Advances in Polynomial Optimization

Polynomial optimization has a wide range of practical applications in fields such as optimal control, energy and water networks, facility location, management science, and finance. It also generalizes relevant optimization problems thoroughly studied in the literature, such as mixed-binary linear optimization, quadratic optimization, and complementarity problems. As finding globally optimal solutions is an extremely challenging task, the development of efficient techniques for solving polynomial optimization problems is of particular relevance. In this thesis we provide a detailed study of different techniques to solve this kind of problems and we introduce some nobel approaches in this field, including the use of statistical learning techniques. Furthermore, we also present a practical application of polynomial optimization to finance and more specifically, portfolio design

Protocolo de actuación médica para el tratamiento del hematoma subdural crónico

Hemos leído el reciente trabajo publicado en su revista por A. Barbosa y colaboradores, titulado: "Protocolo de actuación médica para el tratamiento del hematoma subdural crónico" y nos gustaría hacer algún comentario a este, ya que en nuestro Hospital tenemos una larga y amplia experiencia en el tipo de patología investigada.En primer lugar, deseamos felicitar a los autores(as) por la elaboración del protocolo. Consideramos que el hematoma subdural crónico (HSC) es una patología con la suficiente entidad y repercusión social para que exista una guía o protocolo para su diagnóstico, tratamiento y seguimiento, pues en numerosos hospitales no disponemos de ella. No podemos olvidar que Balser y otros calculan que, debido al envejecimiento progresivo de la población, en el año 2030 se operarán en Norteamérica unos 60 000 HSC, situación que contribuirá a aumentar la frecuencia de dicha patología neuroquirúrgica, en nuestra opinión calculamos que podría extenderse a todos los países. Además, el HSC en esta población mayor, tiene niveles altos de mortalidad y reduce de manera notable las expectativas de vida. Nos llama la atención que en la sección introductoria, los autores(as) mencionen a los aneurismas intracraneales rotos o a las malformaciones arteriovenosas cerebrales (MAV) como posibles causas de hematoma subdural crónico. En nuestra serie de este tipo de hematomas y con un número ya cercano a 2 000 pacientes operados, no hemos observado ningún caso de hemorragia subaracnoidea o MAV y se escapa a nuestras observaciones por cuál mecanismo estas patologías puedan dar lugar a los hematomas. Así también, ellos citan a las hemorragias profusas como posibles complicaciones. En nuestra experiencia, solo se han presentado en cuatro casos (0,51 %) y en la reciente revisión de Rahujala y otros, solo representan el 1,1 %. Además, se encuentran por detrás de las recidivas (18 %), las crisis epilépticas (4,8 %), y la infección, con un 3 %.(5) Las complicaciones más frecuentes y que más preocupan por su mayor incidencia en estos pacientes, son la médicas al tratarse de pacientes de edad avanzada en su mayoría, y con múltiples comorbilidades sistémicas

Prediction of Anti-Glioblastoma Drug-Decorated Nanoparticle Delivery Systems Using Molecular Descriptors and Machine Learning

The theoretical prediction of drug-decorated nanoparticles (DDNPs) has become a very important task in medical applications. For the current paper, Perturbation Theory Machine Learning (PTML) models were built to predict the probability of different pairs of drugs and nanoparticles creating DDNP complexes with anti-glioblastoma activity. PTML models use the perturbations of molecular descriptors of drugs and nanoparticles as inputs in experimental conditions. The raw dataset was obtained by mixing the nanoparticle experimental data with drug assays from the ChEMBL database. Ten types of machine learning methods have been tested. Only 41 features have been selected for 855,129 drug-nanoparticle complexes. The best model was obtained with the Bagging classifier, an ensemble meta-estimator based on 20 decision trees, with an area under the receiver operating characteristic curve (AUROC) of 0.96, and an accuracy of 87% (test subset). This model could be useful for the virtual screening of nanoparticle-drug complexes in glioblastoma. All the calculations can be reproduced with the datasets and python scripts, which are freely available as a GitHub repository from authors. View Full-TextThe APC was funded by IKERDATA, S.L. under grant 3/12/DP/2021/00102—Area 1: Development of innovative business projects, from Provincial Council of Vizcaya (BEAZ for the Creation of Innovative Business Innovative business ventures)

