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Semiconducting single-walled carbon nanotube (s-SWCNT) films require high-quality preparation and optimization for use in carbon-based electronic devices. Tremendous progress has been made in s-SWCNTs sorting technology with conjugated polymers to obtain high-purity s-SWCNT films. However, one drawback of this technology is residual polymer wrapping on s-SWCNT surfaces. These residual polymers have poor conductivity, impeding the charge transport between the nanotube-electrode and the nanotube-nanotube. To address this issue, a rapid annealing and cooling method was developed for cleaning the s-SWCNT films, which can thoroughly remove the wrapped polymers from the surfaces of s-SWCNTs, effectively reducing the contact resistance between the nanotube-metal electrode and the nanotube-nanotube. Our results show that thin-film transistors made of cleaned s-SWCNTs exhibited improved performance when compared with pristine s-SWCNT films rinsed with an organic solvent. The contact resistance between the s-SWCNTs and the electrode was reduced by 700%, while the on–state current density of the CNT-TFTs increased by nearly 600%. These results thus demonstrated the effectiveness of our developed method for removing polymers from the surfaces of s-SWCNTs, which is essential for the further development of carbon nanotube electronic devices and circuits.

A new and convenient copper-catalyzed synthesis of alkyl sulfides has been accomplished using S-alkyl butanethioate as a thiol source. This catalytic protocol displayed a good functional groups tol...

This study aims to predict the productivity of an open-hole horizontal gas well (OHHGW) in a gas reservoir with closed bottom and top boundaries (GRCBTBs). First, according to the theory of mirror imaging, an OHHGW in GRCBTBs is transformed into an infinite well array in infinite formation. Second, based on conformal transformation principle, the infinite well array is transformed into two production and two injection wells in the complex plane. Finally, according to the superposition principle of potential, a new productivity prediction method, which is suitable for the horizontal well in GRCBTBs, was developed. The field measured data of Jingbian gas field of Ordos Basin demonstrate the ability of the method to accurately predict the productivity of the OHHGW in GRCBTBs, and the prediction relative error of absolute open flow of well Longping 1 is only 1.03%, that is to say that the method proposed in this study has a certain guiding significance for the development of horizontal wells in GRCBTBs.

While reliable strategies for constructing block copolymer (BCP) nanowires have been developed, helical nanowires are rarely reported in polymerization-induced self-assembly (PISA). Herein, in this work, a new strategy for constructing helical nanowires was developed via PISA mediated by a fluorinated stabilizer block. Ultralong nanowires with helical structure can be readily produced in a wide range of block compositions. In addition, the generality of this strategy was well testified by expanding monomer types. The achiral BCP nano-objects underwent a morphology transition from spheres to helical nanowires during aging. We believe this work will provide a general strategy for producing helical nanowires through PISA of achiral BCPs.

The network structure in the amorphous domain of swollen iodine-doped poly(vinyl alcohol) (PVA) was systematically investigated by low-field (LF) NMR techniques to reveal the PVA-iodine complex formation mechanism. Three PVA-iodine complexes were obtained under different iodine concentrations (ciodine) of KI/I2 solution: (i) ciodine 1 M: formation of PVA-I3- complex II. It was found that there is no intermediate-magnitude chain motion of PVA under dyeing conditions to induce the substance exchange, as evidenced by the unchanged second moment M2 (∼1.2 × 104 m s-2) at elevated temperature ( 1 M. This suggests more constraints form in the amorphous network for the PVA-I3- complex II system. The constant defects fraction further reveals that the complexation prefers to happen along the tie chains. These results supply a possible formation pathway for the PVA-iodine complexes.

A novel resistive chemical-mechanical sensor for hydrogen gas detection was designed and manufactured by using MEMS processing technology. The sensor combines a composite piezoresistor of silver nanowires-polyimide and a palladium sputtered microcantilever, and the optimized structure of which has been obtained through theoretical and simulation analysis. With a series of experimental testing, the fabricated sensor achieved the ultra-high sensitivity of 2825, 8071, 28250 and 47083 for hydrogen detection at the concentration of 0.4%, 0.8%, 1.2%, 1.6% and 2.0%, respectively. The ultra-high sensitive detection for hydrogen was enabled from the synergistic function of both the surface resistance effect between the palladium coated cantilever and silver nanowires-polyimide piezoresistor, and the bulk resistance effect of the silver nanowires-polyimide piezoresistor. In addition, the sensor also demonstrates excellent stability, which has high potential for practical hydrogen gas detection.

