Platinum-rare earth nanoalloys have been predicted to be promising proton exchange membrane fuel cell (PEMFC) electrocatalysts for the cathodic oxygen reduction reaction (ORR). However, their ...implementation in PEMFCs is limited by the challenge of their preparation as carbon-supported nanostructures. Consequently, the practical structure–activity–stability trends for this class of nanoalloys remain largely unexplored. Herein, carbon-supported Pt–Nd nanoalloys as ORR electrocatalysts are described. The physical chemistry of selected electrocatalysts was extensively investigated by means of combined ex situ and operando techniques, which reveal the unique structural dynamics of Pt–Nd nanoalloys in a simulated PEMFC cathode environment. The experimental observations, supported by theoretical calculations, indicate that after initial significant structural modification in the early stage of operation, the ORR activity is mediated in the longer term by surface compressive strain rather than charge transfer between Pt and Nd. Such key operando structure–activity–stability relations underpin further optimization of carbon-supported Pt-rare earth nanoalloys as fuel cell cathode catalysts.
Gut colonization with multidrug-resistant
s (MDR-
) has reached worrisome levels worldwide. In this context, Escherichia ruysiae is a recently described species mostly found in animals. However, its ...spread and impact on humans is poorly understood. A stool sample from a healthy individual living in India was screened for the presence of MDR-
using culture-based methods. Colonies were routinely identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and phenotypically characterized by broth microdilution. Illumina and Nanopore whole-genome sequencing (WGS) platforms were implemented to generate a complete assembly.
genomes deposited in international databases were used for a core genome phylogenetic analysis. An extended-spectrum β-lactamase (ESBL)-producing E. coli strain (S1-IND-07-A) was isolated from the stool. WGS confirmed that S1-IND-07-A was indeed
, belonged to sequence type 5792 (ST5792), core genome (cg) ST89059, serotype O13/O129-:H56-like, clade IV phylogroup, and possessed five virulence factors. A copy of
and five other antimicrobial resistance genes (ARGs) were detected in a conjugative IncB/O/K/Z plasmid. A database search identified 70 further
strains from 16 countries (44, 15, and 11 strains isolated from animals, the environment, and humans, respectively). The core genome phylogeny revealed five major STs: ST6467, ST8084, ST2371, ST9287, and ST5792. Three out of the seventy strains possessed important ARGs: OTP1704 (
; ST6467), SN1013-18 (
; ST5792), and CE1758 (
; ST7531). These strains were of human, environmental, and wild animal origin, respectively.
may acquire clinically important ARGs and transmit them to other species. Due to its zoonotic potential, further efforts are needed to improve routine detection and surveillance across One Health settings.
Escherichia ruysiae is a recently described species of the cryptic clades III and IV of the genus Escherichia and is commonly found in animals and the environment. This work highlights the zoonotic potential of
, as it has been shown to colonize the human intestinal tract. Importantly,
may be associated with conjugative plasmids carrying clinically relevant antibiotic resistance genes. Therefore, it is important to closely monitor this species. Overall, this study highlights the need for improved identification of Escherichia species and continued surveillance of zoonotic pathogens in One Health settings.
The partial nitritation-anammox (PN-AMX) process applied to wastewaters with high NaCl concentration was studied until now using simulated media, without considering the effect of organic matter ...concentration and the shift in microbial populations. This research work presents results on the application of this process to the treatment of saline industrial wastewater. Obtained results indicated that the PN-AMX process has the capability to recover its initial activity after a sudden/acute salt inhibition event (up to 16 g NaCl/L). With a progressive salt concentration increase for 150 days, the PN-AMX process was able to remove the 80% of the nitrogen at 7–9 g NaCl/L. The microbiological data indicated that NaCl and ammonia concentrations and temperature are important factors shaping PN-AMX communities. Thus, the NOB abundance (Nitrospira) decreases with the increase of the salt concentration, while heterotrophic denitrifiers are able to outcompete anammox after a peak of organic matter in the feeding.
•Partial nitritation-anammox process treating industrial effluent with variable salt.•Sudden increase to 16 g NaCl/L: anammox inhibited but quickly recovered in 4 days.•After 150 adaptation days: good N removal values (80%, 0.2 gN/L·d) at 7–9 g NaCl/L.•Nitrite oxidizing activity suppressed for NaCl concentrations higher than 4–5 g/L.•A peak of organic matter developed heterotrophic bacteria that outcompeted anammox.
