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Background: The pentose phosphate pathway (PPP) is an important mechanism by which tumour cells resist stressful environments and maintain malignant proliferation. However, the mechanism by which the PPP regulates these processes in colorectal cancer (CRC) remains elusive. Methods: Closely related PPP genes were obtained from the TCGA and GEO databases. The effect of ATP13A2 on CRC cell proliferation was evaluated by performing in vitro assays. The connection between the PPP and ATP13A2 was explored by assessing proliferation and antioxidative stress. The molecular mechanism by which ATP13A2 regulates the PPP was investigated using chromatin immunoprecipitation and dual luciferase experiments. The clinical therapeutic potential of ATP13A2 was explored using patient‐derived xenograft (PDX), patient‐derived organoid (PDO) and AOM/DSS models. Findings: We identified ATP13A2 as a novel PPP‐related gene. ATP13A2 deficiency inhibited CRC growth and PPP activity, as manifested by a decrease in the levels of PPP products and an increase in reactive oxygen species levels, whereas ATP13A2 overexpression induced the opposite effect. Mechanistically, ATP13A2 regulated the PPP mainly by affecting phosphogluconate dehydrogenase (PGD) mRNA expression. Subsequent studies showed that ATP13A2 overexpression promoted TFEB nuclear localization by inhibiting the phosphorylation of TFEB, thereby enhancing the transcription of PGD and ultimately affecting the activity of the PPP. Finally, ATP13A2 knockdown inhibited CRC growth in PDO and PDX models. ATP13A2−/− mice had a lower CRC growth capacity than ATP13A2+/+ in the AOM/DSS model.Our findings revealed that ATP13A2 overexpression‐driven dephosphorylation of TFEB promotes PPP activation by increasing PGD transcription, suggesting that ATP13A2 may serve as a potential target for CRC therapy. [ABSTRACT FROM AUTHOR]

A chemical shape‐memory hydrogel containing crystalline structure is prepared via micellar copolymerization of hydrophilic monomer acrylamide (AM) and hydrophobic monomer octadecyl acrylate (C18) in a sodium dodecyl sulfate (SDS) solution. The influence of SDS on the shape‐memory behavior of hydrogel investigated by differential scanning calorimetry (DSC) and Temperature‐dependent X‐ray indicate that the melting and crystallization peaks derived from the thermal properties of C18 units is different from peaks corresponding to the pure SDS. In addition, the microstructure evolution information of hydrogels dose not change upon heating process, regardless of the presence or absence of SDS. Therefore, only the hydrophobic associations formed by C18 blocks play a decisive role in the shape memory function of hydrogel system. The difference between the transition process (from temporary shape to permanent shape) of hydrogel with and without SDS at different temperature is because that the hydrophobic region of side chain crystallization of SDS‐free hydrogel may escape the restriction of SDS and become more sensitive to temperature, they can preferentially return to their initial shape under the same time and temperature than SDS‐containing gels. Whether SDS exists only affect the speed of shape memory behavior, but not the microstructure evolution of hydrogel system. [ABSTRACT FROM AUTHOR]

Mica nanolayers (MNL) are a new dielectric material that can improve the electron transport properties of Si based microelectronic devices. However, the mechanical reliability of such devices is not well understood because measurement of the adhesion between an MNL and a Si substrate is insufficiently accurate. The recent work reports a bridging method that is developed based on the linear beam theory and can characterize the adhesion of MNL on a mica substrate in a reasonably accuracy. In this work, the accuracy of the bridging method is improved by using a nonlinear mechanical model. 15 MNL specimens are measured on a Si substrate in air and the new model gives an average adhesion energy of 119.69 ± 20.47 mJ m–2. The effect of environment on the adhesion is also investigated. The increase in temperature from 25 to 300 °C enhances adhesion, attributed to the increased bonding effect of interfacial contaminants. When humidity is below a threshold value, 80% in this case, the adhesion energy remains unchanged, but above the threshold, the nanobridges collapse during testing. Molecular dynamics simulation reveal that the collapse is because the increase of interfacial water molecules reduces the frictional force between the MNL and Si substrate. [ABSTRACT FROM AUTHOR]

