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1.
Clin Exp Allergy ; 54(2): 93-108, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38321912

RESUMO

OBJECTIVE: Understanding factors that impact health-related quality of life (HRQL) is essential to inform personalised food allergy management. However, there are inconsistencies about the impact of gender on HRQL in food allergy. This review aimed to collate all investigations of the association between gender and total or subdomain HRQL scores of individuals with food allergy and their caregivers. DESIGN: This is a narrative systematic review. We descriptively synthesised and compared HRQL outcomes by participant and parent genders according to statistical and clinical significance. Study quality was assessed using the ROBINS-I, inclusive of all domains. Sensitivity analysis of non-interventional studies was conducted using the ROBINS-E. DATA SOURCES: A systematic search of Medline and Embase databases was conducted on 4 April 2022 and updated on 5 December 2023. ELIGIBILITY CRITERIA: Studies were eligible for inclusion if they reported original data on the association between any sex and/or gender and HRQL, as measured with any validated instrument, in populations with IgE-mediated food allergy. Interventional and non-interventional studies were eligible. RESULTS: A comparison of 34 eligible studies (10 interventional and 24 non-interventional) indicated females with food allergy (62.5% of studies of children, 83.3% of studies of adults) and mothers of children with food allergy (50% of studies of caregivers) experienced poorer self-reported baseline HRQL than their counterparts, notably in domains of physical, emotional or food anxiety-related well-being. Gender differences in child HRQL after food allergen immunotherapy were observed. However, selective reporting in included interventional studies meant the direction of this association could not be determined. The proxy-reported total HRQL of participants was not affected by caregiver gender, nor was caregiver HRQL likely impacted by child gender. CONCLUSIONS: Gender should be considered an important modifier of participant HRQL outcomes in food allergy studies. Purposeful exploration of HRQL in all genders is needed to fully understand the implications of this construct on the lived experience of food allergy. SYSTEMATIC REVIEW REGISTRATION: PROSPERO (CRD42022329901).


Assuntos
Hipersensibilidade Alimentar , Qualidade de Vida , Adulto , Criança , Humanos , Masculino , Feminino , Qualidade de Vida/psicologia , Cuidadores , Inquéritos e Questionários , Hipersensibilidade Alimentar/psicologia , Alérgenos , Imunoglobulina E
2.
Muscle Nerve ; 68(5): 775-780, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37682022

RESUMO

INTRODUCTION/AIMS: ADSSL1 myopathy (OMIM 617030) is a recently discovered, congenital myopathic disease caused by a pathogenic variant in ADSSL1. ADSSL1 is an enzyme involved in the purine nucleotide process and facilitates the conversion of inosine monophosphate to adenosine monophosphate within myocytes. Electrical impedance myography (EIM) is a portable, non-invasive, and cost-effective method for characterizing muscle integrity. Three ADSSL1 patients are presented in whom characterization of muscle integrity using EIM was performed. METHODS: A 15-y-old male, 20-y-old female, and 63-y-old male each with a pathogenic variant in ADSSL1 [c.901G > A] as well as three, age-gender matched healthy controls (HCs) were enrolled. Study participants were phenotyped using a virtual EIM procedure. RESULTS: ADSSL1 myopathy patients presented with variable onset of physical disability, disease progression, and severity of muscle weakness. Across multiple proximal and distal muscles groups and relative to HCs, ADSSL1 myopathy patients demonstrated lower phase and reactance values, while resistance was higher, which together indicated diseased muscle. DISCUSSION: EIM can provide a novel, non-invasive and objective biomarker to evaluate muscle integrity in patients with ADSSL1 myopathy. Combining EIM with musculoskeletal imaging and histologic assessments in follow-up studies may further inform on the pathophysiology of ADSSL1 myopathy.

