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1.
Hepatology ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739848

RESUMO

BACKGROUND AIMS: A new term, metabolic dysfunction-associated steatotic liver disease(MASLD), has been proposed by a multi-society expert panel. However, it remains unclear whether hepatic steatosis per se in MASLD contributes to an increased risk of mortality in individuals with any cardio-metabolic risk factor(CMRF), which are also significant risk factors for increased mortality. This study aimed to compare all-cause and cause-specific mortality between the 'MASLD/MetALD' and 'no steatotic liver disease(SLD)' groups in individuals with any CMRF. APPROACH AND RESULTS: A population-based cohort study was conducted using 10,750 participants of NHANES III. All-cause and cause-specific(cardiovascular, cancer, diabetes, and liver) mortality risks were compared between the 'MASLD', 'MetALD', and 'no SLD' groups using the Cox proportional hazards model with complex survey design weights, adjusted for confounders. Over 26 years, the 'MASLD' group did not show significantly increased all-cause(adjusted hazard ratio 1.04[95% confidence interval 0.95-1.14], p=0.413), cardiovascular(0.88[0.75-1.04], p=0.139), or cancer(1.06[0.84-1.33], p=0.635) mortality risk compared to the 'no SLD' group in individuals with any CMRF. The MetALD group was associated with increased all-cause(1.41 [1.05-1.89], p=0.022), cancer(2.35[1.33-4.16], p=0.004) and liver(15.04[2.96-76.35], p=0.002) mortality risk compared with the no SLD group. This trend was more pronounced in MetALD group with advanced fibrosis assessed by FIB-4. CONCLUSION: In individuals with CMRF, the presence of steatotic liver disease (MASLD) alone did not increase the risk of mortality, except in cases with more alcohol consumption (MetALD). Therefore controlling metabolic risk factors and reducing alcohol consumption in people with MASLD or MetALD will be crucial steps to improve long-term health outcomes.

2.
Polymers (Basel) ; 16(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38674968

RESUMO

Polymethyl methacrylate (PMMA) is an interesting polymer employed in various applications due to its outstanding properties. However, its electrical and mechanical properties can be further improved by incorporating nanoparticles, and in particular, PMMA nanocomposite with nanoparticles provides various multifunctional properties. This work reports PMMA nanocomposite preparation and structural and optical characterizations incorporating carbon nanotubes (CNTs), TiO2 nanoparticles, and carbon quantum dots (CQDs). CNT/PMMA, TiO2/PMMA, and CQD/PMMA nanocomposite freestanding films were prepared using a simple solution method. Various properties of the prepared composite films were analyzed using scanning electron microscopy, X-ray diffraction, photoluminescence, Fourier transform infrared, and UV-Vis and Raman spectroscopy. Optical parameters and photocatalytic dye degradation for the films are reported, focusing on the properties of the materials. The CNT/PMMA, TiO2/PMMA, and CQD/PMMA films achieved, respectively, good electrical conductivity, photodegradation, and fluorescence compared with other composite films.

3.
Nat Commun ; 15(1): 3381, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643182

RESUMO

The synthesis of sequence-regulated oligosulfates has not yet been established due to the difficulties in precise reactivity control. In this work, we report an example of a multi-directional divergent iterative method to furnish oligosulfates based on a chain homologation approach, in which the fluorosulfate unit is regenerated. The oligosulfate sequences are determined by high resolution mass spectrometry of the hydrolyzed fragments, and polysulfate periodic copolymers are synthesized by using oligomeric bisfluorosulfates in a bi-directional fashion. The synthetic utility of this iterative ligation is demonstrated by preparing crosslinked network polymers as synthetic adhesive materials.

