A new approach to prepare heterometallic cluster organic frameworks has been developed. The method was employed to link Anderson‐type polyoxometalate (POM) clusters and transition‐metal clusters by ...using a designed rigid tris(alkoxo) ligand containing a pyridyl group to form a three‐fold interpenetrated anionic diamondoid structure and a 2D anionic layer, respectively. This technique facilitates the integration of the unique inherent properties of Anderson‐type POM clusters and cuprous iodide clusters into one cluster organic framework.
All linked up: Two unprecedented heterometallic cluster organic frameworks were constructed through directly linking Anderson‐type polyoxometalate (POM) clusters with different cuprous iodide clusters by using a rigid bifunctional tris(alkoxo) ligand under solvothermal conditions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Humic substances (HS) as representative natural organic matters and the most common organic compounds existing in the environment, has been applied to the treatment and remediation of environmental ...pollution. This review systematically introduces and summarizes the redox activity of HS for the remediation of environmental pollutants. For inorganic pollutants (such as silver, chromium, mercury, and arsenic), the redox reaction of HS can reduce their toxicity and mobilization, thereby reducing the harm of these pollutants to the environment. The concentration and chemical composition of HS, environmental pH, ionic strength, and competing components affect the degree and rate of redox reactions between inorganic pollutants and HS significantly. With regards to organic pollutants, HS has photocatalytic activity and produces a large number of reactive oxygen species (ROS) under the light which reacts with organic pollutants to accelerate the degradation of organic pollutants. Under the affection of HS, the redox of Fe(III) and Fe(II) can enhance the efficiency of Fenton-like reaction to degrade organic pollutants. Finally, the research direction of HS redox remediation of environmental pollution is prospected.
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•The redox activity of humic substances for environmental remediation is reviewed.•The redox mechanism of humic substances and environmental pollutants is discussed.•The factors affecting the oxidation-reduction rate of humic substances are described.•The future perspectives and challenges of humic substances in the application of environmental remediation are pointed out.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
3.
Cubic Polyoxometalate−Organic Molecular Cage Zheng, Shou-Tian; Zhang, Jie; Li, Xin-Xiong ...
Journal of the American Chemical Society,
11/2010, Volume:
132, Issue:
43
Journal Article
Peer reviewed
Tris(hydroxymethyl)aminomethane (Tris) was successfully grafted onto the surface of a Ni6-substituted polyoxotungstate formed in situ to further generate a three-connected polyoxometalate building ...block. The cooperative assembly of Tris functionalized three-connected building blocks and rigid 1,3,5-benzenetricarboxylate gave rise to an unprecedented cubic polyoxometalate−organic molecular cage with high thermal and hydrothermal stability.
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IJS, KILJ, NUK, PNG, UL, UM
Hydrothermal humification technology for the preparation of artificial humic matters provides a new strategy, greatly promoting the natural maturation process. Iron, as a common metal, is widely used ...in the conversion of waste biomass; however, the influence of Fe3+ on hydrothermal humification remains unknown. In this study, FeCl3 is used to catalyze the hydrothermal humification of corn straw, and the influence of Fe3+ on the hydrothermal humification is explored by a series of characterization techniques. Results show that Fe3+ as the catalyst can promote the decomposition of corn straw, shorten the reaction time from 24 h to 6 h, and increase the yield from 6.77 % to 14.08 %. However, artificial humic acid (A‐HA) obtained from Fe3+‐catalysis hydrothermal humification contains more unstable carbon and low amount of aromatics, resulting in a significantly decreased stability of the artificial humic acid. These results provide theoretical guidance for regulating the structure and properties of artificial humic acid to meet various maintenance needs.
