2,463 research outputs found

    El efecto lunes y el efecto viernes en los chicharros de la bolsa española

    Get PDF
    En este estudio se analiza, por primera vez, el efecto lunes y el efecto viernes en los chicharros de la bolsa española, efectos que han sido situados por diversos estudios a lo largo de la historia como potenciales causantes de la estacionalidad que los mercados bursåtiles acusan. Así, se pretende descubrir si existen diferencias entre los rendimientos de estos días y del resto de días de la semana. Se selecciona una muestra de 7 chicharros y un periodo de 3 años comprendido entre el 2 de enero de 2017 y el 31 de diciembre de 2019. Para ello, se emplea el método estadístico de Kruskal-Wallis, el cual identifica las diferencias habidas entre dos grupos. A partir de este anålisis, no se ha podido determinar la existencia de efecto lunes o efecto viernes en las empresas analizadas.In first place, this research analyzes the Monday Effect and the Friday Effect on the small caps of the Spanish stock market. These effects have been placed by various studies along history, as potential causes of the stock seasonality. So, we tried to discover if there are any differences between the returns obtained on these days and those obtained the rest of the days of the week. We choose a group of seven small caps stocks during a period of three years, from 2nd January 2017 to 31st December 2019. In order to achieve the results, we used the Kruskal-Wallis method, which identifies the differences between the two groups. Finally, the results obtained do not allow us to ensure the existence of Monday Effect or Friday Effect in the analyzed compani

    Prevalence of parents' non-intention to vaccinate their children and adolescents against COVID-19: A comparative analysis in Colombia and Peru

    Get PDF
    "We aimed to estimate the prevalence and factors associated with parents’ non-intention to vaccinate their children and adolescents against COVID-19 in Colombia and Peru. We performed a secondary anal- ysis using a database generated by the University of Maryland and Facebook (Facebook, Inc). We Included adult (18 and over) Facebook users residing in LAC who responded to the survey between May 20, and November 5, 2021. We Included sociodemographic characteristics, comorbidities, mental health, eco- nomic and food insecurity, compliance with mitigation strategies against COVID-19, and practices related to vaccination against this disease. We estimated crude (cPR) and adjusted (aPR) prevalence ratios with their respective 95 %CI. We analyzed a sample of 44,678 adults from Colombia and 24,302 from Peru. The prevalence of parents’ non-intention to vaccinate their children and adolescents against COVID-19 was 7.41 % (n = 3,274) for Colombia and 6.64 % (n = 1,464) for Peru. In Colombia, age above 35 years old, com- pliance with physical distancing, use of masks, having economic insecurity, anxiety symptoms, having a chronic condition or more comorbidities, and being vaccinated were associated with a higher probability of vaccinating children and adolescents against COVID-19. In Peru, female gender, compliance with phys- ical distancing, use of masks, having economic insecurity, anxiety symptoms, having a chronic condition or more comorbidities, having had COVID-19, and being vaccinated were associated with a higher prob- ability of vaccinating children against COVID-19. Living in a town, a village, or a rural area was associated with a higher prevalence of non-intention to vaccinate children and adolescents against COVID-19. About 9 out of 10 parents in Colombia and Peru intend to vaccinate their children and adolescents against COVID-19. This intention is associated with some factors which are similar between the two countries, as well as other factors and variations among the different regions of each country.

    Online Interval Type-2 Fuzzy Extreme Learning Machine Applied to 3D Path Following for Remotely Operated Underwater Vehicles

    Get PDF
    In marine missions that involve 3D path following tasks, the overall goal of Underwater Vehicles (UVs) is the successful completion of a path previously specified by the operator. This implies that the path must be followed by the UV as closely as possible and arrive at a location for collection by a vessel. In this paper, an Online Interval Type-2 Fuzzy Extreme Learning Machine (OIT2-FELM) is suggested to achieve a robust following behaviour along a predefined 3D path using a Remotely Operated Underwater Vehicle (ROV). The proposed machine is a fast sequential learning scheme to the training of a more generalised model of TSK Interval Type-2 Fuzzy Inference Systems (TSK IT2 FISs) equivalent to Single Layer Feedforward Neural Networks (SLFNs). Learning new input data in the OIT2-FELM can be done one-by-one or chunk-by-chunk with a fixed or varying size. The OIT2-FELM is implemented in a hierarchical navigation strategy (HNS) as the main guidance mechanism to infer local control motions and to provide the ROV with the necessary autonomy to complete a predefined 3D path. For local path-planning, the OIT2-FELM performs signal classification for obstacle avoidance and target detection based on data collected by an on-board scan sonar. To evaluate the performance of the proposed OIT2-FELM, two different experiments are suggested. First, a number of benchmark problems in the field of non-linear system identification, regression and classification problems are used. Secondly, a number of experiments to the completion of a predefined 3D path using an ROV is implemented. Compared to other fuzzy strategies, the OIT2-FELM offered two significant capabilities. On the one hand, the OIT2-FELM provides a better treatment of uncertainty and noisy signals in underwater environments while improving the ROV's performance. Secondly, online learning in OIT2-FELM allows continuous knowledge discovery from survey data to infer the surroundings of the ROV. Experiment results to the completion of 3D paths show the effectiveness of the proposed approach to handle uncertainty and produce reasonable classification predictions (∌90.5% accuracy in testing data).</p