4.
Sci Rep ; 14(1): 8602, 2024 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615106

RESUMO

Although the esophageal stethoscope is used for continuous auscultation during general anesthesia, few studies have investigated phonocardiographic data as a continuous hemodynamic index. In this study, we aimed to induce hemodynamic variations and clarify the relationship between the heart sounds and hemodynamic variables through an experimental animal study. Changes in the cardiac contractility and vascular resistance were induced in anesthetized pigs by administering dobutamine, esmolol, phenylephrine, and nicardipine. In addition, a decrease in cardiac output was induced by restricting the venous return by clamping the inferior vena cava (IVC). The relationship between the hemodynamic changes and changes in the heart sound indices was analyzed. Experimental data from eight pigs were analyzed. The mean values of the correlation coefficients of changes in S1 amplitude (ΔS1amp) with systolic blood pressure (ΔSBP), pulse pressure (ΔPP), and ΔdP/dt during dobutamine administration were 0.94, 0.96, and 0.96, respectively. The mean values of the correlation coefficients of ΔS1amp with ΔSBP, ΔPP, and ΔdP/dt during esmolol administration were 0.80, 0.82, and 0.86, respectively. The hemodynamic changes caused by the administration of phenylephrine and nicardipine did not correlate significantly with changes in the heart rate. The S1 amplitude of the heart sound was significantly correlated with the hemodynamic changes caused by the changes in cardiac contractility but not with the variations in the vascular resistance. Heart sounds can potentially provide a non-invasive monitoring method to differentiate the cause of hemodynamic variations.


Assuntos
Ruídos Cardíacos , Propanolaminas , Animais , Suínos , Dobutamina/farmacologia , Nicardipino , Hemodinâmica , Fenilefrina/farmacologia
5.
Adv Mater ; : e2310015, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38450812

RESUMO

Negative-differential-resistance (NDR) devices offer a promising pathway for developing future computing technologies characterized by exceptionally low energy consumption, especially multivalued logic computing. Nevertheless, conventional approaches aimed at attaining the NDR phenomenon involve intricate junction configurations and/or external doping processes in the channel region, impeding the progress of NDR devices to the circuit and system levels. Here, an NDR device is presented that incorporates a channel without junctions. The NDR phenomenon is achieved by introducing a metal-insulator-semiconductor capacitor to a portion of the channel area. This approach establishes partial potential barrier and well that effectively restrict the movement of hole and electron carriers within specific voltage ranges. Consequently, this facilitates the implementation of both a ternary inverter and a ternary static-random-access-memory, which are essential components in the development of multivalued logic computing technology.

6.
Front Oncol ; 14: 1355454, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38482208

RESUMO

Background and aims: With the rapid growth of artificial intelligence (AI) applications in various fields, understanding its impact on liver cancer research is paramount. This scientometrics project aims to investigate publication trends and topics in AI-related publications in liver cancer. Materials and Methods: We employed a search strategy to identify AI-related publications in liver cancer using Scopus database. We analyzed the number of publications, author affiliations, and journals that publish AI-related publications in liver cancer. Finally, the publications were grouped based on intended application. Results: We identified 3950 eligible publications (2695 articles, 366 reviews, and 889 other document types) from 1968 to August 3, 2023. There was a 12.7-fold increase in AI-related publications from 2013 to 2022. By comparison, the number of total publications on liver cancer increased by 1.7-fold. Our analysis revealed a significant shift in trends of AI-related publications on liver cancer in 2019. We also found a statistically significant consistent increase in numbers of AI-related publications over time (tau = 0.756, p < 0.0001). Eight (53%) of the top 15 journals with the most publications were radiology journals. The largest number of publications were from China (n=1156), the US (n=719), and Germany (n=236). The three most common publication categories were "medical image analysis for diagnosis" (37%), "diagnostic or prognostic biomarkers modeling & bioinformatics" (19%), and "genomic or molecular analysis" (18%). Conclusion: Our study reveals increasing interest in AI for liver cancer research, evidenced by a 12.7-fold growth in related publications over the past decade. A common application of AI is in medical imaging analysis for various purposes. China, the US, and Germany are leading contributors.