3.
J Allergy Clin Immunol Pract ; 11(10): 3195-3202.e4, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37423341

RESUMO

BACKGROUND: Food allergy adversely affects the health-related quality of life (HRQoL) of patients. It is unclear whether factors such as the reaction eliciting dose (ED) and the nature of allergic reaction symptoms affect HRQoL. OBJECTIVE: To explore associations between reaction ED or the nature of allergic symptoms and HRQoL among children with peanut allergy. METHODS: This study was a secondary analysis of baseline data from the PPOIT-003 randomized trial in 212 children aged 1 to 10 years with challenge-confirmed peanut allergy. Children's past reaction symptoms were collected by clinicians during screening. Associations between variables of interest and parent-reported child-proxy HRQoL were examined by univariable and multivariable linear regression. RESULTS: Mean age of study participants was 5.9 years; 63.2% were male. Children with a low reaction ED of 80 mg peanut protein had significantly poorer HRQoL (ß = -0.81; 95% CI, -1.61 to -0.00; P = .049) compared with children with a high ED of 2,500 mg peanut protein. Gastrointestinal symptoms (ß = 0.45; 95% CI, 0.03-0.87; P = .037), lower airway symptoms (ß = 0.46; 95% CI, 0.05-0.87; P = .030), multisystem involvement (ß = 0.71; 95% CI, 0.25-1.16; P = .003), or anaphylaxis (ß = 0.46; 95% CI, 0.04-0.87; P = .031) during a previous reaction were associated with worse HRQoL. CONCLUSIONS: Peanut-allergic children with a lower allergen reaction threshold experienced a greater negative HRQoL impact compared with children with higher reaction thresholds. In addition, specific past allergic reaction symptoms were associated with comparatively worse HRQoL. Children experiencing these symptoms and those with lower reaction ED require increased clinical support to manage the food allergy and are likely to benefit from interventions that can improve HRQoL.

4.
Adv Sci (Weinh) ; 10(11): e2207109, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36752398

RESUMO

This study demonstrates the intercalation of single-atom Ni (NiSA ) substantially reduces the reaction activity of Ni oxide supported Pd nanoparticle (NiO2 /Pd) in the oxygen reduction reaction (ORR). The results indicate the transition states kinetically consolidate the adsorption energy for the chemisorbed O and OH species on the ORR activity. Notably, the NiO2 /Ni1 /Pd performs the optimum ORR behavior with the lowest barrier of 0.49 eV and moderate second-step barrier of 0.30 eV consequently confirming its utmost ORR performance. Through the stepwise cross-level demonstrations, a structure-Eads -ΔE correspondence for the proposed NiO2 /Nin /Pd systems is established. Most importantly, such a correspondence reveals that the electronic structure of heterogeneous catalysts can be significantly differed by the segregation of atomic clusters in different dimensions and locations. Besides, the doping-depth effect exploration of the NiSA in the NiO2 /Pd structure intrinsically elucidates that the Ni atom doping in the subsurface induces the most fruitful NiSA /PdML synergy combining the electronic and strain effects to optimize the ORR, whereas this desired synergy diminishes at high Pd coverages. Overall, the results not only rationalize the variation in the redox properties but most importantly provides a precision evaluation of the process window for optimizing the configuration and composition of bimetallic catalysts in practical experiments.

5.
Sci Rep ; 12(1): 20908, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463382

RESUMO

Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare disorder involving skeletal dysplasia and heterotopic ossification (HO) of muscle and connective tissue. We aimed to define a novel biomarker in FOP that enables reliable assessment of musculoskeletal tissue integrity. Considering logistical difficulties that FOP patients often face, our goal was to identify an at-home biomarker technique. Electrical impedance myography (EIM) is a non-invasive, portable method that can inform on muscle health. 15 FOP patients (age 10-52) and 13 healthy controls were assessed. Using EIM, multiple muscle groups were characterized per participant in a 45-min period. The Cumulative Analogue Joint Involvement Scale (CAJIS) was implemented to determine mobility burden severity. We additionally evaluated physical activity levels via a Patient-Reported Outcomes Measurement Information System (PROMIS)-based questionnaire. Relative to controls, FOP patients demonstrated significantly lower regional and whole-body phase values at 50 kHz and 100 kHz, indicating more diseased muscle tissue. Lower whole-body phase and reactance values, and higher resistance values, were associated with greater FOP burden (CAJIS score range: 4-30) and lower physical activity levels at 50 kHz and 100 kHz. This study points to the potential utility of EIM as a clinical biomarker tool capable of characterizing muscle integrity in FOP.


