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A triphenyl-pentacarboxylic acid, 3,5-di(2′,4′-dicarboxylphenyl)benzoic acid (H5ddba), was applied as an adaptable linker for the hydrothermal assembly of eight new metal(II) coordination polymers (CPs) and complexes, formulated as [Cu2(μ-H3ddba)2(phen)2] (1), {[Cd2(μ4-Hddba)(phen)2(H2O)2]·2H2O}n (2), [M4(μ3-Hddba)2(2,2′-bipy)6(μ-H2O)]·6H2O (M = Ni (3), Mn (4)), {[Co2(μ5-Hddba)(μ-4,4′-bipy)1.5(H2O)]·H2O}n (5), {[Zn2(μ5-Hddba)(4,4′-bipy)1.5]·4,4′-bipy·2H2O}n (6), [Mn2(μ6-Hddba)(H2biim)(H2O)]n (7), and {[Cd2(μ7-ddba)(Hbpa)]·5H2O}n (8). The products 1–8 were generated from metal(II) chlorides, H5ddba, and various N-donor supporting ligands acting as mediators of crystallization (i.e., phen: 1,10-phenanthroline; 2,2′-bipy: 2,2′-bipyridine; 4,4′-bipy: 4,4′-bipyridine; H2biim: 2,2′-biimidazole; or bpa: bis(4-pyridyl)amine). All compounds were analyzed by standard methods (C/H/N analysis, FTIR, TGA and PXRD) including single-crystal X-ray diffraction. The structural multiplicity of 1–8 ranges from discrete dimers (1) or tetramers (3 and 4) to a 1D coordination polymer (2) and 3D metal–organic frameworks (5–8). Topological analysis of simplified H-bonded or metal–organic networks disclosed fcu (1), 2C1 (2), dia (3 and 4), sra (6), 3,4,7T3 (8), and unprecedented (5 and 7) topologies. The catalytic activity of 1–8 was investigated in a model Knoevenagel condensation between benzaldehydes and malononitrile, resulting in up to 99% yields of condensation products. The substrate scope, catalyst recycling, and effects of different reaction parameters were investigated. Finally, this work extends the use of H5ddba as an aromatic pentacarboxylate building block for the design of new metal–organic architectures with captivating structures and functional properties.

Membrane permeabilities to CO2 and HCO3 - constrain the function of CO2 concentrating mechanisms that algae use to supply inorganic carbon for photosynthesis. In diatoms and green algae, plasma membranes are moderately to highly permeable to CO2 but effectively impermeable to HCO3 - . Here, CO2 and HCO3 - membrane permeabilities were measured using an 18 O-exchange technique on two species of haptophyte algae, Emiliania huxleyi and Calcidiscus leptoporus, which showed that the plasma membranes of these species are also highly permeable to CO2 (0.006-0.02 cm · s-1 ) but minimally permeable to HCO3 - . Increased temperature and CO2 generally increased CO2 membrane permeabilities in both species, possibly due to changes in lipid composition or CO2 channel proteins. Changes in CO2 membrane permeabilities showed no association with the density of calcium carbonate coccoliths surrounding the cell, which could potentially impede passage of compounds. Haptophyte plasma-membrane permeabilities to CO2 were somewhat lower than those of diatoms but generally higher than membrane permeabilities of green algae. One caveat of these measurements is that the model used to interpret 18 O-exchange data assumes that carbonic anhydrase, which catalyzes 18 O-exchange, is homogeneously distributed in the cell. The implications of this assumption were tested using a two-compartment model with an inhomogeneous distribution of carbonic anhydrase to simulate 18 O-exchange data and then inferring plasma-membrane CO2 permeabilities from the simulated data. This analysis showed that the inferred plasma-membrane CO2 permeabilities are minimal estimates but should be quite accurate under most conditions.

To incorporate spintronics functionalities into two-dimensional devices, it is strongly desired to get two-dimensional electron gases (2DEGs) with high spin polarization. Unfortunately, the magnetic characteristics of the typical 2DEG at the LaAlO

Osteoarthritis (OA) is a degenerative joint disease, which can lead to joint pain, stiffness, deformity and dysfunction, that seriously affects the quality of life in patients. At present, the treatments of OA mainly include early pharmacological treatment and late joint replacement. However, current pharmacological treatment has limited efficacy and undesired side effects.Chitosan oligosaccharide (COS) is a kind of nontoxic and biodegradable oligo-saccharide, which is composed of 2-20 glucosamine or N-acetylglucosamine linked by β-1,4 glycosidic bond. Studies have shown that COS has significant biological properties like antimicrobial, anti-inflammatory, antioxidant, and anti-tumor, as well as immunoregulation ability. However, the effects of COS on OA have not been clarified. In this study, we explored the protective effects of COS with different degrees of deacetylation on chondrocytes stimulated by interleukin 1β (IL-1β) in vitro.The results showed that IL-1β inhibited cell proliferation and promoted cell apoptosis. Besides that, IL-1β increased the expression of the major chondro-degrading genes MMP13 and ADAMTS-5, while decreased the expression of COL2A and ACAN. COS with different degrees of deacetylation (HDACOS, MDACOS, LDACOS) had different effects on IL-1β induced inflammation. LDACOS had the most obvious anti-inflammatory effects to inhibit the expression of MMP13 and ADAMTS-5 while promoted the expression of COL2A and ACAN. In addition, we found that the expression of autophagy-related gene Beclin-1 was up-regulated, and the ratio of LC3-II/LC3-I was increased in the LDACOS group. Furthermore, transmission electron microscopy (TEM) analysis showed that the number of intracellular autophagosomes increased significantly with the treatment of LDACOS. Based on our research, we suggested that LDACOS could inhibit chondrocytes inflammation and promote cell autophagy, and might be a protective drug for the treatment of OA.

In a seminal work, Gozar et al. reported on the high-temperature interface superconductivity in bilayers of insulating La2CuO4 and metallic La2−xSrxCuO4 (x=0.45). An interesting question to address is how general and robust this interface superconductivity is. In the past, the cuprate bilayers were grown in a unique atomic-layer molecular beam epitaxy system, with a Sr doping range of x≤0.47, and the atomically flat interface was thought to be indispensable. Here, we have fabricated bilayers of La2CuO4 and La2−xSrxCuO4 by pulsed laser deposition. We have tried to extend the nominal doping range of Sr from the previous maximum of 0.47 to the present 1.70 (the nominal Sr content in the targets). X-ray diffraction result indicates that our La2−xSrxCuO4 films with x≤0.60 have very high crystalline quality; but the film crystalline structure degrades gradually with further increasing x, and finally the structure is fully lost when x reaches 1.40 and higher. Although the film quality scatters dramatically, our experiments show that there exists superconductivity for bilayers in nearly the entire over-doped Sr range, except for a non-superconducting region at x∼0.80. These observations demonstrate that the interface superconductivity in copper oxides is very general and robust.