Fe3+‐catalysis hydrothermal humification shortens the reaction time and increases the yield, but the obtained artificial humic acid contains more unstable carbon and lower amount of aromatic compounds, resulting in a significantly decreases stability of the artificial humic acid.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor due to the lack of effective therapeutic drugs. Cancer therapy targeting programmed cell death protein 1 (PD-1) or programmed ...death ligand-1 (PD-L1) is of revolutionary. However, the role of intrinsic PD-L1, which determines immune-therapy outcomes, remains largely unclear. Here we demonstrated an oncogenic role of PD-L1 via binding and activating Ras in GBM cells. RNA-sequencing transcriptome data revealed that PD-L1 significantly altered gene expression enriched in cell growth/migration/invasion pathways in human GBM cells. PD-L1 overexpression and knockout or knockdown demonstrated that PD-L1 promoted GBM cell proliferation and migration in vitro and in vivo. Mechanistically, PD-L1 prominently activated epithelial mesenchymal transition (EMT) process in a MEK/Erk- but not PI3K/Akt-dependent manner. Further, we identified intracellular interactions of PD-L1 and H-Ras, which led to Ras/Erk/EMT activation. Finally, we demonstrated that PD-L1 overexpression promoted while knockdown abolished GBM development and invasion in orthotopic GBM models of rodents. Taken together, we found that intracellular PD-L1 confers GBM cell malignancy and aggressiveness via binding Ras and activating the downstream Erk-EMT signaling. Thus, these results shed important insights in improving efficacy of immune therapy for GBM as well as other malignant tumors.
•PD-L1 overexpression promoted while knockdown abolished orthotopic glioma growth.•PD-L1 promoted GBM migration in vivo and in vitro and facilitates epithelial mesenchymal transition.•This facilitation effect is dependent on MEK/Erk but not on PI3K/Akt signaling.•PD-L1 increases Ras activity by Ras binding to activate Ras/Erk/EMT axis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
An oxalate-assisted lanthanide (Ln) incorporation strategy is first demonstrated for creating rare high-nuclearity Ln-containing polyoxoniobates (PONbs). With the strategy, a series of ...high-nuclearity Ln-containing PONbs of 50-nuclearity Dy 2 Nb 48 , 103-nuclearity Dy 7 Nb 96 , 200-nuclearity Dy 10 Nb 190 , and 206-nuclearity Dy 14 Nb 192 have been made, showing an increasingly large structure evolution from Dy 2 Nb 48 monomer to Dy 7 Nb 96 dimer and to distinct Dy 10 Nb 190 and Dy 14 Nb 192 tetramers. Among them, Dy 14 Nb 192 presents the largest heterometallic PONb and also the PONb with the greatest number of Ln ions reported thus far. Interestingly, both giant Dy 14 Nb 192 and Dy 10 Nb 190 molecules can further undergo single-crystal to single-crystal intermolecular aggregations, forming infinite {Dy 14 Nb 192 }∞ and {Dy 10 Nb 190 }∞ chains, respectively. The former structural transformation shows a reversible humidity-dependent aggregation–disaggregation process accompanied by a proton conductivity response, while the latter structural transformation is irreversible. These new species largely enrich the very limited members of Ln-containing PONb family and offer rare examples for studying structural transformations between giant molecular aggregates and infinitely extended structures at the atomic level.
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IJS, KILJ, NUK, PNG, UL, UM
In the hexaploid wheat genome, there are three Gα genes, three Gβ and twelve Gγ genes, but the function of Gβ in wheat has not been explored. In this study, we obtained the overexpression of
...Arabidopsis plants through inflorescence infection, and the overexpression of wheat lines was obtained by gene bombardment. The results showed that under drought and NaCl treatment, the survival rate of Arabidopsis seedlings' overexpression of
was higher than that of the wild type, while the survival rate of the related mutant
was lower than that of the wild type. The survival rate of wheat seedlings with
overexpression was higher than that of the control. In addition, under drought and salt stress, the levels of superoxide dismutase (SOD) and proline (Pro) in the wheat overexpression of
were higher than that of the control, and the concentration of malondialdehyde (MDA) was lower than that of the control. This indicates that
