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[Display omitted] • A general but efficient "three-in-one" synthetic strategy for PCMs was developed. • Pyrolysis of EDTA-4Na in air led to AC with more oxygenated groups and mesopores. • As-formed AC was a universal carrier for selected Pt group metal (Ru, Rh, Ir) NPs. • The optimal Ru/AC had the highest HER activity with a low overpotential of 7 mV. • The small Ru NPs with electron-rich sites contributed to the high performance. Heteroatom-doped porous carbons are widely exploited as efficient matrices to stabilize metal nanoparticles (NPs) for electrocatalysis, whereas their syntheses without additional activation and functional agents and inert gases still remains a grand challenge. Herein, we report the simple yet efficient inert gas-free direct fabrication of hierarchically porous interconnected O/N-codoped carbon nanosheets (designated as AC) and their application as excellent matrices for preparing selected Pt group metal (Ru, Rh, Ir) electrocatalysts toward alkaline hydrogen evolution reaction (HER). The self-templating, self-activation and in-situ O/N-functionalization synthesis of AC is achieved via the one-pot pyrolysis of ethylenediaminetetraacetic acid tetra-sodium without additional inert gas. Compared with NC prepared via annealing the same precursor in N 2 atmosphere, the as-formed AC with more mesoporous structure and oxygenated functional groups enables the fabrication of smaller and electron-rich Ru NPs, which deliver an optimal HER activity in terms of an extremely low overpotential of 7 mV at 10 mA cm−2 for HER, superior to that of Rh/AC, Ir/AC, Ru/NC, commercial Pt/C and plenty of previously fabricated Ru-based electrocatalysts. This "three-in-one" synthetic method demonstrates superior generality for other porous carbon materials by using potassium gluconate and potassium sodium tartrate as precursors. [ABSTRACT FROM AUTHOR]

[Display omitted] • A general but efficient "three-in-one" synthetic strategy for PCMs was developed. • Pyrolysis of EDTA-4Na in air led to AC with more oxygenated groups and mesopores. • As-formed AC was a universal carrier for selected Pt group metal (Ru, Rh, Ir) NPs. • The optimal Ru/AC had the highest HER activity with a low overpotential of 7 mV. • The small Ru NPs with electron-rich sites contributed to the high performance. Heteroatom-doped porous carbons are widely exploited as efficient matrices to stabilize metal nanoparticles (NPs) for electrocatalysis, whereas their syntheses without additional activation and functional agents and inert gases still remains a grand challenge. Herein, we report the simple yet efficient inert gas-free direct fabrication of hierarchically porous interconnected O/N-codoped carbon nanosheets (designated as AC) and their application as excellent matrices for preparing selected Pt group metal (Ru, Rh, Ir) electrocatalysts toward alkaline hydrogen evolution reaction (HER). The self-templating, self-activation and in-situ O/N-functionalization synthesis of AC is achieved via the one-pot pyrolysis of ethylenediaminetetraacetic acid tetra-sodium without additional inert gas. Compared with NC prepared via annealing the same precursor in N 2 atmosphere, the as-formed AC with more mesoporous structure and oxygenated functional groups enables the fabrication of smaller and electron-rich Ru NPs, which deliver an optimal HER activity in terms of an extremely low overpotential of 7 mV at 10 mA cm−2 for HER, superior to that of Rh/AC, Ir/AC, Ru/NC, commercial Pt/C and plenty of previously fabricated Ru-based electrocatalysts. This "three-in-one" synthetic method demonstrates superior generality for other porous carbon materials by using potassium gluconate and potassium sodium tartrate as precursors. [ABSTRACT FROM AUTHOR]

Abstract: The preparation of a new surface-active sulfonated phosphine and its catalytic performance in aqueous biphasic hydroformylation of long chain olefins were reported. The amphiphilic phosphine: sodium salt of sulfonated n-C12H25O C6H4P(C6H4-p-CH3O)2 (DMOPPS) was prepared by sulfonation of the hydrophobic phosphine DMOPP in concentrated H2SO4 under N2 atmosphere at 30°C for about 5h. The rhodium complex, RhCl(CO)(TPPTS)2 [TPPTS=P(C6H4-m-SO3Na)3], was used as the catalyst precursor. The catalytic active species with the DMOPPS as ligand was in situ formed by adding DMOPPS to the RhCl(CO)(TPPTS)2 catalyst precursor. The surface-activity and micelle-forming property of this new amphiphilic phosphine were confirmed by using cryogenic transmission electron microscope (Cryo-TEM). Under the same conditions, the biphasic hydroformylation of 1-decene using DMOPPS as ligand was compared with that using traditional TPPTS as ligand. The catalysis system using DMOPPS was also compared with the previous Rh-TPPTS-surfactant [C12H25N(CH3)3I (DTAI)] system. Some reaction parameters such as stirring rates, alkyl chain length of olefins, the molar ratio of phosphine/rhodium, and the catalyst recycle were also studied in detail. The results showed that the ligand DMOPPS exhibited a micelle-forming property that could significantly enhance the hydroformylation reaction rate of long chain olefin. Moreover, the surface-active phosphine may also stabilize the aqueous/oil phase boundary, which could enhance the biphasic catalytic reaction rates. [Copyright &y& Elsevier]

