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1.
Mater Horiz ; 11(10): 2388-2396, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38441222

ABSTRACT

Magnetoelectric multiferroics, either single-phase or composites comprising ferroelectric/ferromagnetic coupled films, are promising candidates for energy efficient memory computing. However, most of the multiferroic magnetoelectric systems studied so far are based on materials that are not compatible with industrial processes. Doped hafnia is emerging as one of the few CMOS-compatible ferroelectric materials. Thus, it is highly relevant to study the integration of ferroelectric hafnia into multiferroic systems. In particular, ferroelectricity in hafnia, and the eventual magnetoelectric coupling when ferromagnetic layers are grown atop of it, are very much dependent on quality of interfaces. Since magnetic metals frequently exhibit noticeable reactivity when grown onto oxides, it is expected that ferroelectricity and magnetoelectricity might be reduced in multiferroic hafnia-based structures. In this article, we present excellent ferroelectric endurance and retention in epitaxial Hf0.5Zr0.5O2 films grown on buffered silicon using Co as the top electrode. The crucial influence of a thin Pt capping layer grown on top of Co on the ferroelectric functional characteristics is revealed by contrasting the utilization of Pt-capped Co, non-capped Co and Pt. Magnetic control of the imprint electric field (up to 40% modulation) is achieved in Pt-capped Co/Hf0.5Zr0.5O2 structures, although this does not lead to appreciable tuning of the ferroelectric polarization, as a result of its high stability. Computation of piezoelectric and flexoelectric strain-mediated mechanisms of the observed magnetoelectric coupling reveal that flexoelectric contributions are likely to be at the origin of the large imprint electric field variation.

2.
Mater Horiz ; 11(10): 2355-2371, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38477152

ABSTRACT

Ferroelectric memory devices such as ferroelectric memristors, ferroelectric tunnel junctions, and field-effect transistors are considered among the most promising candidates for neuromorphic computing devices. The promise arises from their defect-independent switching mechanism, low energy consumption and high power efficiency, and important properties being aimed for are reliable switching at high speed, excellent endurance, retention, and compatibility with complementary metal-oxide-semiconductor (CMOS) technology. Binary or doped binary materials have emerged over conventional complex-composition ferroelectrics as an optimum solution, particularly in terms of CMOS compatibility. The current state-of-the-art route to achieving superlative ferroelectric performance of binary oxides is to induce ferroelectricity at the nanoscale, e.g., in ultra-thin films of doped HfO2, ZrO2, Zn1-xMgxO, Al-xScxN, and Bi1-xSmxO3. This short review article focuses on the materials science of emerging new ferroelectric materials, including their different properties such as remanent polarization, coercive field, endurance, etc. The potential of these materials is discussed for neuromorphic applications.

4.
Cells ; 13(5)2024 Mar 03.
Article in English | MEDLINE | ID: mdl-38474410

ABSTRACT

Dendritic cells (DCs) capture pathogens and process antigens, playing a crucial role in activating naïve T cells, bridging the gap between innate and acquired immunity. However, little is known about DC activation when facing Leishmania parasites. Thus, this study investigates in vitro activity of canine peripheral blood-derived DCs (moDCs) exposed to L. infantum and L. amazonensis parasites and their extracellular vesicles (EVs). L. infantum increased toll-like receptor 4 gene expression in synergy with nuclear factor κB activation and the generation of pro-inflammatory cytokines. This parasite also induced the expression of class II molecules of major histocompatibility complex (MHC) and upregulated co-stimulatory molecule CD86, which, together with the release of chemokine CXCL16, can attract and help in T lymphocyte activation. In contrast, L. amazonensis induced moDCs to generate a mix of pro- and anti-inflammatory cytokines, indicating that this parasite can establish a different immune relationship with DCs. EVs promoted moDCs to express class I MHC associated with the upregulation of co-stimulatory molecules and the release of CXCL16, suggesting that EVs can modulate moDCs to attract cytotoxic CD8+ T cells. Thus, these parasites and their EVs can shape DC activation. A detailed understanding of DC activation may open new avenues for the development of advanced leishmaniasis control strategies.


