On the exponent of convergence of negatively curved manifolds without Green's function

In this paper we prove that for every complete n-dimensional Riemannian manifold without Green's function and with its sectional curvatures satisfying K ≤−1, the exponent of convergence is greater than or equal to n − 1. Furthermore, we show that this inequality is sharp. This result is well known for manifolds with constant sectional curvatures K = −1

Vascular lysyl oxidase over-expression alters extracellular matrix structure and induces oxidative stress

Lysyl oxidase (LOX) participates in the assembly of collagen and elastin fibres. The impact of vascular LOX over-expression on extracellular matrix (ECM) structure and its contribution to oxidative stress has been analysed. Methods Studies were conducted on mice over-expressing LOX (Tg), specifically in smooth muscle cells (VSMC). Gene expression was assessed by real-time PCR analysis. Sirius Red staining, H 2 O 2 production and NADPH oxidase activity were analysed in different vascular beds. The size and number of fenestra of the internal elastic lamina were determined by confocal microscopy. Results LOX activity was up-regulated in VSMC of transgenic mice compared with cells from control animals. At the same time, transgenic cells deposited more organised elastin fibres and their supernatants induced a stronger collagen assembly in in vitro assays. Vascular collagen cross-linking was also higher in Tg mice, which showed a decrease in the size of fenestrae and an enhanced expression of Fibulin-5. Interestingly, higher H 2 O 2 production and NADPH oxidase activity was detected in the vascular wall from transgenic mice. The H 2 O 2 scavenger catalase attenuated the stronger deposition of mature elastin fibres induced by LOX transgenesis. Conclusions LOX over-expression in VSMC was associated with a change in the structure of collagen and elastin fibres. LOX could constitute a novel source of oxidative stress that might participate in elastin changes and contribute to vascular remodellingLa lisil oxidasa (LOX) contribuye al ensamblaje de las fibras de colágeno y elastina de la matriz extracelular (MEC). Hemos determinado las consecuencias de la sobre-expresión vascular de LOX sobre la estructura de la MEC y su contribución al estrés oxidativo. Métodos: Los estudios se desarrollaron en ratones que sobre-expresan la LOX (Tg) específicamente en células musculares lisas vasculares (CMLV). Se realizaron análisis por PCR a tiempo real, tinción de rojo sirio, producción de H2O2 y actividad NADPH oxidasa. Se caracterizaron las fenestras de la lámina elástica interna mediante microscopía confocal. Resultados: Las CMLV de ratones transgénicos presentaron niveles de actividad LOX superiores a los de animales control. En consonancia, las células transgénicas depositaron más fibras de elastina organizada y sus sobrenadantes indujeron un mayor ensamblaje de colágeno en ensayos in vitro. El nivel de colágeno maduro fue superior en la pared vascular de ratones Tg, que presentaban un menor área de las fenestras y un aumento de la expresión de la Fibulina-5. La producción vascular de H2O2 y la actividad NADPH oxidasa fueron superiores en los ratones transgénicos. La incubación de CMLV con catalasa atenuó el incremento en la deposición de fibras de elastina madura inducido por la transgénesis de LOX. Conclusiones: La sobre-expresión de la LOX en CMLV se asocia a una alteración de la estructura vascular del colágeno y la elastina. La LOX podría constituir una nueva fuente de estrés oxidativo que participaría en la alteración estructural de la MEC y podría contribuir al remodelado vascularEste estudio se ha financiado por la Fundación Española de Aterosclerosis, Beca SEA/FEA de Investigación básica 2016 y por el Ministerio de Economía y Competitividad (MINECO)-Instituto de Salud Carlos III (ISCIII) [proyectos PI15/01016, PI13/01488, SAF2012-36400; SAF2015-64767-R]. El CIBER de Enfermedades Cardiovasculares es una iniciativa del ISCIII. AMB recibió una ayuda del programa Ramón y Cajal (RYC-2010-06473). El estudio ha sido cofinanciado por el Fondo Europeo de Desarrollo Regional (FEDER

Interplay of Postprandial Triglyceride-Rich Lipoprotein Composition and Adipokines in Obese Adolescents

In the context of the alarming rise of infant obesity and its health implications, the present research aims to uncover disruptions in postprandial lipid metabolism and the composition of triglyceride-rich lipoproteins in obese adolescents. A double-blind, controlled clinical trial in the postprandial phase on 23 adolescents aged 12 to 16 years was carried out. Twelve participants were categorized as obese (BMI > 30 kg/m2 and percentile > 95) and 11 as normal-weight (BMI = 20–25 kg/m2, percentile 5–85). Blood samples were collected after a 12-h overnight fast and postprandially after consumption of a standardized breakfast containing olive oil, tomato, bread, orange juice, and skimmed milk. Obese adolescents exhibited elevated triglyceride concentrations in both fasting and postprandial states and higher TG/apo-B48 ratios, indicating larger postprandial triglyceride-rich lipoprotein (TRL) particle size, which suggests impaired clearance. Obese subjects also exhibited higher n-6 PUFA concentrations, potentially linked to increased TRL hydrolysis and the release of pro-inflammatory adipokines. In contrast, TRL from normal-weight individuals showed higher concentrations of oleic acid and DHA (n-3 PUFA), with possible anti-inflammatory effects. The results indicate an interplay involving postprandial TRL metabolism and adipokines within the context of adolescent obesity, pointing to potential cardiovascular implications in the future.Spanish Ministry of Economy and Competitiveness (Grant number AGL2011-23810)”“Next Generation EU” fundsEuropean Union Recovery, Transformation and Resilience PlanMinistry of Universities, in the framework of the Margarita Salas, Maria Zambrano grants for the Requalification of the Spanish University System 2021–2023, organized by the Pablo de Olavide University, Sevill

