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1.
Nursing ; 54(4): 19-25, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517496

RESUMO

ABSTRACT: This article provides a comprehensive review of Marfan Syndrome (MFS), covering its epidemiology, etiology, clinical presentations, diagnostics, complications, and treatment modalities. The Ghent II Nosology of MFS criteria are crucial in MFS diagnosis, guiding clinicians in identifying high-risk patients. Nursing implications underscore the importance of screenings, assessments, and close follow-ups to optimize the continuum of care for individuals with MFS.


Assuntos
Síndrome de Marfan , Humanos , Síndrome de Marfan/diagnóstico , Síndrome de Marfan/epidemiologia , Síndrome de Marfan/complicações
2.
Nursing ; 54(2): 17-25, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38271124

RESUMO

ABSTRACT: Food allergies are on the rise; the incidence and types of foods implicated have increased worldwide. While peanut allergies are the most well-known, allergies exist to almost all types of foods. This article discusses various types of food allergies along with the most recent prevention and treatment strategies.


Assuntos
Hipersensibilidade Alimentar , Hipersensibilidade a Amendoim , Humanos , Imunoglobulina E , Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/complicações , Hipersensibilidade Alimentar/terapia , Hipersensibilidade a Amendoim/epidemiologia , Hipersensibilidade a Amendoim/prevenção & controle
3.
Nursing ; 54(2): 27-31, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38271126

RESUMO

ABSTRACT: Food intolerances are prevalent and often confused with food allergies. This article reviews the complex landscape of adverse reactions to food, distinguishing between immune-mediated responses (food allergies) and nonimmune reactions (food intolerances). It also explores specific food intolerances such as lactose intolerance, nonceliac gluten sensitivity, fructose intolerance, and salicylate sensitivity.


Assuntos
Hipersensibilidade Alimentar , Intolerância Alimentar , Humanos , Confusão
4.
Nano Lett ; 22(15): 6166-6172, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35912475

RESUMO

Manipulating the exchange bias (EB) effect using an electronic gate is a significant goal in spintronics. The emergence of van der Waals (vdW) magnetic heterostructures has provided improved means to study interlayer magnetic coupling, but to date, these heterostructures have not exhibited electrical gate-controlled EB effects. Here, we report electrically controllable EB effects in a vdW heterostructure, FePS3-Fe5GeTe2. By applying a solid protonic gate, the EB effects were repeatably electrically tuned. The EB field reaches up to 23% of the coercivity and the blocking temperature ranges from 30 to 60 K under various gate-voltages. The proton intercalations not only tune the average magnetic exchange coupling but also change the antiferromagnetic configurations in the FePS3 layer. These result in a dramatic modulation of the total interface exchange coupling and the resultant EB effects. The study is a significant step toward vdW heterostructure-based magnetic logic for future low-energy electronics.

5.
Langmuir ; 38(15): 4633-4644, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35377655

RESUMO

Ionic liquids are versatile solvents that can be tailored through modification of the cation and anion species. Relatively little is known about the corrosive properties of protic ionic liquids. In this study, we have explored the corrosion of both zinc and copper within a series of protic ionic liquids consisting of alkylammonium or alkanolammonium cations paired with nitrate or carboxylate anions along with three aprotic imidazolium ionic liquids for comparison. Electrochemical studies revealed that the presence of either carboxylate anions or alkanolammonium cations tend to induce a cathodic shift in the corrosion potential. The effect in copper was similar in magnitude for both cations and anions, while the anion effect was slightly more pronounced than that of the cation in the case of zinc. For copper, the presence of carboxylate anions or alkanolammonium cations led to a notable decrease in corrosion current, whereas an increase was typically observed for zinc. The ionic liquid-metal surface interactions were further explored for select protic ionic liquids on copper using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) to characterize the interface. From these studies, the oxide species formed on the surface were identified, and copper speciation at the surface linked to ionic liquid and potential dependent surface passivation. Density functional theory and ab initio molecular dynamics simulations revealed that the ethanolammonium cation was more strongly bound to the copper surface than the ethylammonium counterpart. In addition, the nitrate anion was more tightly bound than the formate anion. These likely lead to competing effects on the process of corrosion: the tightly bound cations act as a source of passivation, whereas the tightly bound anions facilitate the electrodissolution of the copper.

