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The COVID–19 pandemic led to local oxygen shortages worldwide. To gain a better understanding of oxygen consumption with different respiratory supportive therapies, we conducted an international multicenter observational study to determine the precise amount of oxygen consumption with high-flow nasal oxygen (HFNO) and with mechanical ventilation. A retrospective observational study was conducted in three intensive care units (ICUs) in the Netherlands and Spain. Patients were classified as HFNO patients or ventilated patients, according to the mode of oxygen supplementation with which a patient started. The primary endpoint was actual oxygen consumption; secondary endpoints were hourly and total oxygen consumption during the first two full calendar days. Of 275 patients, 147 started with HFNO and 128 with mechanical ventilation. Actual oxygen use was 4.9-fold higher in patients who started with HFNO than in patients who started with ventilation (median 14.2 [8.4–18.4] versus 2.9 [1.8–4.1] L/minute; mean difference = 11.3 [95% CI 11.0–11.6] L/minute; P < 0.01). Hourly and total oxygen consumption were 4.8-fold (P < 0.01) and 4.8-fold (P < 0.01) higher. Actual oxygen consumption, hourly oxygen consumption, and total oxygen consumption are substantially higher in patients that start with HFNO compared with patients that start with mechanical ventilation. This information may help hospitals and ICUs predicting oxygen needs during high-demand periods and could guide decisions regarding the source of distribution of medical oxygen.

Mechanical ventilation is the most extensively employed life support intervention among patients with severe respiratory fail ure of different etiologies. In this context, consistent delivery of the most suitable tidal volume (VT) to the patientis criticalto achieving personalized mechanical ventilation. Indeed, in addition to its con tribution to minute volume for optimization of blood gas exchange,appropriate VT strategies are critical to avoid ventilator-induced lung injury in the general context of lung-protective ventilation and when specifically applying ultra-low tidal volume ventilation. Additionally, VT is required to compute respiratory system com pliance or ventilatory ratio, useful indices in the classification of patient phenotype and estimation of prognosis.

[ES] El objetivo de este trabajo radica en la propuesta de realizar un viaje tripulado para una posterior colonización del planeta Marte. En primer lugar, se abordará toda la normativa y legislación a cumplir para una empresa de dichas características. Aunque aún no se haya realizado una campaña semejante (en Marte), la mayoría de los obstáculos ya han aparecido anteriormente, con viajes tripulados a la Luna o al espacio exterior. Se dividirá el proyecto en cuatro bloques principales. El primero recogerá las misiones espaciales a Marte más relevantes hasta la fecha. En el segundo se explicará la legislación existente sobre Marte y las carencias de ésta. El tercero tratará de justificar y posibilitar el viaje en sí, abarcando la planificación des de la Tierra, tratados y legislación a cumplir, así como la ética. El último bloque se centrará en la implementación de la colonia en Marte. Se recogerán en este escrito las posibilidades para una vivienda a medio-largo plazo autosuficiente, sostenible y con futuro. Se tratará siempre de enfocar dicha colonización con realismo y viabilidad, aun siendo una empresa que hoy en día no se ha logrado. Por esta razón, se realizarán una serie de propuestas interesantes para salvar los obstáculos más importantes, [EN] The objective of this work lies in the proposal to carry out a manned trip for a subsequent colonization of the planet Mars. In the first place, all the regulations and legislation to be complied with for a company of these characteristics will be addressed. Although such a campaign has not yet been carried out (on Mars), most of the obstacles have already appeared before, with manned trips to the Moon or to outer space. The project will be divided into four main blocks. The first will collect the most relevant space missions to Mars to date. In the second, the existing legislation on Mars and its shortcomings will be explained. The third will try to justify and enable the trip itself, covering planning from Earth, treaties and legislation to comply with, as well as ethics. The last block will focus on the implementation of the colony on Mars. The possibilities for a self-sufficient, sustainable and futureoriented home in the medium-long term will be collected in this writing. It will always be a matter of approaching said colonization with realism and feasibility, even though it is an undertaking that has not been achieved today. For this reason, a series of interesting proposals will be made to overcome the most important obstacles, [CA] L'objectiu d'aquest treball rau en la proposta de realitzar un viatge tripulat per a una posterior colonització del planeta Mart. En primer lloc, s'abordarà tota la normativa i la legislació a complir per a una empresa d'aquestes característiques. Encara que encara no s'hagi fet una campanya semblant (a Mart), la majoria dels obstacles ja han aparegut anteriorment, amb viatges tripulats a la Lluna o a l'espai exterior. Es dividirà el projecte en quatre blocs principals. El primer recollirà les missions espacials a Mart més rellevants fins ara. En el segon, s'explicarà la legislació existent sobre Mart i les mancances d'aquesta. El tercer tractarà de justificar i possibilitar el viatge en si, abastant la planificació des de la Terra, tractats i legislació a complir així com l'ètica. El darrer bloc es centrarà en la implementació de la colònia a Mart. Es recolliran en aquest escrit les possibilitats per a un habitatge a mitjà-llarg termini autosuficient, sostenible i amb futur. Es tractarà sempre d'enfocar aquesta colonització amb realisme i viabilitat, tot i ser una empresa que avui dia no s'ha aconseguit. Per aquesta raó, es faran una sèrie de propostes interessants per salvar els obstacles més importants

DFT modelling of the oxygen reduction and evolution reactions (ORR and OER) habitually makes use of semiempirical corrections to oxygen in the gas phase. Although such corrections are tacit in the model, they should not be overlooked. In this article, we calculate the errors in the total energy of oxygen for commonly used exchange-correlation functionals, PW91, RPBE, PBE, and BEEF-vdW, to show that, for all functionals tested, the error is at least 0.3 eV. We discuss the impact this sizeable error in oxygen has on the modelling of the ORR and the OER. The error due to oxygen affects not only the overall equilibrium potential of the reaction, but also the energies of individual mechanistic steps. This illustrates that understanding the reasoning behind the semiempirical corrections for oxygen is important for researching new catalysts which may have different potential limiting steps.

Nowadays, reaction mechanisms of photo-Fenton process with chelated iron are not yet clearly defined. In this study, five organic fertilizers were used as iron complexes to investigate the role of sunlight and oxygen in photo-Fenton at near neutral pH. UV absorbance and stability constant of each selected iron chelate is different, and this work demonstrates that these parameters affect the reaction mechanisms in SMX degradation. Irradiation experiments without H2O2 revealed that only EDDS-Fe and DTPA-Fe achieved SMX degradation, but different iron release. These results, together with soluble oxygen free experiments, allowed the proposal of complementary reaction mechanisms to those of the classical photo-Fenton. The proposed mechanisms start through the potential photoexcitation of the iron complex, followed by subsequent oxygen-mediated hydroxyl radical generation reactions that are different for EDDS-Fe and DTPA-Fe. Moreover, irradiation experiments using EDTA-Fe and HEDTA-Fe had negligible SMX degradation despite iron release was observed, evidencing the differences between iron chelates., The authors are grateful with the Ministry of Economy and Competitiveness (project CTQ2017-86466-R, MINECO/FEDER, UE), AGAUR-Generalitat de Catalunya (project 2017SGR-131) and Nuria López FPU research fellowship (FPU-16/02101) financed by Ministry of Science, Innovation and Universities.

The naked mole rat (NMR), a long-lived and cancer-resistant rodent, is highly resistant to hypoxia. Here, using robust cellular models wherein the mouse telomeric protein TRF1 is substituted by NMR TRF1 or its mutant forms, we show that TRF1 supports maximal glycolytic capacity under low oxygen, shows increased nuclear localization and association with telomeres, and protects telomeres from replicative stress. We pinpoint this evolutionary gain of metabolic function to specific amino acid changes in the homodimerization domain of this protein. We further find that NMR TRF1 accelerates telomere shortening. These findings reveal an evolutionary strategy to adapt telomere biology for metabolic control under an extreme environment., SCOPUS: ar.j, info:eu-repo/semantics/published

Background One of the most prevalent causes of fetal hypoxia leading to stillbirth is placental insufficiency. Hemodynamic changes evaluated with Doppler ultrasound have been used as a surrogate marker of fetal hypoxia. However, Doppler evaluation cannot be performed continuously. As a first step, the present work aimed to evaluate the performance of miniaturized electrochemical sensors in the continuous monitoring of oxygen and pH changes in a model of acute hypoxia-acidosis. Methods pH and oxygen electrochemical sensors were evaluated in a ventilatory hypoxia rabbit model. The ventilator hypoxia protocol included 3 differential phases: basal (100% FiO2), the hypoxia-acidosis period (10% FiO2) and recovery (100% FiO2). Sensors were tested in blood tissue (ex vivo sensing) and in muscular tissue (in vivo sensing). pH electrochemical and oxygen sensors were evaluated on the day of insertion (short-term evaluation) and pH electrochemical sensors were also tested after 5 days of insertion (long-term evaluation). pH and oxygen sensing were registered throughout the ventilatory hypoxia protocol (basal, hypoxia-acidosis, and recovery) and were compared with blood gas metabolites results from carotid artery catheterization (obtained with the EPOC blood analyzer). Finally, histological assessment was performed on the sensor insertion site. One-way ANOVA was used for the analysis of the evolution of acid-based metabolites and electrochemical sensor signaling results; a t-test was used for pre- and post-calibration analyses; and chi-square analyses for categorical variables. Results At the short-term evaluation, both the pH and oxygen electrochemical sensors distinguished the basal and hypoxia-acidosis periods in both the in vivo and ex vivo sensing. However, only the ex vivo sensing detected the recovery period. In the long-term evaluation, the pH electrochemical sensor signal seemed to lose sensibility. Finally, histological assessment revealed no signs of alteration on the day of evaluation (short-term), whereas in the long-term evaluation a sub-acute inflammatory reaction adjacent to the implantation site was detected. Conclusions Miniaturized electrochemical sensors represent a new generation of tools for the continuous monitoring of hypoxia-acidosis, which is especially indicated in high-risk pregnancies. Further studies including more tissue-compatible material would be required in order to improve long-term electrochemical sensing.

[cat] Els treballs realitzats en aquesta tesi doctoral s’han dirigit cap al desenvolupament, optimització i regeneració dels sensors d’oxigen per a la detecció d’humitat en entorns d’alta temperatura per acomplir amb un objectiu concret: implementar un sensor d’oxigen planar basat en YSZ a l’interior d’un forn industrial per a la quantificació de la humitat present a l’interior de la cambra. L’assoliment d’aquest objectiu concret s’han aconseguit gràcies al desenvolupament dels diversos estudis que es presenten en aquesta tesi. En una primera part del treball més descriptiva s’emmarca la necessitat del desenvolupament (centrada en la detecció de la humitat en condicions d’alta temperatura) i es presenta la descripció dels processos de la fabricació dels sensors i d’obtenció dels materials mitjançant la tecnologia ceràmica multicapa d’alta temperatura. La robustesa dels mètodes de fabricació aplicats, han permès acotar diferents paràmetres de disseny dels sensors per garantir que tots els sensors fabricats es troben dins els intervals definits. Posteriorment la tesi es centra en la caracterització electroquímica dels sensors i dels seus processos de degradació i regeneració en les condicions de treball. S’ha aprofundit en l’estudi i coneixement de les propietats difusores dels sensors i s’ha determinat una geometria de la zona difusora que garanteix una resposta adequada dels sensors en diferents condicions de mesura. Per acomplir amb aquest objectiu, s’ha estudiat la resposta obtinguda per a diferents porositats dels canals difusors i s’ha determinat la geometria de la zona difusora per tal que ofereixi una lectura del corrent límit adequada en les atmosferes amb continguts d’oxigen més elevats. S’ha determinat la temperatura mínima operacional de T=750ºC per a garantir un corren límit adequat en aire quan els sensors presenten un corrent màxim de 6mA. A partir de l’anàlisi dels resultats en atmosferes humides, s’ha determinat la tensió de polarització màxima aplicable a la cel·la, quantificada en 0.5V, i la màxima temperatura de treball, quantificada en T=950ºC. Seguidament es presenta un estudi electroquímic dels sensors i dels seus efectes de degradació en entorns d’humitat. Aquest estudi es basa en la caracterització mitjançant espectroscòpia d’impedància (EIS) dels sensors complerts. S’han pogut diferenciar tres contribucions RC amb freqüències de transició clarament diferenciades. Les correlacions entre les respostes obtingudes, les condicions operacionals de temperatura i les atmosferes de mesura han permès assignar la transició observada a altes freqüències (ArcAF) amb els punts triples (TPB), la transició que apareix a freqüències intermitges (ArcFM) s’ha relacionat amb l’elèctrode exterior i la transició observada a baixes freqüències (ArcBF) s’ha associat amb l’elèctrode interior. Els estudis realitzats amb diferents configuracions dels sensors (cavitats difusores més grans o capes protectores més gruixudes) han permès avaluar el solapament de les diferents contribucions i justificar les diferents formes de les respostes obtingudes en les mesures realitzades a 2 elèctrodes (que poden presentar 2 o 3 transicions diferenciables). A partir d’aquests resultats, s’han pogut determinar els efectes de la degradació dels sensors, concentrats sobretot en la desactivació dels punt triples generada per l’adsorció de molècules d’H2O i a la formació d’òxids de platí. Finalment, en l’estudi de regeneració presentat s’ha pogut determinar el grau de reversibilitat de la degradació dels sensors i definir un cicle regeneratiu que permeti augmentar la durabilitat dels sensors en les atmosferes de treball. S’ha demostrat que la regeneració mitjançant l’aplicació d’un potencial catòdic és molt més efectiva i té uns efectes més perllongats en el temps. S’ha provat que la funcionalitat del sensor pot recuperar-se amb només una reactivació parcial dels punts triples., [eng] The work carried out in this doctoral thesis has been directed towards the development, optimization, and regeneration of oxygen sensors for the detection of humidity in high temperature environments to fulfill a specific goal: to implement a planar YSZ-based oxygen sensor inside an industrial furnace for quantifying the moisture present inside the chamber. A detailed study of the diffusive properties of the sensors has been undergone so that a geometry of the diffuser zone was determined to guarantee an adequate response of the sensors in the different measurement conditions. An electrochemical study of sensors in humid environments is presented. This study is based on the impedance spectroscopy (EIS) characterization of complete sensors. Three RC contributions have been characterized with clearly differentiated transition frequencies. The correlations between the obtained responses with different operating conditions of temperature and atmospheres, have allowed to assign the transition observed to high frequencies (ArcAF) with the triple phase boundaries (TPBs), the transition that appears to intermediate frequencies (ArcFM) has been related to the outer electrode and the observed transition to low frequencies (ArcBF) has been associated with the inner electrode. Studies carried out with different configurations of the sensors have allowed to evaluate the overlap of the different contributions and justify the different forms of the responses obtained in the measurements made at 2 electrodes. From these results, it has been possible to determine the effects of the degradation of the sensors, concentrated mainly on the deactivation of the TPBs generated by the adsorption of H2O molecules and the formation of platinum oxides. Finally, it has been possible to determine the degree of reversibility of the degradation of the sensors and to define a regenerative cycle. Regeneration by applying a cathodic potential has been shown to be much more effective and has longer-lasting effects.

Respirar està indissociablement lligat a la vida humana. Ho fem per primer cop quan naixem, i no deixem de fer-ho fins al darrer alè de la nostra vida. Respirem per poder agafar l'oxigen de l'aire. Tots sabem què és l'oxigen. És un dels elements de la Taula Periòdica, on ocupa la posició número 8, entre el nitrogen i el fluor. Poques substàncies reflecteixen tan bé la dualitat que determina la nostra existència. El consumim sense parar, com molts altres éssers vius, però lluny d'acabar-se els organismes fotosintètics, com les plantes, s'encarreguen de restituir-lo. Necessitem energia per viure, i la manera més eficient d'obtenir-la és a través de l'oxidació de determinades biomolècules a l'interior de les cèl·lules. És imprescindible, però al mateix temps és tòxic si en tenim massa, perquè és molt reactiu. Aquesta lluita entre contraris posa de manifest un dels paradigmes de la vida. Som un delicat equilibri condicionat per l'oxigen i l'energia.

The electrolysis of seawater, a significantly more abundant natural reservoir than freshwater, stands as a promising alternative for sustainable hydrogen production, provided that the competitive chloride electro-oxidation is minimized. Herein, we propose an original material combination to selectively trigger oxygen evolution from seawater at expenses of chlorine generation. The target systems, based on MnO2 or Mn2O3 decorated with Fe2O3 or Co3O4, are fabricated by plasma enhanced-chemical vapor deposition of manganese oxides, functionalization with Fe2O3 and Co3O4 by sputtering, and annealing in air/Ar to obtain Mn(IV)/Mn(III) oxides. Among the various options, MnO2 decorated with Co3O4 yields the best performances in alkaline seawater splitting, with an outstanding Tafel slope of approximate to 40 mV x dec(-1) and an overpotential of 450 mV, enabling to rule out chlorine evolution. These attractive performances, resulting from the synergistic contribution of catalytic and electronic effects, open the door to low-cost hydrogen generation from seawater under real-world conditions, paving the way to eventual large-scale applications.

Earth-abundant and eco-friendly manganese oxides are promising platforms for the oxygen evolution reaction (OER) in water electrolysis. Herein, a versatile and potentially scalable route to gold-decorated manganese oxide-based OER electrocatalysts is reported. In particular, MnxOy(MnO2, Mn2O3) host matrices are grown on conductive glasses by plasma assisted-chemical vapor deposition (PA-CVD), and subsequently functionalized with gold nanoparticles (guest) as OER activators by radio frequency (RF)-sputtering. The final selective obtainment of MnO2- or Mn2O3-based systems is then enabled by annealing under oxidizing or inert atmosphere, respectively. A detailed material characterization evidences the formation of high-purity Mn(x)O(y)dendritic nanostructures with an open morphology and an efficient guest dispersion into the host matrices. The tailoring of Mn(x)O(y)phase composition and host-guest interactions has a remarkable influence on OER activity yielding, for the best performing Au/Mn(2)O(3)system, a current density of approximate to 5 mA cm(-2)at 1.65 V versus the reversible hydrogen electrode (RHE) and an overpotential close to 300 mV at 1 mA cm(-2). Such results, comparing favorably with literature data on manganese oxide-based materials, highlight the importance of compositional control, as well as of surface and interface engineering, to develop low-cost and efficient anode nanocatalysts for water splitting applications.

The development of catalysts with high intrinsic activity towards the oxygen evolution reaction (OER) plays a critical role in sustainable energy conversion and storage. Herein, we report on the development of efficient (photo)electrocatalysts based on functionalized MnO2 systems. Specifically, β-MnO2 nanostructures grown by plasma enhanced-chemical vapor deposition on fluorine-doped tin oxide (FTO) or Ni foams were decorated with Co3O4 or Fe2O3 nanoparticles by radio frequency sputtering. Upon functionalization, FTO-supported materials yielded a performance increase with respect to bare MnO2, with current densities at 1.65 V vs. the reversible hydrogen electrode (RHE) up to 3.0 and 3.5 mA/cm2 in the dark and under simulated sunlight, respectively. On the other hand, the use of highly porous and conductive Ni foam substrates enabled to maximize cooperative interfacial effects between catalyst components. The best performing Fe2O3/MnO2 system provided a current density of 17.9 mA/cm2 at 1.65 V vs. RHE, an overpotential as low as 390 mV, and a Tafel slope of 69 mV/decade under dark conditions, comparing favorably with IrO2 and RuO2 benchmarks. Overall, the control of β-MnO2/substrate interactions and the simultaneous surface property engineering pave the way to an efficient energy generation from abundant natural resources.

The synthesis of five novel cyclometalated platinum(II) compounds containing five different alkynyl-chromophores was achieved by the reaction of the previously synthesized Pt–Cl cyclometalated compound (1) with the corresponding RC≡CH by a Sonogashira reaction. It was observed that the spectral and photophysical characteristics of the cyclometalated platinum(II) complexes (Pt–Ar) are essentially associated with the platinum-cyclometalated unit. Room-temperature emission of the Pt–Ar complexes was attributed to phosphorescence in agreement with DFT calculations. Broad nanosecond (ns)-transient absorption spectra were observed with decays approximately identical to those obtained from the emission of the triplet state. From the femtosecond-transient absorption (fs-TA) data, two main excited-state decay components were identified: one in the order of a few picoseconds was assigned to fast intersystem crossing to populate the triplet excited-state and the second (hundreds of ns) was associated with the decay of the transient triplet state. In general, efficient singlet oxygen photosensitization quantum yields were observed from the triplet state of these complexes. peerReviewed

Oxygen is vital for energy metabolism in mammals and the variability of the concentration is considered a clinical alert for a wide range of metabolic malfunctions in medicine. In this article, we describe the development and application of a micro-needle implantable platinum-based electrochemical sensor for measuring partial pressure of oxygen in intramuscular tissue (in-vivo) and vascular blood (ex-vivo). The Pt-Nafion® sensor was characterized morphological and electrochemically showing a higher sensitivity of −2.496 nA/mmHg (−1.495 nA/μM) when comparing with its bare counterpart. Our sensor was able to discriminate states with different oxygen partial pressures (pO2) for ex-vivo (blood) following the same trend of the commercial gas analyzer used as standard. For in-vivo (intramuscular) experiments, since there is not a gold standard for measuring pO2 in tissue, it was not possible to correlate the obtained currents with the pO2 in tissue. However, our sensor was able to detect clear statistical differences of O2 between hyperoxia and hypoxia states in tissue.

Oxygen binding proteins (O(2)BIP) have been actively investigated for the past five decades due to their rich redox chemistry and function as O(2) carriers in blood cells, as well as their function as gasotransmitters and sensors that modulate cellular signaling. A series of meetings on the periodic advances in the knowledge gained in the field of globin structure and function are conducted typically on a biannual basis. In the fall of 2018, the XXth International Conference was conducted, and very important articles with breakthrough discoveries were presented and very enthusiastically discussed. This was yet another highly successful meeting in the series. Select articles from this meeting were recently reviewed, updated, and published over several issues of Antioxidants and Redox Signaling, as Forum articles communicating the latest advances in this important area of redox biology. This Forum editorial introduces these articles and highlights their scientific significance in advancing the field. Each of these articles grew out of lectures presented in the meeting, and appears either as an original contribution or a comprehensive review in the journal. Overall, the articles published in the Forum provide in-depth details on the recent developments in the field as well as point the way to future directions. These Forum articles thus serve as an important summary of progress and the ongoing direction of this field, and serve to highlight recent advances in our understanding of O(2)BIP.