Biotinylated Cell-penetrating Peptides to Study Intracellular Protein-protein Interactions

[EN] Here we present a protocol to study intracellular protein-protein interactions that is based on the widely used biotin-avidin pull-down system. The modification presented includes the combination of this technique with cell-penetrating sequences. We propose to design cell-penetrating baits that can be incubated with living cells instead of cell lysates and therefore the interactions found will reflect those that occur within the intracellular context. Connexin43 (Cx43), a protein that forms gap junction channels and hemichannels is down-regulated in high-grade gliomas. The Cx43 region comprising amino acids 266-283 is responsible for the inhibition of the oncogenic activity of c-Src in glioma cells. Here we use TAT as the cell-penetrating sequence, biotin as the pull-down tag and the region of Cx43 comprised between amino acids 266-283 as the target to find intracellular interactions in the hard-to-transfect human glioma stem cells. One of the limitations of the proposed method is that the molecule used as bait could fail to fold properly and, consequently, the interactions found could not be associated with the effect. However, this method can be especially interesting for the interactions involved in signal transduction pathways because they are usually carried out by intrinsically disordered regions and, therefore, they do not require an ordered folding. In addition, one of the advantages of the proposed method is that the relevance of each residue on the interaction can be easily studied. This is a modular system; therefore, other cell-penetrating sequences, other tags, and other intracellular targets can be employed. Finally, the scope of this protocol is far beyond protein-protein interaction because this system can be applied to other bioactive cargoes such as RNA sequences, nanoparticles, viruses or any molecule that can be transduced with cell-penetrating sequences and fused to pull-down tags to study their intracellular mechanism of action

Towards a fuzzy-based multi-classifier selection module for activity recognition applications

Performing activity recognition using the information provided by the different sensors embedded in a smartphone face limitations due to the capabilities of those devices when the computations are carried out in the terminal. In this work a fuzzy inference module is implemented in order to decide which classifier is the most appropriate to be used at a specific moment regarding the application requirements and the device context characterized by its battery level, available memory and CPU load. The set of classifiers that is considered is composed of Decision Tables and Trees that have been trained using different number of sensors and features. In addition, some classifiers perform activity recognition regardless of the on-body device position and others rely on the previous recognition of that position to use a classifier that is trained with measurements gathered with the mobile placed on that specific position. The modules implemented show that an evaluation of the classifiers allows sorting them so the fuzzy inference module can choose periodically the one that best suits the device context and application requirements

Insights on the removal of the azole pesticides included in the EU Watch List by Catalytic Wet Peroxide Oxidation

The aim of this work is to evaluate the feasibility of the Catalytic Wet Peroxide Oxidation (CWPO) process using the inexpensive and environmentally friendly Fe3O4-R400 catalyst for the removal from water of a representative group of azole pesticides recently listed in the European Union (EU) Watch Lists (penconazole (PEN), prochloraz (PCZ), tebuconazole (TEB), tetraconazole (TET), metconazole (MET)). The complete removal of these pollutants (1000 μg L−1) was achieved in <1 h reaction time under ambient conditions using a catalyst concentration of 0.5 g L−1 and the stoichiometric dose of H2O2 (3 – 5 mg L−1) at a slightly acidic pH (pH0 = 5.0). To further demonstrate the effectiveness of the process, the ecotoxicity abatement was also considered. The initial toxicity of the pesticides and the CWPO effluents were evaluated with the brine shrimp Artemia salina and the bacterium Vibrio fischeri. Remarkably, the effluents were non-toxic for V. fischeri and a decrease of more than 80% in mortality was achieved for A. salina. Furthermore, the versatility of the system was proved in real water matrices (surface water and WWTP effluent), although a slight decrease on the oxidation rate was found due to the occurrence of organic matter and inorganic salts. The reactivity of the azole pesticides was finally compared with the achieved for other groups of pollutants included in the EU Watch Lists (pharmaceuticals, hormones, and neonicotinoid pesticides). Clearly, azole compounds showed the least reactivity to oxidation, suggesting that they can be used as general indicators of the overall efficiency of the proposed catalytic system for the removal of EU Watch Lists micropollutantsThis research has been supported by the Spanish AEI through the project PID2019-105079RB-100 and by the CM, Spain through the project P2018/EMT-4341. M. Munoz, N. Lopez-Arago and J. Nieto-Sandoval thanks the Spanish AEI for the Ramón y Cajal postdoctoral contract (RYC-2016-20648), the FPI predoctoral, Spain grant (PRE2020-09452) and the FPI postdoctoral, Spain grant (BES-2017-081346), respectivel

