Showing papers by "University of Seville published in 2018"

Proposed minimal standards for the use of genome data for the taxonomy of prokaryotes

Abstract: Advancement of DNA sequencing technology allows the routine use of genome sequences in the various fields of microbiology. The information held in genome sequences proved to provide objective and reliable means in the taxonomy of prokaryotes. Here, we describe the minimal standards for the quality of genome sequences and how they can be applied for taxonomic purposes.

Low-gluten, nontransgenic wheat engineered with CRISPR/Cas9.

Abstract: Celiac disease is an autoimmune disorder triggered in genetically predisposed individuals by the ingestion of gluten proteins from wheat, barley, and rye. The -gliadin gene family of wheat contains four highly stimulatory peptides, of which the 33-mer is the main immunodominant peptide in celiac patients. We designed two sgRNAs to target a conserved region adjacent to the coding sequence for the 33-mer in the -gliadin genes. Twenty-one mutant lines were generated, all showing strong reduction in -gliadins. Up to 35 different genes were mutated in one of the lines of the 45 different genes identified in the wild type, while immunoreactivity was reduced by 85%. Transgene-free lines were identified, and no off-target mutations have been detected in any of the potential targets. The low-gluten, transgene-free wheat lines described here could be used to produce low gluten foodstuff and serve as source material to introgress this trait into elite wheat varieties. This article is protected by copyright. All rights reserved.

Aerial Manipulation: A Literature Review

Abstract: Aerial manipulation aims at combining the versatility and the agility of some aerial platforms with the manipulation capabilities of robotic arms. This letter tries to collect the results reached by the research community so far within the field of aerial manipulation, especially from the technological and control point of view. A brief literature review of general aerial robotics and space manipulation is carried out as well.

Fibrosis Severity as a Determinant of Cause-Specific Mortality in Patients With Advanced Nonalcoholic Fatty Liver Disease: A Multi-National Cohort Study

Abstract: Background & Aims Little is known about the natural course of nonalcoholic fatty liver disease (NAFLD) with advanced fibrosis. We describe long-term outcomes and evaluate the effects of clinical and histologic parameters on disease progression in patients with advanced NAFLD. Methods We conducted a multi-national study of 458 patients with biopsy-confirmed NAFLD with bridging fibrosis (F3, n = 159) or compensated cirrhosis (222 patients with Child-Turcotte-Pugh scores of A5 and 77 patients with scores of A6), evaluated from April 1995 through November 2013 and followed until December 2016, death, or liver transplantation at hepatology centers in Spain, Australia, Hong Kong, and Cuba. Biopsies were re-evaluated and scored; demographic, clinical, laboratory, and pathology data for each patient were collected from the time of liver biopsy collection. Cox proportional and competing risk models were used to estimate rates of transplantation-free survival and major clinical events and to identify factors associated with outcomes. Results During a mean follow-up time of 5.5 years (range, 2.7–8.2 years), 37 patients died, 37 received liver transplants, 88 had initial hepatic decompensation events, 41 developed hepatocellular carcinoma, 14 had vascular events, and 30 developed nonhepatic cancers. A higher proportion of patients with F3 fibrosis survived transplantation-free for 10 years (94%; 95% confidence interval [CI], 86%–99%) than of patients with cirrhosis and Child-Turcotte-Pugh A5 (74%; 95% CI, 61%–89%) or Child-Turcotte-Pugh A6 (17%; 95% CI, 6%–29%). Patients with cirrhosis were more likely than patients with F3 fibrosis to have hepatic decompensation (44%; 95% CI, 32%–60% vs 6%, 95% CI, 2%–13%) or hepatocellular carcinoma (17%; 95% CI, 8%–31% vs 2.3%, 95% CI, 1%–12%). The cumulative incidence of vascular events was higher in patients with F3 fibrosis (7%; 95% CI, 3%–18%) than cirrhosis (2%; 95% CI, 0%–6%). The cumulative incidence of nonhepatic malignancies was higher in patients with F3 fibrosis (14%; 95% CI, 7%–23%) than cirrhosis (6%; 95% CI, 2%–15%). Death or transplantation, decompensation, and hepatocellular carcinoma were independently associated with baseline cirrhosis and mild ( Conclusions Patients with NAFLD cirrhosis have predominantly liver-related events, whereas those with bridging fibrosis have predominantly nonhepatic cancers and vascular events.

