By conducting the orthogonal design for the best mechanical properties of the matrix parts without introducing air pores in advance, the self-ignition coal gangue: lime: cement: gypsum=54: 23: 20: 3 ...accompany with 1.3‰ aluminum powder is determined as the optimal mix proportion of the self-ignition coal gangue aerated concrete. Meanwhile, the reasonable Ca/Si ratio of the elements is found to be 0.82. XRD results show that the hydration products of self-ignition coal gangue autoclaved aerated concrete (SCGAAC) are mainly consisted by CSH gel and tobermorite phase, moreover, SEM approved that a higher Ca/Si ratio is conducive to form the tobermorite phase under the autoclaved conditions. The induced pores in SCGAAC are mainly interconnected open cell structure with middle characteristic latitudinal dimension between 0.5 and 2mm.
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•Ca/Si ratio should be firstly considered when preparing self-ignition coal gangue autoclaved aerated concrete.•W/S ratio and the slurry expansion both significantly affect the microstructure and the mechanical behavior.•Higher Ca/Si ratio is conducive to form towards the tobermorite.
The increasing usage of statins (the 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors) has revealed a number of unexpected beneficial effects, including a reduction in cancer risk.
We ...investigated the direct anticancer effects of different statins approved for clinical use on human breast and brain cancer cells. We also explored the effects of statins on cancer cells using in silico simulations.
In vitro studies showed that cerivastatin, pitavastatin, and fluvastatin were the most potent anti-proliferative, autophagy inducing agents in human cancer cells including stem cell-like primary glioblastoma cell lines. Consistently, pitavastatin was more effective than fluvastatin in inhibiting U87 tumour growth in vivo. Intraperitoneal injection was much better than oral administration in delaying glioblastoma growth. Following statin treatment, tumour cells were rescued by adding mevalonate and geranylgeranyl pyrophosphate. Knockdown of geranylgeranyl pyrophosphate synthetase-1 also induced strong cell autophagy and cell death in vitro and reduced U87 tumour growth in vivo. These data demonstrate that statins main effect is via targeting the mevalonate synthesis pathway in tumour cells.
Our study demonstrates the potent anticancer effects of statins. These safe and well-tolerated drugs need to be further investigated as cancer chemotherapeutics in comprehensive clinical studies.
Temperature-dependent (T-dependent) Raman scattering can provide valuable informations on thermal properties, phonon anharmonicity and electron-phonon coupling of graphene-based materials. Graphene ...are found to exhibit extrinsic T-dependent Raman behavior at low temperature in vacuum or N2 gas, showing a behavior of heavily doped graphene. To obtain intrinsic properties of graphene-based materials, we focused on the comparative T-dependent Raman study on graphite and silicon in the temperature range of 4 K∼1000 K by different excitation lasers and different hot-stages or cryogenic stations. In contrast to the monotonic increase of full width at half maximum (FWHM) with temperature for the Si mode in silicon, FWHM for the G mode in graphite exhibits a minimum when T∼700K, which can be explained by the contributions from phonon anharmonicity and electron-phonon coupling. The result shows that the previous theoretical works underestimate the contribution from phonon anharmonicity above ∼ 600 K. The electron-phonon coupling strength of 0.026 is revealed, smaller than that of graphene. The peak position of G peak of graphite shows a nonlinear decrease with increasing temperature, which agrees well with the previous theoretical calculation. Our results find that the contribution of phonon anharmonicity to both peak position and FWHM is more prominent for the G mode in graphite than the Si mode in silicon.
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In this work, a modified carbon fiber microdisk electrode (CFME) was created via the one-step electrochemical reduction of graphene oxide (GO) in a film on the surface of the electrode. This one-step ...electrochemically reduced GO-modified electrode (ERGO/CFME) displayed improved voltammetric responses to tryptophan (Trp), uric acid (UA), and glutathione (GSH) compared with those afforded by an unmodified CFME. The ERGO/CFME was used as the detector in capillary electrophoresis–electrochemical detection (CE-ECD) to separate and determine these species, and linear concentration ranges of 0.6–600 µmol L
−1
for Trp, 0.8–600 µmol L
−1
for GSH, and 1–600 µmol L
−1
for UA were obtained using this electrode. The detection limits of this system were found to be 0.1 µmol L
−1
for Trp and 0.6 µmol L
−1
for GSH and UA. The ERGO/CFME showed good reproducibility, stability, and durability, and was successfully used to determine Trp, UA, and GSH in human whole-blood extracts. These results demonstrate that ERGO is a promising electrode material for use in electrochemical sensing and CE-ECD.