Subject(s)
Leishmania , Animals , Dogs , CD8-Positive T-Lymphocytes , Dendritic Cells , Adjuvants, Immunologic/metabolism , Cytokines/metabolism , Lymphocyte Activation
5.
J Equine Vet Sci ; 132: 104976, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38056727

ABSTRACT

Horse pythiosis is considered an endemic disease in the Brazilian Pantanal region, causing devastating health and economic losses. This study aimed to enhance the understanding of pythiosis epidemiology, map the distribution of horse body lesions, and investigate the correlation between these lesions and warm body surface areas, potentially implicating hematophagous vectors in the disease's transmission. A prospective study was conducted on equids in the Pantanal Mato-grossense and adjacent areas from 2012 to 2022, with 112 horses and three mules diagnosed with pythiosis. Clinical and epidemiological data, lesions' photographic records, and healthy equids' thermal imaging were collected. Most pythiosis cases occurred between January and March, correlating with regional flood cycles. Most lesions were found on limbs and the ventral abdomen, with dark-colored horses exhibiting a higher frequency of lesions. Interestingly, the thermal mapping revealed that warm areas on a healthy horse's body overlapped significantly with lesion distribution - blood-sucking insects also prefer these areas. The results suggest that pythiosis lesions in horses correlate with warmer areas of the animal body, reinforcing the hypothesis of vector involvement in disease transmission. This study underscores the need for further observational research to fully understand the complex epidemiological dynamics of pythiosis in horses.


Subject(s)
Horse Diseases , Parasites , Pythiosis , Horses , Animals , Horse Diseases/epidemiology , Horse Diseases/pathology , Pythiosis/epidemiology , Pythiosis/pathology , Brazil/epidemiology , Prospective Studies
6.
Mater Horiz ; 11(3): 803-812, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38010915

ABSTRACT

In this work, we demonstrate, for the first time, that coupling together the pyroelectric effect, the photovoltaic effect and the plasmonic effect is a novel method to significantly enhance the performance of self-powered photodetectors in the visible region. Photodetectors based on tri-layered heterojunction of n-Si/p-SnO/n-ZnO through the inclusion of silver (Ag) nanoparticles (NPs) at the SnO/ZnO interface were fabricated. The photo-response of the device, with excitation from a chopped 650 nm wavelength laser, was carefully investigated, and it was shown that the photodetector performance is enhanced the most with the inclusion of spheroidal Ag NPs with ∼70 nm diameter. The Al/Si/SnO/Ag NPs/ZnO/ITO device exhibited an optimum responsivity, detectivity and sensitivity of 210.2 mA W-1, 5.47 × 109 Jones and 15.0 × 104, respectively, together with a rise and fall time of 2.3 and 51.3 µs, respectively, at a laser power density of 317 mW cm-2 and at a chopper frequency of 10 Hz. The present photodetectors are more than twice as responsive as the current best-performing ZnO-based pyro-phototronic photodetectors and they also exhibit other competitive features, such as detectivity, and fall and rise times. Therefore, by exploiting the plasmonic effect of the Ag NPs together with the pyroelectric effect in a ZnO film, and the photovoltaic effect at a Si/SnO junction, all in a single device, photodetectors were developed with state-of-the-art performance for the visible region.

7.
BMJ Case Rep ; 16(12)2023 Dec 23.
Article in English | MEDLINE | ID: mdl-38142058

ABSTRACT

A man in his 60s presented to the emergency department with generalised abdominal pain and distention associated with the inability to pass stool or gas. The patient had undergone a laparoscopic partial right nephrectomy due to renal cell carcinoma a year ago. The workup diagnosis suggested an incarcerated incisional hernia. Surgical treatment was proposed. Intraoperatively, we found an ileocecal appendix with a macroscopically gangrenous appearance inside the hernia sac. An appendectomy was performed, and the hernia defect was closed using a tension repair. Amyand's hernia, a rare condition, is classically described as an inguinal hernia containing the appendix, but it can also refer to an incisional hernia containing the appendix. Amyand's hernia classification depends on the localisation of the hernia sac and its contents, including the presence or absence of appendix inflammation.This case report described a patient with Amyand's hernia, which was diagnosed intraoperatively. The treatment was also discussed including open appendectomy and primary repair of the defect using a tension repair approach.


Subject(s)
Appendicitis , Appendix , Hernia, Inguinal , Incisional Hernia , Male , Humans , Appendicitis/complications , Appendicitis/surgery , Appendicitis/diagnosis , Incisional Hernia/complications , Appendix/surgery , Appendix/pathology , Appendectomy , Hernia, Inguinal/complications , Hernia, Inguinal/diagnosis , Hernia, Inguinal/surgery
8.
Plants (Basel) ; 12(20)2023 Oct 11.
Article in English | MEDLINE | ID: mdl-37896000

