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91.
Long‐Range Domain Structure and Symmetry Engineering by Interfacial Oxygen Octahedral Coupling at Heterostructure Interface 下载免费PDF全文
Zhaoliang Liao Robert J. Green Nicolas Gauquelin Sebastian Macke Lin Li Julie Gonnissen Ronny Sutarto Evert P. Houwman Zhicheng Zhong Sandra Van Aert Johan Verbeeck George A. Sawatzky Mark Huijben Gertjan Koster Guus Rijnders 《Advanced functional materials》2016,26(36):6627-6634
In epitaxial thin film systems, the crystal structure and its symmetry deviate from the bulk counterpart due to various mechanisms such as epitaxial strain and interfacial structural coupling, which is accompanyed by a change in their properties. In perovskite materials, the crystal symmetry can be described by rotations of sixfold coordinated transition metal oxygen octahedra, which are found to be altered at interfaces. Here, it is unraveled how the local oxygen octahedral coupling at perovskite heterostructural interfaces strongly influences the domain structure and symmetry of the epitaxial films resulting in design rules to induce various structures in thin films using carefully selected combinations of substrate/buffer/film. Very interestingly it is discovered that these combinations lead to structure changes throughout the full thickness of the film. The results provide a deep insight into understanding the origin of induced structures in a perovskite heterostructure and an intelligent route to achieve unique functional properties. 相似文献
92.
Isabelle Six Nicolas Guillaume Valentine Jacob Romuald Mentaverri Said Kamel Agns Boullier Michel Slama 《International journal of molecular sciences》2022,23(11)
The endothelium has a fundamental role in the cardiovascular complications of coronavirus disease 2019 (COVID-19). Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) particularly affects endothelial cells. The virus binds to the angiotensin-converting enzyme 2 (ACE-2) receptor (present on type 2 alveolar cells, bronchial epithelial cells, and endothelial cells), and induces a cytokine storm. The cytokines tumor necrosis factor alpha, interleukin-1 beta, and interleukin-6 have particular effects on endothelial cells—leading to endothelial dysfunction, endothelial cell death, changes in tight junctions, and vascular hyperpermeability. Under normal conditions, apoptotic endothelial cells are removed into the bloodstream. During COVID-19, however, endothelial cells are detached more rapidly, and do not regenerate as effectively as usual. The loss of the endothelium on the luminal surface abolishes all of the vascular responses mediated by the endothelium and nitric oxide production in particular, which results in greater contractility. Moreover, circulating endothelial cells infected with SARS-CoV-2 act as vectors for viral dissemination by forming clusters that migrate into the circulation and reach distant organs. The cell clusters and the endothelial dysfunction might contribute to the various thromboembolic pathologies observed in COVID-19 by inducing the formation of intravascular microthrombi, as well as by triggering disseminated intravascular coagulation. Here, we review the contributions of endotheliopathy and endothelial-cell-derived extracellular vesicles to the pathogenesis of COVID-19, and discuss therapeutic strategies that target the endothelium in patients with COVID-19. 相似文献
93.
Aurlie Charazac Charlotte Hinault Bastien Dolfi Solne Hautier Clia Decond Le Butor Frdric Bost Nicolas Chevalier 《International journal of molecular sciences》2022,23(14)
Endocrine Disrupting Compounds (EDCs) are found in everyday products. Widely distributed throughout the environment, persistent organic pollutants (POPs) are a specific class of EDCs that can accumulate in adipose tissue. Many of them induce adverse effects on human health—such as obesity, fertility disorders and cancers—by perturbing hormone effects. We previously identified many compounds with EDC activity in the circulation of obese patients who underwent bariatric surgery. Herein, we analyzed the effects of four of them (aldrin, BDE28, PFOA and PCB153) on two cancer cell lines of hormone-sensitive organs (prostate and breast). Each cell line was exposed to serial dilutions of EDCs from 10−6 M to 10−12 M; cytotoxicity and proliferation were monitored using the IncuCyte® technology. We showed that none of these EDCs induce cytotoxicity and that PFOA and PCB153, only at very low doses (10−12 M), increase the proliferation of DU145 (prostate cancer) and MCF7 (breast cancer) cells, while the same effects are observed with high concentrations (10−6 M) for aldrin or BDE28. Regarding the mechanistic aspects, PFOA uses two different signaling pathways between the two lines (the Akt/mTORC1 and PlexinD1 in MCF7 and DU145, respectively). Thus, our study demonstrates that even at picomolar (10−12 M) concentrations PFOA and PCB153 increase the proliferation of prostate and breast cancer cell lines and can be considered possible carcinogens. 相似文献
94.