Acid-alkaline balance plays a crucial role in all biological processes. Accordingly, monitoring pH changes will help us to understand the functional status of these physiological and pathological processes. Though fluorescent probes may be a useful tool for detecting pH changes, and there are many limitations to currently available probes, such as background interference, potential cytotoxicity, and poor cell permeability, which call for a solution urgently. In this work, a rhodamine-derived colorimetric and ratiometric sensor (Rh–HN) was fabricated for monitoring pH change via the mechanism of fluorescence resonance energy transfer (FRET). Rh–HN has been shown to possess several advantages over other probes, such as high sensitivity, outstanding permeability, and low toxicity. Besides, the fluorescence intensity ratio (F526/F592) of Rh–HN displays a pH-sensitive response from 2.0 to 7.5 (pKa = 5.05) and linear response from pH 3.8 to 6.4, which was desirable for mapping pH change in the biological systems. Besides, the results indicated that Rh–HN generated a pH-dependent response regulated by switchable forms between closed and opened spirolactam ring. Overall, Rh–HN has accomplished sensing and mapping of pH in living cells, bacteria, and zebrafish. Those results demonstrated that the great potential of Rh–HN in sensing and visualizing pH in the living biosystem.

Molybdenum nitride (δ–MoN) is an important functional material due to its impressive catalytic, energy storage, and superconducting properties. However, the synthesis of δ–MoN usually requires extremely harsh conditions; thus, the insight into δ−MoN is far behind that of oxides and sulfides of molybdenum. Herein, we report that ultrathin δ−MoN nanosheets are prepared at 270 °C and 12 atm. WN, VN, and TiN nanosheets are also synthesized by this method. The δ−MoN nanosheets show strong surface plasmon resonance, high conductivity, excellent thermal and chemical stability as well as a high photothermal conversion efficiency of 61.1%. As a promising surface enhanced Raman scattering substrate, the δ−MoN nanosheets exhibit a 8.16 × 106 enhanced factor and a 10−10 level detection limit for polychlorophenol., Molybdenum nitride is promising for catalysis, energy storage and Raman scattering, but it is synthesized under harsh conditions. Here the authors synthesize highly crystalline molybdenum nitride nanosheets using a relatively mild, non-aqueous solvothermal approach that can be extended to other nitrides.

Triggering receptor expressed on myeloid cells-2 (TREM2) is an innate immune receptor that promotes phagocytosis by microglia. However, whether TREM2 is related to the stimulus-dependent phagocytic activity of microglia is unclear. In this study, the primary cultured microglia were stimulated with interferon (IFN)-γ, interleukin (IL)-4, and interleukin (IL)-10, respectively, and their phagocytic activity against microbeads and apoptotic neural stem cells (NSCs) was measured. TREM2 of microglia was detected by qPCR and western blotting. The TREM2 signal was blocked in microglia using the siRNA technique. The results showed that IL-4 or IL-10 treatment significantly increased the number of microglia gathered around the apoptotic neurosphere. IL-4 and IL-10 treatment also promoted phagocytosis of microbeads and apoptotic NSCs by primary cultured microglia. The TREM2 expression was up-regulated in IL-4- or IL-10- treated microglia. TREM2 siRNA treatment blocked the phagocytic activity of IL-4- or IL-10-treated microglia. In conclusion, these results indicated that IL-4 and IL-10 promote the phagocytic activity of microglia by the up-regulation of TREM2, which suggested a new potential therapeutic target for neurodegenerative disease.