7.
Nano Lett ; 24(10): 2939-2952, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477054

RESUMO

Advanced heterogeneous integration technologies are pivotal for next-generation electronics. Single-crystalline materials are one of the key building blocks for heterogeneous integration, although it is challenging to produce and integrate these materials. Remote epitaxy is recently introduced as a solution for growing single-crystalline thin films that can be exfoliated from host wafers and then transferred onto foreign platforms. This technology has quickly gained attention, as it can be applied to a wide variety of materials and can realize new functionalities and novel application platforms. Nevertheless, remote epitaxy is a delicate process, and thus, successful execution of remote epitaxy is often challenging. Here, we elucidate the mechanisms of remote epitaxy, summarize recent breakthroughs, and discuss the challenges and solutions in the remote epitaxy of various material systems. We also provide a vision for the future of remote epitaxy for studying fundamental materials science, as well as for functional applications.

8.
ACS Appl Mater Interfaces ; 16(12): 15286-15297, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38481185

RESUMO

We demonstrate an understanding of different physicochemical properties of copolymers induced by systematic changes in their structural parameters, i.e., the chemical structure of the comonomer unit, composition, molecular weight, and dispersity. The terpolymers were designed to be implemented in a chemically amplified resist (CAR) to form negative-tone patterns. With two basic repeating units of 4-hydroxystyrene and 2-ethyl-2-methacryloxyadamantane as monomers for conventional CARs, the pendant group of the third methacrylate comonomer was varied from aromatic, aliphatic lactone to lactone rings to modulate the interaction capability of the copolymer chains with n-butyl acetate, which is a negative-tone developer. Along with these structures, the monomer composition, molecular weight, and dispersity were also controlled. Physicochemical properties of the synthesized copolymers having controlled structures, i.e., dissolution behaviors and quantified Hansen solubility parameters, surface wetting characteristics, and surface roughness, which can be important properties affecting patterning capability in high-resolution lithography, were explored. Furthermore, the feasibility to use experimentally determined Hansen solubility parameters of the copolymers for the prediction of pattern formation using a coarse-grained model was assessed. Our comprehensive studies on the correlation of the structural parameters of the copolymers with final properties offer fundamental avenues to attain effective designs of the complex CAR system toward the lithographic process to achieve a sub-10 nm dimension, which is close to a single-chain dimension.

9.
J Clin Med ; 13(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38256575

RESUMO

Acne scars, particularly atrophic ones, present a persistent challenge in cosmetic medicine and surgery, requiring extended and multifaceted treatment approaches. Poly-(lactic acid) injectable fillers show promise in managing atrophic acne scars by stimulating collagen synthesis. However, the utilization of needle-free injectors for delivering poly-(lactic acid) into scars remains an area requiring further exploration. In this article, a summary of the latest advancements in needle-free jet injectors is provided, specifically highlighting the variations in jet-producing mechanisms. This summary emphasizes the differences in how these mechanisms operate, offering insights into the evolving technology behind needle-free injection systems. The literature review revealed documented cases focusing on treating atrophic acne scars using intralesional poly-(lactic acid) injections. The results of these clinical studies could be supported by separate in vitro and animal studies, elucidating the feasible pathways through which this treatment operates. However, there is limited information on the use of needle-free jet injectors for the intradermal delivery of poly-(lactic acid). Clinical cases of atrophic acne scar treatment are presented to explore this novel treatment concept, the needle-free delivery of poly-(lactic acid) using a jet pressure-based injector. The treatment demonstrated efficacy with minimal adverse effects, suggesting its potential for scar treatment. The clinical efficacy was supported by histological evidence obtained from cadaver skin, demonstrating an even distribution of injected particles in all layers of the dermis. In conclusion, we suggest that novel needle-free injectors offer advantages in precision and reduce patient discomfort, contributing to scar improvement and skin rejuvenation. Further comprehensive studies are warranted to substantiate these findings and ascertain the efficacy of this approach in scar treatment on a larger scale.