ABSTRACT

Rice is one of the most important crops in the world, and its production is severely affected by the rice blast disease caused by the fungus Magnaporthe oryzae. Several major blast resistance genes and QTLs associated with blast resistance have been described and mostly identified in indica rice varieties. In this work, we report the obtention of a blast-resistant rice breeding line derived from crosses between the resistant indica variety CT13432 and the japonica elite cultivar JSendra (highly susceptible to blast). The breeding line, named COPSEMAR9, was found to exhibit resistance to leaf blast and panicle blast, as demonstrated by disease assays under controlled and field conditions. Furthermore, a high-quality genome sequence of the blast-resistant breeding line was obtained using a strategy that combines short-read sequencing (Illumina sequencing) and long-read sequencing (Pacbio sequencing). The use of a whole-genome approach allowed the fine mapping of DNA regions of indica and japonica origin present in the COPSEMAR9 genome and the identification of parental gene regions potentially contributing to blast resistance in the breeding line. Rice blast resistance genes (including Pi33 derived from the resistant parent) and defense-related genes in the genome of COPSEMAR9 were identified. Whole-genome analyses also revealed the presence of microRNAs (miRNAs) with a known function in the rice response to M. oryzae infection in COPSEMAR9, which might also contribute to its phenotype of blast resistance. From this study, the genomic information and analysis methods provide valuable knowledge that will be useful in breeding programs for blast resistance in japonica rice cultivars.

9.
Adv Sci (Weinh) ; 10(15): e2207390, 2023 May.
Article in English | MEDLINE | ID: mdl-36950722

ABSTRACT

A new approach for the stabilization of the ferroelectric orthorhombic ZrO2 films is demonstrated through nanosecond laser annealing (NLA) of as-deposited Si/SiOx /W(14 nm)/ZrO2 (8 nm)/W(22 nm), grown by ion beam sputtering at low temperatures. The NLA process optimization is guided by COMSOL multiphysics simulations. The films annealed under the optimized conditions reveal the presence of the orthorhombic phase, as confirmed by X-ray diffraction, electron backscatter diffraction, and transmission electron microscopy. Macroscopic polarization-electric field hysteresis loops show ferroelectric behavior, with saturation polarization of 12.8 µC cm-2 , remnant polarization of 12.7 µC cm-2 and coercive field of 1.2 MV cm-1 . The films exhibit a wake-up effect that is attributed to the migration of point defects, such as oxygen vacancies, and/or a transition from nonferroelectric (monoclinic and tetragonal phase) to the ferroelectric orthorhombic phase. The capacitors demonstrate a stable polarization with an endurance of 6.0 × 105 cycles, demonstrating the potential of the NLA process for the fabrication of ferroelectric memory devices with high polarization, low coercive field, and high cycling stability.

10.
Materials (Basel) ; 16(4)2023 Feb 05.
Article in English | MEDLINE | ID: mdl-36836974

ABSTRACT

Silver-ceramic nanocomposite coatings, such as TiN:Ag, are among the most interesting solutions to improve the machining and cutting process of hard-to-cut Ti alloys, since they combine the TiN matrix hardness with the lubricating and protective action of Ag nanoparticles. Therefore, it is important to understand how, when present, Ag distributes at the tool-workpiece interface and how it affects the tribolayer formation and the tool wear. Molecular dynamics simulation results, obtained using a MEAM-based force field, are presented here for the cutting process of a Ti workpiece with a TiN tool, with and without the presence of Ag at the interface, for different cutting speeds. Ag is shown to form a thin protective layer at the workpiece-tool interface that prevents a direct contact between the parts and greatly reduces the tool degradation. Our simulations confirm the importance of Ag in self-lubricating nanocomposite coatings to realize the machining of otherwise hard-to-cut materials.

11.
Materials (Basel) ; 16(3)2023 Feb 02.
Article in English | MEDLINE | ID: mdl-36770281

ABSTRACT

Zn:ZnO nanostructures have been studied extensively due to their potential use in many applications, such as oxygen scavengers for food packaging applications. Under atmospheric conditions, ZnO grows on the surface of Zn via an oxidation process. The mechanisms governing Zn oxidation are still not fully understood, with classical oxidation models, such as the Cabrera Mott, underestimating the oxide thickness of Zn:ZnO core-shell structures. In this work, Ab initio DFT calculations were performed to assess the adsorption properties of oxygen molecules on Zn:ZnO heterostructures to help elucidate the mechanisms involved in the growth of a ZnO film on a Zn substrate. Results suggest that the charge transfer mechanism from the Zn:ZnO heterostructures to the adsorbed oxygen layer can be promoted by two different processes: the electronic doping of ZnO due to the formation of the Zn:ZnO interface and the excess surface charge due to the presence of dangling bonds on the as cleaved ZnO.