N6-methyladenosine (m6A) is the one of the most important RNA modifications, playing the role of splicing events, mRNA exporting and stability to cell differentiation. Because of wide distribution of m6A in genes, identification of m6A sites in RNA sequences has significant importance for basic biomedical research and drug development. High-throughput laboratory methods are time consuming and costly. Nowadays, effective computational methods are much desirable because of its convenience and fast speed. Thus, in this article, we proposed a new method to improve the performance of the m6A prediction by using the combined features of deep features and original features with extreme gradient boosting optimized by particle swarm optimization (PXGB). The proposed PXGB algorithm uses three kinds of features, i.e., position-specific nucleotide propensity (PSNP), position-specific dinucleotide propensity (PSDP), and the traditional nucleotide composition (NC). By 10-fold cross validation, the performance of PXGB was measured with an AUC of 0.8390 and an MCC of 0.5234. Additionally, PXGB was compared with the existing methods, and the higher MCC and AUC of PXGB demonstrated that PXGB was effective to predict m6A sites. The predictor proposed in this study might help to predict more m6A sites and guide related experimental validation.

Compensated ferrimagnetic thulium iron garnet ceramics were prepared by the sol-gel method, which is significantly better than conventional solid-state reactions. Saturation magnetization yielded a maximum of 16.7 emu/g for specimens sintered at 900 °C. Subsequently, using the TmIG bulk as the target, an epitaxial film was grown by pulsed laser deposition. Furthermore, the spin transport properties of film with an attached 5 nm-thick platinum layer were studied in terms of longitudinal spin Seebeck effect (LSSE) and spin Hall magnetoresistance (SMR). The LSSE coefficient was as high as 0.38 μV/K and the SMR was 0.0072%. These results indicated that the bulk material and thin film presented excellent qualities, which are extremely important for the fundamental investigation of novel spin transport behaviour in compensated ferrimagnetic insulators. These results also provide more alternatives for spintronic materials.

Coccolithophores play important roles in marine biochemistry due to the processes of calcification and photosynthesis. Coccoliths are produced intracellularly, and cells produce coccoliths with stable isotopes distinct from theoretically precipitated inorganic calcite due to the influences of coccolithophore physiology, which are the so-called vital effects. The coccolith isotopic vital effects show large variations between species and hamper the use of coccolith isotopes in paleoceanography. In addition, learning the coccolith isotopic vital effects can help to better understand the carbon fractionation in coccolithophore cell, so as to provide a new insight in reconstructing sea water carbonate system (e.g., from alkenone δ 13 C or directly from coccolith δ 13 C) in geological past. In the present study, we investigated the morphological parameters, growth rate, and coccolith stable isotope compositions of Gephyrocapsa, the most universal alkenone-producing coccolithophore across the Pleistocene. These data allow us to estimate the influences of Gephyrocapsa morphology as well as the growth rate on coccolith vital effects. The results showed that Gephyrocapsa morphology, as well as coccolith isotopes, varied with species and morphotype changes, which were evolutionarily forced over the past 400 ka. The small Gephyrocapsa morphotypes (G. caribbeanica and Gephyrocapsa

Soft, stimulus-responsive 3D structures created from crosslinked poly(ionic liquid)s (PILs) have been fabricated at unprecedented sub-micron resolution by direct laser writing (DLW). These structures absorb considerable quantities of solvent ( e.g., water, alcohol, and acetone) to produce PIL hydrogels that exhibit stimulus-responsive behavior. Due to their flexibility and soft, responsive nature, these structures are much more akin to biological systems than the conventional, highly crosslinked, rigid structures typically produced using 2-photon polymerization (2-PP). These PIL gels expand/contract due to solvent uptake/release, and, by exploiting inherited properties of the ionic liquid monomer (ILM), thermo-responsive gels that exhibit reversible area change (30 ± 3%, n = 40) when the temperature is raised from 20 °C to 70 °C can be created. The effect is very rapid, with the response indistinguishable from the microcontroller heating rate of 7.4 °C s −1 . The presence of an endoskeleton-like framework within these structures influences movement arising from expansion/contraction and assists the retention of structural integrity during actuation cycling.

To investigate the effects of alpha-lipoic acid (LA) on the nutrition metabolism of sheep (36.72 ± 1.44 kg) in the summer, twenty-one sheep were randomly assigned to three treatments addressing LA supplementation: 0.00 (CTL), 600 (LA–L), and 900 (LA–H) mg/kg of dry matter (DM) per day for each sheep. Whole feces and urine collection methods were used to analyze apparent digestibility; ELISA kits to determine the hormones, antioxidant, and immune parameters in the blood; and serum metabolomics to detect and analyze small molecular substances. The results showed the DM intakes in the LA–L and LA–H groups were significantly increased by 8.22% and 8.02%, respectively, compared to that in the CTL group, and there was no significant effect on average daily gain, feed conversion ratio, nitrogen digestibility, calcium digestibility, and phosphorus digestibility. Regarding hormones, antioxidant, and immune indicators, the concentrations of triiodothyronine, superoxide dismutase, glutathione reductase, HSP70, and IgA significantly increased after LA supplementation, while adrenaline and malondialdehyde levels significantly decreased. With the pairwise comparison of the three groups, metabolomics analysis identified 22 differential metabolites in the positive/negative modes, respectively, which suggested LA supplementation can significantly affect sheep’s lipid, amino acid, and nucleic acid metabolism. Additionally, 3-indolepropionic acid, cinnamoylglycine, butyric acid, dodecanedioic acid, indoxyl sulfate, and pantothenic acid were the common differential metabolites with higher concentrations after LA supplementation. In summary, dietary supplementation of LA can increase the sheep’s DMI, energy digestibility, antioxidant capacity, and immunity. These changes provide evidence to support the use of LA supplementation for livestock.

A highly regioselective and stereoselective palladium-catalyzed addition reaction of indoles to glycals has been accomplished. This palladium-catalyzed chemistry provides a facile route to a variety of N-glycosyl indoles in high to excellent yields with β-selectivity. Remarkably, the reaction showed complete site selectivity toward the nitrogen of indole in a mild reaction condition.