We explored the effect of discontinuing versus continuing angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) on clinical outcomes in patients with COVID-19 ...according to baseline disease severity.
We randomized 659 patients with a confirmed diagnosis of COVID-19 and classified them as having mild or moderate COVID-19 disease severity at hospital presentation using blood oxygen saturation and lung imaging. The primary outcome was the mean ratio of number of days alive and out of the hospital at 30 days according to disease severity.
At presentation, 376 patients (57.1%) had mild and 283 (42.9%) had moderate COVID-19. In patients with mild disease, there was no significant difference in the number of days alive and out of the hospital between ACEI/ARB discontinuation (mean 23.5 SD 6.3 days) and continuation (mean 23.8 SD 6.5 days), with a mean ratio of 0.98 (95% CI 0.92-1.04). However, in patients with moderate disease, there were fewer days alive and out of the hospital with ACEI/ARB discontinuation (mean 19.6 SD 9.5 days) than continuation (mean 21.6 SD 7.6 days), with a mean ratio of 0.90 (95% CI 0.81-1.00; P-interaction = .01). The impact of discontinuing versus continuing ACEIs/ARBs on days alive and out of hospital through 30 days differed according to baseline COVID-19 disease severity.
Unlike patients with mild disease, patients with moderate disease who continued ACEIs/ARBs had more days alive and out of hospital through 30 days than those who discontinued ACEIs/ARBs. This suggests that ACEIs/ARBs should be continued for patients with moderate COVID-19 disease severity.
ClinicalTrials.gov (NCT04364893).
The development of woven composites has led to an increase in the number of investigations on the uncertainty of the intricate fibre architecture and its effect on the mechanical properties. The ...present work proposes a simplified method to study fibre architecture by means of microscopy analysis of cross-sections. The approach is based on multiscale numerical simulations including mesoscale and macroscale models, in which the mesoscale model provide the mechanical parameters exploited as input to the macroscale model, which produces reliable and efficient outputs in engineering applications. Two types of distributions, uniform and normal, were used in the macroscale model to describe the variable fibre architecture parameters, and the normal distribution was found to be more suitable. Both aramid-fibre and glass-fibre woven composites, under two different loading conditions, tension and shear, were investigated, and the results showed the importance of considering the shear behaviour in engineering applications.
Predicting the perforation limit of composite laminates is an important design aspect and is a complex task due to the multi-mode failure mechanism and complex material constitutive behaviour ...required. This requires high-fidelity numerical models for a better understanding of the physics of the perforation event. This work presents a numerical study on the perforation behaviour of a satin-weave S2-glass/epoxy composite subjected to low-velocity impact. A novel strain-rate-dependent finite-discrete element model (FDEM) is presented and validated by comparison with experimental data for impacts at several energies higher and lower than their perforation limit. The strain rate sensitivity was included in the model by developing a novel user-defined material model, which had a rate-dependent bilinear traction separation cohesive behaviour, implemented using a VUSDFLD subroutine in Abaqus/Explicit. The capability of the model in predicting the perforation limit of the composite was investigated by developing rate-sensitive and insensitive models. The results showed that taking the strain rate into account leads to more accurate predictions of the perforation limit and damage morphology of the laminate subjected to impacts at different energies. The experimental penetration threshold of 89 J was estimated as 79 J by the strain-rate-sensitive models, which was more accurate compared to 52 J predicted by the strain-rate-insensitive model. Additionally, the coupling between interlaminar and intralaminar failure modes in the models led to a more accurate prediction of the delamination area when considering the rate sensitivity.