Microglia cells are the main mediators of neuroinflammation. Activation of microglia often aggravates the pathological process of various neurological diseases. Natural chemicals have unique advantages in inhibiting microglia-mediated neuroinflammation and improving neuronal function. Here, we examined the effects of asperosaponin VI (ASA VI) on LPS-activated primary microglia. Microglia were isolated from mice and pretreated with different doses of ASA VI, following lipopolysaccharide (LPS) administration. Activation and inflammatory response of microglia cells were evaluated by real-time fluorescence quantitative polymerase chain reaction (q-PCR), immunohistochemistry and enzyme-linked immunosorbent assay (ELISA). Signaling pathways were detected by western blotting. We found that the ASA VI inhibited the morphological expansion of microglia cells, decreased the expression and release of proinflammatory cytokines, and promoted the expression of antiinflammatory cytokines in a dose-dependent manner. ASA VI also activated PPAR-γ signaling pathway in LPS-treated microglia. The anti-inflammatory effects of ASA VI in microglia were blocked by treating PPAR-γ antagonist (GW9662). These results showed that ASA VI promote the transition of microglia cells from proinflammatory to anti-inflammatory by regulating PPAR-γ pathway.

The alkali-metal molybdate iodate Na3(MoO4)(IO3) (I) and mixed-alkali-metal fluoromolybdate Na3Cs(MoO2F4)2 (II) were obtained via a mild hydrothermal reaction using a "Teflon-pouch" method. I crystallizes in the triclinic space group P1, whose structure comprises a 3D backbone made up of isolated [IO3]- pyramids and [MoO4]2- tetrahedra connected via 5- and 6-fold coordinated sodium cations. II crystallizes in the monoclinic space group P21/c and comprises isolated [MoO2F4]2- octahedra with strong out-of-center distortions and the Na+ as well as Cs+ cations acting as interstitial ions. Both compounds have been characterized by infrared (IR) spectra and ultraviolet-visible-near-infrared (UV-vis-NIR) diffuse reflectance spectra. First-principles calculations respectively reveal that they exhibit birefringence values with Δn = 0.078 and 0.210 at 1064 nm for I and II, and the origin of the birefringence is discussed.

Designing a new adsorbent with recyclability, high efficiency and biodegradability is important for treating heavy metals contamination but remains a severe challenge. In this work, a novel type of hydrogel biosorbents based on pullulan and polydopamine were designed for heavy metal ions removal from aqueous solution. The physicochemical properties of the prepared pullulan/polydopamine (Pu/PDA) hydrogels were fully characterized by thermal gravimetric analysis, Fourier transform infrared spectroscopy, rheology, scanning electron microscopy, swelling and compression tests. We observed that their mechanical strength, pore size, water absorption and retention properties could be nicely controlled by adjusting the PDA concentration in the pre-gel solution. Subsequently, the adsorption ability of designed Pu/PDA hydrogels to Cu2+, Co2+ and Ni2+ was investigated in detail. These hydrogels presented excellent adsorption capability for heavy metal ions and matched well with the pseudo-second-order kinetic model and Freundlich isotherm model. Overall, having tunable physicochemical properties coupled with the high absorption ability for heavy metal ions, these Pu/PDA hydrogels may be a promising strategy for removal of pollutants from aqueous solution.

The selective acylation of indoles often requires sensitive and reactive acyl chloride derivatives. Here, we report a mild, efficient, functional group tolerant, and highly chemoselective N-acylation of indoles using thioesters as a stable acyl source. A series of indoleamides have been obtained with moderate to good yields. In addition, heterocycles, such as carbazole, can also be used as nucleophiles in this reaction.

Background: HF diet-associated fatty liver (is also known as non-alcoholic fatty liver disease, NAFLD) is considered the hepatic component of the metabolic syndrome and has attracted widespread attention due to the increase in its prevalence. Daily dietary management, is considered to be one of the effective strategies for the prevention of NAFLD. In the present study, the effect of quinoa on the hepatic steatosis and the metabolism mechanism were investigated.Methods: Male SD rats simultaneously administered an HF diet and different amounts of quinoa (equivalent to 100 g/day and 300 g/day of human intake, respectively). After 12 weeks of the intervention, Hepatic TG and TC as well as serum anti-oxidative parameters were determined, H&E staining evaluated the hepatic steatosis. Differential metabolite in serum and hepatic tissue were analyzed using UPLC-QTOF-MSE. mRNA expression profile were investigated using RNA-Seq and further verified using real-time RT-PCR.Results: It showed that quinoa effectively controlled the weight of rats, mitigated hepatic steatosis and oxidative stress, which exhibited the beneficial effect of quinoa on prevention of NAFLD. These beneficial effects could be attributed to the regulation of the production of certain metabolites in the circulation system or liver such as LysoPC and PC. The RNA-Seq analysis and RT-PCR verification revealed that an intake of a high amount of quinoa more effectively up-regulated the genes related to lipid metabolism [Apoa (apolipoprotein)5, Apoa4, Apoc2) and down-regulated the genes related immune response [lrf (interferon regulatory factor)5, Tlr6 (Toll like receptor), Tlr10, Tlr11, Tlr12]. Conclusions: Quinoa could alleviate hepatic steatosis due to the regulation of metabolism and the expression of genes related with lipid metabolism and immune response.