Targeting stromal remodeling and cancer stem cell plasticity overcomes chemoresistance in triple negative breast cancer

Abstract: The cellular and molecular basis of stromal cell recruitment, activation and crosstalk in carcinomas is poorly understood, limiting the development of targeted anti-stromal therapies. In mouse models of triple negative breast cancer (TNBC), Hedgehog ligand produced by neoplastic cells reprograms cancer-associated fibroblasts (CAFs) to provide a supportive niche for the acquisition of a chemo-resistant, cancer stem cell (CSC) phenotype via FGF5 expression and production of fibrillar collagen. Stromal treatment of patient-derived xenografts with smoothened inhibitors (SMOi) downregulates CSC markers expression and sensitizes tumors to docetaxel, leading to markedly improved survival and reduced metastatic burden. In the phase I clinical trial EDALINE, 3 of 12 patients with metastatic TNBC derived clinical benefit from combination therapy with the SMOi Sonidegib and docetaxel chemotherapy, with one patient experiencing a complete response. These studies identify Hedgehog signaling to CAFs as a novel mediator of CSC plasticity and an exciting new therapeutic target in TNBC.

A quantitative criterion for determining the order of magnetic phase transitions using the magnetocaloric effect

Abstract: The ideal magnetocaloric material would lay at the borderline of a first-order and a second-order phase transition. Hence, it is crucial to unambiguously determine the order of phase transitions for both applied magnetocaloric research as well as the characterization of other phase change materials. Although Ehrenfest provided a conceptually simple definition of the order of a phase transition, the known techniques for its determination based on magnetic measurements either provide erroneous results for specific cases or require extensive data analysis that depends on subjective appreciations of qualitative features of the data. Here we report a quantitative fingerprint of first-order thermomagnetic phase transitions: the exponent n from field dependence of magnetic entropy change presents a maximum of n > 2 only for first-order thermomagnetic phase transitions. This model-independent parameter allows evaluating the order of phase transition without any subjective interpretations, as we show for different types of materials and for the Bean–Rodbell model. Magnetocaloric materials often perform best when their magnetic transitions are at the boundary between first- and second-order behavior. Here the authors propose a simple criterion to determine the order of a transition, which may accelerate future magnetocaloric material searches.

Signaling Pathways in Inflammation and Anti-inflammatory Therapies

Abstract: During the past decade, an abundance of new evidence highlighted the importance of inflammation in the development of chronic pathologies such as neurodegeneration, cancer, diabetes, cardiovascular disease and inflammatory bowel disease. However, most of the current therapies do not address the underlying problem and better therapies are urgently needed. A growing number of researchers have discovered various signaling pathways that are associated with the initiation and progression of inflammation. Among different pathways, we will focus on three classical inflammatory pathways: p38 MAPK, IL-6/JAK/STAT3 and PI3K; and a non-classical inflammatory pathway, the Hippo. Recently, the Hippo pathway has been linked to various inflammatory modulators such as FoxO1/3, TNFα, IL-6, COX2, HIF-1α, AP-1, JAK and STAT. In this review, the molecular mechanisms, associated pathologies and selected drugs (both preclinical and clinical) of these signaling pathways will be summarized. Finally, limitations and potential risks of anti-inflammatory drugs will also be discussed.