10.
Osteoporos Int ; 35(4): 635-644, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38095696

RESUMO

Periodontal disease and increased missing teeth were associated with incident vertebral fractures. In contrast, professional dental cleaning and frequent tooth brushing, was associated with a lower risk of vertebral fracture. Better oral hygiene care attenuated the risk associated with dental diseases. PURPOSE: To investigate the association between oral health and the risk of vertebral fractures. METHODS: We included 2,532,253 individuals aged ≥40 years who underwent the Korean National Health Insurance Service health examinations in 2008 and followed up until December 31, 2017. We performed multivariable Cox proportional hazard regression analyses to evaluate the association between dental diseases and oral hygiene care and the risk of vertebral fractures. RESULTS: Over the 9.3-year median follow-up, 1.46% (n = 36,857) experienced vertebral fractures. Individuals with dental diseases had a higher risk of vertebral fracture than those without (hazard ratio [HR] 1.04, 95% confidence interval [CI]: 1.02-1.07 for periodontal diseases; 1.02, 1.00-1.05 for dental caries; 1.12, 1.05-1.20 for ≥15 missing teeth). Good oral hygiene care was associated with a lower vertebral fracture risk (HR 0.89, 95% CI: 0.86-0.91 for ≥1 time/year [vs. <1 time/year] of professional dental cleaning; 0.90, 0.87-0.93 for ≥2 times/day [vs. 0-1 time/day] of toothbrushing). The combined dental diseases was significantly associated with an increased vertebral fracture risk, whereas combined oral hygiene care was associated with further risk reduction. Better oral hygiene care reduced vertebral fracture risk associated with dental diseases (all P <0.001). CONCLUSION: Periodontal disease, dental caries, and an increased number of missing teeth were independently associated with higher risks for vertebral fractures. Conversely, improved oral hygiene care, such as personal dental cleaning and frequent tooth brushing, may modify vertebral fracture risks associated with dental disease.


Assuntos
Cárie Dentária , Doenças Periodontais , Fraturas da Coluna Vertebral , Humanos , Higiene Bucal , Estudos de Coortes , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Doenças Periodontais/complicações , Doenças Periodontais/epidemiologia
11.
Int J Biol Macromol ; 257(Pt 1): 128598, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38056742

RESUMO

A wound healing substitute promotes rapid tissue regeneration and protects wound sites from microbial contamination. The silver-based antiseptic frequently moist skin stains, burns and irritation, penetrates deep wounds and protects against pathogenic infections. Thus, we formulated a novel fibrin/chitosan encapsulated silver nanoparticle (CH:F:SPG-CH:SNP) composites bandage accelerating the polymicrobial wound healing. Electrospinning method was employed to form the nano-porous, inexpensive, and biocompatible smart bandages. The structural, functional, and mechanical properties were analyzed for the prepared composites. The biological capacity of prepared CH:F:SPG-CH:SNP bandage was assessed against NIH-3 T3 fibroblast and HaCaT cell lines. In vitro hemolytic assays using red blood cells were extensively studied and explored the low hemolytic effect (4.5 %). In addition, the improved drug delivery nature captured for the CH:F:SPG-CH:SNP composite bandage. Antibacterial experiments were achieved against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Lactobacillus bulgaricus using zone inhibition method. Moreover, in-vivo wound healing efficacy of fabricated smart bandage was evaluated on the albino Wistar rats which revealed the significant improvement on the postoperative abdomen wounds.