The development of low-cost, biocompatible, and durable high-performance substrates is an urgent issue in the field of surface-enhanced Raman scattering (SERS). Herein, by reducing and exfoliating the TiO2-layered nanoplates in the gas phase, nitrogen-doped titanium monoxide (N-TiO) ultrathin nanosheets composed of 2-3 single layers with a thickness of only ∼1.2 nm are synthesized. Compared with pure TiO, the oxidation resistance of N-TiO is greatly improved, in which the oxidation threshold is significantly increased from 187.5 to 415.6 °C. The N-TiO ultrathin nanosheets are found to have strong surface plasmon resonance in the visible region. These ultrathin N-TiO nanosheets can be easily assembled into a large-scale flexible membrane and exhibit remarkable SERS effects. Moreover, this low-cost flexible SERS substrate combines the high durability of noble-metal substrates and the high biocompatibility of semiconductor substrates.

The synthesis of metallic transition metal nitrides (TMNs) has traditionally been performed under harsh conditions, which makes it difficult to prepare TMNs with high surface area and porosity due to the grain sintering. Herein, we report a general and rapid (30 s) microwave synthesis method for preparing TMNs with high specific surface area (122.6-141.7 m2 g-1) and porosity (0.29-0.34 cm3 g-1). Novel single-crystal porous WN, Mo2N, and V2N are first prepared by this method, which exhibits strong surface plasmon resonance, photothermal conversion, and surface-enhanced Raman scattering effects. Different from the conventional low-temperature microwave absorbing media such as water and polymers, as new concept absorbing media, hydrated metal oxides and metallic metal oxides are found to have a remarkable high-temperature microwave heating effect and play key roles in the formation of TMNs. The current research results provide a new-concept microwave method for preparing high lattice energy compounds with high specific surface.

Facing the complex environment of on-site detection, the development of active substrates with wide-spectrum surface-enhanced Raman scattering (SERS) activity is essential. Herein, we report on the low temperature and reproducible synthesis of plasmonic δ-MoN yolk microspheres by in situ-nitriding amorphous MoO2 microspheres at 500 °C and 1 atm. The yolk-structured δ-MoN exhibits strong and wide-spectrum surface plasmon resonance and SERS effects and can perform highly selective detection for probes with different absorption wavelengths under excitation of 532, 633, and 785 nm lasers, with a limitation of 10-11 M and an enhanced factor of 3.6 × 107. Moreover, the plasmonic δ-MoN yolk microspheres have high environmental durability, which can maintain high sensitivity in strong acid and alkaline solutions.

Acute myeloid leukemia (AML) is a malignant tumor of the hematopoietic system, and leukemia stem cells are responsible for AML chemoresistance and relapse. KG-1a cell is considered a leukemia stem cell-enriched cell line, which is resistant to chemotherapy. Arsenic trioxide (ATO) is effective against acute promyelocytic leukemia as a first-line treatment agent, even as remission induction of relapsed cases. ATO has a cytotoxic effect on KG-1a cells, but the mechanism remains unclear. Our results demonstrated that ATO can inhibit cell proliferation, induce apoptosis, and arrest KG-1a cells in the G2/M phase. Using transcriptome analysis, we investigated the candidate target genes regulated by ATO in KG-1a cells. The expression profile analysis showed that the ATO had significantly changed gene expression related to proliferation, apoptosis, and cell cycle. Moreover, MYC, PCNA, and MCM7 were identified as crucial hub genes through protein–protein interaction network analysis; meanwhile, the expressions of them in both RNA and protein levels are down-regulated as confirmed by quantitative polymerase chain reaction and Western blot. Thus, our study suggests that ATO not only inhibits the expression of MYC, PCNA, and MCM7 but also leads to cell cycle arrest and apoptosis in KG-1a cells. Overall, this study provided reliable clues for improving the ATO efficacy in AML.