    Elevated Cardiac Troponin I in Sepsis and Septic Shock: No Evidence for Thrombus Associated Myocardial Necrosis

    Get PDF
    Elevated cardiac troponin I (cTnI) is frequently observed in patients with severe sepsis and septic shock. However, the mechanisms underlying cTnI release in these patients are still unknown. To date no data regarding coagulation disturbances as a possible mechanism for cTnI release during sepsis are available.Consecutive patients with systemic inflammatory response syndrome (SIRS), sepsis or septic shock without evidence of an acute coronary syndrome were analyzed. Coagulation parameters (clotting time (CT), clot formation time (CFT), maximum clot firmness (MCF), alpha-angle) were assessed in native whole blood samples, and using specific activators to evaluate the extrinsic and intrinsic as well as the fibrin component of the coagulation pathway with the use of rotational thrombelastometry (ROTEM). Thirty-eight patients were included and 22 (58%) were cTnI-positive. Baseline characteristics between TnI-positive and -negative patients were similar. The CT, CFT, MCF and the alpha-angle were similar between the groups with trends towards shorter CT in the extrinsic and fibrin activation.We found no differences in coagulation parameters analyzed with rotational thrombelastometry between cTnI-positive and -negative patients with SIRS, severe sepsis, and septic shock. These findings suggest that pathophysiological mechanisms other than thrombus-associated myocardial damage might play a major role, including reversible myocardial membrane leakage and/or cytokine mediated apoptosis in these patients

    Consumption of Herbal Supplements or Homeopathic Remedies to Prevent COVID-19 and Intention of Vaccination for COVID-19 in Latin America and the Caribbean

    Get PDF
    Users of complementary and alternative medicine (CAM) have a lower intention to receive vaccines. Furthermore, Latin America and the Caribbean (LAC) region are among the most affected areas by the COVID-19 pandemics and present a high proportion of CAM users. Therefore, this study evaluates the association between the consumption of herbal supplements or homeopathic remedies to prevent COVID-19 and the intention to vaccinate against COVID-19 in the LAC region. We conducted a secondary data analysis of a Massachusetts Institute of Technology (MIT) survey with Facebook to assess COVID-19 beliefs, behaviours, and norms. Crude and adjusted prevalence ratios (aPR) with their respective 95% confidence intervals (95% CI) were calculated using generalized linear models of the Poisson family with the log link function. The prevalence of the use of products to prevent COVID-19 was the following: consumption of herbal supplements (7.2%), use of homeopathic remedies (4.8%), and consumption of garlic, ginger, and lemon (11.8%). An association was found between using herbal supplements (19.0% vs. 12.8%; aPR = 1.44; 95% CI: 1.30–1.58), the use of homeopathic remedies (20.3% vs. 12.3%; aPR = 1.58; 95% CI: 1.25–1.98), and the consumption of garlic, ginger, and lemon (18.9% vs. 11.9%; aPR = 1.55; 95% CI: 1.50–1.61) and non-intention to vaccinate against COVID-19. In the LAC population, there is an association between using herbal supplements, using homeopathic remedies and consuming garlic, ginger, and lemon to prevent infection by COVID-19 and non-intention to vaccinate against this disease. Therefore, it is necessary to design targeted strategies for groups that consume these products as preventive measures against COVID-19 to increase vaccination coverage and expand the information regarding transmission and prevention strategies for SARS-CoV-2.Revisión por pare

    Binational reflections on pathways to groundwater security in the Mexico-United States borderlands

    Get PDF
    Shared groundwater resources between Mexico and the United States are facing unprecedented stressors. We reflect on how to improve water security for groundwater systems in the border region. Our reflection begins with the state of groundwater knowledge, and the challenges groundwater resources face from a physical, societal and institutional perspective. We conclude that the extent of ongoing cooperation frameworks, joint and remaining research efforts, from which alternative strategies can emerge, still need to be developed. The way forward offers a variety of cooperation models as the future offers rather complex, shared and multidisciplinary water challenges to the Mexico–US borderlands

    Immune Reconstitution Inflammatory Syndrome and Cytomegalovirus Pneumonia Case Report: Highlights and Missing Links in Classification Criteria and Standardized Treatment

    Get PDF
    Background. Cytomegalovirus (CMV) pulmonary involvement is rarely associated with IRIS; therefore, limited information is available. Case Presentation. Here, we describe the case of a 43-year-old HIV-infected male who developed an unusual case of IRIS after cytomegalovirus (CMV) pneumonia. Clinically there was a progressive and paradoxical worsening of respiratory distress, despite being treated for CMV after initiation with antiretroviral therapy. Chest X-ray revealed disseminated infiltrates in both lungs; chest CT-scan showed generalized lung involvement and mediastinal adenopathy. Pulmonary biopsy confirmed CMV pneumonia with the observation of typical viral inclusions on pneumocytes. Conclusions. CMV pneumonia can be associated with the development of IRIS requiring treatment with immunosuppressant’s and immunomodulatory drugs