Assuntos
Miosite Ossificante , Osteocondrodisplasias , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Impedância Elétrica , Músculos , Miografia
6.
Plant Genome ; 15(3): e20223, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35666039

RESUMO

The tomato (Solanum lycopersicum L.) family, Solanaceae, is a model clade for a wide range of applied and basic research questions. Currently, reference-quality genomes are available for over 30 species from seven genera, and these include numerous crops as well as wild species [e.g., Jaltomata sinuosa (Miers) Mione and Nicotiana attenuata Torr. ex S. Watson]. Here we present the genome of the showy-flowered Andean shrub Iochroma cyaneum (Lindl.) M. L. Green, a woody lineage from the tomatillo (Physalis philadelphica Lam.) subfamily Physalideae. The assembled size of the genome (2.7 Gb) is more similar in size to pepper (Capsicum annuum L.) (2.6 Gb) than to other sequenced diploid members of the berry clade of Solanaceae [e.g., potato (Solanum tuberosum L.), tomato, and Jaltomata]. Our assembly recovers 92% of the conserved orthologous set, suggesting a nearly complete genome for this species. Most of the genomic content is repetitive (69%), with Gypsy elements alone accounting for 52% of the genome. Despite the large amount of repetitive content, most of the 12 I. cyaneum chromosomes are highly syntenic with tomato. Bayesian concordance analysis provides strong support for the berry clade, including I. cyaneum, but reveals extensive discordance along the backbone, with placement of chili pepper and Jaltomata being highly variable across gene trees. The I. cyaneum genome contributes to a growing wealth of genomic resources in Solanaceae and underscores the need for expanded sampling of diverse berry genomes to dissect major morphological transitions.


Assuntos
Capsicum , Solanum lycopersicum , Solanum tuberosum , Teorema de Bayes , Capsicum/genética , Flores , Frutas , Genoma de Planta , Solanum lycopersicum/genética , Solanum tuberosum/genética
7.
Muscle Nerve ; 66(3): 354-361, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35727064

RESUMO

INTRODUCTION/AIMS: We assessed the classification performance of machine learning (ML) using multifrequency electrical impedance myography (EIM) values to improve upon diagnostic outcomes as compared to those based on a single EIM value. METHODS: EIM data was obtained from unilateral excised gastrocnemius in eighty diseased mice (26 D2-mdx, Duchenne muscular dystrophy model, 39 SOD1G93A ALS model, and 15 db/db, a model of obesity-induced muscle atrophy) and 33 wild-type (WT) animals. We assessed the classification performance of a ML random forest algorithm incorporating all the data (multifrequency resistance, reactance and phase values) comparing it to the 50 kHz phase value alone. RESULTS: ML outperformed the 50 kHz analysis as based on receiver-operating characteristic curves and measurement of the area under the curve (AUC). For example, comparing all diseases together versus WT from the test set outputs, the AUC was 0.52 for 50 kHz phase, but was 0.94 for the ML model. Similarly, when comparing ALS versus WT, the AUCs were 0.79 for 50 kHz phase and 0.99 for ML. DISCUSSION: Multifrequency EIM using ML improves upon classification compared to that achieved with a single-frequency value. ML approaches should be considered in all future basic and clinical diagnostic applications of EIM.


Assuntos
Esclerose Lateral Amiotrófica , Miografia , Algoritmos , Esclerose Lateral Amiotrófica/diagnóstico , Animais , Impedância Elétrica , Aprendizado de Máquina , Camundongos , Camundongos Endogâmicos mdx , Músculo Esquelético
8.
Phys Chem Chem Phys ; 23(33): 18012-18025, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34612275

RESUMO

The crux of the hot topic concerning the widespread replacement of fuel cells (FCs) with traditional petrochemical energy is to balance improving the oxygen reduction reaction (ORR) and reducing the cost. The present study employs density functional theory (DFT) to investigate the effect of Pt ensemble size regulation from a single atom to full coverage on the physio-chemical properties, oxygen adsorption energies and overall ORR efficiency of bimetallic nanocatalysts (NCs) with a Cocore-Pdshell structure. Our results reveal that the electronegativity difference and lattice strain between neighboring heteroatoms are enhanced to trigger a synergetic effect in local domains, with the Pt cluster size reduced from nanometers to subnanometers. They induce a directed and tunable charge relocation mechanism from deep Co to topmost Pt to optimize the adsorption energies of O2/O* and achieve excellent ORR kinetics performance with minimum Pt usage but maximum Pt atom utilization (i.e., Pt1 to Pt3) compared with benchmark Pt(111). Such a dependency between the cluster size and corresponding ORR performance for the established Co@Pd-Ptn system can be applied to accurately guide the experimental synthesis of ordered heterogeneous catalysts (e.g., other core@shell-clusters structures) toward low Pt, high efficiency and green economy.

