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In this work we present a study we present a comparative study of lithium insertion in several compounds of general formula MMoO4 (M = Zn, Ni, Mn, Cu, Co) and in Al2(MoO4)3, prepared by solid state reaction (RES) and by solution and precipitation (RS). The electrochemical study showed no difference on the performance of the compounds prepared by these two methods and with a similar degree of crystallinity. However, those compounds prepared by RS and fired to intermediate temperatures, incorporated a larger amount of lithium atoms although in all cases an irreversible transformation of the pristine materials was observed with a complete loss of crystallinity after the initial discharge. The amount of lithium atoms incorporated was large although the insertion is not reversible and most of them are not extracted afeter completing a charge-discharge cycle.En este trabajo se presenta un estudio de la inserción electroquímica de litio en molibdatos de fórmula general MMoO4 (M = Zn, Ni, Mn, Cu y Co) y en Al2(MoO4)3 preparados por reacción de estado sólido (RES) y por reacción en solución (RS). El estudio electroquímico mostró que en general, no existen diferencias fundamentales en el comportamiento de los molibdatos sintetizados por uno u otro método y con semejante grado de cristalinidad. Sin embargo, los compuestos preparados por RS y calcinados a temperaturas intermedias incorporaron una mayor cantidad de litio que los obtenidos por RES aunque en todos los casos se observó una transformación irreversible de los compuestos originales con pérdida casi completa de la cristalinidad durante la primera descarga de la celda. La cantidad de átomos de litio incorporados en estos compuestos fue muy elevada (Li/ΣM ≈ 4) aunque de forma irreversible.

El análisis del mercado de factores no es un tema usual en los cursos convencionales de microeconomía y cuando se aborda no se explican las motivaciones de las firmas al momento de tomar su decisión de compra de insumos. En contraste, se presentan amplias discusiones dirigidas a interpretar mecanismos de elección de las empresas en la producción y comercialización de bienes, en contextos oligopólicos y monopólicos. Este trabajo propone una reflexión del problema, a partir de instrumentos similares a los utilizados habitualmente para entender las motivaciones de una firma cuando determina sus decisiones estratégicas en mercados de bienes finales.

The existence of superconductivity (SC) appears to be established in both twisted and nontwisted graphene multilayers. However, whether their building block, single-layer graphene (SLG), can also host SC remains an open question. Earlier theoretical works predicted that SLG could become a chiral d -wave superconductor driven by electronic interactions when doped to its van Hove singularity, but questions such as whether the d -wave SC survives the strong band renormalizations seen in experiments, its robustness against the source of doping, or if it will occur at any reasonable critical temperature ( T c ) have remained difficult to answer, in part due to uncertainties in model parameters. Furthermore, doping of graphene beyond its van Hove singularity remained experimentally challenging and was not demonstrated until recently. In this study, we n dope SLG past the van Hove singularity by employing Tb intercalation and derive structural models from angle-resolved photoemission spectroscopy measurements. We adopt a reliable numerical framework based on a random-phase approximation technique to investigate the emergence of unconventional SC in the heavily doped monolayer. We predict that robust d + id topological SC could arise in SLG doped by Tb, with a T c up to 600 mK. We also employ first-principles calculations to investigate the possibility of realizing d -wave SC with other dopants, such as Li or Cs. We find that dopants that change the lattice symmetry of SLG are detrimental to the d -wave state. The stability of the d -wave SC predicted here in Tb-doped SLG could provide a valuable insight for guiding future experimental efforts aimed at exploring topological superconductivity in monolayer graphene.

Neutrophils orchestrate a coordinated attack on bacteria, combining phagocytosis with a potent cocktail of oxidants, including the highly toxic hypochlorous acid (HOCl), renowned for its deleterious effects on proteins. Here, we examined the occurrence of lipid N-chloramines in vivo, their biological activity, and their neutralization. Using a chemical probe for N-chloramines, we demonstrate their formation in the membranes of bacteria and monocytic cells exposed to physiologically relevant concentrations of HOCl. N-chlorinated model membranes composed of phosphatidylethanolamine, the major membrane lipid in Escherichia coli and an important component of eukaryotic membranes, exhibited oxidative activity towards the redox-sensitive protein roGFP2, suggesting a role for lipid N-chloramines in protein oxidation. Conversely, glutathione a cellular antioxidant neutralized lipid N-chloramines by removing the chlorine moiety. In line with that, N-chloramine stability was drastically decreased in bacterial cells compared to model membranes. We propose that lipid N-chloramines, like protein N-chloramines, are involved in inflammation and accelerate the host immune response., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

