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Uno de los problemas más graves que encuentran los alumnos de los primeros cursos de las licenciaturas de Economía y Administración y Dirección de Empresas consiste en que no logran enfrentarse con confianza a las asignaturas cuantitativas, especialmente las Matemáticas y la Estadística. En esta comunicación nos centramos, especialmente, en el proceso de enseñanza-aprendizaje de la última materia y pretendemos presentar las líneas propuestas en nuestro Departamento para hacer la Estadística una materia más comprensible, atractiva y cercana a los alumnos y para que éstos estén más motivados en su estudio, ayudados por una herramienta interactiva de trabajo, diseñada por los autores, que también se describe en este artículo. Como las nuevas tecnologías se introducen cada vez más en el ámbito educativo, en este trabajo se presenta un programa de software que permite a los alumnos aprender Estadística de una manera más divertida y didáctica, pues el programa consiste en un juego de ordenador, de interfaz muy fácil y muy atractivo en su presentación.

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Abstract: Molecular dynamics simulations were carried out to determine the self-diffusivities of CH4 and CO2 both for pure components and in 50–50 mixtures for a range of molar loadings in MFI, CHA and DDR zeolites. In CHA and DDR zeolites, that consist of cages separated by narrow windows, the inter-cage hopping of molecules occur practically independent of one another and, consequently, the diffusivities of pure components are the same as in the mixture. In sharp contrast, in MFI that consists of intersecting channels, the more mobile species is slowed down significantly in the mixture. [Copyright &y& Elsevier]