6.
Prev Med ; 161: 107132, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35787843

RESUMO

Place and race are two important predictors of fatal police shootings. We used Mapping Police Violence Data and the Washington Post Fatal Force Data to determine whether a county's deprivation status within communities influences the association between the number of fatal police shootings, and how the number of fatal police shootings differs by race and ethnicity. We categorized counties based on the Social Vulnerability Index (SVI) to three categories: low-, medium-, and high-SVI. The analytical sample included 3136 US counties between 2015 and 2020; during this time, 5525 individuals were fatally shot by police. Our findings show that place strongly impacts the number of fatal police shootings. Among all fatal shootings, 713 occurred in low-SVI counties, 1660 in middle-SVI, and 3152 in high-SVI counties. Race played a significant role; fatal shooting deaths increased by 2.3 times among White individuals, 9.6 times among Black individuals, and 15 times among Hispanic individuals between low- and high-SVI counties. The results of negative binomial regressions show a strong association between fatal police shootings and the counties' characteristics. In comparison with low-SVI counties, residents in counties with moderate and high-SVI are more likely to be fatally shot by police by 4.9 and 5.8 percentage points. In addressing violence and fatal police shootings, the vulnerability of counties and the population's racial composition play significant roles and need specific attention in addressing systemic racial disparities in the criminal justice system.


Assuntos
Polícia , Violência , Etnicidade , Humanos , Washington , População Branca
7.
CMAJ ; 194(45): E1529-E1536, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36410749

RESUMO

BACKGROUND: Postmarketing evaluations have linked myocarditis to SARS-CoV-2 mRNA vaccines. We sought to estimate the incidence of myocarditis after mRNA vaccination against SARS-CoV-2, and to compare the incidence with expected rates based on historical background rates in British Columbia. METHODS: We conducted an observational study using population health administrative data from the BC COVID-19 Cohort from Dec. 15, 2020, to Mar. 10, 2022. The primary exposure was any dose of an mRNA vaccine against SARS-CoV-2. The primary outcome was incidence of hospital admission or emergency department visit for myocarditis or myopericarditis within 7 and 21 days postvaccination, calculated as myocarditis rates per 100 000 mRNA vaccine doses, expected rates of myocarditis cases and observedto-expected ratios. We stratified analyses by age, sex, vaccine type and dose number. RESULTS: We observed 99 incident cases of myocarditis within 7 days (0.97 cases per 100 000 vaccine doses; observed v. expected ratio 14.81, 95% confidence interval [CI] 10.83-16.55) and 141 cases within 21 days (1.37 cases per 100 000 vaccine doses; observed v. expected ratio 7.03, 95% CI 5.92-8.29) postvaccination. Cases of myocarditis per 100 000 vaccine doses were higher for people aged 12-17 years (2.64, 95% CI 1.54-4.22) and 18-29 years (2.63, 95% CI 1.94-3.50) than for older age groups, for males compared with females (1.64, 95% CI 1.30-2.04 v. 0.35, 95% CI 0.21-0.55), for those receiving a second dose compared with a third dose (1.90, 95% CI 1.50-2.39 v. 0.76, 95% CI 0.45-1.30) and for those who received the mRNA-1273 (Moderna) vaccine compared with the BNT162b2 (Pfizer-BioNTech) vaccine (1.44, 95% CI 1.06-1.91 v. 0.74, 95% CI 0.56-0.98). The highest observed-to-expected ratio was seen after the second dose among males aged 18-29 years who received the mRNA-1273 vaccine (148.32, 95% CI 95.03-220.69). INTERPRETATION: Although absolute rates of myocarditis were low, vaccine type, age and sex are important factors to consider when strategizing vaccine administration to reduce the risk of postvaccination myocarditis. Our findings support the preferential use of the BNT162b2 vaccine over the mRNA-1273 vaccine for people aged 18-29 years.