Coccolithophores are a group of phytoplankton widely distributed in the ocean, which secrete extracellular calcite plates termed coccoliths. Coccoliths have been increasingly employed as an archive for geochemical, ecological and paleoclimate studies in recent years. A robust application of coccolith-based geochemical proxies relies on understanding the carbon acquisition strategies and the pathways of carbon supply for calcification. Carbonic anhydrase (CA) plays important roles in the carbon concentrating mechanism s of aquatic algae and potentially also in calcification. However, it is difficult to independently assess the role of CA in carbon supply for photosynthesis versus calcification. To fill this gap, we explored a new method to detect the CA activity inside coccolithophore. To achieve this, coccolithophores were cultured with oxygen and carbon isotope labeled dissolved inorganic carbon (DIC). By exploiting the different behavior of oxygen and carbon isotopes with (sea)water, this double label method can elucidate the significance of CA activity in the calcification pathway. Application of this method to Emiliania huxleyi shows that CA is present in the calcification pathway, and that there is no significant difference in the CA activity between a high and low CO2 treatment. However, under low CO2 treatment E. huxleyi enhanced the bicarbonate pumping rate on both cell and chloroplast membranes. This novel method could be performed on other species of coccolithophores in the future and have a potential to extend our knowledge on coccolith oxygen isotope vital effects. (© 2020 Elsevier ), Geochimica et Cosmochimica Acta, 292, ISSN:0016-7037, ISSN:1872-9533

This work demonstrates polymer brushes grafted from conductive polymer films which display dynamic surface switching dependent on salt, temperature and electrode potential. The electroactivity presented by the conductive polymer and the responsiveness of the grafted brushes leads to an interface with multiple control parameters. Here, we demonstrate this concept by grafting of uncharged brushes of poly(ethylene glycol)methyl ether methacrylates from conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT), and observe a temperature- and salt-induced switch of brush conformation, and their effect on the electrochemistry of the material. The switching conditions can be tailored by copolymerizing monomers with different numbers of ethylene glycol units. In addition, these surfaces exhibit antifouling properties, leading to potential applications such as electrically-addressable biointerfaces.

Being able to tune magnetic anisotropy (MA) by an electric field is crucial for the development of low-power magnetoelectric devices. The authors present an approach for tuning the MA of a manganite film by modulating the crystal phase of a cobaltite cap layer. By driving the cap layer to switch between SrCoO${}_{2.5}$ and SrCoO${}_{3\ensuremath{-}\ensuremath{\delta}}$ structures, reversible tuning of MA between two crystal directions was achieved for the manganite layer, accompanying a change in Mn $3d$ orbital occupancy. This work demonstrates indirect tuning of the magnetic easy axis of this highly spin-polarized manganite, providing guidance for constructing electrically tunable magnetoelectric devices.

Fault zones control the locations of many ore deposits, but the ore-forming processes in such fault zones are poorly understood. We have studied the deformation and ore textures associated with fault zones that controlled the lead–zinc mineralization of the Dongmozhazhua deposit, central Tibet, ∼100 km southwest of Yushu City. Geological mapping shows that the structural framework of the Dongmozhazhua area is defined by NW–SE-trending reverse faults and superposed folds that indicate at least two stages of deformation. The first stage is characterized by tight nearly E–W-striking folds that formed during the closure of the Jinshajiang Paleo-Tethyan Ocean in the Triassic. The second stage of deformation produced NW–SE-trending reverse faults and related structures of the Fenghuoshan–Nangqian fold-and-thrust belt associated with India–Asia collision in the late Eocene to Oligocene. Scanline surveys along the ore-controlling fault zones show an internal structure that comprises a damage zone, a breccia zone with clasts that have become rounded, and a breccia zone with lenticular clasts, and this complex architecture was formed during at least two compressional substages of deformation. The Pb–Zn mineralization in the Dongmozhazhua area occurs exclusively close to NW–SE-trending reverse fault zones. Microtextural observations reveal that mineralization occurred as veinlets and disseminated blebs in limestone clasts, and as continuous bands and cements in fractured rocks. Cataclastic sulfide grains also can be seen in the matrix of some fault zones. The types of mineralization differ with structural position. The fillings of the ore-bearing veinlets typify the products of hydraulic fracture and both types of mineralization took place concurrently with regional contraction. We consider, therefore, that the ore-bearing fluids in the Dongmozhazhua deposit were concentrated in fault zones during regional compression and that the ore minerals were precipitated during hydraulic fracturing of host rocks. Subsequent fault activity pulverized some pre-existing sulfide material into cataclastic grains in the matrix of a tectonic breccia that developed in the same faults.

Two-dimensional electron gas (2DEG) at the perovskite oxide interface exhibits a lot of exotic properties, presenting a promising platform for the exploration of emergent phenomena. While most of the previous works focused on SrTiO3-based 2DEG, here we report on the fabrication of high-quality 2DEGs by growing an amorphous LaAlO3 layer on a (001)-orientated KTaO3 substrate, which is a 5d metal oxide with a polar surface, at a high temperature that is usually adopted for crystalline LaAlO3. Metallic 2DEGs with a Hall mobility as high as ∼2150 cm2/(V s) and a sheet carrier density as low as 2 × 1012 cm–2 are obtained. For the first time, the gating effect on the transport process is studied, and its influence on spin relaxation and inelastic and elastic scattering is determined. Remarkably, the spin relaxation time can be strongly tuned by a back gate. It is reduced by a factor of ∼69 while the gate voltage is swept from −25 to +100 V. The mechanism that dominates the spin relaxation is elucidated.

LiMn0·75Fe0·25PO4/C powders were prepared by a facile hydrothermal and ball-milling method, and then calcined. X-ray diffraction and scanning electron microscopy revealed that the calcination temperature had a strong effect on the structure and morphology of the as-prepared powder, and thus, on the subsequent electrochemical performance of the material. When the calcination temperature was increased from 550 to 700°C, the grain size of LiMn0·75Fe0·25PO4/C increased greatly. The electronic conductivities of the carbon coatings, which were obtained from sucrose and calcined at 550 and 700°C, were investigated. The discharge capacities of LiMn0·75Fe0·25PO4/C decreased with increasing calcination temperature, but electrochemical impedance spectroscopy showed that the charge-transfer resistances of LiMn0·75Fe0·25PO4/C electrodes decreased owing to the increase in the electronic conductivity of the carbon coating. Grain growth played a more important role than the electronic conductivity of the carbon c...

