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Osteoporosis is a highly prevalent public health burden associated with an increased risk of bone fracture, particularly in aging women. Estrogen, an important medicinal component for the preventative and therapeutic treatment of postmenopausal osteoporosis, induces osteogenesis by activating the estrogen receptor signaling pathway and upregulating the expression of osteogenic genes, such as bone morphogenetic proteins (BMPs). The epigenetic regulation of estrogen-mediated osteogenesis, however, is still unclear. In this report, we found that estrogen significantly induced the expression of lysine-specific demethylase 6B (KDM6B) and that KDM6B depletion by shRNAs led to a significant reduction in the osteogenic potential of DMSCs. Mechanistically, upon estrogen stimulation, estrogen receptor-α (ERα) was recruited to the KDM6B promoter, directly enhancing KDM6B expression. Subsequently, KDM6B was recruited to the BMP2 and HOXC6 promoters, resulting in the removal of H3K27me3 marks and activating the transcription of BMP2 and HOXC6, the master genes of osteogenic differentiation. Furthermore, we found that estrogen enhanced DMSC osteogenesis during calvarial bone regeneration and that estrogen's pro-osteogenic effect was dependent on KDM6B in vivo. Taken together, our results demonstrate the vital role of the ERα/KDM6B regulatory axis in the epigenetic regulation of the estrogen-dependent osteogenic response.

The inelastic scattering length (Ls) is a length scale of fundamental importance in condensed matters due to the relationship between inelastic scattering and quantum dephasing. In quantum anomalous Hall (QAH) materials, the mesoscopic length scale Ls plays an instrumental role in determining transport properties. Here we examine Ls in three regimes of the QAH system with distinct transport behaviors: the QAH, quantum critical, and insulating regimes. Although the resistance changes by five orders of magnitude when tuning between these distinct electronic phases, scaling analyses indicate a universal Ls among all regimes. Finally, mesoscopic scaled devices with sizes on the order of Ls were fabricated, enabling the direct detection of the value of Ls in QAH samples. Our results unveil the fundamental length scale that governs the transport behavior of QAH materials.

Immunosurveillance is a critical mechanism guarding against tumor development and progression. Checkpoint inhibitors have shown significant success in cancer treatment, but expression of key factors such as PD-L1 in putative cancer stem cell (CSC) populations in squamous cell carcinoma has been inconclusive, suggesting that CSCs may have developed other mechanisms to escape immune surveillance. Here we show that CSCs upregulate the immune checkpoint molecule CD276 (B7-H3) to evade host immune responses. CD276 is highly expressed by CSCs in mouse and human head and neck squamous cell carcinoma (HNSCC) and can be used to prospectively isolate tumorigenic CSCs. Anti-CD276 antibodies eliminate CSCs in a CD8+ T cell-dependent manner, inhibiting tumor growth and lymph node metastases in a mouse HNSCC model. Single-cell RNA sequencing (RNA-seq) showed that CD276 blockade remodels SCC heterogeneity and reduces epithelial-mesenchymal transition. These results show that CSCs utilize CD276 for immune escape and suggest that targeting CD276 may reduce CSCs in HNSCC.