Assuntos
COVID-19 , Miocardite , Masculino , Feminino , Humanos , Idoso , Vacinas contra COVID-19/efeitos adversos , Estudos de Coortes , SARS-CoV-2 , Miocardite/epidemiologia , Miocardite/etiologia , Vacina de mRNA-1273 contra 2019-nCoV , Vacina BNT162 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinação/efeitos adversos , Vacinas de mRNA
8.
Nanotechnology ; 34(6)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36343357

RESUMO

Two-dimensional (2D) ferroelectric materials are providing promising platforms for creating future nano- and opto-electronics. Here we propose new hybrid van der Waals heterostructures, in which the 2D ferroelectric material CuInP2S6(CIPS) is layered on a 2D semiconductor for near-infrared (NIR) memory device applications. Using density functional theory, we show that the band gap of the hybrid bilayers formed with CIPS can be tuned and that the optical and electronic properties can be successfully modulated via ferroelectric switching. Of the 3712 heterostructures considered, we identified 19 structures that have a type II band alignment and commensurate lattice matches. Of this set, both the CuInP2S6/PbSe and CuInP2S6/Ge2H2heterostructures possess absorption peaks in the NIR region that change position and intensity with switching polarisation, making them suitable for NIR memory devices. The CuInP2S6/ISSb, CuInP2S6/ISbSe, CuInP2S6/ClSbSe and CuInP2S6/ZnI2heterostructures had band gaps which can be switched from direct to indirect with changing the polarisation of CIPS making them suitable for optoelectronics and sensors. The heterostructures formed with CIPS are exciting candidates for stable ferroelectric devices, opening a pathway for tuning the band alignment of van der Waal heterostructures and the creation of modern memory applications that use less energy.

9.
Chemistry ; 27(50): 12826-12834, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34272779

RESUMO

Boronium cation-based ionic liquids (ILs) have demonstrated high thermal stability and a >5.8 V electrochemical stability window. Additionally, IL-based electrolytes containing the salt LiTFSI have shown stable cycling against the Li metal anode, the "Holy grail" of rechargeable lithium batteries. However, the basic spectroscopic characterisation needed for further development and effective application is missing for these promising ILs and electrolytes. In this work, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and density functional theory (DFT) calculations are used in combination to characterise four ILs and electrolytes based on the [NNBH2 ]+ and [(TMEDA)BH2 ]+ boronium cations and the [FSI]- and [TFSI]- anions. By using this combined experimental and computational approach, proper understanding of the role of different ion-ion interactions for the Li cation coordination environment in the electrolytes was achieved. Furthermore, the calculated vibrational frequencies assisted in the proper mode assignments for the ILs and in providing insights into the spectroscopic features expected at the interface created when they are adsorbed on a Li(001) surface. A reproducible synthesis procedure for [(TMEDA)BH2 ]+ is also reported. The fundamental findings presented in this work are beneficial for any future studies that utilise IL based electrolytes in next generation Li metal batteries.

10.
Nanotechnology ; 33(2)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34610590

RESUMO

Graphitic nanoplatelets (GNPs) have been treated using an ultrasonicated ozonolysis procedure to produce stable aqueous dispersions that facilitate deposition of thin films using electrophoretic deposition. The thin GNP films were then coated with zero valence (ZV) iron nanocubes using a pulsed electrodeposition technique. Characterization of the ZV-iron coating with deposition time revealed that the changing magnetic character of the ferromagnetic-graphitic hybrid material was related to the nucleation density and growth of the ZV-iron nanocubes. Density functional theory calculations show a preference for ZV-iron adsorption at the oxygen sites of the GNPs, with ZV-iron displacement of oxygen groups favored in some configurations. Transmission electron microscopy studies confirm ZV-iron growth nucleates preferentially at the graphite nanoplatelet edges and the hybrid material magnetism is affected by the convergent crystalline grain boundaries formed between adjacent ZV-iron nanocubes.

11.
Langmuir ; 36(13): 3425-3438, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32163292

RESUMO

Boron nitride nanotubes (BNNTs) represent a relatively new class of materials that provides alternative electrical and thermal properties to the carbon analogue. The high chemical and thermal stability and large band gap combined with high electrical resistance make BNNTs desirable in several thin-film applications. In this study, stable BNNT and hexagonal boron nitride (hBN) particle dispersions have been developed using environmentally friendly advanced oxidation processing (AOP) that can be further modified for electrophoretic deposition (EPD) to produce thin films. The characterization of the dispersions has revealed how the hydroxyl radicals produced in AOP react with BNNT/hBN and contaminant boron nanoparticles (BNPs). While the radicals remove the carbon contaminant present on BNNT/hBN and increase dispersion stability, they also oxidize the BNPs and the boron oxide produced, which, conversely, reduces the dispersion stability. The use of high- or low-powered ultrasonication in combination with the AOP affects the rate of the competing reactions, with low-powered sonication and AOP providing the best combination for producing stable dispersions with high concentrations. BNNT/hBN dispersions were functionalized with polyethyleneimine to facilitate EPD, where films of several micrometer thickness were readily deposited onto stainless steel and glass-fiber fabrics. BNNT/hBN films produced on glass fabrics by EPD exhibited a consistent through-thickness macroporosity that was facilitated by platelet and nanotube stacking. The film macroporosity present on the coated fabrics was suitable for use as separator layers in supercapacitors and provided improved device robustness with a minimal impact on electrochemical performance.