Dynamic Analysis, Stability and Design of Grid Forming Converters With PI-Based Voltage Control in DC and 3-Phase AC Microgrids

This paper analyzes the dynamic behavior of the voltage control loop based on proportional-integral regulators, commonly used for grid-forming converters in 3-phase AC and DC Microgrids and applications that involve a DC-link voltage control. The paper proposes a simple and accurate generalized analysis useful both for the system characterization and design. Two different control schemes, based on linear (Direct Voltage Control, DVC) and quadratic voltage feedback (Quadratic Voltage Control, QVC), are analytically studied, simulated and experimentally tested, demonstrating a superior performance of the QVC under the presence of constant power loads. The operation limits, the system stability and the disturbance rejection capability are analyzed considering the effect of control and plant parameters and the effect of the different types of disturbances and the operating point, taking into account the non-linearities of the system. The analysis is mainly focused on the effect of constant power loads given their negative impact on the system performance. The study provides a generic procedure for the analysis and design of proportional-integral voltage controllers, including the selection of the system capacitance for meeting specific dynamic specifications while considering system characteristics as the load level, the stability margins and the maximum voltage deviation under disturbances

Application of catalytic hydrodechlorination for the fast removal of chlorinated azole pesticides in drinking water

Catalytic hydrodechlorination (HDC) is regarded as a promising purifying technology for drinking water treatment. So far, it has proved to be highly effective for the removal of different groups of chlorinated micropollutants including pharmaceuticals, neonicotinoid pesticides, personal care products or chloroacetic acids. The azole pesticides, recently included in the EU Watch Lists (Decisions 2020/1161 and 2022/1307), are a group of micropollutants of particular concern for drinking water given their high toxicity, persistence, and bioaccumulation potential. In this work, the feasibility of HDC for the removal of a representative group of chlorinated azole pesticides tebuconazole (TEB), tetraconazole (TET), prochloraz (PCZ), penconazole (PEN), metconazole (MET) and imazalil (IMZ)) is demonstrated, and their reactivity is compared with that observed for other halogenated micropollutant groups. Notably, all the pesticides investigated in this work (100 μg L− 1 ) were completely dechlorinated within 30 min under ambient conditions using a 1 wt% Pd/Al2O3 catalyst concentration of 0.25 g L− 1 and a H2 feeding of 50 mL N min− 1 . The experimental data were accurately described by a pseudo-first order kinetic equation and rate constant values in the range from 1.08 to 2.60 L gcat − 1 min− 1 were obtained. These values are quite close to those achieved for the most reactive neonicotinoid pesticides and significantly higher than the obtained for chloroacetic acids and most pharmaceuticals (e.g. diclofenac, sertraline or chlorpromazine). From the identification of the generated reaction intermediates and the final nonchlorinated products, sequential reaction pathways were proposed for each pollutant. Remarkably, despite the high toxicity exhibited by the azole pesticides tested, with LC50 values within the 0.4–7.0 mg L− 1 range using A. salina, HDC effluents were non-toxic in all cases. Furthermore, the catalyst showed a remarkable stability upon three consecutive runs. Finally, the versatility of the process was demonstrated in the treatment of real aqueous matrices such as DWTP and tap water, where no significant differences were found either in terms of activity or stabilityThis research has been supported by the Spanish MINECO through project PID2019-105079RB-I00 and by the CM through project P2018/ EMT-4341. J. Nieto-Sandoval and M. Munoz thanks the MINECO for the FPI contract (BES-2017-081346) and the Ramon ´ y Cajal postdoctoral contract (RYC-2016-20648), respectively. R. B. del Olmo thanks the Operational Program for Youth Employment and the Youth Employment Initiative (YEI) of the CM for his contract as Research Assistant (PEJ2020-AI/AMB-19161

Influence of soil pH in the effects of ZnONPs on the antioxidant activities and Zn uptake in three plant species (T aestivum, R. sativus and Z. mays)

In recent years, the study of phytotoxicity of NPs has made rapid progress, but important issues remain to be solved, among them, the role of soil and the importance of the physicochemical soil characteristics for their toxicity and accumulation potential

Mobile just-in-time training application for emergency healthcare

While the applications of just-in-time training are more and more spread, the ubiquitous mobile technology has not found practical uses of this training strategy. As an original example of services for healthcare, we present in this work an application of eTraining that makes use of mobile telephones to transmit medical and on-site information content to emergency medical personnel that attend and emergency. The state-of-the-art in related technologies, overall architecture, and functioning of JITTER (for Just-In-Time Training for Emergency Responders) is described in this work.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech