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Au/ZrO2 catalysts (1.5 wt% Au loading) undergone to a final calcination at different temperature (423, 573, 773 and 923 K) to opportunely modulate the Au size were proven to be highly active and selective in furfural oxidative esterification to methyl-2-furoate. The catalysts were tested according to previously optimized reaction conditions, employing O2 as benign oxidant and without any base co-catalyst. The strong dependence of the catalytic activity on the Au size was previously ascribed to the presence of Au clusters able to dissociate O2 and producing atomic O that can activate methanol. However, despite the absence of clusters, also the catalysts containing larger Au nanoparticles were active, even if conversion and selectivity were remarkably lower if compared to the other samples. The nature and the role of Au active sites exposed at the surface of clusters and nanoparticles were then investigated by HR-TEM, CO chemisorption and FTIR spectroscopy of adsorbed CO, molecular oxygen, methanol and furfural to establish structure-activity relationships. Metal nanoparticles can activate oxygen and form superoxo species and atomic O, whereas experiments performed on the pre-hydrated samples revealed that Au perimeter sites at the metal-support interface play a key role in methanol activation during furfural oxidative esterification.

Aluminium based metal matrix composites have drawn more attraction due to their improved properties in structural applications for the past two decades. The fatigue behaviour of composite materials needs to be studied for their structural applications. In this work, powder metallurgy based aluminium (AA2014) alloy reinforced with micro and nano-sized alumina particles were fabricated and consolidated with the hot extrusion process. The evaluation of mechanical properties in the extruded composite was carried out. This composite was subjected to low cycle fatigue test with a constant strain rate. Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) images were used to evaluate the fatigue behaviour of aluminium-nano composite samples. Enhanced mechanical properties were exhibited by the nano alumina reinforced aluminium composites, when compared to the micron sized alumina reinforced composites. The failure cycle is observed to be higher for the nano alumina reinforced composites when compared with micron sized alumina composites due to a lower order of induced plastic strain.

Ecological studies searching for drivers of biodiversity variation have frequently focused on taxonomic richness. However, more aspects of biodiversity, namely diversity facets can be considered to properly assess biotic-environment relationships. Here, we explore the environmental factors that could control the four biodiversity facets of aquatic Coleoptera from 93 regionally sampled Patagonian ponds. We also explore which are the ponds with high diversity values of all facets to prioritize them with a high conservation value. We fitted generalized additive models (GAM) to test relationships among environment (i.e., local and climatic variables) and aquatic beetles diversity facets (i.e., richness (SD), functional diversity (FD), phylogenetic diversity (PD), and local contribution to local beta diversity (LCBD). Climatic drivers were the most important predictors of beetle diversity facets, which exhibited linear and nonlinear responses. Thus, ponds from warmer Patagonia exhibited the highest values of SD and PD, whereas LCBD also peaked on colder sites suggesting that ponds under extreme temperatures sustain unique beetle assemblages. Moreover, ponds located in areas with higher precipitation variability exhibit the highest values of LCBD (i.e., unique assemblages). This result in addition to arid conditions in Patagonia prevailing since 16 m.y.a made us think that Patagonian beetle pond-dwellers are basally adapted to aridity. We calculated an index that summarizes the four facets patterns, to assign high conservation value to those ponds with higher index values. The relative importance of each facet varies from pond to pond. Hence, this multifaceteded approach not only allows us to identify priority areas for biodiversity conservation but also focuses on the importance of including multiple facets to understand biodiversity spatial patterns.

Background: Elevated resting heart rate is a risk factor for cardiovascular events., Objective: The purpose of this study was to investigate the clinical significance of nocturnal heart rate (nHR) and 24-hour mean heart rate (24h-HR) obtained by continuous remote monitoring (RM) of implantable devices., Methods: We analyzed daily-sampled trends of nHR, 24h-HR, and physical activity in patients on β-blocker therapy for chronic heart failure and with implantable cardioverter-defibrillators or cardiac resynchronization therapy defibrillators (CRT-Ds). Patients were grouped by average nHR and 24h-HR quartile during follow-up to estimate the respective incidence of nonarrhythmic death and device-treated ventricular tachycardia/fibrillation (VT/VF)., Results: The study cohort included 1330 patients (median age 69 years [interquartile range 61-77 years]; 41% [n = 550] with CRT-D; median follow-up 25 months [interquartile range 13-42 months]). Compared with patients in the lowest nHR quartile (≤57 beats/min) group, patients in the highest quartile group (>65 beats/min) had an increased risk of nonarrhythmic death (adjusted hazard ratio [AHR] 2.25; 95% confidence interval [CI] 1.13-4.50; P = .021) and VT/VF (AHR 1.98; 95% CI 1.40-2.79; P < .001) and were characterized by the lowest level of physical activity (P ≤ .0004 vs every other nHR quartiles). The highest 24h-HR quartile group (>75 beats/min) showed an increased risk of VT/VF (AHR 2.13; 95% CI 1.52-2.99; P < .001) and a weaker though significant association with nonarrhythmic mortality (AHR 1.80; 95% CI 1.00-3.22; P = .05) as compared with the lowest 24h-HR quartile group (≤65 beats/min)., Conclusion: In remotely monitored patients with implantable cardioverter-defibrillator/CRT-D on β-blocker therapy for heart failure, elevated heart rates (nHR >65 beats/min and 24h-HR >75 beats/min) were associated with increased mortality and VT/VF risk. nHR showed a stronger association than 24h-HR with worst prognosis and lowest physical activity., (Copyright © 2022 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Objective: Sensorimotor integration is a crucial process for adaptive behaviour and can be explored non-invasively with a conditioned transcranial magnetic stimulation (TMS) paradigm - i.e. short-latency afferent inhibition (SAI). To gain insight into the sensorimotor integration phenomenon, we used two different approaches to combine peripheral and cortical stimulation in the SAI paradigm, measuring not only the latency of low frequency somatosensory evoked potentials (SEPs) but also the peaks of high frequency oscillations (HFOs) underlying SEPs., Methods: The interstimulus intervals (ISIs) between the electrical stimulation of the median nerve and the motor cortex magnetic stimulation were determined relative to the latency of the earliest SEPs cortical potential (N20) or the HFOs peaks. In particular, the first and last negative and positive peaks of HFOs were extracted through a custom-made MATLAB script., Results: Thirty-three healthy subjects participated in this study. We found out that muscle responses after TMS were suppressed when ISIs were comprised between -1 to +3 ms relative to the N20 peak and at all ISIs relative to HFOs peaks, except for the first negative peak., Conclusions: Coupling peripheral and cortical stimulation at early interstimulus intervals - before the SEPs N20 peak - may modulate muscle response., Significance: Our findings confirm that afferent inhibition is produced both through a direct (thalamus-motor cortex) and indirect (thalamus-somatosensory-motor cortex) pathway., (Copyright © 2022 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Formaldehyde emission is an intrinsic property derived from aldehyde-based resin that is used in wood-based composites. To reduce formaldehyde emission from plywood, the composite catalyst of tourmaline-titanium dioxide (T-TiO 2 ) was fabricated by the sol-gel method. Furthermore, the impregnated paper loaded with the T-TiO 2 composite catalyst was used to decorate the surface of 5-layer poplar plywood. The physicochemical structure, photocatalytic activity of T-TiO 2 composite catalyst and its mechanism of degrading gaseous formaldehyde and generating air negative ions were assessed. The results discovered that the synergistic influence of the tourmaline and TiO 2 anatase nanocrystals achieved good photodegradation of the gaseous formaldehyde. The neat T(20%)-TiO 2 catalyst offered a higher formaldehyde removal efficiency (92.2%) than other catalysts, possessing 800 ions/cm 3 of air negative ions concentration after 10-h visible light irradiation. The poplar plywood with a load of 3% T(20%)-TiO 2 catalyst can stably induce the degradation formaldehyde into air negative ions with a concentration of 1200 ions/cm 3 in visible light. The impregnation process of paper was feasible to be industrialized and the decorated wood-based composites can be widely applied in the furniture industry., (Copyright © 2021 Elsevier B.V. All rights reserved.)

DNA methylation is one of the most extensively studied epigenetic marks. It is involved in transcriptional gene silencing and plays important roles during mammalian development. Its perturbation is often associated with human diseases. In mammalian genomes, DNA methylation is a prevalent modification that decorates the majority of cytosines. It is found at the promoters and enhancers of inactive genes, at repetitive elements, and within transcribed gene bodies. Its presence at promoters is dynamically linked to gene activity, suggesting that it could directly influence gene expression patterns and cellular identity. The genome-wide distribution and dynamic behaviour of this mark have been studied in great detail in a variety of tissues and cell lines, including early embryonic development and in embryonic stem cells. In combination with functional studies, these genome-wide maps of DNA methylation revealed interesting features of this mark and provided important insights into its dynamic nature and potential functional role in genome regulation. In this review, we discuss how these recent observations, in combination with insights obtained from biochemical and functional genetics studies, have expanded our current knowledge about the regulation and context-dependent roles of DNA methylation in mammalian genomes., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Glucokinases (Glks) are enzymes widely distributed in all three domains of life. They are located at the beginning of the glycolytic pathway and are responsible for the glucose phosphorylation from various phosphate group donors such as ATP, ADP and polyphosphate. So far, there are eight crystallized Glks, and at least one belongs to each of the three reported Glk families. Structural studies have elucidated the mechanism for Glk action and multimerization. Cloning, overexpression and biochemical characterization have demonstrated the wide diversity of these enzymes. As reported for various microorganisms, in addition to their catalytic activity, some Glks, possessing ROK (Repressor Orf Kinases) motifs, also display a regulatory role. This function has been associated to the mechanisms of carbon catabolite regulation, morphological differentiation and antibiotic production. The present review covers the classification, detailed tertiary structure, mechanism of action, biochemical characterization and some regulatory aspects of bacterial Glks., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Daily plasma progesterone (P(4)) was determined during one estrous cycle of 19 cows and 18 heifers of four different breeds: Holstein (H), Brahman (B), Carora-type (C) and crossbred (CB) females. Estrus detection was made by visual observation and using a teaser bull with a chin-ball marker. The P(4) profiles showed no differences among groups. In Group 1 (H), P(4) levels ranged from 0.5 ng/ml plasma on the day of estrus (Day 0) to 5.1 ng/ml at the luteal phase peak (Day 13). In Group 2 (B), P(4) levels ranged from 0.5 ng/ml on Day 0 to 9.2 ng/ml on Day 13. In Groups 3 (C) and 4 (CB), P(4) levels ranged from 0.5 ng/ml, on Day 0, to 13.7 ng/ml on Day 12 and 8.8 ng/ml on Day 13. These last two groups were moved to the same location and then compared. It was found that P(4) concentrations were significantly higher (P < 0.025) in Group 3 between Days 7 and 14 of the estrous cycle. In all groups, P(4) levels were lower than 1 ng/ml one day before the next estrus, and levels of 0.4, 0.5, 0.4 and 0.4 ng/ml were obtained the day of estrus in Groups 1 to 4, respectively. Results indicated that the pattern of P(4) for each one of the groups was similar to those reported by other investigators.