12.
Phys Chem Chem Phys ; 21(13): 7165-7173, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30887979

RESUMO

Silicene, the silicon analog of graphene, is an atomically thin two-dimensional material with promising applications in gas sensing, storage and as components in modern electronic devices. Silicene epitaxially grown on the Ag(111) surface can expand the utility of the silver surface by enabling the tuning of its work function through the functionalisation of silicene. Here we examine the electronic and structural properties and the thermodynamic stability of functionalised silicene/4 × 4 Ag(111) using density functional theory calculations coupled with ab initio molecular dynamics (AIMD) simulations. We focus on 11 functional groups, namely phenyl, methyl, hydroxyl, cyano, methoxyl, amino and ethylmethylamine, in addition to 4 halogen atoms. These functional groups are shown to endow the Si/Ag(111) surface with a large variation in the work function. Our AIMD simulations confirm the thermodynamic stability of these 11 functionalised structures. This work shows the possibility of tuning the electronic structure of silicene by functionalisation, which could then be utilized in polymer solar cells and nanoelectronic circuit components.

13.
Phys Chem Chem Phys ; 21(19): 10028-10037, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31044201

RESUMO

The electrode cyclability of high energy density Li-metal batteries can be significantly improved with the use of ionic liquid (IL) based electrolytes, which can ameliorate device issues through the suppression of dendrite initiation and propagation. This enhancement is often attributed to the formation of a stable solid electrolyte interphase (SEI) layer between the electrode and the electrolyte. In this paper, we have modelled the adsorption of the IL ethylammonium tetrafluoroborate [EtNH3+][BF4-] on a Li(001) surface, using density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) simulations to capture the initial stages of the SEI layer formation, and gain a greater insight into the stability of [EtNH3+][BF4-] on a lithium surface. Eleven unique minimum energy structures of the [EtNH3+][BF4-] pair adsorbed on the Li(001) surface were found, having binding energies between -1.80 eV to -1.58 eV. The interface between the electrolyte molecules and electrode surface were stabilized by the formation of Li-F bonds between the anion and Li surface leading to formation of Lix-BF4 clusters, where x = 2-4. This was accompanied by a transfer of charge from the lithium surface to the cation and anion. The thermal stability of the IL was investigated via AIMD simulations, and the IL was found not to spontaneously dissociate on the surface at room temperature or at an elevated temperature of 157 °C within the examined simulation time of 4.64 ps, with Lix-BF4 clusters forming early into the simulations (<1 ps). These findings provide useful information for future development of Li-metal batteries.

14.
Phys Chem Chem Phys ; 21(32): 17521-17537, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31198924

RESUMO

Silicene is a two-dimensional nanomaterial, composed of Si atoms arranged into a buckled honeycomb network. It has become of great interest in recent years due to its remarkable properties such as its natural compatibility with current silicon-based technology. Due to its extreme thinness on the nanoscale, and large lateral dimensions, it has potential applications in gas sensing, gas storage and components in modern electronic devices. In this work, density functional theory calculations and ab initio molecular dynamics simulations are used to examine the reaction of SO2, NO2 and H2S on the Si/Ag(111) surface. It was shown that each gas will adsorb on the surface in different orientations and adsorption sites. SO2 and NO2 were found to chemisorb on the surface, whereas H2S was found to physisorb. SO2 and H2S adsorb associatively, whereas NO2 readily dissociates, producing adsorbed oxygen, and gaseous NO. At elevated temperatures, the SO2 and NO2 remain strongly bound to the surface, resulting in poisoning of the silicene, while H2S readily desorbs. Ab initio molecular dynamics also show that NO2 will selectively bind before SO2 when both gases are present in the same environment. This work shows that Si/Ag(111) may provide useful properties for gas sensing and storage applications.