A high work of breathing (WOB) associated with pulmonary hyperventilation during physical exercise, may limit sports performance in long-distance runners (e.g. marathon). The assessment of changes in WOB during maximal oxygen consumption test (V̇O2-máx.) allows knowing the intensity of exercise at which the higher WOB limits the delivery of nutrients and oxygen in muscles involved during locomotion. The non-invasive assessment of muscle oxygenation (SmO2) by the interpretation of wavelengths of near-infrared range (Near-Infrared Spectroscopy, NIRS) is a useful and new method to quantify muscle work, used at intercostal muscles (SmO2-m. intercostales) to the WOB, and at locomotor muscles (SmO2-m.vastus laterallis) to external load. Thus, as the intensity of exercise increases, a higher decrease in SmO2 is showed. However, until now is unknown how the ventilatory strategy used to achieve pulmonary hyperventilation affects the SmO2 of these muscle groups, whose muscle work affects them reciprocally through the metabolic reflex. As a report-case, we present the changes in SmO2-m.intercostales (WOB) and peripheral (SmO2-m.vastus laterallis) during the V̇O2-máx. test. in two competitive marathon runners with similar anthropometric characteristics, physical performance, training regimen and sports history. The objective is to give new information for identifying that the ventilatory strategy used during exercise can affect the local oxygenation in muscles with high demand during exercise. To evaluate this aspect, helping to coach improving the exercise performance in their athletes.

This thesis deals with an issue of Zander (Sander lucioperca) production in a recirculating aquaculture system RAS in different oxygen rates (50-80% O-, 80-110% Os and O+ 110-150%). Zander weighted W=22,98?15g was planted into two identical recirculating systems with different water temperature. SGR, FCR and FC of survival and general health condition of kept fish in hematology, biochemistry as well as stress indicators were evaluated. The results proved a negative influence of hypoxia (50-80%) on the food reception, growth and general survival of experimental fish kept in this environment in both the recirculating systems with water temperature 20 and 23°C. In the group O- kept in RAS 20°C, higher coefficient of FCR=1,11 was proved in comparison with group O (normoxia) and group O+ (hyperoxia), where no significant difference (p0,05) was recorded. The health condition showed a significant difference (p0,05) of O group in comparison with group O+ and O in RAS 20°C during the TBARS evaluation (brain, gills, muscle), assessing SOD in liver, and GPx (brain and muscle). By determining the HSI, SSI and VSI indexes, the significant differences (p0,05) of HSI and VSI for O+ and O groups in comparison with O- were proved.

[spa] INTRODUCCIÓN: La respuesta del lactato en sangre al ejercicio ha sido comúnmente utilizada en los ejercicios de resistencia (endurance exercises) para evaluar parámetros de aptitud aeróbica. Durante los ejercicios de resistencia de carga constante a una intensidad LT, se observa una estabilización en los niveles de lactato sanguíneo y en la respuesta cardiorrespiratoria, como también ocurre en ejercicios de resistencia. La captación de oxígeno (VO2) tiende a aumentar lentamente durante cualquier prueba de ejercicio de tasa de trabajo constante que involucre acidosis láctica sostenida, superando el componente primario iniciado al inicio del ejercicio. Esta respuesta de VO2, es conocida como "Componente lento de VO2" (VO2sc). Un VO2sc limitado podría ser un parámetro importante para determinar el rendimiento de resistencia. La eficiencia mecánica bruta ha sido considerada un parámetro fundamental en el análisis del rendimiento en los ejercicios de resistencia, sin embargo, hasta la fecha no ha sido evaluada en los ejercicios con resistencias en un protocolo constante a intensidad de LT. El objetivo es comparar el VO2sc, la eficiencia mecánica y ventilatoria, las respuestas metabólicas y cardiorrespiratorias y la fatiga mecánica entre el ciclismo y la HS durante una prueba de carga constante a intensidad del LT. METODOLOGIA: La tesis está compuesta por tres estudios experimentales. Se utilizó un protocolo de carga constante a intensidad LT en ejercicios con resistencias; media sentadilla (HS) y en ejercicios de resistencia; cicloergómetro (CYC) en adultos sanos. Se compararon las respuestas mecánicas, cardiorrespiratorias y la fatiga entre ambas modalidades de ejercicio. RESULTADOS: En relación al VO2, cociente respiratorio y respuesta al lactato, se observa un aumento significativo y sostenido desde S3 del VO2 en el ejercicio de HS (p0.001) El aumento ligero y continuo del EE se detectó a partir del S3 en HS (p 0.05) En relación a la fatiga en extremidades inferiores, a partir de los datos recogidos con el test CMJ, se observaron pérdidas significativas entre el pre y post test en la altura del salto (p 0.05). CONCLUSIONES: El ejercicio de la HS a carga constante a intensidad de LT induce un mayor EE y un incremento del VO2sc que el ejercicio del CYC. La eficiencia/economía es mayor en el ejercicio de la HS que en CYC. Un mejor conocimiento del comportamiento de VO2sc, EE, HSE y GME (generalmente utilizado en ejercicios de resistencia) nos permitiría aumentar el rendimiento y descubrir el potencial de los ejercicios con resistencias en un metabolismo predominantemente aeróbico, A pesar de que las respuestas cardiorrespiratorias fueron aumentadas en el ejercicio del cicloergómetro, la eficiencia ventilatoria fue igualmente eficaz en el ejercicio de HS que en el ejercicio en CYC en un metabolismo predominantemente aeróbico, lo que podría tener un impacto significativo en el ámbito clínico., [eng] INTRODUCTION: Knowledge of the oxygen uptake slow component (VO2sc), mechanical efficiency and ventilation, metabolic and cardiorespiratory responses and mechanical fatigue in resistance exercises allows us to increase performance and discover the potential of these exercises in a metabolism predominantly aerobic. METHODOLOGY: This research consists of three experimental studies applying a protocol of constant-load to lactate threshold intensity in healthy adults in resistance exercises through half squats (HS), and in endurance exercises through cycle ergometer (CYC). The mechanical, cardiorespiratory and fatigue responses between both forms of exercise were compared. RESULTS: Regarding VO2, respiratory quotient and lactate response, a significant and sustained increase in VO2 was observed in the HS exercise (p 0.001) and from S3 in HS (p 0.05). CONCLUSIONS: The HS exercise at a constant-load intensity of the useful life intensity induced an increase in VO2sc than the exercise of the CYC. The efficiency/economy is greater in the exercise of the HS than in CYC. Although the cardiorespiratory responses were increased in the cycle ergometer exercise, ventilation was equally effective in the HS and CYC exercises in a predominantly aerobic metabolism, which could have a significant impact in the clinical field.

Background Obstetric complications have long been retrospectively associated with a wide range of short- and long-term health consequences, including neurodevelopmental alterations such as those observed in schizophrenia and other psychiatric disorders. However, prospective studies assessing fetal well-being during pregnancy tend to focus on perinatal complications as the final outcome of interest, while there is a scarcity of postnatal follow-up studies. In this study, the cerebroplacental ratio (CPR), a hemodynamic parameter reflecting fetal adaptation to hypoxic conditions, was analyzed in a sample of monozygotic monochorionic twins (60 subjects), part of them with prenatal complications, with regard to (i) epigenetic age acceleration, and (ii) DNA methylation at genes included in the polygenic risk score (PRS) for schizophrenia, and highly expressed in placental tissue. Results Decreased CPR measured during the third trimester was associated with epigenetic age deceleration (β = 0.21, t = 3.362, p = 0.002). Exploration of DNA methylation at placentally expressed genes of the PRS for schizophrenia revealed methylation at cg06793497 (EP300 gene) to be associated with CPR (β = 0.021, t = 4.385; p = 0.00008, FDR-adjusted p = 0.11). This association was reinforced by means of an intrapair analysis in monozygotic twins discordant for prenatal suffering (β = 0.027, t = 3.924, p = 0.001). Conclusions Prenatal adverse environment during the third trimester of pregnancy is associated with both (i) developmental immaturity in terms of epigenetic age, and (ii) decreased CpG-specific methylation in a gene involved in hypoxia response and schizophrenia genetic liability. Electronic supplementary material The online version of this article (10.1186/s13148-019-0674-5) contains supplementary material, which is available to authorized users.