could improve the drought resistance and salt tolerance of Arabidopsis and wheat by scavenging active oxygen. Overall, this work provides a theoretical basis for wheat G-protein β-subunits in a further study, and new genetic resources for the cultivation of drought-tolerant and salt-tolerant wheat varieties.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Hydrothermal humification technology for the preparation of artificial humic matters provides a new strategy, greatly promoting the natural maturation process. Iron, as a common metal, is widely used ...in the conversion of waste biomass; however, the influence of Fe
on hydrothermal humification remains unknown. In this study, FeCl
is used to catalyze the hydrothermal humification of corn straw, and the influence of Fe
on the hydrothermal humification is explored by a series of characterization techniques. Results show that Fe
as the catalyst can promote the decomposition of corn straw, shorten the reaction time from 24 h to 6 h, and increase the yield from 6.77 % to 14.08 %. However, artificial humic acid (A-HA) obtained from Fe
-catalysis hydrothermal humification contains more unstable carbon and low amount of aromatics, resulting in a significantly decreased stability of the artificial humic acid. These results provide theoretical guidance for regulating the structure and properties of artificial humic acid to meet various maintenance needs.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The hominin record from southern Asia for the early Late Pleistocene epoch is scarce. Well-dated and well-preserved fossils older than ∼45,000 years that can be unequivocally attributed to Homo ...sapiens are lacking. Here we present evidence from the newly excavated Fuyan Cave in Daoxian (southern China). This site has provided 47 human teeth dated to more than 80,000 years old, and with an inferred maximum age of 120,000 years. The morphological and metric assessment of this sample supports its unequivocal assignment to H. sapiens. The Daoxian sample is more derived than any other anatomically modern humans, resembling middle-to-late Late Pleistocene specimens and even contemporary humans. Our study shows that fully modern morphologies were present in southern China 30,000-70,000 years earlier than in the Levant and Europe. Our data fill a chronological and geographical gap that is relevant for understanding when H. sapiens first appeared in southern Asia. The Daoxian teeth also support the hypothesis that during the same period, southern China was inhabited by more derived populations than central and northern China. This evidence is important for the study of dispersal routes of modern humans. Finally, our results are relevant to exploring the reasons for the relatively late entry of H. sapiens into Europe. Some studies have investigated how the competition with H. sapiens may have caused Neanderthals' extinction (see ref. 8 and references therein). Notably, although fully modern humans were already present in southern China at least as early as ∼80,000 years ago, there is no evidence that they entered Europe before ∼45,000 years ago. This could indicate that H. neanderthalensis was indeed an additional ecological barrier for modern humans, who could only enter Europe when the demise of Neanderthals had already started.
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DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Two isostructural Co(Cd)-antimony-oxo tartrate cluster-based compounds with a one-dimensional (1-D) belt-like structure, namely H
9.2
Co(H
2
O)
6
{
M
0.5
(H
2
O)
3.5
{
M
′(H
2
O)
4
Sb
V
O
6
Co
4.2
(H
...2
O)
5
Sb
III
6
(μ
3
-O)
2
(tta)
6
}}
2
·
n
H
2
O (
M
= Co,
M
′ = Co,
n
= 9 (
1
);
M
= Cd
0.39
/Co
0.61
,
M
′ = Cd
0.24
/Co
0.76
,
n
= 7 (
2
); H
4
tta = tartaric acid), have been synthesized by solvothermal methods. It is noteworthy that the relatively rare mixed-valence Sb(
iii
,
v
) exists in the structures. The anionic clusters in both compounds appear to be in a sandwich configuration; the top and bottom layers are based on {Sb
3
(μ
3
-O)(tta)
3
} brackets, and the intermediate layer is occupied by {Sb
V
O
6
Co
4.2
(H
2
O)
5
}. The title compounds have been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analyses, thermogravimetric analyses, and UV-Vis spectroscopy. We chose compound
2
as a representative to test its proton conductivity, and the results show that the conductivity can reach 1.42 × 10
−3
S cm
−1
at 85 °C under 98% relative humidity.
Isostructural mixed-valence compounds H
9.2
Co(H
2
O)
6
{
M
0.5
(H
2
O)
3.5
{
M
'(H
2
O)
4
Sb
V
O
6
Co
4.2
(H
2
O)
5
Sb
III
6
(μ
3
-O)
2
(tta)
6
}}
2
·
n
H
2
O (
M
= Co,
M
' = Co,
n
= 9 (
1
);
M
= Cd
0.39
/Co
0.61
,
M
' = Cd
0.24
/Co
0.76
,
n
= 7 (
2
)) were synthesized. The proton conductivity of
2
is 1.42 × 10
−3
S·cm
−1
at 85 °C and 98% RH.
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