    Systemic Type I IFN Inflammation in Human ISG15 Deficiency Leads to Necrotizing Skin Lesions

    Get PDF
    Most monogenic disorders have a primary clinical presentation. Inherited ISG15 deficiency, however, has manifested with two distinct presentations to date: susceptibility to mycobacterial disease and intracranial calcifications from hypomorphic interferon-II (IFN-II) production and excessive IFN-I response, respectively. Accordingly, these patients were managed for their infectious and neurologic complications. Herein, we describe five new patients with six novel ISG15 mutations presenting with skin lesions who were managed for dermatologic disease. Cellularly, we denote striking specificity to the IFN-I response, which was previously assumed to be universal. In peripheral blood, myeloid cells display the most robust IFN-I signatures. In the affected skin, IFN-I signaling is observed in the keratinocytes of the epidermis, endothelia, and the monocytes and macrophages of the dermis. These findings define the specific cells causing circulating and dermatologic inflammation and expand the clinical spectrum of ISG15 deficiency to dermatologic presentations as a third phenotype co-dominant to the infectious and neurologic manifestations.Fil: Martin Fernandez, Marta. Icahn School Of Medicine At Mount Sinai; Estados Unidos. King Saud University; Arabia SauditaFil: Bravo García Morato, María. Instituto de Investigacion del Hospital de la Paz.; EspañaFil: Gruber, Conor. Icahn School Of Medicine At Mount Sinai; Estados Unidos. King Saud University; Arabia SauditaFil: Murias Loza, Sara. Instituto de Investigacion del Hospital de la Paz.; EspañaFil: Malik, Muhammad Nasir Hayat. Twincore; Alemania. University Of Lahore; Países Bajos. Leibniz Universitat Hannover; Alemania. Helmholtz Gemeinschaft; AlemaniaFil: Alsohime, Fahad. King Saud University; Arabia SauditaFil: Alakeel, Abdullah. King Saud University; Arabia SauditaFil: Valdez, Rita. Gobierno de la Ciudad Autónoma de Buenos Aires. Hospital General de Agudos Doctor Cosme Argerich; ArgentinaFil: Buta, Sofija. Icahn School Of Medicine At Mount Sinai; Estados UnidosFil: Buda, Guadalupe. Bitgenia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Biología Celular e Histología; ArgentinaFil: Marti, Marcelo Adrian. Bitgenia; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Biología Celular e Histología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Larralde, Margarita. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; ArgentinaFil: Boisson, Bertrand. L'institut Des Maladies Génétiques Imagine; Francia. The Rockefeller University; Estados Unidos. Universite de Paris; FranciaFil: Feito Rodriguez, Marta. Instituto de Investigacion del Hospital de la Paz.; EspañaFil: Qiu, Xueer. Icahn School Of Medicine At Mount Sinai; Estados UnidosFil: Chrabieh, Maya. L'institut Des Maladies Génétiques Imagine; FranciaFil: Al Ayed, Mohammed. Najran University; Arabia SauditaFil: Al Muhsen, Saleh. King Saud University; Arabia SauditaFil: Desai, Jigar V.. National Institutes of Health; Estados UnidosFil: Ferre, Elise M.N.. National Institutes of Health; Estados UnidosFil: Rosenzweig, Sergio D.. National Institutes of Health; Estados UnidosFil: Amador-Borrero, Blanca. Icahn School Of Medicine At Mount Sinai; Estados UnidosFil: Bravo-Gallego, Luz Yadira. Instituto de Investigacion del Hospital de la Paz.; EspañaFil: Olmer, Ruth. Hannover Medical School; Alemania. German Center for Lung Research; AlemaniaFil: Merkert, Sylvia. Hannover Medical School; Alemania. German Center for Lung Research; AlemaniaFil: Bret, Montserrat. Instituto de Investigacion del Hospital de la Paz.; EspañaFil: Sood, Amika K.. University of North Carolina; Estados UnidosFil: Al-rabiaah, Abdulkarim. King Saud University; Arabia SauditaFil: Temsah, Mohamad Hani. King Saud University; Arabia SauditaFil: Halwani, Rabih. University of Sharjah; Emiratos Arabes UnidosFil: Hernandez, Michelle Marilyn. University of North Carolina; Estados UnidosFil: Pessler, Frank. Twincore; Alemania. Helmholtz Centre for Infection Research; AlemaniaFil: Casanova, Jean Laurent. The Rockefeller University; Estados Unidos. Necker Hospital for Sick Children; Francia. Howard Hughes Medical Institute; Estados Unidos. Universite de Paris; FranciaFil: Bustamante, Jacinta. The Rockefeller University; Estados Unidos. Necker Hospital for Sick Children; Francia. Universite de Paris; FranciaFil: Lionakis, Michail S.. National Institutes of Health; Estados UnidosFil: Bogunovic, Dusan. Icahn School Of Medicine At Mount Sinai; Estados Unido

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

    Get PDF
    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
    • 

    corecore