Rapid identification of existing respiratory viruses in biological samples is of utmost importance in strategies to combat pandemics. Inputting MALDI FT-ICR MS (matrix-assisted laser ...desorption/ionization Fourier-transform ion cyclotron resonance mass spectrometry) data output into machine learning algorithms could hold promise in classifying positive samples for SARS-CoV-2. This study aimed to develop a fast and effective methodology to perform saliva-based screening of patients with suspected COVID-19, using the MALDI FT-ICR MS technique with a support vector machine (SVM). In the method optimization, the best sample preparation was obtained with the digestion of saliva in 10 μL of trypsin for 2 h and the MALDI analysis, which presented a satisfactory resolution for the analysis with 1 M. SVM models were created with data from the analysis of 97 samples that were designated as SARS-CoV-2 positives versus 52 negatives, confirmed by RT-PCR tests. SVM1 and SVM2 models showed the best results. The calibration group obtained 100% accuracy, and the test group 95.6% (SVM1) and 86.7% (SVM2). SVM1 selected 780 variables and has a false negative rate (FNR) of 0%, while SVM2 selected only two variables with a FNR of 3%. The proposed methodology suggests a promising tool to aid screening for COVID-19.
Carbon-supported platinum–rare earth nanoalloys are promising electrocatalysts for the oxygen reduction reaction. However, their structure–activity–stability trends are poorly understood. Herein, we ...followed the evolution of Pt–Nd/C nanoalloys during the electrochemical surface conditioning, i.e., prior to the initial evaluation of electrocatalytic activity, and observed that their compositional, morphological, and structural ex situ properties are considerably modified by the electrochemical activation step. It is these stabilized properties, therefore, that should be considered when discussing the electrocatalyst beginning-of-life state for the structure–activity–stability relationships rather than those determined ex situ on the as-synthesized electrocatalyst.
The needs of people with dementia (PWD) have not been assessed in any Latin American country. Several European countries have already related unmet needs with quality of life, caregiver's age, ...burden, stress, anxiety and depression. The aim of this study was to identify met and unmet needs in Chilean older adults with dementia and to determine if those needs were associated with PWD's, their informal caregivers' and social factors.
This was a cross-sectional study. One-hundred and sixty-six informal caregivers and their care recipients were interviewed. PWD was assessed about cognitive function and their caregivers answered instruments about PWD's needs, functional status and behavioral and psychological symptoms. Caregiver's burden, depression, anxiety and social support were also evaluated. A stepwise multiple linear regression analysis was performed to determine predictors of unmet needs in Chilean PWD.
The most frequent met needs were "Looking after home" (81.3%%), "Food" (78.9%) and "Selfcare" (75.3%). Most common unmet needs were "Daily living activities" (39.2%), "Company" (36.1%), and "Memory" (34.9%). Caregivers' lower age was correlated to a higher number of PWD's unmet needs (r
= -.216; p < 0.005). Higher PWD's dependence was associated with higher number of unmet needs (r
= .177; p < 0.05). The best predictors of unmet needs were caregivers' low level of social support, high burden, young age and high level of anxiety.
It is necessary to address psychological and social needs of PWD. The fact that PWD's unmet needs were associated mostly with caregivers' factors, highlights the importance of considering both, the PWD and their informal caregivers as targets of institutional support. It is expected that recently launched national public policies decrease PWD's unmet needs by the provision of new services for them and their informal caregivers.
has a high level of active chemicals that are useful in the food industry, and they have antibacterial and food preservation properties. The characterization of
seed oil (MOS) may vary due to ...agronomic and environmental factors. Therefore, it was necessary to know the composition of lipids present in our oil extracted under pressing at 180 °C and thus determine if it is suitable to produce a biopackaging. Within the characterization of the oil, it was obtained that MOS presented high-quality fatty acids (71% oleic acid) with low values of acidity (0.71 mg KOH/g) and peroxide (1.74 meq O
/kg). Furthermore, MOS was not very sensitive to lipoperoxidation by tert-butyl hydroperoxide (tBuOOH) and its phenolic components, oleic acid and tocopherols, allowed MOS to present a recovery of 70% after 30 min of treatment. Subsequently, a biopackaging was developed using a multiple emulsion containing corn starch/carboxymethylcellulose/glycerol/MOS, which presented good mechanical properties (strength and flexibility), transparency, and a barrier that prevents the transfer of UV light by 30% and UV-C by 98%, as well as a flux with the atmosphere of 5.12 × 10
g/ m.s. Pa that prevents moisture loss and protects the turkey ham from O
. Hence, the turkey ham suffered less weight loss and less hardness due to its preservation in the biopackaging.
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