Ti3C2Tx shows potential as an electrode material of supercapacitors due to its unique layered structures for ion diffusion as well as excellent chemical/physical properties. However, the layer stacking and the insufficient conductivity due to the terminated surface groups have limited this application essentially. In the present study, a three-dimensional B3+ ion-intercalated Ti3C2Tx network (B-Ti3C2Tx) was combined with hollow carbon nanospheres (HCNS), which improved the electric transport performance of Ti3C2Tx by reducing the surface functional groups and hindering the restacking of Ti3C2Tx nanosheets effectively. Thus, a new set of 3D hierarchical B-Ti3C2Tx/HCNS composite materials was obtained here with a superior electrochemical performance higher than that of single Ti3C2Tx in the present study, and many other reported Ti3C2Tx-containing materials in literature. In addition, an excellent electrochemical cycling stability with above 91% retention over 3000 cycles was also obtained for this new hybrid material. This work provides a new direction to promote the Ti3C2Tx-based materials for high-performance supercapacitors.

Functional group transfer reactions are an important synthetic tool in modern organic synthesis. Herein, we developed a new palladium-catalyzed intermolecular transthioetherification reaction of aryl halides with thioethers and thioesters. The synthetic utility and practicality of this catalytic protocol are demonstrated in a wide range of successful transformations (>70 examples). This catalytic protocol is applicable in carbonylative coupling processes as well, and the first example of carbonylative methylthioesterification of aryl halides has been achieved. Notably, this work also provides an approach to using natural products, such as methionine and selenomethionine, as the functional group sources., Functional group transfer reactions are an important synthetic tool in modern organic synthesis.

Herein, polymerization-induced electrostatic self-assembly (PIESA) is conducted to mediate the self-assembly behavior of short interfering RNA (siRNA) for the first time. In PIESA, siRNA not only formed a simple electrostatic polyplex with positively charged polycations, but also facilitated directed self-assembly due to the molecular rigidity of siRNA, leading to appealing nanotubes.

Multifunctional core-shell nanocarriers based on zinc oxide (ZnO)-gated magnetic mesoporous silica nanoparticles (MMSN) were prepared for cancer treatment through magnetic targeting and pH-triggered controlled drug release. Under an external magnetic field, the MMSN could actively deliver chemotherapeutic agent, daunomycin (DNM), to the targeted sites. At neutral aqueous, the functionalized MMSN could stably accommodate the DNM molecules since the mesopores were capped by the ZnO gatekeepers. In contrast, at the acid intercellular environment, the gatekeepers would be removed to control the release of drugs due to the dissolution of ZnO. Meanwhile, ZnO quantum dots not only rapidly dissolve in an acidic condition of cancer cells but also enhance the anti-cancer effect of Zn2+. An in vitro controlled release proliferation indicated that the acid sensitive ZnO gatekeepers showed well response by the ‘on-off’ switch of the pores. Cellular experiments against cervical cancer cell (HeLa cells) further showed that functionalized MMSN significantly suppressed cancer cells growth through synergistic effects between the chemotherapy and Zn2+ ions with monitoring the treatment process. These results suggested that the ZnO-gated MMSN platform is a promising approach to serve as a pH-sensitive system for chemotherapies delivery and Zn2+ controlled release for further application in the treatment of various cancers by synergistic effects.

Inspired by the ring-opening reaction of rhodamine probe induced by metal ions, we proposed a positive charge regulating strategy and designed an “always-on” and “water-soluble” fluorescent probe (o-RPM) based on rhodamine amide bearing o-pyridinium. To our knowledge, o-RPM was the first always-on opening form of spirolactam which can endure broad pH range (pH 3.5–13.0) and aprotic environment. IR and NMR spectrum were used to assess the distribution of conjugation system induced by positive charge in pyridinium moiety. The geometries of o-RPM were calculated using Gaussian software at DFT/B3LYP/6-31 G(d) level. The always-on opening form of o-RPM should be attributed to inductive and conjugation effects resulting from proximal positive charge. Meanwhile, positive charge contributed to the dissolution of o-RPM in aprotic and/or protic solvents. In addition, always-on and water-soluble o-RPM exhibited excellent membrane penetration, and was successfully used as a specific tracker to map the mitochondrial distributions in living MCF-7 cells, due to the nature characteristic of positive charge. It is anticipated that the strategy of ring-opening form of rhodamine spirolactam induced by positive charge might be hopeful to regulate the “on-off-on” state of spirolactams in the biomedical and biological fields.

