ALBERT

Description: 〈p〉The interaction between gastric epithelium and immune response plays key roles in 〈i〉H. pylori〈/i〉–associated pathology. We demonstrated a procolonization and proinflammation role of MMP-10 in 〈i〉H. pylori〈/i〉 infection. MMP-10 is elevated in gastric mucosa and is produced by gastric epithelial cells synergistically induced by 〈i〉H. pylori〈/i〉 and IL-22 via the ERK pathway. Human gastric MMP-10 was correlated with 〈i〉H. pylori〈/i〉 colonization and the severity of gastritis, and mouse MMP-10 from non–BM-derived cells promoted bacteria colonization and inflammation. 〈i〉H. pylori〈/i〉 colonization and inflammation were attenuated in IL-22〈sup〉–/–〈/sup〉, MMP-10〈sup〉–/–〈/sup〉, and IL-22〈sup〉–/–〈/sup〉MMP-10〈sup〉–/–〈/sup〉 mice. MMP-10–associated inflammation is characterized by the influx of CD8〈sup〉+〈/sup〉 T cells, whose migration is induced via MMP-10–CXCL16 axis by gastric epithelial cells. Under the influence of MMP-10, Reg3a, E-cadherin, and zonula occludens–1 proteins decrease, resulting in impaired host defense and increased 〈i〉H. pylori〈/i〉 colonization. Our results suggest that MMP-10 facilitates 〈i〉H. pylori〈/i〉 persistence and promotes gastritis.〈/p〉

Description: 〈p〉The massless Dirac electron transport in graphene has led to a variety of unique light-matter interaction phenomena, which promise many novel optoelectronic applications. Most of the effects are only accessible by breaking the spatial symmetry, through introducing edges, p-n junctions, or heterogeneous interfaces. The recent development of direct synthesis of lateral heterostructures offers new opportunities to achieve the desired asymmetry. As a proof of concept, we study the photothermoelectric effect in an asymmetric lateral heterojunction between the Dirac semimetallic monolayer graphene and the parabolic semiconducting monolayer MoS〈sub〉2〈/sub〉. Very different hot-carrier cooling mechanisms on the graphene and the MoS〈sub〉2〈/sub〉 sides allow us to resolve the asymmetric thermalization pathways of photoinduced hot carriers spatially with electrostatic gate tunability. We also demonstrate the potential of graphene-2D semiconductor lateral heterojunctions as broadband infrared photodetectors. The proposed structure shows an extreme in-plane asymmetry and provides a new platform to study light-matter interactions in low-dimensional systems.〈/p〉

Description: 〈p〉An important reasons for drug relapse is the retrieval of drug withdrawal memory induced by conditioned context. Previous studies have suggested that the basolateral amygdala (BLA) plays an important role in conditioned context–induced retrieval of morphine withdrawal memory. However, the downstream neuronal circuits of the activation of the BLA in conditioned context–induced retrieval of morphine withdrawal memory remain unknown. Using retrograde labeling, immunohistochemical, and optogenetic approaches, we found that, although BLA neurons projecting to the prelimbic cortex (PrL) played an important role in conditioned context–induced retrieval of morphine withdrawal memory, they do not exhibit increased expression of the neuronal plasticity marker Arc. However, when PrL neurons activated by the BLA send feedback signals to the BLA, a neuronal-related process is induced in other BLA neurons that do not project to the PrL, a finding that is relevant to conditioned context–induced retrieval of morphine withdrawal memory.〈/p〉

Description: 〈p〉The control of product distribution in a multistep catalytic selective hydrogenation reaction is challenging. For instance, the deep hydrogenation of dimethyl oxalate (DMO) is inclined to proceed over Cu/SiO〈sub〉2〈/sub〉 catalysts because of inevitable coexistence of Cu〈sup〉+〈/sup〉 and Cu〈sup〉0〈/sup〉, leading to hard acquisition of the preliminary hydrogenation product, methyl glycolate (MG). Here, the oriented DMO hydrogenation into MG is achieved over the sputtering (SP) Cu/SiO〈sub〉2〈/sub〉 catalysts with a selectivity of more than 87% via freezing Cu in a zero-valence state. Our density functional theory calculation results revealed that Cu〈sup〉0〈/sup〉 is the active site of the preliminary hydrogenation step, selectively converting DMO to MG via •H addition, while Cu〈sup〉+〈/sup〉 is a key factor for deep hydrogenation. The prominent Coster-Kronig transition enhancement is observed over SP-Cu/SiO〈sub〉2〈/sub〉 from Auger spectra, indicating that the electron density of inner shells in Cu atoms is enhanced by high-energy argon plasma bombardment during the SP process. Thus, the "penetration effect" of outermost electrons could also be enhanced, making these Cu nanoparticles exhibit high oxidation resistance ability and present noble metal–like behaviors as Au or Ag. Therefore, the regulation of Cu chemical properties by changing the electron structure is a feasible strategy to control the hydrogenation products, inspiring the rational design of selective hydrogenation catalysts.〈/p〉