Impact of the first wave of the SARS-CoV-2 pandemic on the outcome of neurosurgical patients: A nationwide study in Spain

Objective To assess the effect of the first wave of the SARS-CoV-2 pandemic on the outcome of neurosurgical patients in Spain. Settings The initial flood of COVID-19 patients overwhelmed an unprepared healthcare system. Different measures were taken to deal with this overburden. The effect of these measures on neurosurgical patients, as well as the effect of COVID-19 itself, has not been thoroughly studied. Participants This was a multicentre, nationwide, observational retrospective study of patients who underwent any neurosurgical operation from March to July 2020. Interventions An exploratory factorial analysis was performed to select the most relevant variables of the sample. Primary and secondary outcome measures Univariate and multivariate analyses were performed to identify independent predictors of mortality and postoperative SARS-CoV-2 infection. Results Sixteen hospitals registered 1677 operated patients. The overall mortality was 6.4%, and 2.9% (44 patients) suffered a perioperative SARS-CoV-2 infection. Of those infections, 24 were diagnosed postoperatively. Age (OR 1.05), perioperative SARS-CoV-2 infection (OR 4.7), community COVID-19 incidence (cases/10 5 people/week) (OR 1.006), postoperative neurological worsening (OR 5.9), postoperative need for airway support (OR 5.38), ASA grade =3 (OR 2.5) and preoperative GCS 3-8 (OR 2.82) were independently associated with mortality. For SARS-CoV-2 postoperative infection, screening swab test <72 hours preoperatively (OR 0.76), community COVID-19 incidence (cases/10 5 people/week) (OR 1.011), preoperative cognitive impairment (OR 2.784), postoperative sepsis (OR 3.807) and an absence of postoperative complications (OR 0.188) were independently associated. Conclusions Perioperative SARS-CoV-2 infection in neurosurgical patients was associated with an increase in mortality by almost fivefold. Community COVID-19 incidence (cases/10 5 people/week) was a statistically independent predictor of mortality. Trial registration number CEIM 20/217

Computational advances in polynomial optimization: RAPOSa, a freely available global solver

[Abstract]: In this paper we introduce RAPOSa, a global optimization solver specifically designed for (continuous) polynomial programming problems with box-constrained variables. Written entirely in C++, RAPOSa is based on the Reformulation-Linearization (Sherali and Tuncbilek in J Glob Optim 103:225–249, 1992). We present a description of the main characteristics of RAPOSa along with a thorough analysis of the impact on its performance of various enhancements discussed in the literature, such as bound tightening and SDP cuts. We also present a comparative study with three of the main state-of-the-art global optimization solvers: BARON, Couenne and SCIP.Ministerio de Ciencia y Tecnología; PID2021-124030NB-C32Ministerio de Educación; FPU Grant 17/02643Xunta de Galicia; ED431C-2020-14Xunta de Galicia; ED431G2019/0

Prior flexibility and performance in Tuy-Santiago military test

Introducción: La flexibilidad que tengan las personas, previamente a la realización de una actividad física-deportiva puede influir en los resultados de ésta. Por ello, nos propusimos analizar la influencia del nivel de flexibilidad previo sobre el rendimiento de los militares participantes en la prueba de largo recorrido Tuy-Santiago, edición 2014. Material y Método: Estudio transversal en el que han participado 135 militares voluntarios, con una media de edad de 28,47±4,54 años. Esta prueba deportivo-militar consta de un recorrido aproximado de 120 km, con una serie de pruebas militares realizadas a lo largo del mismo. La flexibilidad fue valorada por medio de la prueba Sit and Reach. Se analizaron las variables usando estadísticos descriptivos y tablas de contingencia, para estudiar las diferencias existentes entre las variables, con el programa estadístico SPSS. Resultados: Existen diferencias significativas entre los valores medios de la de la prueba de flexibilidad entre patrullas antes de comenzar la prueba, además de correlaciones significativas con determinados tramos o pruebas que integraban el recorrido completo. Conclusiones: Parece haber una correlación significativa entre la flexibilidad previa y el rendimiento alcanzado para la muestra analizada en la prueba Tuy-Santiago.Introduction: The flexibility degree of different athletes before any sport event is being suggested to influence the performance in it. Because of that, the objective of this study was to analyze the influence of the previous flexibility degree of the servicemen participating in the military sport event Tuy-Santiago in 2014. Material and Method: Cross sectional study involving 135 voluntary servicemen, with an average age of 28,47±4,54 years. This military sport event has an approximate distance of 120Km, and different military test are included in it. Flexibility has been measured by the Sit and Reach test. Variables have been analyzed using descriptive statistics and crosstabs using the SPSS software. Results: There are significant differences between mean values for flexibility among the patrols. Additionally, significant correlation was observed between flexibility and different parts or test of the event. Conclusions: There seems to be a significant correlation between previous flexibility and the performance achieved in the military sport event Tuy-Santiago for the analyzed sample

