Perfluorooctanoic acid (PFOA) is a common environmental pollutant that has been associated with various diseases, including cancer. We explored the molecular mechanisms underlying PFOA-induced ...endometrial cancer cell invasion and migration. PFOA treatment enhanced migration and invasion by human Ishikawa endometrial cancer cells, which correlated with decreased E-cadherin expression, a marker of epithelial-mesenchymal transition. PFOA also induced activation of ERK1/2/mTOR signaling. Treatment with rapamycin, an mTOR inhibitor, antagonized the effects of PFOA and reversed the effects of PFOA activation in a xenograft mouse model of endometrial cancer. Consistent with these results, pre-treatment with rapamycin abolished PFOA-induced down-regulation of E-cadherin expression. These results indicate that PFOA is a carcinogen that promotes endometrial cancer cell migration and invasion through activation of ERK/mTOR signaling.
The interaction between C3N4 and three kinds of complex hydrides, LiAlH4, LiBH4, and NaAlH4, was investigated through density functional theory (DFT) computations. The adsorption of LiAlH4, LiBH4, ...and NaAlH4 is much stronger on C3N4 than other traditional carbon materials, such as graphene, carbon nanotubes, and fullerenes. Such strong interaction causes the electron redistribution in complex hydrides, and destabilizes Al/B–H bonds indirectly, thereby reducing the hydrogen removal energy. Moreover, C3N4 provides a very suitable adsorption site for AlHx/BHx (x = 3, 2, 1) units by the bond formation between Al/B and N atoms after losing H atoms. For the first step of dehydrogenation, due to the presence of C3N4, the H-removal energies decrease significantly. In addition, the adsorption energy of H2 molecule on C3N4 is so low that C3N4 would not capture the released H2 from complex hydrides. Therefore, C3N4 is a potential catalyst for H2 release from complex hydrides.
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•C3N4 could significantly reduce the hydrogen removal energy of complex hydrides.•C3N4 would not capture the released H2 molecule from complex hydrides.•C3N4 could provide a very suitable adsorption site for AlHx/BHx (x = 3, 2, 1) units.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Through first-principles computations, we investigated Li
4
NiTeO
6
, which is a new layered Ni-based cathode material for Li ion batteries, by focusing on the sequence of Li removal when it is ...charged. According to our computations, Li
4
NiTeO
6
exhibits satisfactory structural stability with a volume change of 7.2% and electrical conductivity similar to Li
2
MnO
3
. We also examined the electronic configuration of this cathode material during its electrochemical progress and found a weak hybridization of Ni
3d
and O
2p
. Moreover, by analyzing the Bader charges of different elements, we confirmed that O and Ni are exclusively responsible for electron loss and gain. In addition, O evolution reactions occur when half of Li
+
ions are extracted. Finally, we investigated Li
+
migration paths and concluded that migration barriers depend on the charge distribution around migration paths.
The delithiation process of Li
4
NiTeO
6
, which is a layered Ni-based cathode material for Li ion batteries, was computationally investigated.
Through first-principles computations, we investigated Li sub(4)NiTeO sub(6), which is a new layered Ni-based cathode material for Li ion batteries, by focusing on the sequence of Li removal when it ...is charged. According to our computations, Li sub(4)NiTeO sub(6) exhibits satisfactory structural stability with a volume change of 7.2% and electrical conductivity similar to Li sub(2)MnO sub(3). We also examined the electronic configuration of this cathode material during its electrochemical progress and found a weak hybridization of Ni sub(3d) and O sub(2p). Moreover, by analyzing the Bader charges of different elements, we confirmed that O and Ni are exclusively responsible for electron loss and gain. In addition, O evolution reactions occur when half of Li super(+) ions are extracted. Finally, we investigated Li super(+) migration paths and concluded that migration barriers depend on the charge distribution around migration paths.
MXenes, two-dimensional (2D) layered early transition metal carbide, nitride and carbonitride materials, have been prepared by exfoliating MAX phases. In addition to 2D planar MXene, one-dimensional ...tubular forms are also expected to form. Herein, we design atomic models for Sc
2
C monolayers and nanotubes as well as their functionalized counterparts, and investigate their stability and electronic properties through the density functional theory tight-binding method. Dramatic distortion of Sc
2
C and Sc
2
CO
2
tubular structures occurs, while Sc
2
CH
2
and Sc
2
C(OH)
2
nanotubes preserve their tubular morphology upon structural relaxation. Moreover, we reveal that the radii of nanotubes play an important role in the relative stability and band gaps of tubular forms. Sc
2
CH
2
and Sc
2
C(OH)
2
nanotubes are direct-band-gap semiconductors, while the electronic structure of their corresponding planar forms depends on the arrangement of the functional groups.
This work discloses that the electronic properties of MXenes can be controlled by rolling layers into 10 different types of nanotubes.
Membrane technology has been used for hydrogen purification. In this work, two-dimensional g-C sub(3)N sub(3) monolayer was proposed as an effective hydrogen separation membrane on basis of density ...functional theory computations. The structure of g-C sub(3)N sub(3) monolayer was optimized first, and the computed phonon dispersion confirmed its stability and supported the experimental feasibility. The permeability of H sub(2) and impurity gases, including CO, N sub(2) and CH sub(4), was investigated. Compared with H sub(2), it is more difficult for the impurity gases to penetrate through g-C sub(3)N sub(3) monolayer. The high selectivity of H sub(2) vs. CO, N sub(2), and CH sub(4) ensures a superior capability to conventional carbon and silica membranes. With high H sub(2) permeability and selectivity, g-C sub(3)N sub(3) monolayer is a potential H sub(2) purification membrane.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Exploring the dynamic structural evolution of electrocatalysts during reactions represents a fundamental objective in the realm of electrocatalytic mechanism research. In pursuit of this objective, ...we synthesized PhenPtCl
nanosheets, revealing a N
-Pt-Cl
coordination structure through various characterization techniques. Remarkably, the electrocatalytic performance of these PhenPtCl
nanosheets for hydrogen evolution reaction (HER) surpasses that of the commercial Pt/C catalyst across the entire pH range. Furthermore, our discovery of the dynamic coordination changes occurring in the N
-Pt-Cl
active sites during the electrocatalytic process, as clarified through in situ Raman and X-ray photoelectron spectroscopy, is particularly noteworthy. These changes transition from Phen-Pt-Cl
to Phen-Pt-Cl and ultimately to Phen-Pt. The Phen-Pt intermediate plays a pivotal role in the electrocatalytic HER, dynamically coordinating with Cl
ions in the electrolyte. Additionally, the unsaturated, two-coordinated Pt within Phen-Pt provides additional space and electrons to enhance both H
adsorption and H
evolution. This research illuminates the intricate dynamic coordination evolution and structural adaptability of PhenPtCl
nanosheets, firmly establishing them as a promising candidate for efficient and tunable electrocatalysts.
The wide use of computer has led to the reform in modern English teaching approach. Computer concordance, a new multicontext presentation mode, provides a new way for collocation teaching. This study ...explores if there is any difference between on-line concordancer teaching approach, concordance-based explicit teaching approach and traditional deductive approach on college students' collocation use and retention. The findings provide empirical support for concordance-based explicit teaching approach's superiority to other approaches in promoting the immediate use and long-term retention of target collocations, which is measured by immediate and delayed test. Teachers are well-advised to pick up the typical concordance lines deliberately, annotate difficult words when necessary before handing out worksheets to learners.
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