Two polar molybdenum(VI) iodates(V), NH4[MoO3(IO3)] (1) and KRb[(MoO3)2(IO3)2] (2), have been prepared by a hydrothermal method. They crystallize in noncentrosymmetric (NCS) space groups Pna21 and ...

Compared with noble metals, improving the sensitivity of semiconducting surface-enhanced Raman scattering (SERS) substrates is of great significance to their fundamental research and practical appl...

High quality perovskite films with large columnar grains are greatly desired for efficient perovskite solar cells. Here, low volatility N-methyl-2-pyrrolidone (NMP) was added in MAI/IPA solution in a two-step spin-coating method, which promoted the conversion of lead iodide to perovskite. The perovskite films were annealed by a closed-steam annealing method to prolong the recrystallization process of perovskite films assisted by the residual NMP. It leaded to high quality CH3NH3PbI3 perovskite films with large columnar grains due to its enhancement of the Oswald ripening. The large grain perovskite film leaded to efficient carrier transformation and injection, and low recombination. The photovoltaic performance of the perovskite solar cells was improved significantly.

Lithium metal is among the most promising anode materials for high-energy batteries due to its high theoretical capacity and lowest electrochemical potential. However, uncontrolled lithium decomposition and dendrite formation have hindered its practical applications. Here, we propose a facile and effective strategy using thionyl chloride (SOCl2) as electrolyte additive to in-situ build a stable interfacial protective layer on lithium anode to prevent Li dendrite growth. Furthermore, the decomposition of SOCl2 could produce active sulfur to offer extra capacity for cathode in full battery. As a result, the as-assembled lithium-sulfur battery delivered an ultra-high discharge capacity (2202.3 mA h g−1 at 400 mA g−1) and excellent rate performance (1348.6 mA h g−1 at 3000 mA g−1), as well as remarkable cycling performance. This study reveals an effective avenue to suppress the Li-dendrites growth and provide a significant step towards safe and high-energy Li-S batteries.

To expound the copigmentation effects of phenolics on blackberry wine residue anthocyanins (BWRA), the color and stability of BWRA with storage, thermal, light and oxidation treatments were evaluated by chromaticity, kinetics and structural simulation analysis. Results indicated that phenolic acids showed preferable copigmetation on BWRA solutions with the enhanced color, thermostability at 50–70 °C and light stability, whereas the degradation was accelerated at 90 °C. Meanwhile, flavonoids promoted the oxidation stability of BWRA. Of all the phenolic acids, ferulic acid presented the best copigmentation effect, and among the flavonoids rutin was the most active. Structural simulation suggested rutin and ferulic acid had the largest volume, potential energy (164.8 and 32.8 kcal/mol), minimized energy (39.2 and 11.3 kal/mol) and van der Waals energy (81.6 and 28.1 kcal/mol), respectively, which were favorable to the stabilization of the flavylium ion. The hydrogen bonding, π-π stacking and solvent effects were together involved in the copigmentation mechanism.

Herein, an interesting palladium-catalyzed procedure for the direct carbonylative thiomethylation of aromatic amine derivatives with 4-methylthio-2-butanone is developed. Using 4-methylthio-2-butanone as (methylthio) transfer agent, a variety of corresponding thioesters are obtained with moderate to good yields under base-free condition. In addition, good functional group tolerance can be observed.