Abstract: We report here the humanization of two mouse monoclonal antibodies (mAb) using framework shuffling of human germline genes. mAbs EA2 and 47 were raised against the human receptor tyrosine kinase EphA2 and EphB4, respectively, which exhibit increased expression levels in many cancer cell lines. One- and two-step strategies were carried out, in which the light and heavy chains of each parental mAb were simultaneously or sequentially humanized. We characterized in detail these newly humanized antibodies in terms of binding affinity to their respective antigen, functional activity, thermostability, electric charge and expression yields. Three previously described framework shuffled, humanized versions of another mouse anti-human EphA2 antibody (mAb B233) were similarly characterized. We show that several of these parameters were either maintained or improved in all humanized molecules when compared with their respective chimaeric counterpart. Therefore, this humanization approach is generally applicable to non-human IgGs and allows for the specific selection of antibodies and antibody fragments exhibiting favorable functional, biochemical and biophysical properties. [Copyright &y& Elsevier]

We have shown that cytotoxic T lymphocytes specific for PR1, an HLA-A2-restricted nonopeptide derived from proteinase 3, kill leukemia cells and may contribute to the elimination of chronic myelogenous leukemia (CML) after treatment with IFN or allogeneic bone marrow transplant. Some patients with persistent disease also have circulating PR1-specific T cells, however, suggesting the likelihood of immune tolerance. Here we show that both high- and low-avidity PR1-specific T cells from the peripheral blood of healthy donors can be identified and selectively expanded in vitro. Although high-avidity PR1-specific T cells killed CML more effectively than low-avidity T cells, only high-avidity T cells underwent apoptosis when stimulated with high PR1 peptide concentration or when exposed to leukemia that overexpressed proteinase 3. No high-avidity PR1-specific T cells could be identified or expanded from newly diagnosed leukemia patients, whereas low-avidity T cells were readily expanded. Circulating high-avidity PR1-specific T cells were identified in IFN-sensitive patients in cytogenetic remission, however. These results provide evidence that CML shapes the host immune response and that leukemia outgrowth may result in part from leukemia-induced selective deletion of high-avidity PR1-specific T cells. [ABSTRACT FROM AUTHOR]

Researchers have been committed to reducing the hazardous pollutants by developing efficient catalysts while ignoring the pollution caused by the use of toxic surface capping agents, reductants and/or organic solvents in the catalyst preparation process. To alleviate such problems, we here report a novel one-step oxygenated functional group-driven electroless deposition strategy to synthesize clean and uniformly distributed Pd nanoparticles (NPs) using porous carbon nanosheets (PCN) as both substrates and reducing agents. It is observed that the oxygenated functional groups enriched PCN possesses a low work function and allows the spontaneous reduction of PdCl 4 2− ions to Pd NPs deposited on the PCN support (Pd/PCN). The particle size of Pd NPs can be flexibly modulated by simply controlling the immersing time and thereby their maximum catalytic performances can be achieved. Specifically, the optimal Pd/PCN-08 with a Pd loading of 3.0 wt% shows an excellent activity with a turnover frequency of 0.38 min−1 for electrocatalytic hydrodechlorination (ECH) of 4-chlorophenol (4-CP), superior to the previously reported materials. The stability of Pd/PCN-08 for 4-CP ECH is impressive in repetitive cycles. This work proposes a facile and efficient strategy to synthesize high-performance catalysts for detoxifying the hazardous organic pollutants. ga1 • The abundant oxygenated functional groups enable PCN with strong reducibility. • The spontaneous redox between PdCl 4 2− and PCN leads to the formation of Pd/PCN. • Pd/PCN-08 exhibited a high reaction constant of 3.9 × 10−2 min−1 toward 4-CP ECH. • The stability of Pd/PCN-08 for 4-CP ECH was impressive in repetitive cycles. [ABSTRACT FROM AUTHOR]