With the aid of density functional theory (DFT) calculations, we have studied the mechanisms and stereoselectivities in PPh 3 -catalyzed intermolecular Rauhut-Currier reaction of N -phenylmaleimide ( R 1 ) and 2-benzoyl acrylate ( R 2 ). Various reaction pathways in the absence and presence of benzoic acid ( PhCO 2 H ) were investigated. Comparing the overall reaction barriers based on mechanism A (in the absence of PhCO 2 H ) and mechanism B (in the presence of PhCO 2 H ), we were able to understand the critical role of PhCO 2 H . The preferred mechanism (mechanism B) initiates nucleophilic conjugated addition of PPh 3 to R 1 to form a zwitterionic intermediate B_1 ( first step ). It then reacts with R 2 to generate intermediate B_2 ( second step ). The following intramolecular proton transfer is shown to occur via two successive H-shift processes with the assistance of PhCO 2 H : the C5 atom of B_2 first abstracts a proton from PhCO 2 H to generate B_3 , then the H atom transfers from C3 to the PhCOO − group completes the intramolecular proton transfer and produces B_4 ( third step ). Finally, the catalyst PPh 3 releases from B_4 affording the cross-coupling product ( fourth step ). On the basis of our calculation results, path D leading to the S-configuration product P(S) is the most energy favorable pathway among the eight possible stereoselective pathways. The second step is found to be the rate- and stereoselectivity-determining step with an overall free energy barrier of 21.3 kcal/mol. Our DFT results are in good agreement with experimental observations. The present study should be valuable for understanding this kind of reaction.

Manipulation of oxygen vacancies via electric-field-controlled ionic liquid gating has been reported in many model systems within the emergent fields of oxide electronics and iontronics. It is then significant to investigate the oxygen vacancy formation/annihilation and migration across an additional ferroelectric layer with ionic liquid gating. Here, we report that via a combination of ionic liquid and ferroelectric gating, the remote control of oxygen vacancies and magnetic phase transition can be achieved in SrCoO

The force required to detach a single fibroblast cell in contact with the conducting polymer, polypyrrole doped with dodecylbenzene, was quantified using the Atomic Force Microscope-based technique, Single Cell Force Spectroscopy. The de-adhesion force for a single cell was 0.64 ± 0.03 nN and predominately due to unbinding of α5β1 integrin complexes with surface adsorbed fibronectin, as confirmed by blocking experiments using antibodies. Monophasic pulsed stimulation (50 μs pulse duration) superimposed on either an applied oxidation (+500) or reduction (−500 mV) constant voltage caused a significant decrease in the de-adhesion force by 30%–45% to values ranging from 0.34 to 0.43 nN (±0.02 nN). The electrical stimulation caused a reduction in the molecular-level jump and plateau interactions, while an opposing increase in nonspecific interactions was observed during the cell de-adhesion process. Due to the monophasic pulsed stimulation, there is an apparent change or weakening of the cell membrane properties, which is suggested to play a role in reducing the cell de-adhesion. Based on this study, pulsed stimulation with optimized threshold parameters represents a possible approach to tune cell interactions and adhesion on conducting polymers.The force required to detach a single fibroblast cell in contact with the conducting polymer, polypyrrole doped with dodecylbenzene, was quantified using the Atomic Force Microscope-based technique, Single Cell Force Spectroscopy. The de-adhesion force for a single cell was 0.64 ± 0.03 nN and predominately due to unbinding of α5β1 integrin complexes with surface adsorbed fibronectin, as confirmed by blocking experiments using antibodies. Monophasic pulsed stimulation (50 μs pulse duration) superimposed on either an applied oxidation (+500) or reduction (−500 mV) constant voltage caused a significant decrease in the de-adhesion force by 30%–45% to values ranging from 0.34 to 0.43 nN (±0.02 nN). The electrical stimulation caused a reduction in the molecular-level jump and plateau interactions, while an opposing increase in nonspecific interactions was observed during the cell de-adhesion process. Due to the monophasic pulsed stimulation, there is an apparent change or weakening of the cell membrane properti...

The Xiejiagou deposit is a representative medium-sized gold deposit in Jiaodong the Peninsula, which contains gold reserves of 37.5 t. The orebodies are hosted in the Linglong biotite granite with a zircon LA-ICP-MS U–Pb age of 160.5±1.3 Ma (N=15, MSWD=1.2) and are characterized by disseminated- or stockwork-style ores. Mineralization and alteration are structurally controlled by the NE-striking fault. Three stages of mineralization were identified with the early stage being represented by (K-feldspar) sericite quartz pyrite, the middle stage by quartz gold polymetallic sulfide, and the late stage by quartz carbonate. Ore minerals and gold mainly occurred in the middle stage. Three types of primary fluid inclusions were distinguished in the Xiejiagou deposit, including carbonic-aqueous, pure carbonic, and aqueous inclusions. The primary fluid inclusions of the three stages were mainly homogenized at temperatures of 262–386°C, 192–347°C, and 137–231°C, with salinities of 2.22–8.82, 1.02–11.60, and 1.22–7.72 wt% NaCl equivalent, respectively. These data indicate that the initial ore-forming fluids were a medium temperature, CO2-rich, and low-salinity H2O–CO2–NaCl homogeneous system, and the ore-forming system evolved from a CO2-rich mesothermal fluid into a CO2-poor fluid. Considering the fluid inclusion characteristics, H–O–S–Pb isotopes, and regional geological events, the ore-forming fluid reservoir was likely metamorphic in origin. Trapping pressures of the first two hydrothermal stages estimated from the carbonic aqueous inclusion assemblages were ~224–302 MPa and ~191–258 MPa, respectively. This suggests that the gold mineralization of the Xiejiagou gold deposit occurred at a lithostatic depth of ~7.2–9.7 km. Au(HS)2− was the most probable gold-transporting complex at the Xiejiagou deposit. Precipitation of gold was caused by a CO2 effervescence of initial auriferous fluids.

Mycotoxin contamination is an important cause of food and feed safety issues. Mycotoxin contaminated foods can cause acute or chronic poisoning, and even cause cancers in humans and animals. Technology that can rapidly and quantitatively detect mycotoxins is of great importance for ensuring food safety and economic development. This chapter presents mycotoxins and their hazards, and introduces UPT-POCT for detection of mycotoxins. Comparisons of UPT-POCT and other detection methods are discussed in terms of both the methodology and practical applications. The results demonstrate that UPT-POCT is a promising tool for rapid, sensitive, and quantitative detection of mycotoxins in the field.