Does entrepreneurship education in the first year of higher education develop entrepreneurial intentions? The role of learning and inspiration

Abstract: Drawing on entrepreneurship education (EE) theory, this article examines the role of learning and inspiration in developing students' entrepreneurial intentions in the First Year in Higher Education. This addresses the paucity of research on early university experiences of EE and their influence on entrepreneurial intentions. Using a longitudinal survey of business students at a British university, the authors identify four scenarios related to the participation/non-participation in EE and subsequent increase or decrease of entrepreneurial intentions. A sub-set of those surveyed are interviewed (n = 49) to better understand how their university experience has influenced their entrepreneurial intentions. Findings suggest that the influence of EE is variable, in some cases even leading to a decrease in entrepreneurial intentions. The results contribute to theories of EE and intentions in the early stages of higher education. The authors discuss implications for theory and practice.

Model Predictive Control of Six-Phase Induction Motor Drives Using Virtual Voltage Vectors

Abstract: The most serious and recent competitor to the standard field oriented control for induction motors (IM) is the finite control set model predictive control (FCS-MPC). Nevertheless, the extension to multiphase drives faces the impossibility to simultaneously regulate the flux/torque and the secondary current components (typically termed $x - y$ in the literature). The application of a single switching state during the whole sampling period inevitably implies the appearance of $x - y$ voltage/currents that increase the system losses and deteriorate the power quality. These circulating currents become intolerably high as per the unit $x - y$ impedance and the switching frequency diminish. Aiming to overcome this limitation, this work suggests the integration of virtual voltage vectors (VVs) into the FCS-MPC structure. The VVs ensure null $x - y$ voltages on average during the sampling period and the MPC approach selects the most suitable VV to fulfill the flux/torque requirements. The experimental results for a six-phase case study compare the standard FCS-MPC with the suggested method, confirming that the VV-based MPC maintains the flux/torque regulation and successfully improves the power quality and efficiency.

Predictive Monitoring of Business Processes: A Survey

Abstract: Nowadays, process mining is becoming a growing area of interest in business process management (BPM). Process mining consists in the extraction of information from the event logs of a business process. From this information, we can discover process models, monitor and improve our processes. One of the applications of process mining, is the predictive monitoring of business process. The aim of these techniques is the prediction of quantifiable metrics of a running process instance with the generation of predictive models. The most representative approaches for the runtime prediction of business process are summarized in this paper. The different types of computational predictive methods, such as statistical techniques or machine learning approaches, and certain aspects as the type of predicted values and quality evaluation metrics, have been considered for the categorization of these methods. This paper also includes a summary of the basic concepts, as well as a global overview of the process predictive monitoring area, that can be used to support future efforts of researchers and practitioners in this research field.

Hydrogen Sulfide Signaling in Plants: Emerging Roles of Protein Persulfidation.

Abstract: Hydrogen sulfide (H2S) has been largely referred as a toxic gas and environmental hazard, but recent years, it has emerged as an important gas-signaling molecule with effects on multiple physiological processes in both animal and plant systems. The regulatory functions of H2S in plants are involved in important processes such as the modulation of defense responses, plant growth and development, and the regulation of senescence and maturation. The main signaling pathway involving sulfide has been proven to be through protein persulfidation (alternatively called S-sulfhydration), in which the thiol group of cysteine (-SH) in proteins is modified into a persulfide group (-SSH). This modification may cause functional changes in protein activities, structures, and subcellular localizations of the target proteins. New shotgun proteomic approaches and bioinformatic analyses have revealed that persulfidated cysteines regulate important biological processes, highlighting their importance in cell signaling, since about one in 20 proteins in Arabidopsis is persulfidated. During oxidative stress, an increased persulfidation has been reported and speculated that persulfidation is the protective mechanism for protein oxidative damage. Nevertheless, cysteine residues are also oxidized to different post-translational modifications such S-nitrosylation or S-sulfenylation, which seems to be interconvertible. Thus, it must imply a tight cysteine redox regulation essential for cell survival. This review is aimed to focus on the current knowledge of protein persulfidation and addresses the regulation mechanisms that are disclosed based on the knowledge from other cysteine modifications.