The term food loss and waste (FLW) refers to discarded food during the different stages of the food chain. Food loss occurs during the initial stages of the food chain, and food waste occurs during the final stages. The relation between FLW and circular economy (CE) is particularly important for countries which are beginning to implement actions or regulations on this topic. These proposals may have an impact in strategic sectors of their economy. The objective of this review document was to analyse the regulations of FLW and CE in some countries located throughout the European Union, Asia, Africa and Latin America. To fulfil this objective, FLW and CE regulations were identified and analysed in 12 countries located in the aforementioned regions. The analysis showed that France, Spain, Japan and Uruguay included objectives related to FLW in their CE legislations focusing on food waste reduction, whereas China, Chile, Argentina and Mexico did not include FLW in their CE legislations. African countries did not have CE legislations in place yet. France and Japan have had more success in the reduction of FLW. In conclusion, CE regulation should include FLW regulation to achieve more efficiency at reducing and reusing these residues., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Introduction and Importance: Acquired von Willebrand disease (AvWD) is a rare underdiagnosed bleeding disorder caused by alterations in the levels of the major blood-clotting protein von Willebrand factor (vWF). The clinical and laboratory parameters of AvWD are similar to congenital vWD, but it is found in individuals with no positive family history with no underlying genetic basis. The disease remains multifactorial and incompletely understood. Proposed mechanisms include the development of autoantibodies to vWF, absorption of high molecular weight vWF multimers that impair normal function, shear stress induced vWF cleavage and increased proteolysis.The aetiology of the disease is variable, the most common being hematoproliferation, lymophoproliferation, myeloproliferation and autoimmune and cardiovascular disorders. Consensus and protocols for AvWD patients that require major surgery are currently lacking. Patients with AvWD can experience thrombotic events during surgery as a result of therapeutic interactions with pro-thrombotic risk factors., Case Presentation: Here, the authors report a patient with AvWD requiring a knee prosthesis implantation due to chronic pain, limited range of motion and functional impairment. The patient had a high risk of bleeding during surgery and was at risk of thrombosis due to age and obesity., Clinical Discussion: Perioperative care required a collaborative approach and the management of bleeding. The patient was administered vWF concentrate Willfact lacking Factor VIII to prevent haemorrhage and to minimize the risk of thrombosis., Conclusion: The treatment was effective and well-tolerated. The authors use this information to provide recommendations for AvWD patients for whom major surgery is indicated., Competing Interests: M.T.Á.-R. has participated as a speaker in advisory boards and sponsored symposia with Novo Nordisk, Bayer, Takeda, Roche, Pfizer, Octapharma, Amgen, Novartis, CSL Behring and Sobi. H.d.l.C.-R. has received honoraria for attending symposia/congresses and/or for speaking and/or consulting, and/or funds for research from Pfizer, Roche, Sobi, Novo Nordisk, Takeda and Bayer. V.J.Y. has participated as a speaker in advisory boards and sponsored symposia with Novo Nordisk, Bayer, Takeda, Roche, Pfizer, Octapharma, Amgen, Novartis, CSL Behring and Sobi. The remaining authors declare no conflict of interest.Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Purpose: To assess the correlation between profile and severity deterioration in the neuropsychological assessment and the most affected regions in amyloid PET semiquantification. The influence of vascular risk and other potential confounding factors was also evaluated., Methods: A retrospective, observational, and multicenter study including all patients referred for amyloid PET in daily practice was conducted. Patients underwent neuropsychological assessment, and cognitive decline severity and domain(s) affected were recorded. The patients were grouped according to cognitive impairment (CI) profile and severity: (A) no CI, single-domain amnestic CI, multiple-domain amnestic CI, and nonamnestic CI; and (B) mild CI, moderate and severe dementia. An adapted Framingham Stroke Risk Profile was calculated for each individual. Depression and parkinsonism were also recorded. Standardized quantitative analysis software was used to obtain standardized uptake value ratio (SUVR) values from PET/CT images. The corresponding associations were assessed with the most appropriate statistical tests., Results: One hundred twenty-nine patients were included (62 men, 67 women; 64.67 ± 7.47 years old). Significant differences in global and regional amyloid load were exclusively found in women between non-CI and moderate dementia ( P = 0.006, for total-cerebellum SUVR). Posterior and anterior cingulates and prefrontal cortex best represented CI severity ( P = 0.003, 0.006, and 0.006, respectively). No relationship between the CI profile and the regional amyloid load was shown. A significantly high positive correlation was found between age and vascular risk and between these variables and amyloid load in nearly all regions, especially in women with moderate dementia., Conclusion: Semiquantitative analysis of amyloid PET by SUVR values revealed a significant correlation between amyloid burden and CI severity, although only in women., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background:  Venous thromboembolism (VTE) is a common complication in cancer patients. Much of its morbidity stems from the development of fatal pulmonary embolisms (PE). Little is known about the factors involved in clot stability, with angiogenesis possibly being implicated., Methods:  The database is from the TESEO prospective registry that recruits cancer patients with VTE from 41 Spanish hospitals. Independent validation was conducted in a cohort from the Caravaggio trial. The objective is to evaluate the association between exposure to antiangiogenic therapies and the PE/VTE proportion in oncological patients., Results:  In total, 1,536 subjects were evaluated; 58.4% ( n  = 894) had a PE and 7% ( n  = 108) received antiangiogenic therapy (bevacizumab in 75%). The PE/VTE proportion among antiangiogenic-treated individuals was 77/108 (71.3%) versus 817/1,428 (57.2%) among those receiving other alternative therapies ( p  = 0.004). The effect of the antiangiogenics on the PE/VTE proportion held up across all subgroups except for active smokers or those with chronic obstructive pulmonary disease. Exposure to antiangiogenics was associated with increased PEs, odds ratio (OR) 2.27 (95% CI, 1.42-3.63). In the Caravaggio trial, PE was present in 67% of the individuals treated with antiangiogenics, 50% of those who received chemotherapy without antiangiogenic treatment, and 60% without active therapy ( p  = 0.0016)., Conclusion:  Antiangiogenics are associated with increased proportion of PE in oncological patients with VTE. If an effect on clot stability is confirmed, the concept of thrombotic risk in cancer patients should be reconsidered in qualitative terms., Competing Interests: None declared., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)

Introduction: The aim of this work was to analyze, in an in vitro model, the possible protective effects of ultraviolet- (UV-) or UV/blue-filtering intraocular lens (IOL) under light-emitting diode (LED) lighting conditions., Methods: Ten models of IOLs were evaluated. Light transmission spectrum was recorded from 300 to 800 nm, in steps of 1 nm. Photodamage in vitro model was induced in ARPE-19 cells by blue LED light (465-475 nm). Changes in cell viability and oxidative stress variables were studied to assess the protective effect of IOLs., Results: UV/blue-filtering IOLs models block blue light spectrum in different proportion and UV-filtering IOLs blocking wavelength below 400 nm. However, in vitro study under blue LED light exposure does not show protective effects related with mitochondrial dysfunction and oxidative stress of UV/blue-filtering IOLs., Conclusions: The current in vitro study suggests that UV/blue filtering IOLs are not useful in terms of photoprotection in artificial light conditions. The results obtained indicate that it is needed to give attention to other IOL parameters besides the type of filter, as it seems they could have influence on the protective role., (© 2021 The Author(s). Published by S. Karger AG, Basel.)