The temperature-dependent (T-dependent) linewidth (ΓG) and frequency shift (ΔωG) of the G mode provide valuable information on the phonon anharmonicity of graphene-based materials. In contrast to the ...negligible contribution from electron-phonon coupling (EPC) to the linewidth of a Raman mode in semiconductors, ΓG in pristine graphene is dominated by EPC contribution at room temperature due to its semimetallic characteristics. This leads to difficulty in resolving intrinsic contribution from phonon anharmonicity to ΓG. Here, we probed the intrinsic phonon anharmonicity of heavily-doped graphene by T-dependent Raman spectra based on FeCl3-based stage-1 graphite intercalation compound (GIC), in which the EPC contribution is negligible due to the large Fermi level (EF) shift. The ΔωG and ΓG exhibit a nonlinear decrease and noticeable broadening with increasing temperature, respectively, which are both dominated by phonon anharmonicity processes. The contribution of phonon anharmonicity to ΓG of heavily-doped graphene decreases as the EF approaches to the Dirac point. However, the T dependence of ΔωG is almost independent on EF and qualitatively agrees with the theoretical result of pristine graphene. These results provide a deeper understanding of the role of phonon anharmonicity on the Raman spectra of heavily doped graphene.
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For a connected graph
G
with vertex set
V
, let
R
G
{
x, y
} = {
z
∈
V
:
d
G
(
x, z
) ≠
d
G
(
y, z
)} for any distinct
x, y
∈
V
, where
d
G
(
u, w
) denotes the length of a shortest
uw
-path in
G
. ...For a real-valued function
g
defined on
V
, let
g
(
V
) = ∑
s
∈
V
g
(
s
). Let
C
=
{
G
1
,
G
2
,
…
,
G
k
}
be a family of connected graphs having a common vertex set
V
, where
k
≥ 2 and ∣
V
∣≥ 3. A real-valued function
h
:
V
→ 0, 1 is a
simultaneous resolving function
of
C
if
h
(
R
G
{
x, y
}) ≥ 1 for any distinct vertices
x, y
∈
V
and for every graph
G
∈
C
. The
simultaneous fractional dimension
,
Sd
f
(
C
)
, of
C
is min{
h
(
V
):
h
is a simultaneous resolving function of
C
}. In this paper, we initiate the study of the simultaneous fractional dimension of a graph family. We obtain
max
1
≤
i
≤
k
{
dim
f
(
G
i
)
}
≤
Sd
f
(
C
)
≤
min
{
∑
i
=
1
k
dim
f
(
G
i
)
,
|
V
|
2
, where both bounds are sharp. We characterize
C
satisfying
Sd
f
(
C
)
=
1
, examine
C
satisfying
Sd
f
(
C
)
=
|
V
|
2
, and determine
Sd
f
(
C
)
when
C
is a family of vertex-transitive graphs. We also obtain some results on the simultaneous fractional dimension of a graph and its complement.
A vertex set S of a graph G is a dominating set if each vertex of G either belongs to S or is adjacent to a vertex in S. The domination numberγ(G) of G is the minimum cardinality of S as S varies ...over all dominating sets of G. It is known that γ(G)≥13(diam(G)+1), where diam(G) denotes the diameter of G. Define Cr as the largest constant such that γ(G)≥Cr∑1≤i<j≤rd(xi,xj) for any r vertices of an arbitrary connected graph G; then C2=13 in this view. The main result of this paper is that Cr=1r(r−1) for r≥3. It immediately follows that γ(G)≥μ(G)=1n(n−1)W(G), where μ(G) and W(G) are respectively the average distance and the Wiener index of G of order n. As an application of our main result, we prove a conjecture of DeLaViña et al. that γ(G)≥12(eccG(B)+1), where eccG(B) denotes the eccentricity of the boundary of an arbitrary connected graph G.
Volume and composition of saliva are crucial for oral and systemic health. How substances, particularly macromolecules, are transported across the salivary gland epithelium has not been established ...in detail. Tricellulin is a component of tricellular tight junctions that form a central tube to serve as an important route for macromolecule transport. Whether tricellulin is expressed in the submandibular gland (SMG) and involved in salivation has been unknown. Here, by using Western blotting and immunofluorescence, tricellulin was found to be characteristically localized at tricellular contacts of human, rat, and mouse SMGs. Knockdown of tricellulin significantly increased, whereas overexpression of tricellulin decreased, paracellular permeability for 40-kDa but not for 4-kDa fluorescein isothiocyanate–dextran, while transepithelial electrical resistance was unaffected. Conversely, claudin-4 knockdown and overexpression affected transepithelial electrical resistance but not 40-kDa fluorescein isothiocyanate–dextran transport, suggesting that tricellulin regulated transport of macromolecules but not ions, which were mainly regulated by bicellular tight junctions (bTJs). Moreover, tricellulin was dynamically redistributed from tri- to bicellular membranes in cholinergically stimulated SMG tissues and cells. Immunoglobulin-like domain-containing receptor 1 (ILDR1) recruits tricellulin to tricellular contacts. The proportion of macromolecules in the saliva was increased, whereas the amount of stimulated saliva was unchanged in Ildr1-/- mice, which displayed abnormal tricellulin distribution in SMGs. Furthermore, tricellulin interacted with bTJ proteins, such as occludin, claudin-1, claudin-3, claudin-4, and ZO-1, in rat SMG epithelial polarized cell line SMG-C6. Knockdown of tricellulin decreased occludin levels. Thus, we revealed a specific expression pattern of tricellulin in SMG epithelium. Tricellulin not only functioned as a barrier for macromolecules but also modulated the connection of bTJs to the tight junction complex. Alterations in tricellulin expression and distribution could thereby change salivary composition. Our study provided novel insights on salivary gland tight junction organization and function.
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