Piezoelectric nanomaterials open new avenues in driving green catalysis processes (e.g., H2 evolution from water) through harvesting mechanical energy, but their catalytic efficiency is still ...limited. The predicted enormous piezoelectricity for 2D SnSe, together with its high charge mobility and excellent flexibility, renders it an ideal candidate for stimulating piezocatalysis redox reactions. In this work, few‐layer piezoelectric SnSe nanosheets (NSs) are utilized for mechanically induced H2 evolution from water. The finite elemental method simulation demonstrates an unprecedent maximal piezoelectric potential of 44.1 V for a single SnSe NS under a pressure of 100 MPa. A record‐breaking piezocurrent density of 0.3 mA cm−2 is obtained for SnSe NSs‐based electrode under ultrasonic excitation (100 W, 45 kHz), which is about three orders of magnitude greater than that of reported piezocatalysts. Moreover, an exceptional H2 production rate of 948.4 µmol g−1 h−1 is achieved over the SnSe NSs without any cocatalyst, far exceeding most of the reported piezocatalysts and competitive with the current photocatalysis technology. The findings not only enrich the potential piezocatalysis materials, but also provide useful guidance toward high‐efficiency mechanically driven chemical reactions such as H2 evolution from water.
SnSe nanosheets are used for mechanically driven H2 evolution through water splitting. Benefiting from the highest predicted piezoelectric coefficients among all 2D materials, excellent flexibility, and superior charge mobility, the SnSe nanosheets demonstrate exceptional piezocurrent density (0.3 mA cm−2) and H2 evolution activity (948.4 µmol g−1 h−1) without cocatalyst under ultrasonic vibration (100 W, 45 kHz).
The levels of cell free circulating tumor DNA (ctDNA) in plasma correlated with treatment response and outcome in systemic lymphomas. Notably, in brain tumors, the levels of ctDNA in the ...cerebrospinal fluid (CSF) are higher than in plasma. Nevertheless, their role in central nervous system (CNS) lymphomas remains elusive. We evaluated the CSF and plasma from 19 patients: 6 restricted CNS lymphomas, 1 systemic and CNS lymphoma, and 12 systemic lymphomas. We performed whole exome sequencing or targeted sequencing to identify somatic mutations of the primary tumor, then variant-specific droplet digital PCR was designed for each mutation. At time of enrolment, we found ctDNA in the CSF of all patients with restricted CNS lymphoma but not in patients with systemic lymphoma without CNS involvement. Conversely, plasma ctDNA was detected in only 2/6 patients with restricted CNS lymphoma with lower variant allele frequencies than CSF ctDNA. Moreover, we detected CSF ctDNA in 1 patient with CNS lymphoma in complete remission and in 1 patient with systemic lymphoma, 3 and 8 months before CNS relapse was confirmed; indicating CSF ctDNA might detect CNS relapse earlier than conventional methods. Finally, in 2 cases with CNS lymphoma, CSF ctDNA was still detected after treatment even though a complete decrease in CSF tumor cells was observed by flow cytometry (FC), indicating CSF ctDNA better detected residual disease than FC. In conclusion, CSF ctDNA can better detect CNS lesions than plasma ctDNA and FC. In addition, CSF ctDNA predicted CNS relapse in CNS and systemic lymphomas.
The aim of this work is to find out the most suitable method for detecting and analyzing accurately the formation conditions of secondary phases, particularly Sigma-phase (σ-phase) and Chi-phase ...(χ-phase) in duplex stainless steels (UNS S32205 and UNS S32750). The microstructure was characterized after a solution annealing at 1080°C followed by an isothermal heating at 830°C for different time ranges, ranging from 1min to 9h, in order to enlighten the controversial point concerning the mechanism of χ-phase nucleation in relation with the σ-phase. Etched samples were observed using optical microscopy (MO), and scanning electron microscopy (FESEM) with a backscattered electron detector (BSE) was used on unetched samples. Compositional microanalysis (EDS) was carried out for identifying the different phases present in the steels. Sigma phase was easily observed using different etching procedures, whereas χ-phase was only clearly detected with FESEM–BSE on unetched samples. The compositional analyses showed that the molybdenum content in χ-phase almost doubles the content of this element in σ-phase, and as a result the kinetics of nucleation and growth were also found to be remarkably faster when the alloy content in the steel is higher. In addition, chromium nitrides and carbides were also observed to precipitate as a result of the heat treatments and, in the case of the chromium nitrides, they act as a favorable site for the nucleation of σ-phase and χ-phase.
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•Microscopy was used on heat treated duplex steels for microstructure identification.•FESEM–BSE observation on unetched samples provided the best contrast between phases.•Analyses of carbides, nitrides, chi and sigma phases were possible by EDS and WDS.•Chromium nitrides act as favorable site for the nucleation of chi and sigma phases.•Secondary phases nucleation kinetics are faster in superduplex than in duplex steels.
A superhydrophobic CuFeCo powder alloy, obtained by combining high-energy ball milling (HEBM) and liquid phase deposition (LPD), was used to remove high-density polyethylene fibres from water. After ...48 h of HEBM, CuFeCo solid solution powder with ferromagnetic properties was obtained. High-resolution transmission electron microscopy showed a crystallite size of 20 nm, confirming its nanostructure. The metallic CuFeCo powder surface was functionalised with dodecanoic acid to confer superhydrophobicity (water contact angle = 162 ± 1°) and superoleophilicity (oil contact angle ~ 0°). Taking advantage of its superwettable properties, superhydrophobic CuFeCo particles were used to capture microplastics (270 µm < size < 1240 µm), which is an innovative application of superhydrophobic materials. This study demonstrates an innovative way of using superhydrophobic materials in environmental applications such as the removal of solid pollutants like microplastics.