Background: The six-minute walk test (SMWT) is an easy-to-use test that measures walking distance. Aim: To elaborate an equation to estimate the maximum oxygen consumption (VO2 max) using the results of the SMWT. Material and Methods: Forty men and 40 women aged 22.5 ± 2 years, underwent a SMWT to measure the total walked distance and the recovery heart rate (RhR) Also, VO2 max was estimated from the maximal workload achieved in a cyclo-ergometer using the Storer test. A multivariate regression analysis resulted in a prediction equation that was validated with distributional assumptions of normality, independence and homoscedasticity. The limits of concordance of the predictive model were checked with the Bland-Altman diagram. Results: Body mass index (BMI), sex, RhR and total walked distance explained VO2 max variance by 3.4, 73.1, 17.9 and 32.8%, respectively. The prediction equation achieved was VO2 max (ml.min−1) = −3672.585 + (966.472 × Sex [1: female, 2: male]) + (-18.492 X RhR [beats.minute−1]) + (9.191 X Distance [m]) + (87.707 × BMI). The R2 of the equation was 0.91 (p < 0.01). Conclusions: This equation predicts VO2 max in Chilean university students according to sex, BMI, cardiovascular response and performance in the SMWT.

The Six-Minute Walking Test (SMWT) was completed just in few times in apparently healthy young individuals and university students, while the maximal volume of oxygen consumption (VO2max) prediction has not been taken into consideration. The aim of this study was to elaborate a prediction equation for VO2max from the heart rate recovery (HRR) after completion the SMWT. 127 young in the first stage completed the SMWT and Course Navette Test (CNT), 17 in the second stage (test-retest) completed the SMWT and CNT, and 20 subjects in the third stage completed the SMWT and Bruce test. All physical education students (PES) completions an informed consent. A significant correlation was observed between VO2max estimated trough the CNT and HRR after the SMWT (rho= -0.3; p= 0.001). The correlation between the same variables was r= -0.72 (p= 0.001) in the second stage, and a significant correlation (r= -0.65; p= 0.002) was observed between VO2max directly measured in Bruce test and HRR after the SMWT. From the correlation a prediction equation was elaborated is y= 92.468-(0.278*20-second-HRR) and the standard error of estimation (SEE) was 7.17 ml·kg-1·min-1. The HRR achieved after the SMWT may predict VO2max in PES. RESUMO O teste de caminhada de seis minutos (SMWT) foi concluído em poucas ocasiões em indivíduos jovens aparentemente saudáveis e estudantes universitarios, enquanto que a predição máxima do consumo de oxigênio (VO2max) não foi tomada em consideração. O objetivo deste estudo foi elaborar uma equação de predição para VO2max a partir da recuperação da freqüência cardíaca (HRR) após a realização do SMWT. 127 jovens na primeira etapa completaram o SMWT eo Course Navette Test (CNT), 17 na segunda etapa (teste-reteste) completaram o SMWT e CNT, e 20 sujeitos na terceira etapa completaram o teste SMWT e Bruce test. Todos os estudantes de educação física (PES) completam o consentimento informado. Observou-se uma correlação significativa entre o VO2máx estimado pela CNT e a HRR após o SMWT (rho= -0,3; p= 0,001). A correlação entre as mesmas variáveis foi r= -0,72 (p= 0,001) na segunda etapa e observou-se uma correlação significativa (r= -0,65; p= 0,002) entre VO2max medido diretamente no teste de Bruce e HRR após o SMWT. A partir da correlação foi elaborada uma equação de predição de y= 92,468-0,278*20-segundo-HRR) eo erro padrão de estimação (SEE) foi de 7,17 ml·kg-1·min-1. O HRR conseguido após o SMWT pode predizer VO2max no PES.

International audience; The first Italian translation of the Traité élémentaire de Chimie by Lavoisier was published in Naples, edited by two artillerymen in 1791. G.M. La Pira and L. Parisi translated this textbook with the practical aim of improving the learning of chemistry by the Royal artillery corps. This group of military students was the first in the South of Italy to have a laboratory at its disposal to study chemistry. The importance of chemistry for military purposes is abundantly evident, as we learned by the example of the laboratory of Lavoisier at the Arsenal, but, in the Kingdom of Naples, the artillerymen were the only scholars who had the means to study chemistry with a full range of resources.What are the differences between the original French text, the Neapolitan translation and the other Italian translations?In 1799, the short-lived Neapolitan Republic (January 23–June 19 1799) was in power, then, from 1806 to 1815 the Kingdom of Naples was subsumed during the “French decade.” It should be of particular interest for historians of chemistry to know what happened in the realm of science, teaching and research among the men of this military corps: during these crucial events, what happened to the artillerymen who were the first to translate and adopt the “nouvelle chimie”?; La première traduction du Traité élémentaire de chimie par Lavoisier a été publiée à Naples, éditée par deux artilleurs en 1791. G.M. La Pira et L. Parisi ont traduit ce manuel avec le but pratique d’améliorer l’enseignement de la chimie de l’artillerie royale. Cette catégorie d’étudiants a été la première au Sud de l’Italie à avoir bénéficié d’un laboratoire afin d’étudier la chimie. Cela souligne l’importance de la chimie consacrée à des fins militaires, comme cela a été démontré par le laboratoire de Lavoisier à l’Arsenal, mais, dans le Royaume de Naples, les artilleurs ont été les seuls savants qui ont pu travailler en chimie avec tous les moyens nécessaires.Quelles sont les différences entre le texte français original, la traduction napolitaine et les autres traductions en italien ?En 1799 il y eut la République napolitaine, de courte durée (23 janvier-19 juin 1799), puis, de 1806 à 1815, le Royaume de Naples a été gouverné par les Français, ce qu’on appelle le Decennio francese. Il devrait être très intéressant pour les historiens de la chimie de savoir ce qui est arrivé dans l’enseignement scientifique et l’univers de la recherche des corps militaires. Finalement, qu’est-il arrivé durant ces deux événements cruciaux aux artilleurs qui s’étaient distingués en ayant été les premiers à adopter la « nouvelle chimie » à Naples ?

Background: Patients with chronic obstructive pulmonary disease (COPD) may experience an acute worsening of respiratory symptoms that results in additional therapy; this event is defined as a COPD exacerbation (AECOPD). Hospitalization for AECOPD is accompanied by a rapid decline in health status with a high risk of mortality or other negative outcomes such as need for endotracheal intubation or intensive care unit (ICU) admission. Treatments for AECOPD aim to minimize the negative impact of the current exacerbation and to prevent subsequent events, such as relapse or readmission to hospital. Main body: In this narrative review, we update the scientific evidence about the in-hospital pharmacological and non-pharmacological treatments used in the management of a severe AECOPD. We review inhaled bronchodilators, steroids, and antibiotics for the pharmacological approach, and oxygen, high flow nasal cannulae (HFNC) oxygen therapy, non-invasive mechanical ventilation (NIMV) and pulmonary rehabilitation (PR) as non-pharmacological treatments. We also review some studies of non-conventional drugs that have been proposed for severe AECOPD. Conclusion: Several treatments exist for severe AECOPD patients requiring hospitalization. Some treatments such as steroids and NIMV (in patients admitted with a hypercapnic acute respiratory failure and respiratory acidosis) are supported by strong evidence of their efficacy. HFNC oxygen therapy needs further prospective studies. Although antibiotics are preferred in ICU patients, there is a lack of evidence regarding the preferred drugs and optimal duration of treatment for non-ICU patients. Early rehabilitation, if associated with standard treatment of patients, is recommended due to its feasibility and safety. There are currently few promising new drugs or new applications of existing drugs.