15.
Sci Technol Adv Mater ; 19(1): 76-100, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29410713

RESUMO

Mono-elemental two-dimensional (2D) crystals (graphene, silicene, germanene, stanene, and so on), termed 2D-Xenes, have been brought to the forefront of scientific research. The stability and electronic properties of 2D-Xenes are main challenges in developing practical devices. Therefore, in this review, we focus on 2D free-standing group-IV graphene analogs (graphene quantum dots, silicane, and germanane) and the functionalization of these sheets with organic moieties, which could be handled under ambient conditions. We highlight the present results and future opportunities, functions and applications, and novel device concepts.

16.
J Chem Phys ; 144(11): 114704, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-27004890

RESUMO

Silicene is a relatively new material consisting of a two-dimensional sheet of silicon atoms. Functionalisation of silicene with different chemical groups has been suggested as a way to tune its electronic properties. In this work, density functional theory calculations and ab initio molecular dynamics simulations are used to examine the effects of functionalisation with naphthyl or anthracyl groups, which are two examples of small polycyclic aromatic hydrocarbons (PAHs). Different attachment positions on the naphthyl and anthracyl groups were compared, as well as different thicknesses of the silicene nanosheet. It was found that the carbon attachment position farthest from the bond fusing the aromatic rings gave the more stable structures for both functional groups. All structures showed direct band gaps, with tuning of the band gap being achievable by increasing the length of the PAH or the thickness of the silicene. Hence, modifying the functional group or thickness of the silicene can both be used to alter the electronic properties of silicene making it a highly promising material for use in future electronic devices and sensors.

17.
Phys Chem Chem Phys ; 17(41): 27683-9, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26427933

RESUMO

Zinc blende (ZB) ZnO has gained increasing research interest due to its favorable properties and its stabilization on the nanoscale. While surface properties are important on the nanoscale, the studies on ZB ZnO surface properties are rare. Here we have performed first principles calculations of the energies and structures of ZB and wurtzite (WZ) ZnO surfaces. Our results indicate that, among the four surfaces parallel to the polar axes, such as (101̄0) and (112̄0) of the WZ phase and (110) and (211) of the ZB phase, the polar (211) surface has substantially lower surface vacancy formation energies than the others, which makes ZB ZnO promising for catalytic applications. Our results also imply that the stabilization of ZB ZnO on the nanoscale is due to some mechanisms other than surface energies.

18.
Phys Chem Chem Phys ; 16(40): 22139-44, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25212731

RESUMO

The calculation of the accurate surface energies for (0001) surfaces of wurtzite ZnO is difficult because it is impossible to decouple the two inequivalent (0001)-Zn and (0001¯)-O surfaces. By using a heterojunction model we have transformed the uncertainty of the surface energies into that of interface energies which is much smaller than the former and hence estimated the surface energies to a high degree of accuracy. It is found that the oxygen terminated (0001¯)-O face of the wurtzite phase and (1¯1¯1¯O of the zinc blende phase are more stable than their Zn-terminated counterparts within the major temperature and oxygen partial pressure range accessible to experiment. The instability of Zn-terminated polar surfaces explains the experimentally observed high activity of these surfaces. The effects of native surface vacancies on the surface energies have also been discussed. These results provide insights into the modification of the surface stability and activity of ZnO nanoparticles.

20.
ACS Appl Mater Interfaces ; 16(21): 26967-26983, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38747623

RESUMO

As lithium-ion (Li-ion) batteries approach their theoretical limits, alternative energy storage systems that can power technology with greater energy demands must be realized. Li-metal batteries, particularly Li-air batteries (LABs), are considered a promising energy storage candidate due to their inherent lightweight and energy-dense properties. Unfortunately, LAB practicality remains hindered by inadequate oxygen solubility and diffusion rates within the electrolyte, both which are fundamental for LAB operation. Due to exceptionally high oxygen solubilities, perfluorochemicals (PFCs) have been investigated as a promising solution to this issue. Although PFCs have been reported to enhance LAB performance and longevity when implemented within the cathodic regions of LABs in several studies, the influence of this class of compounds on other components of the battery (including the anode and the electrolyte) is also highly important. This paper reviews the use of PFCs in LABs to date and discusses the performance enhancements resulting from their implementation. We identify and discuss future prospects and emerging research directions for the use of PFCs into LAB design, in the effort toward realization of high-performing LAB technologies.

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