12.
Motrivivência (Florianópolis) ; 35(66): 1-21, 2023.
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1451928

ABSTRACT

Este artigo teve como objetivo analisar a configuração atual do Fundo de Apoio ao Esporte do Distrito Federal - FAE, a partir de uma metodologia crítica de análise do financiamento de políticas sociais. Os resultados demonstraram dependência em relação à fonte de recursos advindos das loterias federais, baixo percentual de execução financeira, predominância de financiamento de projetos focalizados no esporte de alto rendimento e descumprimento da legislação vigente na destinação dos gastos. Como conclusão, entende-se que o FAE pouco tem contribuído para a garantia do direito ao esporte no Distrito Federal.


This article aimed to analyze the current configuration of the Sports Support Fund of the Federal District - FAE, from a critical methodology for analyzing the financing of social policies. The results showed dependence on the source of resources from federal lotteries, low percentage of financial execution, the predominance of financing of projects focused on high-performance sports, and noncompliance with current legislation in the allocation of expenditures. In conclusion, it is understood that the FAE has contributed little to guarantee the right to sport in the Federal District


Este artículo tuvo como objetivo analizar la configuración actual del Fondo de Apoyo al Deporte del Distrito Federal - FAE, a partir de una metodología crítica para analizar el financiamiento de las políticas sociales. Los resultados mostraron dependencia de la fuente de recursos de las loterías federales, bajo porcentaje de ejecución financiera, predominio del financiamiento de proyectos enfocados en deportes de alto rendimiento e incumplimiento de la legislación vigente en la asignación de gastos. En conclusión, se entiende que la FAE ha contribuido poco a la garantía del derecho al deporte en el Distrito Federal.

13.
Heliyon ; 8(12): e11920, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36478844

ABSTRACT

This paper proposes an open-source tool for a fast and precise calculation of the inductance of planar coils in the presence of conductive targets. This tool, based on Grover equations, is versatile to any coil and target geometries. The performance of this tool has been validated by comparing the analytical results with experimental data and Finite Element Model (FEM) simulations. When compared with the experimental measurements, the developed analytical model and the FEM simulation retrieved similar results, with differences below 4%. The proposed tool, in addition to requiring less computing resources, is significantly faster than FEM simulations. This shows the effectiveness of the proposed approach for the analytical calculation of the inductance of planar coils in the presence of conductive plates. It combines accuracy, versatility, speed, and no need for high computational resources.

14.
J Vasc Access ; : 11297298221124742, 2022 Dec 14.
Article in English | MEDLINE | ID: mdl-36517935

ABSTRACT

Partial anomalous pulmonary vein drainage is a rare congenital defect, where the pulmonary vein drains into a systemic vein instead of draining into the left atrium. We present a case of a 63-year-old woman on hemodialysis who was found to have a right pulmonary vein with anomalous drainage to the superior vena cava after mal-positioning of a dialysis catheter, which demonstrated unexpected blood results from the different lumina of the catheter. Multiple imaging techniques were used to deal with this rare clinical situation. This is the first case reporting a mal-positioning of a left-side internal jugular vein tunneled catheter into a right-side pulmonary vein.

15.
Molecules ; 27(22)2022 Nov 14.
Article in English | MEDLINE | ID: mdl-36431939

ABSTRACT

The growing human population, together with the inefficient use of natural resources, has been dramatically increasing the production of food waste, which poses serious economic, environmental, and social problems. Being so, it is necessary to increase the efficiency of food consumption so as to reduce its waste and to convert the remaining residues into societal benefits. Since this biowaste is rich in polyphenols and vitamins, it could become the feedstock for the production of important value-added compounds for the pharmaceutical (e.g., food supplements) and cosmetic (e.g., creams and shampoos) industries. In this work, partition studies of one polyphenol (epicatechin) and two B-complex vitamins (cyanocobalamin and nicotinic acid) were performed in biodegradable Aqueous Two-Phase Systems (ATPS) based on ethyl lactate and on organic salts (disodium tartrate, tripotassium citrate, and trisodium citrate) at 298.15 K and 0.1 MPa. The largest partition coefficient (K) and extraction efficiency (E) were obtained for vitamin B12 (K=78.56, E=97.5%) for the longest tie line TLL=77.66% in the ATPS {ethyl lactate (1) + tripotassium citrate (2) + water (3)}. All the extractions were obtained with low biomolecule mass losses in quantification (<5%) and after a thorough study of pH influence in the UV−Vis absorbance spectra.