Described herein is a comparative theoretical study of dehydrogenative C(sp)-H functionalizations of a terminal alkyne with group-14-based hydrides (HEEt3; E = Si, Ge, Sn) catalyzed by an Ohki-Tatsumi complex-a cationic Ru(II) complex with a tethered thiolate ligand ([Ru-S] = [(DmpS)Ru(PiPr3)][BAr4F]; Dmp = 2,6-(dimesityl)2C6H3; ArF = 3,5-(CF3)2C6H3). The calculations indicate that the energy barriers for heterolytic cleavage of the H-EEt3 bonds at the Ru-S sites of the Ohki-Tatsumi complex highly vary depending on the group 14 elements from 3.8 kcal/mol (E = Sn) to 10.5 kcal/mol (E = Ge) and 18.5 kcal/mol (E = Si), where Ru and S elements cooperatively serve as the Lewis acid and base, respectively. Likewise, the transfer of the group 14 cation (Et3E+) to the C-C triple bond to generate the β-element-stabilized vinyl cations-the rate-determining step (RDS) of the overall reaction-is predicted to be susceptible to the element's identity [Ea = 36.8 for Sn < 42.9 and Ge < 50.7 for Si (kcal/mol)]. The key transition states involved in the RDS are compared in terms of energy and structure within each system of the group 14 hydrides. The distortion/interaction-activation strain (DIAS) model analysis of the transition states responsible for dehydrogenative stannylation and hydrostannation of a terminal alkyne sheds light on the origin of the experimentally observed kinetic preference toward dehydrogenative C-H stannylation over hydrostannation.

Herein, spindle-shaped block copolymer (BCP) nanoparticles are used in seeded polymerization of methyl methacrylate as a novel approach to generating cylindrical nanostructures. The chain-extension of BCP seeds by an amorphous coil-type polymer within the seed core composed of semifluorinated liquid-crystalline blocks triggers the deforming, stretching, and directional growth of the seeds along the long axis, eventually leads to nanorods.

Glycosidases enhance flavor during wine-making by mediating the enzymatic release of aroma molecules. In order to better understand the aroma enhancement potential of Oenococcus oeni SD-2a, β-D-glucosidase (βG) activities in the culture supernatant, whole cells, and disrupted cell lysate were assessed at mid log, late log and stationary growth phase. The enzymatic activity was also compared further from cell cultures with 5 different carbon sources (glucose, cellobiose, arbutin, glucose and cellobiose, glucose and arbutin) at late log phase. Correspondingly, expression levels of 3 bgl genes, OEOE-0224, OEOE-1210, and OEOE-1569 were investigated from cell cultures of the 3 growth phases, and the 5 cell cultures with different carbon sources. Finally, the volatile aroma compounds released by O. oeni SD-2a in synthetic wines with natural glycosides were evaluated by GC-MS. Results showed βG of O. oeni SD-2a was not extracellular enzyme, and the location of it didn't change with the change of growth phase and carbon source studied. βG activities in the whole cells and disrupted cell lysate were similar and constant at the 3 growth phases. As for the carbon sources, βG activities of whole cells and disrupted lysate were positively affected by cellobiose. While arbutin displayed positive and negative effect on βG activity of whole cells and disrupted lysate, respectively. It is probably that bgl genes OEOE-0224 and OEOE-1210 were related to βG activity of SD-2a whole cells, while OEOE-1569 was responsible for βG activity of disrupted lysate. More kinds of volatile compounds and higher total concentration were released by SD-2a in synthetic wine compared with control. Thus, SD-2a showed a great potential for flavor enhancement under wine-like conditions. This study provides more information for further study of βG activity from O. oeni SD-2a.

Alcohol drinking has been established as a major risk factor for esophageal diseases. Our previous study showed that ethanol exposure inhibited PAX9 expression in human esophageal squamous epithelial cells in vitro and in vivo. In this study, we aimed to investigate the molecular pathways through which alcohol drinking suppresses PAX9 in esophageal squamous epithelial cells. We first demonstrated the inhibition of NOTCH by ethanol exposure in vitro. NOTCH regulated PAX9 expression in KYSE510 and KYSE410 cells in vitro and in vivo. RBPJ and NOTCH intracellular domain (NIC) D1 ChIP-PCR confirmed Pax9 as a direct downstream target of NOTCH signaling in mouse esophagus. NOTCH inhibition by alcohol drinking was further validated in mouse esophagus and human tissue samples. In conclusion, ethanol exposure inhibited NOTCH signaling and thus suppressed PAX9 expression in esophageal squamous epithelial cells in vitro and in vivo. Our data support a novel mechanism of alcohol-induced esophageal injury through the inhibition of NOTCH-PAX9 signaling. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