A new fluorophore 7-(diphenylamino)coumarin-4-yl pivalate (DPACP) with solvatochromism, aggregation-induced emission (AIE) and mechanofluorochromic (MFC) enhancement characteristics was rationally designed and synthesized by attaching bulky diphenylamine electron-donor and pivalate ester electron-acceptor to coumarin. With solvent polarity increase from n-hexane to acetonitrile, this molecular displayed a bathochromic shift in the emission wavelength (from 436 nm to 553 nm) and a decrease in the quantum yield (from 81.1% to 2.8%), indicating solvatochromic effect. Also, the AIE behaviors were observed in CH 3 CN/water and THF/water mixture systems. For example, the PL intensity increased 6 times in mixed solvent (CH 3 CN: water = 10 : 90) compared to that in pure CH 3 CN. Moreover, the emission of original powder samples was red-shifted (from 438 nm to 483 nm) with fluorescence enhancement (the solid-state quantum yield increase from 19% to 28%) upon grinding, and the emission behaviors of grinding powder samples could be reverted to original state by wetting with n-hexane. Furthermore, the relationship among the molecular structure, intermolecular interactions and emission properties was investigated by single-crystal diffraction analysis. DPACP had a twisted conformation because of steric hindrance from diphenylamine and pivalate ester groups, which played a decisive role in realizing AIE and MFC enhancement behaviors. The absence of π-π stacking observed in single-crystal structure was the main reason for the AIE property. The MFC enhancement property could be ascribed to the disturbance of weak electrostatic interaction of adjacent molecules upon grinding. The bulky group of pivalate ester was first used to construct MFC molecule, and this work provided insights for developing AIE and MFC materials based on conventional planar fluorophore which was always subject to ACQ effect. Image 1 • A new coumarin fluorophore with AIE and MFC enhancement properties was developed. • It was shown that twisted molecule conformation was crucial for AIE and MFC behaviors. • The bulky group of pivalate ester was first used to construct AIE and MFC molecule. • The fluorescence quantum yields of the compound in n-hexane reached to 0.81. [ABSTRACT FROM AUTHOR]

Recent studies have shown that the treatment of nonmetastatic K-1735 murine melanoma cells with cytokines induces the production of nitric oxide (NO) and hence cell death. The purpose of this study was to determine the mechanism of this cytokine-induced NO-mediated apoptosis. Incubation of nonmetastatic K-1735 cells with interleukin-1 alpha (IL-1α) and interferon-gamma (IFN-γ) induced high NO production, Bcl-2 downregulation, and apoptotic cell death. In contrast, incubation of metastatic K-1735 cells with IL-1α and IFN-γ did not induce significant production of NO, downregulation of Bcl-2, or cell death. The exposure to exogenous NO derived from the NO donors, sodium nitroprusside (SNP), or GEA5024 produced a dose-dependent apoptotic cell death in both the metastatic and nonmetastatic K-1735 cells, which was associated with downregulation of Bcl-2 at the mRNA level and, to a lesser extent, at the protein level. Nonmetastatic and metastatic K-1735 cells transfected with the Bcl-2 gene were more resistant to apoptosis mediated by both endogenous and exogenous NO. Subsequent to intravenous injection, the tumor cells transfected with the Bcl-2 gene had an increased survival rate in the lungs of nude mice and produced a higher number of experimental lung metastases. These data suggest that NO-induced apoptosis in K-1735 melanoma cells is associated with downregulation of Bcl-2. [ABSTRACT FROM AUTHOR]

Carbazole (CA) and alkylated carbazoles are common nitrogen-containing heterocyclic aromatic compounds widely found in crude oils and sedimentary rocks extracts. Their geochemical significances in petroleum exploration have been widely investigated in previous studies. Using density functional theory (DFT) and molecular dynamics (MD) simulation, we calculated the polarity of alkylated carbazole isomers/homologues and their adsorption energy with water and α-quartz, respectively. The calculated results show that there are significant differences in migration fractionation effects for alkylated carbazole isomers/homologues. This study confirmed the validity of previously proposed carbazole migration indicators, i.e. 4-/1-MCA (the relative abundance of 4-methylcarbazole to 1-methylcarbazole), 2,5-/1,8-DMCA (2,5-dimethylcarbazole to 1,8-dimethylcarbazole) and 2,4-/1,8-DMCA (2,4-dimethylcarbazole to 1,8-dimethylcarbazole) on the basis of quantum chemistry and molecular simulation. All these three parameters have been successfully applied in a lacustrine sandstone reservoir in the Fushan Depression, Beibuwan Basin (South China Sea). The calculations of Gibbs free energy show that the differences in thermal stability between the isomers of alkylcarbazoles can be negligible. The source input and depositional environment have no significant effect on these indicators for oils from a same oil family. Hence, the values of these parameters are mainly controlled by subsurface petroleum migration processes. Therefore, the molecular parameters relative to alkylated carbazoles can be used as practically effective geochemical markers to trace the oil filling orientation and pathways for subsurface oil migration. • Geochromatography of alkylcarbazoles was calculated by molecular dynamics simulation. • Three indicators were proposed to trace oil migration orientation. • Alkylcarbazoles were successfully applied in lacustrine sandstone reservoirs. • The effect of maturity and depositional environment were discussed. [ABSTRACT FROM AUTHOR]