P4-ATPases in complex with Cdc50 subunits are lipid flippases that couple ATP hydrolysis with lipid transport to the cytoplasmic leaflet of membranes to create lipid asymmetry. Such vectorial transport has been shown to contribute to vesicle formation in the late secretory pathway. Some flippases are regulated by autoinhibitory regions that can be destabilized by protein kinase-mediated phosphorylation and possibly by binding of cytosolic proteins. In addition, the binding of lipids to flippases may also induce conformational changes required for the activity of these transporters. Here, we address the role of phosphatidylinositol-4-phosphate (PI4P) and the terminal autoinhibitory tails on the lipid flipping activity of the yeast lipid flippase Drs2-Cdc50. By functionally reconstituting the full-length and truncated forms of Drs2 in a 1:1 complex with the Cdc50 subunit, we provide compelling evidence that lipid flippase activity is exclusively detected for the truncated Drs2 variant and is dependent on the presence of the phosphoinositide PI4P. These findings highlight the critical role of phosphoinositides as lipid co-factors in the regulation of lipid transport by the Drs2-Cdc50 flippase., (© 2023 The Authors. Protein Science published by Wiley Periodicals LLC on behalf of The Protein Society.)

Purpose: To investigate the effect of a voice and communication training program for oral presentations on higher education students., Methods: The proposed training program was based on the areas of social skills, voice projection techniques, and neurolinguistic programming. Thirty-eight students participated in the training with active learning methodologies at the university. Before and after the intervention, the participants recorded a short oral presentation on a topic of their choice. The recording was presented to the other participants and to a panel formed by three examiners (two articulation therapists and a psychologist), who evaluated the oral presentation performances. Moreover, each individual self-assessed their communication. The evaluation criteria covered the linguistic aspects, formal and non-formal, verbal and non-verbal communication, planning, and elaboration of the presentation., Results: All participants improved their performance in oral presentations regarding verbal and para-verbal aspects, ability to keep the audience, emotional control, planning, objective, content, approach, organization, visual resource, form of presentation, language, and general elements (general presentation)., Conclusion: The proposed training program is effective in improving the performance of university students in oral presentations.

This is an update of a previous review (Naumis et al 2017 Rep. Prog. Phys. 80 096501). Experimental and theoretical advances for straining graphene and other metallic, insulating, ferroelectric, ferroelastic, ferromagnetic and multiferroic 2D materials were considered. We surveyed (i) methods to induce valley and sublattice polarisation ( P ) in graphene, (ii) time-dependent strain and its impact on graphene's electronic properties, (iii) the role of local and global strain on superconductivity and other highly correlated and/or topological phases of graphene, (iv) inducing polarisation P on hexagonal boron nitride monolayers via strain, (v) modifying the optoelectronic properties of transition metal dichalcogenide monolayers through strain, (vi) ferroic 2D materials with intrinsic elastic ( σ ), electric ( P ) and magnetic ( M ) polarisation under strain, as well as incipient 2D multiferroics and (vii) moiré bilayers exhibiting flat electronic bands and exotic quantum phase diagrams, and other bilayer or few-layer systems exhibiting ferroic orders tunable by rotations and shear strain. The update features the experimental realisations of a tunable two-dimensional Quantum Spin Hall effect in germanene, of elemental 2D ferroelectric bismuth, and 2D multiferroic NiI 2 . The document was structured for a discussion of effects taking place in monolayers first, followed by discussions concerning bilayers and few-layers, and it represents an up-to-date overview of exciting and newest developments on the fast-paced field of 2D materials., (Creative Commons Attribution license.)

Many natural products have been acquired from plants for their helpful properties. Medicinal plants are used for treating a variety of pathologies or symptoms. The axes of many pathological processes are inflammation, oxidative stress, and senescence. This work is focused on identifying Mexican medicinal plants with potential anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence effects through network analysis and chemoinformatic screening of their phytochemicals. We used computational methods to analyze drug-like phytochemicals in Mexican medicinal plants, multi-target compounds, and signaling pathways related to anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence mechanisms. A total of 1373 phytochemicals are found in 1025 Mexican medicinal plants, and 148 compounds showed no harmful functionalities. These compounds displayed comparable structures with reference molecules. Based on their capacity to interact with pharmacological targets, three clusters of Mexican medicinal plants have been established. Curatella americana , Ximenia americana , Malvastrum coromandelianum , and Manilkara zapota all have anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence effects. Plumeria rubra , Lonchocarpus yucatanensis , and Salvia polystachya contained phytochemicals with anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence reported activity. Lonchocarpus guatemalensis , Vallesia glabra , Erythrina oaxacana , and Erythrina sousae have drug-like phytochemicals with potential anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence effects. Between the drug-like phytochemicals, lonchocarpin, vallesine, and erysotrine exhibit potential anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence effects. For the first time, we conducted an initial virtual screening of selected Mexican medicinal plants, which was subsequently confirmed in vivo, evaluating the anti-inflammatory activity of Lonchocarpus guatemalensis Benth in mice.