Assuntos
Quitosana , Nanopartículas Metálicas , Nanocompostos , Ratos , Animais , Prata/farmacologia , Prata/química , Quitosana/farmacologia , Quitosana/química , Nanopartículas Metálicas/química , Antibacterianos/química , Cicatrização , Ratos Wistar , Nanocompostos/química
12.
Int J Biol Macromol ; 256(Pt 1): 128458, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38016611

RESUMO

Cerium dioxide (CeO2) based nanomaterials have emerged as promising dermal equivalents, promoting fibroblast infiltration and tissues regeneration. To enhance the antibacterial and wound healing activity, herein chitosan (CS)-CeO2 combined nano titanium dioxide (TiO2) complex loaded polycaprolactone (PCL) nanohybrid (CS-CeO2/TiO2/PCL) scaffolds were prepared through casting method. The nanohybrid scaffolds' physiochemical, morphological, mechanical, and biological properties were evaluated using advanced analytical techniques. Fourier transform infrared spectroscopy spectrum evidently depicted the various intermolecular interactions on the nanohybrid scaffolds. The developed scaffold exhibited the high swelling behavior and good degradability and permeability which is beneficial for absorbing wound transudation to fasten the healing efficacy. Moreover, CS-CeO2/TiO2/PCL scaffolds owned the better antibacterial activity against bacterial strains E. coli and S. aureus. Also, MTT assay on fibroblast (NIH 3T3) cells and immortalized human keratinocytes (HaCaT) cells indicated improved cell viability and proliferation. In vivo results revealed that the fabricated scaffold full aid to complete wound closure after 14 days which showed CS-CeO2/TiO2/PCL as the significant wound dressing material with potential antibacterial immunity.


Assuntos
Quitosana , Poliésteres , Titânio , Humanos , Quitosana/química , Staphylococcus aureus , Escherichia coli , Antibacterianos/química , Cicatrização
13.
ACS Omega ; 8(47): 45088-45095, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38046304

RESUMO

We couple halide vapor phase epitaxy (HVPE) growth of III-V materials with liftoff from an ultrathin carbon release layer to address two significant cost components in III-V device - epitaxial growth and substrate reusability. We investigate nucleation and growth of GaAs layers by HVPE on a thin amorphous carbon layer that can be mechanically exfoliated, leaving the substrate available for reuse. We study nucleation as a function of carbon layer thickness and growth rate and find island-like nucleation. We then study various GaAs growth conditions, including V/III ratio, growth temperature, and growth rate in an effort to minimize film roughness. High growth rates and thicker films lead to drastically smoother surfaces with reduced threading dislocation density. Finally, we grow an initial photovoltaic device on a carbon release layer that has an efficiency of 7.2%. The findings of this work show that HVPE growth is compatible with a carbon release layer and presents a path toward lowering the cost of photovoltaics with high throughput growth and substrate reuse.

14.
Nat Mater ; 22(12): 1470-1477, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38012388

RESUMO

Three-dimensional (3D) hetero-integration technology is poised to revolutionize the field of electronics by stacking functional layers vertically, thereby creating novel 3D circuity architectures with high integration density and unparalleled multifunctionality. However, the conventional 3D integration technique involves complex wafer processing and intricate interlayer wiring. Here we demonstrate monolithic 3D integration of two-dimensional, material-based artificial intelligence (AI)-processing hardware with ultimate integrability and multifunctionality. A total of six layers of transistor and memristor arrays were vertically integrated into a 3D nanosystem to perform AI tasks, by peeling and stacking of AI processing layers made from bottom-up synthesized two-dimensional materials. This fully monolithic-3D-integrated AI system substantially reduces processing time, voltage drops, latency and footprint due to its densely packed AI processing layers with dense interlayer connectivity. The successful demonstration of this monolithic-3D-integrated AI system will not only provide a material-level solution for hetero-integration of electronics, but also pave the way for unprecedented multifunctional computing hardware with ultimate parallelism.