Description: Tumor lymphangiogenesis is accompanied by a higher incidence of sentinel lymph node metastasis and shorter overall survival in several types of cancer. We asked whether tumor lymphangiogenesis might also occur in distant organs with established metastases and whether it might promote further metastatic spread of those metastases to other organs. Using mouse metastasis models, we found that lymphangiogenesis occurred in distant lung metastases and that some metastatic tumor cells were located in lymphatic vessels and draining lymph nodes. In metastasis-bearing lungs of melanoma patients, a higher lymphatic density within and around metastases and lymphatic invasion correlated with poor outcome. Using a transgenic mouse model with inducible expression of vascular endothelial growth factor C (VEGF-C) in the lung, we found greater growth of lung metastases, with more abundant dissemination to other organs. Our findings reveal unexpected contributions of lymphatics in distant organs to the promotion of growth of metastases and their further spread to other organs, with potential clinical implications for adjuvant therapies in patients with metastatic cancer.

Description: We report the discovery of the hydrotropic properties of a recyclable aromatic acid, p -toluenesulfonic acid ( p -TsOH), for potentially low-cost and efficient fractionation of wood through rapid and near-complete dissolution of lignin. Approximately 90% of poplar wood (NE222) lignin can be dissolved at 80°C in 20 min. Equivalent delignification using known hydrotropes, such as aromatic salts, can be achieved only at 150°C or higher for more than 10 hours or at 150°C for 2 hours with alkaline pulping. p -TsOH fractionated wood into two fractions: (i) a primarily cellulose-rich water-insoluble solid fraction that can be used for the production of high-value building blocks, such as dissolving pulp fibers, lignocellulosic nanomaterials, and/or sugars through subsequent enzymatic hydrolysis; and (ii) a spent acid liquor stream containing mainly dissolved lignin that can be easily precipitated as lignin nanoparticles by diluting the spent acid liquor to below the minimal hydrotrope concentration. Our nuclear magnetic resonance analyses of the dissolved lignin revealed that p -TsOH can depolymerize lignin via ether bond cleavage and can separate carbohydrate-free lignin from the wood. p -TsOH has a relatively low water solubility, which can facilitate efficient recovery using commercially proven crystallization technology by cooling the concentrated spent acid solution to ambient temperatures to achieve environmental sustainability through recycling of p -TsOH.

Description: Graphene and other two-dimensional materials have unique physical and chemical properties of broad relevance. It has been suggested that the transformation of these atomically planar materials to three-dimensional (3D) geometries by bending, wrinkling, or folding could significantly alter their properties and lead to novel structures and devices with compact form factors, but strategies to enable this shape change remain limited. We report a benign thermally responsive method to fold and unfold monolayer graphene into predesigned, ordered 3D structures. The methodology involves the surface functionalization of monolayer graphene using ultrathin noncovalently bonded mussel-inspired polydopamine and thermoresponsive poly( N -isopropylacrylamide) brushes. The functionalized graphene is micropatterned and self-folds into ordered 3D structures with reversible deformation under a full control by temperature. The structures are characterized using spectroscopy and microscopy, and self-folding is rationalized using a multiscale molecular dynamics model. Our work demonstrates the potential to design and fabricate ordered 3D graphene structures with predictable shape and dynamics. We highlight applicability by encapsulating live cells and creating nonlinear resistor and creased transistor devices.

Description: The advent of topological insulators (TIs), a novel class of materials that harbor a metallic spin-chiral surface state coexisting with band-insulating bulk, opens up new possibilities for spintronics. One promising route is current-induced switching of an adjacent magnetic layer via spin-orbit torque (SOT), arising from the large spin-orbit coupling intrinsically possessed by TIs. The Kondo insulator SmB 6 has been recently proposed to be a strongly correlated TI, supported by the observation of a metallic surface state in bulk SmB 6 , as evidenced by the thickness independence of the low-temperature resistance plateau. We report the synthesis of epitaxial (001) SmB 6 /Si thin films and a systematic thickness-dependent electrical transport study. Although the low-temperature resistance plateau is observed for all films from 50 to 500 nm in thickness, the resistance is distinctively thickness-dependent and does not support the notion of surface conduction and interior insulation. On the other hand, we demonstrate that SmB 6 can generate a large SOT to switch an adjacent ferromagnetic layer, even at room temperature. The effective SOT generated from SmB 6 is comparable to that from β-W, one of the strongest SOT materials.

Description: A deposition process has been developed to fabricate a complete-monolayer Pt coating on a large-surface-area three-dimensional (3D) Ni foam substrate using a buffer layer (Ag or Au) strategy. The quartz crystal microbalance, current density analysis, cyclic voltammetry integration, and X-ray photoelectron spectroscopy results show that the monolayer deposition process accomplishes full coverage on the substrate and the deposition can be controlled to a single atomic layer thickness. To our knowledge, this is the first report on a complete-monolayer Pt coating on a 3D bulk substrate with complex fine structures; all prior literature reported on submonolayer or incomplete-monolayer coating. A thin underlayer of Ag or Au is found to be necessary to cover a very reactive Ni substrate to ensure complete-monolayer Pt coverage; otherwise, only an incomplete monolayer is formed. Moreover, the Pt monolayer is found to work as well as a thick Pt film for catalytic reactions. This development may pave a way to fabricating a high-activity Pt catalyst with minimal Pt usage.