9.
Science ; 371(6524): 76-78, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33384375

RESUMO

Diamond is not only the hardest material in nature, but is also an extreme electronic material with an ultrawide bandgap, exceptional carrier mobilities, and thermal conductivity. Straining diamond can push such extreme figures of merit for device applications. We microfabricated single-crystalline diamond bridge structures with ~1 micrometer length by ~100 nanometer width and achieved sample-wide uniform elastic strains under uniaxial tensile loading along the [100], [101], and [111] directions at room temperature. We also demonstrated deep elastic straining of diamond microbridge arrays. The ultralarge, highly controllable elastic strains can fundamentally change the bulk band structures of diamond, including a substantial calculated bandgap reduction as much as ~2 electron volts. Our demonstration highlights the immense application potential of deep elastic strain engineering for photonics, electronics, and quantum information technologies.

10.
Phys Chem Chem Phys ; 23(3): 1822-1834, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33393548

RESUMO

The development of electrocatalysts with reconcilable balance between the cost and performance in oxygen reduction reaction (ORR) is an imperative task for the widespread adoption of fuel cell technology. In this study, we proposed a unique model of diatomic Pt-cluster (Pt-dimer) in the topmost layer of the Co/Pd bimetallic slab (Co@Pd-Pt2) for mimicking the Cocore@Pdshell nanocatalysts (NCs) surface and systematically investigating its local-regional collaboration pathways in ORR by density functional theory (DFT). The results demonstrate that the Pt-dimer produces local differentiation from both ligand and geometric effects on the Co@Pd surface, which forms adsorption energy (Eads) gradients for relocating the ORR-adsorbates. Our calculations for Eads-variations of ORR-species, reaction coordinates, and intraparticle charge injection propose and confirm a novel local synergetic collaboration around the Pt-dimer in the Co@Pd-Pt2 system with the best-performing ORR behavior compared with all reference models. With proper selection of the composition in intraparticle components, the proposed DFT assessments could be adopted for developing economical and high-performance catalysts in various heterogeneous reactions.

11.
J Pharm Biomed Anal ; 192: 113647, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33010501

RESUMO

In this study, we aimed to identify the cultivatable oral anaerobic bacterial distribution in oral cavity by MALDI-TOF Biotyper. The bacterial distribution of three groups, including subjects with/without periodontal disease, two clusters of age (60 years as the cutoff), and before/after treatment, were investigated in this study. There were 38 participants recruited in this study, involving 18 subjects with moderate to severe periodontal-infected patients and 20 healthy controls. Total number of 126 bacterial species were identified by MALDI-TOF MS. The relative abundance of Streptococcus gordonii and Streptococcus intermedius in periodontal patients is higher than healthy controls indicating potential biomarkers for periodontal disease. Participants with periodontal disease were subdivided in to two clusters of age (60 years as the cutoff), 11 and 7 participants were age <60 years and>60 years, respectively. Meanwhile, the incidence of Streptococcus pneumoniae and Streptococcus oralis infection were higher in the subjects above 60 years old than below. Moreover, the bacterial distribution between pre-treatment and post-treatment was similar indicating that basic treatment without the ability to redistribute the microbiota. In summary, the cultivable oral anaerobic bacteria were identified by MALDI-TOF MS and the bacterial distribution shifting was shown to be associated with the progress of periodontal disease to aging and basic treatment. This study provided information for diagnosis and treatment guidelines for oral healthcare.


Assuntos
Microbiota , Doenças Periodontais , Anaerobiose , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
12.
Chemistry ; 26(46): 10598-10606, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32496593

RESUMO

It is known that the interplay between molecules and active sites on the topmost surface of a solid catalyst determines its activity in heterogeneous catalysis. The electron density of the active site is believed to affect both adsorption and activation of reactant molecules at the surface. Unfortunately, commercial X-ray photoelectron spectroscopy, which is often adopted for such characterization, is not sensitive enough to analyze the topmost surface of a catalyst. Most researchers fail to acknowledge this point during their catalytic correlation, leading to different interpretations in the literature in recent decades. Recent studies on pristine Cu2 O [Nat. Catal. 2019, 2, 889; Nat. Energy 2019, 4, 957] have clearly suggested that the electron density of surface Cu is facet dependent and plays a key role in CO2 reduction. Herein, it is shown that pristine CeO2 can reach 2506/1133 % increase in phosphatase-/peroxidase-like activity if the exposed surface is wisely selected. By using NMR spectroscopy with a surface probe, the electron density of the surface Ce (i.e., the active site) is found to be facet dependent and the key factor dictating their enzyme-mimicking activities. Most importantly, the surface area of the CeO2 morphologies is demonstrated to become a factor only if surface Ce can activate the adsorbed reactant molecules.