The metallic interface between two oxide insulators, such as LaAlO3/SrTiO3 (LAO/STO), provides new opportunities for electronics and spintronics. However, due to the presence of multiple orbital populations, tailoring the interfacial properties such as the ground state and metal-insulator transitions remains challenging. Here, we report an unforeseen tunability of the phase diagram of LAO/STO by alloying LAO with a ferromagnetic LaMnO3 insulator without forming lattice disorder and at the same time without changing the polarity of the system. By increasing the Mn-doping level, x, of LaAl1-xMnxO3/STO, the interface undergoes a Lifshitz transition at x = 0.225 across a critical carrier density of nc= 2.8E13 cm-2, where a peak TSC =255 mK of superconducting transition temperature is observed. Moreover, the LaAl1-xMnxO3 turns ferromagnetic at x >=0.25. Remarkably, at x = 0.3, where the metallic interface is populated by only dxy electrons and just before it becomes insulating, we achieve reproducibly a same device with both signatures of superconductivity and clear anomalous Hall effect. This provides a unique and effective way to tailor oxide interfaces for designing on-demand electronic and spintronic devices., 18 pages and 6 figures

Manipulating topotactic phase transformations via orderly ion transfer in complex oxides ABOx is ubiquitous in advanced applications such as ionotronics, ion-batteries and catalysts. Most of such ion-mediated transformations are accomplished by the transfer of oxygen or A-site ions. However, implementing the transformation via the transfer of B-site ions, despite the great challenge to overcome a large cohesive energy, has unique advantage since they host most functional properties of materials. Here, we present a tri-state phase transformation from perovskite (P) to brownmillerite (BM) and to single-layered perovskite (SL) structure via the concerted migration of oxygen and B-site Co-ions in La0.7Sr0.3CoO3 thin films. Ac-STEM, XPS, XAS, PNR, magnetic and electric measurements demonstrated that presented B-site Co-cation transfer is along the CoO4 tetrahedral sub-layer of the BM film, which leads to the reconfiguration of 3d-electrons and spin state in remanent Co ions and causes tremendous changes in magnetic and electric properties: from canted-antiferromagnetic insulator in BM phase to ferromagnetic insulator in SL phase. First-principles calculations revealed that the La3+-doping at A-site largely reduces the cohesive energy of Co-ions in CoO4 and destabilize the CoO4 tetrahedron of BM phase, which explains the formation of Co-ions transfer channel in the CoO4 tetrahedral sub-layer. The present study highlights the effectiveness of regulating topotactic transformation via B-site ions transfer and provides a new pathway for manipulating the topotactic transformation with diverse functionalities.

Structural and magnetic properties of the LaCoO3/SrTiO3 (LCO/STO) multilayers (MLs) with a fixed STO layer of 4 nm but varied LCO layer thicknesses have been systematically studied. The MLs grown on Sr0.7La0.3Al0.65Ta0.35O3 (LSAT) and SrTiO3 (STO) exhibit the in-plane lattice constant of the substrates, but those on LaAlO3 (LAO) show the in-plane lattice constant between those of the first two kinds of MLs. Compared with the LCO single layer (SL), the magnetic order of the MLs is significantly enhanced, as demonstrated by a very slow decrease, which is fast for the SL, of the Curie temperature and the saturation magnetization as the LCO layer thickness decreases. For example, clear ferromagnetic order is observed in the ML with the LCO layer of ∼1.5 nm, whereas it vanishes below ∼6 nm for the LCO SL. This result is consistent with the observation that the dark stripes, which are believed to be closely related to the magnetic order, remain clear in the MLs while they are vague in the corresponding LCO SL. The present work suggests a novel route to tune the magnetism of perovskite oxide films.

A new core structure-motivated strategy for the intramolecular aromatic spiroketalization process was found and used for the enantioselective synthesis of bisbenzannulated spiroketals, the bioactive core of rubromycins, with high levels of enantioselectivity (up to 98% ee) via an organohalogenite-mediated asymmetric intramolecular aromatic spiroketalization. This is the first organocatalytic method for the construction of optically pure bisbenzannulated spiroketals.

Conductive colloidal probe Atomic Force-Scanning Electrochemical Microscopy (AFM-SECM) is a new approach, which employs electrically insulated AFM probes except for a gold-coated colloid located at the end of the cantilever. Hence, force measurements can be performed while biasing the conductive colloid under physiological conditions. Moreover, such colloids can be modified by electrochemical polymerization resulting, e.g. in conductive polymer-coated spheres, which in addition may be loaded with specific dopants. In contrast to other AFM-based single cell force spectroscopy measurements, these probes allow adhesion measurements at the cell–biomaterial interface on multiple cells in a rapid manner while the properties of the polymer can be changed by applying a bias. In addition, spatially resolved electrochemical information e.g., oxygen reduction can be obtained simultaneously. Conductive colloid AFM-SECM probes modified with poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT:PSS) are used for single cell force measurements in mouse fibroblasts and single cell interactions are investigated as a function of the applied potential.

Baiyangping Pb–Zn–Cu–Ag deposit is located in Lanping basin, northwestern Yunnan province. The deposit is composed of a few ore veins and can be divided into several ore blocks. The ore bodies are primarily hosted in Mesozoic carbonate, sandstone and siltstone along the north–south-striking, NWW-striking and NE–SW-striking fault zones. There are breccia, massive, vein like and disseminated ores. The main ore minerals are sphalerite, galena, gratonite, jordanite, tetrahedrite series minerals, chalcocite, chalcopyrite, realgar, orpiment, bournonite, cobalt-bearing arsenopyrite, argentite, kongsbergite, cobaltine, siegenite. The sizes of fluid inclusions in Baiyangping deposit are generally less than 10 μm and have the shape of round, oval, irregular, etc. The ore-forming fluid system is Ca 2+ –Na + –K + –Mg 2+ –Cl − –F − –NO 3 − brine system. The freezing temperature of fluid inclusions in mineral deposits ranges from −26.4 to −0.2 °C, average −14.6 °C; the homogenization temperature is concentrated in 120–180 °C, and the salinity is between 0.35 and 24.73 wt% (NaCl eq ), average 16.9 wt% (NaCl eq ). δ 13 C PDB and δ 18 O SMOW values of hydrothermal calcite range from −4.16‰ to 3‰ and −2.5‰ to 20.4‰, respectively. δ 34 S values of sulfide minerals range from −10.2‰ to 11.2‰, average 5.6‰. The sulfide samples yield 206 Pb/ 204 Pb values of 18.609–18.818, 207 Pb/ 204 Pb of 15.548–15.842 and 208 Pb/ 204 Pb = 38.514–39.556. C–O–S–Pb isotope compositions of the Baiyangping deposit indicate a homogeneous carbon source, and the carbon in hydrothermal calcite is derived from the dissolution of carbonate rock strata, the ore-forming fluid belongs to basin brine fluid system, which is mixed with the precipitate water, sulfur in sulfides and sulfosalts is derived from thermal chemical sulfate reduction, and the thermal decomposition of sulfur-bearing organic matter. The metal mineralization material is from sedimentary strata and basement. The late Pb–Zn polymetallic mineralization event superposed within early Cu–Co polymetallic mineralization event resulted in the differences of ore-forming elements for Baiyangping deposit.