15.
Comput Biol Med ; 166: 107532, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37816272

RESUMO

Premature ventricular contraction (PVC) is a common and harmless cardiac arrhythmia that can be asymptomatic or cause palpitations and chest pain in rare instances. However, frequent PVCs can lead to more serious arrhythmias, such as atrial fibrillation. Several PVC detection models have been proposed to enable early diagnosis of arrhythmias; however, they lack reliability and generalizability due to the variability of electrocardiograms across different settings and noise levels. Such weaknesses are known to aggravate with new data. Therefore, we present a deep learning model with a novel attention mechanism that can detect PVC accurately, even on unseen electrocardiograms with various noise levels. Our method, called the Denoise and Contrast Attention Module (DCAM), is a two-step process that denoises signals with a convolutional neural network (CNN) in the frequency domain and attends to differences. It focuses on differences in the morphologies and intervals of the remaining beats, mimicking how trained clinicians identify PVCs. Using three different encoder types, we evaluated 1D U-Net with DCAM on six external test datasets. The results showed that DCAM significantly improved the F1-score of PVC detection performance on all six external datasets and enhanced the performance of balancing both the sensitivity and precision of the models, demonstrating its robustness and generalization ability regardless of the encoder type. This demonstrates the need for a trainable denoising process before applying the attention mechanism. Our DCAM could contribute to the development of a reliable algorithm for cardiac arrhythmia detection under real clinical electrocardiograms.

16.
Food Sci Biotechnol ; 32(13): 1901-1911, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37781055

RESUMO

This study investigated the effects of temperature, pH, and starch genotype on starch characteristics after dry heat treatment (DHT). DHT starches were prepared according to 19 DHT conditions, constructed using a D-optimal design, and analyzed with respect to apparent amylose (AAM) content, X-ray diffraction (XRD) pattern, relative crystallinity (RC), solubility and swelling power (SP), thermal properties, and pasting viscosity. The DHT starches maintained their granular structures even after DHT at pH 3, although there was some damage to their granular surfaces. The DHT starches showed lower amylose content, RC, SP, gelatinization temperature and enthalpy, degree of retrogradation, and pasting viscosity, but higher solubility, compared to those of native starches. These DHT effects were more pronounced as pH decreased at each temperature, regardless of the starch genotype. Overall, DHT can be used to expand the physical functionality of high-amylose and highly crystallized starches with poor properties. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01353-7.

17.
Nanomaterials (Basel) ; 13(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37887901

RESUMO

Organic-inorganic hybrid perovskite materials continue to attract significant interest due to their optoelectronic application. However, the degradation phenomenon associated with hybrid structures remains a challenging aspect of commercialization. To overcome the stability issue, we have assembled the methylammonium lead bromide nano islands (MNIs) on the backbone of poly-3-dodecyl-thiophene (PDT) for the first time. The structural and morphological properties of the MNI-PDT composite were confirmed with the aid of X-ray diffraction (XRD) studies, Field emission scanning electron microscope (FESEM), and X-ray photoelectron spectroscopy (XPS). The optical properties, namely absorption studies, were carried out by ultraviolet-visible spectroscopy. The fluorescent behavior is determined by photoluminescence (PL) spectroscopy. The emission peak for the MNI-PDT was observed at 536 nm. The morphology studies supported by FESEM indicated that the nano islands are completely covered on the surface of the polymer backbone, making the hybrid (MNI-PDT) stable under environmental conditions for three months. The interfacial interaction strategy developed in the present work will provide a new approach for the stabilization of hybrids for a longer time duration.

