«φύσις [...] κρύπτεσθαιφιλεῖ» (DK22 B123). An approach from Hegel to a fragment of Heraclitus

Este trabajo elabora una aproximación a un significativo fragmento de Heráclito a partir del pensamiento de Hegel, apuntando también algunas problemáticas que se derivan de tal aproximación, particularmente en lo que refiere a la articulación entre naturaleza y pensamiento. Se tiene en cuenta para ello la perspectiva última de una filosofía, como la hegeliana, que pretende contener los principios de todas las filosofías precedentes, así como el principio subyacente, según Hegel, a la propia filosofía de Heráclito, que sería el devenir (Werden).This article develops an approach to a significant fragment of Heraclitus from Hegel's thought, also pointing out some questions that derive from such an approach, particularly regarding the articulation between nature and thought. For this, the ultimate perspective of a philosophy, such as the Hegelian, which aims to contain the principles of all the preceding philosophies is taken into account, as well as the underlying principle, according to Hegel, to Heraclitus´ own philosophy, which would the notion of becoming (Werden).info:eu-repo/semantics/publishedVersio

«φύσις [...] κρύπτεσθαι φιλεῖ» (DK22 B123). Aproximación desde Hegel a un fragmento de Heráclito

This article develops an approach to a significant fragment of Heraclitus from Hegel´s thought, also pointing out some questions that derive from such an approach, particularly regarding the articulation between nature and thought. For this, the ultimate perspective of a philosophy, such as the Hegelian, which aims to contain the principles of all the preceding philosophies is taken into account, as well as the underlying principle, according to Hegel, to Heraclitus´ own philosophy, which would the notion of becoming (Werden).Este trabajo elabora una aproximación a un significativo fragmento de Heráclito a partir del pensamiento de Hegel, apuntando también algunas problemáticas que se derivan de tal aproximación, particularmente en lo que refiere a la articulación entre naturaleza y pensamiento. Se tiene en cuenta para ello la perspectiva última de una filosofía, como la hegeliana, que pretende contener los principios de todas las filosofías precedentes, así como el principio subyacente, según Hegel, a la propia filosofía de Heráclito, que sería el devenir (Werden)

Determinación del grado de pronación mediante la utilización del sensor RunScribe Plus en población infantil que practica atletismo