Purpose: Compare the psychoeducational profiles of children with verbal and non-verbal Autism Spectrum Disorder (ASD)., Methods: Cross-sectional study conducted with a sample of 30 children with a medical diagnosis of ASD (15 verbal and 15 non-verbal) aged 2-9 years. The Psychoeducational Profile-Revised (PEP-R) scale was applied to assess the children's development. The data were analyzed quantitatively and comparatively. Analysis of covariance (ANCOVA) was performed to evaluate the compatibility between the groups regarding the scores obtained in each PEP-R area, with chronological age as the covariate, and Student's t-Test was used for the independent samples (p≤0.001)., Results: The scores in the different areas of the PEP-R were higher in the verbal group, with associations between language development and cognitive and social adaptive skills in the studied sample. Comparison between the groups showed a lower profile of the non-verbal group, with statistically significant differences in the areas of imitation, perception, gross and fine motor coordination, eye-hand coordination, cognitive performance, and verbal performance., Conclusion: The goal of comparing the psychoeducational profiles of verbal and non-verbal ASD children was reached, and statistically significant differences were observed. The children with non-verbal ASD presented a lower psychoeducational profile compared with that of verbal ASD children. Further studies with larger samples, delimited age groups, and more specific tests in each developmental area are suggested.

Lipid transporters play a crucial role in supporting essential cellular processes such as organelle assembly, vesicular trafficking, and lipid homeostasis by driving lipid transport across membranes. Cryo-electron microscopy has recently resolved the structures of several ATP-dependent lipid transporters, but functional characterization remains a major challenge. Although studies of detergent-purified proteins have advanced our understanding of these transporters, in vitro evidence for lipid transport is still limited to a few ATP-dependent lipid transporters. Reconstitution into model membranes, such as liposomes, is a suitable approach to study lipid transporters in vitro and to investigate their key molecular features. In this review, we discuss the current approaches for reconstituting ATP-driven lipid transporters into large liposomes and common techniques used to study lipid transport in proteoliposomes. We also highlight the existing knowledge on the regulatory mechanisms that modulate the activity of lipid transporters, and finally, we address the limitations of the current approaches and future perspectives in this field., (© 2023 The Author(s).)

Eukaryotic cells use a series of membrane transporters to control the movement of lipids across their plasma membrane. Several tools and techniques have been developed to analyze the activity of these transporters in the plasma membrane of mammalian cells. Among them, assays based on fluorescence microscopy in combination with fluorescent lipid probes are particularly suitable, allowing visualization of lipid internalization in living cells. Here, we provide a step-by-step protocol for mammalian cell culture, lipid probe preparation, cell labeling, and confocal imaging to monitor lipid internalization by lipid flippases at the plasma membrane based on lipid probes carrying a fluorophore at a short-chain fatty acid. The protocol allows studying a wide range of mammalian cell lines, to test the impact of gene knockouts on lipid internalization at the plasma membrane and changes in lipid uptake during cell differentiation. Key features Visualization and quantification of lipid internalization by lipid flippases at the plasma membrane based on confocal microscopy. Assay is performed on living adherent mammalian cells in culture. The protocol can be easily modified to a wide variety of mammalian cell lines., Competing Interests: Competing interestsThe authors declare that no competing interests exist., (©Copyright : © 2023 The Authors; This is an open access article under the CC BY-NC license.)