• A new mechanochromic luminescence (MCL) compound based on coumarin oxime was developed. • The formation of H-aggregate was considered to be responsible for MCL property. • Intermolecular H-bonding caused by -C=N-OH played a key role in H-aggregate formation. For the organic luminogens, the packing structure and fluorescent emission of H-aggregate could be affected by mechanical stimuli. According to the finding, here a new coumarin oxime derivative 4-chloro-7-(diethylamino)-coumarin-3-carbaldehyde oxime A1 showing reversible mechanochromic luminescence (MCL) property was developed. Optical properties study in the solution and DFT calculation revealed that A1 had ICT nature. The emission wavelength in solid state of A1 changed reversibly from 515 nm to 540 nm upon mechanical stimuli and solvent treatment. To demonstrate the relationship between MCL property and molecular structure, another three relative coumarin oxime compounds were synthesized. The results showed that the formation of H-aggregate in solid state observed by X-ray diffraction analysis was considered to be responsible for MCL property of A1 , and the intermolecular H-bonding caused by oxime hydroxyl group played a key role in the formation of H-aggregate. Furthermore, the potential application in rewritable data storage based on the MCL behavior of A1 was studied. [ABSTRACT FROM AUTHOR]

In this study, a newly created Fortran program was used to assist in the constructing of a sub-bituminous coal model (SCM). Followed by grand canonical Monte Carlo simulations, the adsorption behaviors of CBM adsorption on dry-/moisture-SCM systems have been systematically studied at different pressure-temperature conditions. A geological model with typical geothermal and pressure gradients was established to investigate the effect of coupled pressure and temperature on the absorption and recovery. As a result, pure-N 2 injection has been confirmed to paly a negative role on CH 4 recovery, whereas CO 2 could effectively improve the CO 2 sequestration and CH 4 displacement. Meanwhile, the adsorption percentage (δ) and the recovery efficiency (η) were first put forward in terms of theoretical calculations. The results showed that, the δ was determined by pore size distribution of the SCM, adsorption temperature/pressure, moisture-containing in coal and the types of adsorbates. The value of η C H 4 is 53.07% in dry coal seam, whereas 47.20% is evaluated in moisture coal seam, the corresponding optimum mining depths are 600 m and 800 m, respectively. Remarkably, water-containing in coal seam has an obviously inhibitory effect on simultaneous extraction of coal and gas, and it should be valued in the follow-up studies. Based on this principle, the optimum mining depth for CO 2 -ECBM was predicted to be ∼800 m in actual deep coal seams through our geological model. Our results provide a molecular-scale insight into CBM recovery efficiency in coal at different burial depths, and offer useful guidance for realistic exploitation. [ABSTRACT FROM AUTHOR]

Traditional constant false alarm rate (CFAR) methods have shown their potential for foreign object debris (FOD) indication. However, the performance of these methods would deteriorate under the complex clutter background in airport scenes. This paper presents a threshold-improved approach based on the cell-averaging clutter-map (CA-CM-) CFAR and tests it on a millimeter-wave (MMW) radar system. Clutter cases are first classified with variability indexes (VIs). In homogeneous background, the threshold is calculated by the student-t-distributed test statistic; under the discontinuous clutter conditions, the threshold is modified according to current VI conditions, in order to address the performance decrease caused by extended clutter edges. Experimental results verify that the chosen targets can be indicated by the t-distributed threshold in homogeneous background. Moreover, effective detection of the obscured targets could also be achieved with significant detectability improvement at extended clutter edges. [ABSTRACT FROM AUTHOR]

Security risks and economic losses of civil aviation caused by Foreign Object Debris (FOD) have increased rapidly. Synthetic Aperture Radars (SARs) with high resolutions potentially have the capability to detect FODs on the runways, but the target echo is hard to be distinguished from strong clutter. This paper proposes a clutter-analysis-based Space-time Adaptive Processing (STAP) method in order to obtain effective clutter suppression and moving FOD indication, under inhomogeneous clutter background. Specifically, we first divide the radar coverage into equal scattering cells in the rectangular coordinates system rather than the polar ones. We then measure normalized RCSs within the X-band and employ the acquired results to modify the parameters of traditional models. Finally, we describe the clutter expressions as responses of the scattering cells in space and time domain to obtain the theoretical clutter covariance. Experimental results at 10 GHz show that FODs with a reflection higher than −30 dBsm can be effectively detected by a Linear Constraint Minimum Variance (LCMV) filter in azimuth when the noise is −60 dBm. It is also validated to indicate a −40 dBsm target in Doppler. Our approach can obtain effective clutter suppression 60dB deeper than the training-sample-coupled STAP under the same conditions. [ABSTRACT FROM AUTHOR]