In this work, a reaction-based ratiometric and colorimetric sensor was designed and synthesized for probing bisulfite (HSO3-) by coupling coumarin (CM) with barbituric (BA) moiety. Further tests have shown that CM-BA has high selectivity and sensitivity for the recognition of HSO3-, which can be applied for the detection of HSO3- in environmental and biological systems very effectively. The fluorescence intensity ratios (F462/F568) exhibited an outstanding HSO3--dependent response with ultrafast response time (within 20 s) and a lower detection limit (105 nM). Meanwhile, the color of the CM-BA solution changed from green to colorless during the recognition process, and its fluorescence changed from green to blue. The mechanism of response is confirmed by the density functional theory (DFT) model. In summary, CM-BA has demonstrated low toxicity and good permeability, which can be applied for imaging HSO3- in cells and zebrafish safely and effectively. Besides, this novel sensor CM-BA successfully realized the quantification of the concentration of HSO3- in paper strips and food samples.

Background. Esophageal carcinoma (ESCA) is not only a threat to people’s health but also the sixth most common cause of cancer-related mortality worldwide. Methods. In this study, the key targets of ESCA are screened through GeneCards and DisGeNET databases combined with the Gene Expression Omnibus (GEO) database (GSE1420 and GSE20347). Then, data associated with ESCA samples are downloaded from The Cancer Genome Atlas (TCGA) database for integrated analysis. Moreover, the effect of epithelial cell adhesion molecule (EpCAM) expression on the survival of patients with ESCA is evaluated by Kaplan–Meier and Cox analyses. The virtual screening is carried out using a Suflex-Dock molecular docking module. The chemical components, which have been well bound to EpCAM, are screened out based on a total score >5 as a threshold. Ginsenosides and EpCAM are analyzed by LigPlot + v.2.2 software to identify the binding sites. Results. Four ESCA targets are obtained from GeneCards, DisGeNET, and GEO databases. In this study, it is found that high EpCAM expression is associated with histologic grade, stage, patient age, N classification, T classification, and radiation therapy. The Kaplan–Meier curves for overall survival also show that the higher expression of EpCAM is associated with worse outcomes in patients with ESCA. Univariate and multivariate Cox analyses indicate that EpCAM mRNA expression might be a useful biomarker for ESCAP<0.05. Molecular docking technology suggests that ginsenoside Rg3 and ginsenoside Rh2 can easily establish good docking modes and have a high affinity with EpCAM. The 6′-hydroxyl and 6″-hydroxyl on the 3-glycosyl of ginsenoside Rg3 are prone to form hydrogen bonds (Lys151 and Lys221) with the active sites of EpCAM ligand binding domain. The hydroxyl groups on the 12 sites of the ginsenoside Rh2 glycoside framework are found to have hydrogen bonding with Leu240. The formation of hydrogen bonds plays an important role in binding of ginsenoside Rg3 and ginsenoside Rh2 to EpCAM, as well as the stability of EpCAM conformation. Conclusion. EpCAM may be determined as a potential biomarker for early diagnosis and prognosis of ESCA. Ginsenoside Rg3 and ginsenoside Rh2 have potential antiesophageal cancer activities. This experiment provides a reference for the study of the chemical compositions of ginsenosides in the treatment of esophageal cancer.

The diverse oxyfluoride species and vast number of different topological arrangements lead to fluorooxoborates’ structural beauty and richness. Herein, the first mixed alkali/alkaline-earth metal fluorooxoborate Ba3B10O17F2·0.1KF was successfully synthesized and systemically characterized. Its most important structural feature is an unprecedented double-layered B–O/F anionic arrangement.

In this article, we report a chloro-rhodamine (ClR) dye as a potential novel probe scaffold that possesses a specific intra-subspiral cyclization behavior: the acetylation of ClR (ClR-Ac) features a closed-loop structure in an aqueous solution, while the ClR itself is an open-loop structure. ClR-Ac is colorless and completely nonfluorescent, while ClR is yellowish and strongly fluorescent. This discovery has led to the development of a general design strategy to develop highly sensitive fluorescence probes for peptidase. We designed and synthesized the probe ClR-Glu by peptidase represented by γ-glutamyl-transpeptidase (GGT) to verify this strategy. Experimental results show that ClR is easier to synthesize and has better environmental pH stability than the GGT probe based on HMRG. Furthermore, in addition, we expect that ClR-based probes will be widely used for the detection of peptidases and other analyses.