Ochratoxin A (OTA) is a mycotoxin that is potentially carcinogenic to humans. Although its mechanism remains unclear, oxidative stress has been recognized as a plausible cause for the potent renal carcinogenicity observed in experimental animals. The effect of OTA on oxidative stress parameters in two cell lines of LLC-PK1 and HK-2 derived from the kidneys of pig and human, respectively, were investigated and compared. We found that the cytotoxicity of OTA on LLC-PK1 and HK-2 cells was dose- and time-dependent in both cell lines. Furthermore, increased intracellular reactive oxygen species (ROS) induced by OTA in both cell lines were observed in a time-dependent manner. Glutathione (GSH) was depleted by OTA at >48 h in HK-2 but not in LLC-PK1 cells. While the mRNA levels of glucose-6-phosphate dehydrogenase (G6PD) and glutathione peroxidase 1 (GPX1) in LLC-PK1 were down-regulated by 0.67- and 0.66-fold, respectively, those of catalase (CAT), glutathione reductase (GSR), and superoxide dismutase 1 (SOD) in HK-2 were up-regulated by 2.20-, 2.24-, and 2.75-fold, respectively, after 72 h exposure to OTA. Based on these results, we conclude that HK-2 cells are more sensitive to OTA-mediated toxicity than LLC-PK1, and OTA can cause a significant oxidative stress in HK-2 as indicated by changes in the parameter evaluated.

Age-related macular degeneration (AMD) causes the degeneration of photoreceptors and retinal cells leading to vision loss in older subjects. Among possible exogenous risk factors, it has been recently proposed that long-term exposure to blue light could aggravate the course of AMD. In the search for therapeutic options, plasma rich in growth factors (PRGF) has been shown to enhance cell antioxidant pathways and protect photoreceptors against the harm produced by blue light, although its mechanism of action remains unknown. One possible mechanism, autophagy, is one of the most conservative cell renewal systems used in eukaryotes to destroy cellular components that have been damaged by some kind of insult. The oxidative stress of exposure to blue light is known to induce cell autophagy. In this study, we examined the combined effects on autophagy of blue light and PRGF in a retinal cell line, ARPE19. In response to treatment with both PRGF and blue light, we detected the modulated expression of autophagy markers such as NF-kB, p62/sqstm1, Atg5, LC3 and Beclin1, and inflammatory markers such as IL1B and IL18. Our findings suggest that PRGF promotes cell autophagy in response to exposure to blue light.

Ochratoxin A (OTA) is a mycotoxin frequently found in raw and processed foods. While it is considered a possible human carcinogen, the mechanism of action remains unclear. OTA has been shown to be hepatotoxic in both in vitro and in vivo models and oxidative stress may be one of the factors contributing to its toxicity. Hence, the effect of OTA on human hepatocellular carcinoma, HepG2 cells, was investigated on oxidative stress parameters. The cytotoxicity of OTA on HepG2 was time- and dose-dependent within a range between 0.1 and 10 µM; while 100 μM of OTA increased the intracellular reactive oxygen species (ROS) in a time-dependent manner. Additionally, the levels of glutathione (GSH) were increased by 9.7% and 11.3% at 10 and 100 nM of OTA, respectively; while OTA at 100 μM depleted GSH by 40.5% after 24 h exposure compared with the control. Finally, the mRNA level of catalase (CAT) was downregulated by 2.33-, 1.92-, and 1.82-fold after cells were treated with 1, 10, and 10 μM OTA for 24 h, respectively; which was linked to a decrease in CAT enzymatic activity. These results suggest that oxidative stress is involved in OTA-mediated toxicity in HepG2 cells.