Assuntos
Cério , Isoenzimas/química , Adsorção , Catálise , Cério/química , Oxirredução , Espectroscopia Fotoeletrônica
13.
J Crit Care ; 57: 79-83, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32062289

RESUMO

PURPOSE: Alert intensivists about the diagnostic pitfalls arising from hyperammonemia due to Ureaplasma infections in post-transplant patients. MATERIALS AND METHODS: Clinical observation of one patient. CASE REPORT: A 65-year-old female with a medical history of semi-recent kidney transplant was admitted to the Intensive Care Unit for refractory status epilepticus. There were no lesions on brain imaging. Bacterial cultures and viral PCR of cerebrospinal fluid were negative. The first blood ammonia level measured on day 2 was 13 times the normal level, but biological liver tests were normal. The persistence of elevated ammonia levels led to the initiation of symptomatic ammonia lowering-treatments and continuous renal replacement therapy, which led to its decrease without normalization. An Ureaplasma spp infection was then diagnosed. Levofloxacin and doxycyline were administered resulting in normalization of ammonia levels within 48 h. However repeat MRI showed diffuse cortical cytotoxic edema and the patient remained in a minimally conscious state. She eventually died 4 months later from a recurrent infection. CONCLUSION: Ureaplasma infection must be suspected in cases of neurological symptoms associated with hyperammonemia without liver failure, following an organ transplant. Only urgent treatment could improve the prognosis and prevent severe neurological damage or death.


Assuntos
Hiperamonemia/etiologia , Transplante de Rim/efeitos adversos , Estado Epiléptico/etiologia , Infecções por Ureaplasma/complicações , Ureaplasma , Idoso , Cuidados Críticos , Eletroencefalografia , Feminino , Humanos , Terapia de Imunossupressão , Imunossupressores/efeitos adversos , Unidades de Terapia Intensiva , Falência Renal Crônica/cirurgia , Imageamento por Ressonância Magnética , Reação em Cadeia da Polimerase , Complicações Pós-Operatórias , Prognóstico , Estado Epiléptico/diagnóstico , Infecções por Ureaplasma/tratamento farmacológico , Infecções por Ureaplasma/microbiologia
14.
J Phys Condens Matter ; 32(5): 055501, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31665125

RESUMO

Using first-principles calculations, we show that p-doped blue phosphorene can be obtained by molecular doping with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ) and 1,3,4,5,7,8-hexafluorotetracyanonaphthoquinodimethane (F6-TNAP), whereas n-doped blue phosphorene can be realized by doping with tetrathiafulvalene (TTF) and cyclooctadecanonaene (CCO). Moreover, the doping gap can be effectively modulated in each case by applying an external perpendicular electric field. The optical absorption of blue phosphorene can be considerably enhanced in a broad spectral range through the adsorption of CCO, F4-TCNQ, and F6-TNAP molecules, suggesting potential of the doped materials in the field of renewable energy.

15.
ACS Omega ; 4(4): 6339-6346, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459774

RESUMO

Modified embedded atom method potential parameters of beryllium oxide (BeO) have been developed, which can well reproduce the thermodynamic properties of beryllium oxide. To accurately describe the interactions between the atoms in the BeO structure, the density functional theory is used to calculate the fundamental properties such as the lattice constant, bulk modulus, and elastic constant, which are used for the potential fitting. The properties such as the enthalpy and specific heat are used to test the validity of the potential parameters. The calculated results by the developed potential parameters are compared with the experimental and other theoretical data as a function of temperature. The good agreement between the calculated results by the new potential and the experimental data verifies the potential parameters. The developed potential parameters have also been used to predict the thermal conductivity of BeO as a function of temperature for further applications of beryllium oxide.