[Resumen] El término running, que denota correr o carrera a pie, ha demostrado ser una de las actividades deportivas más practicadas (un 30,4% de los españoles practicaba este deporte en 2015). Este popular deporte está vinculado a factores de riesgo que pueden provocar una lesión, siendo la hiperpronación el principal factor de riesgo biomecánico asociado. Con el fin de poder determinar si esta hiperpronación está asociada a los riesgos de lesión, existen numerosas pruebas para medirla, el RunScribe Plus, es un nuevo dispositivo que se puede introducir directamente en el calzado y cuyo objetivo es medir la biomecánica de la marcha. Hay que destacar que, hasta ahora, el conocimiento que se había aportado sobre los tiempos máximos de pronación en la biomecánica de carrera, no se habían registrado con un dispositivo de estas características. Por lo tanto, el presente estudio pretende comprobar si este dispositivo aporta nuevos datos sobre los valores de los tiempos máximos de pronación de la carrera o si por el contrario existe una consistencia con los datos obtenidos con otros dispositivos. Objetivos: El propósito de este proyecto es determinar los valores de pronación durante la carrera con el sensor RunScribe Plus en niños y niñas entre 10 y 15 años que practican atletismo. La hipótesis principal de este proyecto es que los corredores de fondo con valores altos de pronación tienen mayor riesgo de padecer lesiones recurrentes en el pie asociadas a la práctica de la carrera de fondo. Metodología: Se realizará un estudio observacional transversal de prevalencia con diseño de metodología cuantitativa en niños y niñas entre 10 y 15 años que practican atletismo en la modalidad de carrera. La principal medición que se va a realizar es la medición del recorrido de pronación que se realizará con el aparato RunScribe Plus. El ámbito de estudio será el Club de Atletismo Narón en la provincia de A Coruña. Se partirá de una cifra de población desconocida. Para un nivel de confianza del 95 %, una precisión de 2o y una varianza de 28, ajustando el tamaño a un 15% de pérdidas, el tamaño muestral necesario es de 32 participantes.[Resumo] Introdución: O termino running, que denota correr ou carreira a pé, demostrou ser unha das actividades deportivas máis practicadas (un 30,4% dos españois practicaba este deporte en 2015). Este popular deporte está vinculado a factores de risco que poden provocar unha lesión, sendo a hiperpronación o principal factor de risco biomecánico asociado. Co fin de poder determinar se esta hiperpronación está asociada aos riscos de lesión, existen numerosas probas para medila, o RunScribe Plus, é un novo dispositivo que pódese introducir directamente no calzado e cuxo obxectivo é medir a biomecánica da marcha. Hai que destacar que, ata o de agora, o coñecemento que fora aportado sobre os tempos máximos de pronación da biomecánica de carreira, non se habían rexistrado con un dispositivo de estas características. Polo tanto, o presente estudo pretende comprobar se este dispositivo nos aporta novos datos sobre os valores dos tempos máximos de pronación da carreira ou se polo contrario existe unha consistencia cos datos obtidos con outros dispositivos. Obxectivos: O propósito de este proxecto é determinar os valores de pronación durante a carreira co sensor RunScribe Plus en nenos e nenas entre 10 e 15 anos que practican atletismo. A hipótese principal deste proxecto e que os corredores de fondo con valores altos de pronación teñen maior risco de padecer lesións recorrentes no pé asociados á práctica da carreira de fondo. Metodoloxía: Realizarase un estudio observacional transversal de prevalencia con deseño de metodoloxía cuantitativa en nenos e nenas entre 10 e 15 años que practican atletismo na modalidade de carreira. A principal medición que se vai realizar é a medición do recorrido de pronación que se realizará co aparato RunScribe Plus. O ámbito de estudo será o Clube de Atletismo Narón na provincia de A Coruña. Partirase dunha cifra de poboación descoñecida. Para un nivel de confianza do 95 %, una precisión de 2o y una varianza de 28, axustando o tamaño a un 15% de pérdidas, o tamaño muestral necesario é de 32 participantes.[Abstract] Introduction: The term running, which denotes running or running on foot, has proved to be one of the most widely practiced sports activities (30.4% of Spaniards practiced this sport in 2015). This popular sport is linked to risk factors that can cause an injury, with hyperpronation being the main associated biomechanical risk factor. In order to determine whether this hyperpronation is associated with the risk of injury, there are numerous tests to measure it. RunScribe Plus is a new device that can be inserted directly into the footwear and whose objective is to measure the biomechanics of walking. It should be noted that, until now, knowledge of maximum pronation times in running biomechanics has not been recorded with such a device. Therefore, the present study aims to verify whether this device provides new data on the values of maximum pronation times of the race or if, on the contrary, there is consistency with the data obtained with other devices. Objectives: The purpose of this project is to determine the pronation values during running with the RunScribe Plus sensor in children between 10 and 15 years of age who practice athletics. The main hypothesis of this project is that long-distance runners with high pronation values are at greater risk of recurrent foot injuries associated with long-distance running. Methodology: A transversal observational study of prevalence will be carried out with a design of quantitative methodology in boys and girls between 10 and 15 years old who practice athletics in the career modality. The main measurement to be carried out is the pronation path measurement to be performed with the RunScribe Plus. The field of study will be the Narón Athletics Club in the province of A Coruña. It will be based on an unknown population figure. For a confidence level of 95 %, an accuracy of 2o and a variance of 28, adjusting the size to a 15% loss, the necessary sample size is 32 participants.Traballo fin de grao (UDC.FEP). Podoloxía. Curso 2019/202