Constance Mayslich Philippe Alain Grange Mathieu Castela Anne Genevive Marcelin Vincent Calvez Nicolas Dupin 《International journal of molecular sciences》2022,23(9)
Cutibacterium acnes (C. acnes) has been implicated in inflammatory acne where highly mutated Christie–Atkins–Munch–Petersen factor (CAMP)1 displays strong toll like receptor (TLR)-2 binding activity. Using specific antibodies, we showed that CAMP1 production was independent of C. acnes phylotype and involved in the induction of inflammation. We confirmed that TLR-2 bound both mutated and non-mutated recombinant CAMP1, and peptide array analysis showed that seven peptides (A14, A15, B1, B2, B3, C1 and C3) were involved in TLR-2 binding, located on the same side of the three-dimensional structure of CAMP1. Both mutated and non-mutated recombinant CAMP1 proteins induced the production of C-X-C motif chemokine ligand interleukin (CXCL)8/(IL)-8 in vitro in keratinocytes and that of granulocyte macrophage-colony stimulating factor (GM-CSF), tumor necrosis factor (TNF)-α, IL-1β and IL-10 in ex vivo human skin explants. Only A14, B1 and B2 inhibited the production of CXCL8/IL-8 by keratinocytes and that of (GM-CSF), TNF-α, IL-1β and IL-10 in human skin explants stimulated with rCAMP1 and C. acnes. Following pretreatment with B2, RNA sequencing on skin explants identified the 10 genes displaying the strongest differential expression as IL6, TNF, CXCL1, CXCL2, CXCL3, CXCL8, IL-1β, chemokine ligand (CCL)2, CCL4 and colony stimulating factor (CSF)2. We, thus, identified a new CAMP1-derived peptide as a TLR-2 modulator likely to be a good candidate for clinical evaluation. 相似文献
95.
96.
Based on the time-domain quality factor (Q-factor) measurement principle, an architecture which not only achieves an accurate Q-factor at the specific frequency but also covers a range of frequencies without any loss in Q-factor measurement accuracy is proposed. Based on a reconfigurable structure, an improved peak detector compensation method is presented. To guide the design of such an architecture, a theoretical analysis for reaching the required accuracy and expanding the input frequency range has been first developed in this paper. Besides, the system power dissipation can be reduced by 7.5% thanks to the improved digital control logic. In this paper, circuit is realized in a 0.35μm CMOS process for the first time. With the 5V supply voltage and 1MHz input frequency, the post-layout simulation result have demonstrated that an accuracy of the Q-factor measurement is within 0.2%. Furthermore, the input frequency range that can be measured by this circuit is extended from 100kHz to 1.5MHz with the same accuracy. 相似文献
97.
Based on new comparison principles that take into account both the volume of scientific production and its impact, this paper proposes a method for defining reference classes of universities. Several tools are developed in order to enable university managers to define the value system according to which their university shall be compared to others. We apply this methodology to French universities and illustrate it using the reference classes of the best ranked universities according to several value systems. 相似文献
98.
99.
Sofiane Aloui Nicolas Delaunay Eric Kerherve Nathalie Deltimple Robert Plana Didier Belot 《Analog Integrated Circuits and Signal Processing》2012,70(2):203-211
A millimeter-wave Power Amplifier (PA) based on a 65nm CMOS technology from STMicroelectronics has been designed. The targeted
feature is the unlicensed band around 60 GHz suitable for wireless personal area network application (WPAN). To optimize the
linearity, the PA is designed under class A biasing to have an output compression point (OCP1) close to its saturated Power (P
sat). S-parameters and large signal measurement results are demonstrated and compared with electromagnetic simulations. The PA
offers a P
sat of 8.3 dBm, an OCP1 of 6 dBm and a gain of 6.7 dB. The die area is 0.29 mm2 with pads. Considering those results, one-tone simulations are not sufficient to characterize the linearity performances
of the PA in its real conditions of use. Consequently, two-tone simulations are firstly performed. After, linearity figures
of merit (FoM) are discussed applying an orthogonal frequency-division multiplexing (OFDM) modulated signal. The PA offers
an adjacent channel power ratio (ACPR) of 15 dB and an error vector magnitude (EVM) of 20% at PA compression operating mode. 相似文献
100.