Let X be a separated scheme of dimension d of finite type over a perfect field k of positive characteristic p. In this work, we show that Bloch’s cycle complex \mathbb {Z}^c_X of zero cycles mod p^n ...is quasi-isomorphic to the Cartier operator fixed part of a certain dualizing complex from coherent duality theory. From this we obtain new vanishing results for the higher Chow groups of zero cycles with mod p^n coefficients for singular varieties.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
α-mangostin has been confirmed to promote the apoptosis of MG-63 cells, but its specific pro-apoptosis mechanism in osteosarcoma (OS) remains further investigation. Here, we demonstrated that ...α-mangostin restrained the viability of OS cells (143B and Saos-2), but had little effect on the growth of normal human osteoblast. α-mangostin increased OS cell apoptosis by activating the caspase-3/8 cascade. Besides, α-mangostin induced endoplasmic reticulum (ER) stress and restrained the Wnt/β-catenin pathway activity. 4PBA (an ER stress inhibitor) or LiCl (an effective Wnt activator) treatment effectively hindered α-mangostin-induced apoptosis and the caspase-3/8 cascade. Furthermore, we also found that α-mangostin induced ER stress by promoting ROS production. And ER stress-mediated apoptosis caused by ROS accumulation depended on the inactivation of Wnt/β-catenin pathway. In addition, α-mangostin significantly hindered the growth of xenograft tumors, induced the expression of ER stress marker proteins and activation of the caspase-3/8 cascade, and restrained the Wnt/β-catenin signaling in vivo. In short, ROS-mediated ER stress was involved in α-mangostin triggered apoptosis, which might depended on Wnt/β-catenin signaling inactivation.
The in situ exsolution technique of nanoparticles has brought new opportunities for the utilization of perovskite‐based catalysts in solid oxide cells. However, the lack of control over the ...structural evolution of host perovskites during the promotion of exsolution has restricted the architectural exploitation of exsolution‐facilitated perovskites. In this study, we strategically broke the long‐standing trade‐off phenomenon between promoted exsolution and suppressed phase transition via B‐site supplement, thus broadening the scope of exsolution‐facilitated perovskite materials. Using carbon dioxide electrolysis as an illustrative case study, we demonstrate that the catalytic activity and stability of perovskites with exsolved nanoparticles (P‐eNs) can be selectively enhanced by regulating the explicit phase of host perovskites, accentuating the critical role of the architectures of perovskite scaffold in catalytic reactions occurring on P‐eNs. The concept demonstrated could potentially pave the way for designing the advanced exsolution‐facilitated P‐eNs materials and unveiling a wide range of catalytic chemistry taking place on P‐eNs.
We have implemented a set of strategies to precisely control the phase evolution of host perovskite without compromising exsolution. Using carbon dioxide electrolysis as an example, we demonstrated how regulating phase structure can enhance the activity and stability of exsolved perovskites, emphasizing the importance of phase evolution control in catalytic chemistry occurring on perovskites with exsolution.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
•The largest publicly dataset of breast cancer pathological images is released.•Dataset diversity alleviates relatively low accuracy of benign images classification.•Richer multilevel features make ...the image-wise feature fusion more sufficient.•The short-term and long-term correlations between patches are both preserved.•Our hybrid network outperformed other methods in pathological image classification.
Even with the rapid advances in medical sciences, histopathological diagnosis is still considered the gold standard in diagnosing cancer. However, the complexity of histopathological images and the dramatic increase in workload make this task time consuming, and the results may be subject to pathologist subjectivity. Therefore, the development of automatic and precise histopathological image analysis methods is essential for the field. In this paper, we propose a new hybrid convolutional and recurrent deep neural network for breast cancer histopathological image classification. Based on the richer multilevel feature representation of the histopathological image patches, our method integrates the advantages of convolutional and recurrent neural networks, and the short-term and long-term spatial correlations between patches are preserved. The experimental results show that our method outperforms the state-of-the-art method with an obtained average accuracy of 91.3% for the 4-class classification task. We also release a dataset with 3771 breast cancer histopathological images to the scientific community that is now publicly available at http://ear.ict.ac.cn/?page_id=1616. Our dataset is not only the largest publicly released dataset for breast cancer histopathological image classification, but it covers as many different subclasses spanning different age groups as possible, thus providing enough data diversity to alleviate the problem of relatively low classification accuracy of benign images.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
An enantioselective sulfenylation/semipinacol rearrangement of 1,1‐disubstituted and trisubstituted allylic alcohols was accomplished with a chiral Lewis base and a chiral Brønsted acid as ...cocatalysts, generating various β‐arylthio ketones bearing an all‐carbon quaternary center in moderate to excellent yields and excellent enantioselectivities. These chiral arylthio ketone products are common intermediates with many applications, for example, in the design of new chiral catalysts/ligands and the total synthesis of natural products. Computational studies (DFT calculations) were carried out to explain the enantioselectivity and the role of the chiral Brønsted acid. Additionally, the synthetic utility of this method was exemplified by an enantioselective total synthesis of (−)‐herbertene and a one‐pot synthesis of a chiral sulfoxide and sulfone.