16.
Sci Rep ; 9(1): 10940, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358813

RESUMO

Stacking faults, as defects of disordered crystallographic planes, are one of the most important slipping mechanisms in the commonly seen lattice, face-centered cubic (FCC). Such defects can initiate twinning which strengthens mechanical properties, e.g. twinning-induced plasticity (TWIP), of high entropy alloys (HEAs) at cryogenic temperatures. In this work, by using density functional theory (DFT), the twinning initiated from stacking faults is discussed with regard to two different solute elements, Al and Mo, in the FeNiCoCr HEAs. Our results show that adding aluminum (Al) has noticeable enhancement of twinnability while molybdenum (Mo) only induces more stacking faults in the FeNiCoCr-based HEAs.

17.
Sci Rep ; 9(1): 1299, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718703

RESUMO

Artificial graphite (FSN) additive is employed as internal structural label for projecting cyclability of Si material native electrode in a mass ratio of Si/FSN = 1.0 in Li ion battery (LIB). Results of operando X-ray diffraction analysis on Si-FSN negative electrode in LIB demonstrate that one can evaluate the lithiation and delithiation affinity of active material by referring phase transition delay of graphite as affected by experimental splits in a formation process of LIB. We prove that a thin layer of surface amorphous structure and residual lattice strain are formed in Si by high energy ball-milling treatment. Those manipulations improve Li intercalation kinetics and thus enabling a capacity fading of less than 10% (from 1860 to 1650 mAhg-1) for Si negative electrode in 50 cycles. Of utmost importance, this study discloses a robust assessment for revealing mechanism on amorphous and strain related silicide formation and predicting cyclability of negative electrode by quantitative phase evolution rate of FSN additive in LIB.

18.
Nat Commun ; 10(1): 440, 2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30683876

RESUMO

Advanced electrocatalysts with low platinum content, high activity and durability for the oxygen reduction reaction can benefit the widespread commercial use of fuel cell technology. Here, we report a platinum-trimer decorated cobalt-palladium core-shell nanocatalyst with a low platinum loading of only 2.4 wt% for the use in alkaline fuel cell cathodes. This ternary catalyst shows a mass activity that is enhanced by a factor of 30.6 relative to a commercial platinum catalyst, which is attributed to the unique charge localization induced by platinum-trimer decoration. The high stability of the decorated trimers endows the catalyst with an outstanding durability, maintaining decent electrocatalytic activity with no degradation for more than 322,000 potential cycles in alkaline electrolyte. These findings are expected to be useful for surface engineering and design of advanced fuel cell catalysts with atomic-scale platinum decoration.

19.
Nanoscale ; 10(48): 23164-23169, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30515499

RESUMO

Droplets are ubiquitous in nature and the preferential control of droplet transport offers limitless potential for efficient mass and momentum transfer as well as energy conversion. In this work, we show that even without the need for any external energy input, the self-propelled motion of droplets driven by a surface wetting gradient can lead to reliable electricity generation. Simple analytical analysis demonstrates that the output voltage results from the modulation of the surface charge distribution on the dynamically changing solid/liquid interfaces, which can be programmed by tailoring the wetting gradient and the size of the droplet. We demonstrate that a self-propelled 25 µL droplet can generate a peak current of 93.5 nA and a maximum output power of 2.4 nW. This work provides a new angle for optimizing energy harvesting devices based on liquid-solid interfaces.

20.
Phys Chem Chem Phys ; 20(38): 24726-24734, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30225488

RESUMO

Recently, van der Waals (vdW) two-dimensional heterostructures have attracted great attention. The combination structures demonstrate unique properties that individual layers do not possess, which foretell promising future applications. Here, we investigate the structural and electronic properties of SiC/graphene, SiC/MoS2, and graphene/SiC/MoS2 vdW heterostructures using first-principles calculations. The SiC/graphene interface forms a p-type Schottky contact, which can be turned into an n-type Schottky contact by applying an external electric field. Moreover, a transition from a Schottky to an Ohmic contact at the interface can be triggered by varying the interlayer distance or applying an external electric field. The SiC/MoS2 interface forms a type-II heterostructure, in which the recombination of photoexcited charges will be greatly suppressed. The transition from type-II to type-III band alignment can be realized in the SiC/MoS2 heterostructure by applying a biaxial strain. This heterostructure also shows excellent optical absorption abilities in the visible and far-infrared range, which merits its application as a photocatalyst. The trilayer heterostructure exhibits a tunable Schottky barrier with different stacking patterns and the assembled graphene could act as a protective encapsulating layer on SiC/MoS2. The results show that graphene and MoS2 can tune and improve the electronic performance of SiC and demonstrate the promising application of SiC-based heterostructures for nanoelectronics and nanophotonics.

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