The AEROARMS Project: Aerial Robots with Advanced Manipulation Capabilities for Inspection and Maintenance

Abstract: This article summarizes new aerial robotic manipulation technologies and methods-aerial robotic manipulators with dual arms and multidirectional thrusters-developed in the AEROARMS project for outdoor industrial inspection and maintenance (IaM).

Chemical CO2 recycling via dry and bi reforming of methane using Ni-Sn/Al2O3 and Ni-Sn/CeO2-Al2O3 catalysts

Abstract: Carbon formation and sintering remain the main culprits regarding catalyst deactivation in the dry and bi-reforming of methane reactions (DRM and BRM, respectively). Nickel based catalysts (10 wt.%) supported on alumina (Al2O3) have shown no exception in this study, but can be improved by the addition of tin and ceria. The effect of two different Sn loadings on this base have been examined for the DRM reaction over 20 h, before selecting the most appropriate Sn/Ni ratio and promoting the alumina base with 20 wt.% of CeO2. This catalyst then underwent activity measurements over a range of temperatures and space velocities, before undergoing experimentation in BRM. It not only showed good levels of conversions for DRM, but exhibited stable conversions towards BRM, reaching an equilibrium H2/CO product ratio in the process. In fact, this work reveals how multicomponent Ni catalysts can be effectively utilised to produce flexible syngas streams from CO2/CH4 mixtures as an efficient route for CO2 utilisation.

Megahertz serial crystallography

Abstract: The new European X-ray Free-Electron Laser is the first X-ray free-electron laser capable of delivering X-ray pulses with a megahertz inter-pulse spacing, more than four orders of magnitude higher than previously possible. However, to date, it has been unclear whether it would indeed be possible to measure high-quality diffraction data at megahertz pulse repetition rates. Here, we show that high-quality structures can indeed be obtained using currently available operating conditions at the European XFEL. We present two complete data sets, one from the well-known model system lysozyme and the other from a so far unknown complex of a β-lactamase from K. pneumoniae involved in antibiotic resistance. This result opens up megahertz serial femtosecond crystallography (SFX) as a tool for reliable structure determination, substrate screening and the efficient measurement of the evolution and dynamics of molecular structures using megahertz repetition rate pulses available at this new class of X-ray laser source.

The mathematics teacher’s specialised knowledge (MTSK) model*

Abstract: The Spanish Government (EDU2013-44047-P and EDU2016-81994-REDT), the Mexican Sub-secretary of Higher Education (PRODEP), and the Research Centre COIDESO (University of Huelva, Spain) supported this research; Ministry of Economy and Competitiveness; Ministry of Economy Industry and Competitiveness.

Microglia in Alzheimer's Disease: Activated, Dysfunctional or Degenerative.

Abstract: Microglial activation has been considered a crucial player in the pathological process of multiple human neurodegenerative diseases. In some of these pathologies, such as Amyotrophic Lateral Sclerosis or Multiple Sclerosis, the immune system and microglial cells (as part of the cerebral immunity) play a central role. In other degenerative processes, such Alzheimer´s disease (AD), the role of microglia is far to be elucidated. In this “mini-review” we briefly highlight our recent data comparing the microglial response between amyloidogenic transgenic models, such as APP/PS1, and AD patients. Since the AD pathology could display regional heterogeneity, we focus our work at the hippocampal formation. In APP based models a prominent microglial response is triggered around A plaques. These strongly activated microglial cells could drive the AD pathology and, in consequence, could be implicated in the neurodegenerative process observed in models. On the contrary, the microglial response in human samples is, at least, partial or attenuated. This patent difference could simple reflect the lower and probably slower A production observed in human hippocampal samples, in comparison with models, or could reflect the consequence of a chronic long-standing microglial activation. Beside this differential response, we also observed microglial degeneration in Braak V-VI individuals that, indeed, could compromise their normal role of surveying the brain environment and respond to the damage. This microglial degeneration, particularly relevant at the dentate gyrus, might be mediated by the accumulation of toxic soluble phospho-tau species. The consequences of this probably deficient immunological protection, observed in AD patients, are unknown.