In this work, CoFe-based oxide nanosheets were prepared by a facile method and its catalysis effects on the thermal decomposition of ammonium perchlorate (AP) were studied. CoFe-based oxide nanosheets were obtained from hydrothermal process and high-temperature treatment of CoFe-layered double hydroxide. The samples were characterized by scanning electron microscopy and high-resolution transmission electron microscopy. The thermal catalytic decomposition of AP with CoFe-based oxide nanosheets as catalysts was investigated by differential scanning calorimetry and coupling Fourier transform infrared spectrometer. The results showed that the CoFe-based oxide samples with the width size of 200-300 nm and the thickness size of ~10 nm show the inherent catalytic ability. With 10 wt% of CoFe-based oxide nanosheets added, the decomposition temperature of AP was reduced by 127.5 [degrees]C from 431.0 [degrees]C to 303.5 [degrees]C. The apparent activation energy was decreased by 61.1 kJ/mol from 177.3 kJ/mol of raw AP to 116.2 kJ/mol of AP with 10 wt% of CoFe-based oxide nanosheets added. The thermal catalysis decomposition mechanism of AP with CoFe-based oxide nanosheet material promoting was proposed. This work offered a novel idea toward preparation and application of functional material layered double hydroxide in the field of energetic materials. Key words: CoFe-based oxide nanosheets, facile preparation, layered double hydroxide, ammonium perchlorate, thermal decomposition Dans le cadre des presents travaux, nous avons prepare par une methode simple des nanofeuillets d'oxydes a base de CoFe et nous avons etudie leurs effets catalytiques sur la decomposition thermique du perchlorate d'ammonium (PA). Les nanofeuillets d'oxydes a base de CoFe ont ete obtenus a l'aide d'un procede hydrothermal et d'un traitement a haute temperature d'un hydroxyde double lamellaire a base de CoFe. Les echantillons ont ete caracterises par microscopie electronique a balayage (MEB) et par microscopie electronique en transmission a haute resolution (METHR). Nous avons etudie la decomposition thermique catalytique du PA en presence des nanofeuillets d'oxydes a base de CoFe employes comme catalyseurs. Pour ce faire, nous avons utilise la calorimetrie differentielle a balayage (DSC) et l'analyse thermogravimetrique couplee a la spectroscopie infrarouge a transformee de Fourier (ATG-FTIR). Les resultats ont montre que les echantillons d'oxydes a base de CoFe d'une largeur de 200 a 300 nm et d'une epaisseur d'environ 10 nm presentent une capacite catalytique inherente. L'ajout de 10 % p/p de nanofeuillets d'oxydes a base de CoFe a eu pour effet de reduire la temperature de decomposition du PA de 127,5 [degrees]C, la faisant passer de 431,0 [degrees]C a 303,5 [degrees]C. L'energie d'activation apparente a diminue de 61,1 kJ/mol, passant de 177,3 kJ/mol pour le PA seul a 116,2 kJ/mol pour le PA additionne de nanofeuillets d'oxydes a base de CoFe. Nous proposons un mecanisme pour la decomposition thermique du PA catalysee par les nanofeuillets d'oxydes a base de CoFe. Ces travaux pourront inspirer d'autres etudes sur la preparation et les applications des hydroxydes doubles lamellaires comme materiaux fonctionnels dans le domaine des materiaux energetiques. [Traduit par la Redaction] Mots-cles : nanofeuillets d'oxydes a base de CoFe, preparation facile, hydroxyde double lamellaire, perchlorate d'ammonium, decomposition thermique, 1. Introduction Layered double hydroxide, as a new functional material with two-dimensional structure, had received much attention in the fields of catalysis, adsorption, and energy. (1-5) The unique two-dimensional structure [...]

This work reports the ferromagnetism of topological insulator, (Bi,Sb)2Te3 (BST), with a Curie temperature of approximately 120 K induced by magnetic proximity effect (MPE) of an antiferromagnetic CrSe. The MPE was shown to be highly dependent on the stacking order of the heterostructure, as well as the interface symmetry: Growing CrSe on top of BST results in induced ferromagnetism, while growing BST on CrSe yielded no evidence of an MPE. Cr-termination in the former case leads to double-exchange interactions between Cr3+ surface states and Cr2+ bulk states. This Cr3+-Cr2+ exchange stabilizes the ferromagnetic order localized at the interface and magnetically polarizes the BST Sb band. In contrast, Se-termination at the CrSe/BST interface yields no detectable MPE. These results directly confirm the MPE in BST films and provide critical insights into the sensitivity of the surface state.

Quantum anomalous Hall effect has been observed in magnetically doped topological insulators. However, full quantization, up until now, is limited within the sub-1 K temperature regime, although the material's magnetic ordering temperature can go beyond 100 K. Here, we study the temperature limiting factors of the effect in Cr-doped (BiSb)2Te3 systems using both transport and magneto-optical methods. By deliberate control of the thin-film thickness and doping profile, we revealed that the low occurring temperature of quantum anomalous Hall effect in current material system is a combined result of weak ferromagnetism and trivial band involvement. Our findings may provide important insights into the search for high-temperature quantum anomalous Hall insulator and other topologically related phenomena.

