Significant efforts have been devoted to investigating the oxidation of MXenes in various environments. However, the underlying mechanism of MXene oxidation and its dependence on the electrode potential remain poorly understood. Here we show the oxidation behavior of MXenes under the working conditions of electrochemical processes in terms of kinetics and thermodynamics by using constant-potential ab initio simulations.
View Article and Find Full Text PDFThe two-dimensional (2D) metallic phase of MoS, 1T-MoS, has extraordinary electrical conductivity in contrast to the common 2D semiconducting phase, 2H-MoS. However, the thermodynamic instabilities of 1T-MoS hinder its application. In this work, we investigate the possibilities of stabilizing 1T-MoS through heterostructure design using first-principles calculations.
View Article and Find Full Text PDFMXenes are 2D materials with great potential in various applications. However, the degradation of MXenes in humid environments has become a main obstacle in their practical use. Here we combine deep neural networks and an active learning scheme to develop a neural network potential (NNP) for aqueous MXene systems with ab initio precision but low cost.
View Article and Find Full Text PDFHeterogeneous catalysts consisting of supported metallic nanoparticles typically derive exceptional catalytic activity from their large proportion of undercoordinated surface sites which promote adsorption of reactant molecules. Simultaneously, these high energy surface configurations are unstable, leading to nanoparticle growth or degradation and eventually a loss of catalytic activity. Surface morphology of catalytic nanoparticles is paramount to catalytic activity, selectivity, and degradation rates, however it is well-known that harsh reaction conditions can cause the surface structure to change.
View Article and Find Full Text PDFJ Stroke Cerebrovasc Dis
October 2022
Objective: There is a low incidence of the medullary infarctions and sparse data about the vascular territories, as well as a correlation among the anatomic, magnetic resonance imaging (MRI) and neurologic signs.
Materials And Methods: Arteries of the 10 right and left sides of the brain stem were injected with India ink, fixed in formalin and microdissected. The enrolled 34 patients with medullary infarctions underwent a neurologic, MRI and Doppler examination.
The addition of iron (Fe) can in certain cases have a strong positive effect on the activity of cobalt and nickel oxide nanoparticles in the electrocatalytic oxygen evolution reaction (OER). The reported optimal Fe dopant concentrations are, however, inconsistent, and the origin of the increased activity due to Fe dopants in mixed oxides has not been identified so far. Here, we combine density functional theory calculations, scanning tunneling microscopy, and OER activity measurements on atomically defined Fe-doped Co oxyhydroxide nanoparticles supported on a gold surface to establish the link between the activity and the Fe distribution and concentration within the oxyhydroxide phase.
View Article and Find Full Text PDFThe activity-stability conundrum has long been the Achilles' heel in the design of catalysts, in particular, for electrochemical reactions such as water splitting. Here, we use ab initio thermodynamics to delineate the surface stoichiometry of a group of perovskite oxides with different activities towards the oxygen evolution reaction (OER), in order to get a measure of their stability under OER operating conditions. In particular, we compare the surface stability of SrIrO, SrRuO and SrTiO, establishing atomistic insights into the stability and dissolution of these oxide surfaces.
View Article and Find Full Text PDFThe development of highly efficient and durable earth-abundant hydrogen evolution reaction (HER) catalysts is crucial for the extensive implementation of the hydrogen economy. Members of the 2D MXenes family, particularly MoCT, have recently been identified as promising HER catalysts. However, their inherent oxidative instability in air and aqueous electrolyte solutions is hindering their widespread use.
View Article and Find Full Text PDFAdding a two-dimensional (2D) overlayer on a metal surface is a promising route for activating reactants confined in the interfacial space. However, an atomistic understanding of the role played by undercoordinated sites of the 2D overlayer in the activation of molecules in this nanoscaled confined space is yet to be developed. In this paper, we study CO dissociation as a prototypical reaction to investigate CO activation in the confined space enclosed by Rh(111) and a monolayer of hexagonal boron nitride (-BN).
View Article and Find Full Text PDFNumerous redox transformations that are essential to life are catalyzed by metalloenzymes that feature Earth-abundant metals. In contrast, platinum-group metals have been the cornerstone of many industrial catalytic reactions for decades, providing high activity, thermal stability, and tolerance to chemical poisons. We assert that nature's blueprint provides the fundamental principles for vastly expanding the use of abundant metals in catalysis.