18.
ACS Nano ; 17(21): 21678-21689, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37843425

RESUMO

In this study, we investigate the thermochemical stability of graphene on the GaN substrate for metal-organic chemical vapor deposition (MOCVD)-based remote epitaxy. Despite excellent physical properties of GaN, making it a compelling choice for high-performance electronic and light-emitting device applications, the challenge of thermochemical decomposition of graphene on a GaN substrate at high temperatures has obstructed the achievement of remote homoepitaxy via MOCVD. Our research uncovers an unexpected stability of graphene on N-polar GaN, thereby enabling the MOCVD-based remote homoepitaxy of N-polar GaN. Our comparative analysis of N- and Ga-polar GaN substrates reveals markedly different outcomes: while a graphene/N-polar GaN substrate produces releasable microcrystals (µCs), a graphene/Ga-polar GaN substrate yields nonreleasable thin films. We attribute this discrepancy to the polarity-dependent thermochemical stability of graphene on the GaN substrate and its subsequent reaction with hydrogen. Evidence obtained from Raman spectroscopy, electron microscopic analyses, and overlayer delamination points to a pronounced thermochemical stability of graphene on N-polar GaN during MOCVD-based remote homoepitaxy. Molecular dynamics simulations, corroborated by experimental data, further substantiate that the thermochemical stability of graphene is reliant on the polarity of GaN, due to different reactions with hydrogen at high temperatures. Based on the N-polar remote homoepitaxy of µCs, the practical application of our findings was demonstrated in fabrication of flexible light-emitting diodes composed of p-n junction µCs with InGaN heterostructures.

19.
Sci Adv ; 9(42): eadj5379, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37862426

RESUMO

The concept of remote epitaxy involves a two-dimensional van der Waals layer covering the substrate surface, which still enable adatoms to follow the atomic motif of the underlying substrate. The mode of growth must be carefully defined as defects, e.g., pinholes, in two-dimensional materials can allow direct epitaxy from the substrate, which, in combination with lateral epitaxial overgrowth, could also form an epilayer. Here, we show several unique cases that can only be observed for remote epitaxy, distinguishable from other two-dimensional material-based epitaxy mechanisms. We first grow BaTiO3 on patterned graphene to establish a condition for minimizing epitaxial lateral overgrowth. By observing entire nanometer-scale nuclei grown aligned to the substrate on pinhole-free graphene confirmed by high-resolution scanning transmission electron microscopy, we visually confirm that remote epitaxy is operative at the atomic scale. Macroscopically, we also show variations in the density of GaN microcrystal arrays that depend on the ionicity of substrates and the number of graphene layers.

20.
Water Environ Res ; 95(10): e10935, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37795743

RESUMO

Soil and water pollution is of significant concern worldwide because of the consequences of environmental degradation and harmful effects on human health. Water bodies are very much polluted by various organic and inorganic pollutants by different human activities, including industrial wastes. Environmental pollution remains high because of urbanization-induced industrial developments and human lifestyle. It accumulates pollutants in the environment including plants and living organisms. Even mothers' milk is poisoned because of the uncontrolled, widespread increase in pollution. The discharge levels of organic hydrophobic contaminants in the water and soil are increasing rapidly. This severe pollution must be remediated to upgrade the environment and ensure the safety of human beings. It is vital to eradicate soil and water pollution to guarantee sufficient food and water. Different techniques available to remove the pollutants vary according to the type of pollutants. Hydrophobic contaminants are more dangerous than heavy metals and other pollutants; they cannot be easily removed, requiring special care. Hydrophobic organoxenobiotics released in the environment pose severe contamination in soil and water. Therefore, developing efficient and cost-effective processes is necessary to remove hydrophobic contaminants from soil and water. With nanoparticle-mediated remediation techniques, the green-synthesized nanoparticles exhibit improved performance. This review consolidates reports on the remediation techniques of hydrophobic contaminants, focusing on green-synthesized remediation agents. The very limited works on green synthesis of polymeric nanoparticles, particularly polyurethane-based materials for organic contaminants removal demand more attention in this area. PRACTITIONER POINTS: Consolidated the effects of hydrophobic organic and plastic contaminants on environment degradation. Summarized the advantages of green synthesized polymer nanoparticles for efficient removal of hydrophobic contaminants. Discussed the different sources of pollution and remediation techniques referring 112 research works.


Assuntos
Poluentes Ambientais , Metais Pesados , Nanopartículas , Poluentes do Solo , Humanos , Polímeros , Água , Poluentes do Solo/análise , Resíduos Industriais , Solo
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