A significant belt of carbonate-hosted Pb–Zn mineralization occurs in the Himalayan–Zagros collisional orogenic system. Three differing types of these Pb–Zn deposits within this belt have been identified based on variations in gangue mineral assemblages, leading to the classification of carbonate-, quartz- and fluorite-rich classes of Pb–Zn deposits. The third Pb–Zn mineralization (fluorite-rich) type is common in this orogenic system, but little research has been undertaken on it. Here, we focus on the Mohailaheng deposit, a large-sized fluorite-rich carbonate-hosted Pb–Zn deposit (> 100 Mt Pb + Zn ores with average grade of 2.18%–4.23%); the deposit is located in the Sanjiang Cenozoic thrust-fold belt, an important part of the Himalayan–Zagros collisional orogenic system and an area that formed during the early Tertiary India–Eurasia collision. The main orebodies in this deposit are stratabound and are hosted by Carboniferous limestones that are located along secondary faults associated with a regional thrust fault. The main assemblage is a sphalerite + galena + pyrite sulfide assemblage associated with a calcite + fluorite + barite + quartz + dolomite gangue assemblage. Detailed field and experimental work indicates that the deposit formed during three distinct phases of hydrothermal activity. Studies on fluid inclusion and stable isotopes of gangue minerals indicate that two dominant distinct fluids involving the deposit formation. They include (1) a low-temperature (130–140 °C), high-salinity (23–24 wt.% NaCl equivalent) basinal brine containing Na + –K + –Mg 2 + –Ca 2 + –Cl − ions and abnormally high SO 4 2 − concentrations, which probably derived from Tertiary basins in the regional district, and (2) a low- to moderate-temperature (170–180 °C) and moderate- to high-salinity (19–20 wt.% NaCl equivalent) metamorphic fluid containing Na + –K + –Mg 2 + –Cl – –SO 4 2 − ions and abnormally high F − and organic matter concentrations, that probably formed during regional metamorphism. Some evaporated seawaters and meteoric fluids were also identified in mixtures with these two dominant fluids. The Pb–Zn mineralization at Mohailaheng formed during three distinct stages, consistent with the regional tectonic history. The first stage involved the formation of favorable lithological and structural traps at Mohailaheng during regional thrusting, leading to the migration of compressed metamorphic waters at depth along a detachment zone, sequestering metals from sediments within the region. Basinal brines at the surface also began to infiltrate down along the secondary faults, dissolving gypsum from the underlying sediments. The second stage was associated with the cessation of thrusting and the onset of strike-slip movements along these thrust faults. Metamorphic fluids containing high concentrations of halogen ions, organic gases, and metals ascended into the structural traps at Mohailaheng along the reactivated thrust faults, causing fluorite, calcite, and some sulfide precipitation. Then, basinal brines rich in SO 4 2 − quickly descended into the structural traps along the reactivated faults, causing reduction of SO 4 2 − by organic matter, and producing significant amounts of H 2 S. The reduced sulfur then reacted with the metals in the fluids, causing significant sulfide precipitation. The third stage was associated with metal-depleted fluids, which only resulted in the precipitation of calcite from the diluted basinal brines. Combining these findings with research results on other fluorite-rich carbonate-hosted Pb–Zn deposits in the Himalayan–Zagros orogenic system suggests that this type of carbonate-hosted Pb–Zn deposits can also be classified as Mississippi Valley-type (MVT) deposits, and that the origin of the fluorite in these deposits may be related to multiple hydrothermal fluids involved in the mineralization evolution.

Two-dimensional electron gases (2DEGs) at oxide interfaces, which provide unique playgrounds for emergent phenomena, have attracted increasing attention in recent years. While most of the previous works focused on the 2DEGs at ${\mathrm{LaAlO}}_{3}/{\mathrm{SrTiO}}_{3}$ interfaces, here we report on a new kind of 2DEGs formed between a magnetic insulator EuO and a high-$k$ perovskite ${\mathrm{KTaO}}_{3}$. The 2DEGs are not only highly conducting, with a maximal Hall mobility of $111.6\text{ }\text{ }{\mathrm{cm}}^{2}/\mathrm{V}\text{ }\mathrm{s}$ at 2 K, but also well spin polarized, showing strongly hysteretic magnetoresistance up to 25 K and well-defined anomalous Hall effect up to 70 K. Moreover, unambiguous correspondences between the hysteretic behaviors of 2DEGs and the EuO layer are captured, suggesting the proximity effect of the latter on the former. This is confirmed by the results of density-functional theory calculations: Through interlayer exchange, EuO drives the neighboring ${\mathrm{TaO}}_{2}$ layer into a ferromagnetic state. The present work opens new avenues for the exploration for high performance spin-polarized 2DEGs at oxide interfaces.

Cell adhesion on conducting polymers is important in organic bioelectronics, including applications such as electronically switchable surfaces and electrochemical transistors. There is a fundamental interest in understanding the conducting polymer–cellular interface though as yet no direct measurements to quantify the cell adhesion forces and energies, particularly at the molecular level, have been undertaken. Here, the authors apply electrochemical-single cell force spectroscopy (EC-SCFS) to directly quantify the de-adhesion forces between single L929 fibroblast cells and polypyrrole doped with dodecylbenzene sulfonate (PPy–DBSA) under electrical stimulation. The EC-SCFS reveals single cell de-adhesion forces of 0.65 nN on PPy–DBSA films with adsorbed fibronectin (FN) protein. Blocking experiments by introducing antibodies show that cell de-adhesion is largely due to the binding (∼60% of interactions) of cell-surface α5β1 integrin receptors. Electrochemical oxidation and reduction of PPy–DBSA during initial adsorption of fibronectin cause a significant decrease in the single cell de-adhesion forces to ∼0.4 nN, which is suggested to relate to electrical stimulation effects on reducing FN adsorption on the polymer. In contrast, when electrical stimulation is applied after protein adsorption is established and during the EC-SCFS measurements, the single cell de-adhesion is significantly enhanced on the oxidized polymer compared to the reduced and nonbiased polymer. The study highlights the use of EC-SCFS to directly quantify cell adhesion on electrode surfaces, as well as the ability to probe molecular-level interactions such as integrin receptor–FN complexes with forces of ∼50–100 pN.