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•Nanostructured CuFeCo particles acquire superhydrophobicity through functionalisation with dodecanoic acid.•The superhydrophobic CuFeCo particles separate oil from water.•The superhydrophobic CuFeCo particles capture microplastics at different concentrations.
This article analyzes how the intensification of neoliberal policies and the use of privatization to govern access to the ocean and its resources are producing the conditions for the dispossession of ...Indigenous fishing customary rights as well as resistance practices that interrupt neoliberal policies. This article highlights the role of actors beyond the state in producing the specific junctures at which the vocation of the Indigenous peoples in the Tehuantepec Isthmus in the state of Oaxaca, Mexico, is changed to become a “center of sustainable development.”
•“Green” neoliberalism adversely affects people and resources.•Neoliberal policies have increasingly severe impacts on Indigenous fishing.•Neoliberal visions of development are contested and resisted.
El presente artículo muestra los resultados de un estudio centrado en reconocer los cambios culturales, producto de la incursión de las tecnologías en la sociedad actual y su efecto en la ...ciberciudadanía. El planteamiento metodológico, las tradiciones y prospectivas de esta investigación de orden mixto, tanto en sus enfoques como en sus diseños, han sido implementadas por investigadores participantes de Colombia, Ecuador, Chile y Brasil presentando resultados que permitieron clasificar, ahora, tres amplios campos de investigación que permiten descifrar las nuevas concepciones de lo que implica investigar en tecnologías y sociedad
Background
Amoxicillin (AX) is nowadays the β‐lactam that more frequently induces immediate allergic reactions. Nevertheless, diagnosis of AX allergy is occasionally challenging due to risky in vivo ...tests and non‐optimal sensitivity of in vitro tests. AX requires protein haptenation to form multivalent conjugates with increased size to be immunogenic. Knowing adduct structural features for promoting effector cell activation would help to improve in vitro tests. We aimed to identify the optimal structural requirement in specific cellular degranulation to AX using well‐precised nanoarchitectures of different lengths.
Method
We constructed eight Bidendron Antigens (BiAns) based on polyethylene glycol (PEG) linkers of different lengths (600–12,000 Da), end‐coupled with polyamidoamine dendrons that were terminally multi‐functionalized with amoxicilloyl (AXO). In vitro IgE recognition was studied by competitive radioallergosorbent test (RAST) and antibody–nanoarchitecture complexes by transmission electron microscopy (TEM). Their allergenic activity was evaluated using bone marrow‐derived mast cells (MCs) passively sensitized with mouse monoclonal IgE against AX and humanized RBL‐2H3 cells sensitized with polyclonal antibodies from sera of AX‐allergic patients.
Results
All BiAns were recognized by AX‐sIgE. Dose‐dependent activation responses were observed in both cellular assays, only with longer structures, containing spacers in the range of PEG 6000–12,000 Da. Consistently, greater proportion of immunocomplexes and number of antibodies per complex for longer BiAns were visualized by TEM.
Conclusions
BiAns are valuable platforms to study the mechanism of effector cell activation. These nanomolecular tools have demonstrated the importance of the adduct size to promote effector cell activation in AX allergy, which will impact for improving in vitro diagnostics.
The use of BiAns demonstrates the importance of adduct size and distance between determinants to promote effector cell activation in AX allergy. Optimal effector cell activation is showed with the biggest BiAns, which involves a greater number of immunocomplex and antibodies. BiAns are versatile nanoplatforms that can be applied to different allergies, valuable for improving in vitro allergy tests. Abbreviations: AX, amoxicillin; AXO, amoxicilloyl; BiAn, bidendron antigen; MoAb, monoclonal antibody; RBL, rat basophilic leukemia cell
On 11 March 2020 the SARS-CoV-2 virus was officially declared a pandemic and measures were set up in various countries to avoid its spread among the population. This paper aims to analyse the ...perception of risk of COVID-19 infection in the Spanish population. A cross-sectional, descriptive observational study was conducted with a total of 16,372 Spanish participants. An online survey was used to gather data for 5 consecutive days over the compulsory lockdown period which was established after the state of emergency was declared. There is an association between socio-demographic variables and risk perception, and a very strong relationship between this perception and contact and direct experience with the virus in a family, social or professional setting. We also found that compared to working from home, working outside the home increased the perception of risk of infection and the perception of worsening health. Understanding the public perception of the risk of COVID-19 infection is fundamental for establishing effective prevention measures.
This article examines the connection between Indigenous women's bodies, their relationship to land and resistance to resource extraction in the Isthmus of Tehuantepec, Mexico. First, I explore the ...processes and practices through which natural resource extraction is expanded into the Global South to demonstrate that Indigenous lands are produced as wastelands that only acquire value through settler states' imposition of land uses and ownership. Second, I show how Indigenous relations to land are simultaneously central to Indigenous struggles against territorial dispossession and Indigenous women's struggles against gendered violence. Operationalising the concept of 'body land', I illustrate how relationships to territory are constituted and fragmented over time, shaping Indigenous women's embodied experiences and transformational political capacities.
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