from Citrate–Apatite Nanocrystals with Tailored Carbonate Content

In this work, the efficiency of bioinspired citrate-functionalized nanocrystalline apatites as nanocarriers for delivery of doxorubicin (DOXO) has been assessed. The nanoparticles were synthesized by thermal decomplexing of metastable calcium/citrate/phosphate solutions both in the absence (Ap) and in the presence (cAp) of carbonate ions. The presence of citrate and carbonate ions in the solution allowed us to tailor the size, shape, carbonate content, and surface chemistry of the nanoparticles. The drug-loading efficiency of the two types of apatite was evaluated by means of the adsorption isotherms, which were found to fit a Langmuir–Freundlich behavior. A model describing the interaction between apatite surface and DOXO is proposed from adsorption isotherms and ζ-potential measurements. DOXO is adsorbed as a dimer by means of a positively charged amino group that electrostatically interacts with negatively charged surface groups of nanoparticles. The drug-release profiles were explored at pHs 7.4 and 5.0, mimicking the physiological pH in the blood circulation and the more acidic pH in the endosome-lysosome intracellular compartment, respectively. After 7 days at pH 7.4, cAp-DOXO released around 42% less drug than Ap-DOXO. However, at acidic pH, both nanoassemblies released similar amounts of DOXO. <i>In vitro</i> assays analyzed by confocal microscopy showed that both drug-loaded apatites were internalized within GTL-16 human carcinoma cells and could release DOXO, which accumulated in the nucleus in short times and exerted cytotoxic activity with the same efficiency. cAp are thus expected to be a more promising nanocarrier for experiments <i>in vivo</i>, in situations where intravenous injection of nanoparticles are required to reach the targeted tumor, after circulating in the bloodstream

Memorias I Congreso Internacional. Universidad, desarrollo y cooperación

La participación de la Universidad Politécnica Salesiana, representada por su Rector, en el III Congreso sobre Universidad, Cooperación y Desarrollo, en Madrid, abril de 2006, la publicación n. 8 de la revista Universitas dedicada al tema ¿Qué cooperación para qué desarrollo? y una experiencia generalizada tanto en Ecuador como en América latina de la urgente necesidad de repensar y replantear la Cooperación Internacional desde los Desarrollos Nacionales, fueron los tres precedentes principales para la organización del I Congreso sobre Uni-versidad, Desarrollo y Cooperación. A la iniciativa de organizar dicho Congreso en Cuenca, con motivo de las celebraciones de los 450 años de fundación de la ciudad, junto con la Universidad Politécnica Salesiana, se unieron la Universidad de Cuenca, Universidad del Azuay, Universidad Particular Técnica de Loja, Universidad Santa María de Guayaquil y el Fondo Ecuatoriano Populorum Progressio FEPP. Todo el proyecto contó con el apoyo financiero del Municipio de Cuenca, del Consejo Provincial del Azuay, la Agencia Española de Cooperación Internacional, y de las Universidades participantes. Así mismo el Congreso se benefició del apoyo académico de la Universidad de Murcia. Las tres Conferencias que enmarcaron el Congreso, coincidieron desde enfoques diferentes en una misma estimación de las relaciones entre Cooperación Internacional y Desarrollo Nacional. José de Souza, a partir de la problemática y experiencia de un desarrollo posible en América Latina, hizo un balance crítico no sólo de la Cooperación Internacional respecto de dicho desarrollo, sino también de las relaciones entre países desarrollados y subdesarrollados. Alfonso Moro, tomando como referencia principal las políticas y programas de la cooperación europea con América Latina, puso de manifiesto las relaciones de desigualdad y dependencia impuestas por dicha cooperación, las cuales condicionan y limitan las reales posibilidades de desarrollos autónomos y sostenidos en los países latinoamericanos