Chemical redox reaction can lead to a two-dimensional electron gas (2DEG) at the interface between a TiO2-terminated SrTiO3 (STO) substrate and an amorphous LaAlO3 (a-LAO) capping layer. When replacing the STO substrate with rutile and anatase TiO2 substrates, considerable differences in interfacial conduction are observed. Based on X-ray photoelectron spectroscopy (XPS) and transport measurements, we conclude that the interfacial conduction comes from redox reactions, and that the differences among the materials systems result mainly from variations in the activation energies for the diffusion of oxygen vacancies at substrate surfaces.

p-type transparent conductive Ca3Co4O9 thin films were grown on LaAlO3 substrates using a pulsed laser deposition technique. The films showed perfect c-axis orientation with a resistivity of about 7.3 mΩ cm at room temperature and optical transmittance of about 50% in the visible range. A high figure of merit of about 988 MΩ−1 was achieved in these c-axis oriented Ca3Co4O9 films, which is comparable to those reported for the state-of-the-art p-type transparent conducting oxides. This work demonstrated the potential applications of c-axis oriented Ca3Co4O9 films in optoelectronic devices as a new class of transparent conducting oxide coatings.

Reported here is a water-soluble ligand, N-(sulfoethyl)-iminodiacetic acid (H3SEIDA), used for the complexation of uranyl ions. A coordination compound composed of uranyl cation and N-(sulfonatoethyl)-ammoniodiacetate (SEADA2−) zwitterion was synthesized from an acidic aqueous solution. This compound features a 2D undulating fes (4.82) coordination layer that is stacked and linked by hydrogen-bonding interaction to form a 3D supramolecular framework with a 1D larger-cycle channel. Thermal analysis demonstrates the relatively weak bonding between uranyl cation and SEADA2− zwitterion. The monomeric uranyl-based fluorescence emission is red-shifted by about 5 nm compared to that of uranyl nitrate hexahydrate. The hydrothermal synthesis of this uranyl compound was successfully applied to the sequestration of uranyl ions.

Four hyperbranched polysiloxanes (HPSis) with different molecular weights and concentration ratios of double bonds to epoxy groups (1:6.5–1:0.7) were synthesized and characterized. Each HPSi was facilely grafted onto surfaces of Kevlar fibers (KFs) to develop novel modified fibers (HPSi-g-KFs). The structures and integrated properties of HPSi-g-KFs as well as the origin behind were systematically investigated. Results show that HPSi-g-KFs have much rougher surface morphologies, and their surface free energies are as high as about 1.7 times that of KFs, showing greatly improved wettability. Besides, HPSi-g-KFs have excellent UV resistance after 168 h UV irradiation, the retentions of tenacity, energy to break, modulus and break extension are as high as 92, 86, 95 and 96%, respectively, while those of KFs are 66–85%. In addition, compared with KFs, HPSi-g-KFs have higher tensile tenacity and energy to break with similar modulus and break extension, much better thermal stability and flame retardancy. The nature of HPSi has different influence on different property of fibers, the HPSi with smaller molecular weight and more epoxy groups is beneficial to prepare HPSi-g-KFs with better wettability, while that with larger molecular weight and more double bonds tends to prepare HPSi-g-KF with better flame retardancy and UV resistance.

Different metal ions were added as supplements to culture media to study sophorolipids production by Wickerhamiella domercqiae Y2A CGMCC 3798. The fermentation media were supplemented with different metal ions in the form of sulfate. A maximum yield 149.90 g/L was achieved in the presence of Cu2+ ions. The production of lactonic sophorolipids was favored when culture media wad supplied with Mg2+ ions, while Fe2+ ions were the optimal ions for acidic sophorolipids production. TLC, HPLC, and LC–MS analyses were used for further investigation on the sophorolipids production. The results of SDS–PAGE and enzymatic transformation of acidic sophorolipids showed differential expression of extracellular proteins of W. domercqiae Y2A CGMCC 3798 in presence of Mg2+ or Fe2+. Overall the results indicated potential selective production of different sophorolipids based on selected metal ions in culture media. Practical applications: During the fermentation process of sophorolipids, L-SLs and A-SLs were produced selectively by adding Mg2+ and Fe2+into fermentation media, respectively. Sophorolipid composition and production are different produced by Wickerhamiella domercqiae Y2A CGMCC 3798 cultured with Mg2+ (a) and Fe2+ (b), respectively by HPLC analysis.

A direct asymmetric tandem reaction of alpha-nitro ketones with beta,gamma-unsaturated alpha-ketoesters was found to be catalyzed by a bifunctional rosin-derived thiourea and gave 5-nitro-2-actoxy1-2-pentenates in excellent ee values and yields, a much better result than previously reported. Furthermore, through theoretical analysis, literature research and experimental verifications, a new mechanism involving an inverse-electron-demand Diels-Alder (IEDDAR) and a retro-Henry reaction was proposed. (C) 2014 Yu Tang and Ying Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

In this work, we have developed an ion exchange reaction to fabricate homogeneously distributed CdS nanoparticles with a size in the range of 20–120 nm in the sulphonated poly(ether ether ketone) (SPEEK) membrane. The chemical composition of the composite membrane was characterised by ultraviolet-visible (UV-vis) spectroscopy, powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements. The as prepared SPEEK/CdS composite membrane exhibited a remarkable photocatalytic activity towards the photodegradation of rhodamine B under visible light irradiation at room temperature. This work presents a simple and versatile approach to prepare sulphide nanostructures on the surface of polymer membrane, providing a new opportunity for their applications in the photocatalytic reaction.