An enantioselective sulfenylation/semipinacol rearrangement of 1,1‐disubstituted and trisubstituted allylic alcohols was accomplished by chiral Lewis base/chiral Brønsted acid co‐catalysis. Various β‐arylthio ketones bearing all‐carbon quaternary centers were generated in moderate to excellent yields and excellent enantioselectivities.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Organic materials with long‐lived, color‐tunable phosphorescence are potentially useful for optical recording, anti‐counterfeiting, and bioimaging. Herein, we develop a series of novel host–guest ...organic phosphors allowing dynamic color tuning from the cyan (502 nm) to orange red (608 nm). Guest materials are employed to tune the phosphorescent color, while the host materials interact with the guest to activate the phosphorescence emission. These organic phosphors have an ultra‐long lifetime of 0.7 s and a maximum phosphorescence efficiency of 18.2 %. Although color‐tunable inks have already been developed using visible dyes, solution‐processed security inks that are temperature dependent and display time‐resolved printed images are unprecedented. This strategy can provide a crucial step towards the next‐generation of security technologies for information handling.
Multicolor swap shop: A facile doping approach for color‐tunable organic phosphorescence materials is enabled through hosts that not only restrict the molecular motion and avoid the triplet quenching from the oxygen, but also interact with the guests for the realization of phosphorescence. Color tunable, temperature dependent, and time‐resolved anti‐counterfeiting techniques are achieved by the printable and writable materials.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
Perovskites with exsolved nanoparticles (P-eNs) have immense potentials for carbon dioxide (CO
2
) reduction in solid oxide electrolysis cell. Despite the recent achievements in promoting ...the B-site cation exsolution for enhanced catalytic activities, the unsatisfactory stability of P-eNs at high voltages greatly impedes their practical applications and this issue has not been elucidated. In this study, we reveal that the formation of B-site vacancies in perovskite scaffold is the major contributor to the degradation of P-eNs; we then address this issue by fine-regulating the B-site supplement of the reduced Sr
2
Fe
1.3
Ni
0.2
Mo
0.5
O
6-
δ
using foreign Fe sources, achieving a robust perovskite scaffold and prolonged stability performance. Furthermore, the degradation mechanism from the perspective of structure stability of perovskite has also been proposed to understand the origins of performance deterioration. The B-site supplement endows P-eNs with the capability to become appealing electrocatalysts for CO
2
reduction and more broadly, for other energy storage and conversion systems.
Recently, the utilization of starch to replace synthetic polymers for the manufacture of green materials has gained extensive interest, due to its renewability, biodegradability, abundance and low ...cost. On the other hand, ionic liquids (ILs) have been widely recognized as promising "green solvents" to replace volatile organic solvents for polysaccharide processing. Over the past few years, ILs have been increasingly demonstrated to serve as excellent media for the dissolution, plasticization and derivatization of starch. This allows the synthesis of chemically modified starches with high degree of substitution (DS) and the development of various starch-based materials such as thermoplastic starch, composite films, solid polymer electrolytes, nanoparticles and drug carriers. The main objective of this review is to present an overview of the roles of ILs in starch dissolution, gelatinization, modification and plasticization, and their industrial applications. Moreover, this review is intended to provide a comprehensive understanding of the mechanisms behind the IL-processing of starch and to provide insights into the rational development of novel starch-based materials with ILs.
Recently, the use of ionic liquids as promising "green solvents" in starch chemistry has gained extensive interest, especially in the areas of chemical modification of starch and the development of starch-based materials.
Considerable efforts have been devoted to finding economic and simple preparation methods for polydimethylsiloxane (PDMS) superhydrophobic membrane in past decades. This study provides a simple ...method to electrospin PDMS membrane using poly (methyl methacrylate) (PMMA) as carrier polymer. Effects of PMMA concentration, PDMS/PMMA mass ratio and main parameters of electrospinning process (voltage and injection rate) were investigated to obtain superhydrophobic membrane with high water contact angle (WCA). A highest WCA of 163° could be obtained on the membrane surface fabricated by electrospinning solution containing PDMS: PMMA: tetrahydrofuran (THF): N,N-dimethylformamide (DMF) (mass ratio 1: 1: 8.88: 9.48) under applied voltage of 11kV and injection rate of 0.1mm/min. The superhydrophobic PDMS/PMMA membrane was further applied in membrane distillation process for desalination, and a high permeation flux of 39.61L/m2h and an excellent salt rejection of 99.96% were achieved during long-term MD process (24h).
•Superhydrophobic PDMS/PMMA membrane was electrospun successfully with a contact angle of 163°.•Correlations between electrospinning parameters and membrane properties were firstly established.•Membrane surface roughness and beads structure were well-related with membrane hydrophobicity.•The membrane was suitable for MD process (<24h) with membrane flux of 39.61L/m2h and salt rejection of 99.96%.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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