Subject(s)
Refuse Disposal , Vitamins , Humans , Polyphenols , Vitamin A , Vitamin K , Vitamin B 12 , Water , Potassium Citrate
16.
Polymers (Basel) ; 14(21)2022 Oct 26.
Article in English | MEDLINE | ID: mdl-36365517

ABSTRACT

Manipulation of nanoscale objects using molecular self-assembly is a potent tool to achieve large scale nanopatterning with small effort. Coordination polymers of bis-salphen compounds based on zinc have demonstrated their ability to align carbon nanotubes into micro-scale networks with an unusual "rings-and-rods" pattern. This paper investigates how the compounds interact with pristine and functionalized graphene using density functional theory calculations and molecular dynamic simulations. Using the free energy perturbation method we will show how the addition of phenyl side groups to the core compound and functionalization of graphene affect the stability, mobility and conformation adopted by a dimer of bis-(Zn)salphen compound adsorbed on graphene surface and what it can reveal about the arrangement of chains of bis-(Zn)salphen polymer around carbon nanotubes during the self-assembly of microscale networks.

17.
Front Surg ; 9: 888546, 2022.
Article in English | MEDLINE | ID: mdl-36211258

ABSTRACT

The Covid-19 pandemic has caused major changes in many sectors of society worldwide. The issue of medical education stands out since it had to adapt to the rules of social isolation, ensuing discussions about the computerization of teaching methodology, particularly in neuroanatomy. In particular, the latter showed satisfactory adaptability to new technologies and highly promising learning results. During this review, we aim to evaluate the current state of neuroanatomy teaching and evaluate the possibilities of incorporating technology into teaching-learning of human anatomy in a post-pandemic world.

18.
Polymers (Basel) ; 14(9)2022 Apr 19.
Article in English | MEDLINE | ID: mdl-35566811

ABSTRACT

Aliphatic isocyanates and polyisocyanates are central molecules in the fabrication of polyurethanes, coatings, and adhesives and, due to their excellent mechanical and stability properties, are continuously investigated in advanced applications; however, despite the growing interest in isocyanate-based systems, atomistic simulations on them have been limited by the lack of accurate parametrizations for these molecular species. In this review, we will first provide an overview of current research on isocyanate systems to highlight their most promising applications, especially in fields far from their typical usage, and to justify the need for further modeling works. Next, we will discuss the state of their modeling, from first-principle studies to atomistic molecular dynamics simulations and coarse-grained approaches, highlighting the recent advances in atomistic modeling. Finally, the most promising lines of research in the modeling of isocyanates are discussed in light of the possibilities opened by novel approaches, such as machine learning.

19.
Methods Mol Biol ; 2494: 299-312, 2022.
Article in English | MEDLINE | ID: mdl-35467216

ABSTRACT

The damage that herbivores inflict on plants is a key component of their interaction. Several methods have been proposed to quantify the damage caused by chewing insects, but such methods are not very successful when the damage is inflicted by a cell-sucking organism. Here, we present a protocol that allows a non-destructive quantification of the damage inflicted by cell-sucking arthropods, robustly filtering out leaf vascular structures that might be mistakenly classified as damage in many plant species. The protocol is set for the laboratory environment and uses Fiji and ilastik, two free software packages.


Subject(s)
Arthropods , Herbivory , Animals , Insecta , Plant Leaves , Plants
20.
ACS Biomater Sci Eng ; 8(1): 314-327, 2022 01 10.
Article in English | MEDLINE | ID: mdl-34963288

ABSTRACT

This paper presents the development of advanced Ti implants with enhanced antibacterial activity. The implants were engineered using additive manufacturing three-dimensional (3D) printing technology followed by surface modification with electrochemical anodization and hydrothermal etching, to create unique hierarchical micro/nanosurface topographies of microspheres covered with sharp nanopillars that can mechanically kill bacteria in contact with the surface. To achieve enhanced antibacterial performance, fabricated Ti implant models were loaded with gallium nitrate as an antibacterial agent. The antibacterial efficacy of the fabricated substrates with the combined action of sharp nanopillars and locally releasing gallium ions (Ga3+) was evaluated toward Staphylococcus aureus and Pseudomonas aeruginosa. Results confirm the significant antibacterial performance of Ga3+-loaded substrates with a 100% eradication of bacteria. The nanopillars significantly reduced bacterial attachment and prevented biofilm formation while also killing any bacteria remaining on the surface. Furthermore, 3D-printed surfaces with microspheres of diameter 5-30 µm and interspaces of 12-35 µm favored the attachment of osteoblast-like MG-63 cells, as confirmed via the assessment of their attachment, proliferation, and viability. This study provides important progress toward engineering of next-generation 3D-printed implants, that combine surface chemistry and structure to achieve a highly efficacious antibacterial surface with dual cytocompatibility to overcome the limitations of conventional Ti implants.


Subject(s)
Gallium , Titanium , Anti-Bacterial Agents/pharmacology , Printing, Three-Dimensional , Surface Properties
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