Guanosine, a guanine-based purine nucleoside, has been described as a neuromodulator that exerts neuroprotective effects in animal and cellular ischemia models. However, guanosine&rsquo, s exact mechanism of action and molecular targets have not yet been identified. Here, we aimed to elucidate a role of adenosine receptors (ARs) in mediating guanosine effects. We investigated the neuroprotective effects of guanosine in hippocampal slices from A2AR-deficient mice (A2AR&minus, /&minus, ) subjected to oxygen/glucose deprivation (OGD). Next, we assessed guanosine binding at ARs taking advantage of a fluorescent-selective A2AR antagonist (MRS7396) which could engage in a bioluminescence resonance energy transfer (BRET) process with NanoLuc-tagged A2AR. Next, we evaluated functional AR activation by determining cAMP and calcium accumulation. Finally, we assessed the impact of A1R and A2AR co-expression in guanosine-mediated impedance responses in living cells. Guanosine prevented the reduction of cellular viability and increased reactive oxygen species generation induced by OGD in hippocampal slices from wild-type, but not from A2AR&minus, mice. Notably, while guanosine was not able to modify MRS7396 binding to A2AR-expressing cells, a partial blockade was observed in cells co-expressing A1R and A2AR. The relevance of the A1R and A2AR interaction in guanosine effects was further substantiated by means of functional assays (i.e., cAMP and calcium determinations), since guanosine only blocked A2AR agonist-mediated effects in doubly expressing A1R and A2AR cells. Interestingly, while guanosine did not affect A1R/A2AR heteromer formation, it reduced A2AR agonist-mediated cell impedance responses. Our results indicate that guanosine-induced effects may require both A1R and A2AR co-expression, thus identifying a molecular substrate that may allow fine tuning of guanosine-mediated responses.

Thiosulfate effluents are generated in the photography and radiography industrial sectors, and in a plant in which thiosulfates are used to recover the gold and silver contained in ores. Similar effluents also containing thiosulfate are those generated from the petrochemical, pharmaceutical and pigment sectors. In the future, the amounts of these effluents may increase, particularly if the cyanides used in the extraction of gold and silver from ores are substituted by thiosulfates, or if the same happens to electronic scrap or in metallic coating processes. This paper reports a study of the oxidation of thiosulfate, with oxygen using copper (II) as a catalyst, at a pH between 4 and 5. The basic idea is to avoid the formation of tetrathionate and polythionate, transforming the thiosulfate into sulfate. The nature of the reaction and a kinetic study of thiosulfate transformation, by reaction with oxygen and Cu2+ at a ppm level, are determined and reported. The best conditions were obtained at 60 &deg, C, pH 5, with an initial concentration of copper of 53 ppm and an oxygen pressure of 1 atm. Under these conditions, the thiosulfate concentration was reduced from 1 g&middot, L&minus, 1 to less than 20 ppm in less than three hours.

[ES] En los últimos años se ha incrementado la población mundial reduciéndose la cantidad de recursos disponibles, haciéndose cada vez más necesaria la optimización de los mismos. Uno de los principales problemas que surgen es la necesidad de tratar las aguas procedentes de núcleos urbanos e industriales para su reutilización antes de ser vertida de nuevo a cauce público por su falta de calidad. El papel de los sistemas de control en las estaciones de depuración de aguas residuales (EDAR) sigue siendo de gran interés en la actualidad, debido principalmente a la variabilidad que presenta en agua residual afluente en lo que respecta a composición, caudal y carga contaminante. En el presente trabajo se estudia el comportamiento de una EDAR basada en el esquema de tratamiento propuesto en el modelo BSM1, pero con una peculiaridad: la duplicación del número de líneas de tratamiento mediante la duplicación del caudal afluente propuesto en dicho modelo. La EDAR ha sido implementada en el software de simulación DESASS y está formada por dos líneas en flujo pistón con 5 zonas (las primeras dos zonas anaerobias y las 3 últimas aerobias) más decantación secundaria, incorporando además un sistema de aireación. Al esquema de tratamiento se le añade un sistema de control que será implementado, calibrado y validado con el software LoDif BioControl, con el objetivo de optimizar el proceso de eliminación biológica de nitrógeno y materia orgánica., [CA] En els últims anys s'ha incrementat la població mundial reduint-se la quantitat de recursos disponibles, fent-se cada vegada més necessària l'optimització dels mateixos. Un dels principals problemes que sorgeix és la necessitat de tractar les aigües procedents de nuclis urbans i industrials per a la seua reutilització abans de ser abocada de nou a llit públic per la seua falta de qualitat. El paper dels sistemes de control a les estacions depuradores d'aigües residuals (EDAR) segueix estant en estudi en l'actualitat, sobretot pel que fa a la variabilitat que es presenta en l'aigua influent amb pertorbacions pel que fa a cabal i càrrega contaminant, juntament amb la diferent composició de les aigües residuals entrants. En el present treball es realitzen simulacions mitjançant una sèrie de programes que ens donaran una estratègia de control òptima per a l'eliminació del nitrogen de l'influent de manera biològica. Este en un tipus de planta de tractament basat en els reactors de flux pistó amb el model BSM1 però amb un canvi i el flux s'incrementa dues vegades perquè el model siga més paregut a la major quantitat d'EDAR. L'EDAR creada presenta dos línies en flux pistó amb 5 zones (les primeres dos zones anaeròbies i les 3 últimes aeròbies) més decantació secundària. A l'esquema de tractament se li afegeix un sistema de control que serà implementat, calibrat i validat amb el programa LoDif BioControl, amb l'objectiu d'optimitzar el procés de eliminació biològica de nitrogen i matèria orgànica., [EN] In recent years the world population has increased reducing the amount of available resources, becoming increasingly necessary to optimize them. One of the main problems that arise is the need to treat water from urban and industrial centers for reuse before being poured back into public waterways for their lack of quality. The role of control systems at wastewater treatment plants (WWTP) is still of interest for the scientific community, mainly due to the significant variability occurring in composition, flow and pollutant load of influent wastewaters. This study aims to evaluate the performance of a WWTP based on the layout proposed in the model BSM1, which was modified in order to account for peculiarities found in full-scale WWTPs. Specifically, the WWTP was design with two treatment lines by doubling the influent flow rate proposed in the before-mentioned model. The WWTP was implemented in the simulation software DESASS and consisted of two piston flow-based reactors with 5 zones (the first two zones were anaerobic and the last 3 zones were aerobic) and one secondary settler each line. The aeration system was also designed. The treatment schedule is added to a control system to be implemented, calibrated and validated with BioControl LoDif software, in order to optimize the biological process to removal nitrogen and organic matter.