Background: Pediatric inflammatory multisystem syndrome (PIMS) is a complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children that resembles Kawasaki syndrome and places them at high risk of cardiorespiratory instability and/or cardiac damage. This study aims to describe the clinical presentation and outcomes of patients with PIMS in Mexico City., Methods: This was an observational study of children hospitalized for PIMS based on the Centers for Disease Control and Prevention case definition criteria, in a single tertiary care pediatric center in Mexico City between May 1, 2020, and September 30, 2021. Demographic characteristics, epidemiological data, medical history, laboratory tests, cardiologic evaluations, treatment, and clinical outcomes were analyzed., Results: Seventy-five cases fulfilled the case definition criteria for PIMS [median age: 10.9 years, Interquartile range (IQR): 5.6-15.6]. Fifteen (20%) patients had a severe underlying disease, 48 (64%) were admitted to the intensive care unit, 33 (44%) required invasive mechanical ventilation and 39 (52%) received vasopressor support. The patients were clustered through latent class analysis based on identified symptoms: Cluster 1 had rash or gastrointestinal symptoms ( n = 60) and cluster 2 were those with predominantly respiratory manifestations ( n = 15). Two patients (2.7%) died, and both had severe underlying conditions. Five patients (6.7%), all from cluster 1, developed coronary aneurysms., Conclusion: There were a high proportion of patients with severe respiratory involvement and positive RT-PCR SARS-CoV-2 and very few cases of coronary aneurysms in our study which suggests that a high proportion of the children had severe acute COVID-19. The clinical manifestations and outcomes are comparable to previously reported international studies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Gil Guevara, Marroquín Yáñez, Jiménez-Juárez, Olivar Lopez, Chávez Lopez, Sienra Monge, Jamaica Balderas, Martínez Herrera, Domínguez-Barrera, Erdmenger Orellana, Márquez González, Klünder-Klünder, Nieto Zermeño, Villa Guillen, González García and Castilla-Peon.)

P4-ATPases flip lipids from the exoplasmic to the cytosolic leaflet, thus maintaining lipid asymmetry in eukaryotic cell membranes. Mutations in several human P4-ATPase genes are associated with severe diseases, for example in ATP8B1 causing progressive familial intrahepatic cholestasis, a rare inherited disorder progressing toward liver failure. ATP8B1 forms a binary complex with CDC50A and displays a broad specificity to glycerophospholipids, but regulatory mechanisms are unknown. Here, we report functional studies and the cryo-EM structure of the human lipid flippase ATP8B1-CDC50A at 3.1 Å resolution. We find that ATP8B1 is autoinhibited by its N- and C-terminal tails, which form extensive interactions with the catalytic sites and flexible domain interfaces. Consistently, ATP hydrolysis is unleashed by truncation of the C-terminus, but also requires phosphoinositides, most markedly phosphatidylinositol-3,4,5-phosphate (PI(3,4,5)P 3 ), and removal of both N- and C-termini results in full activation. Restored inhibition of ATP8B1 truncation constructs with a synthetic peptide mimicking the C-terminal segment further suggests molecular communication between N- and C-termini in the autoinhibition and demonstrates that the regulatory mechanism can be interfered with by exogenous compounds. A recurring (G/A)(Y/F)AFS motif of the C-terminal segment suggests that this mechanism is employed widely across P4-ATPase lipid flippases in plasma membrane and endomembranes., Competing Interests: TD, SH, ML, ML, CS, KS, CJ, JL, CM, TP, PN, GL No competing interests declared, (© 2022, Dieudonné et al.)

All eukaryotic cells are equipped with transmembrane lipid transporters, which are key players in membrane lipid asymmetry, vesicular trafficking, and membrane fusion. The link between mutations in these transporters and disease in humans highlights their essential role in cell homeostasis. Yet, many key features of their activities, their substrate specificity, and their regulation remain to be elucidated. Here, we describe an optimized quantitative flow cytometry-based lipid uptake assay utilizing nitrobenzoxadiazolyl (NBD) fluorescent lipids to study lipid internalization in mammalian cell lines, which allows characterizing lipid transporter activities at the plasma membrane. This approach allows for a rapid analysis of large cell populations, thereby greatly reducing sampling variability. The protocol can be applied to study a wide range of mammalian cell lines, to test the impact of gene knockouts on lipid internalization at the plasma membrane, and to uncover the dynamics of lipid transport at the plasma membrane. Graphic abstract: Internalization of NBD-labeled lipids from the plasma membrane of CHO-K1 cells., Competing Interests: Competing interestsThe authors declare that no competing interests exist., (Copyright © 2022 The Authors; exclusive licensee Bio-protocol LLC.)

Nitrous oxide (N 2 O) is a long-lived greenhouse gas that also destroys stratospheric ozone. N 2 O emissions are uncertain and characterized by high spatiotemporal variability, making individual observations difficult to upscale, especially in mixed land use source regions like the San Joaquin Valley (SJV) of California. Here, we calculate spatially integrated N 2 O emission rates using nocturnal and convective boundary-layer budgeting methods. We utilize vertical profile measurements from the NASA DISCOVER-AQ (Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality) campaign, which took place January-February, 2013. For empirical constraints on N 2 O source identity, we analyze N 2 O enhancement ratios with methane, ammonia, carbon dioxide, and carbon monoxide separately in the nocturnal boundary layer, nocturnal residual layer, and convective boundary layer. We find that an established inventory (EDGAR v4.3.2) underestimates N 2 O emissions by at least a factor of 2.5, that wintertime emissions from animal agriculture are important to annual totals, and that there is evidence for higher N 2 O emissions during the daytime than at night.