View Article and Find Full Text PDFBackground: Pruritus is the most common complaint encountered in dermatological practice. It is estimated that up to 4% of the world population suffers from chronic itch. Chronic pruritus can be associated with both cutaneous or systemic conditions.
View Article and Find Full Text PDFVitiligo is a relatively common disorder characterized by areas of depigmented skin. It may be associated with social stigma and adversely affects the quality of life. Although many treatment options are available, none is curable.
View Article and Find Full Text PDFBackground: Cosmetic surgery and esthetic procedures have become a billion dollar industry owing to the ever-growing demand of the population to stay young. The injectable treatments including fillers and botulinum toxin have become highly popular because of their quick, predictable and lasting results in the management of facial wrinkles and rejuvenation. Although these treatment modalities are relatively safe, they are associated with certain side effects.
View Article and Find Full Text PDFAim: In this paper, using a mathematical model, we will show that for special exchanged photons, the Hamiltonian of a collection of neurons tends to a constant number and all activities is stopped. These photons could be called as the dead photons. To this aim, we use concepts of Bio-BIon in Izhikevich Neuron model.
View Article and Find Full Text PDFOpen Access Maced J Med Sci
September 2019
As indicated by the latest scientific evidence, the lines between different fields of medicine gradually blur and overlap more and more. Psychiatry and dermatology have seen this trend in the last decade as an ever-increasing number of studies suggest the strong connection of many dermatological syndromes and diseases with psychiatric conditions and vice versa. It seems that the relationship is more intertwined than previously believed and the effects of different multidisciplinary approaches to diagnostic and treatment are being considered.
View Article and Find Full Text PDFOpen Access Maced J Med Sci
September 2019
Aim: In this paper, inspiring Darwin's theory, we propose a model which connects evolutions of neural circuits with evolutions of cosmos. In this model, in the beginning, there are some closed strings which decay into two groups of open strings.
Methods: First group couple to our universe from one side and produce matters like some genes of DNAs and couple to an anti-universe from another side with opposite sign and create anti-matters like some anti-genes of anti-DNAs.
Understanding the mechanisms of cancer immune-tolerance is one of the most important challenges. Several studies have demonstrated the potential anticarcinogenic effects of beta-blockers, in patients with prostate cancer, breast cancer, and melanoma. At the other side variety of dermatoses may be caused or aggravated by β-blockers-psoriasis, lichen planus-like drug eruptions (LDE), acrocyanosis, alopecia etc.
View Article and Find Full Text PDFOpen Access Maced J Med Sci
September 2019
Recently, some new methods for sexing of chicken eggs by fluorescence and Raman spectroscopy through the shell membrane have been proposed. On the other hand, in another investigation, a new virus medical imaging has been suggested. In this research, summing over these considerations, a new technique for sexing of chicken eggs by virus spectroscopy through the shell membrane is proposed.
View Article and Find Full Text PDFOpen Access Maced J Med Sci
September 2019
Insomnia means difficulty in falling asleep and/or stays asleep. Insomnia commonly leads to daytime sleepiness, lethargy, and a general feeling of being unwell. The most common treatment of insomnia includes GABAA receptor positive allosteric modulators or Melatonin agonists.
View Article and Find Full Text PDFOpen Access Maced J Med Sci
September 2019
Aim: In this research, we show that DNA waves have many applications in biology. DNA is formed by the joining of quantum particles like electrons and charged atoms. DNA has different motions during transcription, translation, and replication, in which the charged particles move, accelerate, and emit waves.
View Article and Find Full Text PDFBackground: Anetodermas are rare disorders of connective tissue with a focal loss of elastic fibres in the upper and mid dermis. Two types are separated, inflammatory and non-inflammatory.
Case Reports: We report two cases of acquired anetoderma Schweniger-Buzzi type.
Open Access Maced J Med Sci
September 2019
The main surgical treatment for melanoma consists in wide surgical excision of the primary lesion and the sentinel node but in recent times management of melanoma is rapidly evolving with the introduction of new systemic therapies, like BRAF inhibitors, MEK inhibitors and antibodies anti-PD-1 that show good results in controlling even advanced stages of the disease. This review aims to present data for the optimal surgical management of patients with malignant melanoma.
View Article and Find Full Text PDFOpen Access Maced J Med Sci
September 2019
To recover chick embryos damaged the brain, two methods are presented. In both of them, somatic cells of an embryo introduced into an egg cell and an embryo have emerged. In one method, injured a part of the brain in the head of an embryo is replaced with a healthy part of the brain.
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