The assessment of oxygen uptake (Vo2) in swimming is a complex and cumbersome procedure and still faces limitations imposed by the environment and the equipment. There are two different approaches to measure Vo2 in water: 1) continuous measurement during exercise with a respiratory snorkel, and 2) post-exercise measurement with gas collection via face or mouth masks. However, the use of swimming snorkels modifies swimming technique and hydrodynamics, resulting in lower swimming speeds and impossibility to execute diving starts and turns. To overcome these problems, the backward extrapolation of the oxygen recovery curve is often used for predicting Vo2peak during unimpeded swimming, but error can derive from a delay at the onset of recovery Vo2. In this thesis, we first assessed the validity of a mathematical model based on heart rate (HR) and post-exercise Vo2 kinetics for the estimation of Vo2 during exercise (study I). Then, to assess the validity of this technique in estimating Vo2peak, we compared 𝑉o2 measurements during supramaximal swimming with various commonly adopted estimation methods (study II) and distances (200- and 400-m) study III. We demonstrate that the new modelling procedure based on postexercise 𝑉𝑜2 and HR measurements is a valid and accurate technique for estimating Vo2peak in swimmers when used over a maximal 200- or 400-m test, indistinctly, and avoids the estimation bias produced by other commonly used methods. Therefore, this new procedure appears as the method of choice for assessing cardiorespiratory and metabolic fitness in competitive swimmers while swimming fully impeded., L'avaluació del consum d'oxigen (Vo2) en natació és un procediment complex i farragós degut a les limitacions imposades pel medi aquàtic i l'equipament. Hi ha dos procediments habituals per determinar del Vo2 en el medi aquàtic: 1) el mesurament continu del Vo2 mitjançant un sistema de tub respirador, i 2) mesuraments post exercici mitjançant l’ús de màscares facials o bucals. Tanmateix, l'ús de tubs respiratoris modifica la tècnica i la hidrodinàmica, fet que redueix la velocitat i impossibilita les fases subaquàtiques en sortides i viratges. Per superar aquests problemes s’ha utilitzat la retroextrapolació de la corba de recuperació del Vo2 per predir el 𝑉o2peak durant la natació lliure, però sovint es produeix un error d’estimació derivat d'un retard en l'inici de la recuperació del Vo2. En aquesta tesi, s’avalua un model matemàtic basat en la cinètica de la freqüència cardíaca (FC) i el Vo2 post exercici per l'estimació del Vo2 durant l’esforç (estudi I). Posteriorment, per avaluar la validesa del mètode en l'estimació del 𝑉o2peak, es van comparar els mesuraments de Vo2 durant proves de natació supramaximal amb diversos mètodes comunament utilitzats (estudi II) i en diferents distàncies (200 i 400 m) (estudi III). En aquesta investigació demostrem que el nou procediment de modelatge basat en mesures del Vo2 post exercici i en la cinètica de la FC és un mètode vàlid i acurat per estimar el 𝑉o2peak en nedadors en 200 o 400 m, indistintament, i evita el biaix d'estimació produït per altres mètodes. Per tant, aquest nou procediment es presenta com el mètode a escollir per avaluar, en condicions de natació completament lliure, les capacitats cardiorespiratòria i metabòlica en nedadors de competició.

INTRODUÇÃO: A medida da saturação venosa central de oxigênio (SvcO2) tem sido proposta como alternativa a saturação venosa mista (SvO2), com grau de concordância variável nos dados atualmente disponíveis. Esse estudo objetivou avaliar as possíveis diferenças entre a SvO2 e a SvcO2 ou saturação venosa atrial de oxigênio (SvaO2), com ênfase na interferência do débito cardíaco, e o impacto delas no manejo clínico do paciente séptico. MÉTODOS: Estudo prospectivo observacional em pacientes com choque séptico monitorizados com cateter de artéria pulmonar. Foi obtido sangue simultaneamente para determinação da SvcO2, SvO2 e SvaO2. Realizado testes de correlação linear (significativos se p

Background and Objective Twenty per cent of chronic obstructive pulmonary disease (COPD) patients are readmitted for acute exacerbation (AECOPD) within 30 days of discharge. The prognostic significance of early readmission is not fully understood. The objective of our study was to estimate the mortality risk associated with readmission for acute exacerbation within 30 days of discharge in COPD patients. Methods The cohort (n = 378) was divided into patients readmitted (n = 68) and not readmitted (n = 310) within 30 days of discharge. Clinical, laboratory, microbiological, and severity data were evaluated at admission and during hospital stay, and mortality data were recorded at four time points during follow-up: 30 days, 6 months, 1 year and 3 years. Results Patients readmitted within 30 days had poorer lung function, worse dyspnea perception and higher clinical severity. Two or more prior AECOPD (HR, 2.47; 95% CI, 1.51–4.05) was the only variable independently associated with 30-day readmission. The mortality risk during the follow-up period showed a progressive increase in patients readmitted within 30 days in comparison to patients not readmitted; moreover, 30-day readmission was an independent risk factor for mortality at 1 year (HR, 2.48; 95% CI, 1.10–5.59). In patients readmitted within 30 days, the estimated absolute increase in the mortality risk was 4% at 30 days (number needed to harm NNH, 25), 17% at 6-months (NNH, 6), 19% at 1-year (NNH, 6) and 24% at 3 years (NNH, 5). Conclusion In conclusion a readmission for AECOPD within 30 days is associated with a progressive increased long-term risk of death.

Thin-film oxygen sensors were prepared using the spin-coating technique, where a tris (4,7-diphenyl-1,10-phenanthroline) ruthenium(II) dichloride complex (RuDPP) in various solvents and silicones deposited on different substrates was used for the sensor production. By changing the spin-coating set-up parameters, homogeneous sensor coatings and the optimum sensor response to oxygen were studied – the sensors were exposed to various concentrations of oxygen within the range from 0% to 100 %. During the presented study, the optimum results were obtained when a 150 µL of sensor solution was applied to a Dataline foil using silicone E4 and a chloroform solvent. A spin coater with the following three rotation stages was used: 750/700 r/min for 3 s, 300 r/min for 3 s and 150 r/min for 4 s. The spin-coating technique has several benefits: it is fast, easy to use and appropriate for low-volume operations. It allows modifications and preparations of several sensor series using the minimum reagent consumption. However, the disadvantage of this technique also has to be mentioned, namely, an uneven film thickness in the radial direction. The film thickness mainly depends on the experimental set-up (volume, rotation time and speed, solvent viscosity and evaporation). Spin coating as an alternative and very flexible technique for an oxygen-sensor preparation is suggested for the laboratory-scale work, where the majority of experimental data could be used when other new coating methods are also researched and implemented. Izdelani so bili tankoplastni optični senzorji za kisik s tehniko spinskega nanosa. Pri tem so bile uporabljene različne koncentracije tris (4,7-difenil-1,10-fenantrolin) rutenij(II) diklorid kompleksa (RuDPP), različna topila, polimerni nosilci, silikoni in parametri spinskega prekritja. Naš namen je bil pripraviti najbolj homogen nanos senzorske raztopine in tako dobiti najbolj optimalne lastnosti senzorjev. Preučevali smo tudi vpliv hitrosti in časa vrtenja spinske naprave za prekrivanje na odziv senzorjev, saj so bili le-ti po izdelavi izpostavljeni različnim koncentracijam kisika v območju od0%do100%. Najboljši nanos senzorske raztopine smo dobili s senzorsko raztopino v kloroformu 150 µL z uporabo silikona E4 z nanosom na folijo Dataline. Pri tem smo uporabili tri različne stopnje vrtenja: 3 s pri 750/700 r/min, 3 s pri 300 r/min in 4 s pri 150 r/min. Prednost uporabe spinskega prekrivanja je, da je ta tehnika zelo hitra, enostavna za uporabo in je primerna za nanos majhnih prostornin. Omogoča izdelavo več serij senzorjev z različnimi lastnostmi ob minimalni porabi reagentov. Nanos senzorske raztopine na polimernem nosilcu v radialni smeri je v veliki meri odvisen od eksperimentalnih razmer: prostornine nanosa, hitrosti vrtenja, viskoznosti in hlapnosti topil. Metoda spinskega prekritja se je izkazala kot učinkovita metoda za nanos senzorskih raztopin v laboratorijskem merilu, vendar je po celotni senzorski površini težko pripraviti popolnoma homogen nanos, zato je za pripravo večjih količin identičnih senzorjev – po optimiranju vseh drugih eksperimentalnih razmer – smiselno preučiti še alternativne metode nanašanja.

Engineering the interface between different components of heterogeneous catalysts at nanometer level can radically alter their performances. This is particularly true for ceria-based catalysts where the interactions are critical for obtaining materials with enhanced properties. Here we show that mechanical contact achieved by high-energy milling of CeO2–ZrO2 powders and carbon soot results in the formation of a core of oxide particles wrapped in a thin carbon envelope. This 2D nanoscale carbon arrangement greatly increases the number and quality of contact points between the oxide and carbon. Consequently, the temperatures of activation and transfer of the oxygen in ceria are shifted to exceptionally low temperatures and the soot combustion rate is boosted. The study confirms the importance of the redox behavior of ceria-zirconia particles in the mechanism of soot oxidation and shows that the organization of contact points at the nanoscale can significantly modify the reactivity resulting in unexpected properties and functionalities.