Abstract: PIWI‐interacting RNAs (piRNAs) silence transposons in germ cells to maintain genome stability and animal fertility. Rhino, a rapidly evolving heterochromatin protein 1 (HP1) family protein, binds Deadlock in a species‐specific manner and so defines the piRNA‐producing loci in the Drosophila genome. Here, we determine the crystal structures of Rhino‐Deadlock complex in Drosophila melanogaster and simulans. In both species, one Rhino binds the N‐terminal helix–hairpin–helix motif of one Deadlock protein through a novel interface formed by the beta‐sheet in the Rhino chromoshadow domain. Disrupting the interface leads to infertility and transposon hyperactivation in flies. Our structural and functional experiments indicate that electrostatic repulsion at the interaction interface causes cross‐species incompatibility between the sibling species. By determining the molecular architecture of this piRNA‐producing machinery, we discover a novel HP1‐partner interacting mode that is crucial to piRNA biogenesis and transposon silencing. We thus explain the cross‐species incompatibility of two sibling species at the molecular level. [ABSTRACT FROM AUTHOR]

In the past two decades, the reaction mechanism of C−C bond formation from either methanol or dimethyl ether (DME) in the methanol-to-hydrocarbons (MTH) process has been a highly controversial issue. Described here is the first observation of a surface methyleneoxy analogue, originating from the surface-activated DME, by in situ solid-state NMR spectroscopy, a species crucial to the first C−C bond formation in the MTH process. New insights into the first C−C bond formation were provided, thus suggesting DME/methanol activation and direct C−C bond formation by an interesting synergetic mechanism, involving C−H bond breakage and C−C bond coupling during the initial methanol reaction within the chemical environment of the zeolite catalyst. [ABSTRACT FROM AUTHOR]

Nanocomposites consisting of a poly(vinylidene fluoride) (PVDF) matrix and 0-8 wt% fluoropropyl polyhedral oligomeric silsesquioxane (FP-POSS) were obtained through the solvent evaporation method. Morphology, crystallization, as well as thermal and mechanical properties were investigated. FP-POSS, acting as a nucleating agent, exhibited robust miscibility with PVDF, enhancing the crystallinity of PVDF. A high relative fraction of the β phase was observed in the composites. The thermal degradation of PVDF was not significantly affected by FP-POSS under a nitrogen atmosphere. Low addition of FP-POSS, acting as nanofiller, led to remarkable improvement in mechanical properties, including hardness. The maximum was achieved at 3 wt%. High amounts led to inferior mechanical properties. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Mica nanolayers have great potential for applications in the future flexible electronics due to their excellent flexibility and dielectric properties. Characterization of the adhesion behaviors of mica nanolayers is thus essential, as they would substantially affect the reliability of the electronic devices. In this work, a new delamination method is developed based on the optical microscopic nanomanipulation for measuring the adhesion energy of mica nanolayers. In particular, the tests are performed under different environmental conditions with relative humidity varying from 10% to 90% and temperature ranging from 25 to 300 °C. The average surface energy of mica nanolayers is 221.5 ± 25.4 mJ m−2 measured at the room temperature of 25 °C and decreases with the increase in relative humidity or temperature. The finding of the environmentally dependent adhesion is of importance for the design of flexible electronics products based on mica nanolayers. In this paper, a new method is introduced to measure adhesion of nanomaterials based on the bridge fabricated by nanomanipulation. The adhesion of mica nanolayer is investigated to demonstrate the advantage of this method, which could not be achieved by previous methods. Moreover, this method also fills the blank of studying the influence of environmental factors on the adhesion of nanomaterials. [ABSTRACT FROM AUTHOR]

A novel nanobridge test based on optical microscopy based nanomanipulation is developed to explore the adhesion of mica nanolayers under controlled environmental conditions. The nanomanipulation process displayed here is expected to be universal for the adhesion of any nanolayer‐substrate systems. More details can be found in article number 1801552 by Bowen Yu, Lizhen Hou, Shiliang Wang, and Han Huang. [ABSTRACT FROM AUTHOR]

The first carbon–carbon bond formation in the methanol to hydrocarbons (MTH) reaction over zeolite catalysts has been a highly controversial issue and has puzzled scientists for 30 years. In their Communication on page 9039 ff. Z. Liu, Y. Wei et al. propose a direct mechanism for the formation of the first C−C bond in the MTH reaction, based on the detection of the crucial intermediate, a surface methyleneoxy analogue species originating from activated DME or methanol, by in situ solid‐state NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Der erste C ‐ C ‐ Verknüpfungsschritt bei der Umwandlung von Methanol in Kohlenwasserstoffe über Zeolithkatalysatoren wird seit 30 Jahren kontrovers diskutiert. In ihrer Zuschrift auf S. 9167 ff. schlagen Z. Liu, Y. Wei et al. einen Mechanismus für diesen Schritt vor. Ihr Postulat gründet auf dem Nachweis einer Methylenoxy ‐ analogen Oberflächenspezies, gebildet aus aktiviertem Dimethylether oder Methanol, durch In ‐ situ ‐ Festkörper ‐ NMR ‐ Spektroskopie. [ABSTRACT FROM AUTHOR]