Control of planktonic bacterial cells and biofilms through magnetic hyperthermia

Disinfection of surfaces is a challenging task aggravated by bacteria's capacity to form biofilms, which enables them to survive and resist a wide variety of antimicrobial agents and hostile conditions. Potential application of magnetic hyperthermia (MH) as a new disinfection method against biofilms has been recently proposed however, studies comparing its performance and effectiveness on planktonic and biofilm cells from the same bacterial species remain unexplored. This work evaluated the effect of MH generated by iron oxide magnetic nanoparticles (MNP) against planktonic and biofilm cells Pseudomonas fluorescens, a major food spoilage microorganism. A P. fluorescens collection strain (ATCC 27663) was used and its biofilms allowed to form on silicone coupons during three days incubation in tryptic soy broth culture medium, at room temperature (20 ± 2ºC) and constant agitation of 120 rpm. Hyperthermia experiments were performed by applying an oscillating magnetic field of 873kHz and 100 Oe to several identical solutions of bacteria and MNP. To study cell viability as a function of temperature, magnetic heatings were performed at the same heating rate and up to different maximum temperatures. Bacterial survival was assessed through colony forming units count, while confocal laser scanning microscopy (CLS) was used to evaluate cellular membrane integrity of both bacterial life forms, as well as eventual effects of MH in biofilms' structure. Results showed a significant reduction (3 log) of viable planktonic cells when a maximum temperature of 40QC was reached, corresponding to only about 3 minutes of exposure to alternate magnetic field. A complete cellular eradication was achieved after only 8 minutes, when the maximum temperature was increased up to 55ºC. ln contrast, a significantly lower reduction of cellular viability was accomplished for biofilm s at the same temperatures, and no eradication was achieved even after 17 minutes of magnetic field exposure, reaching a maximum temperature of 60ºC. CLS images showed that MH inflicted cellular membrane damages both in planktonic and biofilm s cells, and also suggested that the outer cell layers of biofilms were more damaged than inner ones, as denoted by the higher amount of injured cells observed in the external layers. Summarizing, this work confirms the potential of MH as a disinfection method and shows for the first time its efficacy against a food spoilage microorganism. More importantly, it presents the first insights about how different bacterial life forms are affected by MH, showing a significantly different effectiveness against planktonic cells and biofilms

Control of bacterial cells growths by magnetic hyperthermia

In this work, we report the effectiveness of magnetic hyperthermia as a potential disinfection method against food spoilage microorganisms. High structural-magnetic quality magnetite nanoparticles have been found to be effective against bacterial microorganisms in solution under an oscillating magnetic field. Samples containing both magnetite nanoparticles and Pseudomonas fluorescens cells in aqueous solution have been subjected to an alternating magnetic field of chosen amplitude 100 Oe with frequency of 873 kHz for different times, achieving different maximum temperatures ranging from 35°C to 55°C. The subsequent colony forming units count evidenced an important decreasing of the cell survival with temperature in comparison to a conventional direct heating, ending in the total eradication of the microorganisms in relatively short times (~8 min). This ability of magnetic hyperthermia to control bacteria cells constitutes a novel contribution to the finding of new useful applications of hyperthermia different from biomedicine.This work was supported in part by the European Community’s under the FP7-Cooperation Programme through the MAGISTER project “Magnetic Scaffolds for in vivo Tissue Engineering” Large Collaborative Project FP7 and from European Regional Development Fund (ERDF) under the Northern Regional Operational Programme ON.2-O Novo Norte- for the acquisition of the main equipment used in this research. D. R. also acknowledges the financial support of Portuguese Foundation for Science and Technology (FCT) through the grant SFRH/BPD/72632/2010

Effect of magnetic hyperthermia on the structure of biofilm and cellular viability of a food spoilage bacterium