Objective To explore the application of support vector machine (SVM) in predicting the mortality risk after intensive care unit (ICU) admission. Methods A total of 18 094 ICU inpatients from MIMIC Ⅲ dataset were enrolled in the study. The total data set (n=18 094) was randomly divided into training data set (n=12 666, 70%) and test data set (n=5 428, 30%). Based on the Python, the machine learning algorithm, SVM, was used to establish a prediction model of the mortality risk after ICU admission with the results of LASSO feature selection. The efficacy of model was evaluated using the test data set. Results The areas under the receiver operating characteristic (AUCROC) curves of the SVM-based model for predicting the mortality risk in 24 h and 48 h after ICU admission were 0.805 1 (0.793 6~0.816 6) and 0.811 7 (0.799 9~0.824), with sensitivities of 0.751 3 and 0.737 2, and specificities of 0.713 0 and 0.742 9, respectively. Conclusion The SVM-based model for predicting the mortality risk after ICU admission has a satisfactory result and high accuracy.

The catalysis effects of MgC[o.sub.2][O.sub.4] nanosheets on the thermal decomposition of ammonium perchlorate (AP) were investigated. The MgC[o.sub.2][O.sub.4] nanosheets were synthesized with a facile free-template hydrothermal method. The chemical structure and micromorphology of MgC[o.sub.2][O.sub.4] nanosheets were characterized. Moreover, the catalysis thermal decomposition properties of AP using composite metal oxides MgC[o.sub.2][O.sub.4] nanosheets with different amounts (1 wt%, 3 wt%, and 5 wt%) as catalysts were investigated. The results showed that the reducing decomposition temperature of AP was 155.9 [degrees]C from 431 [degrees]C to 275.1 [degrees]C with 5 wt% MgC[o.sub.2][O.sub.4] added. The heat release of AP was increased by 907 J/g at least. In addition, the catalysis thermal decomposition mechanism of AP with the existence of MgC[o.sub.2][O.sub.4] nanosheets was explained. With the increasing temperature, the accumulated electrons ([e.sup.-]) and holes ([h.sup.+]) excited were activated at the surface of MgC[o.sub.2][O.sub.4] nanosheets, which accelerated H transfer from H atom of N[H.sup.+.sub.4] to O atom of Cl[O.sup.-.sub.4] and boosted AP decomposition. Key words: MgC[o.sub.2][O.sub.4] nanosheets, ammonium perchlorate, thermal catalysis, decomposition performance, catalysis mechanism. Nous avons étudié les effets catalytiques de nanofeuillets de MgC[o.sub.2][O.sub.4] sur la décomposition thermique du perchlorate d'ammonium (PA). Ces nanofeuillets de MgC[o.sub.2][O.sub.4] ont été synthétisés au moyen d'une méthode hydrothermale simple sans agent structurant. Leur structure chimique et leur micromorphologie ont été caractérisées. En outre, nous avons étudié les propriétés de la décomposition thermique catalytique du PA en utilisant les nanofeuillets d'oxydes métalliques composites comme cataly-seurs à différentes teneurs en MgC[o.sub.2][O.sub.4] (1 % p/p, 3 % p/p et 5 % p/p). Les résultats ont montré que la température de décomposition du PA diminue de 155,9 [degrees]C, passant de 431 [degrees]C à 275,1 [degrees]C, avec l'ajout de MgC[o.sub.2][O.sub.4] à 5 % p/p. La libération de chaleur du PA augmente d'au moins 907 J/g dans ces conditions. De plus, nous avons élucidé le mécanisme catalytique de décomposition thermique du PA en présence de nanofeuillets de MgC[o.sub.2][O.sub.4]. Lorsque la température augmente, les électrons accumulés ([e.sup.-]) et les trous ([h.sup.+]) excités sont activés à la surface des nanofeuillets de MgC[o.sub.2][O.sub.4], ce qui accélère le transfert d'atomes d'hydrogène de l'ion N[H.sup.+.sub.4] à l'atome d'oxygène de l'ion Cl[O.sup.-.sub.4] et favorise la décomposition du PA. [Traduit par la Rédaction] Mots-clés : nanofeuillets de MgC[o.sub.2][O.sub.4], perchlorate d'ammonium, catalyse thermique, performance de décomposition, mécanisme catalytique., 1. Introduction Ammonium perchlorate (AP), due to its strong oxidation capability, has attracted much attention in composite solid rocket propellant systems. (1) As a common oxidizer usually occupying 60%-90% content [...]