Ablation of atrial fibrillation in patients with Brugada syndrome: A systematic review of the literature

Supraventricular arrhythmias are common in Brugada syndrome (BS), and notoriously difficult to manage with medical therapy secondary to associated risks. Pulmonary vein isolation (PVI) is often utilized instead, but its outcomes in this population are not well-known. We aim to provide a holistic evaluation of interventional treatment for Atrial fibrillation (AF) in the BS population. Electronic databases Medline, Embase, Cinahl, Cochrane, and Scopus were systematically searched for publications between 01/01/1995 and 12/31/2017. Studies were screened based on predefined inclusion and exclusion criteria. A total of 49 patients with BS and AF were included. Age range from 28.8 to 64 years, and 77.5% were male. 38 patients were implanted with implantable cardioverter-defibrillators (ICD) at baseline, and of them, 39% suffered inappropriate shocks for rapid AF. 34/49 (69%) of patients achieved remission following a single PVI procedure. Of the remaining, 13 patients underwent one or more repeat ablation procedures. Overall, 45/49 (91.8%) of patients remained in remission during long-term follow-up after one or more PVI procedures in the absence of antiarrhythmic drug (AAD) therapy. Postablation, no patients suffered inappropriate ICD shock. Furthermore, no major complications secondary to PVI occurred in any patient. AF ablation achieves acute and long-term success in the vast majority of patients. It is effective in preventing inappropriate ICD therapy secondary to rapid AF. Complication rates of PVI in BS are low. Thus, in light of the risks of AADs and risk of inappropriate ICD shocks in the BS population, catheter ablation could represent an appropriate first-line therapy for paroxysmal atrial fibrillation in BS patients

Long-term prognosis of patients with life-threatening ventricular arrhythmias induced by coronary artery spasm.

AIMS: Coronary artery spasm (CAS) is associated with ventricular arrhythmias (VA). Much controversy remains regarding the best therapeutic interventions for this specific patient subset. We aimed to evaluate the clinical outcomes of patients with a history of life-threatening VA due to CAS with various medical interventions, as well as the need for ICD placement in the setting of optimal medical therapy. METHODS AND RESULTS: A multicentre European retrospective survey of patients with VA in the setting of CAS was aggregated and relevant clinical and demographic data was analysed. Forty-nine appropriate patients were identified: 43 (87.8%) presented with VF and 6 (12.2%) with rapid VT. ICD implantation was performed in 44 (89.8%). During follow-up [59 (17-117) months], appropriate ICD shocks were documented in 12. In 8/12 (66.6%) no more ICD therapies were recorded after optimizing calcium channel blocker (CCB) therapy. SCD occurred in one patient without ICD. Treatment with beta-blockers was predictive of appropriate device discharge. Conversely, non-dihydropyridine CCB therapy was significantly protective against VAs. CONCLUSION: Patients with life-threatening VAs secondary to CAS are at particularly high-risk for recurrence, especially when insufficient medical therapy is administered. Non-dihydropyridine CCBs are capable of suppressing episodes, whereas beta-blocker treatment is predictive of VAs. Ultimately, in spite of medical intervention, some patients exhibited arrhythmogenic events in the long-term, suggesting that ICD implantation may still be indicated for all