Simultaneously overcoming the poor UV resistance and surface inertness of aramid fibers while maintaining their excellent mechanical and thermal properties is a challenge. New grafted Kevlar fibers (HSi-g-KFs) were facilely prepared by in situ synthesizing hyperbranched polysiloxane with double bonds and epoxy groups on Kevlar fibers (KFs). As the molar ratio of water to silane was adjusted from 1.1 to 1.4, the surface morphology of HSi-g-KFs successively changed from unconnected dots to condensed dots and to a compact coating of hyperbranched polysiloxane. Compared with KFs, all HSi-g-KFs were found to have remarkably improved surface wettability and UV resistance. After 168 h of UV irradiation, the retentions of the modulus and break extension of the HSi-g-KFs were as high as 95–97%. In addition, the HSi-g-KFs were found to have much higher thermal stabilities than KFs. These attractive results demonstrate that the method proposed herein is a new and facile approach for preparing high-performance aramid...

A novel formal asymmetric synthesis of (-)-triptonide and (-)-triptolide, featuring a new alternative access to their known key intermediate 4, has been achieved through two synthetic routes in 9 steps with 13.6% total yield and 10 steps with 18.5% overall yield, respectively. This synthesis is scalable and hence has high potential for application to further synthetic elaboration and biologic investigation on such natural products.

Evaluating carbonate dissolution in deep sea sediments is of key importance in understanding the variation of the carbonate compensation depth and the ocean carbon cycle in the geological past. Since coccoliths are one of the main contributors to oceanic CaCO3, their dissolution and preservation degrees in sediments can be a useful indicator for deep sea carbonate chemistry. Varying coccolith preservation conditions have been found due to dissolution caused by organic matter degradation in the recent surface sediments of the East China Sea, which provides a good basis for the study of coccolith morphological and assemblage responses to dissolution. We measured the coccolith weight, thickness, and length of Gephyrocapsa spp. (>3 μm) using a circularly polarized light microscope. It has been found that Gephyrocapsa spp. (>3 μm) coccoliths become thinner and lighter in response to dissolution, and coccolith assemblages are also altered in poorly preserved sediments. This phenomenon was confirmed by an acidification experiment on a sediment sample, which also showed that coccoliths became thinner and lighter under increasingly acidified conditions. There is selective dissolution, i.e., Emiliania huxleyi coccoliths are most dissolution-prone, followed by Gephyrocapsa spp. ( 3 μm), and Helicosphaera spp.. Coccolith morphological parameters can be used to quantitatively evaluate coccolith preservation and dissolution in sediment samples. We suggest that using size-normalized weight, a mean coccolith weight loss of ~30–50% can be assigned to moderate-poor preservation for coccoliths, as reflected by the measured coccolith morphological changes in the surface sediments and in the acidification experiment.

In 2014, the International Ocean Discovery Program (IODP) Expedition (Exp.) 349 discovered carbonate layers at sites located in the South China Sea (SCS) central basin. Preliminary results from shipboard investigation showed that most of these carbonate layers are calcareous nannofossil ooze and interpreted them as turbidites. However, more detailed studies are required to determine their depositional mechanisms and paleoenvironmental implications. In this study, we have analyzed CaCO3 content, calcareous nannofossil abundance, assemblage composition and preservation in carbonate and clay samples from the upper Miocene sections of Site U1433 in the SCS central basin. We confirm that these carbonate layers are of turbidity current genesis but are not typical nannofossil ooze, while the clays represent regular in situ deep sea sediments. The study interval spanned approximately from 10 to 5 million years before present (Ma). Calcareous nannofossil abundance and assemblage are used to reconstruct the evolution of the upper seawater structure in the SCS central basin. Our results indicate that the seawater shifted from strongly stratified to well-mixed due to enhanced monsoon. This shift was accompanied by an increase in pelagic productivity at ~8 Ma. This environmental change is critical for component variations of the carbonate turbidites since we suggest that these turbidites mainly sourced from periplatform ooze in the southern SCS composed by of mixed neritic and pelagic particles. The neritic and pelagic CaCO3 production have inversed responses to the change of seawater environment in the SCS and thus cause the component variations in the carbonate turbidites of Site U1433.

Recently, a high mobility quasi-two-dimensional electron gas has been reported for the heterointerface between two insulating and nonmagnetic oxides of spinel γ-Al2O3 and perovskite SrTiO3 (STO). Herein, we fabricated the epitaxial heterostructure with Al-based magnetic spinel oxide MAl2O4 (M = Fe, Co, Ni) on perovskite STO. Remarkably, all the MAl2O4 (M = Fe, Co, Ni) films exhibit ferromagnetic behavior up to room temperature. Although FeAl2O4/STO is insulating, the NiAl2O4/STO and CoAl2O4/STO heterointerfaces are found to be highly metallic and exhibit the anomalous Hall effect (AHE) at temperatures below 30 K. Their Hall mobility is as high as 3 × 104 cm2 V−1 s−1, comparable to that of the γ-Al2O3/STO interface. There has been evidence of oxygen-vacancy-related magnetism in γ-Al2O3/STO at temperatures below 5 K, while the enhanced AHE in NiAl2O4/STO and CoAl2O4/STO likely comes from the magnetic proximity effect induced by the top ferromagnetic MAl2O4 spinel films.Recently, a high mobility quasi-two-dimensional electron gas has been reported for the heterointerface between two insulating and nonmagnetic oxides of spinel γ-Al2O3 and perovskite SrTiO3 (STO). Herein, we fabricated the epitaxial heterostructure with Al-based magnetic spinel oxide MAl2O4 (M = Fe, Co, Ni) on perovskite STO. Remarkably, all the MAl2O4 (M = Fe, Co, Ni) films exhibit ferromagnetic behavior up to room temperature. Although FeAl2O4/STO is insulating, the NiAl2O4/STO and CoAl2O4/STO heterointerfaces are found to be highly metallic and exhibit the anomalous Hall effect (AHE) at temperatures below 30 K. Their Hall mobility is as high as 3 × 104 cm2 V−1 s−1, comparable to that of the γ-Al2O3/STO interface. There has been evidence of oxygen-vacancy-related magnetism in γ-Al2O3/STO at temperatures below 5 K, while the enhanced AHE in NiAl2O4/STO and CoAl2O4/STO likely comes from the magnetic proximity effect induced by the top ferromagnetic MAl2O4 spinel films.

A new core structure-motivated strategy for the intramolecular aromatic spiroketalization process was found and used for the enantioselective synthesis of bisbenzannulated spiroketals, the bioactive core of rubromycins, with high levels of enantioselectivity (up to 98% ee) via an organohalogenite-mediated asymmetric intramolecular aromatic spiroketalization. This is the first organocatalytic method for the construction of optically pure bisbenzannulated spiroketals.