Chitons are herbivorous invertebrates that use rows of ultrahard magnetite-based teeth connected to a flexible belt (radula) to rasp away algal deposits growing on and within rocky outcrops along coastlines around the world. Each tooth is attached to the radula by an organic structure (stylus) that provides mechanical support during feeding. However, the underlying structures within the stylus, and their subsequent function within the chiton have yet to be investigated. Here, we investigate the macrostructural architecture, the regional material and elemental distribution and subsequent nano-mechanical properties of the stylus from the Northern Pacific dwelling Cryptochiton stelleri. Using a combination of μ-CT imaging, optical and electron microscopy, as well as elemental analysis, we reveal that the stylus is a highly contoured tube, mainly composed of alpha-chitin fibers, with a complex density distribution. Nanoindentation reveals regiospecific and graded mechanical properties that can be correlated with both the elemental composition and material distribution. Finite element modeling shows that the unique macroscale architecture, material distribution and elemental gradients have been optimized to preserve the structural stability of this flexible, yet robust functionally-graded fiber-reinforced composite tube, providing effective function during rasping. Understanding these complex fiber-based structures offers promising blueprints for lightweight, multifunctional and integrated materials., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

What Is Known and Objective: Since 2011, a collaborative territorial network for urgent care has been deployed in Hospital de la Santa Creu i Sant Pau area, which allows direct and early transfer of patients with frailty from the hospital emergency department (ED) to other healthcare settings according to the destination's adequacy. This study aimed to identify factors associated with inappropriate intravenous antibiotic treatment prescribed on referral of patients with frailty based on microbiological culture and analyse the effect of inappropriate prescription on ED reconsultations for any cause 30 days after hospital discharge., Methods: This observational, retrospective study was performed at a tertiary hospital between March 2018 and February 2019 and included 264 patients. A multivariate analysis, including variables with a P-value <.2 in the previous univariate analysis, was conducted. The variables included in the analysis were age, sex, patient comorbidities (COPD, diabetes and chronic kidney disease), antibiotic treatment in the last 30 days and patient referral (nursing home or family home)., Results and Discussion: Multidrug-resistant bacteria were isolated from 85 patients (51.5% of the isolates). In total, 159 patients received carbapenem, of whom 87 (54.7%) had non-drug-resistant bacteria. The antibiotic was considered inappropriate in 33 patients (12.5%) according to an antibiogram. Only 71 (26.8%) patients had a definitive culture on discharge. Moreover, 73 (28.3%) patients were readmitted after 30 days. Patients with an inappropriate antibiotic treatment had more reconsultations within 30 days than those with adequate treatment (59.3% vs 24.5%; P < .001). In a multivariate analysis, an inappropriate prescription was significantly associated with a higher number of reconsultations at 30 days (OR, 3.22 [1.37-7.57])., What Is New and Conclusion: In patients discharged from the ED with intravenous antibiotics, the empirical prescription of an inappropriate drug according to the final culture is a frequent problem and is related to a higher number of reconsultations. This highlights the need to implement early communication strategies with outpatient units to optimize antibiotic therapy once microbiological results are known., (© 2020 John Wiley & Sons Ltd.)

Drought conditions affect ozone air quality, potentially altering multiple terms in the O 3 mass balance equation. Here, we present a multiyear observational analysis using data collected before, during, and after the record-breaking California drought (2011-2015) at the O 3 -polluted locations of Fresno and Bakersfield near the Sierra Nevada foothills. We separately assess drought influences on O 3 chemical production ( PO 3 ) from O 3 concentration. We show that isoprene concentrations, which are a source of O 3 -forming organic reactivity, were relatively insensitive to early drought conditions but decreased by more than 50% during the most severe drought years (2014-2015), with recovery a function of location. We find drought-isoprene effects are temperature-dependent, even after accounting for changes in leaf area, consistent with laboratory studies but not previously observed at landscape scales with atmospheric observations. Drought-driven decreases in organic reactivity are contemporaneous with a change in dominant oxidation mechanism, with PO 3 becoming more NO x -suppressed, leading to a decrease in PO 3 of ∼20%. We infer reductions in atmospheric O 3 loss of ∼15% during the most severe drought period, consistent with past observations of decreases in O 3 uptake by plants. We consider drought-related trends in O 3 variability on synoptic time scales by analyzing statistics of multiday high-O 3 events. We discuss implications for regulating O 3 air pollution in California and other locations under more prevalent drought conditions.