The aim of this work is to elucidate, through density functional calculations, the role of the Si-O interface bonds on the structural, electronic and optical properties of Si nanodots in order to explain the peculiar properties of aged porous Si samples and heavily oxidized Si nanoparticles. For isolated dots we show that the presence of Si=O bond results in a strong reduction of the energy gap. For Si nanodots embedded in SiO 2 we show that both the Si-O bonding and the deformation of the cage play an important role.

OBJETIVO: Avaliar o efeito da nicotina na cicatrização da camada musculoaponeurótica da parede abdominal. MÉTODOS: Estudo experimental em que foram usados 16 ratos da raça Wistar pesando em média 210± 8g, separados aleatoriamente em 2 grupos de 8. Nos animais do grupo A foi implantado disco de nicotina (Nicotinel Ò) na dose de 5mg/Kg de peso/dia no subcutâneo da região dorsal, trocado a cada dois dias, a partir do 5º dia antes da operação em que foi feita laparotomia mediana de 5 cm, até o 10º dia de observação. No grupo B (controle) foram usados discos de celulose com o mesmo diâmetro. Tubo de silicone multiperfurado foi implantado no subcutâneo a 1cm da lesão da parede abdominal. A camada musculoaponeurótica e a pele foram suturadas com fio de nylon 5-0. No 10º dia pós-operatório foi colhido 1ml de líquido seroso do tubo de silicone por punção percutânea para dosagem de pO2 e os animais receberam dose letal de anestésico. Foi ressecado um segmento da camada musculoaponeurótica com 2cm de largura para tensiometria, em seguida processado e corado em HE e tricrômico de Masson para análise quantitativa dos dados histopatológicos em sistema digitalizado. A análise estatística foi feita pelo ANOVA e teste Newman-Keuls, com significância 0,05. RESULTADOS: No grupo A a pO2 do líquido tecidual atingiu o valor 17,75± 3,4 mmHg e no grupo B (controle) a pO2 = 40,75± 6,4 mmHg (p

OBJETIVO: Avaliar o efeito da nicotina na cicatrização da camada musculoaponeurótica da parede abdominal. MÉTODOS: Estudo experimental em que foram usados 16 ratos da raça Wistar pesando em média 210± 8g, separados aleatoriamente em 2 grupos de 8. Nos animais do grupo A foi implantado disco de nicotina (Nicotinel Ò) na dose de 5mg/Kg de peso/dia no subcutâneo da região dorsal, trocado a cada dois dias, a partir do 5º dia antes da operação em que foi feita laparotomia mediana de 5 cm, até o 10º dia de observação. No grupo B (controle) foram usados discos de celulose com o mesmo diâmetro. Tubo de silicone multiperfurado foi implantado no subcutâneo a 1cm da lesão da parede abdominal. A camada musculoaponeurótica e a pele foram suturadas com fio de nylon 5-0. No 10º dia pós-operatório foi colhido 1ml de líquido seroso do tubo de silicone por punção percutânea para dosagem de pO2 e os animais receberam dose letal de anestésico. Foi ressecado um segmento da camada musculoaponeurótica com 2cm de largura para tensiometria, em seguida processado e corado em HE e tricrômico de Masson para análise quantitativa dos dados histopatológicos em sistema digitalizado. A análise estatística foi feita pelo ANOVA e teste Newman-Keuls, com significância 0,05. RESULTADOS: No grupo A a pO2 do líquido tecidual atingiu o valor 17,75± 3,4 mmHg e no grupo B (controle) a pO2 = 40,75± 6,4 mmHg (pOBJETIVE: An experimental study was done to evaluate the effect of nicotine on the healing of abdominal wall. METHODS: Sexteen Wistar rats weighing 210± 8g were randomly separated into two groups of eight rats each. In the group A Nicotine (Nicotinel Ò) was implanted in the back subcutaneous 5mg/Kg each two days, begining at the fifth preoperative day. A 5cm median laparotomy was done, sutured with nylon 5-0 and the rats were observed in individual cages. The group B (control) didn’t use nicotine. A multiperfurated silicone tube was implanted subcutaneously near the abdominal sutured lesion. In the tenth postoperative day 1ml of serous liquid was harvested from the silicone tube and a pO2 dosage was done. The rats were killed with overdose of anesthetic. A 2cm width transversal segment of abdominal wall was submited to tensile strength test by a tensiometer. A biopsy of the sutured area including muscle, aporeurosis and peritoneum was processed for histopatologic analysis by a digitalised system. The data were processed by the ANOVA and Newman-Keuls tests, considering significant the differences when p

Drought is the main constraint on wheat yield in Mediterranean conditions. The photosynthesis, chlorophyll fluorescence and plant growth parameters of durum wheat ( Triticum turgidum , L. var. durum ) were compared at three [CO 2 ] (i.e., depleted 260 ppm, current 400 ppm and elevated 700 ppm) in plants subjected to two water regimes (i.e., well-watered WW, and mild water stress by drought or water deficit WS), during pre-anthesis, post-anthesis and the end of grain filling. We showed that [CO 2 ] effects on plants are modulated by water availability. Plants at depleted [CO 2 ] showed photosynthetic acclimation (i.e., up-regulation) and reduced plant biomass and Harvest Index, but depleted [CO 2 ] combined with WS has a more negative impact on plants with decreases in C assimilation and biomass. Plants at elevated [CO 2 ] had decreased plant growth and photosynthesis in response to a down-regulation mechanism resulting from a decrease in Rubisco and N content, but plants exposed to a combination of elevated [CO 2 ] and WS were the most negatively affected (e.g., on plant biomass).

Three new trinuclear heterometallic Ni(II)-Mn(II) complexes have been synthesized using a [NiL] metalloligand, where H2L = N,N'-bis(salicylidene)-1,3-propanediamine. The complexes [(NiL)2Mn(OCnn)2(CH3OH)2]·CH3OH (1), [(NiL)2Mn(OPh)2(CH3OH)2][(NiL)2Mn(OPh)2]·H2O (2), and [(NiL)2Mn(OSal)2(CH3OH)2]·2[NiL] (3) (where OCnn = cinnamate, OPh = phenylacetate, OSal = salicylate) have been structurally characterized. In all three complexes, in addition to the double phenoxido bridge, the two terminal Ni(II) atoms are linked to the central Mn(II) by means of a syn-syn bridging carboxylate, giving rise to a linear structure. Complexes 1 and 2 with Ni-O-Mn angles of 97.24 and 96.43°, respectively, exhibit ferromagnetic interactions (J(Ni-Mn) = +1.38 and +0.50 cm(-1), respectively), whereas 3 is antiferromagnetic (J(Ni-Mn) = -0.24 cm(-1)), having an Ni-O-Mn angle of 98.51°. DFT calculations indicate that there is a clear magneto-structural correlation between the Ni-O-Mn angle and J(Ni-Mn) values, which is in agreement with the experimental results.

Oxygen plays a crucial role in oenology. The oxygen leads to changes in the chemical and sensory profile of wines. On one hand, the impact of moderate oxygen exposure of red wine has a positive effect in its colour, aromatic bouquet and mouth-feel properties. On the other hand, oxygen has a negative effect on white wine’s quality, as well as the sensory and compositional levels. The purpose of this study was to quantify the dissolved oxygen in red and white wine, during different cellar operations such as racking, tartaric stabilization, filtering and bottling. The techniques that contribute most to the enrichment of oxygen in wine are: cold tartaric stabilization (2.29 mg/L, white wines), bottling (1.38 mg/L red wines and 1.11 mg/L white wines) and bag-in-box filling (2.47 mg/L red wines; 2.22 mg/L white wines). After identifying the most critical technical operations in wine making, preventive and corrective measures had to be taken to reduce the dissolved oxygen content of wines, as well as preventing their depreciation.