This work evaluated the effect of magnetic hyperthermia (MH) on planktonic cells and biofilms of a major food spoilage bacterium Pseudomonas fluorescens and its performance compared to a conventional direct heating (DH) technique. The results showed that MH had a greater and faster bactericidal effect, promoting a significant reduction in cell viability (≥3 Log CFU) in planktonic and biofilm cells, and leading to a complete eradication of planktonic cells at 55 °C (after only ~8 min). Accordingly, when comparing the same final temperatures, MH was more harmful to the integrity of cell membranes than DH, as observed in confocal laser scanning microscope images. Additionally, scanning electron microscope images revealed that exposure to MH had promoted modifications of the bacterial cell surface as well as of the structure of the biofilm. These results present the possibility of using MH out of the biomedical field as a potential disinfection method in food-related environments.This work was partly supported by the European Regional Development Fund (ERDF) under the Northern Regional Operational Programme ON.2-O Novo Norte- for the acquisition of the main equipment used in this research. DR also acknowledges the financial support of the Portuguese Foundation for Science and Technology (FCT) through [grant SFRH/BPD/72632/2010]. The authors are very grateful to Dr Edith Ariza and Dr Claudia Mota for their technical assistance in the SEM studies

Biocompatibility and bioimaging potential of fruit-based carbon dots

Photo-luminescent carbon dots (CD) have become promising nanomaterials and their synthesis from natural products has attracted attention by the possibility of making the most of affordable, sustainable and, readily-available carbon sources. Here, we report on the synthesis, characterization and bioimaging potential of CDs produced from diverse extensively produced fruits: kiwi, avocado and pear. The in vitro cytotoxicity and anticancer potential of those CDs were assessed by comparing human epithelial cells from normal adult kidney and colorectal adenocarcinoma cells. In vivo toxicity was evaluated using zebrafish embryos given their peculiar embryogenesis, with transparent embryos developing ex-utero, allowing a real-time analysis. In vitro and in vivo experiments revealed that the synthesized CD presented toxicity only at concentrations of ≥1.5 mg mL−1. Kiwi CD exhibited the highest toxicity to both cells lines and zebrafish embryos, presenting lower LD50 values. Interestingly, despite inducing lower cytotoxicity in normal cells than the other CDs, black pepper CDs resulted in higher toxicity in vivo. The bio-distribution of CD in zebrafish embryos upon uptake was investigated using fluorescence microscopy. We observed a higher accumulation of CD in the eye and yolk sac, avocado CD being the ones more retained, indicating their potential usefulness in bio-imaging applications. This study shows the action of fruit-based CDs from kiwi, avocado and pear. However the compounds present in these fruit-based CDs and their mechanism of action as a bioimaging agent need to be further explored.N. Vasimalai and Marisa P Sárria acknowledge the financial support from the Marie Curie COFUND Programme (NanoTRAINforGrowth). I. Pinheiro acknowledges the financial support from NanoDesk project (SOE1/P1/E0215) co-financed by the Interreg SUDOE Programme through the European Regional Development Fund (ERDF).info:eu-repo/semantics/publishedVersio

A carboxyl-functionalized covalent organic polymer for the efficient adsorption of saxitoxin

Saxitoxin (STX), the most widely distributed neurotoxin in marine waters and emerging cyanotoxin of concern in freshwaters, causes paralytic shellfish poisoning in humans upon consumption of contaminated shellfish. To allow for the efficient monitoring of this biotoxin, it is of high importance to find high-affinity materials for its adsorption. Herein, we report the design and synthesis of a covalent organic polymer for the efficient adsorption of STX. Two β-keto-enamine-based materials were prepared by self-assembly of 2,4,6-triformylphloroglucinol (Tp) with 2,5-diaminobenzoic acid (Pa-COOH) to give TpPa-COOH and with 2,5-diaminotoluene (Pa-CH3) to give TpPa-CH3. The carboxylic acid functionalized TpPa-COOH outperformed the methyl-bearing counterpart TpPa-CH3 by an order of magnitude despite the higher long-range order and surface area of the latter. The adsorption of STX by TpPa-COOH was fast with equilibrium reached within 1 h, and the Langmuir adsorption model gave a calculated maximum adsorption capacity, Qm, of 5.69 mg g-1, making this material the best reported adsorbent for this toxin. More importantly, the prepared TpPa-COOH also showed good reusability and high recovery rates for STX in natural freshwater, thereby highlighting the material as a good candidate for the extraction and pre-concentration of STX from aquatic environments.publishe